| File: | llvm/lib/Transforms/Vectorize/LoopVectorize.cpp |
| Warning: | line 2365, column 9 Value stored to 'InitVecValSTy' during its initialization is never read |
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| 1 | //===- LoopVectorize.cpp - A Loop Vectorizer ------------------------------===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | // |
| 9 | // This is the LLVM loop vectorizer. This pass modifies 'vectorizable' loops |
| 10 | // and generates target-independent LLVM-IR. |
| 11 | // The vectorizer uses the TargetTransformInfo analysis to estimate the costs |
| 12 | // of instructions in order to estimate the profitability of vectorization. |
| 13 | // |
| 14 | // The loop vectorizer combines consecutive loop iterations into a single |
| 15 | // 'wide' iteration. After this transformation the index is incremented |
| 16 | // by the SIMD vector width, and not by one. |
| 17 | // |
| 18 | // This pass has three parts: |
| 19 | // 1. The main loop pass that drives the different parts. |
| 20 | // 2. LoopVectorizationLegality - A unit that checks for the legality |
| 21 | // of the vectorization. |
| 22 | // 3. InnerLoopVectorizer - A unit that performs the actual |
| 23 | // widening of instructions. |
| 24 | // 4. LoopVectorizationCostModel - A unit that checks for the profitability |
| 25 | // of vectorization. It decides on the optimal vector width, which |
| 26 | // can be one, if vectorization is not profitable. |
| 27 | // |
| 28 | // There is a development effort going on to migrate loop vectorizer to the |
| 29 | // VPlan infrastructure and to introduce outer loop vectorization support (see |
| 30 | // docs/Proposal/VectorizationPlan.rst and |
| 31 | // http://lists.llvm.org/pipermail/llvm-dev/2017-December/119523.html). For this |
| 32 | // purpose, we temporarily introduced the VPlan-native vectorization path: an |
| 33 | // alternative vectorization path that is natively implemented on top of the |
| 34 | // VPlan infrastructure. See EnableVPlanNativePath for enabling. |
| 35 | // |
| 36 | //===----------------------------------------------------------------------===// |
| 37 | // |
| 38 | // The reduction-variable vectorization is based on the paper: |
| 39 | // D. Nuzman and R. Henderson. Multi-platform Auto-vectorization. |
| 40 | // |
| 41 | // Variable uniformity checks are inspired by: |
| 42 | // Karrenberg, R. and Hack, S. Whole Function Vectorization. |
| 43 | // |
| 44 | // The interleaved access vectorization is based on the paper: |
| 45 | // Dorit Nuzman, Ira Rosen and Ayal Zaks. Auto-Vectorization of Interleaved |
| 46 | // Data for SIMD |
| 47 | // |
| 48 | // Other ideas/concepts are from: |
| 49 | // A. Zaks and D. Nuzman. Autovectorization in GCC-two years later. |
| 50 | // |
| 51 | // S. Maleki, Y. Gao, M. Garzaran, T. Wong and D. Padua. An Evaluation of |
| 52 | // Vectorizing Compilers. |
| 53 | // |
| 54 | //===----------------------------------------------------------------------===// |
| 55 | |
| 56 | #include "llvm/Transforms/Vectorize/LoopVectorize.h" |
| 57 | #include "LoopVectorizationPlanner.h" |
| 58 | #include "VPRecipeBuilder.h" |
| 59 | #include "VPlan.h" |
| 60 | #include "VPlanHCFGBuilder.h" |
| 61 | #include "VPlanPredicator.h" |
| 62 | #include "VPlanTransforms.h" |
| 63 | #include "llvm/ADT/APInt.h" |
| 64 | #include "llvm/ADT/ArrayRef.h" |
| 65 | #include "llvm/ADT/DenseMap.h" |
| 66 | #include "llvm/ADT/DenseMapInfo.h" |
| 67 | #include "llvm/ADT/Hashing.h" |
| 68 | #include "llvm/ADT/MapVector.h" |
| 69 | #include "llvm/ADT/None.h" |
| 70 | #include "llvm/ADT/Optional.h" |
| 71 | #include "llvm/ADT/STLExtras.h" |
| 72 | #include "llvm/ADT/SmallPtrSet.h" |
| 73 | #include "llvm/ADT/SmallSet.h" |
| 74 | #include "llvm/ADT/SmallVector.h" |
| 75 | #include "llvm/ADT/Statistic.h" |
| 76 | #include "llvm/ADT/StringRef.h" |
| 77 | #include "llvm/ADT/Twine.h" |
| 78 | #include "llvm/ADT/iterator_range.h" |
| 79 | #include "llvm/Analysis/AssumptionCache.h" |
| 80 | #include "llvm/Analysis/BasicAliasAnalysis.h" |
| 81 | #include "llvm/Analysis/BlockFrequencyInfo.h" |
| 82 | #include "llvm/Analysis/CFG.h" |
| 83 | #include "llvm/Analysis/CodeMetrics.h" |
| 84 | #include "llvm/Analysis/DemandedBits.h" |
| 85 | #include "llvm/Analysis/GlobalsModRef.h" |
| 86 | #include "llvm/Analysis/LoopAccessAnalysis.h" |
| 87 | #include "llvm/Analysis/LoopAnalysisManager.h" |
| 88 | #include "llvm/Analysis/LoopInfo.h" |
| 89 | #include "llvm/Analysis/LoopIterator.h" |
| 90 | #include "llvm/Analysis/OptimizationRemarkEmitter.h" |
| 91 | #include "llvm/Analysis/ProfileSummaryInfo.h" |
| 92 | #include "llvm/Analysis/ScalarEvolution.h" |
| 93 | #include "llvm/Analysis/ScalarEvolutionExpressions.h" |
| 94 | #include "llvm/Analysis/TargetLibraryInfo.h" |
| 95 | #include "llvm/Analysis/TargetTransformInfo.h" |
| 96 | #include "llvm/Analysis/VectorUtils.h" |
| 97 | #include "llvm/IR/Attributes.h" |
| 98 | #include "llvm/IR/BasicBlock.h" |
| 99 | #include "llvm/IR/CFG.h" |
| 100 | #include "llvm/IR/Constant.h" |
| 101 | #include "llvm/IR/Constants.h" |
| 102 | #include "llvm/IR/DataLayout.h" |
| 103 | #include "llvm/IR/DebugInfoMetadata.h" |
| 104 | #include "llvm/IR/DebugLoc.h" |
| 105 | #include "llvm/IR/DerivedTypes.h" |
| 106 | #include "llvm/IR/DiagnosticInfo.h" |
| 107 | #include "llvm/IR/Dominators.h" |
| 108 | #include "llvm/IR/Function.h" |
| 109 | #include "llvm/IR/IRBuilder.h" |
| 110 | #include "llvm/IR/InstrTypes.h" |
| 111 | #include "llvm/IR/Instruction.h" |
| 112 | #include "llvm/IR/Instructions.h" |
| 113 | #include "llvm/IR/IntrinsicInst.h" |
| 114 | #include "llvm/IR/Intrinsics.h" |
| 115 | #include "llvm/IR/LLVMContext.h" |
| 116 | #include "llvm/IR/Metadata.h" |
| 117 | #include "llvm/IR/Module.h" |
| 118 | #include "llvm/IR/Operator.h" |
| 119 | #include "llvm/IR/PatternMatch.h" |
| 120 | #include "llvm/IR/Type.h" |
| 121 | #include "llvm/IR/Use.h" |
| 122 | #include "llvm/IR/User.h" |
| 123 | #include "llvm/IR/Value.h" |
| 124 | #include "llvm/IR/ValueHandle.h" |
| 125 | #include "llvm/IR/Verifier.h" |
| 126 | #include "llvm/InitializePasses.h" |
| 127 | #include "llvm/Pass.h" |
| 128 | #include "llvm/Support/Casting.h" |
| 129 | #include "llvm/Support/CommandLine.h" |
| 130 | #include "llvm/Support/Compiler.h" |
| 131 | #include "llvm/Support/Debug.h" |
| 132 | #include "llvm/Support/ErrorHandling.h" |
| 133 | #include "llvm/Support/InstructionCost.h" |
| 134 | #include "llvm/Support/MathExtras.h" |
| 135 | #include "llvm/Support/raw_ostream.h" |
| 136 | #include "llvm/Transforms/Utils/BasicBlockUtils.h" |
| 137 | #include "llvm/Transforms/Utils/InjectTLIMappings.h" |
| 138 | #include "llvm/Transforms/Utils/LoopSimplify.h" |
| 139 | #include "llvm/Transforms/Utils/LoopUtils.h" |
| 140 | #include "llvm/Transforms/Utils/LoopVersioning.h" |
| 141 | #include "llvm/Transforms/Utils/ScalarEvolutionExpander.h" |
| 142 | #include "llvm/Transforms/Utils/SizeOpts.h" |
| 143 | #include "llvm/Transforms/Vectorize/LoopVectorizationLegality.h" |
| 144 | #include <algorithm> |
| 145 | #include <cassert> |
| 146 | #include <cstdint> |
| 147 | #include <cstdlib> |
| 148 | #include <functional> |
| 149 | #include <iterator> |
| 150 | #include <limits> |
| 151 | #include <memory> |
| 152 | #include <string> |
| 153 | #include <tuple> |
| 154 | #include <utility> |
| 155 | |
| 156 | using namespace llvm; |
| 157 | |
| 158 | #define LV_NAME"loop-vectorize" "loop-vectorize" |
| 159 | #define DEBUG_TYPE"loop-vectorize" LV_NAME"loop-vectorize" |
| 160 | |
| 161 | #ifndef NDEBUG |
| 162 | const char VerboseDebug[] = DEBUG_TYPE"loop-vectorize" "-verbose"; |
| 163 | #endif |
| 164 | |
| 165 | /// @{ |
| 166 | /// Metadata attribute names |
| 167 | const char LLVMLoopVectorizeFollowupAll[] = "llvm.loop.vectorize.followup_all"; |
| 168 | const char LLVMLoopVectorizeFollowupVectorized[] = |
| 169 | "llvm.loop.vectorize.followup_vectorized"; |
| 170 | const char LLVMLoopVectorizeFollowupEpilogue[] = |
| 171 | "llvm.loop.vectorize.followup_epilogue"; |
| 172 | /// @} |
| 173 | |
| 174 | STATISTIC(LoopsVectorized, "Number of loops vectorized")static llvm::Statistic LoopsVectorized = {"loop-vectorize", "LoopsVectorized" , "Number of loops vectorized"}; |
| 175 | STATISTIC(LoopsAnalyzed, "Number of loops analyzed for vectorization")static llvm::Statistic LoopsAnalyzed = {"loop-vectorize", "LoopsAnalyzed" , "Number of loops analyzed for vectorization"}; |
| 176 | STATISTIC(LoopsEpilogueVectorized, "Number of epilogues vectorized")static llvm::Statistic LoopsEpilogueVectorized = {"loop-vectorize" , "LoopsEpilogueVectorized", "Number of epilogues vectorized" }; |
| 177 | |
| 178 | static cl::opt<bool> EnableEpilogueVectorization( |
| 179 | "enable-epilogue-vectorization", cl::init(true), cl::Hidden, |
| 180 | cl::desc("Enable vectorization of epilogue loops.")); |
| 181 | |
| 182 | static cl::opt<unsigned> EpilogueVectorizationForceVF( |
| 183 | "epilogue-vectorization-force-VF", cl::init(1), cl::Hidden, |
| 184 | cl::desc("When epilogue vectorization is enabled, and a value greater than " |
| 185 | "1 is specified, forces the given VF for all applicable epilogue " |
| 186 | "loops.")); |
| 187 | |
| 188 | static cl::opt<unsigned> EpilogueVectorizationMinVF( |
| 189 | "epilogue-vectorization-minimum-VF", cl::init(16), cl::Hidden, |
| 190 | cl::desc("Only loops with vectorization factor equal to or larger than " |
| 191 | "the specified value are considered for epilogue vectorization.")); |
| 192 | |
| 193 | /// Loops with a known constant trip count below this number are vectorized only |
| 194 | /// if no scalar iteration overheads are incurred. |
| 195 | static cl::opt<unsigned> TinyTripCountVectorThreshold( |
| 196 | "vectorizer-min-trip-count", cl::init(16), cl::Hidden, |
| 197 | cl::desc("Loops with a constant trip count that is smaller than this " |
| 198 | "value are vectorized only if no scalar iteration overheads " |
| 199 | "are incurred.")); |
| 200 | |
| 201 | static cl::opt<unsigned> PragmaVectorizeMemoryCheckThreshold( |
| 202 | "pragma-vectorize-memory-check-threshold", cl::init(128), cl::Hidden, |
| 203 | cl::desc("The maximum allowed number of runtime memory checks with a " |
| 204 | "vectorize(enable) pragma.")); |
| 205 | |
| 206 | // Option prefer-predicate-over-epilogue indicates that an epilogue is undesired, |
| 207 | // that predication is preferred, and this lists all options. I.e., the |
| 208 | // vectorizer will try to fold the tail-loop (epilogue) into the vector body |
| 209 | // and predicate the instructions accordingly. If tail-folding fails, there are |
| 210 | // different fallback strategies depending on these values: |
| 211 | namespace PreferPredicateTy { |
| 212 | enum Option { |
| 213 | ScalarEpilogue = 0, |
| 214 | PredicateElseScalarEpilogue, |
| 215 | PredicateOrDontVectorize |
| 216 | }; |
| 217 | } // namespace PreferPredicateTy |
| 218 | |
| 219 | static cl::opt<PreferPredicateTy::Option> PreferPredicateOverEpilogue( |
| 220 | "prefer-predicate-over-epilogue", |
| 221 | cl::init(PreferPredicateTy::ScalarEpilogue), |
| 222 | cl::Hidden, |
| 223 | cl::desc("Tail-folding and predication preferences over creating a scalar " |
| 224 | "epilogue loop."), |
| 225 | cl::values(clEnumValN(PreferPredicateTy::ScalarEpilogue,llvm::cl::OptionEnumValue { "scalar-epilogue", int(PreferPredicateTy ::ScalarEpilogue), "Don't tail-predicate loops, create scalar epilogue" } |
| 226 | "scalar-epilogue",llvm::cl::OptionEnumValue { "scalar-epilogue", int(PreferPredicateTy ::ScalarEpilogue), "Don't tail-predicate loops, create scalar epilogue" } |
| 227 | "Don't tail-predicate loops, create scalar epilogue")llvm::cl::OptionEnumValue { "scalar-epilogue", int(PreferPredicateTy ::ScalarEpilogue), "Don't tail-predicate loops, create scalar epilogue" }, |
| 228 | clEnumValN(PreferPredicateTy::PredicateElseScalarEpilogue,llvm::cl::OptionEnumValue { "predicate-else-scalar-epilogue", int(PreferPredicateTy::PredicateElseScalarEpilogue), "prefer tail-folding, create scalar epilogue if tail " "folding fails." } |
| 229 | "predicate-else-scalar-epilogue",llvm::cl::OptionEnumValue { "predicate-else-scalar-epilogue", int(PreferPredicateTy::PredicateElseScalarEpilogue), "prefer tail-folding, create scalar epilogue if tail " "folding fails." } |
| 230 | "prefer tail-folding, create scalar epilogue if tail "llvm::cl::OptionEnumValue { "predicate-else-scalar-epilogue", int(PreferPredicateTy::PredicateElseScalarEpilogue), "prefer tail-folding, create scalar epilogue if tail " "folding fails." } |
| 231 | "folding fails.")llvm::cl::OptionEnumValue { "predicate-else-scalar-epilogue", int(PreferPredicateTy::PredicateElseScalarEpilogue), "prefer tail-folding, create scalar epilogue if tail " "folding fails." }, |
| 232 | clEnumValN(PreferPredicateTy::PredicateOrDontVectorize,llvm::cl::OptionEnumValue { "predicate-dont-vectorize", int(PreferPredicateTy ::PredicateOrDontVectorize), "prefers tail-folding, don't attempt vectorization if " "tail-folding fails." } |
| 233 | "predicate-dont-vectorize",llvm::cl::OptionEnumValue { "predicate-dont-vectorize", int(PreferPredicateTy ::PredicateOrDontVectorize), "prefers tail-folding, don't attempt vectorization if " "tail-folding fails." } |
| 234 | "prefers tail-folding, don't attempt vectorization if "llvm::cl::OptionEnumValue { "predicate-dont-vectorize", int(PreferPredicateTy ::PredicateOrDontVectorize), "prefers tail-folding, don't attempt vectorization if " "tail-folding fails." } |
| 235 | "tail-folding fails.")llvm::cl::OptionEnumValue { "predicate-dont-vectorize", int(PreferPredicateTy ::PredicateOrDontVectorize), "prefers tail-folding, don't attempt vectorization if " "tail-folding fails." })); |
| 236 | |
| 237 | static cl::opt<bool> MaximizeBandwidth( |
| 238 | "vectorizer-maximize-bandwidth", cl::init(false), cl::Hidden, |
| 239 | cl::desc("Maximize bandwidth when selecting vectorization factor which " |
| 240 | "will be determined by the smallest type in loop.")); |
| 241 | |
| 242 | static cl::opt<bool> EnableInterleavedMemAccesses( |
| 243 | "enable-interleaved-mem-accesses", cl::init(false), cl::Hidden, |
| 244 | cl::desc("Enable vectorization on interleaved memory accesses in a loop")); |
| 245 | |
| 246 | /// An interleave-group may need masking if it resides in a block that needs |
| 247 | /// predication, or in order to mask away gaps. |
| 248 | static cl::opt<bool> EnableMaskedInterleavedMemAccesses( |
| 249 | "enable-masked-interleaved-mem-accesses", cl::init(false), cl::Hidden, |
| 250 | cl::desc("Enable vectorization on masked interleaved memory accesses in a loop")); |
| 251 | |
| 252 | static cl::opt<unsigned> TinyTripCountInterleaveThreshold( |
| 253 | "tiny-trip-count-interleave-threshold", cl::init(128), cl::Hidden, |
| 254 | cl::desc("We don't interleave loops with a estimated constant trip count " |
| 255 | "below this number")); |
| 256 | |
| 257 | static cl::opt<unsigned> ForceTargetNumScalarRegs( |
| 258 | "force-target-num-scalar-regs", cl::init(0), cl::Hidden, |
| 259 | cl::desc("A flag that overrides the target's number of scalar registers.")); |
| 260 | |
| 261 | static cl::opt<unsigned> ForceTargetNumVectorRegs( |
| 262 | "force-target-num-vector-regs", cl::init(0), cl::Hidden, |
| 263 | cl::desc("A flag that overrides the target's number of vector registers.")); |
| 264 | |
| 265 | static cl::opt<unsigned> ForceTargetMaxScalarInterleaveFactor( |
| 266 | "force-target-max-scalar-interleave", cl::init(0), cl::Hidden, |
| 267 | cl::desc("A flag that overrides the target's max interleave factor for " |
| 268 | "scalar loops.")); |
| 269 | |
| 270 | static cl::opt<unsigned> ForceTargetMaxVectorInterleaveFactor( |
| 271 | "force-target-max-vector-interleave", cl::init(0), cl::Hidden, |
| 272 | cl::desc("A flag that overrides the target's max interleave factor for " |
| 273 | "vectorized loops.")); |
| 274 | |
| 275 | static cl::opt<unsigned> ForceTargetInstructionCost( |
| 276 | "force-target-instruction-cost", cl::init(0), cl::Hidden, |
| 277 | cl::desc("A flag that overrides the target's expected cost for " |
| 278 | "an instruction to a single constant value. Mostly " |
| 279 | "useful for getting consistent testing.")); |
| 280 | |
| 281 | static cl::opt<bool> ForceTargetSupportsScalableVectors( |
| 282 | "force-target-supports-scalable-vectors", cl::init(false), cl::Hidden, |
| 283 | cl::desc( |
| 284 | "Pretend that scalable vectors are supported, even if the target does " |
| 285 | "not support them. This flag should only be used for testing.")); |
| 286 | |
| 287 | static cl::opt<unsigned> SmallLoopCost( |
| 288 | "small-loop-cost", cl::init(20), cl::Hidden, |
| 289 | cl::desc( |
| 290 | "The cost of a loop that is considered 'small' by the interleaver.")); |
| 291 | |
| 292 | static cl::opt<bool> LoopVectorizeWithBlockFrequency( |
| 293 | "loop-vectorize-with-block-frequency", cl::init(true), cl::Hidden, |
| 294 | cl::desc("Enable the use of the block frequency analysis to access PGO " |
| 295 | "heuristics minimizing code growth in cold regions and being more " |
| 296 | "aggressive in hot regions.")); |
| 297 | |
| 298 | // Runtime interleave loops for load/store throughput. |
| 299 | static cl::opt<bool> EnableLoadStoreRuntimeInterleave( |
| 300 | "enable-loadstore-runtime-interleave", cl::init(true), cl::Hidden, |
| 301 | cl::desc( |
| 302 | "Enable runtime interleaving until load/store ports are saturated")); |
| 303 | |
| 304 | /// Interleave small loops with scalar reductions. |
| 305 | static cl::opt<bool> InterleaveSmallLoopScalarReduction( |
| 306 | "interleave-small-loop-scalar-reduction", cl::init(false), cl::Hidden, |
| 307 | cl::desc("Enable interleaving for loops with small iteration counts that " |
| 308 | "contain scalar reductions to expose ILP.")); |
| 309 | |
| 310 | /// The number of stores in a loop that are allowed to need predication. |
| 311 | static cl::opt<unsigned> NumberOfStoresToPredicate( |
| 312 | "vectorize-num-stores-pred", cl::init(1), cl::Hidden, |
| 313 | cl::desc("Max number of stores to be predicated behind an if.")); |
| 314 | |
| 315 | static cl::opt<bool> EnableIndVarRegisterHeur( |
| 316 | "enable-ind-var-reg-heur", cl::init(true), cl::Hidden, |
| 317 | cl::desc("Count the induction variable only once when interleaving")); |
| 318 | |
| 319 | static cl::opt<bool> EnableCondStoresVectorization( |
| 320 | "enable-cond-stores-vec", cl::init(true), cl::Hidden, |
| 321 | cl::desc("Enable if predication of stores during vectorization.")); |
| 322 | |
| 323 | static cl::opt<unsigned> MaxNestedScalarReductionIC( |
| 324 | "max-nested-scalar-reduction-interleave", cl::init(2), cl::Hidden, |
| 325 | cl::desc("The maximum interleave count to use when interleaving a scalar " |
| 326 | "reduction in a nested loop.")); |
| 327 | |
| 328 | static cl::opt<bool> |
| 329 | PreferInLoopReductions("prefer-inloop-reductions", cl::init(false), |
| 330 | cl::Hidden, |
| 331 | cl::desc("Prefer in-loop vector reductions, " |
| 332 | "overriding the targets preference.")); |
| 333 | |
| 334 | static cl::opt<bool> ForceOrderedReductions( |
| 335 | "force-ordered-reductions", cl::init(false), cl::Hidden, |
| 336 | cl::desc("Enable the vectorisation of loops with in-order (strict) " |
| 337 | "FP reductions")); |
| 338 | |
| 339 | static cl::opt<bool> PreferPredicatedReductionSelect( |
| 340 | "prefer-predicated-reduction-select", cl::init(false), cl::Hidden, |
| 341 | cl::desc( |
| 342 | "Prefer predicating a reduction operation over an after loop select.")); |
| 343 | |
| 344 | cl::opt<bool> EnableVPlanNativePath( |
| 345 | "enable-vplan-native-path", cl::init(false), cl::Hidden, |
| 346 | cl::desc("Enable VPlan-native vectorization path with " |
| 347 | "support for outer loop vectorization.")); |
| 348 | |
| 349 | // FIXME: Remove this switch once we have divergence analysis. Currently we |
| 350 | // assume divergent non-backedge branches when this switch is true. |
| 351 | cl::opt<bool> EnableVPlanPredication( |
| 352 | "enable-vplan-predication", cl::init(false), cl::Hidden, |
| 353 | cl::desc("Enable VPlan-native vectorization path predicator with " |
| 354 | "support for outer loop vectorization.")); |
| 355 | |
| 356 | // This flag enables the stress testing of the VPlan H-CFG construction in the |
| 357 | // VPlan-native vectorization path. It must be used in conjuction with |
| 358 | // -enable-vplan-native-path. -vplan-verify-hcfg can also be used to enable the |
| 359 | // verification of the H-CFGs built. |
| 360 | static cl::opt<bool> VPlanBuildStressTest( |
| 361 | "vplan-build-stress-test", cl::init(false), cl::Hidden, |
| 362 | cl::desc( |
| 363 | "Build VPlan for every supported loop nest in the function and bail " |
| 364 | "out right after the build (stress test the VPlan H-CFG construction " |
| 365 | "in the VPlan-native vectorization path).")); |
| 366 | |
| 367 | cl::opt<bool> llvm::EnableLoopInterleaving( |
| 368 | "interleave-loops", cl::init(true), cl::Hidden, |
| 369 | cl::desc("Enable loop interleaving in Loop vectorization passes")); |
| 370 | cl::opt<bool> llvm::EnableLoopVectorization( |
| 371 | "vectorize-loops", cl::init(true), cl::Hidden, |
| 372 | cl::desc("Run the Loop vectorization passes")); |
| 373 | |
| 374 | cl::opt<bool> PrintVPlansInDotFormat( |
| 375 | "vplan-print-in-dot-format", cl::init(false), cl::Hidden, |
| 376 | cl::desc("Use dot format instead of plain text when dumping VPlans")); |
| 377 | |
| 378 | /// A helper function that returns true if the given type is irregular. The |
| 379 | /// type is irregular if its allocated size doesn't equal the store size of an |
| 380 | /// element of the corresponding vector type. |
| 381 | static bool hasIrregularType(Type *Ty, const DataLayout &DL) { |
| 382 | // Determine if an array of N elements of type Ty is "bitcast compatible" |
| 383 | // with a <N x Ty> vector. |
| 384 | // This is only true if there is no padding between the array elements. |
| 385 | return DL.getTypeAllocSizeInBits(Ty) != DL.getTypeSizeInBits(Ty); |
| 386 | } |
| 387 | |
| 388 | /// A helper function that returns the reciprocal of the block probability of |
| 389 | /// predicated blocks. If we return X, we are assuming the predicated block |
| 390 | /// will execute once for every X iterations of the loop header. |
| 391 | /// |
| 392 | /// TODO: We should use actual block probability here, if available. Currently, |
| 393 | /// we always assume predicated blocks have a 50% chance of executing. |
| 394 | static unsigned getReciprocalPredBlockProb() { return 2; } |
| 395 | |
| 396 | /// A helper function that returns an integer or floating-point constant with |
| 397 | /// value C. |
| 398 | static Constant *getSignedIntOrFpConstant(Type *Ty, int64_t C) { |
| 399 | return Ty->isIntegerTy() ? ConstantInt::getSigned(Ty, C) |
| 400 | : ConstantFP::get(Ty, C); |
| 401 | } |
| 402 | |
| 403 | /// Returns "best known" trip count for the specified loop \p L as defined by |
| 404 | /// the following procedure: |
| 405 | /// 1) Returns exact trip count if it is known. |
| 406 | /// 2) Returns expected trip count according to profile data if any. |
| 407 | /// 3) Returns upper bound estimate if it is known. |
| 408 | /// 4) Returns None if all of the above failed. |
| 409 | static Optional<unsigned> getSmallBestKnownTC(ScalarEvolution &SE, Loop *L) { |
| 410 | // Check if exact trip count is known. |
| 411 | if (unsigned ExpectedTC = SE.getSmallConstantTripCount(L)) |
| 412 | return ExpectedTC; |
| 413 | |
| 414 | // Check if there is an expected trip count available from profile data. |
| 415 | if (LoopVectorizeWithBlockFrequency) |
| 416 | if (auto EstimatedTC = getLoopEstimatedTripCount(L)) |
| 417 | return EstimatedTC; |
| 418 | |
| 419 | // Check if upper bound estimate is known. |
| 420 | if (unsigned ExpectedTC = SE.getSmallConstantMaxTripCount(L)) |
| 421 | return ExpectedTC; |
| 422 | |
| 423 | return None; |
| 424 | } |
| 425 | |
| 426 | // Forward declare GeneratedRTChecks. |
| 427 | class GeneratedRTChecks; |
| 428 | |
| 429 | namespace llvm { |
| 430 | |
| 431 | AnalysisKey ShouldRunExtraVectorPasses::Key; |
| 432 | |
| 433 | /// InnerLoopVectorizer vectorizes loops which contain only one basic |
| 434 | /// block to a specified vectorization factor (VF). |
| 435 | /// This class performs the widening of scalars into vectors, or multiple |
| 436 | /// scalars. This class also implements the following features: |
| 437 | /// * It inserts an epilogue loop for handling loops that don't have iteration |
| 438 | /// counts that are known to be a multiple of the vectorization factor. |
| 439 | /// * It handles the code generation for reduction variables. |
| 440 | /// * Scalarization (implementation using scalars) of un-vectorizable |
| 441 | /// instructions. |
| 442 | /// InnerLoopVectorizer does not perform any vectorization-legality |
| 443 | /// checks, and relies on the caller to check for the different legality |
| 444 | /// aspects. The InnerLoopVectorizer relies on the |
| 445 | /// LoopVectorizationLegality class to provide information about the induction |
| 446 | /// and reduction variables that were found to a given vectorization factor. |
| 447 | class InnerLoopVectorizer { |
| 448 | public: |
| 449 | InnerLoopVectorizer(Loop *OrigLoop, PredicatedScalarEvolution &PSE, |
| 450 | LoopInfo *LI, DominatorTree *DT, |
| 451 | const TargetLibraryInfo *TLI, |
| 452 | const TargetTransformInfo *TTI, AssumptionCache *AC, |
| 453 | OptimizationRemarkEmitter *ORE, ElementCount VecWidth, |
| 454 | unsigned UnrollFactor, LoopVectorizationLegality *LVL, |
| 455 | LoopVectorizationCostModel *CM, BlockFrequencyInfo *BFI, |
| 456 | ProfileSummaryInfo *PSI, GeneratedRTChecks &RTChecks) |
| 457 | : OrigLoop(OrigLoop), PSE(PSE), LI(LI), DT(DT), TLI(TLI), TTI(TTI), |
| 458 | AC(AC), ORE(ORE), VF(VecWidth), UF(UnrollFactor), |
| 459 | Builder(PSE.getSE()->getContext()), Legal(LVL), Cost(CM), BFI(BFI), |
| 460 | PSI(PSI), RTChecks(RTChecks) { |
| 461 | // Query this against the original loop and save it here because the profile |
| 462 | // of the original loop header may change as the transformation happens. |
| 463 | OptForSizeBasedOnProfile = llvm::shouldOptimizeForSize( |
| 464 | OrigLoop->getHeader(), PSI, BFI, PGSOQueryType::IRPass); |
| 465 | } |
| 466 | |
| 467 | virtual ~InnerLoopVectorizer() = default; |
| 468 | |
| 469 | /// Create a new empty loop that will contain vectorized instructions later |
| 470 | /// on, while the old loop will be used as the scalar remainder. Control flow |
| 471 | /// is generated around the vectorized (and scalar epilogue) loops consisting |
| 472 | /// of various checks and bypasses. Return the pre-header block of the new |
| 473 | /// loop and the start value for the canonical induction, if it is != 0. The |
| 474 | /// latter is the case when vectorizing the epilogue loop. In the case of |
| 475 | /// epilogue vectorization, this function is overriden to handle the more |
| 476 | /// complex control flow around the loops. |
| 477 | virtual std::pair<BasicBlock *, Value *> createVectorizedLoopSkeleton(); |
| 478 | |
| 479 | /// Widen a single call instruction within the innermost loop. |
| 480 | void widenCallInstruction(CallInst &I, VPValue *Def, VPUser &ArgOperands, |
| 481 | VPTransformState &State); |
| 482 | |
| 483 | /// Fix the vectorized code, taking care of header phi's, live-outs, and more. |
| 484 | void fixVectorizedLoop(VPTransformState &State); |
| 485 | |
| 486 | // Return true if any runtime check is added. |
| 487 | bool areSafetyChecksAdded() { return AddedSafetyChecks; } |
| 488 | |
| 489 | /// A type for vectorized values in the new loop. Each value from the |
| 490 | /// original loop, when vectorized, is represented by UF vector values in the |
| 491 | /// new unrolled loop, where UF is the unroll factor. |
| 492 | using VectorParts = SmallVector<Value *, 2>; |
| 493 | |
| 494 | /// Vectorize a single first-order recurrence or pointer induction PHINode in |
| 495 | /// a block. This method handles the induction variable canonicalization. It |
| 496 | /// supports both VF = 1 for unrolled loops and arbitrary length vectors. |
| 497 | void widenPHIInstruction(Instruction *PN, VPWidenPHIRecipe *PhiR, |
| 498 | VPTransformState &State); |
| 499 | |
| 500 | /// A helper function to scalarize a single Instruction in the innermost loop. |
| 501 | /// Generates a sequence of scalar instances for each lane between \p MinLane |
| 502 | /// and \p MaxLane, times each part between \p MinPart and \p MaxPart, |
| 503 | /// inclusive. Uses the VPValue operands from \p RepRecipe instead of \p |
| 504 | /// Instr's operands. |
| 505 | void scalarizeInstruction(Instruction *Instr, VPReplicateRecipe *RepRecipe, |
| 506 | const VPIteration &Instance, bool IfPredicateInstr, |
| 507 | VPTransformState &State); |
| 508 | |
| 509 | /// Widen an integer or floating-point induction variable \p IV. If \p Trunc |
| 510 | /// is provided, the integer induction variable will first be truncated to |
| 511 | /// the corresponding type. \p CanonicalIV is the scalar value generated for |
| 512 | /// the canonical induction variable. |
| 513 | void widenIntOrFpInduction(PHINode *IV, VPWidenIntOrFpInductionRecipe *Def, |
| 514 | VPTransformState &State, Value *CanonicalIV); |
| 515 | |
| 516 | /// Construct the vector value of a scalarized value \p V one lane at a time. |
| 517 | void packScalarIntoVectorValue(VPValue *Def, const VPIteration &Instance, |
| 518 | VPTransformState &State); |
| 519 | |
| 520 | /// Try to vectorize interleaved access group \p Group with the base address |
| 521 | /// given in \p Addr, optionally masking the vector operations if \p |
| 522 | /// BlockInMask is non-null. Use \p State to translate given VPValues to IR |
| 523 | /// values in the vectorized loop. |
| 524 | void vectorizeInterleaveGroup(const InterleaveGroup<Instruction> *Group, |
| 525 | ArrayRef<VPValue *> VPDefs, |
| 526 | VPTransformState &State, VPValue *Addr, |
| 527 | ArrayRef<VPValue *> StoredValues, |
| 528 | VPValue *BlockInMask = nullptr); |
| 529 | |
| 530 | /// Set the debug location in the builder \p Ptr using the debug location in |
| 531 | /// \p V. If \p Ptr is None then it uses the class member's Builder. |
| 532 | void setDebugLocFromInst(const Value *V, |
| 533 | Optional<IRBuilder<> *> CustomBuilder = None); |
| 534 | |
| 535 | /// Fix the non-induction PHIs in the OrigPHIsToFix vector. |
| 536 | void fixNonInductionPHIs(VPTransformState &State); |
| 537 | |
| 538 | /// Returns true if the reordering of FP operations is not allowed, but we are |
| 539 | /// able to vectorize with strict in-order reductions for the given RdxDesc. |
| 540 | bool useOrderedReductions(const RecurrenceDescriptor &RdxDesc); |
| 541 | |
| 542 | /// Create a broadcast instruction. This method generates a broadcast |
| 543 | /// instruction (shuffle) for loop invariant values and for the induction |
| 544 | /// value. If this is the induction variable then we extend it to N, N+1, ... |
| 545 | /// this is needed because each iteration in the loop corresponds to a SIMD |
| 546 | /// element. |
| 547 | virtual Value *getBroadcastInstrs(Value *V); |
| 548 | |
| 549 | /// Add metadata from one instruction to another. |
| 550 | /// |
| 551 | /// This includes both the original MDs from \p From and additional ones (\see |
| 552 | /// addNewMetadata). Use this for *newly created* instructions in the vector |
| 553 | /// loop. |
| 554 | void addMetadata(Instruction *To, Instruction *From); |
| 555 | |
| 556 | /// Similar to the previous function but it adds the metadata to a |
| 557 | /// vector of instructions. |
| 558 | void addMetadata(ArrayRef<Value *> To, Instruction *From); |
| 559 | |
| 560 | // Returns the resume value (bc.merge.rdx) for a reduction as |
| 561 | // generated by fixReduction. |
| 562 | PHINode *getReductionResumeValue(const RecurrenceDescriptor &RdxDesc); |
| 563 | |
| 564 | protected: |
| 565 | friend class LoopVectorizationPlanner; |
| 566 | |
| 567 | /// A small list of PHINodes. |
| 568 | using PhiVector = SmallVector<PHINode *, 4>; |
| 569 | |
| 570 | /// A type for scalarized values in the new loop. Each value from the |
| 571 | /// original loop, when scalarized, is represented by UF x VF scalar values |
| 572 | /// in the new unrolled loop, where UF is the unroll factor and VF is the |
| 573 | /// vectorization factor. |
| 574 | using ScalarParts = SmallVector<SmallVector<Value *, 4>, 2>; |
| 575 | |
| 576 | /// Set up the values of the IVs correctly when exiting the vector loop. |
| 577 | void fixupIVUsers(PHINode *OrigPhi, const InductionDescriptor &II, |
| 578 | Value *CountRoundDown, Value *EndValue, |
| 579 | BasicBlock *MiddleBlock); |
| 580 | |
| 581 | /// Introduce a conditional branch (on true, condition to be set later) at the |
| 582 | /// end of the header=latch connecting it to itself (across the backedge) and |
| 583 | /// to the exit block of \p L. |
| 584 | void createHeaderBranch(Loop *L); |
| 585 | |
| 586 | /// Handle all cross-iteration phis in the header. |
| 587 | void fixCrossIterationPHIs(VPTransformState &State); |
| 588 | |
| 589 | /// Create the exit value of first order recurrences in the middle block and |
| 590 | /// update their users. |
| 591 | void fixFirstOrderRecurrence(VPFirstOrderRecurrencePHIRecipe *PhiR, |
| 592 | VPTransformState &State); |
| 593 | |
| 594 | /// Create code for the loop exit value of the reduction. |
| 595 | void fixReduction(VPReductionPHIRecipe *Phi, VPTransformState &State); |
| 596 | |
| 597 | /// Clear NSW/NUW flags from reduction instructions if necessary. |
| 598 | void clearReductionWrapFlags(const RecurrenceDescriptor &RdxDesc, |
| 599 | VPTransformState &State); |
| 600 | |
| 601 | /// Fixup the LCSSA phi nodes in the unique exit block. This simply |
| 602 | /// means we need to add the appropriate incoming value from the middle |
| 603 | /// block as exiting edges from the scalar epilogue loop (if present) are |
| 604 | /// already in place, and we exit the vector loop exclusively to the middle |
| 605 | /// block. |
| 606 | void fixLCSSAPHIs(VPTransformState &State); |
| 607 | |
| 608 | /// Iteratively sink the scalarized operands of a predicated instruction into |
| 609 | /// the block that was created for it. |
| 610 | void sinkScalarOperands(Instruction *PredInst); |
| 611 | |
| 612 | /// Shrinks vector element sizes to the smallest bitwidth they can be legally |
| 613 | /// represented as. |
| 614 | void truncateToMinimalBitwidths(VPTransformState &State); |
| 615 | |
| 616 | /// Compute scalar induction steps. \p ScalarIV is the scalar induction |
| 617 | /// variable on which to base the steps, \p Step is the size of the step, and |
| 618 | /// \p EntryVal is the value from the original loop that maps to the steps. |
| 619 | /// Note that \p EntryVal doesn't have to be an induction variable - it |
| 620 | /// can also be a truncate instruction. |
| 621 | void buildScalarSteps(Value *ScalarIV, Value *Step, Instruction *EntryVal, |
| 622 | const InductionDescriptor &ID, VPValue *Def, |
| 623 | VPTransformState &State); |
| 624 | |
| 625 | /// Create a vector induction phi node based on an existing scalar one. \p |
| 626 | /// EntryVal is the value from the original loop that maps to the vector phi |
| 627 | /// node, and \p Step is the loop-invariant step. If \p EntryVal is a |
| 628 | /// truncate instruction, instead of widening the original IV, we widen a |
| 629 | /// version of the IV truncated to \p EntryVal's type. |
| 630 | void createVectorIntOrFpInductionPHI(const InductionDescriptor &II, |
| 631 | Value *Step, Value *Start, |
| 632 | Instruction *EntryVal, VPValue *Def, |
| 633 | VPTransformState &State); |
| 634 | |
| 635 | /// Returns (and creates if needed) the original loop trip count. |
| 636 | Value *getOrCreateTripCount(Loop *NewLoop); |
| 637 | |
| 638 | /// Returns (and creates if needed) the trip count of the widened loop. |
| 639 | Value *getOrCreateVectorTripCount(Loop *NewLoop); |
| 640 | |
| 641 | /// Returns a bitcasted value to the requested vector type. |
| 642 | /// Also handles bitcasts of vector<float> <-> vector<pointer> types. |
| 643 | Value *createBitOrPointerCast(Value *V, VectorType *DstVTy, |
| 644 | const DataLayout &DL); |
| 645 | |
| 646 | /// Emit a bypass check to see if the vector trip count is zero, including if |
| 647 | /// it overflows. |
| 648 | void emitMinimumIterationCountCheck(Loop *L, BasicBlock *Bypass); |
| 649 | |
| 650 | /// Emit a bypass check to see if all of the SCEV assumptions we've |
| 651 | /// had to make are correct. Returns the block containing the checks or |
| 652 | /// nullptr if no checks have been added. |
| 653 | BasicBlock *emitSCEVChecks(Loop *L, BasicBlock *Bypass); |
| 654 | |
| 655 | /// Emit bypass checks to check any memory assumptions we may have made. |
| 656 | /// Returns the block containing the checks or nullptr if no checks have been |
| 657 | /// added. |
| 658 | BasicBlock *emitMemRuntimeChecks(Loop *L, BasicBlock *Bypass); |
| 659 | |
| 660 | /// Compute the transformed value of Index at offset StartValue using step |
| 661 | /// StepValue. |
| 662 | /// For integer induction, returns StartValue + Index * StepValue. |
| 663 | /// For pointer induction, returns StartValue[Index * StepValue]. |
| 664 | /// FIXME: The newly created binary instructions should contain nsw/nuw |
| 665 | /// flags, which can be found from the original scalar operations. |
| 666 | Value *emitTransformedIndex(IRBuilder<> &B, Value *Index, ScalarEvolution *SE, |
| 667 | const DataLayout &DL, |
| 668 | const InductionDescriptor &ID, |
| 669 | BasicBlock *VectorHeader) const; |
| 670 | |
| 671 | /// Emit basic blocks (prefixed with \p Prefix) for the iteration check, |
| 672 | /// vector loop preheader, middle block and scalar preheader. Also |
| 673 | /// allocate a loop object for the new vector loop and return it. |
| 674 | Loop *createVectorLoopSkeleton(StringRef Prefix); |
| 675 | |
| 676 | /// Create new phi nodes for the induction variables to resume iteration count |
| 677 | /// in the scalar epilogue, from where the vectorized loop left off. |
| 678 | /// In cases where the loop skeleton is more complicated (eg. epilogue |
| 679 | /// vectorization) and the resume values can come from an additional bypass |
| 680 | /// block, the \p AdditionalBypass pair provides information about the bypass |
| 681 | /// block and the end value on the edge from bypass to this loop. |
| 682 | void createInductionResumeValues( |
| 683 | Loop *L, |
| 684 | std::pair<BasicBlock *, Value *> AdditionalBypass = {nullptr, nullptr}); |
| 685 | |
| 686 | /// Complete the loop skeleton by adding debug MDs, creating appropriate |
| 687 | /// conditional branches in the middle block, preparing the builder and |
| 688 | /// running the verifier. Take in the vector loop \p L as argument, and return |
| 689 | /// the preheader of the completed vector loop. |
| 690 | BasicBlock *completeLoopSkeleton(Loop *L, MDNode *OrigLoopID); |
| 691 | |
| 692 | /// Add additional metadata to \p To that was not present on \p Orig. |
| 693 | /// |
| 694 | /// Currently this is used to add the noalias annotations based on the |
| 695 | /// inserted memchecks. Use this for instructions that are *cloned* into the |
| 696 | /// vector loop. |
| 697 | void addNewMetadata(Instruction *To, const Instruction *Orig); |
| 698 | |
| 699 | /// Collect poison-generating recipes that may generate a poison value that is |
| 700 | /// used after vectorization, even when their operands are not poison. Those |
| 701 | /// recipes meet the following conditions: |
| 702 | /// * Contribute to the address computation of a recipe generating a widen |
| 703 | /// memory load/store (VPWidenMemoryInstructionRecipe or |
| 704 | /// VPInterleaveRecipe). |
| 705 | /// * Such a widen memory load/store has at least one underlying Instruction |
| 706 | /// that is in a basic block that needs predication and after vectorization |
| 707 | /// the generated instruction won't be predicated. |
| 708 | void collectPoisonGeneratingRecipes(VPTransformState &State); |
| 709 | |
| 710 | /// Allow subclasses to override and print debug traces before/after vplan |
| 711 | /// execution, when trace information is requested. |
| 712 | virtual void printDebugTracesAtStart(){}; |
| 713 | virtual void printDebugTracesAtEnd(){}; |
| 714 | |
| 715 | /// The original loop. |
| 716 | Loop *OrigLoop; |
| 717 | |
| 718 | /// A wrapper around ScalarEvolution used to add runtime SCEV checks. Applies |
| 719 | /// dynamic knowledge to simplify SCEV expressions and converts them to a |
| 720 | /// more usable form. |
| 721 | PredicatedScalarEvolution &PSE; |
| 722 | |
| 723 | /// Loop Info. |
| 724 | LoopInfo *LI; |
| 725 | |
| 726 | /// Dominator Tree. |
| 727 | DominatorTree *DT; |
| 728 | |
| 729 | /// Alias Analysis. |
| 730 | AAResults *AA; |
| 731 | |
| 732 | /// Target Library Info. |
| 733 | const TargetLibraryInfo *TLI; |
| 734 | |
| 735 | /// Target Transform Info. |
| 736 | const TargetTransformInfo *TTI; |
| 737 | |
| 738 | /// Assumption Cache. |
| 739 | AssumptionCache *AC; |
| 740 | |
| 741 | /// Interface to emit optimization remarks. |
| 742 | OptimizationRemarkEmitter *ORE; |
| 743 | |
| 744 | /// LoopVersioning. It's only set up (non-null) if memchecks were |
| 745 | /// used. |
| 746 | /// |
| 747 | /// This is currently only used to add no-alias metadata based on the |
| 748 | /// memchecks. The actually versioning is performed manually. |
| 749 | std::unique_ptr<LoopVersioning> LVer; |
| 750 | |
| 751 | /// The vectorization SIMD factor to use. Each vector will have this many |
| 752 | /// vector elements. |
| 753 | ElementCount VF; |
| 754 | |
| 755 | /// The vectorization unroll factor to use. Each scalar is vectorized to this |
| 756 | /// many different vector instructions. |
| 757 | unsigned UF; |
| 758 | |
| 759 | /// The builder that we use |
| 760 | IRBuilder<> Builder; |
| 761 | |
| 762 | // --- Vectorization state --- |
| 763 | |
| 764 | /// The vector-loop preheader. |
| 765 | BasicBlock *LoopVectorPreHeader; |
| 766 | |
| 767 | /// The scalar-loop preheader. |
| 768 | BasicBlock *LoopScalarPreHeader; |
| 769 | |
| 770 | /// Middle Block between the vector and the scalar. |
| 771 | BasicBlock *LoopMiddleBlock; |
| 772 | |
| 773 | /// The unique ExitBlock of the scalar loop if one exists. Note that |
| 774 | /// there can be multiple exiting edges reaching this block. |
| 775 | BasicBlock *LoopExitBlock; |
| 776 | |
| 777 | /// The vector loop body. |
| 778 | BasicBlock *LoopVectorBody; |
| 779 | |
| 780 | /// The scalar loop body. |
| 781 | BasicBlock *LoopScalarBody; |
| 782 | |
| 783 | /// A list of all bypass blocks. The first block is the entry of the loop. |
| 784 | SmallVector<BasicBlock *, 4> LoopBypassBlocks; |
| 785 | |
| 786 | /// Store instructions that were predicated. |
| 787 | SmallVector<Instruction *, 4> PredicatedInstructions; |
| 788 | |
| 789 | /// Trip count of the original loop. |
| 790 | Value *TripCount = nullptr; |
| 791 | |
| 792 | /// Trip count of the widened loop (TripCount - TripCount % (VF*UF)) |
| 793 | Value *VectorTripCount = nullptr; |
| 794 | |
| 795 | /// The legality analysis. |
| 796 | LoopVectorizationLegality *Legal; |
| 797 | |
| 798 | /// The profitablity analysis. |
| 799 | LoopVectorizationCostModel *Cost; |
| 800 | |
| 801 | // Record whether runtime checks are added. |
| 802 | bool AddedSafetyChecks = false; |
| 803 | |
| 804 | // Holds the end values for each induction variable. We save the end values |
| 805 | // so we can later fix-up the external users of the induction variables. |
| 806 | DenseMap<PHINode *, Value *> IVEndValues; |
| 807 | |
| 808 | // Vector of original scalar PHIs whose corresponding widened PHIs need to be |
| 809 | // fixed up at the end of vector code generation. |
| 810 | SmallVector<PHINode *, 8> OrigPHIsToFix; |
| 811 | |
| 812 | /// BFI and PSI are used to check for profile guided size optimizations. |
| 813 | BlockFrequencyInfo *BFI; |
| 814 | ProfileSummaryInfo *PSI; |
| 815 | |
| 816 | // Whether this loop should be optimized for size based on profile guided size |
| 817 | // optimizatios. |
| 818 | bool OptForSizeBasedOnProfile; |
| 819 | |
| 820 | /// Structure to hold information about generated runtime checks, responsible |
| 821 | /// for cleaning the checks, if vectorization turns out unprofitable. |
| 822 | GeneratedRTChecks &RTChecks; |
| 823 | |
| 824 | // Holds the resume values for reductions in the loops, used to set the |
| 825 | // correct start value of reduction PHIs when vectorizing the epilogue. |
| 826 | SmallMapVector<const RecurrenceDescriptor *, PHINode *, 4> |
| 827 | ReductionResumeValues; |
| 828 | }; |
| 829 | |
| 830 | class InnerLoopUnroller : public InnerLoopVectorizer { |
| 831 | public: |
| 832 | InnerLoopUnroller(Loop *OrigLoop, PredicatedScalarEvolution &PSE, |
| 833 | LoopInfo *LI, DominatorTree *DT, |
| 834 | const TargetLibraryInfo *TLI, |
| 835 | const TargetTransformInfo *TTI, AssumptionCache *AC, |
| 836 | OptimizationRemarkEmitter *ORE, unsigned UnrollFactor, |
| 837 | LoopVectorizationLegality *LVL, |
| 838 | LoopVectorizationCostModel *CM, BlockFrequencyInfo *BFI, |
| 839 | ProfileSummaryInfo *PSI, GeneratedRTChecks &Check) |
| 840 | : InnerLoopVectorizer(OrigLoop, PSE, LI, DT, TLI, TTI, AC, ORE, |
| 841 | ElementCount::getFixed(1), UnrollFactor, LVL, CM, |
| 842 | BFI, PSI, Check) {} |
| 843 | |
| 844 | private: |
| 845 | Value *getBroadcastInstrs(Value *V) override; |
| 846 | }; |
| 847 | |
| 848 | /// Encapsulate information regarding vectorization of a loop and its epilogue. |
| 849 | /// This information is meant to be updated and used across two stages of |
| 850 | /// epilogue vectorization. |
| 851 | struct EpilogueLoopVectorizationInfo { |
| 852 | ElementCount MainLoopVF = ElementCount::getFixed(0); |
| 853 | unsigned MainLoopUF = 0; |
| 854 | ElementCount EpilogueVF = ElementCount::getFixed(0); |
| 855 | unsigned EpilogueUF = 0; |
| 856 | BasicBlock *MainLoopIterationCountCheck = nullptr; |
| 857 | BasicBlock *EpilogueIterationCountCheck = nullptr; |
| 858 | BasicBlock *SCEVSafetyCheck = nullptr; |
| 859 | BasicBlock *MemSafetyCheck = nullptr; |
| 860 | Value *TripCount = nullptr; |
| 861 | Value *VectorTripCount = nullptr; |
| 862 | |
| 863 | EpilogueLoopVectorizationInfo(ElementCount MVF, unsigned MUF, |
| 864 | ElementCount EVF, unsigned EUF) |
| 865 | : MainLoopVF(MVF), MainLoopUF(MUF), EpilogueVF(EVF), EpilogueUF(EUF) { |
| 866 | assert(EUF == 1 &&(static_cast <bool> (EUF == 1 && "A high UF for the epilogue loop is likely not beneficial." ) ? void (0) : __assert_fail ("EUF == 1 && \"A high UF for the epilogue loop is likely not beneficial.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 867, __extension__ __PRETTY_FUNCTION__)) |
| 867 | "A high UF for the epilogue loop is likely not beneficial.")(static_cast <bool> (EUF == 1 && "A high UF for the epilogue loop is likely not beneficial." ) ? void (0) : __assert_fail ("EUF == 1 && \"A high UF for the epilogue loop is likely not beneficial.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 867, __extension__ __PRETTY_FUNCTION__)); |
| 868 | } |
| 869 | }; |
| 870 | |
| 871 | /// An extension of the inner loop vectorizer that creates a skeleton for a |
| 872 | /// vectorized loop that has its epilogue (residual) also vectorized. |
| 873 | /// The idea is to run the vplan on a given loop twice, firstly to setup the |
| 874 | /// skeleton and vectorize the main loop, and secondly to complete the skeleton |
| 875 | /// from the first step and vectorize the epilogue. This is achieved by |
| 876 | /// deriving two concrete strategy classes from this base class and invoking |
| 877 | /// them in succession from the loop vectorizer planner. |
| 878 | class InnerLoopAndEpilogueVectorizer : public InnerLoopVectorizer { |
| 879 | public: |
| 880 | InnerLoopAndEpilogueVectorizer( |
| 881 | Loop *OrigLoop, PredicatedScalarEvolution &PSE, LoopInfo *LI, |
| 882 | DominatorTree *DT, const TargetLibraryInfo *TLI, |
| 883 | const TargetTransformInfo *TTI, AssumptionCache *AC, |
| 884 | OptimizationRemarkEmitter *ORE, EpilogueLoopVectorizationInfo &EPI, |
| 885 | LoopVectorizationLegality *LVL, llvm::LoopVectorizationCostModel *CM, |
| 886 | BlockFrequencyInfo *BFI, ProfileSummaryInfo *PSI, |
| 887 | GeneratedRTChecks &Checks) |
| 888 | : InnerLoopVectorizer(OrigLoop, PSE, LI, DT, TLI, TTI, AC, ORE, |
| 889 | EPI.MainLoopVF, EPI.MainLoopUF, LVL, CM, BFI, PSI, |
| 890 | Checks), |
| 891 | EPI(EPI) {} |
| 892 | |
| 893 | // Override this function to handle the more complex control flow around the |
| 894 | // three loops. |
| 895 | std::pair<BasicBlock *, Value *> |
| 896 | createVectorizedLoopSkeleton() final override { |
| 897 | return createEpilogueVectorizedLoopSkeleton(); |
| 898 | } |
| 899 | |
| 900 | /// The interface for creating a vectorized skeleton using one of two |
| 901 | /// different strategies, each corresponding to one execution of the vplan |
| 902 | /// as described above. |
| 903 | virtual std::pair<BasicBlock *, Value *> |
| 904 | createEpilogueVectorizedLoopSkeleton() = 0; |
| 905 | |
| 906 | /// Holds and updates state information required to vectorize the main loop |
| 907 | /// and its epilogue in two separate passes. This setup helps us avoid |
| 908 | /// regenerating and recomputing runtime safety checks. It also helps us to |
| 909 | /// shorten the iteration-count-check path length for the cases where the |
| 910 | /// iteration count of the loop is so small that the main vector loop is |
| 911 | /// completely skipped. |
| 912 | EpilogueLoopVectorizationInfo &EPI; |
| 913 | }; |
| 914 | |
| 915 | /// A specialized derived class of inner loop vectorizer that performs |
| 916 | /// vectorization of *main* loops in the process of vectorizing loops and their |
| 917 | /// epilogues. |
| 918 | class EpilogueVectorizerMainLoop : public InnerLoopAndEpilogueVectorizer { |
| 919 | public: |
| 920 | EpilogueVectorizerMainLoop( |
| 921 | Loop *OrigLoop, PredicatedScalarEvolution &PSE, LoopInfo *LI, |
| 922 | DominatorTree *DT, const TargetLibraryInfo *TLI, |
| 923 | const TargetTransformInfo *TTI, AssumptionCache *AC, |
| 924 | OptimizationRemarkEmitter *ORE, EpilogueLoopVectorizationInfo &EPI, |
| 925 | LoopVectorizationLegality *LVL, llvm::LoopVectorizationCostModel *CM, |
| 926 | BlockFrequencyInfo *BFI, ProfileSummaryInfo *PSI, |
| 927 | GeneratedRTChecks &Check) |
| 928 | : InnerLoopAndEpilogueVectorizer(OrigLoop, PSE, LI, DT, TLI, TTI, AC, ORE, |
| 929 | EPI, LVL, CM, BFI, PSI, Check) {} |
| 930 | /// Implements the interface for creating a vectorized skeleton using the |
| 931 | /// *main loop* strategy (ie the first pass of vplan execution). |
| 932 | std::pair<BasicBlock *, Value *> |
| 933 | createEpilogueVectorizedLoopSkeleton() final override; |
| 934 | |
| 935 | protected: |
| 936 | /// Emits an iteration count bypass check once for the main loop (when \p |
| 937 | /// ForEpilogue is false) and once for the epilogue loop (when \p |
| 938 | /// ForEpilogue is true). |
| 939 | BasicBlock *emitMinimumIterationCountCheck(Loop *L, BasicBlock *Bypass, |
| 940 | bool ForEpilogue); |
| 941 | void printDebugTracesAtStart() override; |
| 942 | void printDebugTracesAtEnd() override; |
| 943 | }; |
| 944 | |
| 945 | // A specialized derived class of inner loop vectorizer that performs |
| 946 | // vectorization of *epilogue* loops in the process of vectorizing loops and |
| 947 | // their epilogues. |
| 948 | class EpilogueVectorizerEpilogueLoop : public InnerLoopAndEpilogueVectorizer { |
| 949 | public: |
| 950 | EpilogueVectorizerEpilogueLoop( |
| 951 | Loop *OrigLoop, PredicatedScalarEvolution &PSE, LoopInfo *LI, |
| 952 | DominatorTree *DT, const TargetLibraryInfo *TLI, |
| 953 | const TargetTransformInfo *TTI, AssumptionCache *AC, |
| 954 | OptimizationRemarkEmitter *ORE, EpilogueLoopVectorizationInfo &EPI, |
| 955 | LoopVectorizationLegality *LVL, llvm::LoopVectorizationCostModel *CM, |
| 956 | BlockFrequencyInfo *BFI, ProfileSummaryInfo *PSI, |
| 957 | GeneratedRTChecks &Checks) |
| 958 | : InnerLoopAndEpilogueVectorizer(OrigLoop, PSE, LI, DT, TLI, TTI, AC, ORE, |
| 959 | EPI, LVL, CM, BFI, PSI, Checks) {} |
| 960 | /// Implements the interface for creating a vectorized skeleton using the |
| 961 | /// *epilogue loop* strategy (ie the second pass of vplan execution). |
| 962 | std::pair<BasicBlock *, Value *> |
| 963 | createEpilogueVectorizedLoopSkeleton() final override; |
| 964 | |
| 965 | protected: |
| 966 | /// Emits an iteration count bypass check after the main vector loop has |
| 967 | /// finished to see if there are any iterations left to execute by either |
| 968 | /// the vector epilogue or the scalar epilogue. |
| 969 | BasicBlock *emitMinimumVectorEpilogueIterCountCheck(Loop *L, |
| 970 | BasicBlock *Bypass, |
| 971 | BasicBlock *Insert); |
| 972 | void printDebugTracesAtStart() override; |
| 973 | void printDebugTracesAtEnd() override; |
| 974 | }; |
| 975 | } // end namespace llvm |
| 976 | |
| 977 | /// Look for a meaningful debug location on the instruction or it's |
| 978 | /// operands. |
| 979 | static Instruction *getDebugLocFromInstOrOperands(Instruction *I) { |
| 980 | if (!I) |
| 981 | return I; |
| 982 | |
| 983 | DebugLoc Empty; |
| 984 | if (I->getDebugLoc() != Empty) |
| 985 | return I; |
| 986 | |
| 987 | for (Use &Op : I->operands()) { |
| 988 | if (Instruction *OpInst = dyn_cast<Instruction>(Op)) |
| 989 | if (OpInst->getDebugLoc() != Empty) |
| 990 | return OpInst; |
| 991 | } |
| 992 | |
| 993 | return I; |
| 994 | } |
| 995 | |
| 996 | void InnerLoopVectorizer::setDebugLocFromInst( |
| 997 | const Value *V, Optional<IRBuilder<> *> CustomBuilder) { |
| 998 | IRBuilder<> *B = (CustomBuilder == None) ? &Builder : *CustomBuilder; |
| 999 | if (const Instruction *Inst = dyn_cast_or_null<Instruction>(V)) { |
| 1000 | const DILocation *DIL = Inst->getDebugLoc(); |
| 1001 | |
| 1002 | // When a FSDiscriminator is enabled, we don't need to add the multiply |
| 1003 | // factors to the discriminators. |
| 1004 | if (DIL && Inst->getFunction()->isDebugInfoForProfiling() && |
| 1005 | !isa<DbgInfoIntrinsic>(Inst) && !EnableFSDiscriminator) { |
| 1006 | // FIXME: For scalable vectors, assume vscale=1. |
| 1007 | auto NewDIL = |
| 1008 | DIL->cloneByMultiplyingDuplicationFactor(UF * VF.getKnownMinValue()); |
| 1009 | if (NewDIL) |
| 1010 | B->SetCurrentDebugLocation(NewDIL.getValue()); |
| 1011 | else |
| 1012 | LLVM_DEBUG(dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "Failed to create new discriminator: " << DIL->getFilename() << " Line: " << DIL ->getLine(); } } while (false) |
| 1013 | << "Failed to create new discriminator: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "Failed to create new discriminator: " << DIL->getFilename() << " Line: " << DIL ->getLine(); } } while (false) |
| 1014 | << DIL->getFilename() << " Line: " << DIL->getLine())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "Failed to create new discriminator: " << DIL->getFilename() << " Line: " << DIL ->getLine(); } } while (false); |
| 1015 | } else |
| 1016 | B->SetCurrentDebugLocation(DIL); |
| 1017 | } else |
| 1018 | B->SetCurrentDebugLocation(DebugLoc()); |
| 1019 | } |
| 1020 | |
| 1021 | /// Write a \p DebugMsg about vectorization to the debug output stream. If \p I |
| 1022 | /// is passed, the message relates to that particular instruction. |
| 1023 | #ifndef NDEBUG |
| 1024 | static void debugVectorizationMessage(const StringRef Prefix, |
| 1025 | const StringRef DebugMsg, |
| 1026 | Instruction *I) { |
| 1027 | dbgs() << "LV: " << Prefix << DebugMsg; |
| 1028 | if (I != nullptr) |
| 1029 | dbgs() << " " << *I; |
| 1030 | else |
| 1031 | dbgs() << '.'; |
| 1032 | dbgs() << '\n'; |
| 1033 | } |
| 1034 | #endif |
| 1035 | |
| 1036 | /// Create an analysis remark that explains why vectorization failed |
| 1037 | /// |
| 1038 | /// \p PassName is the name of the pass (e.g. can be AlwaysPrint). \p |
| 1039 | /// RemarkName is the identifier for the remark. If \p I is passed it is an |
| 1040 | /// instruction that prevents vectorization. Otherwise \p TheLoop is used for |
| 1041 | /// the location of the remark. \return the remark object that can be |
| 1042 | /// streamed to. |
| 1043 | static OptimizationRemarkAnalysis createLVAnalysis(const char *PassName, |
| 1044 | StringRef RemarkName, Loop *TheLoop, Instruction *I) { |
| 1045 | Value *CodeRegion = TheLoop->getHeader(); |
| 1046 | DebugLoc DL = TheLoop->getStartLoc(); |
| 1047 | |
| 1048 | if (I) { |
| 1049 | CodeRegion = I->getParent(); |
| 1050 | // If there is no debug location attached to the instruction, revert back to |
| 1051 | // using the loop's. |
| 1052 | if (I->getDebugLoc()) |
| 1053 | DL = I->getDebugLoc(); |
| 1054 | } |
| 1055 | |
| 1056 | return OptimizationRemarkAnalysis(PassName, RemarkName, DL, CodeRegion); |
| 1057 | } |
| 1058 | |
| 1059 | namespace llvm { |
| 1060 | |
| 1061 | /// Return a value for Step multiplied by VF. |
| 1062 | Value *createStepForVF(IRBuilder<> &B, Type *Ty, ElementCount VF, |
| 1063 | int64_t Step) { |
| 1064 | assert(Ty->isIntegerTy() && "Expected an integer step")(static_cast <bool> (Ty->isIntegerTy() && "Expected an integer step" ) ? void (0) : __assert_fail ("Ty->isIntegerTy() && \"Expected an integer step\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1064, __extension__ __PRETTY_FUNCTION__)); |
| 1065 | Constant *StepVal = ConstantInt::get(Ty, Step * VF.getKnownMinValue()); |
| 1066 | return VF.isScalable() ? B.CreateVScale(StepVal) : StepVal; |
| 1067 | } |
| 1068 | |
| 1069 | /// Return the runtime value for VF. |
| 1070 | Value *getRuntimeVF(IRBuilder<> &B, Type *Ty, ElementCount VF) { |
| 1071 | Constant *EC = ConstantInt::get(Ty, VF.getKnownMinValue()); |
| 1072 | return VF.isScalable() ? B.CreateVScale(EC) : EC; |
| 1073 | } |
| 1074 | |
| 1075 | static Value *getRuntimeVFAsFloat(IRBuilder<> &B, Type *FTy, ElementCount VF) { |
| 1076 | assert(FTy->isFloatingPointTy() && "Expected floating point type!")(static_cast <bool> (FTy->isFloatingPointTy() && "Expected floating point type!") ? void (0) : __assert_fail ( "FTy->isFloatingPointTy() && \"Expected floating point type!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1076, __extension__ __PRETTY_FUNCTION__)); |
| 1077 | Type *IntTy = IntegerType::get(FTy->getContext(), FTy->getScalarSizeInBits()); |
| 1078 | Value *RuntimeVF = getRuntimeVF(B, IntTy, VF); |
| 1079 | return B.CreateUIToFP(RuntimeVF, FTy); |
| 1080 | } |
| 1081 | |
| 1082 | void reportVectorizationFailure(const StringRef DebugMsg, |
| 1083 | const StringRef OREMsg, const StringRef ORETag, |
| 1084 | OptimizationRemarkEmitter *ORE, Loop *TheLoop, |
| 1085 | Instruction *I) { |
| 1086 | LLVM_DEBUG(debugVectorizationMessage("Not vectorizing: ", DebugMsg, I))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { debugVectorizationMessage("Not vectorizing: " , DebugMsg, I); } } while (false); |
| 1087 | LoopVectorizeHints Hints(TheLoop, true /* doesn't matter */, *ORE); |
| 1088 | ORE->emit( |
| 1089 | createLVAnalysis(Hints.vectorizeAnalysisPassName(), ORETag, TheLoop, I) |
| 1090 | << "loop not vectorized: " << OREMsg); |
| 1091 | } |
| 1092 | |
| 1093 | void reportVectorizationInfo(const StringRef Msg, const StringRef ORETag, |
| 1094 | OptimizationRemarkEmitter *ORE, Loop *TheLoop, |
| 1095 | Instruction *I) { |
| 1096 | LLVM_DEBUG(debugVectorizationMessage("", Msg, I))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { debugVectorizationMessage("", Msg, I); } } while (false); |
| 1097 | LoopVectorizeHints Hints(TheLoop, true /* doesn't matter */, *ORE); |
| 1098 | ORE->emit( |
| 1099 | createLVAnalysis(Hints.vectorizeAnalysisPassName(), ORETag, TheLoop, I) |
| 1100 | << Msg); |
| 1101 | } |
| 1102 | |
| 1103 | } // end namespace llvm |
| 1104 | |
| 1105 | #ifndef NDEBUG |
| 1106 | /// \return string containing a file name and a line # for the given loop. |
| 1107 | static std::string getDebugLocString(const Loop *L) { |
| 1108 | std::string Result; |
| 1109 | if (L) { |
| 1110 | raw_string_ostream OS(Result); |
| 1111 | if (const DebugLoc LoopDbgLoc = L->getStartLoc()) |
| 1112 | LoopDbgLoc.print(OS); |
| 1113 | else |
| 1114 | // Just print the module name. |
| 1115 | OS << L->getHeader()->getParent()->getParent()->getModuleIdentifier(); |
| 1116 | OS.flush(); |
| 1117 | } |
| 1118 | return Result; |
| 1119 | } |
| 1120 | #endif |
| 1121 | |
| 1122 | void InnerLoopVectorizer::addNewMetadata(Instruction *To, |
| 1123 | const Instruction *Orig) { |
| 1124 | // If the loop was versioned with memchecks, add the corresponding no-alias |
| 1125 | // metadata. |
| 1126 | if (LVer && (isa<LoadInst>(Orig) || isa<StoreInst>(Orig))) |
| 1127 | LVer->annotateInstWithNoAlias(To, Orig); |
| 1128 | } |
| 1129 | |
| 1130 | void InnerLoopVectorizer::collectPoisonGeneratingRecipes( |
| 1131 | VPTransformState &State) { |
| 1132 | |
| 1133 | // Collect recipes in the backward slice of `Root` that may generate a poison |
| 1134 | // value that is used after vectorization. |
| 1135 | SmallPtrSet<VPRecipeBase *, 16> Visited; |
| 1136 | auto collectPoisonGeneratingInstrsInBackwardSlice([&](VPRecipeBase *Root) { |
| 1137 | SmallVector<VPRecipeBase *, 16> Worklist; |
| 1138 | Worklist.push_back(Root); |
| 1139 | |
| 1140 | // Traverse the backward slice of Root through its use-def chain. |
| 1141 | while (!Worklist.empty()) { |
| 1142 | VPRecipeBase *CurRec = Worklist.back(); |
| 1143 | Worklist.pop_back(); |
| 1144 | |
| 1145 | if (!Visited.insert(CurRec).second) |
| 1146 | continue; |
| 1147 | |
| 1148 | // Prune search if we find another recipe generating a widen memory |
| 1149 | // instruction. Widen memory instructions involved in address computation |
| 1150 | // will lead to gather/scatter instructions, which don't need to be |
| 1151 | // handled. |
| 1152 | if (isa<VPWidenMemoryInstructionRecipe>(CurRec) || |
| 1153 | isa<VPInterleaveRecipe>(CurRec) || |
| 1154 | isa<VPCanonicalIVPHIRecipe>(CurRec)) |
| 1155 | continue; |
| 1156 | |
| 1157 | // This recipe contributes to the address computation of a widen |
| 1158 | // load/store. Collect recipe if its underlying instruction has |
| 1159 | // poison-generating flags. |
| 1160 | Instruction *Instr = CurRec->getUnderlyingInstr(); |
| 1161 | if (Instr && Instr->hasPoisonGeneratingFlags()) |
| 1162 | State.MayGeneratePoisonRecipes.insert(CurRec); |
| 1163 | |
| 1164 | // Add new definitions to the worklist. |
| 1165 | for (VPValue *operand : CurRec->operands()) |
| 1166 | if (VPDef *OpDef = operand->getDef()) |
| 1167 | Worklist.push_back(cast<VPRecipeBase>(OpDef)); |
| 1168 | } |
| 1169 | }); |
| 1170 | |
| 1171 | // Traverse all the recipes in the VPlan and collect the poison-generating |
| 1172 | // recipes in the backward slice starting at the address of a VPWidenRecipe or |
| 1173 | // VPInterleaveRecipe. |
| 1174 | auto Iter = depth_first( |
| 1175 | VPBlockRecursiveTraversalWrapper<VPBlockBase *>(State.Plan->getEntry())); |
| 1176 | for (VPBasicBlock *VPBB : VPBlockUtils::blocksOnly<VPBasicBlock>(Iter)) { |
| 1177 | for (VPRecipeBase &Recipe : *VPBB) { |
| 1178 | if (auto *WidenRec = dyn_cast<VPWidenMemoryInstructionRecipe>(&Recipe)) { |
| 1179 | Instruction *UnderlyingInstr = WidenRec->getUnderlyingInstr(); |
| 1180 | VPDef *AddrDef = WidenRec->getAddr()->getDef(); |
| 1181 | if (AddrDef && WidenRec->isConsecutive() && UnderlyingInstr && |
| 1182 | Legal->blockNeedsPredication(UnderlyingInstr->getParent())) |
| 1183 | collectPoisonGeneratingInstrsInBackwardSlice( |
| 1184 | cast<VPRecipeBase>(AddrDef)); |
| 1185 | } else if (auto *InterleaveRec = dyn_cast<VPInterleaveRecipe>(&Recipe)) { |
| 1186 | VPDef *AddrDef = InterleaveRec->getAddr()->getDef(); |
| 1187 | if (AddrDef) { |
| 1188 | // Check if any member of the interleave group needs predication. |
| 1189 | const InterleaveGroup<Instruction> *InterGroup = |
| 1190 | InterleaveRec->getInterleaveGroup(); |
| 1191 | bool NeedPredication = false; |
| 1192 | for (int I = 0, NumMembers = InterGroup->getNumMembers(); |
| 1193 | I < NumMembers; ++I) { |
| 1194 | Instruction *Member = InterGroup->getMember(I); |
| 1195 | if (Member) |
| 1196 | NeedPredication |= |
| 1197 | Legal->blockNeedsPredication(Member->getParent()); |
| 1198 | } |
| 1199 | |
| 1200 | if (NeedPredication) |
| 1201 | collectPoisonGeneratingInstrsInBackwardSlice( |
| 1202 | cast<VPRecipeBase>(AddrDef)); |
| 1203 | } |
| 1204 | } |
| 1205 | } |
| 1206 | } |
| 1207 | } |
| 1208 | |
| 1209 | void InnerLoopVectorizer::addMetadata(Instruction *To, |
| 1210 | Instruction *From) { |
| 1211 | propagateMetadata(To, From); |
| 1212 | addNewMetadata(To, From); |
| 1213 | } |
| 1214 | |
| 1215 | void InnerLoopVectorizer::addMetadata(ArrayRef<Value *> To, |
| 1216 | Instruction *From) { |
| 1217 | for (Value *V : To) { |
| 1218 | if (Instruction *I = dyn_cast<Instruction>(V)) |
| 1219 | addMetadata(I, From); |
| 1220 | } |
| 1221 | } |
| 1222 | |
| 1223 | PHINode *InnerLoopVectorizer::getReductionResumeValue( |
| 1224 | const RecurrenceDescriptor &RdxDesc) { |
| 1225 | auto It = ReductionResumeValues.find(&RdxDesc); |
| 1226 | assert(It != ReductionResumeValues.end() &&(static_cast <bool> (It != ReductionResumeValues.end() && "Expected to find a resume value for the reduction.") ? void (0) : __assert_fail ("It != ReductionResumeValues.end() && \"Expected to find a resume value for the reduction.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1227, __extension__ __PRETTY_FUNCTION__)) |
| 1227 | "Expected to find a resume value for the reduction.")(static_cast <bool> (It != ReductionResumeValues.end() && "Expected to find a resume value for the reduction.") ? void (0) : __assert_fail ("It != ReductionResumeValues.end() && \"Expected to find a resume value for the reduction.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1227, __extension__ __PRETTY_FUNCTION__)); |
| 1228 | return It->second; |
| 1229 | } |
| 1230 | |
| 1231 | namespace llvm { |
| 1232 | |
| 1233 | // Loop vectorization cost-model hints how the scalar epilogue loop should be |
| 1234 | // lowered. |
| 1235 | enum ScalarEpilogueLowering { |
| 1236 | |
| 1237 | // The default: allowing scalar epilogues. |
| 1238 | CM_ScalarEpilogueAllowed, |
| 1239 | |
| 1240 | // Vectorization with OptForSize: don't allow epilogues. |
| 1241 | CM_ScalarEpilogueNotAllowedOptSize, |
| 1242 | |
| 1243 | // A special case of vectorisation with OptForSize: loops with a very small |
| 1244 | // trip count are considered for vectorization under OptForSize, thereby |
| 1245 | // making sure the cost of their loop body is dominant, free of runtime |
| 1246 | // guards and scalar iteration overheads. |
| 1247 | CM_ScalarEpilogueNotAllowedLowTripLoop, |
| 1248 | |
| 1249 | // Loop hint predicate indicating an epilogue is undesired. |
| 1250 | CM_ScalarEpilogueNotNeededUsePredicate, |
| 1251 | |
| 1252 | // Directive indicating we must either tail fold or not vectorize |
| 1253 | CM_ScalarEpilogueNotAllowedUsePredicate |
| 1254 | }; |
| 1255 | |
| 1256 | /// ElementCountComparator creates a total ordering for ElementCount |
| 1257 | /// for the purposes of using it in a set structure. |
| 1258 | struct ElementCountComparator { |
| 1259 | bool operator()(const ElementCount &LHS, const ElementCount &RHS) const { |
| 1260 | return std::make_tuple(LHS.isScalable(), LHS.getKnownMinValue()) < |
| 1261 | std::make_tuple(RHS.isScalable(), RHS.getKnownMinValue()); |
| 1262 | } |
| 1263 | }; |
| 1264 | using ElementCountSet = SmallSet<ElementCount, 16, ElementCountComparator>; |
| 1265 | |
| 1266 | /// LoopVectorizationCostModel - estimates the expected speedups due to |
| 1267 | /// vectorization. |
| 1268 | /// In many cases vectorization is not profitable. This can happen because of |
| 1269 | /// a number of reasons. In this class we mainly attempt to predict the |
| 1270 | /// expected speedup/slowdowns due to the supported instruction set. We use the |
| 1271 | /// TargetTransformInfo to query the different backends for the cost of |
| 1272 | /// different operations. |
| 1273 | class LoopVectorizationCostModel { |
| 1274 | public: |
| 1275 | LoopVectorizationCostModel(ScalarEpilogueLowering SEL, Loop *L, |
| 1276 | PredicatedScalarEvolution &PSE, LoopInfo *LI, |
| 1277 | LoopVectorizationLegality *Legal, |
| 1278 | const TargetTransformInfo &TTI, |
| 1279 | const TargetLibraryInfo *TLI, DemandedBits *DB, |
| 1280 | AssumptionCache *AC, |
| 1281 | OptimizationRemarkEmitter *ORE, const Function *F, |
| 1282 | const LoopVectorizeHints *Hints, |
| 1283 | InterleavedAccessInfo &IAI) |
| 1284 | : ScalarEpilogueStatus(SEL), TheLoop(L), PSE(PSE), LI(LI), Legal(Legal), |
| 1285 | TTI(TTI), TLI(TLI), DB(DB), AC(AC), ORE(ORE), TheFunction(F), |
| 1286 | Hints(Hints), InterleaveInfo(IAI) {} |
| 1287 | |
| 1288 | /// \return An upper bound for the vectorization factors (both fixed and |
| 1289 | /// scalable). If the factors are 0, vectorization and interleaving should be |
| 1290 | /// avoided up front. |
| 1291 | FixedScalableVFPair computeMaxVF(ElementCount UserVF, unsigned UserIC); |
| 1292 | |
| 1293 | /// \return True if runtime checks are required for vectorization, and false |
| 1294 | /// otherwise. |
| 1295 | bool runtimeChecksRequired(); |
| 1296 | |
| 1297 | /// \return The most profitable vectorization factor and the cost of that VF. |
| 1298 | /// This method checks every VF in \p CandidateVFs. If UserVF is not ZERO |
| 1299 | /// then this vectorization factor will be selected if vectorization is |
| 1300 | /// possible. |
| 1301 | VectorizationFactor |
| 1302 | selectVectorizationFactor(const ElementCountSet &CandidateVFs); |
| 1303 | |
| 1304 | VectorizationFactor |
| 1305 | selectEpilogueVectorizationFactor(const ElementCount MaxVF, |
| 1306 | const LoopVectorizationPlanner &LVP); |
| 1307 | |
| 1308 | /// Setup cost-based decisions for user vectorization factor. |
| 1309 | /// \return true if the UserVF is a feasible VF to be chosen. |
| 1310 | bool selectUserVectorizationFactor(ElementCount UserVF) { |
| 1311 | collectUniformsAndScalars(UserVF); |
| 1312 | collectInstsToScalarize(UserVF); |
| 1313 | return expectedCost(UserVF).first.isValid(); |
| 1314 | } |
| 1315 | |
| 1316 | /// \return The size (in bits) of the smallest and widest types in the code |
| 1317 | /// that needs to be vectorized. We ignore values that remain scalar such as |
| 1318 | /// 64 bit loop indices. |
| 1319 | std::pair<unsigned, unsigned> getSmallestAndWidestTypes(); |
| 1320 | |
| 1321 | /// \return The desired interleave count. |
| 1322 | /// If interleave count has been specified by metadata it will be returned. |
| 1323 | /// Otherwise, the interleave count is computed and returned. VF and LoopCost |
| 1324 | /// are the selected vectorization factor and the cost of the selected VF. |
| 1325 | unsigned selectInterleaveCount(ElementCount VF, unsigned LoopCost); |
| 1326 | |
| 1327 | /// Memory access instruction may be vectorized in more than one way. |
| 1328 | /// Form of instruction after vectorization depends on cost. |
| 1329 | /// This function takes cost-based decisions for Load/Store instructions |
| 1330 | /// and collects them in a map. This decisions map is used for building |
| 1331 | /// the lists of loop-uniform and loop-scalar instructions. |
| 1332 | /// The calculated cost is saved with widening decision in order to |
| 1333 | /// avoid redundant calculations. |
| 1334 | void setCostBasedWideningDecision(ElementCount VF); |
| 1335 | |
| 1336 | /// A struct that represents some properties of the register usage |
| 1337 | /// of a loop. |
| 1338 | struct RegisterUsage { |
| 1339 | /// Holds the number of loop invariant values that are used in the loop. |
| 1340 | /// The key is ClassID of target-provided register class. |
| 1341 | SmallMapVector<unsigned, unsigned, 4> LoopInvariantRegs; |
| 1342 | /// Holds the maximum number of concurrent live intervals in the loop. |
| 1343 | /// The key is ClassID of target-provided register class. |
| 1344 | SmallMapVector<unsigned, unsigned, 4> MaxLocalUsers; |
| 1345 | }; |
| 1346 | |
| 1347 | /// \return Returns information about the register usages of the loop for the |
| 1348 | /// given vectorization factors. |
| 1349 | SmallVector<RegisterUsage, 8> |
| 1350 | calculateRegisterUsage(ArrayRef<ElementCount> VFs); |
| 1351 | |
| 1352 | /// Collect values we want to ignore in the cost model. |
| 1353 | void collectValuesToIgnore(); |
| 1354 | |
| 1355 | /// Collect all element types in the loop for which widening is needed. |
| 1356 | void collectElementTypesForWidening(); |
| 1357 | |
| 1358 | /// Split reductions into those that happen in the loop, and those that happen |
| 1359 | /// outside. In loop reductions are collected into InLoopReductionChains. |
| 1360 | void collectInLoopReductions(); |
| 1361 | |
| 1362 | /// Returns true if we should use strict in-order reductions for the given |
| 1363 | /// RdxDesc. This is true if the -enable-strict-reductions flag is passed, |
| 1364 | /// the IsOrdered flag of RdxDesc is set and we do not allow reordering |
| 1365 | /// of FP operations. |
| 1366 | bool useOrderedReductions(const RecurrenceDescriptor &RdxDesc) { |
| 1367 | return !Hints->allowReordering() && RdxDesc.isOrdered(); |
| 1368 | } |
| 1369 | |
| 1370 | /// \returns The smallest bitwidth each instruction can be represented with. |
| 1371 | /// The vector equivalents of these instructions should be truncated to this |
| 1372 | /// type. |
| 1373 | const MapVector<Instruction *, uint64_t> &getMinimalBitwidths() const { |
| 1374 | return MinBWs; |
| 1375 | } |
| 1376 | |
| 1377 | /// \returns True if it is more profitable to scalarize instruction \p I for |
| 1378 | /// vectorization factor \p VF. |
| 1379 | bool isProfitableToScalarize(Instruction *I, ElementCount VF) const { |
| 1380 | assert(VF.isVector() &&(static_cast <bool> (VF.isVector() && "Profitable to scalarize relevant only for VF > 1." ) ? void (0) : __assert_fail ("VF.isVector() && \"Profitable to scalarize relevant only for VF > 1.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1381, __extension__ __PRETTY_FUNCTION__)) |
| 1381 | "Profitable to scalarize relevant only for VF > 1.")(static_cast <bool> (VF.isVector() && "Profitable to scalarize relevant only for VF > 1." ) ? void (0) : __assert_fail ("VF.isVector() && \"Profitable to scalarize relevant only for VF > 1.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1381, __extension__ __PRETTY_FUNCTION__)); |
| 1382 | |
| 1383 | // Cost model is not run in the VPlan-native path - return conservative |
| 1384 | // result until this changes. |
| 1385 | if (EnableVPlanNativePath) |
| 1386 | return false; |
| 1387 | |
| 1388 | auto Scalars = InstsToScalarize.find(VF); |
| 1389 | assert(Scalars != InstsToScalarize.end() &&(static_cast <bool> (Scalars != InstsToScalarize.end() && "VF not yet analyzed for scalarization profitability") ? void (0) : __assert_fail ("Scalars != InstsToScalarize.end() && \"VF not yet analyzed for scalarization profitability\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1390, __extension__ __PRETTY_FUNCTION__)) |
| 1390 | "VF not yet analyzed for scalarization profitability")(static_cast <bool> (Scalars != InstsToScalarize.end() && "VF not yet analyzed for scalarization profitability") ? void (0) : __assert_fail ("Scalars != InstsToScalarize.end() && \"VF not yet analyzed for scalarization profitability\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1390, __extension__ __PRETTY_FUNCTION__)); |
| 1391 | return Scalars->second.find(I) != Scalars->second.end(); |
| 1392 | } |
| 1393 | |
| 1394 | /// Returns true if \p I is known to be uniform after vectorization. |
| 1395 | bool isUniformAfterVectorization(Instruction *I, ElementCount VF) const { |
| 1396 | if (VF.isScalar()) |
| 1397 | return true; |
| 1398 | |
| 1399 | // Cost model is not run in the VPlan-native path - return conservative |
| 1400 | // result until this changes. |
| 1401 | if (EnableVPlanNativePath) |
| 1402 | return false; |
| 1403 | |
| 1404 | auto UniformsPerVF = Uniforms.find(VF); |
| 1405 | assert(UniformsPerVF != Uniforms.end() &&(static_cast <bool> (UniformsPerVF != Uniforms.end() && "VF not yet analyzed for uniformity") ? void (0) : __assert_fail ("UniformsPerVF != Uniforms.end() && \"VF not yet analyzed for uniformity\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1406, __extension__ __PRETTY_FUNCTION__)) |
| 1406 | "VF not yet analyzed for uniformity")(static_cast <bool> (UniformsPerVF != Uniforms.end() && "VF not yet analyzed for uniformity") ? void (0) : __assert_fail ("UniformsPerVF != Uniforms.end() && \"VF not yet analyzed for uniformity\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1406, __extension__ __PRETTY_FUNCTION__)); |
| 1407 | return UniformsPerVF->second.count(I); |
| 1408 | } |
| 1409 | |
| 1410 | /// Returns true if \p I is known to be scalar after vectorization. |
| 1411 | bool isScalarAfterVectorization(Instruction *I, ElementCount VF) const { |
| 1412 | if (VF.isScalar()) |
| 1413 | return true; |
| 1414 | |
| 1415 | // Cost model is not run in the VPlan-native path - return conservative |
| 1416 | // result until this changes. |
| 1417 | if (EnableVPlanNativePath) |
| 1418 | return false; |
| 1419 | |
| 1420 | auto ScalarsPerVF = Scalars.find(VF); |
| 1421 | assert(ScalarsPerVF != Scalars.end() &&(static_cast <bool> (ScalarsPerVF != Scalars.end() && "Scalar values are not calculated for VF") ? void (0) : __assert_fail ("ScalarsPerVF != Scalars.end() && \"Scalar values are not calculated for VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1422, __extension__ __PRETTY_FUNCTION__)) |
| 1422 | "Scalar values are not calculated for VF")(static_cast <bool> (ScalarsPerVF != Scalars.end() && "Scalar values are not calculated for VF") ? void (0) : __assert_fail ("ScalarsPerVF != Scalars.end() && \"Scalar values are not calculated for VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1422, __extension__ __PRETTY_FUNCTION__)); |
| 1423 | return ScalarsPerVF->second.count(I); |
| 1424 | } |
| 1425 | |
| 1426 | /// \returns True if instruction \p I can be truncated to a smaller bitwidth |
| 1427 | /// for vectorization factor \p VF. |
| 1428 | bool canTruncateToMinimalBitwidth(Instruction *I, ElementCount VF) const { |
| 1429 | return VF.isVector() && MinBWs.find(I) != MinBWs.end() && |
| 1430 | !isProfitableToScalarize(I, VF) && |
| 1431 | !isScalarAfterVectorization(I, VF); |
| 1432 | } |
| 1433 | |
| 1434 | /// Decision that was taken during cost calculation for memory instruction. |
| 1435 | enum InstWidening { |
| 1436 | CM_Unknown, |
| 1437 | CM_Widen, // For consecutive accesses with stride +1. |
| 1438 | CM_Widen_Reverse, // For consecutive accesses with stride -1. |
| 1439 | CM_Interleave, |
| 1440 | CM_GatherScatter, |
| 1441 | CM_Scalarize |
| 1442 | }; |
| 1443 | |
| 1444 | /// Save vectorization decision \p W and \p Cost taken by the cost model for |
| 1445 | /// instruction \p I and vector width \p VF. |
| 1446 | void setWideningDecision(Instruction *I, ElementCount VF, InstWidening W, |
| 1447 | InstructionCost Cost) { |
| 1448 | assert(VF.isVector() && "Expected VF >=2")(static_cast <bool> (VF.isVector() && "Expected VF >=2" ) ? void (0) : __assert_fail ("VF.isVector() && \"Expected VF >=2\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1448, __extension__ __PRETTY_FUNCTION__)); |
| 1449 | WideningDecisions[std::make_pair(I, VF)] = std::make_pair(W, Cost); |
| 1450 | } |
| 1451 | |
| 1452 | /// Save vectorization decision \p W and \p Cost taken by the cost model for |
| 1453 | /// interleaving group \p Grp and vector width \p VF. |
| 1454 | void setWideningDecision(const InterleaveGroup<Instruction> *Grp, |
| 1455 | ElementCount VF, InstWidening W, |
| 1456 | InstructionCost Cost) { |
| 1457 | assert(VF.isVector() && "Expected VF >=2")(static_cast <bool> (VF.isVector() && "Expected VF >=2" ) ? void (0) : __assert_fail ("VF.isVector() && \"Expected VF >=2\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1457, __extension__ __PRETTY_FUNCTION__)); |
| 1458 | /// Broadcast this decicion to all instructions inside the group. |
| 1459 | /// But the cost will be assigned to one instruction only. |
| 1460 | for (unsigned i = 0; i < Grp->getFactor(); ++i) { |
| 1461 | if (auto *I = Grp->getMember(i)) { |
| 1462 | if (Grp->getInsertPos() == I) |
| 1463 | WideningDecisions[std::make_pair(I, VF)] = std::make_pair(W, Cost); |
| 1464 | else |
| 1465 | WideningDecisions[std::make_pair(I, VF)] = std::make_pair(W, 0); |
| 1466 | } |
| 1467 | } |
| 1468 | } |
| 1469 | |
| 1470 | /// Return the cost model decision for the given instruction \p I and vector |
| 1471 | /// width \p VF. Return CM_Unknown if this instruction did not pass |
| 1472 | /// through the cost modeling. |
| 1473 | InstWidening getWideningDecision(Instruction *I, ElementCount VF) const { |
| 1474 | assert(VF.isVector() && "Expected VF to be a vector VF")(static_cast <bool> (VF.isVector() && "Expected VF to be a vector VF" ) ? void (0) : __assert_fail ("VF.isVector() && \"Expected VF to be a vector VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1474, __extension__ __PRETTY_FUNCTION__)); |
| 1475 | // Cost model is not run in the VPlan-native path - return conservative |
| 1476 | // result until this changes. |
| 1477 | if (EnableVPlanNativePath) |
| 1478 | return CM_GatherScatter; |
| 1479 | |
| 1480 | std::pair<Instruction *, ElementCount> InstOnVF = std::make_pair(I, VF); |
| 1481 | auto Itr = WideningDecisions.find(InstOnVF); |
| 1482 | if (Itr == WideningDecisions.end()) |
| 1483 | return CM_Unknown; |
| 1484 | return Itr->second.first; |
| 1485 | } |
| 1486 | |
| 1487 | /// Return the vectorization cost for the given instruction \p I and vector |
| 1488 | /// width \p VF. |
| 1489 | InstructionCost getWideningCost(Instruction *I, ElementCount VF) { |
| 1490 | assert(VF.isVector() && "Expected VF >=2")(static_cast <bool> (VF.isVector() && "Expected VF >=2" ) ? void (0) : __assert_fail ("VF.isVector() && \"Expected VF >=2\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1490, __extension__ __PRETTY_FUNCTION__)); |
| 1491 | std::pair<Instruction *, ElementCount> InstOnVF = std::make_pair(I, VF); |
| 1492 | assert(WideningDecisions.find(InstOnVF) != WideningDecisions.end() &&(static_cast <bool> (WideningDecisions.find(InstOnVF) != WideningDecisions.end() && "The cost is not calculated" ) ? void (0) : __assert_fail ("WideningDecisions.find(InstOnVF) != WideningDecisions.end() && \"The cost is not calculated\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1493, __extension__ __PRETTY_FUNCTION__)) |
| 1493 | "The cost is not calculated")(static_cast <bool> (WideningDecisions.find(InstOnVF) != WideningDecisions.end() && "The cost is not calculated" ) ? void (0) : __assert_fail ("WideningDecisions.find(InstOnVF) != WideningDecisions.end() && \"The cost is not calculated\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 1493, __extension__ __PRETTY_FUNCTION__)); |
| 1494 | return WideningDecisions[InstOnVF].second; |
| 1495 | } |
| 1496 | |
| 1497 | /// Return True if instruction \p I is an optimizable truncate whose operand |
| 1498 | /// is an induction variable. Such a truncate will be removed by adding a new |
| 1499 | /// induction variable with the destination type. |
| 1500 | bool isOptimizableIVTruncate(Instruction *I, ElementCount VF) { |
| 1501 | // If the instruction is not a truncate, return false. |
| 1502 | auto *Trunc = dyn_cast<TruncInst>(I); |
| 1503 | if (!Trunc) |
| 1504 | return false; |
| 1505 | |
| 1506 | // Get the source and destination types of the truncate. |
| 1507 | Type *SrcTy = ToVectorTy(cast<CastInst>(I)->getSrcTy(), VF); |
| 1508 | Type *DestTy = ToVectorTy(cast<CastInst>(I)->getDestTy(), VF); |
| 1509 | |
| 1510 | // If the truncate is free for the given types, return false. Replacing a |
| 1511 | // free truncate with an induction variable would add an induction variable |
| 1512 | // update instruction to each iteration of the loop. We exclude from this |
| 1513 | // check the primary induction variable since it will need an update |
| 1514 | // instruction regardless. |
| 1515 | Value *Op = Trunc->getOperand(0); |
| 1516 | if (Op != Legal->getPrimaryInduction() && TTI.isTruncateFree(SrcTy, DestTy)) |
| 1517 | return false; |
| 1518 | |
| 1519 | // If the truncated value is not an induction variable, return false. |
| 1520 | return Legal->isInductionPhi(Op); |
| 1521 | } |
| 1522 | |
| 1523 | /// Collects the instructions to scalarize for each predicated instruction in |
| 1524 | /// the loop. |
| 1525 | void collectInstsToScalarize(ElementCount VF); |
| 1526 | |
| 1527 | /// Collect Uniform and Scalar values for the given \p VF. |
| 1528 | /// The sets depend on CM decision for Load/Store instructions |
| 1529 | /// that may be vectorized as interleave, gather-scatter or scalarized. |
| 1530 | void collectUniformsAndScalars(ElementCount VF) { |
| 1531 | // Do the analysis once. |
| 1532 | if (VF.isScalar() || Uniforms.find(VF) != Uniforms.end()) |
| 1533 | return; |
| 1534 | setCostBasedWideningDecision(VF); |
| 1535 | collectLoopUniforms(VF); |
| 1536 | collectLoopScalars(VF); |
| 1537 | } |
| 1538 | |
| 1539 | /// Returns true if the target machine supports masked store operation |
| 1540 | /// for the given \p DataType and kind of access to \p Ptr. |
| 1541 | bool isLegalMaskedStore(Type *DataType, Value *Ptr, Align Alignment) const { |
| 1542 | return Legal->isConsecutivePtr(DataType, Ptr) && |
| 1543 | TTI.isLegalMaskedStore(DataType, Alignment); |
| 1544 | } |
| 1545 | |
| 1546 | /// Returns true if the target machine supports masked load operation |
| 1547 | /// for the given \p DataType and kind of access to \p Ptr. |
| 1548 | bool isLegalMaskedLoad(Type *DataType, Value *Ptr, Align Alignment) const { |
| 1549 | return Legal->isConsecutivePtr(DataType, Ptr) && |
| 1550 | TTI.isLegalMaskedLoad(DataType, Alignment); |
| 1551 | } |
| 1552 | |
| 1553 | /// Returns true if the target machine can represent \p V as a masked gather |
| 1554 | /// or scatter operation. |
| 1555 | bool isLegalGatherOrScatter(Value *V, |
| 1556 | ElementCount VF = ElementCount::getFixed(1)) { |
| 1557 | bool LI = isa<LoadInst>(V); |
| 1558 | bool SI = isa<StoreInst>(V); |
| 1559 | if (!LI && !SI) |
| 1560 | return false; |
| 1561 | auto *Ty = getLoadStoreType(V); |
| 1562 | Align Align = getLoadStoreAlignment(V); |
| 1563 | if (VF.isVector()) |
| 1564 | Ty = VectorType::get(Ty, VF); |
| 1565 | return (LI && TTI.isLegalMaskedGather(Ty, Align)) || |
| 1566 | (SI && TTI.isLegalMaskedScatter(Ty, Align)); |
| 1567 | } |
| 1568 | |
| 1569 | /// Returns true if the target machine supports all of the reduction |
| 1570 | /// variables found for the given VF. |
| 1571 | bool canVectorizeReductions(ElementCount VF) const { |
| 1572 | return (all_of(Legal->getReductionVars(), [&](auto &Reduction) -> bool { |
| 1573 | const RecurrenceDescriptor &RdxDesc = Reduction.second; |
| 1574 | return TTI.isLegalToVectorizeReduction(RdxDesc, VF); |
| 1575 | })); |
| 1576 | } |
| 1577 | |
| 1578 | /// Returns true if \p I is an instruction that will be scalarized with |
| 1579 | /// predication when vectorizing \p I with vectorization factor \p VF. Such |
| 1580 | /// instructions include conditional stores and instructions that may divide |
| 1581 | /// by zero. |
| 1582 | bool isScalarWithPredication(Instruction *I, ElementCount VF) const; |
| 1583 | |
| 1584 | // Returns true if \p I is an instruction that will be predicated either |
| 1585 | // through scalar predication or masked load/store or masked gather/scatter. |
| 1586 | // \p VF is the vectorization factor that will be used to vectorize \p I. |
| 1587 | // Superset of instructions that return true for isScalarWithPredication. |
| 1588 | bool isPredicatedInst(Instruction *I, ElementCount VF, |
| 1589 | bool IsKnownUniform = false) { |
| 1590 | // When we know the load is uniform and the original scalar loop was not |
| 1591 | // predicated we don't need to mark it as a predicated instruction. Any |
| 1592 | // vectorised blocks created when tail-folding are something artificial we |
| 1593 | // have introduced and we know there is always at least one active lane. |
| 1594 | // That's why we call Legal->blockNeedsPredication here because it doesn't |
| 1595 | // query tail-folding. |
| 1596 | if (IsKnownUniform && isa<LoadInst>(I) && |
| 1597 | !Legal->blockNeedsPredication(I->getParent())) |
| 1598 | return false; |
| 1599 | if (!blockNeedsPredicationForAnyReason(I->getParent())) |
| 1600 | return false; |
| 1601 | // Loads and stores that need some form of masked operation are predicated |
| 1602 | // instructions. |
| 1603 | if (isa<LoadInst>(I) || isa<StoreInst>(I)) |
| 1604 | return Legal->isMaskRequired(I); |
| 1605 | return isScalarWithPredication(I, VF); |
| 1606 | } |
| 1607 | |
| 1608 | /// Returns true if \p I is a memory instruction with consecutive memory |
| 1609 | /// access that can be widened. |
| 1610 | bool |
| 1611 | memoryInstructionCanBeWidened(Instruction *I, |
| 1612 | ElementCount VF = ElementCount::getFixed(1)); |
| 1613 | |
| 1614 | /// Returns true if \p I is a memory instruction in an interleaved-group |
| 1615 | /// of memory accesses that can be vectorized with wide vector loads/stores |
| 1616 | /// and shuffles. |
| 1617 | bool |
| 1618 | interleavedAccessCanBeWidened(Instruction *I, |
| 1619 | ElementCount VF = ElementCount::getFixed(1)); |
| 1620 | |
| 1621 | /// Check if \p Instr belongs to any interleaved access group. |
| 1622 | bool isAccessInterleaved(Instruction *Instr) { |
| 1623 | return InterleaveInfo.isInterleaved(Instr); |
| 1624 | } |
| 1625 | |
| 1626 | /// Get the interleaved access group that \p Instr belongs to. |
| 1627 | const InterleaveGroup<Instruction> * |
| 1628 | getInterleavedAccessGroup(Instruction *Instr) { |
| 1629 | return InterleaveInfo.getInterleaveGroup(Instr); |
| 1630 | } |
| 1631 | |
| 1632 | /// Returns true if we're required to use a scalar epilogue for at least |
| 1633 | /// the final iteration of the original loop. |
| 1634 | bool requiresScalarEpilogue(ElementCount VF) const { |
| 1635 | if (!isScalarEpilogueAllowed()) |
| 1636 | return false; |
| 1637 | // If we might exit from anywhere but the latch, must run the exiting |
| 1638 | // iteration in scalar form. |
| 1639 | if (TheLoop->getExitingBlock() != TheLoop->getLoopLatch()) |
| 1640 | return true; |
| 1641 | return VF.isVector() && InterleaveInfo.requiresScalarEpilogue(); |
| 1642 | } |
| 1643 | |
| 1644 | /// Returns true if a scalar epilogue is not allowed due to optsize or a |
| 1645 | /// loop hint annotation. |
| 1646 | bool isScalarEpilogueAllowed() const { |
| 1647 | return ScalarEpilogueStatus == CM_ScalarEpilogueAllowed; |
| 1648 | } |
| 1649 | |
| 1650 | /// Returns true if all loop blocks should be masked to fold tail loop. |
| 1651 | bool foldTailByMasking() const { return FoldTailByMasking; } |
| 1652 | |
| 1653 | /// Returns true if the instructions in this block requires predication |
| 1654 | /// for any reason, e.g. because tail folding now requires a predicate |
| 1655 | /// or because the block in the original loop was predicated. |
| 1656 | bool blockNeedsPredicationForAnyReason(BasicBlock *BB) const { |
| 1657 | return foldTailByMasking() || Legal->blockNeedsPredication(BB); |
| 1658 | } |
| 1659 | |
| 1660 | /// A SmallMapVector to store the InLoop reduction op chains, mapping phi |
| 1661 | /// nodes to the chain of instructions representing the reductions. Uses a |
| 1662 | /// MapVector to ensure deterministic iteration order. |
| 1663 | using ReductionChainMap = |
| 1664 | SmallMapVector<PHINode *, SmallVector<Instruction *, 4>, 4>; |
| 1665 | |
| 1666 | /// Return the chain of instructions representing an inloop reduction. |
| 1667 | const ReductionChainMap &getInLoopReductionChains() const { |
| 1668 | return InLoopReductionChains; |
| 1669 | } |
| 1670 | |
| 1671 | /// Returns true if the Phi is part of an inloop reduction. |
| 1672 | bool isInLoopReduction(PHINode *Phi) const { |
| 1673 | return InLoopReductionChains.count(Phi); |
| 1674 | } |
| 1675 | |
| 1676 | /// Estimate cost of an intrinsic call instruction CI if it were vectorized |
| 1677 | /// with factor VF. Return the cost of the instruction, including |
| 1678 | /// scalarization overhead if it's needed. |
| 1679 | InstructionCost getVectorIntrinsicCost(CallInst *CI, ElementCount VF) const; |
| 1680 | |
| 1681 | /// Estimate cost of a call instruction CI if it were vectorized with factor |
| 1682 | /// VF. Return the cost of the instruction, including scalarization overhead |
| 1683 | /// if it's needed. The flag NeedToScalarize shows if the call needs to be |
| 1684 | /// scalarized - |
| 1685 | /// i.e. either vector version isn't available, or is too expensive. |
| 1686 | InstructionCost getVectorCallCost(CallInst *CI, ElementCount VF, |
| 1687 | bool &NeedToScalarize) const; |
| 1688 | |
| 1689 | /// Returns true if the per-lane cost of VectorizationFactor A is lower than |
| 1690 | /// that of B. |
| 1691 | bool isMoreProfitable(const VectorizationFactor &A, |
| 1692 | const VectorizationFactor &B) const; |
| 1693 | |
| 1694 | /// Invalidates decisions already taken by the cost model. |
| 1695 | void invalidateCostModelingDecisions() { |
| 1696 | WideningDecisions.clear(); |
| 1697 | Uniforms.clear(); |
| 1698 | Scalars.clear(); |
| 1699 | } |
| 1700 | |
| 1701 | private: |
| 1702 | unsigned NumPredStores = 0; |
| 1703 | |
| 1704 | /// Convenience function that returns the value of vscale_range iff |
| 1705 | /// vscale_range.min == vscale_range.max or otherwise returns the value |
| 1706 | /// returned by the corresponding TLI method. |
| 1707 | Optional<unsigned> getVScaleForTuning() const; |
| 1708 | |
| 1709 | /// \return An upper bound for the vectorization factors for both |
| 1710 | /// fixed and scalable vectorization, where the minimum-known number of |
| 1711 | /// elements is a power-of-2 larger than zero. If scalable vectorization is |
| 1712 | /// disabled or unsupported, then the scalable part will be equal to |
| 1713 | /// ElementCount::getScalable(0). |
| 1714 | FixedScalableVFPair computeFeasibleMaxVF(unsigned ConstTripCount, |
| 1715 | ElementCount UserVF, |
| 1716 | bool FoldTailByMasking); |
| 1717 | |
| 1718 | /// \return the maximized element count based on the targets vector |
| 1719 | /// registers and the loop trip-count, but limited to a maximum safe VF. |
| 1720 | /// This is a helper function of computeFeasibleMaxVF. |
| 1721 | /// FIXME: MaxSafeVF is currently passed by reference to avoid some obscure |
| 1722 | /// issue that occurred on one of the buildbots which cannot be reproduced |
| 1723 | /// without having access to the properietary compiler (see comments on |
| 1724 | /// D98509). The issue is currently under investigation and this workaround |
| 1725 | /// will be removed as soon as possible. |
| 1726 | ElementCount getMaximizedVFForTarget(unsigned ConstTripCount, |
| 1727 | unsigned SmallestType, |
| 1728 | unsigned WidestType, |
| 1729 | const ElementCount &MaxSafeVF, |
| 1730 | bool FoldTailByMasking); |
| 1731 | |
| 1732 | /// \return the maximum legal scalable VF, based on the safe max number |
| 1733 | /// of elements. |
| 1734 | ElementCount getMaxLegalScalableVF(unsigned MaxSafeElements); |
| 1735 | |
| 1736 | /// The vectorization cost is a combination of the cost itself and a boolean |
| 1737 | /// indicating whether any of the contributing operations will actually |
| 1738 | /// operate on vector values after type legalization in the backend. If this |
| 1739 | /// latter value is false, then all operations will be scalarized (i.e. no |
| 1740 | /// vectorization has actually taken place). |
| 1741 | using VectorizationCostTy = std::pair<InstructionCost, bool>; |
| 1742 | |
| 1743 | /// Returns the expected execution cost. The unit of the cost does |
| 1744 | /// not matter because we use the 'cost' units to compare different |
| 1745 | /// vector widths. The cost that is returned is *not* normalized by |
| 1746 | /// the factor width. If \p Invalid is not nullptr, this function |
| 1747 | /// will add a pair(Instruction*, ElementCount) to \p Invalid for |
| 1748 | /// each instruction that has an Invalid cost for the given VF. |
| 1749 | using InstructionVFPair = std::pair<Instruction *, ElementCount>; |
| 1750 | VectorizationCostTy |
| 1751 | expectedCost(ElementCount VF, |
| 1752 | SmallVectorImpl<InstructionVFPair> *Invalid = nullptr); |
| 1753 | |
| 1754 | /// Returns the execution time cost of an instruction for a given vector |
| 1755 | /// width. Vector width of one means scalar. |
| 1756 | VectorizationCostTy getInstructionCost(Instruction *I, ElementCount VF); |
| 1757 | |
| 1758 | /// The cost-computation logic from getInstructionCost which provides |
| 1759 | /// the vector type as an output parameter. |
| 1760 | InstructionCost getInstructionCost(Instruction *I, ElementCount VF, |
| 1761 | Type *&VectorTy); |
| 1762 | |
| 1763 | /// Return the cost of instructions in an inloop reduction pattern, if I is |
| 1764 | /// part of that pattern. |
| 1765 | Optional<InstructionCost> |
| 1766 | getReductionPatternCost(Instruction *I, ElementCount VF, Type *VectorTy, |
| 1767 | TTI::TargetCostKind CostKind); |
| 1768 | |
| 1769 | /// Calculate vectorization cost of memory instruction \p I. |
| 1770 | InstructionCost getMemoryInstructionCost(Instruction *I, ElementCount VF); |
| 1771 | |
| 1772 | /// The cost computation for scalarized memory instruction. |
| 1773 | InstructionCost getMemInstScalarizationCost(Instruction *I, ElementCount VF); |
| 1774 | |
| 1775 | /// The cost computation for interleaving group of memory instructions. |
| 1776 | InstructionCost getInterleaveGroupCost(Instruction *I, ElementCount VF); |
| 1777 | |
| 1778 | /// The cost computation for Gather/Scatter instruction. |
| 1779 | InstructionCost getGatherScatterCost(Instruction *I, ElementCount VF); |
| 1780 | |
| 1781 | /// The cost computation for widening instruction \p I with consecutive |
| 1782 | /// memory access. |
| 1783 | InstructionCost getConsecutiveMemOpCost(Instruction *I, ElementCount VF); |
| 1784 | |
| 1785 | /// The cost calculation for Load/Store instruction \p I with uniform pointer - |
| 1786 | /// Load: scalar load + broadcast. |
| 1787 | /// Store: scalar store + (loop invariant value stored? 0 : extract of last |
| 1788 | /// element) |
| 1789 | InstructionCost getUniformMemOpCost(Instruction *I, ElementCount VF); |
| 1790 | |
| 1791 | /// Estimate the overhead of scalarizing an instruction. This is a |
| 1792 | /// convenience wrapper for the type-based getScalarizationOverhead API. |
| 1793 | InstructionCost getScalarizationOverhead(Instruction *I, |
| 1794 | ElementCount VF) const; |
| 1795 | |
| 1796 | /// Returns whether the instruction is a load or store and will be a emitted |
| 1797 | /// as a vector operation. |
| 1798 | bool isConsecutiveLoadOrStore(Instruction *I); |
| 1799 | |
| 1800 | /// Returns true if an artificially high cost for emulated masked memrefs |
| 1801 | /// should be used. |
| 1802 | bool useEmulatedMaskMemRefHack(Instruction *I, ElementCount VF); |
| 1803 | |
| 1804 | /// Map of scalar integer values to the smallest bitwidth they can be legally |
| 1805 | /// represented as. The vector equivalents of these values should be truncated |
| 1806 | /// to this type. |
| 1807 | MapVector<Instruction *, uint64_t> MinBWs; |
| 1808 | |
| 1809 | /// A type representing the costs for instructions if they were to be |
| 1810 | /// scalarized rather than vectorized. The entries are Instruction-Cost |
| 1811 | /// pairs. |
| 1812 | using ScalarCostsTy = DenseMap<Instruction *, InstructionCost>; |
| 1813 | |
| 1814 | /// A set containing all BasicBlocks that are known to present after |
| 1815 | /// vectorization as a predicated block. |
| 1816 | SmallPtrSet<BasicBlock *, 4> PredicatedBBsAfterVectorization; |
| 1817 | |
| 1818 | /// Records whether it is allowed to have the original scalar loop execute at |
| 1819 | /// least once. This may be needed as a fallback loop in case runtime |
| 1820 | /// aliasing/dependence checks fail, or to handle the tail/remainder |
| 1821 | /// iterations when the trip count is unknown or doesn't divide by the VF, |
| 1822 | /// or as a peel-loop to handle gaps in interleave-groups. |
| 1823 | /// Under optsize and when the trip count is very small we don't allow any |
| 1824 | /// iterations to execute in the scalar loop. |
| 1825 | ScalarEpilogueLowering ScalarEpilogueStatus = CM_ScalarEpilogueAllowed; |
| 1826 | |
| 1827 | /// All blocks of loop are to be masked to fold tail of scalar iterations. |
| 1828 | bool FoldTailByMasking = false; |
| 1829 | |
| 1830 | /// A map holding scalar costs for different vectorization factors. The |
| 1831 | /// presence of a cost for an instruction in the mapping indicates that the |
| 1832 | /// instruction will be scalarized when vectorizing with the associated |
| 1833 | /// vectorization factor. The entries are VF-ScalarCostTy pairs. |
| 1834 | DenseMap<ElementCount, ScalarCostsTy> InstsToScalarize; |
| 1835 | |
| 1836 | /// Holds the instructions known to be uniform after vectorization. |
| 1837 | /// The data is collected per VF. |
| 1838 | DenseMap<ElementCount, SmallPtrSet<Instruction *, 4>> Uniforms; |
| 1839 | |
| 1840 | /// Holds the instructions known to be scalar after vectorization. |
| 1841 | /// The data is collected per VF. |
| 1842 | DenseMap<ElementCount, SmallPtrSet<Instruction *, 4>> Scalars; |
| 1843 | |
| 1844 | /// Holds the instructions (address computations) that are forced to be |
| 1845 | /// scalarized. |
| 1846 | DenseMap<ElementCount, SmallPtrSet<Instruction *, 4>> ForcedScalars; |
| 1847 | |
| 1848 | /// PHINodes of the reductions that should be expanded in-loop along with |
| 1849 | /// their associated chains of reduction operations, in program order from top |
| 1850 | /// (PHI) to bottom |
| 1851 | ReductionChainMap InLoopReductionChains; |
| 1852 | |
| 1853 | /// A Map of inloop reduction operations and their immediate chain operand. |
| 1854 | /// FIXME: This can be removed once reductions can be costed correctly in |
| 1855 | /// vplan. This was added to allow quick lookup to the inloop operations, |
| 1856 | /// without having to loop through InLoopReductionChains. |
| 1857 | DenseMap<Instruction *, Instruction *> InLoopReductionImmediateChains; |
| 1858 | |
| 1859 | /// Returns the expected difference in cost from scalarizing the expression |
| 1860 | /// feeding a predicated instruction \p PredInst. The instructions to |
| 1861 | /// scalarize and their scalar costs are collected in \p ScalarCosts. A |
| 1862 | /// non-negative return value implies the expression will be scalarized. |
| 1863 | /// Currently, only single-use chains are considered for scalarization. |
| 1864 | int computePredInstDiscount(Instruction *PredInst, ScalarCostsTy &ScalarCosts, |
| 1865 | ElementCount VF); |
| 1866 | |
| 1867 | /// Collect the instructions that are uniform after vectorization. An |
| 1868 | /// instruction is uniform if we represent it with a single scalar value in |
| 1869 | /// the vectorized loop corresponding to each vector iteration. Examples of |
| 1870 | /// uniform instructions include pointer operands of consecutive or |
| 1871 | /// interleaved memory accesses. Note that although uniformity implies an |
| 1872 | /// instruction will be scalar, the reverse is not true. In general, a |
| 1873 | /// scalarized instruction will be represented by VF scalar values in the |
| 1874 | /// vectorized loop, each corresponding to an iteration of the original |
| 1875 | /// scalar loop. |
| 1876 | void collectLoopUniforms(ElementCount VF); |
| 1877 | |
| 1878 | /// Collect the instructions that are scalar after vectorization. An |
| 1879 | /// instruction is scalar if it is known to be uniform or will be scalarized |
| 1880 | /// during vectorization. collectLoopScalars should only add non-uniform nodes |
| 1881 | /// to the list if they are used by a load/store instruction that is marked as |
| 1882 | /// CM_Scalarize. Non-uniform scalarized instructions will be represented by |
| 1883 | /// VF values in the vectorized loop, each corresponding to an iteration of |
| 1884 | /// the original scalar loop. |
| 1885 | void collectLoopScalars(ElementCount VF); |
| 1886 | |
| 1887 | /// Keeps cost model vectorization decision and cost for instructions. |
| 1888 | /// Right now it is used for memory instructions only. |
| 1889 | using DecisionList = DenseMap<std::pair<Instruction *, ElementCount>, |
| 1890 | std::pair<InstWidening, InstructionCost>>; |
| 1891 | |
| 1892 | DecisionList WideningDecisions; |
| 1893 | |
| 1894 | /// Returns true if \p V is expected to be vectorized and it needs to be |
| 1895 | /// extracted. |
| 1896 | bool needsExtract(Value *V, ElementCount VF) const { |
| 1897 | Instruction *I = dyn_cast<Instruction>(V); |
| 1898 | if (VF.isScalar() || !I || !TheLoop->contains(I) || |
| 1899 | TheLoop->isLoopInvariant(I)) |
| 1900 | return false; |
| 1901 | |
| 1902 | // Assume we can vectorize V (and hence we need extraction) if the |
| 1903 | // scalars are not computed yet. This can happen, because it is called |
| 1904 | // via getScalarizationOverhead from setCostBasedWideningDecision, before |
| 1905 | // the scalars are collected. That should be a safe assumption in most |
| 1906 | // cases, because we check if the operands have vectorizable types |
| 1907 | // beforehand in LoopVectorizationLegality. |
| 1908 | return Scalars.find(VF) == Scalars.end() || |
| 1909 | !isScalarAfterVectorization(I, VF); |
| 1910 | }; |
| 1911 | |
| 1912 | /// Returns a range containing only operands needing to be extracted. |
| 1913 | SmallVector<Value *, 4> filterExtractingOperands(Instruction::op_range Ops, |
| 1914 | ElementCount VF) const { |
| 1915 | return SmallVector<Value *, 4>(make_filter_range( |
| 1916 | Ops, [this, VF](Value *V) { return this->needsExtract(V, VF); })); |
| 1917 | } |
| 1918 | |
| 1919 | /// Determines if we have the infrastructure to vectorize loop \p L and its |
| 1920 | /// epilogue, assuming the main loop is vectorized by \p VF. |
| 1921 | bool isCandidateForEpilogueVectorization(const Loop &L, |
| 1922 | const ElementCount VF) const; |
| 1923 | |
| 1924 | /// Returns true if epilogue vectorization is considered profitable, and |
| 1925 | /// false otherwise. |
| 1926 | /// \p VF is the vectorization factor chosen for the original loop. |
| 1927 | bool isEpilogueVectorizationProfitable(const ElementCount VF) const; |
| 1928 | |
| 1929 | public: |
| 1930 | /// The loop that we evaluate. |
| 1931 | Loop *TheLoop; |
| 1932 | |
| 1933 | /// Predicated scalar evolution analysis. |
| 1934 | PredicatedScalarEvolution &PSE; |
| 1935 | |
| 1936 | /// Loop Info analysis. |
| 1937 | LoopInfo *LI; |
| 1938 | |
| 1939 | /// Vectorization legality. |
| 1940 | LoopVectorizationLegality *Legal; |
| 1941 | |
| 1942 | /// Vector target information. |
| 1943 | const TargetTransformInfo &TTI; |
| 1944 | |
| 1945 | /// Target Library Info. |
| 1946 | const TargetLibraryInfo *TLI; |
| 1947 | |
| 1948 | /// Demanded bits analysis. |
| 1949 | DemandedBits *DB; |
| 1950 | |
| 1951 | /// Assumption cache. |
| 1952 | AssumptionCache *AC; |
| 1953 | |
| 1954 | /// Interface to emit optimization remarks. |
| 1955 | OptimizationRemarkEmitter *ORE; |
| 1956 | |
| 1957 | const Function *TheFunction; |
| 1958 | |
| 1959 | /// Loop Vectorize Hint. |
| 1960 | const LoopVectorizeHints *Hints; |
| 1961 | |
| 1962 | /// The interleave access information contains groups of interleaved accesses |
| 1963 | /// with the same stride and close to each other. |
| 1964 | InterleavedAccessInfo &InterleaveInfo; |
| 1965 | |
| 1966 | /// Values to ignore in the cost model. |
| 1967 | SmallPtrSet<const Value *, 16> ValuesToIgnore; |
| 1968 | |
| 1969 | /// Values to ignore in the cost model when VF > 1. |
| 1970 | SmallPtrSet<const Value *, 16> VecValuesToIgnore; |
| 1971 | |
| 1972 | /// All element types found in the loop. |
| 1973 | SmallPtrSet<Type *, 16> ElementTypesInLoop; |
| 1974 | |
| 1975 | /// Profitable vector factors. |
| 1976 | SmallVector<VectorizationFactor, 8> ProfitableVFs; |
| 1977 | }; |
| 1978 | } // end namespace llvm |
| 1979 | |
| 1980 | /// Helper struct to manage generating runtime checks for vectorization. |
| 1981 | /// |
| 1982 | /// The runtime checks are created up-front in temporary blocks to allow better |
| 1983 | /// estimating the cost and un-linked from the existing IR. After deciding to |
| 1984 | /// vectorize, the checks are moved back. If deciding not to vectorize, the |
| 1985 | /// temporary blocks are completely removed. |
| 1986 | class GeneratedRTChecks { |
| 1987 | /// Basic block which contains the generated SCEV checks, if any. |
| 1988 | BasicBlock *SCEVCheckBlock = nullptr; |
| 1989 | |
| 1990 | /// The value representing the result of the generated SCEV checks. If it is |
| 1991 | /// nullptr, either no SCEV checks have been generated or they have been used. |
| 1992 | Value *SCEVCheckCond = nullptr; |
| 1993 | |
| 1994 | /// Basic block which contains the generated memory runtime checks, if any. |
| 1995 | BasicBlock *MemCheckBlock = nullptr; |
| 1996 | |
| 1997 | /// The value representing the result of the generated memory runtime checks. |
| 1998 | /// If it is nullptr, either no memory runtime checks have been generated or |
| 1999 | /// they have been used. |
| 2000 | Value *MemRuntimeCheckCond = nullptr; |
| 2001 | |
| 2002 | DominatorTree *DT; |
| 2003 | LoopInfo *LI; |
| 2004 | |
| 2005 | SCEVExpander SCEVExp; |
| 2006 | SCEVExpander MemCheckExp; |
| 2007 | |
| 2008 | public: |
| 2009 | GeneratedRTChecks(ScalarEvolution &SE, DominatorTree *DT, LoopInfo *LI, |
| 2010 | const DataLayout &DL) |
| 2011 | : DT(DT), LI(LI), SCEVExp(SE, DL, "scev.check"), |
| 2012 | MemCheckExp(SE, DL, "scev.check") {} |
| 2013 | |
| 2014 | /// Generate runtime checks in SCEVCheckBlock and MemCheckBlock, so we can |
| 2015 | /// accurately estimate the cost of the runtime checks. The blocks are |
| 2016 | /// un-linked from the IR and is added back during vector code generation. If |
| 2017 | /// there is no vector code generation, the check blocks are removed |
| 2018 | /// completely. |
| 2019 | void Create(Loop *L, const LoopAccessInfo &LAI, |
| 2020 | const SCEVUnionPredicate &UnionPred) { |
| 2021 | |
| 2022 | BasicBlock *LoopHeader = L->getHeader(); |
| 2023 | BasicBlock *Preheader = L->getLoopPreheader(); |
| 2024 | |
| 2025 | // Use SplitBlock to create blocks for SCEV & memory runtime checks to |
| 2026 | // ensure the blocks are properly added to LoopInfo & DominatorTree. Those |
| 2027 | // may be used by SCEVExpander. The blocks will be un-linked from their |
| 2028 | // predecessors and removed from LI & DT at the end of the function. |
| 2029 | if (!UnionPred.isAlwaysTrue()) { |
| 2030 | SCEVCheckBlock = SplitBlock(Preheader, Preheader->getTerminator(), DT, LI, |
| 2031 | nullptr, "vector.scevcheck"); |
| 2032 | |
| 2033 | SCEVCheckCond = SCEVExp.expandCodeForPredicate( |
| 2034 | &UnionPred, SCEVCheckBlock->getTerminator()); |
| 2035 | } |
| 2036 | |
| 2037 | const auto &RtPtrChecking = *LAI.getRuntimePointerChecking(); |
| 2038 | if (RtPtrChecking.Need) { |
| 2039 | auto *Pred = SCEVCheckBlock ? SCEVCheckBlock : Preheader; |
| 2040 | MemCheckBlock = SplitBlock(Pred, Pred->getTerminator(), DT, LI, nullptr, |
| 2041 | "vector.memcheck"); |
| 2042 | |
| 2043 | MemRuntimeCheckCond = |
| 2044 | addRuntimeChecks(MemCheckBlock->getTerminator(), L, |
| 2045 | RtPtrChecking.getChecks(), MemCheckExp); |
| 2046 | assert(MemRuntimeCheckCond &&(static_cast <bool> (MemRuntimeCheckCond && "no RT checks generated although RtPtrChecking " "claimed checks are required") ? void (0) : __assert_fail ("MemRuntimeCheckCond && \"no RT checks generated although RtPtrChecking \" \"claimed checks are required\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2048, __extension__ __PRETTY_FUNCTION__)) |
| 2047 | "no RT checks generated although RtPtrChecking "(static_cast <bool> (MemRuntimeCheckCond && "no RT checks generated although RtPtrChecking " "claimed checks are required") ? void (0) : __assert_fail ("MemRuntimeCheckCond && \"no RT checks generated although RtPtrChecking \" \"claimed checks are required\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2048, __extension__ __PRETTY_FUNCTION__)) |
| 2048 | "claimed checks are required")(static_cast <bool> (MemRuntimeCheckCond && "no RT checks generated although RtPtrChecking " "claimed checks are required") ? void (0) : __assert_fail ("MemRuntimeCheckCond && \"no RT checks generated although RtPtrChecking \" \"claimed checks are required\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2048, __extension__ __PRETTY_FUNCTION__)); |
| 2049 | } |
| 2050 | |
| 2051 | if (!MemCheckBlock && !SCEVCheckBlock) |
| 2052 | return; |
| 2053 | |
| 2054 | // Unhook the temporary block with the checks, update various places |
| 2055 | // accordingly. |
| 2056 | if (SCEVCheckBlock) |
| 2057 | SCEVCheckBlock->replaceAllUsesWith(Preheader); |
| 2058 | if (MemCheckBlock) |
| 2059 | MemCheckBlock->replaceAllUsesWith(Preheader); |
| 2060 | |
| 2061 | if (SCEVCheckBlock) { |
| 2062 | SCEVCheckBlock->getTerminator()->moveBefore(Preheader->getTerminator()); |
| 2063 | new UnreachableInst(Preheader->getContext(), SCEVCheckBlock); |
| 2064 | Preheader->getTerminator()->eraseFromParent(); |
| 2065 | } |
| 2066 | if (MemCheckBlock) { |
| 2067 | MemCheckBlock->getTerminator()->moveBefore(Preheader->getTerminator()); |
| 2068 | new UnreachableInst(Preheader->getContext(), MemCheckBlock); |
| 2069 | Preheader->getTerminator()->eraseFromParent(); |
| 2070 | } |
| 2071 | |
| 2072 | DT->changeImmediateDominator(LoopHeader, Preheader); |
| 2073 | if (MemCheckBlock) { |
| 2074 | DT->eraseNode(MemCheckBlock); |
| 2075 | LI->removeBlock(MemCheckBlock); |
| 2076 | } |
| 2077 | if (SCEVCheckBlock) { |
| 2078 | DT->eraseNode(SCEVCheckBlock); |
| 2079 | LI->removeBlock(SCEVCheckBlock); |
| 2080 | } |
| 2081 | } |
| 2082 | |
| 2083 | /// Remove the created SCEV & memory runtime check blocks & instructions, if |
| 2084 | /// unused. |
| 2085 | ~GeneratedRTChecks() { |
| 2086 | SCEVExpanderCleaner SCEVCleaner(SCEVExp); |
| 2087 | SCEVExpanderCleaner MemCheckCleaner(MemCheckExp); |
| 2088 | if (!SCEVCheckCond) |
| 2089 | SCEVCleaner.markResultUsed(); |
| 2090 | |
| 2091 | if (!MemRuntimeCheckCond) |
| 2092 | MemCheckCleaner.markResultUsed(); |
| 2093 | |
| 2094 | if (MemRuntimeCheckCond) { |
| 2095 | auto &SE = *MemCheckExp.getSE(); |
| 2096 | // Memory runtime check generation creates compares that use expanded |
| 2097 | // values. Remove them before running the SCEVExpanderCleaners. |
| 2098 | for (auto &I : make_early_inc_range(reverse(*MemCheckBlock))) { |
| 2099 | if (MemCheckExp.isInsertedInstruction(&I)) |
| 2100 | continue; |
| 2101 | SE.forgetValue(&I); |
| 2102 | I.eraseFromParent(); |
| 2103 | } |
| 2104 | } |
| 2105 | MemCheckCleaner.cleanup(); |
| 2106 | SCEVCleaner.cleanup(); |
| 2107 | |
| 2108 | if (SCEVCheckCond) |
| 2109 | SCEVCheckBlock->eraseFromParent(); |
| 2110 | if (MemRuntimeCheckCond) |
| 2111 | MemCheckBlock->eraseFromParent(); |
| 2112 | } |
| 2113 | |
| 2114 | /// Adds the generated SCEVCheckBlock before \p LoopVectorPreHeader and |
| 2115 | /// adjusts the branches to branch to the vector preheader or \p Bypass, |
| 2116 | /// depending on the generated condition. |
| 2117 | BasicBlock *emitSCEVChecks(Loop *L, BasicBlock *Bypass, |
| 2118 | BasicBlock *LoopVectorPreHeader, |
| 2119 | BasicBlock *LoopExitBlock) { |
| 2120 | if (!SCEVCheckCond) |
| 2121 | return nullptr; |
| 2122 | if (auto *C = dyn_cast<ConstantInt>(SCEVCheckCond)) |
| 2123 | if (C->isZero()) |
| 2124 | return nullptr; |
| 2125 | |
| 2126 | auto *Pred = LoopVectorPreHeader->getSinglePredecessor(); |
| 2127 | |
| 2128 | BranchInst::Create(LoopVectorPreHeader, SCEVCheckBlock); |
| 2129 | // Create new preheader for vector loop. |
| 2130 | if (auto *PL = LI->getLoopFor(LoopVectorPreHeader)) |
| 2131 | PL->addBasicBlockToLoop(SCEVCheckBlock, *LI); |
| 2132 | |
| 2133 | SCEVCheckBlock->getTerminator()->eraseFromParent(); |
| 2134 | SCEVCheckBlock->moveBefore(LoopVectorPreHeader); |
| 2135 | Pred->getTerminator()->replaceSuccessorWith(LoopVectorPreHeader, |
| 2136 | SCEVCheckBlock); |
| 2137 | |
| 2138 | DT->addNewBlock(SCEVCheckBlock, Pred); |
| 2139 | DT->changeImmediateDominator(LoopVectorPreHeader, SCEVCheckBlock); |
| 2140 | |
| 2141 | ReplaceInstWithInst( |
| 2142 | SCEVCheckBlock->getTerminator(), |
| 2143 | BranchInst::Create(Bypass, LoopVectorPreHeader, SCEVCheckCond)); |
| 2144 | // Mark the check as used, to prevent it from being removed during cleanup. |
| 2145 | SCEVCheckCond = nullptr; |
| 2146 | return SCEVCheckBlock; |
| 2147 | } |
| 2148 | |
| 2149 | /// Adds the generated MemCheckBlock before \p LoopVectorPreHeader and adjusts |
| 2150 | /// the branches to branch to the vector preheader or \p Bypass, depending on |
| 2151 | /// the generated condition. |
| 2152 | BasicBlock *emitMemRuntimeChecks(Loop *L, BasicBlock *Bypass, |
| 2153 | BasicBlock *LoopVectorPreHeader) { |
| 2154 | // Check if we generated code that checks in runtime if arrays overlap. |
| 2155 | if (!MemRuntimeCheckCond) |
| 2156 | return nullptr; |
| 2157 | |
| 2158 | auto *Pred = LoopVectorPreHeader->getSinglePredecessor(); |
| 2159 | Pred->getTerminator()->replaceSuccessorWith(LoopVectorPreHeader, |
| 2160 | MemCheckBlock); |
| 2161 | |
| 2162 | DT->addNewBlock(MemCheckBlock, Pred); |
| 2163 | DT->changeImmediateDominator(LoopVectorPreHeader, MemCheckBlock); |
| 2164 | MemCheckBlock->moveBefore(LoopVectorPreHeader); |
| 2165 | |
| 2166 | if (auto *PL = LI->getLoopFor(LoopVectorPreHeader)) |
| 2167 | PL->addBasicBlockToLoop(MemCheckBlock, *LI); |
| 2168 | |
| 2169 | ReplaceInstWithInst( |
| 2170 | MemCheckBlock->getTerminator(), |
| 2171 | BranchInst::Create(Bypass, LoopVectorPreHeader, MemRuntimeCheckCond)); |
| 2172 | MemCheckBlock->getTerminator()->setDebugLoc( |
| 2173 | Pred->getTerminator()->getDebugLoc()); |
| 2174 | |
| 2175 | // Mark the check as used, to prevent it from being removed during cleanup. |
| 2176 | MemRuntimeCheckCond = nullptr; |
| 2177 | return MemCheckBlock; |
| 2178 | } |
| 2179 | }; |
| 2180 | |
| 2181 | // Return true if \p OuterLp is an outer loop annotated with hints for explicit |
| 2182 | // vectorization. The loop needs to be annotated with #pragma omp simd |
| 2183 | // simdlen(#) or #pragma clang vectorize(enable) vectorize_width(#). If the |
| 2184 | // vector length information is not provided, vectorization is not considered |
| 2185 | // explicit. Interleave hints are not allowed either. These limitations will be |
| 2186 | // relaxed in the future. |
| 2187 | // Please, note that we are currently forced to abuse the pragma 'clang |
| 2188 | // vectorize' semantics. This pragma provides *auto-vectorization hints* |
| 2189 | // (i.e., LV must check that vectorization is legal) whereas pragma 'omp simd' |
| 2190 | // provides *explicit vectorization hints* (LV can bypass legal checks and |
| 2191 | // assume that vectorization is legal). However, both hints are implemented |
| 2192 | // using the same metadata (llvm.loop.vectorize, processed by |
| 2193 | // LoopVectorizeHints). This will be fixed in the future when the native IR |
| 2194 | // representation for pragma 'omp simd' is introduced. |
| 2195 | static bool isExplicitVecOuterLoop(Loop *OuterLp, |
| 2196 | OptimizationRemarkEmitter *ORE) { |
| 2197 | assert(!OuterLp->isInnermost() && "This is not an outer loop")(static_cast <bool> (!OuterLp->isInnermost() && "This is not an outer loop") ? void (0) : __assert_fail ("!OuterLp->isInnermost() && \"This is not an outer loop\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2197, __extension__ __PRETTY_FUNCTION__)); |
| 2198 | LoopVectorizeHints Hints(OuterLp, true /*DisableInterleaving*/, *ORE); |
| 2199 | |
| 2200 | // Only outer loops with an explicit vectorization hint are supported. |
| 2201 | // Unannotated outer loops are ignored. |
| 2202 | if (Hints.getForce() == LoopVectorizeHints::FK_Undefined) |
| 2203 | return false; |
| 2204 | |
| 2205 | Function *Fn = OuterLp->getHeader()->getParent(); |
| 2206 | if (!Hints.allowVectorization(Fn, OuterLp, |
| 2207 | true /*VectorizeOnlyWhenForced*/)) { |
| 2208 | LLVM_DEBUG(dbgs() << "LV: Loop hints prevent outer loop vectorization.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints prevent outer loop vectorization.\n" ; } } while (false); |
| 2209 | return false; |
| 2210 | } |
| 2211 | |
| 2212 | if (Hints.getInterleave() > 1) { |
| 2213 | // TODO: Interleave support is future work. |
| 2214 | LLVM_DEBUG(dbgs() << "LV: Not vectorizing: Interleave is not supported for "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not vectorizing: Interleave is not supported for " "outer loops.\n"; } } while (false) |
| 2215 | "outer loops.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not vectorizing: Interleave is not supported for " "outer loops.\n"; } } while (false); |
| 2216 | Hints.emitRemarkWithHints(); |
| 2217 | return false; |
| 2218 | } |
| 2219 | |
| 2220 | return true; |
| 2221 | } |
| 2222 | |
| 2223 | static void collectSupportedLoops(Loop &L, LoopInfo *LI, |
| 2224 | OptimizationRemarkEmitter *ORE, |
| 2225 | SmallVectorImpl<Loop *> &V) { |
| 2226 | // Collect inner loops and outer loops without irreducible control flow. For |
| 2227 | // now, only collect outer loops that have explicit vectorization hints. If we |
| 2228 | // are stress testing the VPlan H-CFG construction, we collect the outermost |
| 2229 | // loop of every loop nest. |
| 2230 | if (L.isInnermost() || VPlanBuildStressTest || |
| 2231 | (EnableVPlanNativePath && isExplicitVecOuterLoop(&L, ORE))) { |
| 2232 | LoopBlocksRPO RPOT(&L); |
| 2233 | RPOT.perform(LI); |
| 2234 | if (!containsIrreducibleCFG<const BasicBlock *>(RPOT, *LI)) { |
| 2235 | V.push_back(&L); |
| 2236 | // TODO: Collect inner loops inside marked outer loops in case |
| 2237 | // vectorization fails for the outer loop. Do not invoke |
| 2238 | // 'containsIrreducibleCFG' again for inner loops when the outer loop is |
| 2239 | // already known to be reducible. We can use an inherited attribute for |
| 2240 | // that. |
| 2241 | return; |
| 2242 | } |
| 2243 | } |
| 2244 | for (Loop *InnerL : L) |
| 2245 | collectSupportedLoops(*InnerL, LI, ORE, V); |
| 2246 | } |
| 2247 | |
| 2248 | namespace { |
| 2249 | |
| 2250 | /// The LoopVectorize Pass. |
| 2251 | struct LoopVectorize : public FunctionPass { |
| 2252 | /// Pass identification, replacement for typeid |
| 2253 | static char ID; |
| 2254 | |
| 2255 | LoopVectorizePass Impl; |
| 2256 | |
| 2257 | explicit LoopVectorize(bool InterleaveOnlyWhenForced = false, |
| 2258 | bool VectorizeOnlyWhenForced = false) |
| 2259 | : FunctionPass(ID), |
| 2260 | Impl({InterleaveOnlyWhenForced, VectorizeOnlyWhenForced}) { |
| 2261 | initializeLoopVectorizePass(*PassRegistry::getPassRegistry()); |
| 2262 | } |
| 2263 | |
| 2264 | bool runOnFunction(Function &F) override { |
| 2265 | if (skipFunction(F)) |
| 2266 | return false; |
| 2267 | |
| 2268 | auto *SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE(); |
| 2269 | auto *LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo(); |
| 2270 | auto *TTI = &getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F); |
| 2271 | auto *DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree(); |
| 2272 | auto *BFI = &getAnalysis<BlockFrequencyInfoWrapperPass>().getBFI(); |
| 2273 | auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>(); |
| 2274 | auto *TLI = TLIP ? &TLIP->getTLI(F) : nullptr; |
| 2275 | auto *AA = &getAnalysis<AAResultsWrapperPass>().getAAResults(); |
| 2276 | auto *AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F); |
| 2277 | auto *LAA = &getAnalysis<LoopAccessLegacyAnalysis>(); |
| 2278 | auto *DB = &getAnalysis<DemandedBitsWrapperPass>().getDemandedBits(); |
| 2279 | auto *ORE = &getAnalysis<OptimizationRemarkEmitterWrapperPass>().getORE(); |
| 2280 | auto *PSI = &getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI(); |
| 2281 | |
| 2282 | std::function<const LoopAccessInfo &(Loop &)> GetLAA = |
| 2283 | [&](Loop &L) -> const LoopAccessInfo & { return LAA->getInfo(&L); }; |
| 2284 | |
| 2285 | return Impl.runImpl(F, *SE, *LI, *TTI, *DT, *BFI, TLI, *DB, *AA, *AC, |
| 2286 | GetLAA, *ORE, PSI).MadeAnyChange; |
| 2287 | } |
| 2288 | |
| 2289 | void getAnalysisUsage(AnalysisUsage &AU) const override { |
| 2290 | AU.addRequired<AssumptionCacheTracker>(); |
| 2291 | AU.addRequired<BlockFrequencyInfoWrapperPass>(); |
| 2292 | AU.addRequired<DominatorTreeWrapperPass>(); |
| 2293 | AU.addRequired<LoopInfoWrapperPass>(); |
| 2294 | AU.addRequired<ScalarEvolutionWrapperPass>(); |
| 2295 | AU.addRequired<TargetTransformInfoWrapperPass>(); |
| 2296 | AU.addRequired<AAResultsWrapperPass>(); |
| 2297 | AU.addRequired<LoopAccessLegacyAnalysis>(); |
| 2298 | AU.addRequired<DemandedBitsWrapperPass>(); |
| 2299 | AU.addRequired<OptimizationRemarkEmitterWrapperPass>(); |
| 2300 | AU.addRequired<InjectTLIMappingsLegacy>(); |
| 2301 | |
| 2302 | // We currently do not preserve loopinfo/dominator analyses with outer loop |
| 2303 | // vectorization. Until this is addressed, mark these analyses as preserved |
| 2304 | // only for non-VPlan-native path. |
| 2305 | // TODO: Preserve Loop and Dominator analyses for VPlan-native path. |
| 2306 | if (!EnableVPlanNativePath) { |
| 2307 | AU.addPreserved<LoopInfoWrapperPass>(); |
| 2308 | AU.addPreserved<DominatorTreeWrapperPass>(); |
| 2309 | } |
| 2310 | |
| 2311 | AU.addPreserved<BasicAAWrapperPass>(); |
| 2312 | AU.addPreserved<GlobalsAAWrapperPass>(); |
| 2313 | AU.addRequired<ProfileSummaryInfoWrapperPass>(); |
| 2314 | } |
| 2315 | }; |
| 2316 | |
| 2317 | } // end anonymous namespace |
| 2318 | |
| 2319 | //===----------------------------------------------------------------------===// |
| 2320 | // Implementation of LoopVectorizationLegality, InnerLoopVectorizer and |
| 2321 | // LoopVectorizationCostModel and LoopVectorizationPlanner. |
| 2322 | //===----------------------------------------------------------------------===// |
| 2323 | |
| 2324 | Value *InnerLoopVectorizer::getBroadcastInstrs(Value *V) { |
| 2325 | // We need to place the broadcast of invariant variables outside the loop, |
| 2326 | // but only if it's proven safe to do so. Else, broadcast will be inside |
| 2327 | // vector loop body. |
| 2328 | Instruction *Instr = dyn_cast<Instruction>(V); |
| 2329 | bool SafeToHoist = OrigLoop->isLoopInvariant(V) && |
| 2330 | (!Instr || |
| 2331 | DT->dominates(Instr->getParent(), LoopVectorPreHeader)); |
| 2332 | // Place the code for broadcasting invariant variables in the new preheader. |
| 2333 | IRBuilder<>::InsertPointGuard Guard(Builder); |
| 2334 | if (SafeToHoist) |
| 2335 | Builder.SetInsertPoint(LoopVectorPreHeader->getTerminator()); |
| 2336 | |
| 2337 | // Broadcast the scalar into all locations in the vector. |
| 2338 | Value *Shuf = Builder.CreateVectorSplat(VF, V, "broadcast"); |
| 2339 | |
| 2340 | return Shuf; |
| 2341 | } |
| 2342 | |
| 2343 | /// This function adds |
| 2344 | /// (StartIdx * Step, (StartIdx + 1) * Step, (StartIdx + 2) * Step, ...) |
| 2345 | /// to each vector element of Val. The sequence starts at StartIndex. |
| 2346 | /// \p Opcode is relevant for FP induction variable. |
| 2347 | static Value *getStepVector(Value *Val, Value *StartIdx, Value *Step, |
| 2348 | Instruction::BinaryOps BinOp, ElementCount VF, |
| 2349 | IRBuilder<> &Builder) { |
| 2350 | assert(VF.isVector() && "only vector VFs are supported")(static_cast <bool> (VF.isVector() && "only vector VFs are supported" ) ? void (0) : __assert_fail ("VF.isVector() && \"only vector VFs are supported\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2350, __extension__ __PRETTY_FUNCTION__)); |
| 2351 | |
| 2352 | // Create and check the types. |
| 2353 | auto *ValVTy = cast<VectorType>(Val->getType()); |
| 2354 | ElementCount VLen = ValVTy->getElementCount(); |
| 2355 | |
| 2356 | Type *STy = Val->getType()->getScalarType(); |
| 2357 | assert((STy->isIntegerTy() || STy->isFloatingPointTy()) &&(static_cast <bool> ((STy->isIntegerTy() || STy-> isFloatingPointTy()) && "Induction Step must be an integer or FP" ) ? void (0) : __assert_fail ("(STy->isIntegerTy() || STy->isFloatingPointTy()) && \"Induction Step must be an integer or FP\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2358, __extension__ __PRETTY_FUNCTION__)) |
| 2358 | "Induction Step must be an integer or FP")(static_cast <bool> ((STy->isIntegerTy() || STy-> isFloatingPointTy()) && "Induction Step must be an integer or FP" ) ? void (0) : __assert_fail ("(STy->isIntegerTy() || STy->isFloatingPointTy()) && \"Induction Step must be an integer or FP\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2358, __extension__ __PRETTY_FUNCTION__)); |
| 2359 | assert(Step->getType() == STy && "Step has wrong type")(static_cast <bool> (Step->getType() == STy && "Step has wrong type") ? void (0) : __assert_fail ("Step->getType() == STy && \"Step has wrong type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2359, __extension__ __PRETTY_FUNCTION__)); |
| 2360 | |
| 2361 | SmallVector<Constant *, 8> Indices; |
| 2362 | |
| 2363 | // Create a vector of consecutive numbers from zero to VF. |
| 2364 | VectorType *InitVecValVTy = ValVTy; |
| 2365 | Type *InitVecValSTy = STy; |
Value stored to 'InitVecValSTy' during its initialization is never read | |
| 2366 | if (STy->isFloatingPointTy()) { |
| 2367 | InitVecValSTy = |
| 2368 | IntegerType::get(STy->getContext(), STy->getScalarSizeInBits()); |
| 2369 | InitVecValVTy = VectorType::get(InitVecValSTy, VLen); |
| 2370 | } |
| 2371 | Value *InitVec = Builder.CreateStepVector(InitVecValVTy); |
| 2372 | |
| 2373 | // Splat the StartIdx |
| 2374 | Value *StartIdxSplat = Builder.CreateVectorSplat(VLen, StartIdx); |
| 2375 | |
| 2376 | if (STy->isIntegerTy()) { |
| 2377 | InitVec = Builder.CreateAdd(InitVec, StartIdxSplat); |
| 2378 | Step = Builder.CreateVectorSplat(VLen, Step); |
| 2379 | assert(Step->getType() == Val->getType() && "Invalid step vec")(static_cast <bool> (Step->getType() == Val->getType () && "Invalid step vec") ? void (0) : __assert_fail ( "Step->getType() == Val->getType() && \"Invalid step vec\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2379, __extension__ __PRETTY_FUNCTION__)); |
| 2380 | // FIXME: The newly created binary instructions should contain nsw/nuw |
| 2381 | // flags, which can be found from the original scalar operations. |
| 2382 | Step = Builder.CreateMul(InitVec, Step); |
| 2383 | return Builder.CreateAdd(Val, Step, "induction"); |
| 2384 | } |
| 2385 | |
| 2386 | // Floating point induction. |
| 2387 | assert((BinOp == Instruction::FAdd || BinOp == Instruction::FSub) &&(static_cast <bool> ((BinOp == Instruction::FAdd || BinOp == Instruction::FSub) && "Binary Opcode should be specified for FP induction" ) ? void (0) : __assert_fail ("(BinOp == Instruction::FAdd || BinOp == Instruction::FSub) && \"Binary Opcode should be specified for FP induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2388, __extension__ __PRETTY_FUNCTION__)) |
| 2388 | "Binary Opcode should be specified for FP induction")(static_cast <bool> ((BinOp == Instruction::FAdd || BinOp == Instruction::FSub) && "Binary Opcode should be specified for FP induction" ) ? void (0) : __assert_fail ("(BinOp == Instruction::FAdd || BinOp == Instruction::FSub) && \"Binary Opcode should be specified for FP induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2388, __extension__ __PRETTY_FUNCTION__)); |
| 2389 | InitVec = Builder.CreateUIToFP(InitVec, ValVTy); |
| 2390 | InitVec = Builder.CreateFAdd(InitVec, StartIdxSplat); |
| 2391 | |
| 2392 | Step = Builder.CreateVectorSplat(VLen, Step); |
| 2393 | Value *MulOp = Builder.CreateFMul(InitVec, Step); |
| 2394 | return Builder.CreateBinOp(BinOp, Val, MulOp, "induction"); |
| 2395 | } |
| 2396 | |
| 2397 | void InnerLoopVectorizer::createVectorIntOrFpInductionPHI( |
| 2398 | const InductionDescriptor &II, Value *Step, Value *Start, |
| 2399 | Instruction *EntryVal, VPValue *Def, VPTransformState &State) { |
| 2400 | IRBuilder<> &Builder = State.Builder; |
| 2401 | assert((isa<PHINode>(EntryVal) || isa<TruncInst>(EntryVal)) &&(static_cast <bool> ((isa<PHINode>(EntryVal) || isa <TruncInst>(EntryVal)) && "Expected either an induction phi-node or a truncate of it!" ) ? void (0) : __assert_fail ("(isa<PHINode>(EntryVal) || isa<TruncInst>(EntryVal)) && \"Expected either an induction phi-node or a truncate of it!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2402, __extension__ __PRETTY_FUNCTION__)) |
| 2402 | "Expected either an induction phi-node or a truncate of it!")(static_cast <bool> ((isa<PHINode>(EntryVal) || isa <TruncInst>(EntryVal)) && "Expected either an induction phi-node or a truncate of it!" ) ? void (0) : __assert_fail ("(isa<PHINode>(EntryVal) || isa<TruncInst>(EntryVal)) && \"Expected either an induction phi-node or a truncate of it!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2402, __extension__ __PRETTY_FUNCTION__)); |
| 2403 | |
| 2404 | // Construct the initial value of the vector IV in the vector loop preheader |
| 2405 | auto CurrIP = Builder.saveIP(); |
| 2406 | Builder.SetInsertPoint(LoopVectorPreHeader->getTerminator()); |
| 2407 | if (isa<TruncInst>(EntryVal)) { |
| 2408 | assert(Start->getType()->isIntegerTy() &&(static_cast <bool> (Start->getType()->isIntegerTy () && "Truncation requires an integer type") ? void ( 0) : __assert_fail ("Start->getType()->isIntegerTy() && \"Truncation requires an integer type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2409, __extension__ __PRETTY_FUNCTION__)) |
| 2409 | "Truncation requires an integer type")(static_cast <bool> (Start->getType()->isIntegerTy () && "Truncation requires an integer type") ? void ( 0) : __assert_fail ("Start->getType()->isIntegerTy() && \"Truncation requires an integer type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2409, __extension__ __PRETTY_FUNCTION__)); |
| 2410 | auto *TruncType = cast<IntegerType>(EntryVal->getType()); |
| 2411 | Step = Builder.CreateTrunc(Step, TruncType); |
| 2412 | Start = Builder.CreateCast(Instruction::Trunc, Start, TruncType); |
| 2413 | } |
| 2414 | |
| 2415 | Value *Zero = getSignedIntOrFpConstant(Start->getType(), 0); |
| 2416 | Value *SplatStart = Builder.CreateVectorSplat(State.VF, Start); |
| 2417 | Value *SteppedStart = getStepVector( |
| 2418 | SplatStart, Zero, Step, II.getInductionOpcode(), State.VF, State.Builder); |
| 2419 | |
| 2420 | // We create vector phi nodes for both integer and floating-point induction |
| 2421 | // variables. Here, we determine the kind of arithmetic we will perform. |
| 2422 | Instruction::BinaryOps AddOp; |
| 2423 | Instruction::BinaryOps MulOp; |
| 2424 | if (Step->getType()->isIntegerTy()) { |
| 2425 | AddOp = Instruction::Add; |
| 2426 | MulOp = Instruction::Mul; |
| 2427 | } else { |
| 2428 | AddOp = II.getInductionOpcode(); |
| 2429 | MulOp = Instruction::FMul; |
| 2430 | } |
| 2431 | |
| 2432 | // Multiply the vectorization factor by the step using integer or |
| 2433 | // floating-point arithmetic as appropriate. |
| 2434 | Type *StepType = Step->getType(); |
| 2435 | Value *RuntimeVF; |
| 2436 | if (Step->getType()->isFloatingPointTy()) |
| 2437 | RuntimeVF = getRuntimeVFAsFloat(Builder, StepType, State.VF); |
| 2438 | else |
| 2439 | RuntimeVF = getRuntimeVF(Builder, StepType, State.VF); |
| 2440 | Value *Mul = Builder.CreateBinOp(MulOp, Step, RuntimeVF); |
| 2441 | |
| 2442 | // Create a vector splat to use in the induction update. |
| 2443 | // |
| 2444 | // FIXME: If the step is non-constant, we create the vector splat with |
| 2445 | // IRBuilder. IRBuilder can constant-fold the multiply, but it doesn't |
| 2446 | // handle a constant vector splat. |
| 2447 | Value *SplatVF = isa<Constant>(Mul) |
| 2448 | ? ConstantVector::getSplat(State.VF, cast<Constant>(Mul)) |
| 2449 | : Builder.CreateVectorSplat(State.VF, Mul); |
| 2450 | Builder.restoreIP(CurrIP); |
| 2451 | |
| 2452 | // We may need to add the step a number of times, depending on the unroll |
| 2453 | // factor. The last of those goes into the PHI. |
| 2454 | PHINode *VecInd = PHINode::Create(SteppedStart->getType(), 2, "vec.ind", |
| 2455 | &*LoopVectorBody->getFirstInsertionPt()); |
| 2456 | VecInd->setDebugLoc(EntryVal->getDebugLoc()); |
| 2457 | Instruction *LastInduction = VecInd; |
| 2458 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 2459 | State.set(Def, LastInduction, Part); |
| 2460 | |
| 2461 | if (isa<TruncInst>(EntryVal)) |
| 2462 | addMetadata(LastInduction, EntryVal); |
| 2463 | |
| 2464 | LastInduction = cast<Instruction>( |
| 2465 | Builder.CreateBinOp(AddOp, LastInduction, SplatVF, "step.add")); |
| 2466 | LastInduction->setDebugLoc(EntryVal->getDebugLoc()); |
| 2467 | } |
| 2468 | |
| 2469 | // Move the last step to the end of the latch block. This ensures consistent |
| 2470 | // placement of all induction updates. |
| 2471 | auto *LoopVectorLatch = LI->getLoopFor(LoopVectorBody)->getLoopLatch(); |
| 2472 | auto *Br = cast<BranchInst>(LoopVectorLatch->getTerminator()); |
| 2473 | LastInduction->moveBefore(Br); |
| 2474 | LastInduction->setName("vec.ind.next"); |
| 2475 | |
| 2476 | VecInd->addIncoming(SteppedStart, LoopVectorPreHeader); |
| 2477 | VecInd->addIncoming(LastInduction, LoopVectorLatch); |
| 2478 | } |
| 2479 | |
| 2480 | void InnerLoopVectorizer::widenIntOrFpInduction( |
| 2481 | PHINode *IV, VPWidenIntOrFpInductionRecipe *Def, VPTransformState &State, |
| 2482 | Value *CanonicalIV) { |
| 2483 | Value *Start = Def->getStartValue()->getLiveInIRValue(); |
| 2484 | const InductionDescriptor &ID = Def->getInductionDescriptor(); |
| 2485 | TruncInst *Trunc = Def->getTruncInst(); |
| 2486 | IRBuilder<> &Builder = State.Builder; |
| 2487 | assert(IV->getType() == ID.getStartValue()->getType() && "Types must match")(static_cast <bool> (IV->getType() == ID.getStartValue ()->getType() && "Types must match") ? void (0) : __assert_fail ("IV->getType() == ID.getStartValue()->getType() && \"Types must match\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2487, __extension__ __PRETTY_FUNCTION__)); |
| 2488 | assert(!State.VF.isZero() && "VF must be non-zero")(static_cast <bool> (!State.VF.isZero() && "VF must be non-zero" ) ? void (0) : __assert_fail ("!State.VF.isZero() && \"VF must be non-zero\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2488, __extension__ __PRETTY_FUNCTION__)); |
| 2489 | |
| 2490 | // The value from the original loop to which we are mapping the new induction |
| 2491 | // variable. |
| 2492 | Instruction *EntryVal = Trunc ? cast<Instruction>(Trunc) : IV; |
| 2493 | |
| 2494 | auto &DL = EntryVal->getModule()->getDataLayout(); |
| 2495 | |
| 2496 | // Generate code for the induction step. Note that induction steps are |
| 2497 | // required to be loop-invariant |
| 2498 | auto CreateStepValue = [&](const SCEV *Step) -> Value * { |
| 2499 | assert(PSE.getSE()->isLoopInvariant(Step, OrigLoop) &&(static_cast <bool> (PSE.getSE()->isLoopInvariant(Step , OrigLoop) && "Induction step should be loop invariant" ) ? void (0) : __assert_fail ("PSE.getSE()->isLoopInvariant(Step, OrigLoop) && \"Induction step should be loop invariant\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2500, __extension__ __PRETTY_FUNCTION__)) |
| 2500 | "Induction step should be loop invariant")(static_cast <bool> (PSE.getSE()->isLoopInvariant(Step , OrigLoop) && "Induction step should be loop invariant" ) ? void (0) : __assert_fail ("PSE.getSE()->isLoopInvariant(Step, OrigLoop) && \"Induction step should be loop invariant\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2500, __extension__ __PRETTY_FUNCTION__)); |
| 2501 | if (PSE.getSE()->isSCEVable(IV->getType())) { |
| 2502 | SCEVExpander Exp(*PSE.getSE(), DL, "induction"); |
| 2503 | return Exp.expandCodeFor(Step, Step->getType(), |
| 2504 | State.CFG.VectorPreHeader->getTerminator()); |
| 2505 | } |
| 2506 | return cast<SCEVUnknown>(Step)->getValue(); |
| 2507 | }; |
| 2508 | |
| 2509 | // The scalar value to broadcast. This is derived from the canonical |
| 2510 | // induction variable. If a truncation type is given, truncate the canonical |
| 2511 | // induction variable and step. Otherwise, derive these values from the |
| 2512 | // induction descriptor. |
| 2513 | auto CreateScalarIV = [&](Value *&Step) -> Value * { |
| 2514 | Value *ScalarIV = CanonicalIV; |
| 2515 | Type *NeededType = IV->getType(); |
| 2516 | if (!Def->isCanonical() || ScalarIV->getType() != NeededType) { |
| 2517 | ScalarIV = |
| 2518 | NeededType->isIntegerTy() |
| 2519 | ? Builder.CreateSExtOrTrunc(ScalarIV, NeededType) |
| 2520 | : Builder.CreateCast(Instruction::SIToFP, ScalarIV, NeededType); |
| 2521 | ScalarIV = emitTransformedIndex(Builder, ScalarIV, PSE.getSE(), DL, ID, |
| 2522 | State.CFG.PrevBB); |
| 2523 | ScalarIV->setName("offset.idx"); |
| 2524 | } |
| 2525 | if (Trunc) { |
| 2526 | auto *TruncType = cast<IntegerType>(Trunc->getType()); |
| 2527 | assert(Step->getType()->isIntegerTy() &&(static_cast <bool> (Step->getType()->isIntegerTy () && "Truncation requires an integer step") ? void ( 0) : __assert_fail ("Step->getType()->isIntegerTy() && \"Truncation requires an integer step\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2528, __extension__ __PRETTY_FUNCTION__)) |
| 2528 | "Truncation requires an integer step")(static_cast <bool> (Step->getType()->isIntegerTy () && "Truncation requires an integer step") ? void ( 0) : __assert_fail ("Step->getType()->isIntegerTy() && \"Truncation requires an integer step\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2528, __extension__ __PRETTY_FUNCTION__)); |
| 2529 | ScalarIV = Builder.CreateTrunc(ScalarIV, TruncType); |
| 2530 | Step = Builder.CreateTrunc(Step, TruncType); |
| 2531 | } |
| 2532 | return ScalarIV; |
| 2533 | }; |
| 2534 | |
| 2535 | // Fast-math-flags propagate from the original induction instruction. |
| 2536 | IRBuilder<>::FastMathFlagGuard FMFG(Builder); |
| 2537 | if (ID.getInductionBinOp() && isa<FPMathOperator>(ID.getInductionBinOp())) |
| 2538 | Builder.setFastMathFlags(ID.getInductionBinOp()->getFastMathFlags()); |
| 2539 | |
| 2540 | // Now do the actual transformations, and start with creating the step value. |
| 2541 | Value *Step = CreateStepValue(ID.getStep()); |
| 2542 | if (State.VF.isScalar()) { |
| 2543 | Value *ScalarIV = CreateScalarIV(Step); |
| 2544 | Type *ScalarTy = IntegerType::get(ScalarIV->getContext(), |
| 2545 | Step->getType()->getScalarSizeInBits()); |
| 2546 | |
| 2547 | Instruction::BinaryOps IncOp = ID.getInductionOpcode(); |
| 2548 | if (IncOp == Instruction::BinaryOpsEnd) |
| 2549 | IncOp = Instruction::Add; |
| 2550 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 2551 | Value *StartIdx = ConstantInt::get(ScalarTy, Part); |
| 2552 | Instruction::BinaryOps MulOp = Instruction::Mul; |
| 2553 | if (Step->getType()->isFloatingPointTy()) { |
| 2554 | StartIdx = Builder.CreateUIToFP(StartIdx, Step->getType()); |
| 2555 | MulOp = Instruction::FMul; |
| 2556 | } |
| 2557 | |
| 2558 | Value *Mul = Builder.CreateBinOp(MulOp, StartIdx, Step); |
| 2559 | Value *EntryPart = Builder.CreateBinOp(IncOp, ScalarIV, Mul, "induction"); |
| 2560 | State.set(Def, EntryPart, Part); |
| 2561 | if (Trunc) { |
| 2562 | assert(!Step->getType()->isFloatingPointTy() &&(static_cast <bool> (!Step->getType()->isFloatingPointTy () && "fp inductions shouldn't be truncated") ? void ( 0) : __assert_fail ("!Step->getType()->isFloatingPointTy() && \"fp inductions shouldn't be truncated\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2563, __extension__ __PRETTY_FUNCTION__)) |
| 2563 | "fp inductions shouldn't be truncated")(static_cast <bool> (!Step->getType()->isFloatingPointTy () && "fp inductions shouldn't be truncated") ? void ( 0) : __assert_fail ("!Step->getType()->isFloatingPointTy() && \"fp inductions shouldn't be truncated\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2563, __extension__ __PRETTY_FUNCTION__)); |
| 2564 | addMetadata(EntryPart, Trunc); |
| 2565 | } |
| 2566 | } |
| 2567 | return; |
| 2568 | } |
| 2569 | |
| 2570 | // Create a new independent vector induction variable, if one is needed. |
| 2571 | if (Def->needsVectorIV()) |
| 2572 | createVectorIntOrFpInductionPHI(ID, Step, Start, EntryVal, Def, State); |
| 2573 | |
| 2574 | if (Def->needsScalarIV()) { |
| 2575 | // Create scalar steps that can be used by instructions we will later |
| 2576 | // scalarize. Note that the addition of the scalar steps will not increase |
| 2577 | // the number of instructions in the loop in the common case prior to |
| 2578 | // InstCombine. We will be trading one vector extract for each scalar step. |
| 2579 | Value *ScalarIV = CreateScalarIV(Step); |
| 2580 | buildScalarSteps(ScalarIV, Step, EntryVal, ID, Def, State); |
| 2581 | } |
| 2582 | } |
| 2583 | |
| 2584 | void InnerLoopVectorizer::buildScalarSteps(Value *ScalarIV, Value *Step, |
| 2585 | Instruction *EntryVal, |
| 2586 | const InductionDescriptor &ID, |
| 2587 | VPValue *Def, |
| 2588 | VPTransformState &State) { |
| 2589 | IRBuilder<> &Builder = State.Builder; |
| 2590 | // We shouldn't have to build scalar steps if we aren't vectorizing. |
| 2591 | assert(State.VF.isVector() && "VF should be greater than one")(static_cast <bool> (State.VF.isVector() && "VF should be greater than one" ) ? void (0) : __assert_fail ("State.VF.isVector() && \"VF should be greater than one\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2591, __extension__ __PRETTY_FUNCTION__)); |
| 2592 | // Get the value type and ensure it and the step have the same integer type. |
| 2593 | Type *ScalarIVTy = ScalarIV->getType()->getScalarType(); |
| 2594 | assert(ScalarIVTy == Step->getType() &&(static_cast <bool> (ScalarIVTy == Step->getType() && "Val and Step should have the same type") ? void (0) : __assert_fail ("ScalarIVTy == Step->getType() && \"Val and Step should have the same type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2595, __extension__ __PRETTY_FUNCTION__)) |
| 2595 | "Val and Step should have the same type")(static_cast <bool> (ScalarIVTy == Step->getType() && "Val and Step should have the same type") ? void (0) : __assert_fail ("ScalarIVTy == Step->getType() && \"Val and Step should have the same type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2595, __extension__ __PRETTY_FUNCTION__)); |
| 2596 | |
| 2597 | // We build scalar steps for both integer and floating-point induction |
| 2598 | // variables. Here, we determine the kind of arithmetic we will perform. |
| 2599 | Instruction::BinaryOps AddOp; |
| 2600 | Instruction::BinaryOps MulOp; |
| 2601 | if (ScalarIVTy->isIntegerTy()) { |
| 2602 | AddOp = Instruction::Add; |
| 2603 | MulOp = Instruction::Mul; |
| 2604 | } else { |
| 2605 | AddOp = ID.getInductionOpcode(); |
| 2606 | MulOp = Instruction::FMul; |
| 2607 | } |
| 2608 | |
| 2609 | // Determine the number of scalars we need to generate for each unroll |
| 2610 | // iteration. |
| 2611 | bool FirstLaneOnly = vputils::onlyFirstLaneUsed(Def); |
| 2612 | unsigned Lanes = FirstLaneOnly ? 1 : State.VF.getKnownMinValue(); |
| 2613 | // Compute the scalar steps and save the results in State. |
| 2614 | Type *IntStepTy = IntegerType::get(ScalarIVTy->getContext(), |
| 2615 | ScalarIVTy->getScalarSizeInBits()); |
| 2616 | Type *VecIVTy = nullptr; |
| 2617 | Value *UnitStepVec = nullptr, *SplatStep = nullptr, *SplatIV = nullptr; |
| 2618 | if (!FirstLaneOnly && State.VF.isScalable()) { |
| 2619 | VecIVTy = VectorType::get(ScalarIVTy, State.VF); |
| 2620 | UnitStepVec = |
| 2621 | Builder.CreateStepVector(VectorType::get(IntStepTy, State.VF)); |
| 2622 | SplatStep = Builder.CreateVectorSplat(State.VF, Step); |
| 2623 | SplatIV = Builder.CreateVectorSplat(State.VF, ScalarIV); |
| 2624 | } |
| 2625 | |
| 2626 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 2627 | Value *StartIdx0 = createStepForVF(Builder, IntStepTy, State.VF, Part); |
| 2628 | |
| 2629 | if (!FirstLaneOnly && State.VF.isScalable()) { |
| 2630 | auto *SplatStartIdx = Builder.CreateVectorSplat(State.VF, StartIdx0); |
| 2631 | auto *InitVec = Builder.CreateAdd(SplatStartIdx, UnitStepVec); |
| 2632 | if (ScalarIVTy->isFloatingPointTy()) |
| 2633 | InitVec = Builder.CreateSIToFP(InitVec, VecIVTy); |
| 2634 | auto *Mul = Builder.CreateBinOp(MulOp, InitVec, SplatStep); |
| 2635 | auto *Add = Builder.CreateBinOp(AddOp, SplatIV, Mul); |
| 2636 | State.set(Def, Add, Part); |
| 2637 | // It's useful to record the lane values too for the known minimum number |
| 2638 | // of elements so we do those below. This improves the code quality when |
| 2639 | // trying to extract the first element, for example. |
| 2640 | } |
| 2641 | |
| 2642 | if (ScalarIVTy->isFloatingPointTy()) |
| 2643 | StartIdx0 = Builder.CreateSIToFP(StartIdx0, ScalarIVTy); |
| 2644 | |
| 2645 | for (unsigned Lane = 0; Lane < Lanes; ++Lane) { |
| 2646 | Value *StartIdx = Builder.CreateBinOp( |
| 2647 | AddOp, StartIdx0, getSignedIntOrFpConstant(ScalarIVTy, Lane)); |
| 2648 | // The step returned by `createStepForVF` is a runtime-evaluated value |
| 2649 | // when VF is scalable. Otherwise, it should be folded into a Constant. |
| 2650 | assert((State.VF.isScalable() || isa<Constant>(StartIdx)) &&(static_cast <bool> ((State.VF.isScalable() || isa<Constant >(StartIdx)) && "Expected StartIdx to be folded to a constant when VF is not " "scalable") ? void (0) : __assert_fail ("(State.VF.isScalable() || isa<Constant>(StartIdx)) && \"Expected StartIdx to be folded to a constant when VF is not \" \"scalable\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2652, __extension__ __PRETTY_FUNCTION__)) |
| 2651 | "Expected StartIdx to be folded to a constant when VF is not "(static_cast <bool> ((State.VF.isScalable() || isa<Constant >(StartIdx)) && "Expected StartIdx to be folded to a constant when VF is not " "scalable") ? void (0) : __assert_fail ("(State.VF.isScalable() || isa<Constant>(StartIdx)) && \"Expected StartIdx to be folded to a constant when VF is not \" \"scalable\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2652, __extension__ __PRETTY_FUNCTION__)) |
| 2652 | "scalable")(static_cast <bool> ((State.VF.isScalable() || isa<Constant >(StartIdx)) && "Expected StartIdx to be folded to a constant when VF is not " "scalable") ? void (0) : __assert_fail ("(State.VF.isScalable() || isa<Constant>(StartIdx)) && \"Expected StartIdx to be folded to a constant when VF is not \" \"scalable\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2652, __extension__ __PRETTY_FUNCTION__)); |
| 2653 | auto *Mul = Builder.CreateBinOp(MulOp, StartIdx, Step); |
| 2654 | auto *Add = Builder.CreateBinOp(AddOp, ScalarIV, Mul); |
| 2655 | State.set(Def, Add, VPIteration(Part, Lane)); |
| 2656 | } |
| 2657 | } |
| 2658 | } |
| 2659 | |
| 2660 | void InnerLoopVectorizer::packScalarIntoVectorValue(VPValue *Def, |
| 2661 | const VPIteration &Instance, |
| 2662 | VPTransformState &State) { |
| 2663 | Value *ScalarInst = State.get(Def, Instance); |
| 2664 | Value *VectorValue = State.get(Def, Instance.Part); |
| 2665 | VectorValue = Builder.CreateInsertElement( |
| 2666 | VectorValue, ScalarInst, |
| 2667 | Instance.Lane.getAsRuntimeExpr(State.Builder, VF)); |
| 2668 | State.set(Def, VectorValue, Instance.Part); |
| 2669 | } |
| 2670 | |
| 2671 | // Return whether we allow using masked interleave-groups (for dealing with |
| 2672 | // strided loads/stores that reside in predicated blocks, or for dealing |
| 2673 | // with gaps). |
| 2674 | static bool useMaskedInterleavedAccesses(const TargetTransformInfo &TTI) { |
| 2675 | // If an override option has been passed in for interleaved accesses, use it. |
| 2676 | if (EnableMaskedInterleavedMemAccesses.getNumOccurrences() > 0) |
| 2677 | return EnableMaskedInterleavedMemAccesses; |
| 2678 | |
| 2679 | return TTI.enableMaskedInterleavedAccessVectorization(); |
| 2680 | } |
| 2681 | |
| 2682 | // Try to vectorize the interleave group that \p Instr belongs to. |
| 2683 | // |
| 2684 | // E.g. Translate following interleaved load group (factor = 3): |
| 2685 | // for (i = 0; i < N; i+=3) { |
| 2686 | // R = Pic[i]; // Member of index 0 |
| 2687 | // G = Pic[i+1]; // Member of index 1 |
| 2688 | // B = Pic[i+2]; // Member of index 2 |
| 2689 | // ... // do something to R, G, B |
| 2690 | // } |
| 2691 | // To: |
| 2692 | // %wide.vec = load <12 x i32> ; Read 4 tuples of R,G,B |
| 2693 | // %R.vec = shuffle %wide.vec, poison, <0, 3, 6, 9> ; R elements |
| 2694 | // %G.vec = shuffle %wide.vec, poison, <1, 4, 7, 10> ; G elements |
| 2695 | // %B.vec = shuffle %wide.vec, poison, <2, 5, 8, 11> ; B elements |
| 2696 | // |
| 2697 | // Or translate following interleaved store group (factor = 3): |
| 2698 | // for (i = 0; i < N; i+=3) { |
| 2699 | // ... do something to R, G, B |
| 2700 | // Pic[i] = R; // Member of index 0 |
| 2701 | // Pic[i+1] = G; // Member of index 1 |
| 2702 | // Pic[i+2] = B; // Member of index 2 |
| 2703 | // } |
| 2704 | // To: |
| 2705 | // %R_G.vec = shuffle %R.vec, %G.vec, <0, 1, 2, ..., 7> |
| 2706 | // %B_U.vec = shuffle %B.vec, poison, <0, 1, 2, 3, u, u, u, u> |
| 2707 | // %interleaved.vec = shuffle %R_G.vec, %B_U.vec, |
| 2708 | // <0, 4, 8, 1, 5, 9, 2, 6, 10, 3, 7, 11> ; Interleave R,G,B elements |
| 2709 | // store <12 x i32> %interleaved.vec ; Write 4 tuples of R,G,B |
| 2710 | void InnerLoopVectorizer::vectorizeInterleaveGroup( |
| 2711 | const InterleaveGroup<Instruction> *Group, ArrayRef<VPValue *> VPDefs, |
| 2712 | VPTransformState &State, VPValue *Addr, ArrayRef<VPValue *> StoredValues, |
| 2713 | VPValue *BlockInMask) { |
| 2714 | Instruction *Instr = Group->getInsertPos(); |
| 2715 | const DataLayout &DL = Instr->getModule()->getDataLayout(); |
| 2716 | |
| 2717 | // Prepare for the vector type of the interleaved load/store. |
| 2718 | Type *ScalarTy = getLoadStoreType(Instr); |
| 2719 | unsigned InterleaveFactor = Group->getFactor(); |
| 2720 | assert(!VF.isScalable() && "scalable vectors not yet supported.")(static_cast <bool> (!VF.isScalable() && "scalable vectors not yet supported." ) ? void (0) : __assert_fail ("!VF.isScalable() && \"scalable vectors not yet supported.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2720, __extension__ __PRETTY_FUNCTION__)); |
| 2721 | auto *VecTy = VectorType::get(ScalarTy, VF * InterleaveFactor); |
| 2722 | |
| 2723 | // Prepare for the new pointers. |
| 2724 | SmallVector<Value *, 2> AddrParts; |
| 2725 | unsigned Index = Group->getIndex(Instr); |
| 2726 | |
| 2727 | // TODO: extend the masked interleaved-group support to reversed access. |
| 2728 | assert((!BlockInMask || !Group->isReverse()) &&(static_cast <bool> ((!BlockInMask || !Group->isReverse ()) && "Reversed masked interleave-group not supported." ) ? void (0) : __assert_fail ("(!BlockInMask || !Group->isReverse()) && \"Reversed masked interleave-group not supported.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2729, __extension__ __PRETTY_FUNCTION__)) |
| 2729 | "Reversed masked interleave-group not supported.")(static_cast <bool> ((!BlockInMask || !Group->isReverse ()) && "Reversed masked interleave-group not supported." ) ? void (0) : __assert_fail ("(!BlockInMask || !Group->isReverse()) && \"Reversed masked interleave-group not supported.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2729, __extension__ __PRETTY_FUNCTION__)); |
| 2730 | |
| 2731 | // If the group is reverse, adjust the index to refer to the last vector lane |
| 2732 | // instead of the first. We adjust the index from the first vector lane, |
| 2733 | // rather than directly getting the pointer for lane VF - 1, because the |
| 2734 | // pointer operand of the interleaved access is supposed to be uniform. For |
| 2735 | // uniform instructions, we're only required to generate a value for the |
| 2736 | // first vector lane in each unroll iteration. |
| 2737 | if (Group->isReverse()) |
| 2738 | Index += (VF.getKnownMinValue() - 1) * Group->getFactor(); |
| 2739 | |
| 2740 | for (unsigned Part = 0; Part < UF; Part++) { |
| 2741 | Value *AddrPart = State.get(Addr, VPIteration(Part, 0)); |
| 2742 | setDebugLocFromInst(AddrPart); |
| 2743 | |
| 2744 | // Notice current instruction could be any index. Need to adjust the address |
| 2745 | // to the member of index 0. |
| 2746 | // |
| 2747 | // E.g. a = A[i+1]; // Member of index 1 (Current instruction) |
| 2748 | // b = A[i]; // Member of index 0 |
| 2749 | // Current pointer is pointed to A[i+1], adjust it to A[i]. |
| 2750 | // |
| 2751 | // E.g. A[i+1] = a; // Member of index 1 |
| 2752 | // A[i] = b; // Member of index 0 |
| 2753 | // A[i+2] = c; // Member of index 2 (Current instruction) |
| 2754 | // Current pointer is pointed to A[i+2], adjust it to A[i]. |
| 2755 | |
| 2756 | bool InBounds = false; |
| 2757 | if (auto *gep = dyn_cast<GetElementPtrInst>(AddrPart->stripPointerCasts())) |
| 2758 | InBounds = gep->isInBounds(); |
| 2759 | AddrPart = Builder.CreateGEP(ScalarTy, AddrPart, Builder.getInt32(-Index)); |
| 2760 | cast<GetElementPtrInst>(AddrPart)->setIsInBounds(InBounds); |
| 2761 | |
| 2762 | // Cast to the vector pointer type. |
| 2763 | unsigned AddressSpace = AddrPart->getType()->getPointerAddressSpace(); |
| 2764 | Type *PtrTy = VecTy->getPointerTo(AddressSpace); |
| 2765 | AddrParts.push_back(Builder.CreateBitCast(AddrPart, PtrTy)); |
| 2766 | } |
| 2767 | |
| 2768 | setDebugLocFromInst(Instr); |
| 2769 | Value *PoisonVec = PoisonValue::get(VecTy); |
| 2770 | |
| 2771 | Value *MaskForGaps = nullptr; |
| 2772 | if (Group->requiresScalarEpilogue() && !Cost->isScalarEpilogueAllowed()) { |
| 2773 | MaskForGaps = createBitMaskForGaps(Builder, VF.getKnownMinValue(), *Group); |
| 2774 | assert(MaskForGaps && "Mask for Gaps is required but it is null")(static_cast <bool> (MaskForGaps && "Mask for Gaps is required but it is null" ) ? void (0) : __assert_fail ("MaskForGaps && \"Mask for Gaps is required but it is null\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2774, __extension__ __PRETTY_FUNCTION__)); |
| 2775 | } |
| 2776 | |
| 2777 | // Vectorize the interleaved load group. |
| 2778 | if (isa<LoadInst>(Instr)) { |
| 2779 | // For each unroll part, create a wide load for the group. |
| 2780 | SmallVector<Value *, 2> NewLoads; |
| 2781 | for (unsigned Part = 0; Part < UF; Part++) { |
| 2782 | Instruction *NewLoad; |
| 2783 | if (BlockInMask || MaskForGaps) { |
| 2784 | assert(useMaskedInterleavedAccesses(*TTI) &&(static_cast <bool> (useMaskedInterleavedAccesses(*TTI) && "masked interleaved groups are not allowed.") ? void (0) : __assert_fail ("useMaskedInterleavedAccesses(*TTI) && \"masked interleaved groups are not allowed.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2785, __extension__ __PRETTY_FUNCTION__)) |
| 2785 | "masked interleaved groups are not allowed.")(static_cast <bool> (useMaskedInterleavedAccesses(*TTI) && "masked interleaved groups are not allowed.") ? void (0) : __assert_fail ("useMaskedInterleavedAccesses(*TTI) && \"masked interleaved groups are not allowed.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2785, __extension__ __PRETTY_FUNCTION__)); |
| 2786 | Value *GroupMask = MaskForGaps; |
| 2787 | if (BlockInMask) { |
| 2788 | Value *BlockInMaskPart = State.get(BlockInMask, Part); |
| 2789 | Value *ShuffledMask = Builder.CreateShuffleVector( |
| 2790 | BlockInMaskPart, |
| 2791 | createReplicatedMask(InterleaveFactor, VF.getKnownMinValue()), |
| 2792 | "interleaved.mask"); |
| 2793 | GroupMask = MaskForGaps |
| 2794 | ? Builder.CreateBinOp(Instruction::And, ShuffledMask, |
| 2795 | MaskForGaps) |
| 2796 | : ShuffledMask; |
| 2797 | } |
| 2798 | NewLoad = |
| 2799 | Builder.CreateMaskedLoad(VecTy, AddrParts[Part], Group->getAlign(), |
| 2800 | GroupMask, PoisonVec, "wide.masked.vec"); |
| 2801 | } |
| 2802 | else |
| 2803 | NewLoad = Builder.CreateAlignedLoad(VecTy, AddrParts[Part], |
| 2804 | Group->getAlign(), "wide.vec"); |
| 2805 | Group->addMetadata(NewLoad); |
| 2806 | NewLoads.push_back(NewLoad); |
| 2807 | } |
| 2808 | |
| 2809 | // For each member in the group, shuffle out the appropriate data from the |
| 2810 | // wide loads. |
| 2811 | unsigned J = 0; |
| 2812 | for (unsigned I = 0; I < InterleaveFactor; ++I) { |
| 2813 | Instruction *Member = Group->getMember(I); |
| 2814 | |
| 2815 | // Skip the gaps in the group. |
| 2816 | if (!Member) |
| 2817 | continue; |
| 2818 | |
| 2819 | auto StrideMask = |
| 2820 | createStrideMask(I, InterleaveFactor, VF.getKnownMinValue()); |
| 2821 | for (unsigned Part = 0; Part < UF; Part++) { |
| 2822 | Value *StridedVec = Builder.CreateShuffleVector( |
| 2823 | NewLoads[Part], StrideMask, "strided.vec"); |
| 2824 | |
| 2825 | // If this member has different type, cast the result type. |
| 2826 | if (Member->getType() != ScalarTy) { |
| 2827 | assert(!VF.isScalable() && "VF is assumed to be non scalable.")(static_cast <bool> (!VF.isScalable() && "VF is assumed to be non scalable." ) ? void (0) : __assert_fail ("!VF.isScalable() && \"VF is assumed to be non scalable.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2827, __extension__ __PRETTY_FUNCTION__)); |
| 2828 | VectorType *OtherVTy = VectorType::get(Member->getType(), VF); |
| 2829 | StridedVec = createBitOrPointerCast(StridedVec, OtherVTy, DL); |
| 2830 | } |
| 2831 | |
| 2832 | if (Group->isReverse()) |
| 2833 | StridedVec = Builder.CreateVectorReverse(StridedVec, "reverse"); |
| 2834 | |
| 2835 | State.set(VPDefs[J], StridedVec, Part); |
| 2836 | } |
| 2837 | ++J; |
| 2838 | } |
| 2839 | return; |
| 2840 | } |
| 2841 | |
| 2842 | // The sub vector type for current instruction. |
| 2843 | auto *SubVT = VectorType::get(ScalarTy, VF); |
| 2844 | |
| 2845 | // Vectorize the interleaved store group. |
| 2846 | MaskForGaps = createBitMaskForGaps(Builder, VF.getKnownMinValue(), *Group); |
| 2847 | assert((!MaskForGaps || useMaskedInterleavedAccesses(*TTI)) &&(static_cast <bool> ((!MaskForGaps || useMaskedInterleavedAccesses (*TTI)) && "masked interleaved groups are not allowed." ) ? void (0) : __assert_fail ("(!MaskForGaps || useMaskedInterleavedAccesses(*TTI)) && \"masked interleaved groups are not allowed.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2848, __extension__ __PRETTY_FUNCTION__)) |
| 2848 | "masked interleaved groups are not allowed.")(static_cast <bool> ((!MaskForGaps || useMaskedInterleavedAccesses (*TTI)) && "masked interleaved groups are not allowed." ) ? void (0) : __assert_fail ("(!MaskForGaps || useMaskedInterleavedAccesses(*TTI)) && \"masked interleaved groups are not allowed.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2848, __extension__ __PRETTY_FUNCTION__)); |
| 2849 | assert((!MaskForGaps || !VF.isScalable()) &&(static_cast <bool> ((!MaskForGaps || !VF.isScalable()) && "masking gaps for scalable vectors is not yet supported." ) ? void (0) : __assert_fail ("(!MaskForGaps || !VF.isScalable()) && \"masking gaps for scalable vectors is not yet supported.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2850, __extension__ __PRETTY_FUNCTION__)) |
| 2850 | "masking gaps for scalable vectors is not yet supported.")(static_cast <bool> ((!MaskForGaps || !VF.isScalable()) && "masking gaps for scalable vectors is not yet supported." ) ? void (0) : __assert_fail ("(!MaskForGaps || !VF.isScalable()) && \"masking gaps for scalable vectors is not yet supported.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2850, __extension__ __PRETTY_FUNCTION__)); |
| 2851 | for (unsigned Part = 0; Part < UF; Part++) { |
| 2852 | // Collect the stored vector from each member. |
| 2853 | SmallVector<Value *, 4> StoredVecs; |
| 2854 | for (unsigned i = 0; i < InterleaveFactor; i++) { |
| 2855 | assert((Group->getMember(i) || MaskForGaps) &&(static_cast <bool> ((Group->getMember(i) || MaskForGaps ) && "Fail to get a member from an interleaved store group" ) ? void (0) : __assert_fail ("(Group->getMember(i) || MaskForGaps) && \"Fail to get a member from an interleaved store group\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2856, __extension__ __PRETTY_FUNCTION__)) |
| 2856 | "Fail to get a member from an interleaved store group")(static_cast <bool> ((Group->getMember(i) || MaskForGaps ) && "Fail to get a member from an interleaved store group" ) ? void (0) : __assert_fail ("(Group->getMember(i) || MaskForGaps) && \"Fail to get a member from an interleaved store group\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2856, __extension__ __PRETTY_FUNCTION__)); |
| 2857 | Instruction *Member = Group->getMember(i); |
| 2858 | |
| 2859 | // Skip the gaps in the group. |
| 2860 | if (!Member) { |
| 2861 | Value *Undef = PoisonValue::get(SubVT); |
| 2862 | StoredVecs.push_back(Undef); |
| 2863 | continue; |
| 2864 | } |
| 2865 | |
| 2866 | Value *StoredVec = State.get(StoredValues[i], Part); |
| 2867 | |
| 2868 | if (Group->isReverse()) |
| 2869 | StoredVec = Builder.CreateVectorReverse(StoredVec, "reverse"); |
| 2870 | |
| 2871 | // If this member has different type, cast it to a unified type. |
| 2872 | |
| 2873 | if (StoredVec->getType() != SubVT) |
| 2874 | StoredVec = createBitOrPointerCast(StoredVec, SubVT, DL); |
| 2875 | |
| 2876 | StoredVecs.push_back(StoredVec); |
| 2877 | } |
| 2878 | |
| 2879 | // Concatenate all vectors into a wide vector. |
| 2880 | Value *WideVec = concatenateVectors(Builder, StoredVecs); |
| 2881 | |
| 2882 | // Interleave the elements in the wide vector. |
| 2883 | Value *IVec = Builder.CreateShuffleVector( |
| 2884 | WideVec, createInterleaveMask(VF.getKnownMinValue(), InterleaveFactor), |
| 2885 | "interleaved.vec"); |
| 2886 | |
| 2887 | Instruction *NewStoreInstr; |
| 2888 | if (BlockInMask || MaskForGaps) { |
| 2889 | Value *GroupMask = MaskForGaps; |
| 2890 | if (BlockInMask) { |
| 2891 | Value *BlockInMaskPart = State.get(BlockInMask, Part); |
| 2892 | Value *ShuffledMask = Builder.CreateShuffleVector( |
| 2893 | BlockInMaskPart, |
| 2894 | createReplicatedMask(InterleaveFactor, VF.getKnownMinValue()), |
| 2895 | "interleaved.mask"); |
| 2896 | GroupMask = MaskForGaps ? Builder.CreateBinOp(Instruction::And, |
| 2897 | ShuffledMask, MaskForGaps) |
| 2898 | : ShuffledMask; |
| 2899 | } |
| 2900 | NewStoreInstr = Builder.CreateMaskedStore(IVec, AddrParts[Part], |
| 2901 | Group->getAlign(), GroupMask); |
| 2902 | } else |
| 2903 | NewStoreInstr = |
| 2904 | Builder.CreateAlignedStore(IVec, AddrParts[Part], Group->getAlign()); |
| 2905 | |
| 2906 | Group->addMetadata(NewStoreInstr); |
| 2907 | } |
| 2908 | } |
| 2909 | |
| 2910 | void InnerLoopVectorizer::scalarizeInstruction(Instruction *Instr, |
| 2911 | VPReplicateRecipe *RepRecipe, |
| 2912 | const VPIteration &Instance, |
| 2913 | bool IfPredicateInstr, |
| 2914 | VPTransformState &State) { |
| 2915 | assert(!Instr->getType()->isAggregateType() && "Can't handle vectors")(static_cast <bool> (!Instr->getType()->isAggregateType () && "Can't handle vectors") ? void (0) : __assert_fail ("!Instr->getType()->isAggregateType() && \"Can't handle vectors\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2915, __extension__ __PRETTY_FUNCTION__)); |
| 2916 | |
| 2917 | // llvm.experimental.noalias.scope.decl intrinsics must only be duplicated for |
| 2918 | // the first lane and part. |
| 2919 | if (isa<NoAliasScopeDeclInst>(Instr)) |
| 2920 | if (!Instance.isFirstIteration()) |
| 2921 | return; |
| 2922 | |
| 2923 | setDebugLocFromInst(Instr); |
| 2924 | |
| 2925 | // Does this instruction return a value ? |
| 2926 | bool IsVoidRetTy = Instr->getType()->isVoidTy(); |
| 2927 | |
| 2928 | Instruction *Cloned = Instr->clone(); |
| 2929 | if (!IsVoidRetTy) |
| 2930 | Cloned->setName(Instr->getName() + ".cloned"); |
| 2931 | |
| 2932 | // If the scalarized instruction contributes to the address computation of a |
| 2933 | // widen masked load/store which was in a basic block that needed predication |
| 2934 | // and is not predicated after vectorization, we can't propagate |
| 2935 | // poison-generating flags (nuw/nsw, exact, inbounds, etc.). The scalarized |
| 2936 | // instruction could feed a poison value to the base address of the widen |
| 2937 | // load/store. |
| 2938 | if (State.MayGeneratePoisonRecipes.contains(RepRecipe)) |
| 2939 | Cloned->dropPoisonGeneratingFlags(); |
| 2940 | |
| 2941 | State.Builder.SetInsertPoint(Builder.GetInsertBlock(), |
| 2942 | Builder.GetInsertPoint()); |
| 2943 | // Replace the operands of the cloned instructions with their scalar |
| 2944 | // equivalents in the new loop. |
| 2945 | for (auto &I : enumerate(RepRecipe->operands())) { |
| 2946 | auto InputInstance = Instance; |
| 2947 | VPValue *Operand = I.value(); |
| 2948 | VPReplicateRecipe *OperandR = dyn_cast<VPReplicateRecipe>(Operand); |
| 2949 | if (OperandR && OperandR->isUniform()) |
| 2950 | InputInstance.Lane = VPLane::getFirstLane(); |
| 2951 | Cloned->setOperand(I.index(), State.get(Operand, InputInstance)); |
| 2952 | } |
| 2953 | addNewMetadata(Cloned, Instr); |
| 2954 | |
| 2955 | // Place the cloned scalar in the new loop. |
| 2956 | Builder.Insert(Cloned); |
| 2957 | |
| 2958 | State.set(RepRecipe, Cloned, Instance); |
| 2959 | |
| 2960 | // If we just cloned a new assumption, add it the assumption cache. |
| 2961 | if (auto *II = dyn_cast<AssumeInst>(Cloned)) |
| 2962 | AC->registerAssumption(II); |
| 2963 | |
| 2964 | // End if-block. |
| 2965 | if (IfPredicateInstr) |
| 2966 | PredicatedInstructions.push_back(Cloned); |
| 2967 | } |
| 2968 | |
| 2969 | void InnerLoopVectorizer::createHeaderBranch(Loop *L) { |
| 2970 | BasicBlock *Header = L->getHeader(); |
| 2971 | assert(!L->getLoopLatch() && "loop should not have a latch at this point")(static_cast <bool> (!L->getLoopLatch() && "loop should not have a latch at this point" ) ? void (0) : __assert_fail ("!L->getLoopLatch() && \"loop should not have a latch at this point\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2971, __extension__ __PRETTY_FUNCTION__)); |
| 2972 | |
| 2973 | IRBuilder<> B(Header->getTerminator()); |
| 2974 | Instruction *OldInst = |
| 2975 | getDebugLocFromInstOrOperands(Legal->getPrimaryInduction()); |
| 2976 | setDebugLocFromInst(OldInst, &B); |
| 2977 | |
| 2978 | // Connect the header to the exit and header blocks and replace the old |
| 2979 | // terminator. |
| 2980 | B.CreateCondBr(B.getTrue(), L->getUniqueExitBlock(), Header); |
| 2981 | |
| 2982 | // Now we have two terminators. Remove the old one from the block. |
| 2983 | Header->getTerminator()->eraseFromParent(); |
| 2984 | } |
| 2985 | |
| 2986 | Value *InnerLoopVectorizer::getOrCreateTripCount(Loop *L) { |
| 2987 | if (TripCount) |
| 2988 | return TripCount; |
| 2989 | |
| 2990 | assert(L && "Create Trip Count for null loop.")(static_cast <bool> (L && "Create Trip Count for null loop." ) ? void (0) : __assert_fail ("L && \"Create Trip Count for null loop.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2990, __extension__ __PRETTY_FUNCTION__)); |
| 2991 | IRBuilder<> Builder(L->getLoopPreheader()->getTerminator()); |
| 2992 | // Find the loop boundaries. |
| 2993 | ScalarEvolution *SE = PSE.getSE(); |
| 2994 | const SCEV *BackedgeTakenCount = PSE.getBackedgeTakenCount(); |
| 2995 | assert(!isa<SCEVCouldNotCompute>(BackedgeTakenCount) &&(static_cast <bool> (!isa<SCEVCouldNotCompute>(BackedgeTakenCount ) && "Invalid loop count") ? void (0) : __assert_fail ("!isa<SCEVCouldNotCompute>(BackedgeTakenCount) && \"Invalid loop count\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2996, __extension__ __PRETTY_FUNCTION__)) |
| 2996 | "Invalid loop count")(static_cast <bool> (!isa<SCEVCouldNotCompute>(BackedgeTakenCount ) && "Invalid loop count") ? void (0) : __assert_fail ("!isa<SCEVCouldNotCompute>(BackedgeTakenCount) && \"Invalid loop count\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2996, __extension__ __PRETTY_FUNCTION__)); |
| 2997 | |
| 2998 | Type *IdxTy = Legal->getWidestInductionType(); |
| 2999 | assert(IdxTy && "No type for induction")(static_cast <bool> (IdxTy && "No type for induction" ) ? void (0) : __assert_fail ("IdxTy && \"No type for induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 2999, __extension__ __PRETTY_FUNCTION__)); |
| 3000 | |
| 3001 | // The exit count might have the type of i64 while the phi is i32. This can |
| 3002 | // happen if we have an induction variable that is sign extended before the |
| 3003 | // compare. The only way that we get a backedge taken count is that the |
| 3004 | // induction variable was signed and as such will not overflow. In such a case |
| 3005 | // truncation is legal. |
| 3006 | if (SE->getTypeSizeInBits(BackedgeTakenCount->getType()) > |
| 3007 | IdxTy->getPrimitiveSizeInBits()) |
| 3008 | BackedgeTakenCount = SE->getTruncateOrNoop(BackedgeTakenCount, IdxTy); |
| 3009 | BackedgeTakenCount = SE->getNoopOrZeroExtend(BackedgeTakenCount, IdxTy); |
| 3010 | |
| 3011 | // Get the total trip count from the count by adding 1. |
| 3012 | const SCEV *ExitCount = SE->getAddExpr( |
| 3013 | BackedgeTakenCount, SE->getOne(BackedgeTakenCount->getType())); |
| 3014 | |
| 3015 | const DataLayout &DL = L->getHeader()->getModule()->getDataLayout(); |
| 3016 | |
| 3017 | // Expand the trip count and place the new instructions in the preheader. |
| 3018 | // Notice that the pre-header does not change, only the loop body. |
| 3019 | SCEVExpander Exp(*SE, DL, "induction"); |
| 3020 | |
| 3021 | // Count holds the overall loop count (N). |
| 3022 | TripCount = Exp.expandCodeFor(ExitCount, ExitCount->getType(), |
| 3023 | L->getLoopPreheader()->getTerminator()); |
| 3024 | |
| 3025 | if (TripCount->getType()->isPointerTy()) |
| 3026 | TripCount = |
| 3027 | CastInst::CreatePointerCast(TripCount, IdxTy, "exitcount.ptrcnt.to.int", |
| 3028 | L->getLoopPreheader()->getTerminator()); |
| 3029 | |
| 3030 | return TripCount; |
| 3031 | } |
| 3032 | |
| 3033 | Value *InnerLoopVectorizer::getOrCreateVectorTripCount(Loop *L) { |
| 3034 | if (VectorTripCount) |
| 3035 | return VectorTripCount; |
| 3036 | |
| 3037 | Value *TC = getOrCreateTripCount(L); |
| 3038 | IRBuilder<> Builder(L->getLoopPreheader()->getTerminator()); |
| 3039 | |
| 3040 | Type *Ty = TC->getType(); |
| 3041 | // This is where we can make the step a runtime constant. |
| 3042 | Value *Step = createStepForVF(Builder, Ty, VF, UF); |
| 3043 | |
| 3044 | // If the tail is to be folded by masking, round the number of iterations N |
| 3045 | // up to a multiple of Step instead of rounding down. This is done by first |
| 3046 | // adding Step-1 and then rounding down. Note that it's ok if this addition |
| 3047 | // overflows: the vector induction variable will eventually wrap to zero given |
| 3048 | // that it starts at zero and its Step is a power of two; the loop will then |
| 3049 | // exit, with the last early-exit vector comparison also producing all-true. |
| 3050 | if (Cost->foldTailByMasking()) { |
| 3051 | assert(isPowerOf2_32(VF.getKnownMinValue() * UF) &&(static_cast <bool> (isPowerOf2_32(VF.getKnownMinValue( ) * UF) && "VF*UF must be a power of 2 when folding tail by masking" ) ? void (0) : __assert_fail ("isPowerOf2_32(VF.getKnownMinValue() * UF) && \"VF*UF must be a power of 2 when folding tail by masking\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3052, __extension__ __PRETTY_FUNCTION__)) |
| 3052 | "VF*UF must be a power of 2 when folding tail by masking")(static_cast <bool> (isPowerOf2_32(VF.getKnownMinValue( ) * UF) && "VF*UF must be a power of 2 when folding tail by masking" ) ? void (0) : __assert_fail ("isPowerOf2_32(VF.getKnownMinValue() * UF) && \"VF*UF must be a power of 2 when folding tail by masking\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3052, __extension__ __PRETTY_FUNCTION__)); |
| 3053 | Value *NumLanes = getRuntimeVF(Builder, Ty, VF * UF); |
| 3054 | TC = Builder.CreateAdd( |
| 3055 | TC, Builder.CreateSub(NumLanes, ConstantInt::get(Ty, 1)), "n.rnd.up"); |
| 3056 | } |
| 3057 | |
| 3058 | // Now we need to generate the expression for the part of the loop that the |
| 3059 | // vectorized body will execute. This is equal to N - (N % Step) if scalar |
| 3060 | // iterations are not required for correctness, or N - Step, otherwise. Step |
| 3061 | // is equal to the vectorization factor (number of SIMD elements) times the |
| 3062 | // unroll factor (number of SIMD instructions). |
| 3063 | Value *R = Builder.CreateURem(TC, Step, "n.mod.vf"); |
| 3064 | |
| 3065 | // There are cases where we *must* run at least one iteration in the remainder |
| 3066 | // loop. See the cost model for when this can happen. If the step evenly |
| 3067 | // divides the trip count, we set the remainder to be equal to the step. If |
| 3068 | // the step does not evenly divide the trip count, no adjustment is necessary |
| 3069 | // since there will already be scalar iterations. Note that the minimum |
| 3070 | // iterations check ensures that N >= Step. |
| 3071 | if (Cost->requiresScalarEpilogue(VF)) { |
| 3072 | auto *IsZero = Builder.CreateICmpEQ(R, ConstantInt::get(R->getType(), 0)); |
| 3073 | R = Builder.CreateSelect(IsZero, Step, R); |
| 3074 | } |
| 3075 | |
| 3076 | VectorTripCount = Builder.CreateSub(TC, R, "n.vec"); |
| 3077 | |
| 3078 | return VectorTripCount; |
| 3079 | } |
| 3080 | |
| 3081 | Value *InnerLoopVectorizer::createBitOrPointerCast(Value *V, VectorType *DstVTy, |
| 3082 | const DataLayout &DL) { |
| 3083 | // Verify that V is a vector type with same number of elements as DstVTy. |
| 3084 | auto *DstFVTy = cast<FixedVectorType>(DstVTy); |
| 3085 | unsigned VF = DstFVTy->getNumElements(); |
| 3086 | auto *SrcVecTy = cast<FixedVectorType>(V->getType()); |
| 3087 | assert((VF == SrcVecTy->getNumElements()) && "Vector dimensions do not match")(static_cast <bool> ((VF == SrcVecTy->getNumElements ()) && "Vector dimensions do not match") ? void (0) : __assert_fail ("(VF == SrcVecTy->getNumElements()) && \"Vector dimensions do not match\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3087, __extension__ __PRETTY_FUNCTION__)); |
| 3088 | Type *SrcElemTy = SrcVecTy->getElementType(); |
| 3089 | Type *DstElemTy = DstFVTy->getElementType(); |
| 3090 | assert((DL.getTypeSizeInBits(SrcElemTy) == DL.getTypeSizeInBits(DstElemTy)) &&(static_cast <bool> ((DL.getTypeSizeInBits(SrcElemTy) == DL.getTypeSizeInBits(DstElemTy)) && "Vector elements must have same size" ) ? void (0) : __assert_fail ("(DL.getTypeSizeInBits(SrcElemTy) == DL.getTypeSizeInBits(DstElemTy)) && \"Vector elements must have same size\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3091, __extension__ __PRETTY_FUNCTION__)) |
| 3091 | "Vector elements must have same size")(static_cast <bool> ((DL.getTypeSizeInBits(SrcElemTy) == DL.getTypeSizeInBits(DstElemTy)) && "Vector elements must have same size" ) ? void (0) : __assert_fail ("(DL.getTypeSizeInBits(SrcElemTy) == DL.getTypeSizeInBits(DstElemTy)) && \"Vector elements must have same size\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3091, __extension__ __PRETTY_FUNCTION__)); |
| 3092 | |
| 3093 | // Do a direct cast if element types are castable. |
| 3094 | if (CastInst::isBitOrNoopPointerCastable(SrcElemTy, DstElemTy, DL)) { |
| 3095 | return Builder.CreateBitOrPointerCast(V, DstFVTy); |
| 3096 | } |
| 3097 | // V cannot be directly casted to desired vector type. |
| 3098 | // May happen when V is a floating point vector but DstVTy is a vector of |
| 3099 | // pointers or vice-versa. Handle this using a two-step bitcast using an |
| 3100 | // intermediate Integer type for the bitcast i.e. Ptr <-> Int <-> Float. |
| 3101 | assert((DstElemTy->isPointerTy() != SrcElemTy->isPointerTy()) &&(static_cast <bool> ((DstElemTy->isPointerTy() != SrcElemTy ->isPointerTy()) && "Only one type should be a pointer type" ) ? void (0) : __assert_fail ("(DstElemTy->isPointerTy() != SrcElemTy->isPointerTy()) && \"Only one type should be a pointer type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3102, __extension__ __PRETTY_FUNCTION__)) |
| 3102 | "Only one type should be a pointer type")(static_cast <bool> ((DstElemTy->isPointerTy() != SrcElemTy ->isPointerTy()) && "Only one type should be a pointer type" ) ? void (0) : __assert_fail ("(DstElemTy->isPointerTy() != SrcElemTy->isPointerTy()) && \"Only one type should be a pointer type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3102, __extension__ __PRETTY_FUNCTION__)); |
| 3103 | assert((DstElemTy->isFloatingPointTy() != SrcElemTy->isFloatingPointTy()) &&(static_cast <bool> ((DstElemTy->isFloatingPointTy() != SrcElemTy->isFloatingPointTy()) && "Only one type should be a floating point type" ) ? void (0) : __assert_fail ("(DstElemTy->isFloatingPointTy() != SrcElemTy->isFloatingPointTy()) && \"Only one type should be a floating point type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3104, __extension__ __PRETTY_FUNCTION__)) |
| 3104 | "Only one type should be a floating point type")(static_cast <bool> ((DstElemTy->isFloatingPointTy() != SrcElemTy->isFloatingPointTy()) && "Only one type should be a floating point type" ) ? void (0) : __assert_fail ("(DstElemTy->isFloatingPointTy() != SrcElemTy->isFloatingPointTy()) && \"Only one type should be a floating point type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3104, __extension__ __PRETTY_FUNCTION__)); |
| 3105 | Type *IntTy = |
| 3106 | IntegerType::getIntNTy(V->getContext(), DL.getTypeSizeInBits(SrcElemTy)); |
| 3107 | auto *VecIntTy = FixedVectorType::get(IntTy, VF); |
| 3108 | Value *CastVal = Builder.CreateBitOrPointerCast(V, VecIntTy); |
| 3109 | return Builder.CreateBitOrPointerCast(CastVal, DstFVTy); |
| 3110 | } |
| 3111 | |
| 3112 | void InnerLoopVectorizer::emitMinimumIterationCountCheck(Loop *L, |
| 3113 | BasicBlock *Bypass) { |
| 3114 | Value *Count = getOrCreateTripCount(L); |
| 3115 | // Reuse existing vector loop preheader for TC checks. |
| 3116 | // Note that new preheader block is generated for vector loop. |
| 3117 | BasicBlock *const TCCheckBlock = LoopVectorPreHeader; |
| 3118 | IRBuilder<> Builder(TCCheckBlock->getTerminator()); |
| 3119 | |
| 3120 | // Generate code to check if the loop's trip count is less than VF * UF, or |
| 3121 | // equal to it in case a scalar epilogue is required; this implies that the |
| 3122 | // vector trip count is zero. This check also covers the case where adding one |
| 3123 | // to the backedge-taken count overflowed leading to an incorrect trip count |
| 3124 | // of zero. In this case we will also jump to the scalar loop. |
| 3125 | auto P = Cost->requiresScalarEpilogue(VF) ? ICmpInst::ICMP_ULE |
| 3126 | : ICmpInst::ICMP_ULT; |
| 3127 | |
| 3128 | // If tail is to be folded, vector loop takes care of all iterations. |
| 3129 | Value *CheckMinIters = Builder.getFalse(); |
| 3130 | if (!Cost->foldTailByMasking()) { |
| 3131 | Value *Step = createStepForVF(Builder, Count->getType(), VF, UF); |
| 3132 | CheckMinIters = Builder.CreateICmp(P, Count, Step, "min.iters.check"); |
| 3133 | } |
| 3134 | // Create new preheader for vector loop. |
| 3135 | LoopVectorPreHeader = |
| 3136 | SplitBlock(TCCheckBlock, TCCheckBlock->getTerminator(), DT, LI, nullptr, |
| 3137 | "vector.ph"); |
| 3138 | |
| 3139 | assert(DT->properlyDominates(DT->getNode(TCCheckBlock),(static_cast <bool> (DT->properlyDominates(DT->getNode (TCCheckBlock), DT->getNode(Bypass)->getIDom()) && "TC check is expected to dominate Bypass") ? void (0) : __assert_fail ("DT->properlyDominates(DT->getNode(TCCheckBlock), DT->getNode(Bypass)->getIDom()) && \"TC check is expected to dominate Bypass\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3141, __extension__ __PRETTY_FUNCTION__)) |
| 3140 | DT->getNode(Bypass)->getIDom()) &&(static_cast <bool> (DT->properlyDominates(DT->getNode (TCCheckBlock), DT->getNode(Bypass)->getIDom()) && "TC check is expected to dominate Bypass") ? void (0) : __assert_fail ("DT->properlyDominates(DT->getNode(TCCheckBlock), DT->getNode(Bypass)->getIDom()) && \"TC check is expected to dominate Bypass\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3141, __extension__ __PRETTY_FUNCTION__)) |
| 3141 | "TC check is expected to dominate Bypass")(static_cast <bool> (DT->properlyDominates(DT->getNode (TCCheckBlock), DT->getNode(Bypass)->getIDom()) && "TC check is expected to dominate Bypass") ? void (0) : __assert_fail ("DT->properlyDominates(DT->getNode(TCCheckBlock), DT->getNode(Bypass)->getIDom()) && \"TC check is expected to dominate Bypass\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3141, __extension__ __PRETTY_FUNCTION__)); |
| 3142 | |
| 3143 | // Update dominator for Bypass & LoopExit (if needed). |
| 3144 | DT->changeImmediateDominator(Bypass, TCCheckBlock); |
| 3145 | if (!Cost->requiresScalarEpilogue(VF)) |
| 3146 | // If there is an epilogue which must run, there's no edge from the |
| 3147 | // middle block to exit blocks and thus no need to update the immediate |
| 3148 | // dominator of the exit blocks. |
| 3149 | DT->changeImmediateDominator(LoopExitBlock, TCCheckBlock); |
| 3150 | |
| 3151 | ReplaceInstWithInst( |
| 3152 | TCCheckBlock->getTerminator(), |
| 3153 | BranchInst::Create(Bypass, LoopVectorPreHeader, CheckMinIters)); |
| 3154 | LoopBypassBlocks.push_back(TCCheckBlock); |
| 3155 | } |
| 3156 | |
| 3157 | BasicBlock *InnerLoopVectorizer::emitSCEVChecks(Loop *L, BasicBlock *Bypass) { |
| 3158 | |
| 3159 | BasicBlock *const SCEVCheckBlock = |
| 3160 | RTChecks.emitSCEVChecks(L, Bypass, LoopVectorPreHeader, LoopExitBlock); |
| 3161 | if (!SCEVCheckBlock) |
| 3162 | return nullptr; |
| 3163 | |
| 3164 | assert(!(SCEVCheckBlock->getParent()->hasOptSize() ||(static_cast <bool> (!(SCEVCheckBlock->getParent()-> hasOptSize() || (OptForSizeBasedOnProfile && Cost-> Hints->getForce() != LoopVectorizeHints::FK_Enabled)) && "Cannot SCEV check stride or overflow when optimizing for size" ) ? void (0) : __assert_fail ("!(SCEVCheckBlock->getParent()->hasOptSize() || (OptForSizeBasedOnProfile && Cost->Hints->getForce() != LoopVectorizeHints::FK_Enabled)) && \"Cannot SCEV check stride or overflow when optimizing for size\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3167, __extension__ __PRETTY_FUNCTION__)) |
| 3165 | (OptForSizeBasedOnProfile &&(static_cast <bool> (!(SCEVCheckBlock->getParent()-> hasOptSize() || (OptForSizeBasedOnProfile && Cost-> Hints->getForce() != LoopVectorizeHints::FK_Enabled)) && "Cannot SCEV check stride or overflow when optimizing for size" ) ? void (0) : __assert_fail ("!(SCEVCheckBlock->getParent()->hasOptSize() || (OptForSizeBasedOnProfile && Cost->Hints->getForce() != LoopVectorizeHints::FK_Enabled)) && \"Cannot SCEV check stride or overflow when optimizing for size\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3167, __extension__ __PRETTY_FUNCTION__)) |
| 3166 | Cost->Hints->getForce() != LoopVectorizeHints::FK_Enabled)) &&(static_cast <bool> (!(SCEVCheckBlock->getParent()-> hasOptSize() || (OptForSizeBasedOnProfile && Cost-> Hints->getForce() != LoopVectorizeHints::FK_Enabled)) && "Cannot SCEV check stride or overflow when optimizing for size" ) ? void (0) : __assert_fail ("!(SCEVCheckBlock->getParent()->hasOptSize() || (OptForSizeBasedOnProfile && Cost->Hints->getForce() != LoopVectorizeHints::FK_Enabled)) && \"Cannot SCEV check stride or overflow when optimizing for size\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3167, __extension__ __PRETTY_FUNCTION__)) |
| 3167 | "Cannot SCEV check stride or overflow when optimizing for size")(static_cast <bool> (!(SCEVCheckBlock->getParent()-> hasOptSize() || (OptForSizeBasedOnProfile && Cost-> Hints->getForce() != LoopVectorizeHints::FK_Enabled)) && "Cannot SCEV check stride or overflow when optimizing for size" ) ? void (0) : __assert_fail ("!(SCEVCheckBlock->getParent()->hasOptSize() || (OptForSizeBasedOnProfile && Cost->Hints->getForce() != LoopVectorizeHints::FK_Enabled)) && \"Cannot SCEV check stride or overflow when optimizing for size\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3167, __extension__ __PRETTY_FUNCTION__)); |
| 3168 | |
| 3169 | |
| 3170 | // Update dominator only if this is first RT check. |
| 3171 | if (LoopBypassBlocks.empty()) { |
| 3172 | DT->changeImmediateDominator(Bypass, SCEVCheckBlock); |
| 3173 | if (!Cost->requiresScalarEpilogue(VF)) |
| 3174 | // If there is an epilogue which must run, there's no edge from the |
| 3175 | // middle block to exit blocks and thus no need to update the immediate |
| 3176 | // dominator of the exit blocks. |
| 3177 | DT->changeImmediateDominator(LoopExitBlock, SCEVCheckBlock); |
| 3178 | } |
| 3179 | |
| 3180 | LoopBypassBlocks.push_back(SCEVCheckBlock); |
| 3181 | AddedSafetyChecks = true; |
| 3182 | return SCEVCheckBlock; |
| 3183 | } |
| 3184 | |
| 3185 | BasicBlock *InnerLoopVectorizer::emitMemRuntimeChecks(Loop *L, |
| 3186 | BasicBlock *Bypass) { |
| 3187 | // VPlan-native path does not do any analysis for runtime checks currently. |
| 3188 | if (EnableVPlanNativePath) |
| 3189 | return nullptr; |
| 3190 | |
| 3191 | BasicBlock *const MemCheckBlock = |
| 3192 | RTChecks.emitMemRuntimeChecks(L, Bypass, LoopVectorPreHeader); |
| 3193 | |
| 3194 | // Check if we generated code that checks in runtime if arrays overlap. We put |
| 3195 | // the checks into a separate block to make the more common case of few |
| 3196 | // elements faster. |
| 3197 | if (!MemCheckBlock) |
| 3198 | return nullptr; |
| 3199 | |
| 3200 | if (MemCheckBlock->getParent()->hasOptSize() || OptForSizeBasedOnProfile) { |
| 3201 | assert(Cost->Hints->getForce() == LoopVectorizeHints::FK_Enabled &&(static_cast <bool> (Cost->Hints->getForce() == LoopVectorizeHints ::FK_Enabled && "Cannot emit memory checks when optimizing for size, unless forced " "to vectorize.") ? void (0) : __assert_fail ("Cost->Hints->getForce() == LoopVectorizeHints::FK_Enabled && \"Cannot emit memory checks when optimizing for size, unless forced \" \"to vectorize.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3203, __extension__ __PRETTY_FUNCTION__)) |
| 3202 | "Cannot emit memory checks when optimizing for size, unless forced "(static_cast <bool> (Cost->Hints->getForce() == LoopVectorizeHints ::FK_Enabled && "Cannot emit memory checks when optimizing for size, unless forced " "to vectorize.") ? void (0) : __assert_fail ("Cost->Hints->getForce() == LoopVectorizeHints::FK_Enabled && \"Cannot emit memory checks when optimizing for size, unless forced \" \"to vectorize.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3203, __extension__ __PRETTY_FUNCTION__)) |
| 3203 | "to vectorize.")(static_cast <bool> (Cost->Hints->getForce() == LoopVectorizeHints ::FK_Enabled && "Cannot emit memory checks when optimizing for size, unless forced " "to vectorize.") ? void (0) : __assert_fail ("Cost->Hints->getForce() == LoopVectorizeHints::FK_Enabled && \"Cannot emit memory checks when optimizing for size, unless forced \" \"to vectorize.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3203, __extension__ __PRETTY_FUNCTION__)); |
| 3204 | ORE->emit([&]() { |
| 3205 | return OptimizationRemarkAnalysis(DEBUG_TYPE"loop-vectorize", "VectorizationCodeSize", |
| 3206 | L->getStartLoc(), L->getHeader()) |
| 3207 | << "Code-size may be reduced by not forcing " |
| 3208 | "vectorization, or by source-code modifications " |
| 3209 | "eliminating the need for runtime checks " |
| 3210 | "(e.g., adding 'restrict')."; |
| 3211 | }); |
| 3212 | } |
| 3213 | |
| 3214 | LoopBypassBlocks.push_back(MemCheckBlock); |
| 3215 | |
| 3216 | AddedSafetyChecks = true; |
| 3217 | |
| 3218 | // We currently don't use LoopVersioning for the actual loop cloning but we |
| 3219 | // still use it to add the noalias metadata. |
| 3220 | LVer = std::make_unique<LoopVersioning>( |
| 3221 | *Legal->getLAI(), |
| 3222 | Legal->getLAI()->getRuntimePointerChecking()->getChecks(), OrigLoop, LI, |
| 3223 | DT, PSE.getSE()); |
| 3224 | LVer->prepareNoAliasMetadata(); |
| 3225 | return MemCheckBlock; |
| 3226 | } |
| 3227 | |
| 3228 | Value *InnerLoopVectorizer::emitTransformedIndex( |
| 3229 | IRBuilder<> &B, Value *Index, ScalarEvolution *SE, const DataLayout &DL, |
| 3230 | const InductionDescriptor &ID, BasicBlock *VectorHeader) const { |
| 3231 | |
| 3232 | SCEVExpander Exp(*SE, DL, "induction"); |
| 3233 | auto Step = ID.getStep(); |
| 3234 | auto StartValue = ID.getStartValue(); |
| 3235 | assert(Index->getType()->getScalarType() == Step->getType() &&(static_cast <bool> (Index->getType()->getScalarType () == Step->getType() && "Index scalar type does not match StepValue type" ) ? void (0) : __assert_fail ("Index->getType()->getScalarType() == Step->getType() && \"Index scalar type does not match StepValue type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3236, __extension__ __PRETTY_FUNCTION__)) |
| 3236 | "Index scalar type does not match StepValue type")(static_cast <bool> (Index->getType()->getScalarType () == Step->getType() && "Index scalar type does not match StepValue type" ) ? void (0) : __assert_fail ("Index->getType()->getScalarType() == Step->getType() && \"Index scalar type does not match StepValue type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3236, __extension__ __PRETTY_FUNCTION__)); |
| 3237 | |
| 3238 | // Note: the IR at this point is broken. We cannot use SE to create any new |
| 3239 | // SCEV and then expand it, hoping that SCEV's simplification will give us |
| 3240 | // a more optimal code. Unfortunately, attempt of doing so on invalid IR may |
| 3241 | // lead to various SCEV crashes. So all we can do is to use builder and rely |
| 3242 | // on InstCombine for future simplifications. Here we handle some trivial |
| 3243 | // cases only. |
| 3244 | auto CreateAdd = [&B](Value *X, Value *Y) { |
| 3245 | assert(X->getType() == Y->getType() && "Types don't match!")(static_cast <bool> (X->getType() == Y->getType() && "Types don't match!") ? void (0) : __assert_fail ( "X->getType() == Y->getType() && \"Types don't match!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3245, __extension__ __PRETTY_FUNCTION__)); |
| 3246 | if (auto *CX = dyn_cast<ConstantInt>(X)) |
| 3247 | if (CX->isZero()) |
| 3248 | return Y; |
| 3249 | if (auto *CY = dyn_cast<ConstantInt>(Y)) |
| 3250 | if (CY->isZero()) |
| 3251 | return X; |
| 3252 | return B.CreateAdd(X, Y); |
| 3253 | }; |
| 3254 | |
| 3255 | // We allow X to be a vector type, in which case Y will potentially be |
| 3256 | // splatted into a vector with the same element count. |
| 3257 | auto CreateMul = [&B](Value *X, Value *Y) { |
| 3258 | assert(X->getType()->getScalarType() == Y->getType() &&(static_cast <bool> (X->getType()->getScalarType( ) == Y->getType() && "Types don't match!") ? void ( 0) : __assert_fail ("X->getType()->getScalarType() == Y->getType() && \"Types don't match!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3259, __extension__ __PRETTY_FUNCTION__)) |
| 3259 | "Types don't match!")(static_cast <bool> (X->getType()->getScalarType( ) == Y->getType() && "Types don't match!") ? void ( 0) : __assert_fail ("X->getType()->getScalarType() == Y->getType() && \"Types don't match!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3259, __extension__ __PRETTY_FUNCTION__)); |
| 3260 | if (auto *CX = dyn_cast<ConstantInt>(X)) |
| 3261 | if (CX->isOne()) |
| 3262 | return Y; |
| 3263 | if (auto *CY = dyn_cast<ConstantInt>(Y)) |
| 3264 | if (CY->isOne()) |
| 3265 | return X; |
| 3266 | VectorType *XVTy = dyn_cast<VectorType>(X->getType()); |
| 3267 | if (XVTy && !isa<VectorType>(Y->getType())) |
| 3268 | Y = B.CreateVectorSplat(XVTy->getElementCount(), Y); |
| 3269 | return B.CreateMul(X, Y); |
| 3270 | }; |
| 3271 | |
| 3272 | // Get a suitable insert point for SCEV expansion. For blocks in the vector |
| 3273 | // loop, choose the end of the vector loop header (=VectorHeader), because |
| 3274 | // the DomTree is not kept up-to-date for additional blocks generated in the |
| 3275 | // vector loop. By using the header as insertion point, we guarantee that the |
| 3276 | // expanded instructions dominate all their uses. |
| 3277 | auto GetInsertPoint = [this, &B, VectorHeader]() { |
| 3278 | BasicBlock *InsertBB = B.GetInsertPoint()->getParent(); |
| 3279 | if (InsertBB != LoopVectorBody && |
| 3280 | LI->getLoopFor(VectorHeader) == LI->getLoopFor(InsertBB)) |
| 3281 | return VectorHeader->getTerminator(); |
| 3282 | return &*B.GetInsertPoint(); |
| 3283 | }; |
| 3284 | |
| 3285 | switch (ID.getKind()) { |
| 3286 | case InductionDescriptor::IK_IntInduction: { |
| 3287 | assert(!isa<VectorType>(Index->getType()) &&(static_cast <bool> (!isa<VectorType>(Index->getType ()) && "Vector indices not supported for integer inductions yet" ) ? void (0) : __assert_fail ("!isa<VectorType>(Index->getType()) && \"Vector indices not supported for integer inductions yet\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3288, __extension__ __PRETTY_FUNCTION__)) |
| 3288 | "Vector indices not supported for integer inductions yet")(static_cast <bool> (!isa<VectorType>(Index->getType ()) && "Vector indices not supported for integer inductions yet" ) ? void (0) : __assert_fail ("!isa<VectorType>(Index->getType()) && \"Vector indices not supported for integer inductions yet\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3288, __extension__ __PRETTY_FUNCTION__)); |
| 3289 | assert(Index->getType() == StartValue->getType() &&(static_cast <bool> (Index->getType() == StartValue-> getType() && "Index type does not match StartValue type" ) ? void (0) : __assert_fail ("Index->getType() == StartValue->getType() && \"Index type does not match StartValue type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3290, __extension__ __PRETTY_FUNCTION__)) |
| 3290 | "Index type does not match StartValue type")(static_cast <bool> (Index->getType() == StartValue-> getType() && "Index type does not match StartValue type" ) ? void (0) : __assert_fail ("Index->getType() == StartValue->getType() && \"Index type does not match StartValue type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3290, __extension__ __PRETTY_FUNCTION__)); |
| 3291 | if (ID.getConstIntStepValue() && ID.getConstIntStepValue()->isMinusOne()) |
| 3292 | return B.CreateSub(StartValue, Index); |
| 3293 | auto *Offset = CreateMul( |
| 3294 | Index, Exp.expandCodeFor(Step, Index->getType(), GetInsertPoint())); |
| 3295 | return CreateAdd(StartValue, Offset); |
| 3296 | } |
| 3297 | case InductionDescriptor::IK_PtrInduction: { |
| 3298 | assert(isa<SCEVConstant>(Step) &&(static_cast <bool> (isa<SCEVConstant>(Step) && "Expected constant step for pointer induction") ? void (0) : __assert_fail ("isa<SCEVConstant>(Step) && \"Expected constant step for pointer induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3299, __extension__ __PRETTY_FUNCTION__)) |
| 3299 | "Expected constant step for pointer induction")(static_cast <bool> (isa<SCEVConstant>(Step) && "Expected constant step for pointer induction") ? void (0) : __assert_fail ("isa<SCEVConstant>(Step) && \"Expected constant step for pointer induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3299, __extension__ __PRETTY_FUNCTION__)); |
| 3300 | return B.CreateGEP( |
| 3301 | ID.getElementType(), StartValue, |
| 3302 | CreateMul(Index, |
| 3303 | Exp.expandCodeFor(Step, Index->getType()->getScalarType(), |
| 3304 | GetInsertPoint()))); |
| 3305 | } |
| 3306 | case InductionDescriptor::IK_FpInduction: { |
| 3307 | assert(!isa<VectorType>(Index->getType()) &&(static_cast <bool> (!isa<VectorType>(Index->getType ()) && "Vector indices not supported for FP inductions yet" ) ? void (0) : __assert_fail ("!isa<VectorType>(Index->getType()) && \"Vector indices not supported for FP inductions yet\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3308, __extension__ __PRETTY_FUNCTION__)) |
| 3308 | "Vector indices not supported for FP inductions yet")(static_cast <bool> (!isa<VectorType>(Index->getType ()) && "Vector indices not supported for FP inductions yet" ) ? void (0) : __assert_fail ("!isa<VectorType>(Index->getType()) && \"Vector indices not supported for FP inductions yet\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3308, __extension__ __PRETTY_FUNCTION__)); |
| 3309 | assert(Step->getType()->isFloatingPointTy() && "Expected FP Step value")(static_cast <bool> (Step->getType()->isFloatingPointTy () && "Expected FP Step value") ? void (0) : __assert_fail ("Step->getType()->isFloatingPointTy() && \"Expected FP Step value\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3309, __extension__ __PRETTY_FUNCTION__)); |
| 3310 | auto InductionBinOp = ID.getInductionBinOp(); |
| 3311 | assert(InductionBinOp &&(static_cast <bool> (InductionBinOp && (InductionBinOp ->getOpcode() == Instruction::FAdd || InductionBinOp->getOpcode () == Instruction::FSub) && "Original bin op should be defined for FP induction" ) ? void (0) : __assert_fail ("InductionBinOp && (InductionBinOp->getOpcode() == Instruction::FAdd || InductionBinOp->getOpcode() == Instruction::FSub) && \"Original bin op should be defined for FP induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3314, __extension__ __PRETTY_FUNCTION__)) |
| 3312 | (InductionBinOp->getOpcode() == Instruction::FAdd ||(static_cast <bool> (InductionBinOp && (InductionBinOp ->getOpcode() == Instruction::FAdd || InductionBinOp->getOpcode () == Instruction::FSub) && "Original bin op should be defined for FP induction" ) ? void (0) : __assert_fail ("InductionBinOp && (InductionBinOp->getOpcode() == Instruction::FAdd || InductionBinOp->getOpcode() == Instruction::FSub) && \"Original bin op should be defined for FP induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3314, __extension__ __PRETTY_FUNCTION__)) |
| 3313 | InductionBinOp->getOpcode() == Instruction::FSub) &&(static_cast <bool> (InductionBinOp && (InductionBinOp ->getOpcode() == Instruction::FAdd || InductionBinOp->getOpcode () == Instruction::FSub) && "Original bin op should be defined for FP induction" ) ? void (0) : __assert_fail ("InductionBinOp && (InductionBinOp->getOpcode() == Instruction::FAdd || InductionBinOp->getOpcode() == Instruction::FSub) && \"Original bin op should be defined for FP induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3314, __extension__ __PRETTY_FUNCTION__)) |
| 3314 | "Original bin op should be defined for FP induction")(static_cast <bool> (InductionBinOp && (InductionBinOp ->getOpcode() == Instruction::FAdd || InductionBinOp->getOpcode () == Instruction::FSub) && "Original bin op should be defined for FP induction" ) ? void (0) : __assert_fail ("InductionBinOp && (InductionBinOp->getOpcode() == Instruction::FAdd || InductionBinOp->getOpcode() == Instruction::FSub) && \"Original bin op should be defined for FP induction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3314, __extension__ __PRETTY_FUNCTION__)); |
| 3315 | |
| 3316 | Value *StepValue = cast<SCEVUnknown>(Step)->getValue(); |
| 3317 | Value *MulExp = B.CreateFMul(StepValue, Index); |
| 3318 | return B.CreateBinOp(InductionBinOp->getOpcode(), StartValue, MulExp, |
| 3319 | "induction"); |
| 3320 | } |
| 3321 | case InductionDescriptor::IK_NoInduction: |
| 3322 | return nullptr; |
| 3323 | } |
| 3324 | llvm_unreachable("invalid enum")::llvm::llvm_unreachable_internal("invalid enum", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 3324); |
| 3325 | } |
| 3326 | |
| 3327 | Loop *InnerLoopVectorizer::createVectorLoopSkeleton(StringRef Prefix) { |
| 3328 | LoopScalarBody = OrigLoop->getHeader(); |
| 3329 | LoopVectorPreHeader = OrigLoop->getLoopPreheader(); |
| 3330 | assert(LoopVectorPreHeader && "Invalid loop structure")(static_cast <bool> (LoopVectorPreHeader && "Invalid loop structure" ) ? void (0) : __assert_fail ("LoopVectorPreHeader && \"Invalid loop structure\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3330, __extension__ __PRETTY_FUNCTION__)); |
| 3331 | LoopExitBlock = OrigLoop->getUniqueExitBlock(); // may be nullptr |
| 3332 | assert((LoopExitBlock || Cost->requiresScalarEpilogue(VF)) &&(static_cast <bool> ((LoopExitBlock || Cost->requiresScalarEpilogue (VF)) && "multiple exit loop without required epilogue?" ) ? void (0) : __assert_fail ("(LoopExitBlock || Cost->requiresScalarEpilogue(VF)) && \"multiple exit loop without required epilogue?\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3333, __extension__ __PRETTY_FUNCTION__)) |
| 3333 | "multiple exit loop without required epilogue?")(static_cast <bool> ((LoopExitBlock || Cost->requiresScalarEpilogue (VF)) && "multiple exit loop without required epilogue?" ) ? void (0) : __assert_fail ("(LoopExitBlock || Cost->requiresScalarEpilogue(VF)) && \"multiple exit loop without required epilogue?\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3333, __extension__ __PRETTY_FUNCTION__)); |
| 3334 | |
| 3335 | LoopMiddleBlock = |
| 3336 | SplitBlock(LoopVectorPreHeader, LoopVectorPreHeader->getTerminator(), DT, |
| 3337 | LI, nullptr, Twine(Prefix) + "middle.block"); |
| 3338 | LoopScalarPreHeader = |
| 3339 | SplitBlock(LoopMiddleBlock, LoopMiddleBlock->getTerminator(), DT, LI, |
| 3340 | nullptr, Twine(Prefix) + "scalar.ph"); |
| 3341 | |
| 3342 | auto *ScalarLatchTerm = OrigLoop->getLoopLatch()->getTerminator(); |
| 3343 | |
| 3344 | // Set up the middle block terminator. Two cases: |
| 3345 | // 1) If we know that we must execute the scalar epilogue, emit an |
| 3346 | // unconditional branch. |
| 3347 | // 2) Otherwise, we must have a single unique exit block (due to how we |
| 3348 | // implement the multiple exit case). In this case, set up a conditonal |
| 3349 | // branch from the middle block to the loop scalar preheader, and the |
| 3350 | // exit block. completeLoopSkeleton will update the condition to use an |
| 3351 | // iteration check, if required to decide whether to execute the remainder. |
| 3352 | BranchInst *BrInst = Cost->requiresScalarEpilogue(VF) ? |
| 3353 | BranchInst::Create(LoopScalarPreHeader) : |
| 3354 | BranchInst::Create(LoopExitBlock, LoopScalarPreHeader, |
| 3355 | Builder.getTrue()); |
| 3356 | BrInst->setDebugLoc(ScalarLatchTerm->getDebugLoc()); |
| 3357 | ReplaceInstWithInst(LoopMiddleBlock->getTerminator(), BrInst); |
| 3358 | |
| 3359 | // We intentionally don't let SplitBlock to update LoopInfo since |
| 3360 | // LoopVectorBody should belong to another loop than LoopVectorPreHeader. |
| 3361 | // LoopVectorBody is explicitly added to the correct place few lines later. |
| 3362 | LoopVectorBody = |
| 3363 | SplitBlock(LoopVectorPreHeader, LoopVectorPreHeader->getTerminator(), DT, |
| 3364 | nullptr, nullptr, Twine(Prefix) + "vector.body"); |
| 3365 | |
| 3366 | // Update dominator for loop exit. |
| 3367 | if (!Cost->requiresScalarEpilogue(VF)) |
| 3368 | // If there is an epilogue which must run, there's no edge from the |
| 3369 | // middle block to exit blocks and thus no need to update the immediate |
| 3370 | // dominator of the exit blocks. |
| 3371 | DT->changeImmediateDominator(LoopExitBlock, LoopMiddleBlock); |
| 3372 | |
| 3373 | // Create and register the new vector loop. |
| 3374 | Loop *Lp = LI->AllocateLoop(); |
| 3375 | Loop *ParentLoop = OrigLoop->getParentLoop(); |
| 3376 | |
| 3377 | // Insert the new loop into the loop nest and register the new basic blocks |
| 3378 | // before calling any utilities such as SCEV that require valid LoopInfo. |
| 3379 | if (ParentLoop) { |
| 3380 | ParentLoop->addChildLoop(Lp); |
| 3381 | } else { |
| 3382 | LI->addTopLevelLoop(Lp); |
| 3383 | } |
| 3384 | Lp->addBasicBlockToLoop(LoopVectorBody, *LI); |
| 3385 | return Lp; |
| 3386 | } |
| 3387 | |
| 3388 | void InnerLoopVectorizer::createInductionResumeValues( |
| 3389 | Loop *L, std::pair<BasicBlock *, Value *> AdditionalBypass) { |
| 3390 | assert(((AdditionalBypass.first && AdditionalBypass.second) ||(static_cast <bool> (((AdditionalBypass.first && AdditionalBypass.second) || (!AdditionalBypass.first && !AdditionalBypass.second)) && "Inconsistent information about additional bypass." ) ? void (0) : __assert_fail ("((AdditionalBypass.first && AdditionalBypass.second) || (!AdditionalBypass.first && !AdditionalBypass.second)) && \"Inconsistent information about additional bypass.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3392, __extension__ __PRETTY_FUNCTION__)) |
| 3391 | (!AdditionalBypass.first && !AdditionalBypass.second)) &&(static_cast <bool> (((AdditionalBypass.first && AdditionalBypass.second) || (!AdditionalBypass.first && !AdditionalBypass.second)) && "Inconsistent information about additional bypass." ) ? void (0) : __assert_fail ("((AdditionalBypass.first && AdditionalBypass.second) || (!AdditionalBypass.first && !AdditionalBypass.second)) && \"Inconsistent information about additional bypass.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3392, __extension__ __PRETTY_FUNCTION__)) |
| 3392 | "Inconsistent information about additional bypass.")(static_cast <bool> (((AdditionalBypass.first && AdditionalBypass.second) || (!AdditionalBypass.first && !AdditionalBypass.second)) && "Inconsistent information about additional bypass." ) ? void (0) : __assert_fail ("((AdditionalBypass.first && AdditionalBypass.second) || (!AdditionalBypass.first && !AdditionalBypass.second)) && \"Inconsistent information about additional bypass.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3392, __extension__ __PRETTY_FUNCTION__)); |
| 3393 | |
| 3394 | Value *VectorTripCount = getOrCreateVectorTripCount(L); |
| 3395 | assert(VectorTripCount && L && "Expected valid arguments")(static_cast <bool> (VectorTripCount && L && "Expected valid arguments") ? void (0) : __assert_fail ("VectorTripCount && L && \"Expected valid arguments\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3395, __extension__ __PRETTY_FUNCTION__)); |
| 3396 | // We are going to resume the execution of the scalar loop. |
| 3397 | // Go over all of the induction variables that we found and fix the |
| 3398 | // PHIs that are left in the scalar version of the loop. |
| 3399 | // The starting values of PHI nodes depend on the counter of the last |
| 3400 | // iteration in the vectorized loop. |
| 3401 | // If we come from a bypass edge then we need to start from the original |
| 3402 | // start value. |
| 3403 | Instruction *OldInduction = Legal->getPrimaryInduction(); |
| 3404 | for (auto &InductionEntry : Legal->getInductionVars()) { |
| 3405 | PHINode *OrigPhi = InductionEntry.first; |
| 3406 | InductionDescriptor II = InductionEntry.second; |
| 3407 | |
| 3408 | // Create phi nodes to merge from the backedge-taken check block. |
| 3409 | PHINode *BCResumeVal = |
| 3410 | PHINode::Create(OrigPhi->getType(), 3, "bc.resume.val", |
| 3411 | LoopScalarPreHeader->getTerminator()); |
| 3412 | // Copy original phi DL over to the new one. |
| 3413 | BCResumeVal->setDebugLoc(OrigPhi->getDebugLoc()); |
| 3414 | Value *&EndValue = IVEndValues[OrigPhi]; |
| 3415 | Value *EndValueFromAdditionalBypass = AdditionalBypass.second; |
| 3416 | if (OrigPhi == OldInduction) { |
| 3417 | // We know what the end value is. |
| 3418 | EndValue = VectorTripCount; |
| 3419 | } else { |
| 3420 | IRBuilder<> B(L->getLoopPreheader()->getTerminator()); |
| 3421 | |
| 3422 | // Fast-math-flags propagate from the original induction instruction. |
| 3423 | if (II.getInductionBinOp() && isa<FPMathOperator>(II.getInductionBinOp())) |
| 3424 | B.setFastMathFlags(II.getInductionBinOp()->getFastMathFlags()); |
| 3425 | |
| 3426 | Type *StepType = II.getStep()->getType(); |
| 3427 | Instruction::CastOps CastOp = |
| 3428 | CastInst::getCastOpcode(VectorTripCount, true, StepType, true); |
| 3429 | Value *CRD = B.CreateCast(CastOp, VectorTripCount, StepType, "cast.crd"); |
| 3430 | const DataLayout &DL = LoopScalarBody->getModule()->getDataLayout(); |
| 3431 | EndValue = |
| 3432 | emitTransformedIndex(B, CRD, PSE.getSE(), DL, II, LoopVectorBody); |
| 3433 | EndValue->setName("ind.end"); |
| 3434 | |
| 3435 | // Compute the end value for the additional bypass (if applicable). |
| 3436 | if (AdditionalBypass.first) { |
| 3437 | B.SetInsertPoint(&(*AdditionalBypass.first->getFirstInsertionPt())); |
| 3438 | CastOp = CastInst::getCastOpcode(AdditionalBypass.second, true, |
| 3439 | StepType, true); |
| 3440 | CRD = |
| 3441 | B.CreateCast(CastOp, AdditionalBypass.second, StepType, "cast.crd"); |
| 3442 | EndValueFromAdditionalBypass = |
| 3443 | emitTransformedIndex(B, CRD, PSE.getSE(), DL, II, LoopVectorBody); |
| 3444 | EndValueFromAdditionalBypass->setName("ind.end"); |
| 3445 | } |
| 3446 | } |
| 3447 | // The new PHI merges the original incoming value, in case of a bypass, |
| 3448 | // or the value at the end of the vectorized loop. |
| 3449 | BCResumeVal->addIncoming(EndValue, LoopMiddleBlock); |
| 3450 | |
| 3451 | // Fix the scalar body counter (PHI node). |
| 3452 | // The old induction's phi node in the scalar body needs the truncated |
| 3453 | // value. |
| 3454 | for (BasicBlock *BB : LoopBypassBlocks) |
| 3455 | BCResumeVal->addIncoming(II.getStartValue(), BB); |
| 3456 | |
| 3457 | if (AdditionalBypass.first) |
| 3458 | BCResumeVal->setIncomingValueForBlock(AdditionalBypass.first, |
| 3459 | EndValueFromAdditionalBypass); |
| 3460 | |
| 3461 | OrigPhi->setIncomingValueForBlock(LoopScalarPreHeader, BCResumeVal); |
| 3462 | } |
| 3463 | } |
| 3464 | |
| 3465 | BasicBlock *InnerLoopVectorizer::completeLoopSkeleton(Loop *L, |
| 3466 | MDNode *OrigLoopID) { |
| 3467 | assert(L && "Expected valid loop.")(static_cast <bool> (L && "Expected valid loop." ) ? void (0) : __assert_fail ("L && \"Expected valid loop.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3467, __extension__ __PRETTY_FUNCTION__)); |
| 3468 | |
| 3469 | // The trip counts should be cached by now. |
| 3470 | Value *Count = getOrCreateTripCount(L); |
| 3471 | Value *VectorTripCount = getOrCreateVectorTripCount(L); |
| 3472 | |
| 3473 | auto *ScalarLatchTerm = OrigLoop->getLoopLatch()->getTerminator(); |
| 3474 | |
| 3475 | // Add a check in the middle block to see if we have completed |
| 3476 | // all of the iterations in the first vector loop. Three cases: |
| 3477 | // 1) If we require a scalar epilogue, there is no conditional branch as |
| 3478 | // we unconditionally branch to the scalar preheader. Do nothing. |
| 3479 | // 2) If (N - N%VF) == N, then we *don't* need to run the remainder. |
| 3480 | // Thus if tail is to be folded, we know we don't need to run the |
| 3481 | // remainder and we can use the previous value for the condition (true). |
| 3482 | // 3) Otherwise, construct a runtime check. |
| 3483 | if (!Cost->requiresScalarEpilogue(VF) && !Cost->foldTailByMasking()) { |
| 3484 | Instruction *CmpN = CmpInst::Create(Instruction::ICmp, CmpInst::ICMP_EQ, |
| 3485 | Count, VectorTripCount, "cmp.n", |
| 3486 | LoopMiddleBlock->getTerminator()); |
| 3487 | |
| 3488 | // Here we use the same DebugLoc as the scalar loop latch terminator instead |
| 3489 | // of the corresponding compare because they may have ended up with |
| 3490 | // different line numbers and we want to avoid awkward line stepping while |
| 3491 | // debugging. Eg. if the compare has got a line number inside the loop. |
| 3492 | CmpN->setDebugLoc(ScalarLatchTerm->getDebugLoc()); |
| 3493 | cast<BranchInst>(LoopMiddleBlock->getTerminator())->setCondition(CmpN); |
| 3494 | } |
| 3495 | |
| 3496 | // Get ready to start creating new instructions into the vectorized body. |
| 3497 | assert(LoopVectorPreHeader == L->getLoopPreheader() &&(static_cast <bool> (LoopVectorPreHeader == L->getLoopPreheader () && "Inconsistent vector loop preheader") ? void (0 ) : __assert_fail ("LoopVectorPreHeader == L->getLoopPreheader() && \"Inconsistent vector loop preheader\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3498, __extension__ __PRETTY_FUNCTION__)) |
| 3498 | "Inconsistent vector loop preheader")(static_cast <bool> (LoopVectorPreHeader == L->getLoopPreheader () && "Inconsistent vector loop preheader") ? void (0 ) : __assert_fail ("LoopVectorPreHeader == L->getLoopPreheader() && \"Inconsistent vector loop preheader\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3498, __extension__ __PRETTY_FUNCTION__)); |
| 3499 | Builder.SetInsertPoint(&*LoopVectorBody->getFirstInsertionPt()); |
| 3500 | |
| 3501 | #ifdef EXPENSIVE_CHECKS |
| 3502 | assert(DT->verify(DominatorTree::VerificationLevel::Fast))(static_cast <bool> (DT->verify(DominatorTree::VerificationLevel ::Fast)) ? void (0) : __assert_fail ("DT->verify(DominatorTree::VerificationLevel::Fast)" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3502, __extension__ __PRETTY_FUNCTION__)); |
| 3503 | LI->verify(*DT); |
| 3504 | #endif |
| 3505 | |
| 3506 | return LoopVectorPreHeader; |
| 3507 | } |
| 3508 | |
| 3509 | std::pair<BasicBlock *, Value *> |
| 3510 | InnerLoopVectorizer::createVectorizedLoopSkeleton() { |
| 3511 | /* |
| 3512 | In this function we generate a new loop. The new loop will contain |
| 3513 | the vectorized instructions while the old loop will continue to run the |
| 3514 | scalar remainder. |
| 3515 | |
| 3516 | [ ] <-- loop iteration number check. |
| 3517 | / | |
| 3518 | / v |
| 3519 | | [ ] <-- vector loop bypass (may consist of multiple blocks). |
| 3520 | | / | |
| 3521 | | / v |
| 3522 | || [ ] <-- vector pre header. |
| 3523 | |/ | |
| 3524 | | v |
| 3525 | | [ ] \ |
| 3526 | | [ ]_| <-- vector loop. |
| 3527 | | | |
| 3528 | | v |
| 3529 | \ -[ ] <--- middle-block. |
| 3530 | \/ | |
| 3531 | /\ v |
| 3532 | | ->[ ] <--- new preheader. |
| 3533 | | | |
| 3534 | (opt) v <-- edge from middle to exit iff epilogue is not required. |
| 3535 | | [ ] \ |
| 3536 | | [ ]_| <-- old scalar loop to handle remainder (scalar epilogue). |
| 3537 | \ | |
| 3538 | \ v |
| 3539 | >[ ] <-- exit block(s). |
| 3540 | ... |
| 3541 | */ |
| 3542 | |
| 3543 | // Get the metadata of the original loop before it gets modified. |
| 3544 | MDNode *OrigLoopID = OrigLoop->getLoopID(); |
| 3545 | |
| 3546 | // Workaround! Compute the trip count of the original loop and cache it |
| 3547 | // before we start modifying the CFG. This code has a systemic problem |
| 3548 | // wherein it tries to run analysis over partially constructed IR; this is |
| 3549 | // wrong, and not simply for SCEV. The trip count of the original loop |
| 3550 | // simply happens to be prone to hitting this in practice. In theory, we |
| 3551 | // can hit the same issue for any SCEV, or ValueTracking query done during |
| 3552 | // mutation. See PR49900. |
| 3553 | getOrCreateTripCount(OrigLoop); |
| 3554 | |
| 3555 | // Create an empty vector loop, and prepare basic blocks for the runtime |
| 3556 | // checks. |
| 3557 | Loop *Lp = createVectorLoopSkeleton(""); |
| 3558 | |
| 3559 | // Now, compare the new count to zero. If it is zero skip the vector loop and |
| 3560 | // jump to the scalar loop. This check also covers the case where the |
| 3561 | // backedge-taken count is uint##_max: adding one to it will overflow leading |
| 3562 | // to an incorrect trip count of zero. In this (rare) case we will also jump |
| 3563 | // to the scalar loop. |
| 3564 | emitMinimumIterationCountCheck(Lp, LoopScalarPreHeader); |
| 3565 | |
| 3566 | // Generate the code to check any assumptions that we've made for SCEV |
| 3567 | // expressions. |
| 3568 | emitSCEVChecks(Lp, LoopScalarPreHeader); |
| 3569 | |
| 3570 | // Generate the code that checks in runtime if arrays overlap. We put the |
| 3571 | // checks into a separate block to make the more common case of few elements |
| 3572 | // faster. |
| 3573 | emitMemRuntimeChecks(Lp, LoopScalarPreHeader); |
| 3574 | |
| 3575 | createHeaderBranch(Lp); |
| 3576 | |
| 3577 | // Emit phis for the new starting index of the scalar loop. |
| 3578 | createInductionResumeValues(Lp); |
| 3579 | |
| 3580 | return {completeLoopSkeleton(Lp, OrigLoopID), nullptr}; |
| 3581 | } |
| 3582 | |
| 3583 | // Fix up external users of the induction variable. At this point, we are |
| 3584 | // in LCSSA form, with all external PHIs that use the IV having one input value, |
| 3585 | // coming from the remainder loop. We need those PHIs to also have a correct |
| 3586 | // value for the IV when arriving directly from the middle block. |
| 3587 | void InnerLoopVectorizer::fixupIVUsers(PHINode *OrigPhi, |
| 3588 | const InductionDescriptor &II, |
| 3589 | Value *CountRoundDown, Value *EndValue, |
| 3590 | BasicBlock *MiddleBlock) { |
| 3591 | // There are two kinds of external IV usages - those that use the value |
| 3592 | // computed in the last iteration (the PHI) and those that use the penultimate |
| 3593 | // value (the value that feeds into the phi from the loop latch). |
| 3594 | // We allow both, but they, obviously, have different values. |
| 3595 | |
| 3596 | assert(OrigLoop->getUniqueExitBlock() && "Expected a single exit block")(static_cast <bool> (OrigLoop->getUniqueExitBlock() && "Expected a single exit block") ? void (0) : __assert_fail ( "OrigLoop->getUniqueExitBlock() && \"Expected a single exit block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3596, __extension__ __PRETTY_FUNCTION__)); |
| 3597 | |
| 3598 | DenseMap<Value *, Value *> MissingVals; |
| 3599 | |
| 3600 | // An external user of the last iteration's value should see the value that |
| 3601 | // the remainder loop uses to initialize its own IV. |
| 3602 | Value *PostInc = OrigPhi->getIncomingValueForBlock(OrigLoop->getLoopLatch()); |
| 3603 | for (User *U : PostInc->users()) { |
| 3604 | Instruction *UI = cast<Instruction>(U); |
| 3605 | if (!OrigLoop->contains(UI)) { |
| 3606 | assert(isa<PHINode>(UI) && "Expected LCSSA form")(static_cast <bool> (isa<PHINode>(UI) && "Expected LCSSA form" ) ? void (0) : __assert_fail ("isa<PHINode>(UI) && \"Expected LCSSA form\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3606, __extension__ __PRETTY_FUNCTION__)); |
| 3607 | MissingVals[UI] = EndValue; |
| 3608 | } |
| 3609 | } |
| 3610 | |
| 3611 | // An external user of the penultimate value need to see EndValue - Step. |
| 3612 | // The simplest way to get this is to recompute it from the constituent SCEVs, |
| 3613 | // that is Start + (Step * (CRD - 1)). |
| 3614 | for (User *U : OrigPhi->users()) { |
| 3615 | auto *UI = cast<Instruction>(U); |
| 3616 | if (!OrigLoop->contains(UI)) { |
| 3617 | const DataLayout &DL = |
| 3618 | OrigLoop->getHeader()->getModule()->getDataLayout(); |
| 3619 | assert(isa<PHINode>(UI) && "Expected LCSSA form")(static_cast <bool> (isa<PHINode>(UI) && "Expected LCSSA form" ) ? void (0) : __assert_fail ("isa<PHINode>(UI) && \"Expected LCSSA form\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3619, __extension__ __PRETTY_FUNCTION__)); |
| 3620 | |
| 3621 | IRBuilder<> B(MiddleBlock->getTerminator()); |
| 3622 | |
| 3623 | // Fast-math-flags propagate from the original induction instruction. |
| 3624 | if (II.getInductionBinOp() && isa<FPMathOperator>(II.getInductionBinOp())) |
| 3625 | B.setFastMathFlags(II.getInductionBinOp()->getFastMathFlags()); |
| 3626 | |
| 3627 | Value *CountMinusOne = B.CreateSub( |
| 3628 | CountRoundDown, ConstantInt::get(CountRoundDown->getType(), 1)); |
| 3629 | Value *CMO = |
| 3630 | !II.getStep()->getType()->isIntegerTy() |
| 3631 | ? B.CreateCast(Instruction::SIToFP, CountMinusOne, |
| 3632 | II.getStep()->getType()) |
| 3633 | : B.CreateSExtOrTrunc(CountMinusOne, II.getStep()->getType()); |
| 3634 | CMO->setName("cast.cmo"); |
| 3635 | Value *Escape = |
| 3636 | emitTransformedIndex(B, CMO, PSE.getSE(), DL, II, LoopVectorBody); |
| 3637 | Escape->setName("ind.escape"); |
| 3638 | MissingVals[UI] = Escape; |
| 3639 | } |
| 3640 | } |
| 3641 | |
| 3642 | for (auto &I : MissingVals) { |
| 3643 | PHINode *PHI = cast<PHINode>(I.first); |
| 3644 | // One corner case we have to handle is two IVs "chasing" each-other, |
| 3645 | // that is %IV2 = phi [...], [ %IV1, %latch ] |
| 3646 | // In this case, if IV1 has an external use, we need to avoid adding both |
| 3647 | // "last value of IV1" and "penultimate value of IV2". So, verify that we |
| 3648 | // don't already have an incoming value for the middle block. |
| 3649 | if (PHI->getBasicBlockIndex(MiddleBlock) == -1) |
| 3650 | PHI->addIncoming(I.second, MiddleBlock); |
| 3651 | } |
| 3652 | } |
| 3653 | |
| 3654 | namespace { |
| 3655 | |
| 3656 | struct CSEDenseMapInfo { |
| 3657 | static bool canHandle(const Instruction *I) { |
| 3658 | return isa<InsertElementInst>(I) || isa<ExtractElementInst>(I) || |
| 3659 | isa<ShuffleVectorInst>(I) || isa<GetElementPtrInst>(I); |
| 3660 | } |
| 3661 | |
| 3662 | static inline Instruction *getEmptyKey() { |
| 3663 | return DenseMapInfo<Instruction *>::getEmptyKey(); |
| 3664 | } |
| 3665 | |
| 3666 | static inline Instruction *getTombstoneKey() { |
| 3667 | return DenseMapInfo<Instruction *>::getTombstoneKey(); |
| 3668 | } |
| 3669 | |
| 3670 | static unsigned getHashValue(const Instruction *I) { |
| 3671 | assert(canHandle(I) && "Unknown instruction!")(static_cast <bool> (canHandle(I) && "Unknown instruction!" ) ? void (0) : __assert_fail ("canHandle(I) && \"Unknown instruction!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3671, __extension__ __PRETTY_FUNCTION__)); |
| 3672 | return hash_combine(I->getOpcode(), hash_combine_range(I->value_op_begin(), |
| 3673 | I->value_op_end())); |
| 3674 | } |
| 3675 | |
| 3676 | static bool isEqual(const Instruction *LHS, const Instruction *RHS) { |
| 3677 | if (LHS == getEmptyKey() || RHS == getEmptyKey() || |
| 3678 | LHS == getTombstoneKey() || RHS == getTombstoneKey()) |
| 3679 | return LHS == RHS; |
| 3680 | return LHS->isIdenticalTo(RHS); |
| 3681 | } |
| 3682 | }; |
| 3683 | |
| 3684 | } // end anonymous namespace |
| 3685 | |
| 3686 | ///Perform cse of induction variable instructions. |
| 3687 | static void cse(BasicBlock *BB) { |
| 3688 | // Perform simple cse. |
| 3689 | SmallDenseMap<Instruction *, Instruction *, 4, CSEDenseMapInfo> CSEMap; |
| 3690 | for (Instruction &In : llvm::make_early_inc_range(*BB)) { |
| 3691 | if (!CSEDenseMapInfo::canHandle(&In)) |
| 3692 | continue; |
| 3693 | |
| 3694 | // Check if we can replace this instruction with any of the |
| 3695 | // visited instructions. |
| 3696 | if (Instruction *V = CSEMap.lookup(&In)) { |
| 3697 | In.replaceAllUsesWith(V); |
| 3698 | In.eraseFromParent(); |
| 3699 | continue; |
| 3700 | } |
| 3701 | |
| 3702 | CSEMap[&In] = &In; |
| 3703 | } |
| 3704 | } |
| 3705 | |
| 3706 | InstructionCost |
| 3707 | LoopVectorizationCostModel::getVectorCallCost(CallInst *CI, ElementCount VF, |
| 3708 | bool &NeedToScalarize) const { |
| 3709 | Function *F = CI->getCalledFunction(); |
| 3710 | Type *ScalarRetTy = CI->getType(); |
| 3711 | SmallVector<Type *, 4> Tys, ScalarTys; |
| 3712 | for (auto &ArgOp : CI->args()) |
| 3713 | ScalarTys.push_back(ArgOp->getType()); |
| 3714 | |
| 3715 | // Estimate cost of scalarized vector call. The source operands are assumed |
| 3716 | // to be vectors, so we need to extract individual elements from there, |
| 3717 | // execute VF scalar calls, and then gather the result into the vector return |
| 3718 | // value. |
| 3719 | InstructionCost ScalarCallCost = |
| 3720 | TTI.getCallInstrCost(F, ScalarRetTy, ScalarTys, TTI::TCK_RecipThroughput); |
| 3721 | if (VF.isScalar()) |
| 3722 | return ScalarCallCost; |
| 3723 | |
| 3724 | // Compute corresponding vector type for return value and arguments. |
| 3725 | Type *RetTy = ToVectorTy(ScalarRetTy, VF); |
| 3726 | for (Type *ScalarTy : ScalarTys) |
| 3727 | Tys.push_back(ToVectorTy(ScalarTy, VF)); |
| 3728 | |
| 3729 | // Compute costs of unpacking argument values for the scalar calls and |
| 3730 | // packing the return values to a vector. |
| 3731 | InstructionCost ScalarizationCost = getScalarizationOverhead(CI, VF); |
| 3732 | |
| 3733 | InstructionCost Cost = |
| 3734 | ScalarCallCost * VF.getKnownMinValue() + ScalarizationCost; |
| 3735 | |
| 3736 | // If we can't emit a vector call for this function, then the currently found |
| 3737 | // cost is the cost we need to return. |
| 3738 | NeedToScalarize = true; |
| 3739 | VFShape Shape = VFShape::get(*CI, VF, false /*HasGlobalPred*/); |
| 3740 | Function *VecFunc = VFDatabase(*CI).getVectorizedFunction(Shape); |
| 3741 | |
| 3742 | if (!TLI || CI->isNoBuiltin() || !VecFunc) |
| 3743 | return Cost; |
| 3744 | |
| 3745 | // If the corresponding vector cost is cheaper, return its cost. |
| 3746 | InstructionCost VectorCallCost = |
| 3747 | TTI.getCallInstrCost(nullptr, RetTy, Tys, TTI::TCK_RecipThroughput); |
| 3748 | if (VectorCallCost < Cost) { |
| 3749 | NeedToScalarize = false; |
| 3750 | Cost = VectorCallCost; |
| 3751 | } |
| 3752 | return Cost; |
| 3753 | } |
| 3754 | |
| 3755 | static Type *MaybeVectorizeType(Type *Elt, ElementCount VF) { |
| 3756 | if (VF.isScalar() || (!Elt->isIntOrPtrTy() && !Elt->isFloatingPointTy())) |
| 3757 | return Elt; |
| 3758 | return VectorType::get(Elt, VF); |
| 3759 | } |
| 3760 | |
| 3761 | InstructionCost |
| 3762 | LoopVectorizationCostModel::getVectorIntrinsicCost(CallInst *CI, |
| 3763 | ElementCount VF) const { |
| 3764 | Intrinsic::ID ID = getVectorIntrinsicIDForCall(CI, TLI); |
| 3765 | assert(ID && "Expected intrinsic call!")(static_cast <bool> (ID && "Expected intrinsic call!" ) ? void (0) : __assert_fail ("ID && \"Expected intrinsic call!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3765, __extension__ __PRETTY_FUNCTION__)); |
| 3766 | Type *RetTy = MaybeVectorizeType(CI->getType(), VF); |
| 3767 | FastMathFlags FMF; |
| 3768 | if (auto *FPMO = dyn_cast<FPMathOperator>(CI)) |
| 3769 | FMF = FPMO->getFastMathFlags(); |
| 3770 | |
| 3771 | SmallVector<const Value *> Arguments(CI->args()); |
| 3772 | FunctionType *FTy = CI->getCalledFunction()->getFunctionType(); |
| 3773 | SmallVector<Type *> ParamTys; |
| 3774 | std::transform(FTy->param_begin(), FTy->param_end(), |
| 3775 | std::back_inserter(ParamTys), |
| 3776 | [&](Type *Ty) { return MaybeVectorizeType(Ty, VF); }); |
| 3777 | |
| 3778 | IntrinsicCostAttributes CostAttrs(ID, RetTy, Arguments, ParamTys, FMF, |
| 3779 | dyn_cast<IntrinsicInst>(CI)); |
| 3780 | return TTI.getIntrinsicInstrCost(CostAttrs, |
| 3781 | TargetTransformInfo::TCK_RecipThroughput); |
| 3782 | } |
| 3783 | |
| 3784 | static Type *smallestIntegerVectorType(Type *T1, Type *T2) { |
| 3785 | auto *I1 = cast<IntegerType>(cast<VectorType>(T1)->getElementType()); |
| 3786 | auto *I2 = cast<IntegerType>(cast<VectorType>(T2)->getElementType()); |
| 3787 | return I1->getBitWidth() < I2->getBitWidth() ? T1 : T2; |
| 3788 | } |
| 3789 | |
| 3790 | static Type *largestIntegerVectorType(Type *T1, Type *T2) { |
| 3791 | auto *I1 = cast<IntegerType>(cast<VectorType>(T1)->getElementType()); |
| 3792 | auto *I2 = cast<IntegerType>(cast<VectorType>(T2)->getElementType()); |
| 3793 | return I1->getBitWidth() > I2->getBitWidth() ? T1 : T2; |
| 3794 | } |
| 3795 | |
| 3796 | void InnerLoopVectorizer::truncateToMinimalBitwidths(VPTransformState &State) { |
| 3797 | // For every instruction `I` in MinBWs, truncate the operands, create a |
| 3798 | // truncated version of `I` and reextend its result. InstCombine runs |
| 3799 | // later and will remove any ext/trunc pairs. |
| 3800 | SmallPtrSet<Value *, 4> Erased; |
| 3801 | for (const auto &KV : Cost->getMinimalBitwidths()) { |
| 3802 | // If the value wasn't vectorized, we must maintain the original scalar |
| 3803 | // type. The absence of the value from State indicates that it |
| 3804 | // wasn't vectorized. |
| 3805 | // FIXME: Should not rely on getVPValue at this point. |
| 3806 | VPValue *Def = State.Plan->getVPValue(KV.first, true); |
| 3807 | if (!State.hasAnyVectorValue(Def)) |
| 3808 | continue; |
| 3809 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 3810 | Value *I = State.get(Def, Part); |
| 3811 | if (Erased.count(I) || I->use_empty() || !isa<Instruction>(I)) |
| 3812 | continue; |
| 3813 | Type *OriginalTy = I->getType(); |
| 3814 | Type *ScalarTruncatedTy = |
| 3815 | IntegerType::get(OriginalTy->getContext(), KV.second); |
| 3816 | auto *TruncatedTy = VectorType::get( |
| 3817 | ScalarTruncatedTy, cast<VectorType>(OriginalTy)->getElementCount()); |
| 3818 | if (TruncatedTy == OriginalTy) |
| 3819 | continue; |
| 3820 | |
| 3821 | IRBuilder<> B(cast<Instruction>(I)); |
| 3822 | auto ShrinkOperand = [&](Value *V) -> Value * { |
| 3823 | if (auto *ZI = dyn_cast<ZExtInst>(V)) |
| 3824 | if (ZI->getSrcTy() == TruncatedTy) |
| 3825 | return ZI->getOperand(0); |
| 3826 | return B.CreateZExtOrTrunc(V, TruncatedTy); |
| 3827 | }; |
| 3828 | |
| 3829 | // The actual instruction modification depends on the instruction type, |
| 3830 | // unfortunately. |
| 3831 | Value *NewI = nullptr; |
| 3832 | if (auto *BO = dyn_cast<BinaryOperator>(I)) { |
| 3833 | NewI = B.CreateBinOp(BO->getOpcode(), ShrinkOperand(BO->getOperand(0)), |
| 3834 | ShrinkOperand(BO->getOperand(1))); |
| 3835 | |
| 3836 | // Any wrapping introduced by shrinking this operation shouldn't be |
| 3837 | // considered undefined behavior. So, we can't unconditionally copy |
| 3838 | // arithmetic wrapping flags to NewI. |
| 3839 | cast<BinaryOperator>(NewI)->copyIRFlags(I, /*IncludeWrapFlags=*/false); |
| 3840 | } else if (auto *CI = dyn_cast<ICmpInst>(I)) { |
| 3841 | NewI = |
| 3842 | B.CreateICmp(CI->getPredicate(), ShrinkOperand(CI->getOperand(0)), |
| 3843 | ShrinkOperand(CI->getOperand(1))); |
| 3844 | } else if (auto *SI = dyn_cast<SelectInst>(I)) { |
| 3845 | NewI = B.CreateSelect(SI->getCondition(), |
| 3846 | ShrinkOperand(SI->getTrueValue()), |
| 3847 | ShrinkOperand(SI->getFalseValue())); |
| 3848 | } else if (auto *CI = dyn_cast<CastInst>(I)) { |
| 3849 | switch (CI->getOpcode()) { |
| 3850 | default: |
| 3851 | llvm_unreachable("Unhandled cast!")::llvm::llvm_unreachable_internal("Unhandled cast!", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 3851); |
| 3852 | case Instruction::Trunc: |
| 3853 | NewI = ShrinkOperand(CI->getOperand(0)); |
| 3854 | break; |
| 3855 | case Instruction::SExt: |
| 3856 | NewI = B.CreateSExtOrTrunc( |
| 3857 | CI->getOperand(0), |
| 3858 | smallestIntegerVectorType(OriginalTy, TruncatedTy)); |
| 3859 | break; |
| 3860 | case Instruction::ZExt: |
| 3861 | NewI = B.CreateZExtOrTrunc( |
| 3862 | CI->getOperand(0), |
| 3863 | smallestIntegerVectorType(OriginalTy, TruncatedTy)); |
| 3864 | break; |
| 3865 | } |
| 3866 | } else if (auto *SI = dyn_cast<ShuffleVectorInst>(I)) { |
| 3867 | auto Elements0 = |
| 3868 | cast<VectorType>(SI->getOperand(0)->getType())->getElementCount(); |
| 3869 | auto *O0 = B.CreateZExtOrTrunc( |
| 3870 | SI->getOperand(0), VectorType::get(ScalarTruncatedTy, Elements0)); |
| 3871 | auto Elements1 = |
| 3872 | cast<VectorType>(SI->getOperand(1)->getType())->getElementCount(); |
| 3873 | auto *O1 = B.CreateZExtOrTrunc( |
| 3874 | SI->getOperand(1), VectorType::get(ScalarTruncatedTy, Elements1)); |
| 3875 | |
| 3876 | NewI = B.CreateShuffleVector(O0, O1, SI->getShuffleMask()); |
| 3877 | } else if (isa<LoadInst>(I) || isa<PHINode>(I)) { |
| 3878 | // Don't do anything with the operands, just extend the result. |
| 3879 | continue; |
| 3880 | } else if (auto *IE = dyn_cast<InsertElementInst>(I)) { |
| 3881 | auto Elements = |
| 3882 | cast<VectorType>(IE->getOperand(0)->getType())->getElementCount(); |
| 3883 | auto *O0 = B.CreateZExtOrTrunc( |
| 3884 | IE->getOperand(0), VectorType::get(ScalarTruncatedTy, Elements)); |
| 3885 | auto *O1 = B.CreateZExtOrTrunc(IE->getOperand(1), ScalarTruncatedTy); |
| 3886 | NewI = B.CreateInsertElement(O0, O1, IE->getOperand(2)); |
| 3887 | } else if (auto *EE = dyn_cast<ExtractElementInst>(I)) { |
| 3888 | auto Elements = |
| 3889 | cast<VectorType>(EE->getOperand(0)->getType())->getElementCount(); |
| 3890 | auto *O0 = B.CreateZExtOrTrunc( |
| 3891 | EE->getOperand(0), VectorType::get(ScalarTruncatedTy, Elements)); |
| 3892 | NewI = B.CreateExtractElement(O0, EE->getOperand(2)); |
| 3893 | } else { |
| 3894 | // If we don't know what to do, be conservative and don't do anything. |
| 3895 | continue; |
| 3896 | } |
| 3897 | |
| 3898 | // Lastly, extend the result. |
| 3899 | NewI->takeName(cast<Instruction>(I)); |
| 3900 | Value *Res = B.CreateZExtOrTrunc(NewI, OriginalTy); |
| 3901 | I->replaceAllUsesWith(Res); |
| 3902 | cast<Instruction>(I)->eraseFromParent(); |
| 3903 | Erased.insert(I); |
| 3904 | State.reset(Def, Res, Part); |
| 3905 | } |
| 3906 | } |
| 3907 | |
| 3908 | // We'll have created a bunch of ZExts that are now parentless. Clean up. |
| 3909 | for (const auto &KV : Cost->getMinimalBitwidths()) { |
| 3910 | // If the value wasn't vectorized, we must maintain the original scalar |
| 3911 | // type. The absence of the value from State indicates that it |
| 3912 | // wasn't vectorized. |
| 3913 | // FIXME: Should not rely on getVPValue at this point. |
| 3914 | VPValue *Def = State.Plan->getVPValue(KV.first, true); |
| 3915 | if (!State.hasAnyVectorValue(Def)) |
| 3916 | continue; |
| 3917 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 3918 | Value *I = State.get(Def, Part); |
| 3919 | ZExtInst *Inst = dyn_cast<ZExtInst>(I); |
| 3920 | if (Inst && Inst->use_empty()) { |
| 3921 | Value *NewI = Inst->getOperand(0); |
| 3922 | Inst->eraseFromParent(); |
| 3923 | State.reset(Def, NewI, Part); |
| 3924 | } |
| 3925 | } |
| 3926 | } |
| 3927 | } |
| 3928 | |
| 3929 | void InnerLoopVectorizer::fixVectorizedLoop(VPTransformState &State) { |
| 3930 | // Insert truncates and extends for any truncated instructions as hints to |
| 3931 | // InstCombine. |
| 3932 | if (VF.isVector()) |
| 3933 | truncateToMinimalBitwidths(State); |
| 3934 | |
| 3935 | // Fix widened non-induction PHIs by setting up the PHI operands. |
| 3936 | if (OrigPHIsToFix.size()) { |
| 3937 | assert(EnableVPlanNativePath &&(static_cast <bool> (EnableVPlanNativePath && "Unexpected non-induction PHIs for fixup in non VPlan-native path" ) ? void (0) : __assert_fail ("EnableVPlanNativePath && \"Unexpected non-induction PHIs for fixup in non VPlan-native path\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3938, __extension__ __PRETTY_FUNCTION__)) |
| 3938 | "Unexpected non-induction PHIs for fixup in non VPlan-native path")(static_cast <bool> (EnableVPlanNativePath && "Unexpected non-induction PHIs for fixup in non VPlan-native path" ) ? void (0) : __assert_fail ("EnableVPlanNativePath && \"Unexpected non-induction PHIs for fixup in non VPlan-native path\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 3938, __extension__ __PRETTY_FUNCTION__)); |
| 3939 | fixNonInductionPHIs(State); |
| 3940 | } |
| 3941 | |
| 3942 | // At this point every instruction in the original loop is widened to a |
| 3943 | // vector form. Now we need to fix the recurrences in the loop. These PHI |
| 3944 | // nodes are currently empty because we did not want to introduce cycles. |
| 3945 | // This is the second stage of vectorizing recurrences. |
| 3946 | fixCrossIterationPHIs(State); |
| 3947 | |
| 3948 | // Forget the original basic block. |
| 3949 | PSE.getSE()->forgetLoop(OrigLoop); |
| 3950 | |
| 3951 | // If we inserted an edge from the middle block to the unique exit block, |
| 3952 | // update uses outside the loop (phis) to account for the newly inserted |
| 3953 | // edge. |
| 3954 | if (!Cost->requiresScalarEpilogue(VF)) { |
| 3955 | // Fix-up external users of the induction variables. |
| 3956 | for (auto &Entry : Legal->getInductionVars()) |
| 3957 | fixupIVUsers(Entry.first, Entry.second, |
| 3958 | getOrCreateVectorTripCount(LI->getLoopFor(LoopVectorBody)), |
| 3959 | IVEndValues[Entry.first], LoopMiddleBlock); |
| 3960 | |
| 3961 | fixLCSSAPHIs(State); |
| 3962 | } |
| 3963 | |
| 3964 | for (Instruction *PI : PredicatedInstructions) |
| 3965 | sinkScalarOperands(&*PI); |
| 3966 | |
| 3967 | // Remove redundant induction instructions. |
| 3968 | cse(LoopVectorBody); |
| 3969 | |
| 3970 | // Set/update profile weights for the vector and remainder loops as original |
| 3971 | // loop iterations are now distributed among them. Note that original loop |
| 3972 | // represented by LoopScalarBody becomes remainder loop after vectorization. |
| 3973 | // |
| 3974 | // For cases like foldTailByMasking() and requiresScalarEpiloque() we may |
| 3975 | // end up getting slightly roughened result but that should be OK since |
| 3976 | // profile is not inherently precise anyway. Note also possible bypass of |
| 3977 | // vector code caused by legality checks is ignored, assigning all the weight |
| 3978 | // to the vector loop, optimistically. |
| 3979 | // |
| 3980 | // For scalable vectorization we can't know at compile time how many iterations |
| 3981 | // of the loop are handled in one vector iteration, so instead assume a pessimistic |
| 3982 | // vscale of '1'. |
| 3983 | setProfileInfoAfterUnrolling( |
| 3984 | LI->getLoopFor(LoopScalarBody), LI->getLoopFor(LoopVectorBody), |
| 3985 | LI->getLoopFor(LoopScalarBody), VF.getKnownMinValue() * UF); |
| 3986 | } |
| 3987 | |
| 3988 | void InnerLoopVectorizer::fixCrossIterationPHIs(VPTransformState &State) { |
| 3989 | // In order to support recurrences we need to be able to vectorize Phi nodes. |
| 3990 | // Phi nodes have cycles, so we need to vectorize them in two stages. This is |
| 3991 | // stage #2: We now need to fix the recurrences by adding incoming edges to |
| 3992 | // the currently empty PHI nodes. At this point every instruction in the |
| 3993 | // original loop is widened to a vector form so we can use them to construct |
| 3994 | // the incoming edges. |
| 3995 | VPBasicBlock *Header = State.Plan->getEntry()->getEntryBasicBlock(); |
| 3996 | for (VPRecipeBase &R : Header->phis()) { |
| 3997 | if (auto *ReductionPhi = dyn_cast<VPReductionPHIRecipe>(&R)) |
| 3998 | fixReduction(ReductionPhi, State); |
| 3999 | else if (auto *FOR = dyn_cast<VPFirstOrderRecurrencePHIRecipe>(&R)) |
| 4000 | fixFirstOrderRecurrence(FOR, State); |
| 4001 | } |
| 4002 | } |
| 4003 | |
| 4004 | void InnerLoopVectorizer::fixFirstOrderRecurrence( |
| 4005 | VPFirstOrderRecurrencePHIRecipe *PhiR, VPTransformState &State) { |
| 4006 | // This is the second phase of vectorizing first-order recurrences. An |
| 4007 | // overview of the transformation is described below. Suppose we have the |
| 4008 | // following loop. |
| 4009 | // |
| 4010 | // for (int i = 0; i < n; ++i) |
| 4011 | // b[i] = a[i] - a[i - 1]; |
| 4012 | // |
| 4013 | // There is a first-order recurrence on "a". For this loop, the shorthand |
| 4014 | // scalar IR looks like: |
| 4015 | // |
| 4016 | // scalar.ph: |
| 4017 | // s_init = a[-1] |
| 4018 | // br scalar.body |
| 4019 | // |
| 4020 | // scalar.body: |
| 4021 | // i = phi [0, scalar.ph], [i+1, scalar.body] |
| 4022 | // s1 = phi [s_init, scalar.ph], [s2, scalar.body] |
| 4023 | // s2 = a[i] |
| 4024 | // b[i] = s2 - s1 |
| 4025 | // br cond, scalar.body, ... |
| 4026 | // |
| 4027 | // In this example, s1 is a recurrence because it's value depends on the |
| 4028 | // previous iteration. In the first phase of vectorization, we created a |
| 4029 | // vector phi v1 for s1. We now complete the vectorization and produce the |
| 4030 | // shorthand vector IR shown below (for VF = 4, UF = 1). |
| 4031 | // |
| 4032 | // vector.ph: |
| 4033 | // v_init = vector(..., ..., ..., a[-1]) |
| 4034 | // br vector.body |
| 4035 | // |
| 4036 | // vector.body |
| 4037 | // i = phi [0, vector.ph], [i+4, vector.body] |
| 4038 | // v1 = phi [v_init, vector.ph], [v2, vector.body] |
| 4039 | // v2 = a[i, i+1, i+2, i+3]; |
| 4040 | // v3 = vector(v1(3), v2(0, 1, 2)) |
| 4041 | // b[i, i+1, i+2, i+3] = v2 - v3 |
| 4042 | // br cond, vector.body, middle.block |
| 4043 | // |
| 4044 | // middle.block: |
| 4045 | // x = v2(3) |
| 4046 | // br scalar.ph |
| 4047 | // |
| 4048 | // scalar.ph: |
| 4049 | // s_init = phi [x, middle.block], [a[-1], otherwise] |
| 4050 | // br scalar.body |
| 4051 | // |
| 4052 | // After execution completes the vector loop, we extract the next value of |
| 4053 | // the recurrence (x) to use as the initial value in the scalar loop. |
| 4054 | |
| 4055 | // Extract the last vector element in the middle block. This will be the |
| 4056 | // initial value for the recurrence when jumping to the scalar loop. |
| 4057 | VPValue *PreviousDef = PhiR->getBackedgeValue(); |
| 4058 | Value *Incoming = State.get(PreviousDef, UF - 1); |
| 4059 | auto *ExtractForScalar = Incoming; |
| 4060 | auto *IdxTy = Builder.getInt32Ty(); |
| 4061 | if (VF.isVector()) { |
| 4062 | auto *One = ConstantInt::get(IdxTy, 1); |
| 4063 | Builder.SetInsertPoint(LoopMiddleBlock->getTerminator()); |
| 4064 | auto *RuntimeVF = getRuntimeVF(Builder, IdxTy, VF); |
| 4065 | auto *LastIdx = Builder.CreateSub(RuntimeVF, One); |
| 4066 | ExtractForScalar = Builder.CreateExtractElement(ExtractForScalar, LastIdx, |
| 4067 | "vector.recur.extract"); |
| 4068 | } |
| 4069 | // Extract the second last element in the middle block if the |
| 4070 | // Phi is used outside the loop. We need to extract the phi itself |
| 4071 | // and not the last element (the phi update in the current iteration). This |
| 4072 | // will be the value when jumping to the exit block from the LoopMiddleBlock, |
| 4073 | // when the scalar loop is not run at all. |
| 4074 | Value *ExtractForPhiUsedOutsideLoop = nullptr; |
| 4075 | if (VF.isVector()) { |
| 4076 | auto *RuntimeVF = getRuntimeVF(Builder, IdxTy, VF); |
| 4077 | auto *Idx = Builder.CreateSub(RuntimeVF, ConstantInt::get(IdxTy, 2)); |
| 4078 | ExtractForPhiUsedOutsideLoop = Builder.CreateExtractElement( |
| 4079 | Incoming, Idx, "vector.recur.extract.for.phi"); |
| 4080 | } else if (UF > 1) |
| 4081 | // When loop is unrolled without vectorizing, initialize |
| 4082 | // ExtractForPhiUsedOutsideLoop with the value just prior to unrolled value |
| 4083 | // of `Incoming`. This is analogous to the vectorized case above: extracting |
| 4084 | // the second last element when VF > 1. |
| 4085 | ExtractForPhiUsedOutsideLoop = State.get(PreviousDef, UF - 2); |
| 4086 | |
| 4087 | // Fix the initial value of the original recurrence in the scalar loop. |
| 4088 | Builder.SetInsertPoint(&*LoopScalarPreHeader->begin()); |
| 4089 | PHINode *Phi = cast<PHINode>(PhiR->getUnderlyingValue()); |
| 4090 | auto *Start = Builder.CreatePHI(Phi->getType(), 2, "scalar.recur.init"); |
| 4091 | auto *ScalarInit = PhiR->getStartValue()->getLiveInIRValue(); |
| 4092 | for (auto *BB : predecessors(LoopScalarPreHeader)) { |
| 4093 | auto *Incoming = BB == LoopMiddleBlock ? ExtractForScalar : ScalarInit; |
| 4094 | Start->addIncoming(Incoming, BB); |
| 4095 | } |
| 4096 | |
| 4097 | Phi->setIncomingValueForBlock(LoopScalarPreHeader, Start); |
| 4098 | Phi->setName("scalar.recur"); |
| 4099 | |
| 4100 | // Finally, fix users of the recurrence outside the loop. The users will need |
| 4101 | // either the last value of the scalar recurrence or the last value of the |
| 4102 | // vector recurrence we extracted in the middle block. Since the loop is in |
| 4103 | // LCSSA form, we just need to find all the phi nodes for the original scalar |
| 4104 | // recurrence in the exit block, and then add an edge for the middle block. |
| 4105 | // Note that LCSSA does not imply single entry when the original scalar loop |
| 4106 | // had multiple exiting edges (as we always run the last iteration in the |
| 4107 | // scalar epilogue); in that case, there is no edge from middle to exit and |
| 4108 | // and thus no phis which needed updated. |
| 4109 | if (!Cost->requiresScalarEpilogue(VF)) |
| 4110 | for (PHINode &LCSSAPhi : LoopExitBlock->phis()) |
| 4111 | if (llvm::is_contained(LCSSAPhi.incoming_values(), Phi)) |
| 4112 | LCSSAPhi.addIncoming(ExtractForPhiUsedOutsideLoop, LoopMiddleBlock); |
| 4113 | } |
| 4114 | |
| 4115 | void InnerLoopVectorizer::fixReduction(VPReductionPHIRecipe *PhiR, |
| 4116 | VPTransformState &State) { |
| 4117 | PHINode *OrigPhi = cast<PHINode>(PhiR->getUnderlyingValue()); |
| 4118 | // Get it's reduction variable descriptor. |
| 4119 | assert(Legal->isReductionVariable(OrigPhi) &&(static_cast <bool> (Legal->isReductionVariable(OrigPhi ) && "Unable to find the reduction variable") ? void ( 0) : __assert_fail ("Legal->isReductionVariable(OrigPhi) && \"Unable to find the reduction variable\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4120, __extension__ __PRETTY_FUNCTION__)) |
| 4120 | "Unable to find the reduction variable")(static_cast <bool> (Legal->isReductionVariable(OrigPhi ) && "Unable to find the reduction variable") ? void ( 0) : __assert_fail ("Legal->isReductionVariable(OrigPhi) && \"Unable to find the reduction variable\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4120, __extension__ __PRETTY_FUNCTION__)); |
| 4121 | const RecurrenceDescriptor &RdxDesc = PhiR->getRecurrenceDescriptor(); |
| 4122 | |
| 4123 | RecurKind RK = RdxDesc.getRecurrenceKind(); |
| 4124 | TrackingVH<Value> ReductionStartValue = RdxDesc.getRecurrenceStartValue(); |
| 4125 | Instruction *LoopExitInst = RdxDesc.getLoopExitInstr(); |
| 4126 | setDebugLocFromInst(ReductionStartValue); |
| 4127 | |
| 4128 | VPValue *LoopExitInstDef = PhiR->getBackedgeValue(); |
| 4129 | // This is the vector-clone of the value that leaves the loop. |
| 4130 | Type *VecTy = State.get(LoopExitInstDef, 0)->getType(); |
| 4131 | |
| 4132 | // Wrap flags are in general invalid after vectorization, clear them. |
| 4133 | clearReductionWrapFlags(RdxDesc, State); |
| 4134 | |
| 4135 | // Before each round, move the insertion point right between |
| 4136 | // the PHIs and the values we are going to write. |
| 4137 | // This allows us to write both PHINodes and the extractelement |
| 4138 | // instructions. |
| 4139 | Builder.SetInsertPoint(&*LoopMiddleBlock->getFirstInsertionPt()); |
| 4140 | |
| 4141 | setDebugLocFromInst(LoopExitInst); |
| 4142 | |
| 4143 | Type *PhiTy = OrigPhi->getType(); |
| 4144 | // If tail is folded by masking, the vector value to leave the loop should be |
| 4145 | // a Select choosing between the vectorized LoopExitInst and vectorized Phi, |
| 4146 | // instead of the former. For an inloop reduction the reduction will already |
| 4147 | // be predicated, and does not need to be handled here. |
| 4148 | if (Cost->foldTailByMasking() && !PhiR->isInLoop()) { |
| 4149 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 4150 | Value *VecLoopExitInst = State.get(LoopExitInstDef, Part); |
| 4151 | Value *Sel = nullptr; |
| 4152 | for (User *U : VecLoopExitInst->users()) { |
| 4153 | if (isa<SelectInst>(U)) { |
| 4154 | assert(!Sel && "Reduction exit feeding two selects")(static_cast <bool> (!Sel && "Reduction exit feeding two selects" ) ? void (0) : __assert_fail ("!Sel && \"Reduction exit feeding two selects\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4154, __extension__ __PRETTY_FUNCTION__)); |
| 4155 | Sel = U; |
| 4156 | } else |
| 4157 | assert(isa<PHINode>(U) && "Reduction exit must feed Phi's or select")(static_cast <bool> (isa<PHINode>(U) && "Reduction exit must feed Phi's or select" ) ? void (0) : __assert_fail ("isa<PHINode>(U) && \"Reduction exit must feed Phi's or select\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4157, __extension__ __PRETTY_FUNCTION__)); |
| 4158 | } |
| 4159 | assert(Sel && "Reduction exit feeds no select")(static_cast <bool> (Sel && "Reduction exit feeds no select" ) ? void (0) : __assert_fail ("Sel && \"Reduction exit feeds no select\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4159, __extension__ __PRETTY_FUNCTION__)); |
| 4160 | State.reset(LoopExitInstDef, Sel, Part); |
| 4161 | |
| 4162 | // If the target can create a predicated operator for the reduction at no |
| 4163 | // extra cost in the loop (for example a predicated vadd), it can be |
| 4164 | // cheaper for the select to remain in the loop than be sunk out of it, |
| 4165 | // and so use the select value for the phi instead of the old |
| 4166 | // LoopExitValue. |
| 4167 | if (PreferPredicatedReductionSelect || |
| 4168 | TTI->preferPredicatedReductionSelect( |
| 4169 | RdxDesc.getOpcode(), PhiTy, |
| 4170 | TargetTransformInfo::ReductionFlags())) { |
| 4171 | auto *VecRdxPhi = |
| 4172 | cast<PHINode>(State.get(PhiR, Part)); |
| 4173 | VecRdxPhi->setIncomingValueForBlock( |
| 4174 | LI->getLoopFor(LoopVectorBody)->getLoopLatch(), Sel); |
| 4175 | } |
| 4176 | } |
| 4177 | } |
| 4178 | |
| 4179 | // If the vector reduction can be performed in a smaller type, we truncate |
| 4180 | // then extend the loop exit value to enable InstCombine to evaluate the |
| 4181 | // entire expression in the smaller type. |
| 4182 | if (VF.isVector() && PhiTy != RdxDesc.getRecurrenceType()) { |
| 4183 | assert(!PhiR->isInLoop() && "Unexpected truncated inloop reduction!")(static_cast <bool> (!PhiR->isInLoop() && "Unexpected truncated inloop reduction!" ) ? void (0) : __assert_fail ("!PhiR->isInLoop() && \"Unexpected truncated inloop reduction!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4183, __extension__ __PRETTY_FUNCTION__)); |
| 4184 | Type *RdxVecTy = VectorType::get(RdxDesc.getRecurrenceType(), VF); |
| 4185 | Builder.SetInsertPoint( |
| 4186 | LI->getLoopFor(LoopVectorBody)->getLoopLatch()->getTerminator()); |
| 4187 | VectorParts RdxParts(UF); |
| 4188 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 4189 | RdxParts[Part] = State.get(LoopExitInstDef, Part); |
| 4190 | Value *Trunc = Builder.CreateTrunc(RdxParts[Part], RdxVecTy); |
| 4191 | Value *Extnd = RdxDesc.isSigned() ? Builder.CreateSExt(Trunc, VecTy) |
| 4192 | : Builder.CreateZExt(Trunc, VecTy); |
| 4193 | for (User *U : llvm::make_early_inc_range(RdxParts[Part]->users())) |
| 4194 | if (U != Trunc) { |
| 4195 | U->replaceUsesOfWith(RdxParts[Part], Extnd); |
| 4196 | RdxParts[Part] = Extnd; |
| 4197 | } |
| 4198 | } |
| 4199 | Builder.SetInsertPoint(&*LoopMiddleBlock->getFirstInsertionPt()); |
| 4200 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 4201 | RdxParts[Part] = Builder.CreateTrunc(RdxParts[Part], RdxVecTy); |
| 4202 | State.reset(LoopExitInstDef, RdxParts[Part], Part); |
| 4203 | } |
| 4204 | } |
| 4205 | |
| 4206 | // Reduce all of the unrolled parts into a single vector. |
| 4207 | Value *ReducedPartRdx = State.get(LoopExitInstDef, 0); |
| 4208 | unsigned Op = RecurrenceDescriptor::getOpcode(RK); |
| 4209 | |
| 4210 | // The middle block terminator has already been assigned a DebugLoc here (the |
| 4211 | // OrigLoop's single latch terminator). We want the whole middle block to |
| 4212 | // appear to execute on this line because: (a) it is all compiler generated, |
| 4213 | // (b) these instructions are always executed after evaluating the latch |
| 4214 | // conditional branch, and (c) other passes may add new predecessors which |
| 4215 | // terminate on this line. This is the easiest way to ensure we don't |
| 4216 | // accidentally cause an extra step back into the loop while debugging. |
| 4217 | setDebugLocFromInst(LoopMiddleBlock->getTerminator()); |
| 4218 | if (PhiR->isOrdered()) |
| 4219 | ReducedPartRdx = State.get(LoopExitInstDef, UF - 1); |
| 4220 | else { |
| 4221 | // Floating-point operations should have some FMF to enable the reduction. |
| 4222 | IRBuilderBase::FastMathFlagGuard FMFG(Builder); |
| 4223 | Builder.setFastMathFlags(RdxDesc.getFastMathFlags()); |
| 4224 | for (unsigned Part = 1; Part < UF; ++Part) { |
| 4225 | Value *RdxPart = State.get(LoopExitInstDef, Part); |
| 4226 | if (Op != Instruction::ICmp && Op != Instruction::FCmp) { |
| 4227 | ReducedPartRdx = Builder.CreateBinOp( |
| 4228 | (Instruction::BinaryOps)Op, RdxPart, ReducedPartRdx, "bin.rdx"); |
| 4229 | } else if (RecurrenceDescriptor::isSelectCmpRecurrenceKind(RK)) |
| 4230 | ReducedPartRdx = createSelectCmpOp(Builder, ReductionStartValue, RK, |
| 4231 | ReducedPartRdx, RdxPart); |
| 4232 | else |
| 4233 | ReducedPartRdx = createMinMaxOp(Builder, RK, ReducedPartRdx, RdxPart); |
| 4234 | } |
| 4235 | } |
| 4236 | |
| 4237 | // Create the reduction after the loop. Note that inloop reductions create the |
| 4238 | // target reduction in the loop using a Reduction recipe. |
| 4239 | if (VF.isVector() && !PhiR->isInLoop()) { |
| 4240 | ReducedPartRdx = |
| 4241 | createTargetReduction(Builder, TTI, RdxDesc, ReducedPartRdx, OrigPhi); |
| 4242 | // If the reduction can be performed in a smaller type, we need to extend |
| 4243 | // the reduction to the wider type before we branch to the original loop. |
| 4244 | if (PhiTy != RdxDesc.getRecurrenceType()) |
| 4245 | ReducedPartRdx = RdxDesc.isSigned() |
| 4246 | ? Builder.CreateSExt(ReducedPartRdx, PhiTy) |
| 4247 | : Builder.CreateZExt(ReducedPartRdx, PhiTy); |
| 4248 | } |
| 4249 | |
| 4250 | PHINode *ResumePhi = |
| 4251 | dyn_cast<PHINode>(PhiR->getStartValue()->getUnderlyingValue()); |
| 4252 | |
| 4253 | // Create a phi node that merges control-flow from the backedge-taken check |
| 4254 | // block and the middle block. |
| 4255 | PHINode *BCBlockPhi = PHINode::Create(PhiTy, 2, "bc.merge.rdx", |
| 4256 | LoopScalarPreHeader->getTerminator()); |
| 4257 | |
| 4258 | // If we are fixing reductions in the epilogue loop then we should already |
| 4259 | // have created a bc.merge.rdx Phi after the main vector body. Ensure that |
| 4260 | // we carry over the incoming values correctly. |
| 4261 | for (auto *Incoming : predecessors(LoopScalarPreHeader)) { |
| 4262 | if (Incoming == LoopMiddleBlock) |
| 4263 | BCBlockPhi->addIncoming(ReducedPartRdx, Incoming); |
| 4264 | else if (ResumePhi && llvm::is_contained(ResumePhi->blocks(), Incoming)) |
| 4265 | BCBlockPhi->addIncoming(ResumePhi->getIncomingValueForBlock(Incoming), |
| 4266 | Incoming); |
| 4267 | else |
| 4268 | BCBlockPhi->addIncoming(ReductionStartValue, Incoming); |
| 4269 | } |
| 4270 | |
| 4271 | // Set the resume value for this reduction |
| 4272 | ReductionResumeValues.insert({&RdxDesc, BCBlockPhi}); |
| 4273 | |
| 4274 | // Now, we need to fix the users of the reduction variable |
| 4275 | // inside and outside of the scalar remainder loop. |
| 4276 | |
| 4277 | // We know that the loop is in LCSSA form. We need to update the PHI nodes |
| 4278 | // in the exit blocks. See comment on analogous loop in |
| 4279 | // fixFirstOrderRecurrence for a more complete explaination of the logic. |
| 4280 | if (!Cost->requiresScalarEpilogue(VF)) |
| 4281 | for (PHINode &LCSSAPhi : LoopExitBlock->phis()) |
| 4282 | if (llvm::is_contained(LCSSAPhi.incoming_values(), LoopExitInst)) |
| 4283 | LCSSAPhi.addIncoming(ReducedPartRdx, LoopMiddleBlock); |
| 4284 | |
| 4285 | // Fix the scalar loop reduction variable with the incoming reduction sum |
| 4286 | // from the vector body and from the backedge value. |
| 4287 | int IncomingEdgeBlockIdx = |
| 4288 | OrigPhi->getBasicBlockIndex(OrigLoop->getLoopLatch()); |
| 4289 | assert(IncomingEdgeBlockIdx >= 0 && "Invalid block index")(static_cast <bool> (IncomingEdgeBlockIdx >= 0 && "Invalid block index") ? void (0) : __assert_fail ("IncomingEdgeBlockIdx >= 0 && \"Invalid block index\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4289, __extension__ __PRETTY_FUNCTION__)); |
| 4290 | // Pick the other block. |
| 4291 | int SelfEdgeBlockIdx = (IncomingEdgeBlockIdx ? 0 : 1); |
| 4292 | OrigPhi->setIncomingValue(SelfEdgeBlockIdx, BCBlockPhi); |
| 4293 | OrigPhi->setIncomingValue(IncomingEdgeBlockIdx, LoopExitInst); |
| 4294 | } |
| 4295 | |
| 4296 | void InnerLoopVectorizer::clearReductionWrapFlags(const RecurrenceDescriptor &RdxDesc, |
| 4297 | VPTransformState &State) { |
| 4298 | RecurKind RK = RdxDesc.getRecurrenceKind(); |
| 4299 | if (RK != RecurKind::Add && RK != RecurKind::Mul) |
| 4300 | return; |
| 4301 | |
| 4302 | Instruction *LoopExitInstr = RdxDesc.getLoopExitInstr(); |
| 4303 | assert(LoopExitInstr && "null loop exit instruction")(static_cast <bool> (LoopExitInstr && "null loop exit instruction" ) ? void (0) : __assert_fail ("LoopExitInstr && \"null loop exit instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4303, __extension__ __PRETTY_FUNCTION__)); |
| 4304 | SmallVector<Instruction *, 8> Worklist; |
| 4305 | SmallPtrSet<Instruction *, 8> Visited; |
| 4306 | Worklist.push_back(LoopExitInstr); |
| 4307 | Visited.insert(LoopExitInstr); |
| 4308 | |
| 4309 | while (!Worklist.empty()) { |
| 4310 | Instruction *Cur = Worklist.pop_back_val(); |
| 4311 | if (isa<OverflowingBinaryOperator>(Cur)) |
| 4312 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 4313 | // FIXME: Should not rely on getVPValue at this point. |
| 4314 | Value *V = State.get(State.Plan->getVPValue(Cur, true), Part); |
| 4315 | cast<Instruction>(V)->dropPoisonGeneratingFlags(); |
| 4316 | } |
| 4317 | |
| 4318 | for (User *U : Cur->users()) { |
| 4319 | Instruction *UI = cast<Instruction>(U); |
| 4320 | if ((Cur != LoopExitInstr || OrigLoop->contains(UI->getParent())) && |
| 4321 | Visited.insert(UI).second) |
| 4322 | Worklist.push_back(UI); |
| 4323 | } |
| 4324 | } |
| 4325 | } |
| 4326 | |
| 4327 | void InnerLoopVectorizer::fixLCSSAPHIs(VPTransformState &State) { |
| 4328 | for (PHINode &LCSSAPhi : LoopExitBlock->phis()) { |
| 4329 | if (LCSSAPhi.getBasicBlockIndex(LoopMiddleBlock) != -1) |
| 4330 | // Some phis were already hand updated by the reduction and recurrence |
| 4331 | // code above, leave them alone. |
| 4332 | continue; |
| 4333 | |
| 4334 | auto *IncomingValue = LCSSAPhi.getIncomingValue(0); |
| 4335 | // Non-instruction incoming values will have only one value. |
| 4336 | |
| 4337 | VPLane Lane = VPLane::getFirstLane(); |
| 4338 | if (isa<Instruction>(IncomingValue) && |
| 4339 | !Cost->isUniformAfterVectorization(cast<Instruction>(IncomingValue), |
| 4340 | VF)) |
| 4341 | Lane = VPLane::getLastLaneForVF(VF); |
| 4342 | |
| 4343 | // Can be a loop invariant incoming value or the last scalar value to be |
| 4344 | // extracted from the vectorized loop. |
| 4345 | // FIXME: Should not rely on getVPValue at this point. |
| 4346 | Builder.SetInsertPoint(LoopMiddleBlock->getTerminator()); |
| 4347 | Value *lastIncomingValue = |
| 4348 | OrigLoop->isLoopInvariant(IncomingValue) |
| 4349 | ? IncomingValue |
| 4350 | : State.get(State.Plan->getVPValue(IncomingValue, true), |
| 4351 | VPIteration(UF - 1, Lane)); |
| 4352 | LCSSAPhi.addIncoming(lastIncomingValue, LoopMiddleBlock); |
| 4353 | } |
| 4354 | } |
| 4355 | |
| 4356 | void InnerLoopVectorizer::sinkScalarOperands(Instruction *PredInst) { |
| 4357 | // The basic block and loop containing the predicated instruction. |
| 4358 | auto *PredBB = PredInst->getParent(); |
| 4359 | auto *VectorLoop = LI->getLoopFor(PredBB); |
| 4360 | |
| 4361 | // Initialize a worklist with the operands of the predicated instruction. |
| 4362 | SetVector<Value *> Worklist(PredInst->op_begin(), PredInst->op_end()); |
| 4363 | |
| 4364 | // Holds instructions that we need to analyze again. An instruction may be |
| 4365 | // reanalyzed if we don't yet know if we can sink it or not. |
| 4366 | SmallVector<Instruction *, 8> InstsToReanalyze; |
| 4367 | |
| 4368 | // Returns true if a given use occurs in the predicated block. Phi nodes use |
| 4369 | // their operands in their corresponding predecessor blocks. |
| 4370 | auto isBlockOfUsePredicated = [&](Use &U) -> bool { |
| 4371 | auto *I = cast<Instruction>(U.getUser()); |
| 4372 | BasicBlock *BB = I->getParent(); |
| 4373 | if (auto *Phi = dyn_cast<PHINode>(I)) |
| 4374 | BB = Phi->getIncomingBlock( |
| 4375 | PHINode::getIncomingValueNumForOperand(U.getOperandNo())); |
| 4376 | return BB == PredBB; |
| 4377 | }; |
| 4378 | |
| 4379 | // Iteratively sink the scalarized operands of the predicated instruction |
| 4380 | // into the block we created for it. When an instruction is sunk, it's |
| 4381 | // operands are then added to the worklist. The algorithm ends after one pass |
| 4382 | // through the worklist doesn't sink a single instruction. |
| 4383 | bool Changed; |
| 4384 | do { |
| 4385 | // Add the instructions that need to be reanalyzed to the worklist, and |
| 4386 | // reset the changed indicator. |
| 4387 | Worklist.insert(InstsToReanalyze.begin(), InstsToReanalyze.end()); |
| 4388 | InstsToReanalyze.clear(); |
| 4389 | Changed = false; |
| 4390 | |
| 4391 | while (!Worklist.empty()) { |
| 4392 | auto *I = dyn_cast<Instruction>(Worklist.pop_back_val()); |
| 4393 | |
| 4394 | // We can't sink an instruction if it is a phi node, is not in the loop, |
| 4395 | // or may have side effects. |
| 4396 | if (!I || isa<PHINode>(I) || !VectorLoop->contains(I) || |
| 4397 | I->mayHaveSideEffects()) |
| 4398 | continue; |
| 4399 | |
| 4400 | // If the instruction is already in PredBB, check if we can sink its |
| 4401 | // operands. In that case, VPlan's sinkScalarOperands() succeeded in |
| 4402 | // sinking the scalar instruction I, hence it appears in PredBB; but it |
| 4403 | // may have failed to sink I's operands (recursively), which we try |
| 4404 | // (again) here. |
| 4405 | if (I->getParent() == PredBB) { |
| 4406 | Worklist.insert(I->op_begin(), I->op_end()); |
| 4407 | continue; |
| 4408 | } |
| 4409 | |
| 4410 | // It's legal to sink the instruction if all its uses occur in the |
| 4411 | // predicated block. Otherwise, there's nothing to do yet, and we may |
| 4412 | // need to reanalyze the instruction. |
| 4413 | if (!llvm::all_of(I->uses(), isBlockOfUsePredicated)) { |
| 4414 | InstsToReanalyze.push_back(I); |
| 4415 | continue; |
| 4416 | } |
| 4417 | |
| 4418 | // Move the instruction to the beginning of the predicated block, and add |
| 4419 | // it's operands to the worklist. |
| 4420 | I->moveBefore(&*PredBB->getFirstInsertionPt()); |
| 4421 | Worklist.insert(I->op_begin(), I->op_end()); |
| 4422 | |
| 4423 | // The sinking may have enabled other instructions to be sunk, so we will |
| 4424 | // need to iterate. |
| 4425 | Changed = true; |
| 4426 | } |
| 4427 | } while (Changed); |
| 4428 | } |
| 4429 | |
| 4430 | void InnerLoopVectorizer::fixNonInductionPHIs(VPTransformState &State) { |
| 4431 | for (PHINode *OrigPhi : OrigPHIsToFix) { |
| 4432 | VPWidenPHIRecipe *VPPhi = |
| 4433 | cast<VPWidenPHIRecipe>(State.Plan->getVPValue(OrigPhi)); |
| 4434 | PHINode *NewPhi = cast<PHINode>(State.get(VPPhi, 0)); |
| 4435 | // Make sure the builder has a valid insert point. |
| 4436 | Builder.SetInsertPoint(NewPhi); |
| 4437 | for (unsigned i = 0; i < VPPhi->getNumOperands(); ++i) { |
| 4438 | VPValue *Inc = VPPhi->getIncomingValue(i); |
| 4439 | VPBasicBlock *VPBB = VPPhi->getIncomingBlock(i); |
| 4440 | NewPhi->addIncoming(State.get(Inc, 0), State.CFG.VPBB2IRBB[VPBB]); |
| 4441 | } |
| 4442 | } |
| 4443 | } |
| 4444 | |
| 4445 | bool InnerLoopVectorizer::useOrderedReductions( |
| 4446 | const RecurrenceDescriptor &RdxDesc) { |
| 4447 | return Cost->useOrderedReductions(RdxDesc); |
| 4448 | } |
| 4449 | |
| 4450 | void InnerLoopVectorizer::widenPHIInstruction(Instruction *PN, |
| 4451 | VPWidenPHIRecipe *PhiR, |
| 4452 | VPTransformState &State) { |
| 4453 | PHINode *P = cast<PHINode>(PN); |
| 4454 | if (EnableVPlanNativePath) { |
| 4455 | // Currently we enter here in the VPlan-native path for non-induction |
| 4456 | // PHIs where all control flow is uniform. We simply widen these PHIs. |
| 4457 | // Create a vector phi with no operands - the vector phi operands will be |
| 4458 | // set at the end of vector code generation. |
| 4459 | Type *VecTy = (State.VF.isScalar()) |
| 4460 | ? PN->getType() |
| 4461 | : VectorType::get(PN->getType(), State.VF); |
| 4462 | Value *VecPhi = Builder.CreatePHI(VecTy, PN->getNumOperands(), "vec.phi"); |
| 4463 | State.set(PhiR, VecPhi, 0); |
| 4464 | OrigPHIsToFix.push_back(P); |
| 4465 | |
| 4466 | return; |
| 4467 | } |
| 4468 | |
| 4469 | assert(PN->getParent() == OrigLoop->getHeader() &&(static_cast <bool> (PN->getParent() == OrigLoop-> getHeader() && "Non-header phis should have been handled elsewhere" ) ? void (0) : __assert_fail ("PN->getParent() == OrigLoop->getHeader() && \"Non-header phis should have been handled elsewhere\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4470, __extension__ __PRETTY_FUNCTION__)) |
| 4470 | "Non-header phis should have been handled elsewhere")(static_cast <bool> (PN->getParent() == OrigLoop-> getHeader() && "Non-header phis should have been handled elsewhere" ) ? void (0) : __assert_fail ("PN->getParent() == OrigLoop->getHeader() && \"Non-header phis should have been handled elsewhere\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4470, __extension__ __PRETTY_FUNCTION__)); |
| 4471 | |
| 4472 | // In order to support recurrences we need to be able to vectorize Phi nodes. |
| 4473 | // Phi nodes have cycles, so we need to vectorize them in two stages. This is |
| 4474 | // stage #1: We create a new vector PHI node with no incoming edges. We'll use |
| 4475 | // this value when we vectorize all of the instructions that use the PHI. |
| 4476 | |
| 4477 | assert(!Legal->isReductionVariable(P) &&(static_cast <bool> (!Legal->isReductionVariable(P) && "reductions should be handled elsewhere") ? void (0) : __assert_fail ("!Legal->isReductionVariable(P) && \"reductions should be handled elsewhere\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4478, __extension__ __PRETTY_FUNCTION__)) |
| 4478 | "reductions should be handled elsewhere")(static_cast <bool> (!Legal->isReductionVariable(P) && "reductions should be handled elsewhere") ? void (0) : __assert_fail ("!Legal->isReductionVariable(P) && \"reductions should be handled elsewhere\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4478, __extension__ __PRETTY_FUNCTION__)); |
| 4479 | |
| 4480 | setDebugLocFromInst(P); |
| 4481 | |
| 4482 | // This PHINode must be an induction variable. |
| 4483 | // Make sure that we know about it. |
| 4484 | assert(Legal->getInductionVars().count(P) && "Not an induction variable")(static_cast <bool> (Legal->getInductionVars().count (P) && "Not an induction variable") ? void (0) : __assert_fail ("Legal->getInductionVars().count(P) && \"Not an induction variable\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4484, __extension__ __PRETTY_FUNCTION__)); |
| 4485 | |
| 4486 | InductionDescriptor II = Legal->getInductionVars().lookup(P); |
| 4487 | const DataLayout &DL = OrigLoop->getHeader()->getModule()->getDataLayout(); |
| 4488 | |
| 4489 | auto *IVR = PhiR->getParent()->getPlan()->getCanonicalIV(); |
| 4490 | PHINode *CanonicalIV = cast<PHINode>(State.get(IVR, 0)); |
| 4491 | |
| 4492 | // FIXME: The newly created binary instructions should contain nsw/nuw flags, |
| 4493 | // which can be found from the original scalar operations. |
| 4494 | switch (II.getKind()) { |
| 4495 | case InductionDescriptor::IK_NoInduction: |
| 4496 | llvm_unreachable("Unknown induction")::llvm::llvm_unreachable_internal("Unknown induction", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 4496); |
| 4497 | case InductionDescriptor::IK_IntInduction: |
| 4498 | case InductionDescriptor::IK_FpInduction: |
| 4499 | llvm_unreachable("Integer/fp induction is handled elsewhere.")::llvm::llvm_unreachable_internal("Integer/fp induction is handled elsewhere." , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4499); |
| 4500 | case InductionDescriptor::IK_PtrInduction: { |
| 4501 | // Handle the pointer induction variable case. |
| 4502 | assert(P->getType()->isPointerTy() && "Unexpected type.")(static_cast <bool> (P->getType()->isPointerTy() && "Unexpected type.") ? void (0) : __assert_fail ("P->getType()->isPointerTy() && \"Unexpected type.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4502, __extension__ __PRETTY_FUNCTION__)); |
| 4503 | |
| 4504 | if (Cost->isScalarAfterVectorization(P, State.VF)) { |
| 4505 | // This is the normalized GEP that starts counting at zero. |
| 4506 | Value *PtrInd = |
| 4507 | Builder.CreateSExtOrTrunc(CanonicalIV, II.getStep()->getType()); |
| 4508 | // Determine the number of scalars we need to generate for each unroll |
| 4509 | // iteration. If the instruction is uniform, we only need to generate the |
| 4510 | // first lane. Otherwise, we generate all VF values. |
| 4511 | bool IsUniform = vputils::onlyFirstLaneUsed(PhiR); |
| 4512 | assert((IsUniform || !State.VF.isScalable()) &&(static_cast <bool> ((IsUniform || !State.VF.isScalable ()) && "Cannot scalarize a scalable VF") ? void (0) : __assert_fail ("(IsUniform || !State.VF.isScalable()) && \"Cannot scalarize a scalable VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4513, __extension__ __PRETTY_FUNCTION__)) |
| 4513 | "Cannot scalarize a scalable VF")(static_cast <bool> ((IsUniform || !State.VF.isScalable ()) && "Cannot scalarize a scalable VF") ? void (0) : __assert_fail ("(IsUniform || !State.VF.isScalable()) && \"Cannot scalarize a scalable VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4513, __extension__ __PRETTY_FUNCTION__)); |
| 4514 | unsigned Lanes = IsUniform ? 1 : State.VF.getFixedValue(); |
| 4515 | |
| 4516 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 4517 | Value *PartStart = |
| 4518 | createStepForVF(Builder, PtrInd->getType(), VF, Part); |
| 4519 | |
| 4520 | for (unsigned Lane = 0; Lane < Lanes; ++Lane) { |
| 4521 | Value *Idx = Builder.CreateAdd( |
| 4522 | PartStart, ConstantInt::get(PtrInd->getType(), Lane)); |
| 4523 | Value *GlobalIdx = Builder.CreateAdd(PtrInd, Idx); |
| 4524 | Value *SclrGep = emitTransformedIndex(Builder, GlobalIdx, PSE.getSE(), |
| 4525 | DL, II, State.CFG.PrevBB); |
| 4526 | SclrGep->setName("next.gep"); |
| 4527 | State.set(PhiR, SclrGep, VPIteration(Part, Lane)); |
| 4528 | } |
| 4529 | } |
| 4530 | return; |
| 4531 | } |
| 4532 | assert(isa<SCEVConstant>(II.getStep()) &&(static_cast <bool> (isa<SCEVConstant>(II.getStep ()) && "Induction step not a SCEV constant!") ? void ( 0) : __assert_fail ("isa<SCEVConstant>(II.getStep()) && \"Induction step not a SCEV constant!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4533, __extension__ __PRETTY_FUNCTION__)) |
| 4533 | "Induction step not a SCEV constant!")(static_cast <bool> (isa<SCEVConstant>(II.getStep ()) && "Induction step not a SCEV constant!") ? void ( 0) : __assert_fail ("isa<SCEVConstant>(II.getStep()) && \"Induction step not a SCEV constant!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4533, __extension__ __PRETTY_FUNCTION__)); |
| 4534 | Type *PhiType = II.getStep()->getType(); |
| 4535 | |
| 4536 | // Build a pointer phi |
| 4537 | Value *ScalarStartValue = PhiR->getStartValue()->getLiveInIRValue(); |
| 4538 | Type *ScStValueType = ScalarStartValue->getType(); |
| 4539 | PHINode *NewPointerPhi = |
| 4540 | PHINode::Create(ScStValueType, 2, "pointer.phi", CanonicalIV); |
| 4541 | NewPointerPhi->addIncoming(ScalarStartValue, LoopVectorPreHeader); |
| 4542 | |
| 4543 | // A pointer induction, performed by using a gep |
| 4544 | BasicBlock *LoopLatch = LI->getLoopFor(LoopVectorBody)->getLoopLatch(); |
| 4545 | Instruction *InductionLoc = LoopLatch->getTerminator(); |
| 4546 | const SCEV *ScalarStep = II.getStep(); |
| 4547 | SCEVExpander Exp(*PSE.getSE(), DL, "induction"); |
| 4548 | Value *ScalarStepValue = |
| 4549 | Exp.expandCodeFor(ScalarStep, PhiType, InductionLoc); |
| 4550 | Value *RuntimeVF = getRuntimeVF(Builder, PhiType, VF); |
| 4551 | Value *NumUnrolledElems = |
| 4552 | Builder.CreateMul(RuntimeVF, ConstantInt::get(PhiType, State.UF)); |
| 4553 | Value *InductionGEP = GetElementPtrInst::Create( |
| 4554 | II.getElementType(), NewPointerPhi, |
| 4555 | Builder.CreateMul(ScalarStepValue, NumUnrolledElems), "ptr.ind", |
| 4556 | InductionLoc); |
| 4557 | NewPointerPhi->addIncoming(InductionGEP, LoopLatch); |
| 4558 | |
| 4559 | // Create UF many actual address geps that use the pointer |
| 4560 | // phi as base and a vectorized version of the step value |
| 4561 | // (<step*0, ..., step*N>) as offset. |
| 4562 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 4563 | Type *VecPhiType = VectorType::get(PhiType, State.VF); |
| 4564 | Value *StartOffsetScalar = |
| 4565 | Builder.CreateMul(RuntimeVF, ConstantInt::get(PhiType, Part)); |
| 4566 | Value *StartOffset = |
| 4567 | Builder.CreateVectorSplat(State.VF, StartOffsetScalar); |
| 4568 | // Create a vector of consecutive numbers from zero to VF. |
| 4569 | StartOffset = |
| 4570 | Builder.CreateAdd(StartOffset, Builder.CreateStepVector(VecPhiType)); |
| 4571 | |
| 4572 | Value *GEP = Builder.CreateGEP( |
| 4573 | II.getElementType(), NewPointerPhi, |
| 4574 | Builder.CreateMul( |
| 4575 | StartOffset, Builder.CreateVectorSplat(State.VF, ScalarStepValue), |
| 4576 | "vector.gep")); |
| 4577 | State.set(PhiR, GEP, Part); |
| 4578 | } |
| 4579 | } |
| 4580 | } |
| 4581 | } |
| 4582 | |
| 4583 | /// A helper function for checking whether an integer division-related |
| 4584 | /// instruction may divide by zero (in which case it must be predicated if |
| 4585 | /// executed conditionally in the scalar code). |
| 4586 | /// TODO: It may be worthwhile to generalize and check isKnownNonZero(). |
| 4587 | /// Non-zero divisors that are non compile-time constants will not be |
| 4588 | /// converted into multiplication, so we will still end up scalarizing |
| 4589 | /// the division, but can do so w/o predication. |
| 4590 | static bool mayDivideByZero(Instruction &I) { |
| 4591 | assert((I.getOpcode() == Instruction::UDiv ||(static_cast <bool> ((I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction ::URem || I.getOpcode() == Instruction::SRem) && "Unexpected instruction" ) ? void (0) : __assert_fail ("(I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction::URem || I.getOpcode() == Instruction::SRem) && \"Unexpected instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4595, __extension__ __PRETTY_FUNCTION__)) |
| 4592 | I.getOpcode() == Instruction::SDiv ||(static_cast <bool> ((I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction ::URem || I.getOpcode() == Instruction::SRem) && "Unexpected instruction" ) ? void (0) : __assert_fail ("(I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction::URem || I.getOpcode() == Instruction::SRem) && \"Unexpected instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4595, __extension__ __PRETTY_FUNCTION__)) |
| 4593 | I.getOpcode() == Instruction::URem ||(static_cast <bool> ((I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction ::URem || I.getOpcode() == Instruction::SRem) && "Unexpected instruction" ) ? void (0) : __assert_fail ("(I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction::URem || I.getOpcode() == Instruction::SRem) && \"Unexpected instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4595, __extension__ __PRETTY_FUNCTION__)) |
| 4594 | I.getOpcode() == Instruction::SRem) &&(static_cast <bool> ((I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction ::URem || I.getOpcode() == Instruction::SRem) && "Unexpected instruction" ) ? void (0) : __assert_fail ("(I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction::URem || I.getOpcode() == Instruction::SRem) && \"Unexpected instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4595, __extension__ __PRETTY_FUNCTION__)) |
| 4595 | "Unexpected instruction")(static_cast <bool> ((I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction ::URem || I.getOpcode() == Instruction::SRem) && "Unexpected instruction" ) ? void (0) : __assert_fail ("(I.getOpcode() == Instruction::UDiv || I.getOpcode() == Instruction::SDiv || I.getOpcode() == Instruction::URem || I.getOpcode() == Instruction::SRem) && \"Unexpected instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4595, __extension__ __PRETTY_FUNCTION__)); |
| 4596 | Value *Divisor = I.getOperand(1); |
| 4597 | auto *CInt = dyn_cast<ConstantInt>(Divisor); |
| 4598 | return !CInt || CInt->isZero(); |
| 4599 | } |
| 4600 | |
| 4601 | void InnerLoopVectorizer::widenCallInstruction(CallInst &I, VPValue *Def, |
| 4602 | VPUser &ArgOperands, |
| 4603 | VPTransformState &State) { |
| 4604 | assert(!isa<DbgInfoIntrinsic>(I) &&(static_cast <bool> (!isa<DbgInfoIntrinsic>(I) && "DbgInfoIntrinsic should have been dropped during VPlan construction" ) ? void (0) : __assert_fail ("!isa<DbgInfoIntrinsic>(I) && \"DbgInfoIntrinsic should have been dropped during VPlan construction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4605, __extension__ __PRETTY_FUNCTION__)) |
| 4605 | "DbgInfoIntrinsic should have been dropped during VPlan construction")(static_cast <bool> (!isa<DbgInfoIntrinsic>(I) && "DbgInfoIntrinsic should have been dropped during VPlan construction" ) ? void (0) : __assert_fail ("!isa<DbgInfoIntrinsic>(I) && \"DbgInfoIntrinsic should have been dropped during VPlan construction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4605, __extension__ __PRETTY_FUNCTION__)); |
| 4606 | setDebugLocFromInst(&I); |
| 4607 | |
| 4608 | Module *M = I.getParent()->getParent()->getParent(); |
| 4609 | auto *CI = cast<CallInst>(&I); |
| 4610 | |
| 4611 | SmallVector<Type *, 4> Tys; |
| 4612 | for (Value *ArgOperand : CI->args()) |
| 4613 | Tys.push_back(ToVectorTy(ArgOperand->getType(), VF.getKnownMinValue())); |
| 4614 | |
| 4615 | Intrinsic::ID ID = getVectorIntrinsicIDForCall(CI, TLI); |
| 4616 | |
| 4617 | // The flag shows whether we use Intrinsic or a usual Call for vectorized |
| 4618 | // version of the instruction. |
| 4619 | // Is it beneficial to perform intrinsic call compared to lib call? |
| 4620 | bool NeedToScalarize = false; |
| 4621 | InstructionCost CallCost = Cost->getVectorCallCost(CI, VF, NeedToScalarize); |
| 4622 | InstructionCost IntrinsicCost = ID ? Cost->getVectorIntrinsicCost(CI, VF) : 0; |
| 4623 | bool UseVectorIntrinsic = ID && IntrinsicCost <= CallCost; |
| 4624 | assert((UseVectorIntrinsic || !NeedToScalarize) &&(static_cast <bool> ((UseVectorIntrinsic || !NeedToScalarize ) && "Instruction should be scalarized elsewhere.") ? void (0) : __assert_fail ("(UseVectorIntrinsic || !NeedToScalarize) && \"Instruction should be scalarized elsewhere.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4625, __extension__ __PRETTY_FUNCTION__)) |
| 4625 | "Instruction should be scalarized elsewhere.")(static_cast <bool> ((UseVectorIntrinsic || !NeedToScalarize ) && "Instruction should be scalarized elsewhere.") ? void (0) : __assert_fail ("(UseVectorIntrinsic || !NeedToScalarize) && \"Instruction should be scalarized elsewhere.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4625, __extension__ __PRETTY_FUNCTION__)); |
| 4626 | assert((IntrinsicCost.isValid() || CallCost.isValid()) &&(static_cast <bool> ((IntrinsicCost.isValid() || CallCost .isValid()) && "Either the intrinsic cost or vector call cost must be valid" ) ? void (0) : __assert_fail ("(IntrinsicCost.isValid() || CallCost.isValid()) && \"Either the intrinsic cost or vector call cost must be valid\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4627, __extension__ __PRETTY_FUNCTION__)) |
| 4627 | "Either the intrinsic cost or vector call cost must be valid")(static_cast <bool> ((IntrinsicCost.isValid() || CallCost .isValid()) && "Either the intrinsic cost or vector call cost must be valid" ) ? void (0) : __assert_fail ("(IntrinsicCost.isValid() || CallCost.isValid()) && \"Either the intrinsic cost or vector call cost must be valid\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4627, __extension__ __PRETTY_FUNCTION__)); |
| 4628 | |
| 4629 | for (unsigned Part = 0; Part < UF; ++Part) { |
| 4630 | SmallVector<Type *, 2> TysForDecl = {CI->getType()}; |
| 4631 | SmallVector<Value *, 4> Args; |
| 4632 | for (auto &I : enumerate(ArgOperands.operands())) { |
| 4633 | // Some intrinsics have a scalar argument - don't replace it with a |
| 4634 | // vector. |
| 4635 | Value *Arg; |
| 4636 | if (!UseVectorIntrinsic || !hasVectorInstrinsicScalarOpd(ID, I.index())) |
| 4637 | Arg = State.get(I.value(), Part); |
| 4638 | else { |
| 4639 | Arg = State.get(I.value(), VPIteration(0, 0)); |
| 4640 | if (hasVectorInstrinsicOverloadedScalarOpd(ID, I.index())) |
| 4641 | TysForDecl.push_back(Arg->getType()); |
| 4642 | } |
| 4643 | Args.push_back(Arg); |
| 4644 | } |
| 4645 | |
| 4646 | Function *VectorF; |
| 4647 | if (UseVectorIntrinsic) { |
| 4648 | // Use vector version of the intrinsic. |
| 4649 | if (VF.isVector()) |
| 4650 | TysForDecl[0] = VectorType::get(CI->getType()->getScalarType(), VF); |
| 4651 | VectorF = Intrinsic::getDeclaration(M, ID, TysForDecl); |
| 4652 | assert(VectorF && "Can't retrieve vector intrinsic.")(static_cast <bool> (VectorF && "Can't retrieve vector intrinsic." ) ? void (0) : __assert_fail ("VectorF && \"Can't retrieve vector intrinsic.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4652, __extension__ __PRETTY_FUNCTION__)); |
| 4653 | } else { |
| 4654 | // Use vector version of the function call. |
| 4655 | const VFShape Shape = VFShape::get(*CI, VF, false /*HasGlobalPred*/); |
| 4656 | #ifndef NDEBUG |
| 4657 | assert(VFDatabase(*CI).getVectorizedFunction(Shape) != nullptr &&(static_cast <bool> (VFDatabase(*CI).getVectorizedFunction (Shape) != nullptr && "Can't create vector function." ) ? void (0) : __assert_fail ("VFDatabase(*CI).getVectorizedFunction(Shape) != nullptr && \"Can't create vector function.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4658, __extension__ __PRETTY_FUNCTION__)) |
| 4658 | "Can't create vector function.")(static_cast <bool> (VFDatabase(*CI).getVectorizedFunction (Shape) != nullptr && "Can't create vector function." ) ? void (0) : __assert_fail ("VFDatabase(*CI).getVectorizedFunction(Shape) != nullptr && \"Can't create vector function.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4658, __extension__ __PRETTY_FUNCTION__)); |
| 4659 | #endif |
| 4660 | VectorF = VFDatabase(*CI).getVectorizedFunction(Shape); |
| 4661 | } |
| 4662 | SmallVector<OperandBundleDef, 1> OpBundles; |
| 4663 | CI->getOperandBundlesAsDefs(OpBundles); |
| 4664 | CallInst *V = Builder.CreateCall(VectorF, Args, OpBundles); |
| 4665 | |
| 4666 | if (isa<FPMathOperator>(V)) |
| 4667 | V->copyFastMathFlags(CI); |
| 4668 | |
| 4669 | State.set(Def, V, Part); |
| 4670 | addMetadata(V, &I); |
| 4671 | } |
| 4672 | } |
| 4673 | |
| 4674 | void LoopVectorizationCostModel::collectLoopScalars(ElementCount VF) { |
| 4675 | // We should not collect Scalars more than once per VF. Right now, this |
| 4676 | // function is called from collectUniformsAndScalars(), which already does |
| 4677 | // this check. Collecting Scalars for VF=1 does not make any sense. |
| 4678 | assert(VF.isVector() && Scalars.find(VF) == Scalars.end() &&(static_cast <bool> (VF.isVector() && Scalars.find (VF) == Scalars.end() && "This function should not be visited twice for the same VF" ) ? void (0) : __assert_fail ("VF.isVector() && Scalars.find(VF) == Scalars.end() && \"This function should not be visited twice for the same VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4679, __extension__ __PRETTY_FUNCTION__)) |
| 4679 | "This function should not be visited twice for the same VF")(static_cast <bool> (VF.isVector() && Scalars.find (VF) == Scalars.end() && "This function should not be visited twice for the same VF" ) ? void (0) : __assert_fail ("VF.isVector() && Scalars.find(VF) == Scalars.end() && \"This function should not be visited twice for the same VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4679, __extension__ __PRETTY_FUNCTION__)); |
| 4680 | |
| 4681 | SmallSetVector<Instruction *, 8> Worklist; |
| 4682 | |
| 4683 | // These sets are used to seed the analysis with pointers used by memory |
| 4684 | // accesses that will remain scalar. |
| 4685 | SmallSetVector<Instruction *, 8> ScalarPtrs; |
| 4686 | SmallPtrSet<Instruction *, 8> PossibleNonScalarPtrs; |
| 4687 | auto *Latch = TheLoop->getLoopLatch(); |
| 4688 | |
| 4689 | // A helper that returns true if the use of Ptr by MemAccess will be scalar. |
| 4690 | // The pointer operands of loads and stores will be scalar as long as the |
| 4691 | // memory access is not a gather or scatter operation. The value operand of a |
| 4692 | // store will remain scalar if the store is scalarized. |
| 4693 | auto isScalarUse = [&](Instruction *MemAccess, Value *Ptr) { |
| 4694 | InstWidening WideningDecision = getWideningDecision(MemAccess, VF); |
| 4695 | assert(WideningDecision != CM_Unknown &&(static_cast <bool> (WideningDecision != CM_Unknown && "Widening decision should be ready at this moment") ? void ( 0) : __assert_fail ("WideningDecision != CM_Unknown && \"Widening decision should be ready at this moment\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4696, __extension__ __PRETTY_FUNCTION__)) |
| 4696 | "Widening decision should be ready at this moment")(static_cast <bool> (WideningDecision != CM_Unknown && "Widening decision should be ready at this moment") ? void ( 0) : __assert_fail ("WideningDecision != CM_Unknown && \"Widening decision should be ready at this moment\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4696, __extension__ __PRETTY_FUNCTION__)); |
| 4697 | if (auto *Store = dyn_cast<StoreInst>(MemAccess)) |
| 4698 | if (Ptr == Store->getValueOperand()) |
| 4699 | return WideningDecision == CM_Scalarize; |
| 4700 | assert(Ptr == getLoadStorePointerOperand(MemAccess) &&(static_cast <bool> (Ptr == getLoadStorePointerOperand( MemAccess) && "Ptr is neither a value or pointer operand" ) ? void (0) : __assert_fail ("Ptr == getLoadStorePointerOperand(MemAccess) && \"Ptr is neither a value or pointer operand\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4701, __extension__ __PRETTY_FUNCTION__)) |
| 4701 | "Ptr is neither a value or pointer operand")(static_cast <bool> (Ptr == getLoadStorePointerOperand( MemAccess) && "Ptr is neither a value or pointer operand" ) ? void (0) : __assert_fail ("Ptr == getLoadStorePointerOperand(MemAccess) && \"Ptr is neither a value or pointer operand\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4701, __extension__ __PRETTY_FUNCTION__)); |
| 4702 | return WideningDecision != CM_GatherScatter; |
| 4703 | }; |
| 4704 | |
| 4705 | // A helper that returns true if the given value is a bitcast or |
| 4706 | // getelementptr instruction contained in the loop. |
| 4707 | auto isLoopVaryingBitCastOrGEP = [&](Value *V) { |
| 4708 | return ((isa<BitCastInst>(V) && V->getType()->isPointerTy()) || |
| 4709 | isa<GetElementPtrInst>(V)) && |
| 4710 | !TheLoop->isLoopInvariant(V); |
| 4711 | }; |
| 4712 | |
| 4713 | // A helper that evaluates a memory access's use of a pointer. If the use will |
| 4714 | // be a scalar use and the pointer is only used by memory accesses, we place |
| 4715 | // the pointer in ScalarPtrs. Otherwise, the pointer is placed in |
| 4716 | // PossibleNonScalarPtrs. |
| 4717 | auto evaluatePtrUse = [&](Instruction *MemAccess, Value *Ptr) { |
| 4718 | // We only care about bitcast and getelementptr instructions contained in |
| 4719 | // the loop. |
| 4720 | if (!isLoopVaryingBitCastOrGEP(Ptr)) |
| 4721 | return; |
| 4722 | |
| 4723 | // If the pointer has already been identified as scalar (e.g., if it was |
| 4724 | // also identified as uniform), there's nothing to do. |
| 4725 | auto *I = cast<Instruction>(Ptr); |
| 4726 | if (Worklist.count(I)) |
| 4727 | return; |
| 4728 | |
| 4729 | // If the use of the pointer will be a scalar use, and all users of the |
| 4730 | // pointer are memory accesses, place the pointer in ScalarPtrs. Otherwise, |
| 4731 | // place the pointer in PossibleNonScalarPtrs. |
| 4732 | if (isScalarUse(MemAccess, Ptr) && llvm::all_of(I->users(), [&](User *U) { |
| 4733 | return isa<LoadInst>(U) || isa<StoreInst>(U); |
| 4734 | })) |
| 4735 | ScalarPtrs.insert(I); |
| 4736 | else |
| 4737 | PossibleNonScalarPtrs.insert(I); |
| 4738 | }; |
| 4739 | |
| 4740 | // We seed the scalars analysis with three classes of instructions: (1) |
| 4741 | // instructions marked uniform-after-vectorization and (2) bitcast, |
| 4742 | // getelementptr and (pointer) phi instructions used by memory accesses |
| 4743 | // requiring a scalar use. |
| 4744 | // |
| 4745 | // (1) Add to the worklist all instructions that have been identified as |
| 4746 | // uniform-after-vectorization. |
| 4747 | Worklist.insert(Uniforms[VF].begin(), Uniforms[VF].end()); |
| 4748 | |
| 4749 | // (2) Add to the worklist all bitcast and getelementptr instructions used by |
| 4750 | // memory accesses requiring a scalar use. The pointer operands of loads and |
| 4751 | // stores will be scalar as long as the memory accesses is not a gather or |
| 4752 | // scatter operation. The value operand of a store will remain scalar if the |
| 4753 | // store is scalarized. |
| 4754 | for (auto *BB : TheLoop->blocks()) |
| 4755 | for (auto &I : *BB) { |
| 4756 | if (auto *Load = dyn_cast<LoadInst>(&I)) { |
| 4757 | evaluatePtrUse(Load, Load->getPointerOperand()); |
| 4758 | } else if (auto *Store = dyn_cast<StoreInst>(&I)) { |
| 4759 | evaluatePtrUse(Store, Store->getPointerOperand()); |
| 4760 | evaluatePtrUse(Store, Store->getValueOperand()); |
| 4761 | } |
| 4762 | } |
| 4763 | for (auto *I : ScalarPtrs) |
| 4764 | if (!PossibleNonScalarPtrs.count(I)) { |
| 4765 | LLVM_DEBUG(dbgs() << "LV: Found scalar instruction: " << *I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found scalar instruction: " << *I << "\n"; } } while (false); |
| 4766 | Worklist.insert(I); |
| 4767 | } |
| 4768 | |
| 4769 | // Insert the forced scalars. |
| 4770 | // FIXME: Currently widenPHIInstruction() often creates a dead vector |
| 4771 | // induction variable when the PHI user is scalarized. |
| 4772 | auto ForcedScalar = ForcedScalars.find(VF); |
| 4773 | if (ForcedScalar != ForcedScalars.end()) |
| 4774 | for (auto *I : ForcedScalar->second) |
| 4775 | Worklist.insert(I); |
| 4776 | |
| 4777 | // Expand the worklist by looking through any bitcasts and getelementptr |
| 4778 | // instructions we've already identified as scalar. This is similar to the |
| 4779 | // expansion step in collectLoopUniforms(); however, here we're only |
| 4780 | // expanding to include additional bitcasts and getelementptr instructions. |
| 4781 | unsigned Idx = 0; |
| 4782 | while (Idx != Worklist.size()) { |
| 4783 | Instruction *Dst = Worklist[Idx++]; |
| 4784 | if (!isLoopVaryingBitCastOrGEP(Dst->getOperand(0))) |
| 4785 | continue; |
| 4786 | auto *Src = cast<Instruction>(Dst->getOperand(0)); |
| 4787 | if (llvm::all_of(Src->users(), [&](User *U) -> bool { |
| 4788 | auto *J = cast<Instruction>(U); |
| 4789 | return !TheLoop->contains(J) || Worklist.count(J) || |
| 4790 | ((isa<LoadInst>(J) || isa<StoreInst>(J)) && |
| 4791 | isScalarUse(J, Src)); |
| 4792 | })) { |
| 4793 | Worklist.insert(Src); |
| 4794 | LLVM_DEBUG(dbgs() << "LV: Found scalar instruction: " << *Src << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found scalar instruction: " << *Src << "\n"; } } while (false); |
| 4795 | } |
| 4796 | } |
| 4797 | |
| 4798 | // An induction variable will remain scalar if all users of the induction |
| 4799 | // variable and induction variable update remain scalar. |
| 4800 | for (auto &Induction : Legal->getInductionVars()) { |
| 4801 | auto *Ind = Induction.first; |
| 4802 | auto *IndUpdate = cast<Instruction>(Ind->getIncomingValueForBlock(Latch)); |
| 4803 | |
| 4804 | // If tail-folding is applied, the primary induction variable will be used |
| 4805 | // to feed a vector compare. |
| 4806 | if (Ind == Legal->getPrimaryInduction() && foldTailByMasking()) |
| 4807 | continue; |
| 4808 | |
| 4809 | // Returns true if \p Indvar is a pointer induction that is used directly by |
| 4810 | // load/store instruction \p I. |
| 4811 | auto IsDirectLoadStoreFromPtrIndvar = [&](Instruction *Indvar, |
| 4812 | Instruction *I) { |
| 4813 | return Induction.second.getKind() == |
| 4814 | InductionDescriptor::IK_PtrInduction && |
| 4815 | (isa<LoadInst>(I) || isa<StoreInst>(I)) && |
| 4816 | Indvar == getLoadStorePointerOperand(I) && isScalarUse(I, Indvar); |
| 4817 | }; |
| 4818 | |
| 4819 | // Determine if all users of the induction variable are scalar after |
| 4820 | // vectorization. |
| 4821 | auto ScalarInd = llvm::all_of(Ind->users(), [&](User *U) -> bool { |
| 4822 | auto *I = cast<Instruction>(U); |
| 4823 | return I == IndUpdate || !TheLoop->contains(I) || Worklist.count(I) || |
| 4824 | IsDirectLoadStoreFromPtrIndvar(Ind, I); |
| 4825 | }); |
| 4826 | if (!ScalarInd) |
| 4827 | continue; |
| 4828 | |
| 4829 | // Determine if all users of the induction variable update instruction are |
| 4830 | // scalar after vectorization. |
| 4831 | auto ScalarIndUpdate = |
| 4832 | llvm::all_of(IndUpdate->users(), [&](User *U) -> bool { |
| 4833 | auto *I = cast<Instruction>(U); |
| 4834 | return I == Ind || !TheLoop->contains(I) || Worklist.count(I) || |
| 4835 | IsDirectLoadStoreFromPtrIndvar(IndUpdate, I); |
| 4836 | }); |
| 4837 | if (!ScalarIndUpdate) |
| 4838 | continue; |
| 4839 | |
| 4840 | // The induction variable and its update instruction will remain scalar. |
| 4841 | Worklist.insert(Ind); |
| 4842 | Worklist.insert(IndUpdate); |
| 4843 | LLVM_DEBUG(dbgs() << "LV: Found scalar instruction: " << *Ind << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found scalar instruction: " << *Ind << "\n"; } } while (false); |
| 4844 | LLVM_DEBUG(dbgs() << "LV: Found scalar instruction: " << *IndUpdatedo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found scalar instruction: " << *IndUpdate << "\n"; } } while (false) |
| 4845 | << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found scalar instruction: " << *IndUpdate << "\n"; } } while (false); |
| 4846 | } |
| 4847 | |
| 4848 | Scalars[VF].insert(Worklist.begin(), Worklist.end()); |
| 4849 | } |
| 4850 | |
| 4851 | bool LoopVectorizationCostModel::isScalarWithPredication( |
| 4852 | Instruction *I, ElementCount VF) const { |
| 4853 | if (!blockNeedsPredicationForAnyReason(I->getParent())) |
| 4854 | return false; |
| 4855 | switch(I->getOpcode()) { |
| 4856 | default: |
| 4857 | break; |
| 4858 | case Instruction::Load: |
| 4859 | case Instruction::Store: { |
| 4860 | if (!Legal->isMaskRequired(I)) |
| 4861 | return false; |
| 4862 | auto *Ptr = getLoadStorePointerOperand(I); |
| 4863 | auto *Ty = getLoadStoreType(I); |
| 4864 | Type *VTy = Ty; |
| 4865 | if (VF.isVector()) |
| 4866 | VTy = VectorType::get(Ty, VF); |
| 4867 | const Align Alignment = getLoadStoreAlignment(I); |
| 4868 | return isa<LoadInst>(I) ? !(isLegalMaskedLoad(Ty, Ptr, Alignment) || |
| 4869 | TTI.isLegalMaskedGather(VTy, Alignment)) |
| 4870 | : !(isLegalMaskedStore(Ty, Ptr, Alignment) || |
| 4871 | TTI.isLegalMaskedScatter(VTy, Alignment)); |
| 4872 | } |
| 4873 | case Instruction::UDiv: |
| 4874 | case Instruction::SDiv: |
| 4875 | case Instruction::SRem: |
| 4876 | case Instruction::URem: |
| 4877 | return mayDivideByZero(*I); |
| 4878 | } |
| 4879 | return false; |
| 4880 | } |
| 4881 | |
| 4882 | bool LoopVectorizationCostModel::interleavedAccessCanBeWidened( |
| 4883 | Instruction *I, ElementCount VF) { |
| 4884 | assert(isAccessInterleaved(I) && "Expecting interleaved access.")(static_cast <bool> (isAccessInterleaved(I) && "Expecting interleaved access." ) ? void (0) : __assert_fail ("isAccessInterleaved(I) && \"Expecting interleaved access.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4884, __extension__ __PRETTY_FUNCTION__)); |
| 4885 | assert(getWideningDecision(I, VF) == CM_Unknown &&(static_cast <bool> (getWideningDecision(I, VF) == CM_Unknown && "Decision should not be set yet.") ? void (0) : __assert_fail ("getWideningDecision(I, VF) == CM_Unknown && \"Decision should not be set yet.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4886, __extension__ __PRETTY_FUNCTION__)) |
| 4886 | "Decision should not be set yet.")(static_cast <bool> (getWideningDecision(I, VF) == CM_Unknown && "Decision should not be set yet.") ? void (0) : __assert_fail ("getWideningDecision(I, VF) == CM_Unknown && \"Decision should not be set yet.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4886, __extension__ __PRETTY_FUNCTION__)); |
| 4887 | auto *Group = getInterleavedAccessGroup(I); |
| 4888 | assert(Group && "Must have a group.")(static_cast <bool> (Group && "Must have a group." ) ? void (0) : __assert_fail ("Group && \"Must have a group.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4888, __extension__ __PRETTY_FUNCTION__)); |
| 4889 | |
| 4890 | // If the instruction's allocated size doesn't equal it's type size, it |
| 4891 | // requires padding and will be scalarized. |
| 4892 | auto &DL = I->getModule()->getDataLayout(); |
| 4893 | auto *ScalarTy = getLoadStoreType(I); |
| 4894 | if (hasIrregularType(ScalarTy, DL)) |
| 4895 | return false; |
| 4896 | |
| 4897 | // Check if masking is required. |
| 4898 | // A Group may need masking for one of two reasons: it resides in a block that |
| 4899 | // needs predication, or it was decided to use masking to deal with gaps |
| 4900 | // (either a gap at the end of a load-access that may result in a speculative |
| 4901 | // load, or any gaps in a store-access). |
| 4902 | bool PredicatedAccessRequiresMasking = |
| 4903 | blockNeedsPredicationForAnyReason(I->getParent()) && |
| 4904 | Legal->isMaskRequired(I); |
| 4905 | bool LoadAccessWithGapsRequiresEpilogMasking = |
| 4906 | isa<LoadInst>(I) && Group->requiresScalarEpilogue() && |
| 4907 | !isScalarEpilogueAllowed(); |
| 4908 | bool StoreAccessWithGapsRequiresMasking = |
| 4909 | isa<StoreInst>(I) && (Group->getNumMembers() < Group->getFactor()); |
| 4910 | if (!PredicatedAccessRequiresMasking && |
| 4911 | !LoadAccessWithGapsRequiresEpilogMasking && |
| 4912 | !StoreAccessWithGapsRequiresMasking) |
| 4913 | return true; |
| 4914 | |
| 4915 | // If masked interleaving is required, we expect that the user/target had |
| 4916 | // enabled it, because otherwise it either wouldn't have been created or |
| 4917 | // it should have been invalidated by the CostModel. |
| 4918 | assert(useMaskedInterleavedAccesses(TTI) &&(static_cast <bool> (useMaskedInterleavedAccesses(TTI) && "Masked interleave-groups for predicated accesses are not enabled." ) ? void (0) : __assert_fail ("useMaskedInterleavedAccesses(TTI) && \"Masked interleave-groups for predicated accesses are not enabled.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4919, __extension__ __PRETTY_FUNCTION__)) |
| 4919 | "Masked interleave-groups for predicated accesses are not enabled.")(static_cast <bool> (useMaskedInterleavedAccesses(TTI) && "Masked interleave-groups for predicated accesses are not enabled." ) ? void (0) : __assert_fail ("useMaskedInterleavedAccesses(TTI) && \"Masked interleave-groups for predicated accesses are not enabled.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4919, __extension__ __PRETTY_FUNCTION__)); |
| 4920 | |
| 4921 | if (Group->isReverse()) |
| 4922 | return false; |
| 4923 | |
| 4924 | auto *Ty = getLoadStoreType(I); |
| 4925 | const Align Alignment = getLoadStoreAlignment(I); |
| 4926 | return isa<LoadInst>(I) ? TTI.isLegalMaskedLoad(Ty, Alignment) |
| 4927 | : TTI.isLegalMaskedStore(Ty, Alignment); |
| 4928 | } |
| 4929 | |
| 4930 | bool LoopVectorizationCostModel::memoryInstructionCanBeWidened( |
| 4931 | Instruction *I, ElementCount VF) { |
| 4932 | // Get and ensure we have a valid memory instruction. |
| 4933 | assert((isa<LoadInst, StoreInst>(I)) && "Invalid memory instruction")(static_cast <bool> ((isa<LoadInst, StoreInst>(I) ) && "Invalid memory instruction") ? void (0) : __assert_fail ("(isa<LoadInst, StoreInst>(I)) && \"Invalid memory instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4933, __extension__ __PRETTY_FUNCTION__)); |
| 4934 | |
| 4935 | auto *Ptr = getLoadStorePointerOperand(I); |
| 4936 | auto *ScalarTy = getLoadStoreType(I); |
| 4937 | |
| 4938 | // In order to be widened, the pointer should be consecutive, first of all. |
| 4939 | if (!Legal->isConsecutivePtr(ScalarTy, Ptr)) |
| 4940 | return false; |
| 4941 | |
| 4942 | // If the instruction is a store located in a predicated block, it will be |
| 4943 | // scalarized. |
| 4944 | if (isScalarWithPredication(I, VF)) |
| 4945 | return false; |
| 4946 | |
| 4947 | // If the instruction's allocated size doesn't equal it's type size, it |
| 4948 | // requires padding and will be scalarized. |
| 4949 | auto &DL = I->getModule()->getDataLayout(); |
| 4950 | if (hasIrregularType(ScalarTy, DL)) |
| 4951 | return false; |
| 4952 | |
| 4953 | return true; |
| 4954 | } |
| 4955 | |
| 4956 | void LoopVectorizationCostModel::collectLoopUniforms(ElementCount VF) { |
| 4957 | // We should not collect Uniforms more than once per VF. Right now, |
| 4958 | // this function is called from collectUniformsAndScalars(), which |
| 4959 | // already does this check. Collecting Uniforms for VF=1 does not make any |
| 4960 | // sense. |
| 4961 | |
| 4962 | assert(VF.isVector() && Uniforms.find(VF) == Uniforms.end() &&(static_cast <bool> (VF.isVector() && Uniforms. find(VF) == Uniforms.end() && "This function should not be visited twice for the same VF" ) ? void (0) : __assert_fail ("VF.isVector() && Uniforms.find(VF) == Uniforms.end() && \"This function should not be visited twice for the same VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4963, __extension__ __PRETTY_FUNCTION__)) |
| 4963 | "This function should not be visited twice for the same VF")(static_cast <bool> (VF.isVector() && Uniforms. find(VF) == Uniforms.end() && "This function should not be visited twice for the same VF" ) ? void (0) : __assert_fail ("VF.isVector() && Uniforms.find(VF) == Uniforms.end() && \"This function should not be visited twice for the same VF\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 4963, __extension__ __PRETTY_FUNCTION__)); |
| 4964 | |
| 4965 | // Visit the list of Uniforms. If we'll not find any uniform value, we'll |
| 4966 | // not analyze again. Uniforms.count(VF) will return 1. |
| 4967 | Uniforms[VF].clear(); |
| 4968 | |
| 4969 | // We now know that the loop is vectorizable! |
| 4970 | // Collect instructions inside the loop that will remain uniform after |
| 4971 | // vectorization. |
| 4972 | |
| 4973 | // Global values, params and instructions outside of current loop are out of |
| 4974 | // scope. |
| 4975 | auto isOutOfScope = [&](Value *V) -> bool { |
| 4976 | Instruction *I = dyn_cast<Instruction>(V); |
| 4977 | return (!I || !TheLoop->contains(I)); |
| 4978 | }; |
| 4979 | |
| 4980 | // Worklist containing uniform instructions demanding lane 0. |
| 4981 | SetVector<Instruction *> Worklist; |
| 4982 | BasicBlock *Latch = TheLoop->getLoopLatch(); |
| 4983 | |
| 4984 | // Add uniform instructions demanding lane 0 to the worklist. Instructions |
| 4985 | // that are scalar with predication must not be considered uniform after |
| 4986 | // vectorization, because that would create an erroneous replicating region |
| 4987 | // where only a single instance out of VF should be formed. |
| 4988 | // TODO: optimize such seldom cases if found important, see PR40816. |
| 4989 | auto addToWorklistIfAllowed = [&](Instruction *I) -> void { |
| 4990 | if (isOutOfScope(I)) { |
| 4991 | LLVM_DEBUG(dbgs() << "LV: Found not uniform due to scope: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found not uniform due to scope: " << *I << "\n"; } } while (false) |
| 4992 | << *I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found not uniform due to scope: " << *I << "\n"; } } while (false); |
| 4993 | return; |
| 4994 | } |
| 4995 | if (isScalarWithPredication(I, VF)) { |
| 4996 | LLVM_DEBUG(dbgs() << "LV: Found not uniform being ScalarWithPredication: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found not uniform being ScalarWithPredication: " << *I << "\n"; } } while (false) |
| 4997 | << *I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found not uniform being ScalarWithPredication: " << *I << "\n"; } } while (false); |
| 4998 | return; |
| 4999 | } |
| 5000 | LLVM_DEBUG(dbgs() << "LV: Found uniform instruction: " << *I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found uniform instruction: " << *I << "\n"; } } while (false); |
| 5001 | Worklist.insert(I); |
| 5002 | }; |
| 5003 | |
| 5004 | // Start with the conditional branch. If the branch condition is an |
| 5005 | // instruction contained in the loop that is only used by the branch, it is |
| 5006 | // uniform. |
| 5007 | auto *Cmp = dyn_cast<Instruction>(Latch->getTerminator()->getOperand(0)); |
| 5008 | if (Cmp && TheLoop->contains(Cmp) && Cmp->hasOneUse()) |
| 5009 | addToWorklistIfAllowed(Cmp); |
| 5010 | |
| 5011 | auto isUniformDecision = [&](Instruction *I, ElementCount VF) { |
| 5012 | InstWidening WideningDecision = getWideningDecision(I, VF); |
| 5013 | assert(WideningDecision != CM_Unknown &&(static_cast <bool> (WideningDecision != CM_Unknown && "Widening decision should be ready at this moment") ? void ( 0) : __assert_fail ("WideningDecision != CM_Unknown && \"Widening decision should be ready at this moment\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5014, __extension__ __PRETTY_FUNCTION__)) |
| 5014 | "Widening decision should be ready at this moment")(static_cast <bool> (WideningDecision != CM_Unknown && "Widening decision should be ready at this moment") ? void ( 0) : __assert_fail ("WideningDecision != CM_Unknown && \"Widening decision should be ready at this moment\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5014, __extension__ __PRETTY_FUNCTION__)); |
| 5015 | |
| 5016 | // A uniform memory op is itself uniform. We exclude uniform stores |
| 5017 | // here as they demand the last lane, not the first one. |
| 5018 | if (isa<LoadInst>(I) && Legal->isUniformMemOp(*I)) { |
| 5019 | assert(WideningDecision == CM_Scalarize)(static_cast <bool> (WideningDecision == CM_Scalarize) ? void (0) : __assert_fail ("WideningDecision == CM_Scalarize" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5019, __extension__ __PRETTY_FUNCTION__)); |
| 5020 | return true; |
| 5021 | } |
| 5022 | |
| 5023 | return (WideningDecision == CM_Widen || |
| 5024 | WideningDecision == CM_Widen_Reverse || |
| 5025 | WideningDecision == CM_Interleave); |
| 5026 | }; |
| 5027 | |
| 5028 | |
| 5029 | // Returns true if Ptr is the pointer operand of a memory access instruction |
| 5030 | // I, and I is known to not require scalarization. |
| 5031 | auto isVectorizedMemAccessUse = [&](Instruction *I, Value *Ptr) -> bool { |
| 5032 | return getLoadStorePointerOperand(I) == Ptr && isUniformDecision(I, VF); |
| 5033 | }; |
| 5034 | |
| 5035 | // Holds a list of values which are known to have at least one uniform use. |
| 5036 | // Note that there may be other uses which aren't uniform. A "uniform use" |
| 5037 | // here is something which only demands lane 0 of the unrolled iterations; |
| 5038 | // it does not imply that all lanes produce the same value (e.g. this is not |
| 5039 | // the usual meaning of uniform) |
| 5040 | SetVector<Value *> HasUniformUse; |
| 5041 | |
| 5042 | // Scan the loop for instructions which are either a) known to have only |
| 5043 | // lane 0 demanded or b) are uses which demand only lane 0 of their operand. |
| 5044 | for (auto *BB : TheLoop->blocks()) |
| 5045 | for (auto &I : *BB) { |
| 5046 | if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(&I)) { |
| 5047 | switch (II->getIntrinsicID()) { |
| 5048 | case Intrinsic::sideeffect: |
| 5049 | case Intrinsic::experimental_noalias_scope_decl: |
| 5050 | case Intrinsic::assume: |
| 5051 | case Intrinsic::lifetime_start: |
| 5052 | case Intrinsic::lifetime_end: |
| 5053 | if (TheLoop->hasLoopInvariantOperands(&I)) |
| 5054 | addToWorklistIfAllowed(&I); |
| 5055 | break; |
| 5056 | default: |
| 5057 | break; |
| 5058 | } |
| 5059 | } |
| 5060 | |
| 5061 | // ExtractValue instructions must be uniform, because the operands are |
| 5062 | // known to be loop-invariant. |
| 5063 | if (auto *EVI = dyn_cast<ExtractValueInst>(&I)) { |
| 5064 | assert(isOutOfScope(EVI->getAggregateOperand()) &&(static_cast <bool> (isOutOfScope(EVI->getAggregateOperand ()) && "Expected aggregate value to be loop invariant" ) ? void (0) : __assert_fail ("isOutOfScope(EVI->getAggregateOperand()) && \"Expected aggregate value to be loop invariant\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5065, __extension__ __PRETTY_FUNCTION__)) |
| 5065 | "Expected aggregate value to be loop invariant")(static_cast <bool> (isOutOfScope(EVI->getAggregateOperand ()) && "Expected aggregate value to be loop invariant" ) ? void (0) : __assert_fail ("isOutOfScope(EVI->getAggregateOperand()) && \"Expected aggregate value to be loop invariant\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5065, __extension__ __PRETTY_FUNCTION__)); |
| 5066 | addToWorklistIfAllowed(EVI); |
| 5067 | continue; |
| 5068 | } |
| 5069 | |
| 5070 | // If there's no pointer operand, there's nothing to do. |
| 5071 | auto *Ptr = getLoadStorePointerOperand(&I); |
| 5072 | if (!Ptr) |
| 5073 | continue; |
| 5074 | |
| 5075 | // A uniform memory op is itself uniform. We exclude uniform stores |
| 5076 | // here as they demand the last lane, not the first one. |
| 5077 | if (isa<LoadInst>(I) && Legal->isUniformMemOp(I)) |
| 5078 | addToWorklistIfAllowed(&I); |
| 5079 | |
| 5080 | if (isUniformDecision(&I, VF)) { |
| 5081 | assert(isVectorizedMemAccessUse(&I, Ptr) && "consistency check")(static_cast <bool> (isVectorizedMemAccessUse(&I, Ptr ) && "consistency check") ? void (0) : __assert_fail ( "isVectorizedMemAccessUse(&I, Ptr) && \"consistency check\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5081, __extension__ __PRETTY_FUNCTION__)); |
| 5082 | HasUniformUse.insert(Ptr); |
| 5083 | } |
| 5084 | } |
| 5085 | |
| 5086 | // Add to the worklist any operands which have *only* uniform (e.g. lane 0 |
| 5087 | // demanding) users. Since loops are assumed to be in LCSSA form, this |
| 5088 | // disallows uses outside the loop as well. |
| 5089 | for (auto *V : HasUniformUse) { |
| 5090 | if (isOutOfScope(V)) |
| 5091 | continue; |
| 5092 | auto *I = cast<Instruction>(V); |
| 5093 | auto UsersAreMemAccesses = |
| 5094 | llvm::all_of(I->users(), [&](User *U) -> bool { |
| 5095 | return isVectorizedMemAccessUse(cast<Instruction>(U), V); |
| 5096 | }); |
| 5097 | if (UsersAreMemAccesses) |
| 5098 | addToWorklistIfAllowed(I); |
| 5099 | } |
| 5100 | |
| 5101 | // Expand Worklist in topological order: whenever a new instruction |
| 5102 | // is added , its users should be already inside Worklist. It ensures |
| 5103 | // a uniform instruction will only be used by uniform instructions. |
| 5104 | unsigned idx = 0; |
| 5105 | while (idx != Worklist.size()) { |
| 5106 | Instruction *I = Worklist[idx++]; |
| 5107 | |
| 5108 | for (auto OV : I->operand_values()) { |
| 5109 | // isOutOfScope operands cannot be uniform instructions. |
| 5110 | if (isOutOfScope(OV)) |
| 5111 | continue; |
| 5112 | // First order recurrence Phi's should typically be considered |
| 5113 | // non-uniform. |
| 5114 | auto *OP = dyn_cast<PHINode>(OV); |
| 5115 | if (OP && Legal->isFirstOrderRecurrence(OP)) |
| 5116 | continue; |
| 5117 | // If all the users of the operand are uniform, then add the |
| 5118 | // operand into the uniform worklist. |
| 5119 | auto *OI = cast<Instruction>(OV); |
| 5120 | if (llvm::all_of(OI->users(), [&](User *U) -> bool { |
| 5121 | auto *J = cast<Instruction>(U); |
| 5122 | return Worklist.count(J) || isVectorizedMemAccessUse(J, OI); |
| 5123 | })) |
| 5124 | addToWorklistIfAllowed(OI); |
| 5125 | } |
| 5126 | } |
| 5127 | |
| 5128 | // For an instruction to be added into Worklist above, all its users inside |
| 5129 | // the loop should also be in Worklist. However, this condition cannot be |
| 5130 | // true for phi nodes that form a cyclic dependence. We must process phi |
| 5131 | // nodes separately. An induction variable will remain uniform if all users |
| 5132 | // of the induction variable and induction variable update remain uniform. |
| 5133 | // The code below handles both pointer and non-pointer induction variables. |
| 5134 | for (auto &Induction : Legal->getInductionVars()) { |
| 5135 | auto *Ind = Induction.first; |
| 5136 | auto *IndUpdate = cast<Instruction>(Ind->getIncomingValueForBlock(Latch)); |
| 5137 | |
| 5138 | // Determine if all users of the induction variable are uniform after |
| 5139 | // vectorization. |
| 5140 | auto UniformInd = llvm::all_of(Ind->users(), [&](User *U) -> bool { |
| 5141 | auto *I = cast<Instruction>(U); |
| 5142 | return I == IndUpdate || !TheLoop->contains(I) || Worklist.count(I) || |
| 5143 | isVectorizedMemAccessUse(I, Ind); |
| 5144 | }); |
| 5145 | if (!UniformInd) |
| 5146 | continue; |
| 5147 | |
| 5148 | // Determine if all users of the induction variable update instruction are |
| 5149 | // uniform after vectorization. |
| 5150 | auto UniformIndUpdate = |
| 5151 | llvm::all_of(IndUpdate->users(), [&](User *U) -> bool { |
| 5152 | auto *I = cast<Instruction>(U); |
| 5153 | return I == Ind || !TheLoop->contains(I) || Worklist.count(I) || |
| 5154 | isVectorizedMemAccessUse(I, IndUpdate); |
| 5155 | }); |
| 5156 | if (!UniformIndUpdate) |
| 5157 | continue; |
| 5158 | |
| 5159 | // The induction variable and its update instruction will remain uniform. |
| 5160 | addToWorklistIfAllowed(Ind); |
| 5161 | addToWorklistIfAllowed(IndUpdate); |
| 5162 | } |
| 5163 | |
| 5164 | Uniforms[VF].insert(Worklist.begin(), Worklist.end()); |
| 5165 | } |
| 5166 | |
| 5167 | bool LoopVectorizationCostModel::runtimeChecksRequired() { |
| 5168 | LLVM_DEBUG(dbgs() << "LV: Performing code size checks.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Performing code size checks.\n" ; } } while (false); |
| 5169 | |
| 5170 | if (Legal->getRuntimePointerChecking()->Need) { |
| 5171 | reportVectorizationFailure("Runtime ptr check is required with -Os/-Oz", |
| 5172 | "runtime pointer checks needed. Enable vectorization of this " |
| 5173 | "loop with '#pragma clang loop vectorize(enable)' when " |
| 5174 | "compiling with -Os/-Oz", |
| 5175 | "CantVersionLoopWithOptForSize", ORE, TheLoop); |
| 5176 | return true; |
| 5177 | } |
| 5178 | |
| 5179 | if (!PSE.getUnionPredicate().getPredicates().empty()) { |
| 5180 | reportVectorizationFailure("Runtime SCEV check is required with -Os/-Oz", |
| 5181 | "runtime SCEV checks needed. Enable vectorization of this " |
| 5182 | "loop with '#pragma clang loop vectorize(enable)' when " |
| 5183 | "compiling with -Os/-Oz", |
| 5184 | "CantVersionLoopWithOptForSize", ORE, TheLoop); |
| 5185 | return true; |
| 5186 | } |
| 5187 | |
| 5188 | // FIXME: Avoid specializing for stride==1 instead of bailing out. |
| 5189 | if (!Legal->getLAI()->getSymbolicStrides().empty()) { |
| 5190 | reportVectorizationFailure("Runtime stride check for small trip count", |
| 5191 | "runtime stride == 1 checks needed. Enable vectorization of " |
| 5192 | "this loop without such check by compiling with -Os/-Oz", |
| 5193 | "CantVersionLoopWithOptForSize", ORE, TheLoop); |
| 5194 | return true; |
| 5195 | } |
| 5196 | |
| 5197 | return false; |
| 5198 | } |
| 5199 | |
| 5200 | ElementCount |
| 5201 | LoopVectorizationCostModel::getMaxLegalScalableVF(unsigned MaxSafeElements) { |
| 5202 | if (!TTI.supportsScalableVectors() && !ForceTargetSupportsScalableVectors) |
| 5203 | return ElementCount::getScalable(0); |
| 5204 | |
| 5205 | if (Hints->isScalableVectorizationDisabled()) { |
| 5206 | reportVectorizationInfo("Scalable vectorization is explicitly disabled", |
| 5207 | "ScalableVectorizationDisabled", ORE, TheLoop); |
| 5208 | return ElementCount::getScalable(0); |
| 5209 | } |
| 5210 | |
| 5211 | LLVM_DEBUG(dbgs() << "LV: Scalable vectorization is available\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Scalable vectorization is available\n" ; } } while (false); |
| 5212 | |
| 5213 | auto MaxScalableVF = ElementCount::getScalable( |
| 5214 | std::numeric_limits<ElementCount::ScalarTy>::max()); |
| 5215 | |
| 5216 | // Test that the loop-vectorizer can legalize all operations for this MaxVF. |
| 5217 | // FIXME: While for scalable vectors this is currently sufficient, this should |
| 5218 | // be replaced by a more detailed mechanism that filters out specific VFs, |
| 5219 | // instead of invalidating vectorization for a whole set of VFs based on the |
| 5220 | // MaxVF. |
| 5221 | |
| 5222 | // Disable scalable vectorization if the loop contains unsupported reductions. |
| 5223 | if (!canVectorizeReductions(MaxScalableVF)) { |
| 5224 | reportVectorizationInfo( |
| 5225 | "Scalable vectorization not supported for the reduction " |
| 5226 | "operations found in this loop.", |
| 5227 | "ScalableVFUnfeasible", ORE, TheLoop); |
| 5228 | return ElementCount::getScalable(0); |
| 5229 | } |
| 5230 | |
| 5231 | // Disable scalable vectorization if the loop contains any instructions |
| 5232 | // with element types not supported for scalable vectors. |
| 5233 | if (any_of(ElementTypesInLoop, [&](Type *Ty) { |
| 5234 | return !Ty->isVoidTy() && |
| 5235 | !this->TTI.isElementTypeLegalForScalableVector(Ty); |
| 5236 | })) { |
| 5237 | reportVectorizationInfo("Scalable vectorization is not supported " |
| 5238 | "for all element types found in this loop.", |
| 5239 | "ScalableVFUnfeasible", ORE, TheLoop); |
| 5240 | return ElementCount::getScalable(0); |
| 5241 | } |
| 5242 | |
| 5243 | if (Legal->isSafeForAnyVectorWidth()) |
| 5244 | return MaxScalableVF; |
| 5245 | |
| 5246 | // Limit MaxScalableVF by the maximum safe dependence distance. |
| 5247 | Optional<unsigned> MaxVScale = TTI.getMaxVScale(); |
| 5248 | if (!MaxVScale && TheFunction->hasFnAttribute(Attribute::VScaleRange)) |
| 5249 | MaxVScale = |
| 5250 | TheFunction->getFnAttribute(Attribute::VScaleRange).getVScaleRangeMax(); |
| 5251 | MaxScalableVF = ElementCount::getScalable( |
| 5252 | MaxVScale ? (MaxSafeElements / MaxVScale.getValue()) : 0); |
| 5253 | if (!MaxScalableVF) |
| 5254 | reportVectorizationInfo( |
| 5255 | "Max legal vector width too small, scalable vectorization " |
| 5256 | "unfeasible.", |
| 5257 | "ScalableVFUnfeasible", ORE, TheLoop); |
| 5258 | |
| 5259 | return MaxScalableVF; |
| 5260 | } |
| 5261 | |
| 5262 | FixedScalableVFPair LoopVectorizationCostModel::computeFeasibleMaxVF( |
| 5263 | unsigned ConstTripCount, ElementCount UserVF, bool FoldTailByMasking) { |
| 5264 | MinBWs = computeMinimumValueSizes(TheLoop->getBlocks(), *DB, &TTI); |
| 5265 | unsigned SmallestType, WidestType; |
| 5266 | std::tie(SmallestType, WidestType) = getSmallestAndWidestTypes(); |
| 5267 | |
| 5268 | // Get the maximum safe dependence distance in bits computed by LAA. |
| 5269 | // It is computed by MaxVF * sizeOf(type) * 8, where type is taken from |
| 5270 | // the memory accesses that is most restrictive (involved in the smallest |
| 5271 | // dependence distance). |
| 5272 | unsigned MaxSafeElements = |
| 5273 | PowerOf2Floor(Legal->getMaxSafeVectorWidthInBits() / WidestType); |
| 5274 | |
| 5275 | auto MaxSafeFixedVF = ElementCount::getFixed(MaxSafeElements); |
| 5276 | auto MaxSafeScalableVF = getMaxLegalScalableVF(MaxSafeElements); |
| 5277 | |
| 5278 | LLVM_DEBUG(dbgs() << "LV: The max safe fixed VF is: " << MaxSafeFixedVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The max safe fixed VF is: " << MaxSafeFixedVF << ".\n"; } } while (false) |
| 5279 | << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The max safe fixed VF is: " << MaxSafeFixedVF << ".\n"; } } while (false); |
| 5280 | LLVM_DEBUG(dbgs() << "LV: The max safe scalable VF is: " << MaxSafeScalableVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The max safe scalable VF is: " << MaxSafeScalableVF << ".\n"; } } while (false) |
| 5281 | << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The max safe scalable VF is: " << MaxSafeScalableVF << ".\n"; } } while (false); |
| 5282 | |
| 5283 | // First analyze the UserVF, fall back if the UserVF should be ignored. |
| 5284 | if (UserVF) { |
| 5285 | auto MaxSafeUserVF = |
| 5286 | UserVF.isScalable() ? MaxSafeScalableVF : MaxSafeFixedVF; |
| 5287 | |
| 5288 | if (ElementCount::isKnownLE(UserVF, MaxSafeUserVF)) { |
| 5289 | // If `VF=vscale x N` is safe, then so is `VF=N` |
| 5290 | if (UserVF.isScalable()) |
| 5291 | return FixedScalableVFPair( |
| 5292 | ElementCount::getFixed(UserVF.getKnownMinValue()), UserVF); |
| 5293 | else |
| 5294 | return UserVF; |
| 5295 | } |
| 5296 | |
| 5297 | assert(ElementCount::isKnownGT(UserVF, MaxSafeUserVF))(static_cast <bool> (ElementCount::isKnownGT(UserVF, MaxSafeUserVF )) ? void (0) : __assert_fail ("ElementCount::isKnownGT(UserVF, MaxSafeUserVF)" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5297, __extension__ __PRETTY_FUNCTION__)); |
| 5298 | |
| 5299 | // Only clamp if the UserVF is not scalable. If the UserVF is scalable, it |
| 5300 | // is better to ignore the hint and let the compiler choose a suitable VF. |
| 5301 | if (!UserVF.isScalable()) { |
| 5302 | LLVM_DEBUG(dbgs() << "LV: User VF=" << UserVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: User VF=" << UserVF << " is unsafe, clamping to max safe VF=" << MaxSafeFixedVF << ".\n"; } } while (false) |
| 5303 | << " is unsafe, clamping to max safe VF="do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: User VF=" << UserVF << " is unsafe, clamping to max safe VF=" << MaxSafeFixedVF << ".\n"; } } while (false) |
| 5304 | << MaxSafeFixedVF << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: User VF=" << UserVF << " is unsafe, clamping to max safe VF=" << MaxSafeFixedVF << ".\n"; } } while (false); |
| 5305 | ORE->emit([&]() { |
| 5306 | return OptimizationRemarkAnalysis(DEBUG_TYPE"loop-vectorize", "VectorizationFactor", |
| 5307 | TheLoop->getStartLoc(), |
| 5308 | TheLoop->getHeader()) |
| 5309 | << "User-specified vectorization factor " |
| 5310 | << ore::NV("UserVectorizationFactor", UserVF) |
| 5311 | << " is unsafe, clamping to maximum safe vectorization factor " |
| 5312 | << ore::NV("VectorizationFactor", MaxSafeFixedVF); |
| 5313 | }); |
| 5314 | return MaxSafeFixedVF; |
| 5315 | } |
| 5316 | |
| 5317 | if (!TTI.supportsScalableVectors() && !ForceTargetSupportsScalableVectors) { |
| 5318 | LLVM_DEBUG(dbgs() << "LV: User VF=" << UserVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: User VF=" << UserVF << " is ignored because scalable vectors are not " "available.\n"; } } while (false) |
| 5319 | << " is ignored because scalable vectors are not "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: User VF=" << UserVF << " is ignored because scalable vectors are not " "available.\n"; } } while (false) |
| 5320 | "available.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: User VF=" << UserVF << " is ignored because scalable vectors are not " "available.\n"; } } while (false); |
| 5321 | ORE->emit([&]() { |
| 5322 | return OptimizationRemarkAnalysis(DEBUG_TYPE"loop-vectorize", "VectorizationFactor", |
| 5323 | TheLoop->getStartLoc(), |
| 5324 | TheLoop->getHeader()) |
| 5325 | << "User-specified vectorization factor " |
| 5326 | << ore::NV("UserVectorizationFactor", UserVF) |
| 5327 | << " is ignored because the target does not support scalable " |
| 5328 | "vectors. The compiler will pick a more suitable value."; |
| 5329 | }); |
| 5330 | } else { |
| 5331 | LLVM_DEBUG(dbgs() << "LV: User VF=" << UserVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: User VF=" << UserVF << " is unsafe. Ignoring scalable UserVF.\n"; } } while (false) |
| 5332 | << " is unsafe. Ignoring scalable UserVF.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: User VF=" << UserVF << " is unsafe. Ignoring scalable UserVF.\n"; } } while (false); |
| 5333 | ORE->emit([&]() { |
| 5334 | return OptimizationRemarkAnalysis(DEBUG_TYPE"loop-vectorize", "VectorizationFactor", |
| 5335 | TheLoop->getStartLoc(), |
| 5336 | TheLoop->getHeader()) |
| 5337 | << "User-specified vectorization factor " |
| 5338 | << ore::NV("UserVectorizationFactor", UserVF) |
| 5339 | << " is unsafe. Ignoring the hint to let the compiler pick a " |
| 5340 | "more suitable value."; |
| 5341 | }); |
| 5342 | } |
| 5343 | } |
| 5344 | |
| 5345 | LLVM_DEBUG(dbgs() << "LV: The Smallest and Widest types: " << SmallestTypedo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The Smallest and Widest types: " << SmallestType << " / " << WidestType << " bits.\n"; } } while (false) |
| 5346 | << " / " << WidestType << " bits.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The Smallest and Widest types: " << SmallestType << " / " << WidestType << " bits.\n"; } } while (false); |
| 5347 | |
| 5348 | FixedScalableVFPair Result(ElementCount::getFixed(1), |
| 5349 | ElementCount::getScalable(0)); |
| 5350 | if (auto MaxVF = |
| 5351 | getMaximizedVFForTarget(ConstTripCount, SmallestType, WidestType, |
| 5352 | MaxSafeFixedVF, FoldTailByMasking)) |
| 5353 | Result.FixedVF = MaxVF; |
| 5354 | |
| 5355 | if (auto MaxVF = |
| 5356 | getMaximizedVFForTarget(ConstTripCount, SmallestType, WidestType, |
| 5357 | MaxSafeScalableVF, FoldTailByMasking)) |
| 5358 | if (MaxVF.isScalable()) { |
| 5359 | Result.ScalableVF = MaxVF; |
| 5360 | LLVM_DEBUG(dbgs() << "LV: Found feasible scalable VF = " << MaxVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found feasible scalable VF = " << MaxVF << "\n"; } } while (false) |
| 5361 | << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found feasible scalable VF = " << MaxVF << "\n"; } } while (false); |
| 5362 | } |
| 5363 | |
| 5364 | return Result; |
| 5365 | } |
| 5366 | |
| 5367 | FixedScalableVFPair |
| 5368 | LoopVectorizationCostModel::computeMaxVF(ElementCount UserVF, unsigned UserIC) { |
| 5369 | if (Legal->getRuntimePointerChecking()->Need && TTI.hasBranchDivergence()) { |
| 5370 | // TODO: It may by useful to do since it's still likely to be dynamically |
| 5371 | // uniform if the target can skip. |
| 5372 | reportVectorizationFailure( |
| 5373 | "Not inserting runtime ptr check for divergent target", |
| 5374 | "runtime pointer checks needed. Not enabled for divergent target", |
| 5375 | "CantVersionLoopWithDivergentTarget", ORE, TheLoop); |
| 5376 | return FixedScalableVFPair::getNone(); |
| 5377 | } |
| 5378 | |
| 5379 | unsigned TC = PSE.getSE()->getSmallConstantTripCount(TheLoop); |
| 5380 | LLVM_DEBUG(dbgs() << "LV: Found trip count: " << TC << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found trip count: " << TC << '\n'; } } while (false); |
| 5381 | if (TC == 1) { |
| 5382 | reportVectorizationFailure("Single iteration (non) loop", |
| 5383 | "loop trip count is one, irrelevant for vectorization", |
| 5384 | "SingleIterationLoop", ORE, TheLoop); |
| 5385 | return FixedScalableVFPair::getNone(); |
| 5386 | } |
| 5387 | |
| 5388 | switch (ScalarEpilogueStatus) { |
| 5389 | case CM_ScalarEpilogueAllowed: |
| 5390 | return computeFeasibleMaxVF(TC, UserVF, false); |
| 5391 | case CM_ScalarEpilogueNotAllowedUsePredicate: |
| 5392 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
| 5393 | case CM_ScalarEpilogueNotNeededUsePredicate: |
| 5394 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: vector predicate hint/switch found.\n" << "LV: Not allowing scalar epilogue, creating predicated " << "vector loop.\n"; } } while (false) |
| 5395 | dbgs() << "LV: vector predicate hint/switch found.\n"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: vector predicate hint/switch found.\n" << "LV: Not allowing scalar epilogue, creating predicated " << "vector loop.\n"; } } while (false) |
| 5396 | << "LV: Not allowing scalar epilogue, creating predicated "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: vector predicate hint/switch found.\n" << "LV: Not allowing scalar epilogue, creating predicated " << "vector loop.\n"; } } while (false) |
| 5397 | << "vector loop.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: vector predicate hint/switch found.\n" << "LV: Not allowing scalar epilogue, creating predicated " << "vector loop.\n"; } } while (false); |
| 5398 | break; |
| 5399 | case CM_ScalarEpilogueNotAllowedLowTripLoop: |
| 5400 | // fallthrough as a special case of OptForSize |
| 5401 | case CM_ScalarEpilogueNotAllowedOptSize: |
| 5402 | if (ScalarEpilogueStatus == CM_ScalarEpilogueNotAllowedOptSize) |
| 5403 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not allowing scalar epilogue due to -Os/-Oz.\n" ; } } while (false) |
| 5404 | dbgs() << "LV: Not allowing scalar epilogue due to -Os/-Oz.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not allowing scalar epilogue due to -Os/-Oz.\n" ; } } while (false); |
| 5405 | else |
| 5406 | LLVM_DEBUG(dbgs() << "LV: Not allowing scalar epilogue due to low trip "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not allowing scalar epilogue due to low trip " << "count.\n"; } } while (false) |
| 5407 | << "count.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not allowing scalar epilogue due to low trip " << "count.\n"; } } while (false); |
| 5408 | |
| 5409 | // Bail if runtime checks are required, which are not good when optimising |
| 5410 | // for size. |
| 5411 | if (runtimeChecksRequired()) |
| 5412 | return FixedScalableVFPair::getNone(); |
| 5413 | |
| 5414 | break; |
| 5415 | } |
| 5416 | |
| 5417 | // The only loops we can vectorize without a scalar epilogue, are loops with |
| 5418 | // a bottom-test and a single exiting block. We'd have to handle the fact |
| 5419 | // that not every instruction executes on the last iteration. This will |
| 5420 | // require a lane mask which varies through the vector loop body. (TODO) |
| 5421 | if (TheLoop->getExitingBlock() != TheLoop->getLoopLatch()) { |
| 5422 | // If there was a tail-folding hint/switch, but we can't fold the tail by |
| 5423 | // masking, fallback to a vectorization with a scalar epilogue. |
| 5424 | if (ScalarEpilogueStatus == CM_ScalarEpilogueNotNeededUsePredicate) { |
| 5425 | LLVM_DEBUG(dbgs() << "LV: Cannot fold tail by masking: vectorize with a "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Cannot fold tail by masking: vectorize with a " "scalar epilogue instead.\n"; } } while (false) |
| 5426 | "scalar epilogue instead.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Cannot fold tail by masking: vectorize with a " "scalar epilogue instead.\n"; } } while (false); |
| 5427 | ScalarEpilogueStatus = CM_ScalarEpilogueAllowed; |
| 5428 | return computeFeasibleMaxVF(TC, UserVF, false); |
| 5429 | } |
| 5430 | return FixedScalableVFPair::getNone(); |
| 5431 | } |
| 5432 | |
| 5433 | // Now try the tail folding |
| 5434 | |
| 5435 | // Invalidate interleave groups that require an epilogue if we can't mask |
| 5436 | // the interleave-group. |
| 5437 | if (!useMaskedInterleavedAccesses(TTI)) { |
| 5438 | assert(WideningDecisions.empty() && Uniforms.empty() && Scalars.empty() &&(static_cast <bool> (WideningDecisions.empty() && Uniforms.empty() && Scalars.empty() && "No decisions should have been taken at this point" ) ? void (0) : __assert_fail ("WideningDecisions.empty() && Uniforms.empty() && Scalars.empty() && \"No decisions should have been taken at this point\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5439, __extension__ __PRETTY_FUNCTION__)) |
| 5439 | "No decisions should have been taken at this point")(static_cast <bool> (WideningDecisions.empty() && Uniforms.empty() && Scalars.empty() && "No decisions should have been taken at this point" ) ? void (0) : __assert_fail ("WideningDecisions.empty() && Uniforms.empty() && Scalars.empty() && \"No decisions should have been taken at this point\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5439, __extension__ __PRETTY_FUNCTION__)); |
| 5440 | // Note: There is no need to invalidate any cost modeling decisions here, as |
| 5441 | // non where taken so far. |
| 5442 | InterleaveInfo.invalidateGroupsRequiringScalarEpilogue(); |
| 5443 | } |
| 5444 | |
| 5445 | FixedScalableVFPair MaxFactors = computeFeasibleMaxVF(TC, UserVF, true); |
| 5446 | // Avoid tail folding if the trip count is known to be a multiple of any VF |
| 5447 | // we chose. |
| 5448 | // FIXME: The condition below pessimises the case for fixed-width vectors, |
| 5449 | // when scalable VFs are also candidates for vectorization. |
| 5450 | if (MaxFactors.FixedVF.isVector() && !MaxFactors.ScalableVF) { |
| 5451 | ElementCount MaxFixedVF = MaxFactors.FixedVF; |
| 5452 | assert((UserVF.isNonZero() || isPowerOf2_32(MaxFixedVF.getFixedValue())) &&(static_cast <bool> ((UserVF.isNonZero() || isPowerOf2_32 (MaxFixedVF.getFixedValue())) && "MaxFixedVF must be a power of 2" ) ? void (0) : __assert_fail ("(UserVF.isNonZero() || isPowerOf2_32(MaxFixedVF.getFixedValue())) && \"MaxFixedVF must be a power of 2\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5453, __extension__ __PRETTY_FUNCTION__)) |
| 5453 | "MaxFixedVF must be a power of 2")(static_cast <bool> ((UserVF.isNonZero() || isPowerOf2_32 (MaxFixedVF.getFixedValue())) && "MaxFixedVF must be a power of 2" ) ? void (0) : __assert_fail ("(UserVF.isNonZero() || isPowerOf2_32(MaxFixedVF.getFixedValue())) && \"MaxFixedVF must be a power of 2\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5453, __extension__ __PRETTY_FUNCTION__)); |
| 5454 | unsigned MaxVFtimesIC = UserIC ? MaxFixedVF.getFixedValue() * UserIC |
| 5455 | : MaxFixedVF.getFixedValue(); |
| 5456 | ScalarEvolution *SE = PSE.getSE(); |
| 5457 | const SCEV *BackedgeTakenCount = PSE.getBackedgeTakenCount(); |
| 5458 | const SCEV *ExitCount = SE->getAddExpr( |
| 5459 | BackedgeTakenCount, SE->getOne(BackedgeTakenCount->getType())); |
| 5460 | const SCEV *Rem = SE->getURemExpr( |
| 5461 | SE->applyLoopGuards(ExitCount, TheLoop), |
| 5462 | SE->getConstant(BackedgeTakenCount->getType(), MaxVFtimesIC)); |
| 5463 | if (Rem->isZero()) { |
| 5464 | // Accept MaxFixedVF if we do not have a tail. |
| 5465 | LLVM_DEBUG(dbgs() << "LV: No tail will remain for any chosen VF.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: No tail will remain for any chosen VF.\n" ; } } while (false); |
| 5466 | return MaxFactors; |
| 5467 | } |
| 5468 | } |
| 5469 | |
| 5470 | // For scalable vectors don't use tail folding for low trip counts or |
| 5471 | // optimizing for code size. We only permit this if the user has explicitly |
| 5472 | // requested it. |
| 5473 | if (ScalarEpilogueStatus != CM_ScalarEpilogueNotNeededUsePredicate && |
| 5474 | ScalarEpilogueStatus != CM_ScalarEpilogueNotAllowedUsePredicate && |
| 5475 | MaxFactors.ScalableVF.isVector()) |
| 5476 | MaxFactors.ScalableVF = ElementCount::getScalable(0); |
| 5477 | |
| 5478 | // If we don't know the precise trip count, or if the trip count that we |
| 5479 | // found modulo the vectorization factor is not zero, try to fold the tail |
| 5480 | // by masking. |
| 5481 | // FIXME: look for a smaller MaxVF that does divide TC rather than masking. |
| 5482 | if (Legal->prepareToFoldTailByMasking()) { |
| 5483 | FoldTailByMasking = true; |
| 5484 | return MaxFactors; |
| 5485 | } |
| 5486 | |
| 5487 | // If there was a tail-folding hint/switch, but we can't fold the tail by |
| 5488 | // masking, fallback to a vectorization with a scalar epilogue. |
| 5489 | if (ScalarEpilogueStatus == CM_ScalarEpilogueNotNeededUsePredicate) { |
| 5490 | LLVM_DEBUG(dbgs() << "LV: Cannot fold tail by masking: vectorize with a "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Cannot fold tail by masking: vectorize with a " "scalar epilogue instead.\n"; } } while (false) |
| 5491 | "scalar epilogue instead.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Cannot fold tail by masking: vectorize with a " "scalar epilogue instead.\n"; } } while (false); |
| 5492 | ScalarEpilogueStatus = CM_ScalarEpilogueAllowed; |
| 5493 | return MaxFactors; |
| 5494 | } |
| 5495 | |
| 5496 | if (ScalarEpilogueStatus == CM_ScalarEpilogueNotAllowedUsePredicate) { |
| 5497 | LLVM_DEBUG(dbgs() << "LV: Can't fold tail by masking: don't vectorize\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Can't fold tail by masking: don't vectorize\n" ; } } while (false); |
| 5498 | return FixedScalableVFPair::getNone(); |
| 5499 | } |
| 5500 | |
| 5501 | if (TC == 0) { |
| 5502 | reportVectorizationFailure( |
| 5503 | "Unable to calculate the loop count due to complex control flow", |
| 5504 | "unable to calculate the loop count due to complex control flow", |
| 5505 | "UnknownLoopCountComplexCFG", ORE, TheLoop); |
| 5506 | return FixedScalableVFPair::getNone(); |
| 5507 | } |
| 5508 | |
| 5509 | reportVectorizationFailure( |
| 5510 | "Cannot optimize for size and vectorize at the same time.", |
| 5511 | "cannot optimize for size and vectorize at the same time. " |
| 5512 | "Enable vectorization of this loop with '#pragma clang loop " |
| 5513 | "vectorize(enable)' when compiling with -Os/-Oz", |
| 5514 | "NoTailLoopWithOptForSize", ORE, TheLoop); |
| 5515 | return FixedScalableVFPair::getNone(); |
| 5516 | } |
| 5517 | |
| 5518 | ElementCount LoopVectorizationCostModel::getMaximizedVFForTarget( |
| 5519 | unsigned ConstTripCount, unsigned SmallestType, unsigned WidestType, |
| 5520 | const ElementCount &MaxSafeVF, bool FoldTailByMasking) { |
| 5521 | bool ComputeScalableMaxVF = MaxSafeVF.isScalable(); |
| 5522 | TypeSize WidestRegister = TTI.getRegisterBitWidth( |
| 5523 | ComputeScalableMaxVF ? TargetTransformInfo::RGK_ScalableVector |
| 5524 | : TargetTransformInfo::RGK_FixedWidthVector); |
| 5525 | |
| 5526 | // Convenience function to return the minimum of two ElementCounts. |
| 5527 | auto MinVF = [](const ElementCount &LHS, const ElementCount &RHS) { |
| 5528 | assert((LHS.isScalable() == RHS.isScalable()) &&(static_cast <bool> ((LHS.isScalable() == RHS.isScalable ()) && "Scalable flags must match") ? void (0) : __assert_fail ("(LHS.isScalable() == RHS.isScalable()) && \"Scalable flags must match\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5529, __extension__ __PRETTY_FUNCTION__)) |
| 5529 | "Scalable flags must match")(static_cast <bool> ((LHS.isScalable() == RHS.isScalable ()) && "Scalable flags must match") ? void (0) : __assert_fail ("(LHS.isScalable() == RHS.isScalable()) && \"Scalable flags must match\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5529, __extension__ __PRETTY_FUNCTION__)); |
| 5530 | return ElementCount::isKnownLT(LHS, RHS) ? LHS : RHS; |
| 5531 | }; |
| 5532 | |
| 5533 | // Ensure MaxVF is a power of 2; the dependence distance bound may not be. |
| 5534 | // Note that both WidestRegister and WidestType may not be a powers of 2. |
| 5535 | auto MaxVectorElementCount = ElementCount::get( |
| 5536 | PowerOf2Floor(WidestRegister.getKnownMinSize() / WidestType), |
| 5537 | ComputeScalableMaxVF); |
| 5538 | MaxVectorElementCount = MinVF(MaxVectorElementCount, MaxSafeVF); |
| 5539 | LLVM_DEBUG(dbgs() << "LV: The Widest register safe to use is: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The Widest register safe to use is: " << (MaxVectorElementCount * WidestType) << " bits.\n" ; } } while (false) |
| 5540 | << (MaxVectorElementCount * WidestType) << " bits.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The Widest register safe to use is: " << (MaxVectorElementCount * WidestType) << " bits.\n" ; } } while (false); |
| 5541 | |
| 5542 | if (!MaxVectorElementCount) { |
| 5543 | LLVM_DEBUG(dbgs() << "LV: The target has no "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The target has no " << (ComputeScalableMaxVF ? "scalable" : "fixed") << " vector registers.\n"; } } while (false) |
| 5544 | << (ComputeScalableMaxVF ? "scalable" : "fixed")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The target has no " << (ComputeScalableMaxVF ? "scalable" : "fixed") << " vector registers.\n"; } } while (false) |
| 5545 | << " vector registers.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The target has no " << (ComputeScalableMaxVF ? "scalable" : "fixed") << " vector registers.\n"; } } while (false); |
| 5546 | return ElementCount::getFixed(1); |
| 5547 | } |
| 5548 | |
| 5549 | const auto TripCountEC = ElementCount::getFixed(ConstTripCount); |
| 5550 | if (ConstTripCount && |
| 5551 | ElementCount::isKnownLE(TripCountEC, MaxVectorElementCount) && |
| 5552 | (!FoldTailByMasking || isPowerOf2_32(ConstTripCount))) { |
| 5553 | // If loop trip count (TC) is known at compile time there is no point in |
| 5554 | // choosing VF greater than TC (as done in the loop below). Select maximum |
| 5555 | // power of two which doesn't exceed TC. |
| 5556 | // If MaxVectorElementCount is scalable, we only fall back on a fixed VF |
| 5557 | // when the TC is less than or equal to the known number of lanes. |
| 5558 | auto ClampedConstTripCount = PowerOf2Floor(ConstTripCount); |
| 5559 | LLVM_DEBUG(dbgs() << "LV: Clamping the MaxVF to maximum power of two not "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Clamping the MaxVF to maximum power of two not " "exceeding the constant trip count: " << ClampedConstTripCount << "\n"; } } while (false) |
| 5560 | "exceeding the constant trip count: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Clamping the MaxVF to maximum power of two not " "exceeding the constant trip count: " << ClampedConstTripCount << "\n"; } } while (false) |
| 5561 | << ClampedConstTripCount << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Clamping the MaxVF to maximum power of two not " "exceeding the constant trip count: " << ClampedConstTripCount << "\n"; } } while (false); |
| 5562 | return ElementCount::getFixed(ClampedConstTripCount); |
| 5563 | } |
| 5564 | |
| 5565 | ElementCount MaxVF = MaxVectorElementCount; |
| 5566 | if (TTI.shouldMaximizeVectorBandwidth() || |
| 5567 | (MaximizeBandwidth && isScalarEpilogueAllowed())) { |
| 5568 | auto MaxVectorElementCountMaxBW = ElementCount::get( |
| 5569 | PowerOf2Floor(WidestRegister.getKnownMinSize() / SmallestType), |
| 5570 | ComputeScalableMaxVF); |
| 5571 | MaxVectorElementCountMaxBW = MinVF(MaxVectorElementCountMaxBW, MaxSafeVF); |
| 5572 | |
| 5573 | // Collect all viable vectorization factors larger than the default MaxVF |
| 5574 | // (i.e. MaxVectorElementCount). |
| 5575 | SmallVector<ElementCount, 8> VFs; |
| 5576 | for (ElementCount VS = MaxVectorElementCount * 2; |
| 5577 | ElementCount::isKnownLE(VS, MaxVectorElementCountMaxBW); VS *= 2) |
| 5578 | VFs.push_back(VS); |
| 5579 | |
| 5580 | // For each VF calculate its register usage. |
| 5581 | auto RUs = calculateRegisterUsage(VFs); |
| 5582 | |
| 5583 | // Select the largest VF which doesn't require more registers than existing |
| 5584 | // ones. |
| 5585 | for (int i = RUs.size() - 1; i >= 0; --i) { |
| 5586 | bool Selected = true; |
| 5587 | for (auto &pair : RUs[i].MaxLocalUsers) { |
| 5588 | unsigned TargetNumRegisters = TTI.getNumberOfRegisters(pair.first); |
| 5589 | if (pair.second > TargetNumRegisters) |
| 5590 | Selected = false; |
| 5591 | } |
| 5592 | if (Selected) { |
| 5593 | MaxVF = VFs[i]; |
| 5594 | break; |
| 5595 | } |
| 5596 | } |
| 5597 | if (ElementCount MinVF = |
| 5598 | TTI.getMinimumVF(SmallestType, ComputeScalableMaxVF)) { |
| 5599 | if (ElementCount::isKnownLT(MaxVF, MinVF)) { |
| 5600 | LLVM_DEBUG(dbgs() << "LV: Overriding calculated MaxVF(" << MaxVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Overriding calculated MaxVF(" << MaxVF << ") with target's minimum: " << MinVF << '\n'; } } while (false) |
| 5601 | << ") with target's minimum: " << MinVF << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Overriding calculated MaxVF(" << MaxVF << ") with target's minimum: " << MinVF << '\n'; } } while (false); |
| 5602 | MaxVF = MinVF; |
| 5603 | } |
| 5604 | } |
| 5605 | } |
| 5606 | return MaxVF; |
| 5607 | } |
| 5608 | |
| 5609 | Optional<unsigned> LoopVectorizationCostModel::getVScaleForTuning() const { |
| 5610 | if (TheFunction->hasFnAttribute(Attribute::VScaleRange)) { |
| 5611 | auto Attr = TheFunction->getFnAttribute(Attribute::VScaleRange); |
| 5612 | auto Min = Attr.getVScaleRangeMin(); |
| 5613 | auto Max = Attr.getVScaleRangeMax(); |
| 5614 | if (Max && Min == Max) |
| 5615 | return Max; |
| 5616 | } |
| 5617 | |
| 5618 | return TTI.getVScaleForTuning(); |
| 5619 | } |
| 5620 | |
| 5621 | bool LoopVectorizationCostModel::isMoreProfitable( |
| 5622 | const VectorizationFactor &A, const VectorizationFactor &B) const { |
| 5623 | InstructionCost CostA = A.Cost; |
| 5624 | InstructionCost CostB = B.Cost; |
| 5625 | |
| 5626 | unsigned MaxTripCount = PSE.getSE()->getSmallConstantMaxTripCount(TheLoop); |
| 5627 | |
| 5628 | if (!A.Width.isScalable() && !B.Width.isScalable() && FoldTailByMasking && |
| 5629 | MaxTripCount) { |
| 5630 | // If we are folding the tail and the trip count is a known (possibly small) |
| 5631 | // constant, the trip count will be rounded up to an integer number of |
| 5632 | // iterations. The total cost will be PerIterationCost*ceil(TripCount/VF), |
| 5633 | // which we compare directly. When not folding the tail, the total cost will |
| 5634 | // be PerIterationCost*floor(TC/VF) + Scalar remainder cost, and so is |
| 5635 | // approximated with the per-lane cost below instead of using the tripcount |
| 5636 | // as here. |
| 5637 | auto RTCostA = CostA * divideCeil(MaxTripCount, A.Width.getFixedValue()); |
| 5638 | auto RTCostB = CostB * divideCeil(MaxTripCount, B.Width.getFixedValue()); |
| 5639 | return RTCostA < RTCostB; |
| 5640 | } |
| 5641 | |
| 5642 | // Improve estimate for the vector width if it is scalable. |
| 5643 | unsigned EstimatedWidthA = A.Width.getKnownMinValue(); |
| 5644 | unsigned EstimatedWidthB = B.Width.getKnownMinValue(); |
| 5645 | if (Optional<unsigned> VScale = getVScaleForTuning()) { |
| 5646 | if (A.Width.isScalable()) |
| 5647 | EstimatedWidthA *= VScale.getValue(); |
| 5648 | if (B.Width.isScalable()) |
| 5649 | EstimatedWidthB *= VScale.getValue(); |
| 5650 | } |
| 5651 | |
| 5652 | // Assume vscale may be larger than 1 (or the value being tuned for), |
| 5653 | // so that scalable vectorization is slightly favorable over fixed-width |
| 5654 | // vectorization. |
| 5655 | if (A.Width.isScalable() && !B.Width.isScalable()) |
| 5656 | return (CostA * B.Width.getFixedValue()) <= (CostB * EstimatedWidthA); |
| 5657 | |
| 5658 | // To avoid the need for FP division: |
| 5659 | // (CostA / A.Width) < (CostB / B.Width) |
| 5660 | // <=> (CostA * B.Width) < (CostB * A.Width) |
| 5661 | return (CostA * EstimatedWidthB) < (CostB * EstimatedWidthA); |
| 5662 | } |
| 5663 | |
| 5664 | VectorizationFactor LoopVectorizationCostModel::selectVectorizationFactor( |
| 5665 | const ElementCountSet &VFCandidates) { |
| 5666 | InstructionCost ExpectedCost = expectedCost(ElementCount::getFixed(1)).first; |
| 5667 | LLVM_DEBUG(dbgs() << "LV: Scalar loop costs: " << ExpectedCost << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Scalar loop costs: " << ExpectedCost << ".\n"; } } while (false); |
| 5668 | assert(ExpectedCost.isValid() && "Unexpected invalid cost for scalar loop")(static_cast <bool> (ExpectedCost.isValid() && "Unexpected invalid cost for scalar loop" ) ? void (0) : __assert_fail ("ExpectedCost.isValid() && \"Unexpected invalid cost for scalar loop\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5668, __extension__ __PRETTY_FUNCTION__)); |
| 5669 | assert(VFCandidates.count(ElementCount::getFixed(1)) &&(static_cast <bool> (VFCandidates.count(ElementCount::getFixed (1)) && "Expected Scalar VF to be a candidate") ? void (0) : __assert_fail ("VFCandidates.count(ElementCount::getFixed(1)) && \"Expected Scalar VF to be a candidate\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5670, __extension__ __PRETTY_FUNCTION__)) |
| 5670 | "Expected Scalar VF to be a candidate")(static_cast <bool> (VFCandidates.count(ElementCount::getFixed (1)) && "Expected Scalar VF to be a candidate") ? void (0) : __assert_fail ("VFCandidates.count(ElementCount::getFixed(1)) && \"Expected Scalar VF to be a candidate\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5670, __extension__ __PRETTY_FUNCTION__)); |
| 5671 | |
| 5672 | const VectorizationFactor ScalarCost(ElementCount::getFixed(1), ExpectedCost); |
| 5673 | VectorizationFactor ChosenFactor = ScalarCost; |
| 5674 | |
| 5675 | bool ForceVectorization = Hints->getForce() == LoopVectorizeHints::FK_Enabled; |
| 5676 | if (ForceVectorization && VFCandidates.size() > 1) { |
| 5677 | // Ignore scalar width, because the user explicitly wants vectorization. |
| 5678 | // Initialize cost to max so that VF = 2 is, at least, chosen during cost |
| 5679 | // evaluation. |
| 5680 | ChosenFactor.Cost = InstructionCost::getMax(); |
| 5681 | } |
| 5682 | |
| 5683 | SmallVector<InstructionVFPair> InvalidCosts; |
| 5684 | for (const auto &i : VFCandidates) { |
| 5685 | // The cost for scalar VF=1 is already calculated, so ignore it. |
| 5686 | if (i.isScalar()) |
| 5687 | continue; |
| 5688 | |
| 5689 | VectorizationCostTy C = expectedCost(i, &InvalidCosts); |
| 5690 | VectorizationFactor Candidate(i, C.first); |
| 5691 | |
| 5692 | #ifndef NDEBUG |
| 5693 | unsigned AssumedMinimumVscale = 1; |
| 5694 | if (Optional<unsigned> VScale = getVScaleForTuning()) |
| 5695 | AssumedMinimumVscale = VScale.getValue(); |
| 5696 | unsigned Width = |
| 5697 | Candidate.Width.isScalable() |
| 5698 | ? Candidate.Width.getKnownMinValue() * AssumedMinimumVscale |
| 5699 | : Candidate.Width.getFixedValue(); |
| 5700 | LLVM_DEBUG(dbgs() << "LV: Vector loop of width " << ido { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Vector loop of width " << i << " costs: " << (Candidate.Cost / Width ); } } while (false) |
| 5701 | << " costs: " << (Candidate.Cost / Width))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Vector loop of width " << i << " costs: " << (Candidate.Cost / Width ); } } while (false); |
| 5702 | if (i.isScalable()) |
| 5703 | LLVM_DEBUG(dbgs() << " (assuming a minimum vscale of "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << " (assuming a minimum vscale of " << AssumedMinimumVscale << ")"; } } while (false ) |
| 5704 | << AssumedMinimumVscale << ")")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << " (assuming a minimum vscale of " << AssumedMinimumVscale << ")"; } } while (false ); |
| 5705 | LLVM_DEBUG(dbgs() << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << ".\n"; } } while (false ); |
| 5706 | #endif |
| 5707 | |
| 5708 | if (!C.second && !ForceVectorization) { |
| 5709 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not considering vector loop of width " << i << " because it will not generate any vector instructions.\n" ; } } while (false) |
| 5710 | dbgs() << "LV: Not considering vector loop of width " << ido { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not considering vector loop of width " << i << " because it will not generate any vector instructions.\n" ; } } while (false) |
| 5711 | << " because it will not generate any vector instructions.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not considering vector loop of width " << i << " because it will not generate any vector instructions.\n" ; } } while (false); |
| 5712 | continue; |
| 5713 | } |
| 5714 | |
| 5715 | // If profitable add it to ProfitableVF list. |
| 5716 | if (isMoreProfitable(Candidate, ScalarCost)) |
| 5717 | ProfitableVFs.push_back(Candidate); |
| 5718 | |
| 5719 | if (isMoreProfitable(Candidate, ChosenFactor)) |
| 5720 | ChosenFactor = Candidate; |
| 5721 | } |
| 5722 | |
| 5723 | // Emit a report of VFs with invalid costs in the loop. |
| 5724 | if (!InvalidCosts.empty()) { |
| 5725 | // Group the remarks per instruction, keeping the instruction order from |
| 5726 | // InvalidCosts. |
| 5727 | std::map<Instruction *, unsigned> Numbering; |
| 5728 | unsigned I = 0; |
| 5729 | for (auto &Pair : InvalidCosts) |
| 5730 | if (!Numbering.count(Pair.first)) |
| 5731 | Numbering[Pair.first] = I++; |
| 5732 | |
| 5733 | // Sort the list, first on instruction(number) then on VF. |
| 5734 | llvm::sort(InvalidCosts, |
| 5735 | [&Numbering](InstructionVFPair &A, InstructionVFPair &B) { |
| 5736 | if (Numbering[A.first] != Numbering[B.first]) |
| 5737 | return Numbering[A.first] < Numbering[B.first]; |
| 5738 | ElementCountComparator ECC; |
| 5739 | return ECC(A.second, B.second); |
| 5740 | }); |
| 5741 | |
| 5742 | // For a list of ordered instruction-vf pairs: |
| 5743 | // [(load, vf1), (load, vf2), (store, vf1)] |
| 5744 | // Group the instructions together to emit separate remarks for: |
| 5745 | // load (vf1, vf2) |
| 5746 | // store (vf1) |
| 5747 | auto Tail = ArrayRef<InstructionVFPair>(InvalidCosts); |
| 5748 | auto Subset = ArrayRef<InstructionVFPair>(); |
| 5749 | do { |
| 5750 | if (Subset.empty()) |
| 5751 | Subset = Tail.take_front(1); |
| 5752 | |
| 5753 | Instruction *I = Subset.front().first; |
| 5754 | |
| 5755 | // If the next instruction is different, or if there are no other pairs, |
| 5756 | // emit a remark for the collated subset. e.g. |
| 5757 | // [(load, vf1), (load, vf2))] |
| 5758 | // to emit: |
| 5759 | // remark: invalid costs for 'load' at VF=(vf, vf2) |
| 5760 | if (Subset == Tail || Tail[Subset.size()].first != I) { |
| 5761 | std::string OutString; |
| 5762 | raw_string_ostream OS(OutString); |
| 5763 | assert(!Subset.empty() && "Unexpected empty range")(static_cast <bool> (!Subset.empty() && "Unexpected empty range" ) ? void (0) : __assert_fail ("!Subset.empty() && \"Unexpected empty range\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5763, __extension__ __PRETTY_FUNCTION__)); |
| 5764 | OS << "Instruction with invalid costs prevented vectorization at VF=("; |
| 5765 | for (auto &Pair : Subset) |
| 5766 | OS << (Pair.second == Subset.front().second ? "" : ", ") |
| 5767 | << Pair.second; |
| 5768 | OS << "):"; |
| 5769 | if (auto *CI = dyn_cast<CallInst>(I)) |
| 5770 | OS << " call to " << CI->getCalledFunction()->getName(); |
| 5771 | else |
| 5772 | OS << " " << I->getOpcodeName(); |
| 5773 | OS.flush(); |
| 5774 | reportVectorizationInfo(OutString, "InvalidCost", ORE, TheLoop, I); |
| 5775 | Tail = Tail.drop_front(Subset.size()); |
| 5776 | Subset = {}; |
| 5777 | } else |
| 5778 | // Grow the subset by one element |
| 5779 | Subset = Tail.take_front(Subset.size() + 1); |
| 5780 | } while (!Tail.empty()); |
| 5781 | } |
| 5782 | |
| 5783 | if (!EnableCondStoresVectorization && NumPredStores) { |
| 5784 | reportVectorizationFailure("There are conditional stores.", |
| 5785 | "store that is conditionally executed prevents vectorization", |
| 5786 | "ConditionalStore", ORE, TheLoop); |
| 5787 | ChosenFactor = ScalarCost; |
| 5788 | } |
| 5789 | |
| 5790 | LLVM_DEBUG(if (ForceVectorization && !ChosenFactor.Width.isScalar() &&do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { if (ForceVectorization && !ChosenFactor .Width.isScalar() && ChosenFactor.Cost >= ScalarCost .Cost) dbgs() << "LV: Vectorization seems to be not beneficial, " << "but was forced by a user.\n"; } } while (false) |
| 5791 | ChosenFactor.Cost >= ScalarCost.Cost) dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { if (ForceVectorization && !ChosenFactor .Width.isScalar() && ChosenFactor.Cost >= ScalarCost .Cost) dbgs() << "LV: Vectorization seems to be not beneficial, " << "but was forced by a user.\n"; } } while (false) |
| 5792 | << "LV: Vectorization seems to be not beneficial, "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { if (ForceVectorization && !ChosenFactor .Width.isScalar() && ChosenFactor.Cost >= ScalarCost .Cost) dbgs() << "LV: Vectorization seems to be not beneficial, " << "but was forced by a user.\n"; } } while (false) |
| 5793 | << "but was forced by a user.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { if (ForceVectorization && !ChosenFactor .Width.isScalar() && ChosenFactor.Cost >= ScalarCost .Cost) dbgs() << "LV: Vectorization seems to be not beneficial, " << "but was forced by a user.\n"; } } while (false); |
| 5794 | LLVM_DEBUG(dbgs() << "LV: Selecting VF: " << ChosenFactor.Width << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Selecting VF: " << ChosenFactor.Width << ".\n"; } } while (false); |
| 5795 | return ChosenFactor; |
| 5796 | } |
| 5797 | |
| 5798 | bool LoopVectorizationCostModel::isCandidateForEpilogueVectorization( |
| 5799 | const Loop &L, ElementCount VF) const { |
| 5800 | // Cross iteration phis such as reductions need special handling and are |
| 5801 | // currently unsupported. |
| 5802 | if (any_of(L.getHeader()->phis(), |
| 5803 | [&](PHINode &Phi) { return Legal->isFirstOrderRecurrence(&Phi); })) |
| 5804 | return false; |
| 5805 | |
| 5806 | // Phis with uses outside of the loop require special handling and are |
| 5807 | // currently unsupported. |
| 5808 | for (auto &Entry : Legal->getInductionVars()) { |
| 5809 | // Look for uses of the value of the induction at the last iteration. |
| 5810 | Value *PostInc = Entry.first->getIncomingValueForBlock(L.getLoopLatch()); |
| 5811 | for (User *U : PostInc->users()) |
| 5812 | if (!L.contains(cast<Instruction>(U))) |
| 5813 | return false; |
| 5814 | // Look for uses of penultimate value of the induction. |
| 5815 | for (User *U : Entry.first->users()) |
| 5816 | if (!L.contains(cast<Instruction>(U))) |
| 5817 | return false; |
| 5818 | } |
| 5819 | |
| 5820 | // Induction variables that are widened require special handling that is |
| 5821 | // currently not supported. |
| 5822 | if (any_of(Legal->getInductionVars(), [&](auto &Entry) { |
| 5823 | return !(this->isScalarAfterVectorization(Entry.first, VF) || |
| 5824 | this->isProfitableToScalarize(Entry.first, VF)); |
| 5825 | })) |
| 5826 | return false; |
| 5827 | |
| 5828 | // Epilogue vectorization code has not been auditted to ensure it handles |
| 5829 | // non-latch exits properly. It may be fine, but it needs auditted and |
| 5830 | // tested. |
| 5831 | if (L.getExitingBlock() != L.getLoopLatch()) |
| 5832 | return false; |
| 5833 | |
| 5834 | return true; |
| 5835 | } |
| 5836 | |
| 5837 | bool LoopVectorizationCostModel::isEpilogueVectorizationProfitable( |
| 5838 | const ElementCount VF) const { |
| 5839 | // FIXME: We need a much better cost-model to take different parameters such |
| 5840 | // as register pressure, code size increase and cost of extra branches into |
| 5841 | // account. For now we apply a very crude heuristic and only consider loops |
| 5842 | // with vectorization factors larger than a certain value. |
| 5843 | // We also consider epilogue vectorization unprofitable for targets that don't |
| 5844 | // consider interleaving beneficial (eg. MVE). |
| 5845 | if (TTI.getMaxInterleaveFactor(VF.getKnownMinValue()) <= 1) |
| 5846 | return false; |
| 5847 | // FIXME: We should consider changing the threshold for scalable |
| 5848 | // vectors to take VScaleForTuning into account. |
| 5849 | if (VF.getKnownMinValue() >= EpilogueVectorizationMinVF) |
| 5850 | return true; |
| 5851 | return false; |
| 5852 | } |
| 5853 | |
| 5854 | VectorizationFactor |
| 5855 | LoopVectorizationCostModel::selectEpilogueVectorizationFactor( |
| 5856 | const ElementCount MainLoopVF, const LoopVectorizationPlanner &LVP) { |
| 5857 | VectorizationFactor Result = VectorizationFactor::Disabled(); |
| 5858 | if (!EnableEpilogueVectorization) { |
| 5859 | LLVM_DEBUG(dbgs() << "LEV: Epilogue vectorization is disabled.\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization is disabled.\n" ;; } } while (false); |
| 5860 | return Result; |
| 5861 | } |
| 5862 | |
| 5863 | if (!isScalarEpilogueAllowed()) { |
| 5864 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Unable to vectorize epilogue because no epilogue is " "allowed.\n";; } } while (false) |
| 5865 | dbgs() << "LEV: Unable to vectorize epilogue because no epilogue is "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Unable to vectorize epilogue because no epilogue is " "allowed.\n";; } } while (false) |
| 5866 | "allowed.\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Unable to vectorize epilogue because no epilogue is " "allowed.\n";; } } while (false); |
| 5867 | return Result; |
| 5868 | } |
| 5869 | |
| 5870 | // Not really a cost consideration, but check for unsupported cases here to |
| 5871 | // simplify the logic. |
| 5872 | if (!isCandidateForEpilogueVectorization(*TheLoop, MainLoopVF)) { |
| 5873 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Unable to vectorize epilogue because the loop is " "not a supported candidate.\n";; } } while (false) |
| 5874 | dbgs() << "LEV: Unable to vectorize epilogue because the loop is "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Unable to vectorize epilogue because the loop is " "not a supported candidate.\n";; } } while (false) |
| 5875 | "not a supported candidate.\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Unable to vectorize epilogue because the loop is " "not a supported candidate.\n";; } } while (false); |
| 5876 | return Result; |
| 5877 | } |
| 5878 | |
| 5879 | if (EpilogueVectorizationForceVF > 1) { |
| 5880 | LLVM_DEBUG(dbgs() << "LEV: Epilogue vectorization factor is forced.\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization factor is forced.\n" ;; } } while (false); |
| 5881 | ElementCount ForcedEC = ElementCount::getFixed(EpilogueVectorizationForceVF); |
| 5882 | if (LVP.hasPlanWithVF(ForcedEC)) |
| 5883 | return {ForcedEC, 0}; |
| 5884 | else { |
| 5885 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization forced factor is not viable.\n" ;; } } while (false) |
| 5886 | dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization forced factor is not viable.\n" ;; } } while (false) |
| 5887 | << "LEV: Epilogue vectorization forced factor is not viable.\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization forced factor is not viable.\n" ;; } } while (false); |
| 5888 | return Result; |
| 5889 | } |
| 5890 | } |
| 5891 | |
| 5892 | if (TheLoop->getHeader()->getParent()->hasOptSize() || |
| 5893 | TheLoop->getHeader()->getParent()->hasMinSize()) { |
| 5894 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization skipped due to opt for size.\n" ;; } } while (false) |
| 5895 | dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization skipped due to opt for size.\n" ;; } } while (false) |
| 5896 | << "LEV: Epilogue vectorization skipped due to opt for size.\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization skipped due to opt for size.\n" ;; } } while (false); |
| 5897 | return Result; |
| 5898 | } |
| 5899 | |
| 5900 | if (!isEpilogueVectorizationProfitable(MainLoopVF)) { |
| 5901 | LLVM_DEBUG(dbgs() << "LEV: Epilogue vectorization is not profitable for "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization is not profitable for " "this loop\n"; } } while (false) |
| 5902 | "this loop\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Epilogue vectorization is not profitable for " "this loop\n"; } } while (false); |
| 5903 | return Result; |
| 5904 | } |
| 5905 | |
| 5906 | // If MainLoopVF = vscale x 2, and vscale is expected to be 4, then we know |
| 5907 | // the main loop handles 8 lanes per iteration. We could still benefit from |
| 5908 | // vectorizing the epilogue loop with VF=4. |
| 5909 | ElementCount EstimatedRuntimeVF = MainLoopVF; |
| 5910 | if (MainLoopVF.isScalable()) { |
| 5911 | EstimatedRuntimeVF = ElementCount::getFixed(MainLoopVF.getKnownMinValue()); |
| 5912 | if (Optional<unsigned> VScale = getVScaleForTuning()) |
| 5913 | EstimatedRuntimeVF *= VScale.getValue(); |
| 5914 | } |
| 5915 | |
| 5916 | for (auto &NextVF : ProfitableVFs) |
| 5917 | if (((!NextVF.Width.isScalable() && MainLoopVF.isScalable() && |
| 5918 | ElementCount::isKnownLT(NextVF.Width, EstimatedRuntimeVF)) || |
| 5919 | ElementCount::isKnownLT(NextVF.Width, MainLoopVF)) && |
| 5920 | (Result.Width.isScalar() || isMoreProfitable(NextVF, Result)) && |
| 5921 | LVP.hasPlanWithVF(NextVF.Width)) |
| 5922 | Result = NextVF; |
| 5923 | |
| 5924 | if (Result != VectorizationFactor::Disabled()) |
| 5925 | LLVM_DEBUG(dbgs() << "LEV: Vectorizing epilogue loop with VF = "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Vectorizing epilogue loop with VF = " << Result.Width << "\n";; } } while (false) |
| 5926 | << Result.Width << "\n";)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LEV: Vectorizing epilogue loop with VF = " << Result.Width << "\n";; } } while (false); |
| 5927 | return Result; |
| 5928 | } |
| 5929 | |
| 5930 | std::pair<unsigned, unsigned> |
| 5931 | LoopVectorizationCostModel::getSmallestAndWidestTypes() { |
| 5932 | unsigned MinWidth = -1U; |
| 5933 | unsigned MaxWidth = 8; |
| 5934 | const DataLayout &DL = TheFunction->getParent()->getDataLayout(); |
| 5935 | // For in-loop reductions, no element types are added to ElementTypesInLoop |
| 5936 | // if there are no loads/stores in the loop. In this case, check through the |
| 5937 | // reduction variables to determine the maximum width. |
| 5938 | if (ElementTypesInLoop.empty() && !Legal->getReductionVars().empty()) { |
| 5939 | // Reset MaxWidth so that we can find the smallest type used by recurrences |
| 5940 | // in the loop. |
| 5941 | MaxWidth = -1U; |
| 5942 | for (auto &PhiDescriptorPair : Legal->getReductionVars()) { |
| 5943 | const RecurrenceDescriptor &RdxDesc = PhiDescriptorPair.second; |
| 5944 | // When finding the min width used by the recurrence we need to account |
| 5945 | // for casts on the input operands of the recurrence. |
| 5946 | MaxWidth = std::min<unsigned>( |
| 5947 | MaxWidth, std::min<unsigned>( |
| 5948 | RdxDesc.getMinWidthCastToRecurrenceTypeInBits(), |
| 5949 | RdxDesc.getRecurrenceType()->getScalarSizeInBits())); |
| 5950 | } |
| 5951 | } else { |
| 5952 | for (Type *T : ElementTypesInLoop) { |
| 5953 | MinWidth = std::min<unsigned>( |
| 5954 | MinWidth, DL.getTypeSizeInBits(T->getScalarType()).getFixedSize()); |
| 5955 | MaxWidth = std::max<unsigned>( |
| 5956 | MaxWidth, DL.getTypeSizeInBits(T->getScalarType()).getFixedSize()); |
| 5957 | } |
| 5958 | } |
| 5959 | return {MinWidth, MaxWidth}; |
| 5960 | } |
| 5961 | |
| 5962 | void LoopVectorizationCostModel::collectElementTypesForWidening() { |
| 5963 | ElementTypesInLoop.clear(); |
| 5964 | // For each block. |
| 5965 | for (BasicBlock *BB : TheLoop->blocks()) { |
| 5966 | // For each instruction in the loop. |
| 5967 | for (Instruction &I : BB->instructionsWithoutDebug()) { |
| 5968 | Type *T = I.getType(); |
| 5969 | |
| 5970 | // Skip ignored values. |
| 5971 | if (ValuesToIgnore.count(&I)) |
| 5972 | continue; |
| 5973 | |
| 5974 | // Only examine Loads, Stores and PHINodes. |
| 5975 | if (!isa<LoadInst>(I) && !isa<StoreInst>(I) && !isa<PHINode>(I)) |
| 5976 | continue; |
| 5977 | |
| 5978 | // Examine PHI nodes that are reduction variables. Update the type to |
| 5979 | // account for the recurrence type. |
| 5980 | if (auto *PN = dyn_cast<PHINode>(&I)) { |
| 5981 | if (!Legal->isReductionVariable(PN)) |
| 5982 | continue; |
| 5983 | const RecurrenceDescriptor &RdxDesc = |
| 5984 | Legal->getReductionVars().find(PN)->second; |
| 5985 | if (PreferInLoopReductions || useOrderedReductions(RdxDesc) || |
| 5986 | TTI.preferInLoopReduction(RdxDesc.getOpcode(), |
| 5987 | RdxDesc.getRecurrenceType(), |
| 5988 | TargetTransformInfo::ReductionFlags())) |
| 5989 | continue; |
| 5990 | T = RdxDesc.getRecurrenceType(); |
| 5991 | } |
| 5992 | |
| 5993 | // Examine the stored values. |
| 5994 | if (auto *ST = dyn_cast<StoreInst>(&I)) |
| 5995 | T = ST->getValueOperand()->getType(); |
| 5996 | |
| 5997 | assert(T->isSized() &&(static_cast <bool> (T->isSized() && "Expected the load/store/recurrence type to be sized" ) ? void (0) : __assert_fail ("T->isSized() && \"Expected the load/store/recurrence type to be sized\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5998, __extension__ __PRETTY_FUNCTION__)) |
| 5998 | "Expected the load/store/recurrence type to be sized")(static_cast <bool> (T->isSized() && "Expected the load/store/recurrence type to be sized" ) ? void (0) : __assert_fail ("T->isSized() && \"Expected the load/store/recurrence type to be sized\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 5998, __extension__ __PRETTY_FUNCTION__)); |
| 5999 | |
| 6000 | ElementTypesInLoop.insert(T); |
| 6001 | } |
| 6002 | } |
| 6003 | } |
| 6004 | |
| 6005 | unsigned LoopVectorizationCostModel::selectInterleaveCount(ElementCount VF, |
| 6006 | unsigned LoopCost) { |
| 6007 | // -- The interleave heuristics -- |
| 6008 | // We interleave the loop in order to expose ILP and reduce the loop overhead. |
| 6009 | // There are many micro-architectural considerations that we can't predict |
| 6010 | // at this level. For example, frontend pressure (on decode or fetch) due to |
| 6011 | // code size, or the number and capabilities of the execution ports. |
| 6012 | // |
| 6013 | // We use the following heuristics to select the interleave count: |
| 6014 | // 1. If the code has reductions, then we interleave to break the cross |
| 6015 | // iteration dependency. |
| 6016 | // 2. If the loop is really small, then we interleave to reduce the loop |
| 6017 | // overhead. |
| 6018 | // 3. We don't interleave if we think that we will spill registers to memory |
| 6019 | // due to the increased register pressure. |
| 6020 | |
| 6021 | if (!isScalarEpilogueAllowed()) |
| 6022 | return 1; |
| 6023 | |
| 6024 | // We used the distance for the interleave count. |
| 6025 | if (Legal->getMaxSafeDepDistBytes() != -1U) |
| 6026 | return 1; |
| 6027 | |
| 6028 | auto BestKnownTC = getSmallBestKnownTC(*PSE.getSE(), TheLoop); |
| 6029 | const bool HasReductions = !Legal->getReductionVars().empty(); |
| 6030 | // Do not interleave loops with a relatively small known or estimated trip |
| 6031 | // count. But we will interleave when InterleaveSmallLoopScalarReduction is |
| 6032 | // enabled, and the code has scalar reductions(HasReductions && VF = 1), |
| 6033 | // because with the above conditions interleaving can expose ILP and break |
| 6034 | // cross iteration dependences for reductions. |
| 6035 | if (BestKnownTC && (*BestKnownTC < TinyTripCountInterleaveThreshold) && |
| 6036 | !(InterleaveSmallLoopScalarReduction && HasReductions && VF.isScalar())) |
| 6037 | return 1; |
| 6038 | |
| 6039 | RegisterUsage R = calculateRegisterUsage({VF})[0]; |
| 6040 | // We divide by these constants so assume that we have at least one |
| 6041 | // instruction that uses at least one register. |
| 6042 | for (auto& pair : R.MaxLocalUsers) { |
| 6043 | pair.second = std::max(pair.second, 1U); |
| 6044 | } |
| 6045 | |
| 6046 | // We calculate the interleave count using the following formula. |
| 6047 | // Subtract the number of loop invariants from the number of available |
| 6048 | // registers. These registers are used by all of the interleaved instances. |
| 6049 | // Next, divide the remaining registers by the number of registers that is |
| 6050 | // required by the loop, in order to estimate how many parallel instances |
| 6051 | // fit without causing spills. All of this is rounded down if necessary to be |
| 6052 | // a power of two. We want power of two interleave count to simplify any |
| 6053 | // addressing operations or alignment considerations. |
| 6054 | // We also want power of two interleave counts to ensure that the induction |
| 6055 | // variable of the vector loop wraps to zero, when tail is folded by masking; |
| 6056 | // this currently happens when OptForSize, in which case IC is set to 1 above. |
| 6057 | unsigned IC = UINT_MAX(2147483647 *2U +1U); |
| 6058 | |
| 6059 | for (auto& pair : R.MaxLocalUsers) { |
| 6060 | unsigned TargetNumRegisters = TTI.getNumberOfRegisters(pair.first); |
| 6061 | LLVM_DEBUG(dbgs() << "LV: The target has " << TargetNumRegistersdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The target has " << TargetNumRegisters << " registers of " << TTI.getRegisterClassName (pair.first) << " register class\n"; } } while (false) |
| 6062 | << " registers of "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The target has " << TargetNumRegisters << " registers of " << TTI.getRegisterClassName (pair.first) << " register class\n"; } } while (false) |
| 6063 | << TTI.getRegisterClassName(pair.first) << " register class\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: The target has " << TargetNumRegisters << " registers of " << TTI.getRegisterClassName (pair.first) << " register class\n"; } } while (false); |
| 6064 | if (VF.isScalar()) { |
| 6065 | if (ForceTargetNumScalarRegs.getNumOccurrences() > 0) |
| 6066 | TargetNumRegisters = ForceTargetNumScalarRegs; |
| 6067 | } else { |
| 6068 | if (ForceTargetNumVectorRegs.getNumOccurrences() > 0) |
| 6069 | TargetNumRegisters = ForceTargetNumVectorRegs; |
| 6070 | } |
| 6071 | unsigned MaxLocalUsers = pair.second; |
| 6072 | unsigned LoopInvariantRegs = 0; |
| 6073 | if (R.LoopInvariantRegs.find(pair.first) != R.LoopInvariantRegs.end()) |
| 6074 | LoopInvariantRegs = R.LoopInvariantRegs[pair.first]; |
| 6075 | |
| 6076 | unsigned TmpIC = PowerOf2Floor((TargetNumRegisters - LoopInvariantRegs) / MaxLocalUsers); |
| 6077 | // Don't count the induction variable as interleaved. |
| 6078 | if (EnableIndVarRegisterHeur) { |
| 6079 | TmpIC = |
| 6080 | PowerOf2Floor((TargetNumRegisters - LoopInvariantRegs - 1) / |
| 6081 | std::max(1U, (MaxLocalUsers - 1))); |
| 6082 | } |
| 6083 | |
| 6084 | IC = std::min(IC, TmpIC); |
| 6085 | } |
| 6086 | |
| 6087 | // Clamp the interleave ranges to reasonable counts. |
| 6088 | unsigned MaxInterleaveCount = |
| 6089 | TTI.getMaxInterleaveFactor(VF.getKnownMinValue()); |
| 6090 | |
| 6091 | // Check if the user has overridden the max. |
| 6092 | if (VF.isScalar()) { |
| 6093 | if (ForceTargetMaxScalarInterleaveFactor.getNumOccurrences() > 0) |
| 6094 | MaxInterleaveCount = ForceTargetMaxScalarInterleaveFactor; |
| 6095 | } else { |
| 6096 | if (ForceTargetMaxVectorInterleaveFactor.getNumOccurrences() > 0) |
| 6097 | MaxInterleaveCount = ForceTargetMaxVectorInterleaveFactor; |
| 6098 | } |
| 6099 | |
| 6100 | // If trip count is known or estimated compile time constant, limit the |
| 6101 | // interleave count to be less than the trip count divided by VF, provided it |
| 6102 | // is at least 1. |
| 6103 | // |
| 6104 | // For scalable vectors we can't know if interleaving is beneficial. It may |
| 6105 | // not be beneficial for small loops if none of the lanes in the second vector |
| 6106 | // iterations is enabled. However, for larger loops, there is likely to be a |
| 6107 | // similar benefit as for fixed-width vectors. For now, we choose to leave |
| 6108 | // the InterleaveCount as if vscale is '1', although if some information about |
| 6109 | // the vector is known (e.g. min vector size), we can make a better decision. |
| 6110 | if (BestKnownTC) { |
| 6111 | MaxInterleaveCount = |
| 6112 | std::min(*BestKnownTC / VF.getKnownMinValue(), MaxInterleaveCount); |
| 6113 | // Make sure MaxInterleaveCount is greater than 0. |
| 6114 | MaxInterleaveCount = std::max(1u, MaxInterleaveCount); |
| 6115 | } |
| 6116 | |
| 6117 | assert(MaxInterleaveCount > 0 &&(static_cast <bool> (MaxInterleaveCount > 0 && "Maximum interleave count must be greater than 0") ? void (0 ) : __assert_fail ("MaxInterleaveCount > 0 && \"Maximum interleave count must be greater than 0\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6118, __extension__ __PRETTY_FUNCTION__)) |
| 6118 | "Maximum interleave count must be greater than 0")(static_cast <bool> (MaxInterleaveCount > 0 && "Maximum interleave count must be greater than 0") ? void (0 ) : __assert_fail ("MaxInterleaveCount > 0 && \"Maximum interleave count must be greater than 0\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6118, __extension__ __PRETTY_FUNCTION__)); |
| 6119 | |
| 6120 | // Clamp the calculated IC to be between the 1 and the max interleave count |
| 6121 | // that the target and trip count allows. |
| 6122 | if (IC > MaxInterleaveCount) |
| 6123 | IC = MaxInterleaveCount; |
| 6124 | else |
| 6125 | // Make sure IC is greater than 0. |
| 6126 | IC = std::max(1u, IC); |
| 6127 | |
| 6128 | assert(IC > 0 && "Interleave count must be greater than 0.")(static_cast <bool> (IC > 0 && "Interleave count must be greater than 0." ) ? void (0) : __assert_fail ("IC > 0 && \"Interleave count must be greater than 0.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6128, __extension__ __PRETTY_FUNCTION__)); |
| 6129 | |
| 6130 | // If we did not calculate the cost for VF (because the user selected the VF) |
| 6131 | // then we calculate the cost of VF here. |
| 6132 | if (LoopCost == 0) { |
| 6133 | InstructionCost C = expectedCost(VF).first; |
| 6134 | assert(C.isValid() && "Expected to have chosen a VF with valid cost")(static_cast <bool> (C.isValid() && "Expected to have chosen a VF with valid cost" ) ? void (0) : __assert_fail ("C.isValid() && \"Expected to have chosen a VF with valid cost\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6134, __extension__ __PRETTY_FUNCTION__)); |
| 6135 | LoopCost = *C.getValue(); |
| 6136 | } |
| 6137 | |
| 6138 | assert(LoopCost && "Non-zero loop cost expected")(static_cast <bool> (LoopCost && "Non-zero loop cost expected" ) ? void (0) : __assert_fail ("LoopCost && \"Non-zero loop cost expected\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6138, __extension__ __PRETTY_FUNCTION__)); |
| 6139 | |
| 6140 | // Interleave if we vectorized this loop and there is a reduction that could |
| 6141 | // benefit from interleaving. |
| 6142 | if (VF.isVector() && HasReductions) { |
| 6143 | LLVM_DEBUG(dbgs() << "LV: Interleaving because of reductions.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving because of reductions.\n" ; } } while (false); |
| 6144 | return IC; |
| 6145 | } |
| 6146 | |
| 6147 | // Note that if we've already vectorized the loop we will have done the |
| 6148 | // runtime check and so interleaving won't require further checks. |
| 6149 | bool InterleavingRequiresRuntimePointerCheck = |
| 6150 | (VF.isScalar() && Legal->getRuntimePointerChecking()->Need); |
| 6151 | |
| 6152 | // We want to interleave small loops in order to reduce the loop overhead and |
| 6153 | // potentially expose ILP opportunities. |
| 6154 | LLVM_DEBUG(dbgs() << "LV: Loop cost is " << LoopCost << '\n'do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop cost is " << LoopCost << '\n' << "LV: IC is " << IC << '\n' << "LV: VF is " << VF << '\n'; } } while (false) |
| 6155 | << "LV: IC is " << IC << '\n'do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop cost is " << LoopCost << '\n' << "LV: IC is " << IC << '\n' << "LV: VF is " << VF << '\n'; } } while (false) |
| 6156 | << "LV: VF is " << VF << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop cost is " << LoopCost << '\n' << "LV: IC is " << IC << '\n' << "LV: VF is " << VF << '\n'; } } while (false); |
| 6157 | const bool AggressivelyInterleaveReductions = |
| 6158 | TTI.enableAggressiveInterleaving(HasReductions); |
| 6159 | if (!InterleavingRequiresRuntimePointerCheck && LoopCost < SmallLoopCost) { |
| 6160 | // We assume that the cost overhead is 1 and we use the cost model |
| 6161 | // to estimate the cost of the loop and interleave until the cost of the |
| 6162 | // loop overhead is about 5% of the cost of the loop. |
| 6163 | unsigned SmallIC = |
| 6164 | std::min(IC, (unsigned)PowerOf2Floor(SmallLoopCost / LoopCost)); |
| 6165 | |
| 6166 | // Interleave until store/load ports (estimated by max interleave count) are |
| 6167 | // saturated. |
| 6168 | unsigned NumStores = Legal->getNumStores(); |
| 6169 | unsigned NumLoads = Legal->getNumLoads(); |
| 6170 | unsigned StoresIC = IC / (NumStores ? NumStores : 1); |
| 6171 | unsigned LoadsIC = IC / (NumLoads ? NumLoads : 1); |
| 6172 | |
| 6173 | // There is little point in interleaving for reductions containing selects |
| 6174 | // and compares when VF=1 since it may just create more overhead than it's |
| 6175 | // worth for loops with small trip counts. This is because we still have to |
| 6176 | // do the final reduction after the loop. |
| 6177 | bool HasSelectCmpReductions = |
| 6178 | HasReductions && |
| 6179 | any_of(Legal->getReductionVars(), [&](auto &Reduction) -> bool { |
| 6180 | const RecurrenceDescriptor &RdxDesc = Reduction.second; |
| 6181 | return RecurrenceDescriptor::isSelectCmpRecurrenceKind( |
| 6182 | RdxDesc.getRecurrenceKind()); |
| 6183 | }); |
| 6184 | if (HasSelectCmpReductions) { |
| 6185 | LLVM_DEBUG(dbgs() << "LV: Not interleaving select-cmp reductions.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not interleaving select-cmp reductions.\n" ; } } while (false); |
| 6186 | return 1; |
| 6187 | } |
| 6188 | |
| 6189 | // If we have a scalar reduction (vector reductions are already dealt with |
| 6190 | // by this point), we can increase the critical path length if the loop |
| 6191 | // we're interleaving is inside another loop. For tree-wise reductions |
| 6192 | // set the limit to 2, and for ordered reductions it's best to disable |
| 6193 | // interleaving entirely. |
| 6194 | if (HasReductions && TheLoop->getLoopDepth() > 1) { |
| 6195 | bool HasOrderedReductions = |
| 6196 | any_of(Legal->getReductionVars(), [&](auto &Reduction) -> bool { |
| 6197 | const RecurrenceDescriptor &RdxDesc = Reduction.second; |
| 6198 | return RdxDesc.isOrdered(); |
| 6199 | }); |
| 6200 | if (HasOrderedReductions) { |
| 6201 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not interleaving scalar ordered reductions.\n" ; } } while (false) |
| 6202 | dbgs() << "LV: Not interleaving scalar ordered reductions.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not interleaving scalar ordered reductions.\n" ; } } while (false); |
| 6203 | return 1; |
| 6204 | } |
| 6205 | |
| 6206 | unsigned F = static_cast<unsigned>(MaxNestedScalarReductionIC); |
| 6207 | SmallIC = std::min(SmallIC, F); |
| 6208 | StoresIC = std::min(StoresIC, F); |
| 6209 | LoadsIC = std::min(LoadsIC, F); |
| 6210 | } |
| 6211 | |
| 6212 | if (EnableLoadStoreRuntimeInterleave && |
| 6213 | std::max(StoresIC, LoadsIC) > SmallIC) { |
| 6214 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving to saturate store or load ports.\n" ; } } while (false) |
| 6215 | dbgs() << "LV: Interleaving to saturate store or load ports.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving to saturate store or load ports.\n" ; } } while (false); |
| 6216 | return std::max(StoresIC, LoadsIC); |
| 6217 | } |
| 6218 | |
| 6219 | // If there are scalar reductions and TTI has enabled aggressive |
| 6220 | // interleaving for reductions, we will interleave to expose ILP. |
| 6221 | if (InterleaveSmallLoopScalarReduction && VF.isScalar() && |
| 6222 | AggressivelyInterleaveReductions) { |
| 6223 | LLVM_DEBUG(dbgs() << "LV: Interleaving to expose ILP.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving to expose ILP.\n" ; } } while (false); |
| 6224 | // Interleave no less than SmallIC but not as aggressive as the normal IC |
| 6225 | // to satisfy the rare situation when resources are too limited. |
| 6226 | return std::max(IC / 2, SmallIC); |
| 6227 | } else { |
| 6228 | LLVM_DEBUG(dbgs() << "LV: Interleaving to reduce branch cost.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving to reduce branch cost.\n" ; } } while (false); |
| 6229 | return SmallIC; |
| 6230 | } |
| 6231 | } |
| 6232 | |
| 6233 | // Interleave if this is a large loop (small loops are already dealt with by |
| 6234 | // this point) that could benefit from interleaving. |
| 6235 | if (AggressivelyInterleaveReductions) { |
| 6236 | LLVM_DEBUG(dbgs() << "LV: Interleaving to expose ILP.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving to expose ILP.\n" ; } } while (false); |
| 6237 | return IC; |
| 6238 | } |
| 6239 | |
| 6240 | LLVM_DEBUG(dbgs() << "LV: Not Interleaving.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not Interleaving.\n" ; } } while (false); |
| 6241 | return 1; |
| 6242 | } |
| 6243 | |
| 6244 | SmallVector<LoopVectorizationCostModel::RegisterUsage, 8> |
| 6245 | LoopVectorizationCostModel::calculateRegisterUsage(ArrayRef<ElementCount> VFs) { |
| 6246 | // This function calculates the register usage by measuring the highest number |
| 6247 | // of values that are alive at a single location. Obviously, this is a very |
| 6248 | // rough estimation. We scan the loop in a topological order in order and |
| 6249 | // assign a number to each instruction. We use RPO to ensure that defs are |
| 6250 | // met before their users. We assume that each instruction that has in-loop |
| 6251 | // users starts an interval. We record every time that an in-loop value is |
| 6252 | // used, so we have a list of the first and last occurrences of each |
| 6253 | // instruction. Next, we transpose this data structure into a multi map that |
| 6254 | // holds the list of intervals that *end* at a specific location. This multi |
| 6255 | // map allows us to perform a linear search. We scan the instructions linearly |
| 6256 | // and record each time that a new interval starts, by placing it in a set. |
| 6257 | // If we find this value in the multi-map then we remove it from the set. |
| 6258 | // The max register usage is the maximum size of the set. |
| 6259 | // We also search for instructions that are defined outside the loop, but are |
| 6260 | // used inside the loop. We need this number separately from the max-interval |
| 6261 | // usage number because when we unroll, loop-invariant values do not take |
| 6262 | // more register. |
| 6263 | LoopBlocksDFS DFS(TheLoop); |
| 6264 | DFS.perform(LI); |
| 6265 | |
| 6266 | RegisterUsage RU; |
| 6267 | |
| 6268 | // Each 'key' in the map opens a new interval. The values |
| 6269 | // of the map are the index of the 'last seen' usage of the |
| 6270 | // instruction that is the key. |
| 6271 | using IntervalMap = DenseMap<Instruction *, unsigned>; |
| 6272 | |
| 6273 | // Maps instruction to its index. |
| 6274 | SmallVector<Instruction *, 64> IdxToInstr; |
| 6275 | // Marks the end of each interval. |
| 6276 | IntervalMap EndPoint; |
| 6277 | // Saves the list of instruction indices that are used in the loop. |
| 6278 | SmallPtrSet<Instruction *, 8> Ends; |
| 6279 | // Saves the list of values that are used in the loop but are |
| 6280 | // defined outside the loop, such as arguments and constants. |
| 6281 | SmallPtrSet<Value *, 8> LoopInvariants; |
| 6282 | |
| 6283 | for (BasicBlock *BB : make_range(DFS.beginRPO(), DFS.endRPO())) { |
| 6284 | for (Instruction &I : BB->instructionsWithoutDebug()) { |
| 6285 | IdxToInstr.push_back(&I); |
| 6286 | |
| 6287 | // Save the end location of each USE. |
| 6288 | for (Value *U : I.operands()) { |
| 6289 | auto *Instr = dyn_cast<Instruction>(U); |
| 6290 | |
| 6291 | // Ignore non-instruction values such as arguments, constants, etc. |
| 6292 | if (!Instr) |
| 6293 | continue; |
| 6294 | |
| 6295 | // If this instruction is outside the loop then record it and continue. |
| 6296 | if (!TheLoop->contains(Instr)) { |
| 6297 | LoopInvariants.insert(Instr); |
| 6298 | continue; |
| 6299 | } |
| 6300 | |
| 6301 | // Overwrite previous end points. |
| 6302 | EndPoint[Instr] = IdxToInstr.size(); |
| 6303 | Ends.insert(Instr); |
| 6304 | } |
| 6305 | } |
| 6306 | } |
| 6307 | |
| 6308 | // Saves the list of intervals that end with the index in 'key'. |
| 6309 | using InstrList = SmallVector<Instruction *, 2>; |
| 6310 | DenseMap<unsigned, InstrList> TransposeEnds; |
| 6311 | |
| 6312 | // Transpose the EndPoints to a list of values that end at each index. |
| 6313 | for (auto &Interval : EndPoint) |
| 6314 | TransposeEnds[Interval.second].push_back(Interval.first); |
| 6315 | |
| 6316 | SmallPtrSet<Instruction *, 8> OpenIntervals; |
| 6317 | SmallVector<RegisterUsage, 8> RUs(VFs.size()); |
| 6318 | SmallVector<SmallMapVector<unsigned, unsigned, 4>, 8> MaxUsages(VFs.size()); |
| 6319 | |
| 6320 | LLVM_DEBUG(dbgs() << "LV(REG): Calculating max register usage:\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV(REG): Calculating max register usage:\n" ; } } while (false); |
| 6321 | |
| 6322 | // A lambda that gets the register usage for the given type and VF. |
| 6323 | const auto &TTICapture = TTI; |
| 6324 | auto GetRegUsage = [&TTICapture](Type *Ty, ElementCount VF) -> unsigned { |
| 6325 | if (Ty->isTokenTy() || !VectorType::isValidElementType(Ty)) |
| 6326 | return 0; |
| 6327 | InstructionCost::CostType RegUsage = |
| 6328 | *TTICapture.getRegUsageForType(VectorType::get(Ty, VF)).getValue(); |
| 6329 | assert(RegUsage >= 0 && RegUsage <= std::numeric_limits<unsigned>::max() &&(static_cast <bool> (RegUsage >= 0 && RegUsage <= std::numeric_limits<unsigned>::max() && "Nonsensical values for register usage." ) ? void (0) : __assert_fail ("RegUsage >= 0 && RegUsage <= std::numeric_limits<unsigned>::max() && \"Nonsensical values for register usage.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6330, __extension__ __PRETTY_FUNCTION__)) |
| 6330 | "Nonsensical values for register usage.")(static_cast <bool> (RegUsage >= 0 && RegUsage <= std::numeric_limits<unsigned>::max() && "Nonsensical values for register usage." ) ? void (0) : __assert_fail ("RegUsage >= 0 && RegUsage <= std::numeric_limits<unsigned>::max() && \"Nonsensical values for register usage.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6330, __extension__ __PRETTY_FUNCTION__)); |
| 6331 | return RegUsage; |
| 6332 | }; |
| 6333 | |
| 6334 | for (unsigned int i = 0, s = IdxToInstr.size(); i < s; ++i) { |
| 6335 | Instruction *I = IdxToInstr[i]; |
| 6336 | |
| 6337 | // Remove all of the instructions that end at this location. |
| 6338 | InstrList &List = TransposeEnds[i]; |
| 6339 | for (Instruction *ToRemove : List) |
| 6340 | OpenIntervals.erase(ToRemove); |
| 6341 | |
| 6342 | // Ignore instructions that are never used within the loop. |
| 6343 | if (!Ends.count(I)) |
| 6344 | continue; |
| 6345 | |
| 6346 | // Skip ignored values. |
| 6347 | if (ValuesToIgnore.count(I)) |
| 6348 | continue; |
| 6349 | |
| 6350 | // For each VF find the maximum usage of registers. |
| 6351 | for (unsigned j = 0, e = VFs.size(); j < e; ++j) { |
| 6352 | // Count the number of live intervals. |
| 6353 | SmallMapVector<unsigned, unsigned, 4> RegUsage; |
| 6354 | |
| 6355 | if (VFs[j].isScalar()) { |
| 6356 | for (auto Inst : OpenIntervals) { |
| 6357 | unsigned ClassID = TTI.getRegisterClassForType(false, Inst->getType()); |
| 6358 | if (RegUsage.find(ClassID) == RegUsage.end()) |
| 6359 | RegUsage[ClassID] = 1; |
| 6360 | else |
| 6361 | RegUsage[ClassID] += 1; |
| 6362 | } |
| 6363 | } else { |
| 6364 | collectUniformsAndScalars(VFs[j]); |
| 6365 | for (auto Inst : OpenIntervals) { |
| 6366 | // Skip ignored values for VF > 1. |
| 6367 | if (VecValuesToIgnore.count(Inst)) |
| 6368 | continue; |
| 6369 | if (isScalarAfterVectorization(Inst, VFs[j])) { |
| 6370 | unsigned ClassID = TTI.getRegisterClassForType(false, Inst->getType()); |
| 6371 | if (RegUsage.find(ClassID) == RegUsage.end()) |
| 6372 | RegUsage[ClassID] = 1; |
| 6373 | else |
| 6374 | RegUsage[ClassID] += 1; |
| 6375 | } else { |
| 6376 | unsigned ClassID = TTI.getRegisterClassForType(true, Inst->getType()); |
| 6377 | if (RegUsage.find(ClassID) == RegUsage.end()) |
| 6378 | RegUsage[ClassID] = GetRegUsage(Inst->getType(), VFs[j]); |
| 6379 | else |
| 6380 | RegUsage[ClassID] += GetRegUsage(Inst->getType(), VFs[j]); |
| 6381 | } |
| 6382 | } |
| 6383 | } |
| 6384 | |
| 6385 | for (auto& pair : RegUsage) { |
| 6386 | if (MaxUsages[j].find(pair.first) != MaxUsages[j].end()) |
| 6387 | MaxUsages[j][pair.first] = std::max(MaxUsages[j][pair.first], pair.second); |
| 6388 | else |
| 6389 | MaxUsages[j][pair.first] = pair.second; |
| 6390 | } |
| 6391 | } |
| 6392 | |
| 6393 | LLVM_DEBUG(dbgs() << "LV(REG): At #" << i << " Interval # "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV(REG): At #" << i << " Interval # " << OpenIntervals.size() << '\n'; } } while (false) |
| 6394 | << OpenIntervals.size() << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV(REG): At #" << i << " Interval # " << OpenIntervals.size() << '\n'; } } while (false); |
| 6395 | |
| 6396 | // Add the current instruction to the list of open intervals. |
| 6397 | OpenIntervals.insert(I); |
| 6398 | } |
| 6399 | |
| 6400 | for (unsigned i = 0, e = VFs.size(); i < e; ++i) { |
| 6401 | SmallMapVector<unsigned, unsigned, 4> Invariant; |
| 6402 | |
| 6403 | for (auto Inst : LoopInvariants) { |
| 6404 | unsigned Usage = |
| 6405 | VFs[i].isScalar() ? 1 : GetRegUsage(Inst->getType(), VFs[i]); |
| 6406 | unsigned ClassID = |
| 6407 | TTI.getRegisterClassForType(VFs[i].isVector(), Inst->getType()); |
| 6408 | if (Invariant.find(ClassID) == Invariant.end()) |
| 6409 | Invariant[ClassID] = Usage; |
| 6410 | else |
| 6411 | Invariant[ClassID] += Usage; |
| 6412 | } |
| 6413 | |
| 6414 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6415 | dbgs() << "LV(REG): VF = " << VFs[i] << '\n';do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6416 | dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6417 | << " item\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6418 | for (const auto &pair : MaxUsages[i]) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6419 | dbgs() << "LV(REG): RegisterClass: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6420 | << TTI.getRegisterClassName(pair.first) << ", " << pair.seconddo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6421 | << " registers\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6422 | }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6423 | dbgs() << "LV(REG): Found invariant usage: " << Invariant.size()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6424 | << " item\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6425 | for (const auto &pair : Invariant) {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6426 | dbgs() << "LV(REG): RegisterClass: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6427 | << TTI.getRegisterClassName(pair.first) << ", " << pair.seconddo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6428 | << " registers\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6429 | }do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false) |
| 6430 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "LV(REG): VF = " << VFs[i] << '\n'; dbgs() << "LV(REG): Found max usage: " << MaxUsages[i].size() << " item\n"; for (const auto &pair : MaxUsages[i]) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } dbgs() << "LV(REG): Found invariant usage: " << Invariant.size() << " item\n"; for (const auto &pair : Invariant) { dbgs() << "LV(REG): RegisterClass: " << TTI.getRegisterClassName(pair.first) << ", " << pair.second << " registers\n"; } }; } } while (false); |
| 6431 | |
| 6432 | RU.LoopInvariantRegs = Invariant; |
| 6433 | RU.MaxLocalUsers = MaxUsages[i]; |
| 6434 | RUs[i] = RU; |
| 6435 | } |
| 6436 | |
| 6437 | return RUs; |
| 6438 | } |
| 6439 | |
| 6440 | bool LoopVectorizationCostModel::useEmulatedMaskMemRefHack(Instruction *I, |
| 6441 | ElementCount VF) { |
| 6442 | // TODO: Cost model for emulated masked load/store is completely |
| 6443 | // broken. This hack guides the cost model to use an artificially |
| 6444 | // high enough value to practically disable vectorization with such |
| 6445 | // operations, except where previously deployed legality hack allowed |
| 6446 | // using very low cost values. This is to avoid regressions coming simply |
| 6447 | // from moving "masked load/store" check from legality to cost model. |
| 6448 | // Masked Load/Gather emulation was previously never allowed. |
| 6449 | // Limited number of Masked Store/Scatter emulation was allowed. |
| 6450 | assert(isPredicatedInst(I, VF) && "Expecting a scalar emulated instruction")(static_cast <bool> (isPredicatedInst(I, VF) && "Expecting a scalar emulated instruction") ? void (0) : __assert_fail ("isPredicatedInst(I, VF) && \"Expecting a scalar emulated instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6450, __extension__ __PRETTY_FUNCTION__)); |
| 6451 | return isa<LoadInst>(I) || |
| 6452 | (isa<StoreInst>(I) && |
| 6453 | NumPredStores > NumberOfStoresToPredicate); |
| 6454 | } |
| 6455 | |
| 6456 | void LoopVectorizationCostModel::collectInstsToScalarize(ElementCount VF) { |
| 6457 | // If we aren't vectorizing the loop, or if we've already collected the |
| 6458 | // instructions to scalarize, there's nothing to do. Collection may already |
| 6459 | // have occurred if we have a user-selected VF and are now computing the |
| 6460 | // expected cost for interleaving. |
| 6461 | if (VF.isScalar() || VF.isZero() || |
| 6462 | InstsToScalarize.find(VF) != InstsToScalarize.end()) |
| 6463 | return; |
| 6464 | |
| 6465 | // Initialize a mapping for VF in InstsToScalalarize. If we find that it's |
| 6466 | // not profitable to scalarize any instructions, the presence of VF in the |
| 6467 | // map will indicate that we've analyzed it already. |
| 6468 | ScalarCostsTy &ScalarCostsVF = InstsToScalarize[VF]; |
| 6469 | |
| 6470 | // Find all the instructions that are scalar with predication in the loop and |
| 6471 | // determine if it would be better to not if-convert the blocks they are in. |
| 6472 | // If so, we also record the instructions to scalarize. |
| 6473 | for (BasicBlock *BB : TheLoop->blocks()) { |
| 6474 | if (!blockNeedsPredicationForAnyReason(BB)) |
| 6475 | continue; |
| 6476 | for (Instruction &I : *BB) |
| 6477 | if (isScalarWithPredication(&I, VF)) { |
| 6478 | ScalarCostsTy ScalarCosts; |
| 6479 | // Do not apply discount if scalable, because that would lead to |
| 6480 | // invalid scalarization costs. |
| 6481 | // Do not apply discount logic if hacked cost is needed |
| 6482 | // for emulated masked memrefs. |
| 6483 | if (!VF.isScalable() && !useEmulatedMaskMemRefHack(&I, VF) && |
| 6484 | computePredInstDiscount(&I, ScalarCosts, VF) >= 0) |
| 6485 | ScalarCostsVF.insert(ScalarCosts.begin(), ScalarCosts.end()); |
| 6486 | // Remember that BB will remain after vectorization. |
| 6487 | PredicatedBBsAfterVectorization.insert(BB); |
| 6488 | } |
| 6489 | } |
| 6490 | } |
| 6491 | |
| 6492 | int LoopVectorizationCostModel::computePredInstDiscount( |
| 6493 | Instruction *PredInst, ScalarCostsTy &ScalarCosts, ElementCount VF) { |
| 6494 | assert(!isUniformAfterVectorization(PredInst, VF) &&(static_cast <bool> (!isUniformAfterVectorization(PredInst , VF) && "Instruction marked uniform-after-vectorization will be predicated" ) ? void (0) : __assert_fail ("!isUniformAfterVectorization(PredInst, VF) && \"Instruction marked uniform-after-vectorization will be predicated\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6495, __extension__ __PRETTY_FUNCTION__)) |
| 6495 | "Instruction marked uniform-after-vectorization will be predicated")(static_cast <bool> (!isUniformAfterVectorization(PredInst , VF) && "Instruction marked uniform-after-vectorization will be predicated" ) ? void (0) : __assert_fail ("!isUniformAfterVectorization(PredInst, VF) && \"Instruction marked uniform-after-vectorization will be predicated\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6495, __extension__ __PRETTY_FUNCTION__)); |
| 6496 | |
| 6497 | // Initialize the discount to zero, meaning that the scalar version and the |
| 6498 | // vector version cost the same. |
| 6499 | InstructionCost Discount = 0; |
| 6500 | |
| 6501 | // Holds instructions to analyze. The instructions we visit are mapped in |
| 6502 | // ScalarCosts. Those instructions are the ones that would be scalarized if |
| 6503 | // we find that the scalar version costs less. |
| 6504 | SmallVector<Instruction *, 8> Worklist; |
| 6505 | |
| 6506 | // Returns true if the given instruction can be scalarized. |
| 6507 | auto canBeScalarized = [&](Instruction *I) -> bool { |
| 6508 | // We only attempt to scalarize instructions forming a single-use chain |
| 6509 | // from the original predicated block that would otherwise be vectorized. |
| 6510 | // Although not strictly necessary, we give up on instructions we know will |
| 6511 | // already be scalar to avoid traversing chains that are unlikely to be |
| 6512 | // beneficial. |
| 6513 | if (!I->hasOneUse() || PredInst->getParent() != I->getParent() || |
| 6514 | isScalarAfterVectorization(I, VF)) |
| 6515 | return false; |
| 6516 | |
| 6517 | // If the instruction is scalar with predication, it will be analyzed |
| 6518 | // separately. We ignore it within the context of PredInst. |
| 6519 | if (isScalarWithPredication(I, VF)) |
| 6520 | return false; |
| 6521 | |
| 6522 | // If any of the instruction's operands are uniform after vectorization, |
| 6523 | // the instruction cannot be scalarized. This prevents, for example, a |
| 6524 | // masked load from being scalarized. |
| 6525 | // |
| 6526 | // We assume we will only emit a value for lane zero of an instruction |
| 6527 | // marked uniform after vectorization, rather than VF identical values. |
| 6528 | // Thus, if we scalarize an instruction that uses a uniform, we would |
| 6529 | // create uses of values corresponding to the lanes we aren't emitting code |
| 6530 | // for. This behavior can be changed by allowing getScalarValue to clone |
| 6531 | // the lane zero values for uniforms rather than asserting. |
| 6532 | for (Use &U : I->operands()) |
| 6533 | if (auto *J = dyn_cast<Instruction>(U.get())) |
| 6534 | if (isUniformAfterVectorization(J, VF)) |
| 6535 | return false; |
| 6536 | |
| 6537 | // Otherwise, we can scalarize the instruction. |
| 6538 | return true; |
| 6539 | }; |
| 6540 | |
| 6541 | // Compute the expected cost discount from scalarizing the entire expression |
| 6542 | // feeding the predicated instruction. We currently only consider expressions |
| 6543 | // that are single-use instruction chains. |
| 6544 | Worklist.push_back(PredInst); |
| 6545 | while (!Worklist.empty()) { |
| 6546 | Instruction *I = Worklist.pop_back_val(); |
| 6547 | |
| 6548 | // If we've already analyzed the instruction, there's nothing to do. |
| 6549 | if (ScalarCosts.find(I) != ScalarCosts.end()) |
| 6550 | continue; |
| 6551 | |
| 6552 | // Compute the cost of the vector instruction. Note that this cost already |
| 6553 | // includes the scalarization overhead of the predicated instruction. |
| 6554 | InstructionCost VectorCost = getInstructionCost(I, VF).first; |
| 6555 | |
| 6556 | // Compute the cost of the scalarized instruction. This cost is the cost of |
| 6557 | // the instruction as if it wasn't if-converted and instead remained in the |
| 6558 | // predicated block. We will scale this cost by block probability after |
| 6559 | // computing the scalarization overhead. |
| 6560 | InstructionCost ScalarCost = |
| 6561 | VF.getFixedValue() * |
| 6562 | getInstructionCost(I, ElementCount::getFixed(1)).first; |
| 6563 | |
| 6564 | // Compute the scalarization overhead of needed insertelement instructions |
| 6565 | // and phi nodes. |
| 6566 | if (isScalarWithPredication(I, VF) && !I->getType()->isVoidTy()) { |
| 6567 | ScalarCost += TTI.getScalarizationOverhead( |
| 6568 | cast<VectorType>(ToVectorTy(I->getType(), VF)), |
| 6569 | APInt::getAllOnes(VF.getFixedValue()), true, false); |
| 6570 | ScalarCost += |
| 6571 | VF.getFixedValue() * |
| 6572 | TTI.getCFInstrCost(Instruction::PHI, TTI::TCK_RecipThroughput); |
| 6573 | } |
| 6574 | |
| 6575 | // Compute the scalarization overhead of needed extractelement |
| 6576 | // instructions. For each of the instruction's operands, if the operand can |
| 6577 | // be scalarized, add it to the worklist; otherwise, account for the |
| 6578 | // overhead. |
| 6579 | for (Use &U : I->operands()) |
| 6580 | if (auto *J = dyn_cast<Instruction>(U.get())) { |
| 6581 | assert(VectorType::isValidElementType(J->getType()) &&(static_cast <bool> (VectorType::isValidElementType(J-> getType()) && "Instruction has non-scalar type") ? void (0) : __assert_fail ("VectorType::isValidElementType(J->getType()) && \"Instruction has non-scalar type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6582, __extension__ __PRETTY_FUNCTION__)) |
| 6582 | "Instruction has non-scalar type")(static_cast <bool> (VectorType::isValidElementType(J-> getType()) && "Instruction has non-scalar type") ? void (0) : __assert_fail ("VectorType::isValidElementType(J->getType()) && \"Instruction has non-scalar type\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6582, __extension__ __PRETTY_FUNCTION__)); |
| 6583 | if (canBeScalarized(J)) |
| 6584 | Worklist.push_back(J); |
| 6585 | else if (needsExtract(J, VF)) { |
| 6586 | ScalarCost += TTI.getScalarizationOverhead( |
| 6587 | cast<VectorType>(ToVectorTy(J->getType(), VF)), |
| 6588 | APInt::getAllOnes(VF.getFixedValue()), false, true); |
| 6589 | } |
| 6590 | } |
| 6591 | |
| 6592 | // Scale the total scalar cost by block probability. |
| 6593 | ScalarCost /= getReciprocalPredBlockProb(); |
| 6594 | |
| 6595 | // Compute the discount. A non-negative discount means the vector version |
| 6596 | // of the instruction costs more, and scalarizing would be beneficial. |
| 6597 | Discount += VectorCost - ScalarCost; |
| 6598 | ScalarCosts[I] = ScalarCost; |
| 6599 | } |
| 6600 | |
| 6601 | return *Discount.getValue(); |
| 6602 | } |
| 6603 | |
| 6604 | LoopVectorizationCostModel::VectorizationCostTy |
| 6605 | LoopVectorizationCostModel::expectedCost( |
| 6606 | ElementCount VF, SmallVectorImpl<InstructionVFPair> *Invalid) { |
| 6607 | VectorizationCostTy Cost; |
| 6608 | |
| 6609 | // For each block. |
| 6610 | for (BasicBlock *BB : TheLoop->blocks()) { |
| 6611 | VectorizationCostTy BlockCost; |
| 6612 | |
| 6613 | // For each instruction in the old loop. |
| 6614 | for (Instruction &I : BB->instructionsWithoutDebug()) { |
| 6615 | // Skip ignored values. |
| 6616 | if (ValuesToIgnore.count(&I) || |
| 6617 | (VF.isVector() && VecValuesToIgnore.count(&I))) |
| 6618 | continue; |
| 6619 | |
| 6620 | VectorizationCostTy C = getInstructionCost(&I, VF); |
| 6621 | |
| 6622 | // Check if we should override the cost. |
| 6623 | if (C.first.isValid() && |
| 6624 | ForceTargetInstructionCost.getNumOccurrences() > 0) |
| 6625 | C.first = InstructionCost(ForceTargetInstructionCost); |
| 6626 | |
| 6627 | // Keep a list of instructions with invalid costs. |
| 6628 | if (Invalid && !C.first.isValid()) |
| 6629 | Invalid->emplace_back(&I, VF); |
| 6630 | |
| 6631 | BlockCost.first += C.first; |
| 6632 | BlockCost.second |= C.second; |
| 6633 | LLVM_DEBUG(dbgs() << "LV: Found an estimated cost of " << C.firstdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found an estimated cost of " << C.first << " for VF " << VF << " For instruction: " << I << '\n'; } } while (false) |
| 6634 | << " for VF " << VF << " For instruction: " << Ido { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found an estimated cost of " << C.first << " for VF " << VF << " For instruction: " << I << '\n'; } } while (false) |
| 6635 | << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found an estimated cost of " << C.first << " for VF " << VF << " For instruction: " << I << '\n'; } } while (false); |
| 6636 | } |
| 6637 | |
| 6638 | // If we are vectorizing a predicated block, it will have been |
| 6639 | // if-converted. This means that the block's instructions (aside from |
| 6640 | // stores and instructions that may divide by zero) will now be |
| 6641 | // unconditionally executed. For the scalar case, we may not always execute |
| 6642 | // the predicated block, if it is an if-else block. Thus, scale the block's |
| 6643 | // cost by the probability of executing it. blockNeedsPredication from |
| 6644 | // Legal is used so as to not include all blocks in tail folded loops. |
| 6645 | if (VF.isScalar() && Legal->blockNeedsPredication(BB)) |
| 6646 | BlockCost.first /= getReciprocalPredBlockProb(); |
| 6647 | |
| 6648 | Cost.first += BlockCost.first; |
| 6649 | Cost.second |= BlockCost.second; |
| 6650 | } |
| 6651 | |
| 6652 | return Cost; |
| 6653 | } |
| 6654 | |
| 6655 | /// Gets Address Access SCEV after verifying that the access pattern |
| 6656 | /// is loop invariant except the induction variable dependence. |
| 6657 | /// |
| 6658 | /// This SCEV can be sent to the Target in order to estimate the address |
| 6659 | /// calculation cost. |
| 6660 | static const SCEV *getAddressAccessSCEV( |
| 6661 | Value *Ptr, |
| 6662 | LoopVectorizationLegality *Legal, |
| 6663 | PredicatedScalarEvolution &PSE, |
| 6664 | const Loop *TheLoop) { |
| 6665 | |
| 6666 | auto *Gep = dyn_cast<GetElementPtrInst>(Ptr); |
| 6667 | if (!Gep) |
| 6668 | return nullptr; |
| 6669 | |
| 6670 | // We are looking for a gep with all loop invariant indices except for one |
| 6671 | // which should be an induction variable. |
| 6672 | auto SE = PSE.getSE(); |
| 6673 | unsigned NumOperands = Gep->getNumOperands(); |
| 6674 | for (unsigned i = 1; i < NumOperands; ++i) { |
| 6675 | Value *Opd = Gep->getOperand(i); |
| 6676 | if (!SE->isLoopInvariant(SE->getSCEV(Opd), TheLoop) && |
| 6677 | !Legal->isInductionVariable(Opd)) |
| 6678 | return nullptr; |
| 6679 | } |
| 6680 | |
| 6681 | // Now we know we have a GEP ptr, %inv, %ind, %inv. return the Ptr SCEV. |
| 6682 | return PSE.getSCEV(Ptr); |
| 6683 | } |
| 6684 | |
| 6685 | static bool isStrideMul(Instruction *I, LoopVectorizationLegality *Legal) { |
| 6686 | return Legal->hasStride(I->getOperand(0)) || |
| 6687 | Legal->hasStride(I->getOperand(1)); |
| 6688 | } |
| 6689 | |
| 6690 | InstructionCost |
| 6691 | LoopVectorizationCostModel::getMemInstScalarizationCost(Instruction *I, |
| 6692 | ElementCount VF) { |
| 6693 | assert(VF.isVector() &&(static_cast <bool> (VF.isVector() && "Scalarization cost of instruction implies vectorization." ) ? void (0) : __assert_fail ("VF.isVector() && \"Scalarization cost of instruction implies vectorization.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6694, __extension__ __PRETTY_FUNCTION__)) |
| 6694 | "Scalarization cost of instruction implies vectorization.")(static_cast <bool> (VF.isVector() && "Scalarization cost of instruction implies vectorization." ) ? void (0) : __assert_fail ("VF.isVector() && \"Scalarization cost of instruction implies vectorization.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6694, __extension__ __PRETTY_FUNCTION__)); |
| 6695 | if (VF.isScalable()) |
| 6696 | return InstructionCost::getInvalid(); |
| 6697 | |
| 6698 | Type *ValTy = getLoadStoreType(I); |
| 6699 | auto SE = PSE.getSE(); |
| 6700 | |
| 6701 | unsigned AS = getLoadStoreAddressSpace(I); |
| 6702 | Value *Ptr = getLoadStorePointerOperand(I); |
| 6703 | Type *PtrTy = ToVectorTy(Ptr->getType(), VF); |
| 6704 | // NOTE: PtrTy is a vector to signal `TTI::getAddressComputationCost` |
| 6705 | // that it is being called from this specific place. |
| 6706 | |
| 6707 | // Figure out whether the access is strided and get the stride value |
| 6708 | // if it's known in compile time |
| 6709 | const SCEV *PtrSCEV = getAddressAccessSCEV(Ptr, Legal, PSE, TheLoop); |
| 6710 | |
| 6711 | // Get the cost of the scalar memory instruction and address computation. |
| 6712 | InstructionCost Cost = |
| 6713 | VF.getKnownMinValue() * TTI.getAddressComputationCost(PtrTy, SE, PtrSCEV); |
| 6714 | |
| 6715 | // Don't pass *I here, since it is scalar but will actually be part of a |
| 6716 | // vectorized loop where the user of it is a vectorized instruction. |
| 6717 | const Align Alignment = getLoadStoreAlignment(I); |
| 6718 | Cost += VF.getKnownMinValue() * |
| 6719 | TTI.getMemoryOpCost(I->getOpcode(), ValTy->getScalarType(), Alignment, |
| 6720 | AS, TTI::TCK_RecipThroughput); |
| 6721 | |
| 6722 | // Get the overhead of the extractelement and insertelement instructions |
| 6723 | // we might create due to scalarization. |
| 6724 | Cost += getScalarizationOverhead(I, VF); |
| 6725 | |
| 6726 | // If we have a predicated load/store, it will need extra i1 extracts and |
| 6727 | // conditional branches, but may not be executed for each vector lane. Scale |
| 6728 | // the cost by the probability of executing the predicated block. |
| 6729 | if (isPredicatedInst(I, VF)) { |
| 6730 | Cost /= getReciprocalPredBlockProb(); |
| 6731 | |
| 6732 | // Add the cost of an i1 extract and a branch |
| 6733 | auto *Vec_i1Ty = |
| 6734 | VectorType::get(IntegerType::getInt1Ty(ValTy->getContext()), VF); |
| 6735 | Cost += TTI.getScalarizationOverhead( |
| 6736 | Vec_i1Ty, APInt::getAllOnes(VF.getKnownMinValue()), |
| 6737 | /*Insert=*/false, /*Extract=*/true); |
| 6738 | Cost += TTI.getCFInstrCost(Instruction::Br, TTI::TCK_RecipThroughput); |
| 6739 | |
| 6740 | if (useEmulatedMaskMemRefHack(I, VF)) |
| 6741 | // Artificially setting to a high enough value to practically disable |
| 6742 | // vectorization with such operations. |
| 6743 | Cost = 3000000; |
| 6744 | } |
| 6745 | |
| 6746 | return Cost; |
| 6747 | } |
| 6748 | |
| 6749 | InstructionCost |
| 6750 | LoopVectorizationCostModel::getConsecutiveMemOpCost(Instruction *I, |
| 6751 | ElementCount VF) { |
| 6752 | Type *ValTy = getLoadStoreType(I); |
| 6753 | auto *VectorTy = cast<VectorType>(ToVectorTy(ValTy, VF)); |
| 6754 | Value *Ptr = getLoadStorePointerOperand(I); |
| 6755 | unsigned AS = getLoadStoreAddressSpace(I); |
| 6756 | int ConsecutiveStride = Legal->isConsecutivePtr(ValTy, Ptr); |
| 6757 | enum TTI::TargetCostKind CostKind = TTI::TCK_RecipThroughput; |
| 6758 | |
| 6759 | assert((ConsecutiveStride == 1 || ConsecutiveStride == -1) &&(static_cast <bool> ((ConsecutiveStride == 1 || ConsecutiveStride == -1) && "Stride should be 1 or -1 for consecutive memory access" ) ? void (0) : __assert_fail ("(ConsecutiveStride == 1 || ConsecutiveStride == -1) && \"Stride should be 1 or -1 for consecutive memory access\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6760, __extension__ __PRETTY_FUNCTION__)) |
| 6760 | "Stride should be 1 or -1 for consecutive memory access")(static_cast <bool> ((ConsecutiveStride == 1 || ConsecutiveStride == -1) && "Stride should be 1 or -1 for consecutive memory access" ) ? void (0) : __assert_fail ("(ConsecutiveStride == 1 || ConsecutiveStride == -1) && \"Stride should be 1 or -1 for consecutive memory access\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6760, __extension__ __PRETTY_FUNCTION__)); |
| 6761 | const Align Alignment = getLoadStoreAlignment(I); |
| 6762 | InstructionCost Cost = 0; |
| 6763 | if (Legal->isMaskRequired(I)) |
| 6764 | Cost += TTI.getMaskedMemoryOpCost(I->getOpcode(), VectorTy, Alignment, AS, |
| 6765 | CostKind); |
| 6766 | else |
| 6767 | Cost += TTI.getMemoryOpCost(I->getOpcode(), VectorTy, Alignment, AS, |
| 6768 | CostKind, I); |
| 6769 | |
| 6770 | bool Reverse = ConsecutiveStride < 0; |
| 6771 | if (Reverse) |
| 6772 | Cost += |
| 6773 | TTI.getShuffleCost(TargetTransformInfo::SK_Reverse, VectorTy, None, 0); |
| 6774 | return Cost; |
| 6775 | } |
| 6776 | |
| 6777 | InstructionCost |
| 6778 | LoopVectorizationCostModel::getUniformMemOpCost(Instruction *I, |
| 6779 | ElementCount VF) { |
| 6780 | assert(Legal->isUniformMemOp(*I))(static_cast <bool> (Legal->isUniformMemOp(*I)) ? void (0) : __assert_fail ("Legal->isUniformMemOp(*I)", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 6780, __extension__ __PRETTY_FUNCTION__)); |
| 6781 | |
| 6782 | Type *ValTy = getLoadStoreType(I); |
| 6783 | auto *VectorTy = cast<VectorType>(ToVectorTy(ValTy, VF)); |
| 6784 | const Align Alignment = getLoadStoreAlignment(I); |
| 6785 | unsigned AS = getLoadStoreAddressSpace(I); |
| 6786 | enum TTI::TargetCostKind CostKind = TTI::TCK_RecipThroughput; |
| 6787 | if (isa<LoadInst>(I)) { |
| 6788 | return TTI.getAddressComputationCost(ValTy) + |
| 6789 | TTI.getMemoryOpCost(Instruction::Load, ValTy, Alignment, AS, |
| 6790 | CostKind) + |
| 6791 | TTI.getShuffleCost(TargetTransformInfo::SK_Broadcast, VectorTy); |
| 6792 | } |
| 6793 | StoreInst *SI = cast<StoreInst>(I); |
| 6794 | |
| 6795 | bool isLoopInvariantStoreValue = Legal->isUniform(SI->getValueOperand()); |
| 6796 | return TTI.getAddressComputationCost(ValTy) + |
| 6797 | TTI.getMemoryOpCost(Instruction::Store, ValTy, Alignment, AS, |
| 6798 | CostKind) + |
| 6799 | (isLoopInvariantStoreValue |
| 6800 | ? 0 |
| 6801 | : TTI.getVectorInstrCost(Instruction::ExtractElement, VectorTy, |
| 6802 | VF.getKnownMinValue() - 1)); |
| 6803 | } |
| 6804 | |
| 6805 | InstructionCost |
| 6806 | LoopVectorizationCostModel::getGatherScatterCost(Instruction *I, |
| 6807 | ElementCount VF) { |
| 6808 | Type *ValTy = getLoadStoreType(I); |
| 6809 | auto *VectorTy = cast<VectorType>(ToVectorTy(ValTy, VF)); |
| 6810 | const Align Alignment = getLoadStoreAlignment(I); |
| 6811 | const Value *Ptr = getLoadStorePointerOperand(I); |
| 6812 | |
| 6813 | return TTI.getAddressComputationCost(VectorTy) + |
| 6814 | TTI.getGatherScatterOpCost( |
| 6815 | I->getOpcode(), VectorTy, Ptr, Legal->isMaskRequired(I), Alignment, |
| 6816 | TargetTransformInfo::TCK_RecipThroughput, I); |
| 6817 | } |
| 6818 | |
| 6819 | InstructionCost |
| 6820 | LoopVectorizationCostModel::getInterleaveGroupCost(Instruction *I, |
| 6821 | ElementCount VF) { |
| 6822 | // TODO: Once we have support for interleaving with scalable vectors |
| 6823 | // we can calculate the cost properly here. |
| 6824 | if (VF.isScalable()) |
| 6825 | return InstructionCost::getInvalid(); |
| 6826 | |
| 6827 | Type *ValTy = getLoadStoreType(I); |
| 6828 | auto *VectorTy = cast<VectorType>(ToVectorTy(ValTy, VF)); |
| 6829 | unsigned AS = getLoadStoreAddressSpace(I); |
| 6830 | |
| 6831 | auto Group = getInterleavedAccessGroup(I); |
| 6832 | assert(Group && "Fail to get an interleaved access group.")(static_cast <bool> (Group && "Fail to get an interleaved access group." ) ? void (0) : __assert_fail ("Group && \"Fail to get an interleaved access group.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6832, __extension__ __PRETTY_FUNCTION__)); |
| 6833 | |
| 6834 | unsigned InterleaveFactor = Group->getFactor(); |
| 6835 | auto *WideVecTy = VectorType::get(ValTy, VF * InterleaveFactor); |
| 6836 | |
| 6837 | // Holds the indices of existing members in the interleaved group. |
| 6838 | SmallVector<unsigned, 4> Indices; |
| 6839 | for (unsigned IF = 0; IF < InterleaveFactor; IF++) |
| 6840 | if (Group->getMember(IF)) |
| 6841 | Indices.push_back(IF); |
| 6842 | |
| 6843 | // Calculate the cost of the whole interleaved group. |
| 6844 | bool UseMaskForGaps = |
| 6845 | (Group->requiresScalarEpilogue() && !isScalarEpilogueAllowed()) || |
| 6846 | (isa<StoreInst>(I) && (Group->getNumMembers() < Group->getFactor())); |
| 6847 | InstructionCost Cost = TTI.getInterleavedMemoryOpCost( |
| 6848 | I->getOpcode(), WideVecTy, Group->getFactor(), Indices, Group->getAlign(), |
| 6849 | AS, TTI::TCK_RecipThroughput, Legal->isMaskRequired(I), UseMaskForGaps); |
| 6850 | |
| 6851 | if (Group->isReverse()) { |
| 6852 | // TODO: Add support for reversed masked interleaved access. |
| 6853 | assert(!Legal->isMaskRequired(I) &&(static_cast <bool> (!Legal->isMaskRequired(I) && "Reverse masked interleaved access not supported.") ? void ( 0) : __assert_fail ("!Legal->isMaskRequired(I) && \"Reverse masked interleaved access not supported.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6854, __extension__ __PRETTY_FUNCTION__)) |
| 6854 | "Reverse masked interleaved access not supported.")(static_cast <bool> (!Legal->isMaskRequired(I) && "Reverse masked interleaved access not supported.") ? void ( 0) : __assert_fail ("!Legal->isMaskRequired(I) && \"Reverse masked interleaved access not supported.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 6854, __extension__ __PRETTY_FUNCTION__)); |
| 6855 | Cost += |
| 6856 | Group->getNumMembers() * |
| 6857 | TTI.getShuffleCost(TargetTransformInfo::SK_Reverse, VectorTy, None, 0); |
| 6858 | } |
| 6859 | return Cost; |
| 6860 | } |
| 6861 | |
| 6862 | Optional<InstructionCost> LoopVectorizationCostModel::getReductionPatternCost( |
| 6863 | Instruction *I, ElementCount VF, Type *Ty, TTI::TargetCostKind CostKind) { |
| 6864 | using namespace llvm::PatternMatch; |
| 6865 | // Early exit for no inloop reductions |
| 6866 | if (InLoopReductionChains.empty() || VF.isScalar() || !isa<VectorType>(Ty)) |
| 6867 | return None; |
| 6868 | auto *VectorTy = cast<VectorType>(Ty); |
| 6869 | |
| 6870 | // We are looking for a pattern of, and finding the minimal acceptable cost: |
| 6871 | // reduce(mul(ext(A), ext(B))) or |
| 6872 | // reduce(mul(A, B)) or |
| 6873 | // reduce(ext(A)) or |
| 6874 | // reduce(A). |
| 6875 | // The basic idea is that we walk down the tree to do that, finding the root |
| 6876 | // reduction instruction in InLoopReductionImmediateChains. From there we find |
| 6877 | // the pattern of mul/ext and test the cost of the entire pattern vs the cost |
| 6878 | // of the components. If the reduction cost is lower then we return it for the |
| 6879 | // reduction instruction and 0 for the other instructions in the pattern. If |
| 6880 | // it is not we return an invalid cost specifying the orignal cost method |
| 6881 | // should be used. |
| 6882 | Instruction *RetI = I; |
| 6883 | if (match(RetI, m_ZExtOrSExt(m_Value()))) { |
| 6884 | if (!RetI->hasOneUser()) |
| 6885 | return None; |
| 6886 | RetI = RetI->user_back(); |
| 6887 | } |
| 6888 | if (match(RetI, m_Mul(m_Value(), m_Value())) && |
| 6889 | RetI->user_back()->getOpcode() == Instruction::Add) { |
| 6890 | if (!RetI->hasOneUser()) |
| 6891 | return None; |
| 6892 | RetI = RetI->user_back(); |
| 6893 | } |
| 6894 | |
| 6895 | // Test if the found instruction is a reduction, and if not return an invalid |
| 6896 | // cost specifying the parent to use the original cost modelling. |
| 6897 | if (!InLoopReductionImmediateChains.count(RetI)) |
| 6898 | return None; |
| 6899 | |
| 6900 | // Find the reduction this chain is a part of and calculate the basic cost of |
| 6901 | // the reduction on its own. |
| 6902 | Instruction *LastChain = InLoopReductionImmediateChains[RetI]; |
| 6903 | Instruction *ReductionPhi = LastChain; |
| 6904 | while (!isa<PHINode>(ReductionPhi)) |
| 6905 | ReductionPhi = InLoopReductionImmediateChains[ReductionPhi]; |
| 6906 | |
| 6907 | const RecurrenceDescriptor &RdxDesc = |
| 6908 | Legal->getReductionVars().find(cast<PHINode>(ReductionPhi))->second; |
| 6909 | |
| 6910 | InstructionCost BaseCost = TTI.getArithmeticReductionCost( |
| 6911 | RdxDesc.getOpcode(), VectorTy, RdxDesc.getFastMathFlags(), CostKind); |
| 6912 | |
| 6913 | // For a call to the llvm.fmuladd intrinsic we need to add the cost of a |
| 6914 | // normal fmul instruction to the cost of the fadd reduction. |
| 6915 | if (RdxDesc.getRecurrenceKind() == RecurKind::FMulAdd) |
| 6916 | BaseCost += |
| 6917 | TTI.getArithmeticInstrCost(Instruction::FMul, VectorTy, CostKind); |
| 6918 | |
| 6919 | // If we're using ordered reductions then we can just return the base cost |
| 6920 | // here, since getArithmeticReductionCost calculates the full ordered |
| 6921 | // reduction cost when FP reassociation is not allowed. |
| 6922 | if (useOrderedReductions(RdxDesc)) |
| 6923 | return BaseCost; |
| 6924 | |
| 6925 | // Get the operand that was not the reduction chain and match it to one of the |
| 6926 | // patterns, returning the better cost if it is found. |
| 6927 | Instruction *RedOp = RetI->getOperand(1) == LastChain |
| 6928 | ? dyn_cast<Instruction>(RetI->getOperand(0)) |
| 6929 | : dyn_cast<Instruction>(RetI->getOperand(1)); |
| 6930 | |
| 6931 | VectorTy = VectorType::get(I->getOperand(0)->getType(), VectorTy); |
| 6932 | |
| 6933 | Instruction *Op0, *Op1; |
| 6934 | if (RedOp && |
| 6935 | match(RedOp, |
| 6936 | m_ZExtOrSExt(m_Mul(m_Instruction(Op0), m_Instruction(Op1)))) && |
| 6937 | match(Op0, m_ZExtOrSExt(m_Value())) && |
| 6938 | Op0->getOpcode() == Op1->getOpcode() && |
| 6939 | Op0->getOperand(0)->getType() == Op1->getOperand(0)->getType() && |
| 6940 | !TheLoop->isLoopInvariant(Op0) && !TheLoop->isLoopInvariant(Op1) && |
| 6941 | (Op0->getOpcode() == RedOp->getOpcode() || Op0 == Op1)) { |
| 6942 | |
| 6943 | // Matched reduce(ext(mul(ext(A), ext(B))) |
| 6944 | // Note that the extend opcodes need to all match, or if A==B they will have |
| 6945 | // been converted to zext(mul(sext(A), sext(A))) as it is known positive, |
| 6946 | // which is equally fine. |
| 6947 | bool IsUnsigned = isa<ZExtInst>(Op0); |
| 6948 | auto *ExtType = VectorType::get(Op0->getOperand(0)->getType(), VectorTy); |
| 6949 | auto *MulType = VectorType::get(Op0->getType(), VectorTy); |
| 6950 | |
| 6951 | InstructionCost ExtCost = |
| 6952 | TTI.getCastInstrCost(Op0->getOpcode(), MulType, ExtType, |
| 6953 | TTI::CastContextHint::None, CostKind, Op0); |
| 6954 | InstructionCost MulCost = |
| 6955 | TTI.getArithmeticInstrCost(Instruction::Mul, MulType, CostKind); |
| 6956 | InstructionCost Ext2Cost = |
| 6957 | TTI.getCastInstrCost(RedOp->getOpcode(), VectorTy, MulType, |
| 6958 | TTI::CastContextHint::None, CostKind, RedOp); |
| 6959 | |
| 6960 | InstructionCost RedCost = TTI.getExtendedAddReductionCost( |
| 6961 | /*IsMLA=*/true, IsUnsigned, RdxDesc.getRecurrenceType(), ExtType, |
| 6962 | CostKind); |
| 6963 | |
| 6964 | if (RedCost.isValid() && |
| 6965 | RedCost < ExtCost * 2 + MulCost + Ext2Cost + BaseCost) |
| 6966 | return I == RetI ? RedCost : 0; |
| 6967 | } else if (RedOp && match(RedOp, m_ZExtOrSExt(m_Value())) && |
| 6968 | !TheLoop->isLoopInvariant(RedOp)) { |
| 6969 | // Matched reduce(ext(A)) |
| 6970 | bool IsUnsigned = isa<ZExtInst>(RedOp); |
| 6971 | auto *ExtType = VectorType::get(RedOp->getOperand(0)->getType(), VectorTy); |
| 6972 | InstructionCost RedCost = TTI.getExtendedAddReductionCost( |
| 6973 | /*IsMLA=*/false, IsUnsigned, RdxDesc.getRecurrenceType(), ExtType, |
| 6974 | CostKind); |
| 6975 | |
| 6976 | InstructionCost ExtCost = |
| 6977 | TTI.getCastInstrCost(RedOp->getOpcode(), VectorTy, ExtType, |
| 6978 | TTI::CastContextHint::None, CostKind, RedOp); |
| 6979 | if (RedCost.isValid() && RedCost < BaseCost + ExtCost) |
| 6980 | return I == RetI ? RedCost : 0; |
| 6981 | } else if (RedOp && |
| 6982 | match(RedOp, m_Mul(m_Instruction(Op0), m_Instruction(Op1)))) { |
| 6983 | if (match(Op0, m_ZExtOrSExt(m_Value())) && |
| 6984 | Op0->getOpcode() == Op1->getOpcode() && |
| 6985 | !TheLoop->isLoopInvariant(Op0) && !TheLoop->isLoopInvariant(Op1)) { |
| 6986 | bool IsUnsigned = isa<ZExtInst>(Op0); |
| 6987 | Type *Op0Ty = Op0->getOperand(0)->getType(); |
| 6988 | Type *Op1Ty = Op1->getOperand(0)->getType(); |
| 6989 | Type *LargestOpTy = |
| 6990 | Op0Ty->getIntegerBitWidth() < Op1Ty->getIntegerBitWidth() ? Op1Ty |
| 6991 | : Op0Ty; |
| 6992 | auto *ExtType = VectorType::get(LargestOpTy, VectorTy); |
| 6993 | |
| 6994 | // Matched reduce(mul(ext(A), ext(B))), where the two ext may be of |
| 6995 | // different sizes. We take the largest type as the ext to reduce, and add |
| 6996 | // the remaining cost as, for example reduce(mul(ext(ext(A)), ext(B))). |
| 6997 | InstructionCost ExtCost0 = TTI.getCastInstrCost( |
| 6998 | Op0->getOpcode(), VectorTy, VectorType::get(Op0Ty, VectorTy), |
| 6999 | TTI::CastContextHint::None, CostKind, Op0); |
| 7000 | InstructionCost ExtCost1 = TTI.getCastInstrCost( |
| 7001 | Op1->getOpcode(), VectorTy, VectorType::get(Op1Ty, VectorTy), |
| 7002 | TTI::CastContextHint::None, CostKind, Op1); |
| 7003 | InstructionCost MulCost = |
| 7004 | TTI.getArithmeticInstrCost(Instruction::Mul, VectorTy, CostKind); |
| 7005 | |
| 7006 | InstructionCost RedCost = TTI.getExtendedAddReductionCost( |
| 7007 | /*IsMLA=*/true, IsUnsigned, RdxDesc.getRecurrenceType(), ExtType, |
| 7008 | CostKind); |
| 7009 | InstructionCost ExtraExtCost = 0; |
| 7010 | if (Op0Ty != LargestOpTy || Op1Ty != LargestOpTy) { |
| 7011 | Instruction *ExtraExtOp = (Op0Ty != LargestOpTy) ? Op0 : Op1; |
| 7012 | ExtraExtCost = TTI.getCastInstrCost( |
| 7013 | ExtraExtOp->getOpcode(), ExtType, |
| 7014 | VectorType::get(ExtraExtOp->getOperand(0)->getType(), VectorTy), |
| 7015 | TTI::CastContextHint::None, CostKind, ExtraExtOp); |
| 7016 | } |
| 7017 | |
| 7018 | if (RedCost.isValid() && |
| 7019 | (RedCost + ExtraExtCost) < (ExtCost0 + ExtCost1 + MulCost + BaseCost)) |
| 7020 | return I == RetI ? RedCost : 0; |
| 7021 | } else if (!match(I, m_ZExtOrSExt(m_Value()))) { |
| 7022 | // Matched reduce(mul()) |
| 7023 | InstructionCost MulCost = |
| 7024 | TTI.getArithmeticInstrCost(Instruction::Mul, VectorTy, CostKind); |
| 7025 | |
| 7026 | InstructionCost RedCost = TTI.getExtendedAddReductionCost( |
| 7027 | /*IsMLA=*/true, true, RdxDesc.getRecurrenceType(), VectorTy, |
| 7028 | CostKind); |
| 7029 | |
| 7030 | if (RedCost.isValid() && RedCost < MulCost + BaseCost) |
| 7031 | return I == RetI ? RedCost : 0; |
| 7032 | } |
| 7033 | } |
| 7034 | |
| 7035 | return I == RetI ? Optional<InstructionCost>(BaseCost) : None; |
| 7036 | } |
| 7037 | |
| 7038 | InstructionCost |
| 7039 | LoopVectorizationCostModel::getMemoryInstructionCost(Instruction *I, |
| 7040 | ElementCount VF) { |
| 7041 | // Calculate scalar cost only. Vectorization cost should be ready at this |
| 7042 | // moment. |
| 7043 | if (VF.isScalar()) { |
| 7044 | Type *ValTy = getLoadStoreType(I); |
| 7045 | const Align Alignment = getLoadStoreAlignment(I); |
| 7046 | unsigned AS = getLoadStoreAddressSpace(I); |
| 7047 | |
| 7048 | return TTI.getAddressComputationCost(ValTy) + |
| 7049 | TTI.getMemoryOpCost(I->getOpcode(), ValTy, Alignment, AS, |
| 7050 | TTI::TCK_RecipThroughput, I); |
| 7051 | } |
| 7052 | return getWideningCost(I, VF); |
| 7053 | } |
| 7054 | |
| 7055 | LoopVectorizationCostModel::VectorizationCostTy |
| 7056 | LoopVectorizationCostModel::getInstructionCost(Instruction *I, |
| 7057 | ElementCount VF) { |
| 7058 | // If we know that this instruction will remain uniform, check the cost of |
| 7059 | // the scalar version. |
| 7060 | if (isUniformAfterVectorization(I, VF)) |
| 7061 | VF = ElementCount::getFixed(1); |
| 7062 | |
| 7063 | if (VF.isVector() && isProfitableToScalarize(I, VF)) |
| 7064 | return VectorizationCostTy(InstsToScalarize[VF][I], false); |
| 7065 | |
| 7066 | // Forced scalars do not have any scalarization overhead. |
| 7067 | auto ForcedScalar = ForcedScalars.find(VF); |
| 7068 | if (VF.isVector() && ForcedScalar != ForcedScalars.end()) { |
| 7069 | auto InstSet = ForcedScalar->second; |
| 7070 | if (InstSet.count(I)) |
| 7071 | return VectorizationCostTy( |
| 7072 | (getInstructionCost(I, ElementCount::getFixed(1)).first * |
| 7073 | VF.getKnownMinValue()), |
| 7074 | false); |
| 7075 | } |
| 7076 | |
| 7077 | Type *VectorTy; |
| 7078 | InstructionCost C = getInstructionCost(I, VF, VectorTy); |
| 7079 | |
| 7080 | bool TypeNotScalarized = false; |
| 7081 | if (VF.isVector() && VectorTy->isVectorTy()) { |
| 7082 | unsigned NumParts = TTI.getNumberOfParts(VectorTy); |
| 7083 | if (NumParts) |
| 7084 | TypeNotScalarized = NumParts < VF.getKnownMinValue(); |
| 7085 | else |
| 7086 | C = InstructionCost::getInvalid(); |
| 7087 | } |
| 7088 | return VectorizationCostTy(C, TypeNotScalarized); |
| 7089 | } |
| 7090 | |
| 7091 | InstructionCost |
| 7092 | LoopVectorizationCostModel::getScalarizationOverhead(Instruction *I, |
| 7093 | ElementCount VF) const { |
| 7094 | |
| 7095 | // There is no mechanism yet to create a scalable scalarization loop, |
| 7096 | // so this is currently Invalid. |
| 7097 | if (VF.isScalable()) |
| 7098 | return InstructionCost::getInvalid(); |
| 7099 | |
| 7100 | if (VF.isScalar()) |
| 7101 | return 0; |
| 7102 | |
| 7103 | InstructionCost Cost = 0; |
| 7104 | Type *RetTy = ToVectorTy(I->getType(), VF); |
| 7105 | if (!RetTy->isVoidTy() && |
| 7106 | (!isa<LoadInst>(I) || !TTI.supportsEfficientVectorElementLoadStore())) |
| 7107 | Cost += TTI.getScalarizationOverhead( |
| 7108 | cast<VectorType>(RetTy), APInt::getAllOnes(VF.getKnownMinValue()), true, |
| 7109 | false); |
| 7110 | |
| 7111 | // Some targets keep addresses scalar. |
| 7112 | if (isa<LoadInst>(I) && !TTI.prefersVectorizedAddressing()) |
| 7113 | return Cost; |
| 7114 | |
| 7115 | // Some targets support efficient element stores. |
| 7116 | if (isa<StoreInst>(I) && TTI.supportsEfficientVectorElementLoadStore()) |
| 7117 | return Cost; |
| 7118 | |
| 7119 | // Collect operands to consider. |
| 7120 | CallInst *CI = dyn_cast<CallInst>(I); |
| 7121 | Instruction::op_range Ops = CI ? CI->args() : I->operands(); |
| 7122 | |
| 7123 | // Skip operands that do not require extraction/scalarization and do not incur |
| 7124 | // any overhead. |
| 7125 | SmallVector<Type *> Tys; |
| 7126 | for (auto *V : filterExtractingOperands(Ops, VF)) |
| 7127 | Tys.push_back(MaybeVectorizeType(V->getType(), VF)); |
| 7128 | return Cost + TTI.getOperandsScalarizationOverhead( |
| 7129 | filterExtractingOperands(Ops, VF), Tys); |
| 7130 | } |
| 7131 | |
| 7132 | void LoopVectorizationCostModel::setCostBasedWideningDecision(ElementCount VF) { |
| 7133 | if (VF.isScalar()) |
| 7134 | return; |
| 7135 | NumPredStores = 0; |
| 7136 | for (BasicBlock *BB : TheLoop->blocks()) { |
| 7137 | // For each instruction in the old loop. |
| 7138 | for (Instruction &I : *BB) { |
| 7139 | Value *Ptr = getLoadStorePointerOperand(&I); |
| 7140 | if (!Ptr) |
| 7141 | continue; |
| 7142 | |
| 7143 | // TODO: We should generate better code and update the cost model for |
| 7144 | // predicated uniform stores. Today they are treated as any other |
| 7145 | // predicated store (see added test cases in |
| 7146 | // invariant-store-vectorization.ll). |
| 7147 | if (isa<StoreInst>(&I) && isScalarWithPredication(&I, VF)) |
| 7148 | NumPredStores++; |
| 7149 | |
| 7150 | if (Legal->isUniformMemOp(I)) { |
| 7151 | // TODO: Avoid replicating loads and stores instead of |
| 7152 | // relying on instcombine to remove them. |
| 7153 | // Load: Scalar load + broadcast |
| 7154 | // Store: Scalar store + isLoopInvariantStoreValue ? 0 : extract |
| 7155 | InstructionCost Cost; |
| 7156 | if (isa<StoreInst>(&I) && VF.isScalable() && |
| 7157 | isLegalGatherOrScatter(&I, VF)) { |
| 7158 | Cost = getGatherScatterCost(&I, VF); |
| 7159 | setWideningDecision(&I, VF, CM_GatherScatter, Cost); |
| 7160 | } else { |
| 7161 | assert((isa<LoadInst>(&I) || !VF.isScalable()) &&(static_cast <bool> ((isa<LoadInst>(&I) || !VF .isScalable()) && "Cannot yet scalarize uniform stores" ) ? void (0) : __assert_fail ("(isa<LoadInst>(&I) || !VF.isScalable()) && \"Cannot yet scalarize uniform stores\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7162, __extension__ __PRETTY_FUNCTION__)) |
| 7162 | "Cannot yet scalarize uniform stores")(static_cast <bool> ((isa<LoadInst>(&I) || !VF .isScalable()) && "Cannot yet scalarize uniform stores" ) ? void (0) : __assert_fail ("(isa<LoadInst>(&I) || !VF.isScalable()) && \"Cannot yet scalarize uniform stores\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7162, __extension__ __PRETTY_FUNCTION__)); |
| 7163 | Cost = getUniformMemOpCost(&I, VF); |
| 7164 | setWideningDecision(&I, VF, CM_Scalarize, Cost); |
| 7165 | } |
| 7166 | continue; |
| 7167 | } |
| 7168 | |
| 7169 | // We assume that widening is the best solution when possible. |
| 7170 | if (memoryInstructionCanBeWidened(&I, VF)) { |
| 7171 | InstructionCost Cost = getConsecutiveMemOpCost(&I, VF); |
| 7172 | int ConsecutiveStride = Legal->isConsecutivePtr( |
| 7173 | getLoadStoreType(&I), getLoadStorePointerOperand(&I)); |
| 7174 | assert((ConsecutiveStride == 1 || ConsecutiveStride == -1) &&(static_cast <bool> ((ConsecutiveStride == 1 || ConsecutiveStride == -1) && "Expected consecutive stride.") ? void (0) : __assert_fail ("(ConsecutiveStride == 1 || ConsecutiveStride == -1) && \"Expected consecutive stride.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7175, __extension__ __PRETTY_FUNCTION__)) |
| 7175 | "Expected consecutive stride.")(static_cast <bool> ((ConsecutiveStride == 1 || ConsecutiveStride == -1) && "Expected consecutive stride.") ? void (0) : __assert_fail ("(ConsecutiveStride == 1 || ConsecutiveStride == -1) && \"Expected consecutive stride.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7175, __extension__ __PRETTY_FUNCTION__)); |
| 7176 | InstWidening Decision = |
| 7177 | ConsecutiveStride == 1 ? CM_Widen : CM_Widen_Reverse; |
| 7178 | setWideningDecision(&I, VF, Decision, Cost); |
| 7179 | continue; |
| 7180 | } |
| 7181 | |
| 7182 | // Choose between Interleaving, Gather/Scatter or Scalarization. |
| 7183 | InstructionCost InterleaveCost = InstructionCost::getInvalid(); |
| 7184 | unsigned NumAccesses = 1; |
| 7185 | if (isAccessInterleaved(&I)) { |
| 7186 | auto Group = getInterleavedAccessGroup(&I); |
| 7187 | assert(Group && "Fail to get an interleaved access group.")(static_cast <bool> (Group && "Fail to get an interleaved access group." ) ? void (0) : __assert_fail ("Group && \"Fail to get an interleaved access group.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7187, __extension__ __PRETTY_FUNCTION__)); |
| 7188 | |
| 7189 | // Make one decision for the whole group. |
| 7190 | if (getWideningDecision(&I, VF) != CM_Unknown) |
| 7191 | continue; |
| 7192 | |
| 7193 | NumAccesses = Group->getNumMembers(); |
| 7194 | if (interleavedAccessCanBeWidened(&I, VF)) |
| 7195 | InterleaveCost = getInterleaveGroupCost(&I, VF); |
| 7196 | } |
| 7197 | |
| 7198 | InstructionCost GatherScatterCost = |
| 7199 | isLegalGatherOrScatter(&I, VF) |
| 7200 | ? getGatherScatterCost(&I, VF) * NumAccesses |
| 7201 | : InstructionCost::getInvalid(); |
| 7202 | |
| 7203 | InstructionCost ScalarizationCost = |
| 7204 | getMemInstScalarizationCost(&I, VF) * NumAccesses; |
| 7205 | |
| 7206 | // Choose better solution for the current VF, |
| 7207 | // write down this decision and use it during vectorization. |
| 7208 | InstructionCost Cost; |
| 7209 | InstWidening Decision; |
| 7210 | if (InterleaveCost <= GatherScatterCost && |
| 7211 | InterleaveCost < ScalarizationCost) { |
| 7212 | Decision = CM_Interleave; |
| 7213 | Cost = InterleaveCost; |
| 7214 | } else if (GatherScatterCost < ScalarizationCost) { |
| 7215 | Decision = CM_GatherScatter; |
| 7216 | Cost = GatherScatterCost; |
| 7217 | } else { |
| 7218 | Decision = CM_Scalarize; |
| 7219 | Cost = ScalarizationCost; |
| 7220 | } |
| 7221 | // If the instructions belongs to an interleave group, the whole group |
| 7222 | // receives the same decision. The whole group receives the cost, but |
| 7223 | // the cost will actually be assigned to one instruction. |
| 7224 | if (auto Group = getInterleavedAccessGroup(&I)) |
| 7225 | setWideningDecision(Group, VF, Decision, Cost); |
| 7226 | else |
| 7227 | setWideningDecision(&I, VF, Decision, Cost); |
| 7228 | } |
| 7229 | } |
| 7230 | |
| 7231 | // Make sure that any load of address and any other address computation |
| 7232 | // remains scalar unless there is gather/scatter support. This avoids |
| 7233 | // inevitable extracts into address registers, and also has the benefit of |
| 7234 | // activating LSR more, since that pass can't optimize vectorized |
| 7235 | // addresses. |
| 7236 | if (TTI.prefersVectorizedAddressing()) |
| 7237 | return; |
| 7238 | |
| 7239 | // Start with all scalar pointer uses. |
| 7240 | SmallPtrSet<Instruction *, 8> AddrDefs; |
| 7241 | for (BasicBlock *BB : TheLoop->blocks()) |
| 7242 | for (Instruction &I : *BB) { |
| 7243 | Instruction *PtrDef = |
| 7244 | dyn_cast_or_null<Instruction>(getLoadStorePointerOperand(&I)); |
| 7245 | if (PtrDef && TheLoop->contains(PtrDef) && |
| 7246 | getWideningDecision(&I, VF) != CM_GatherScatter) |
| 7247 | AddrDefs.insert(PtrDef); |
| 7248 | } |
| 7249 | |
| 7250 | // Add all instructions used to generate the addresses. |
| 7251 | SmallVector<Instruction *, 4> Worklist; |
| 7252 | append_range(Worklist, AddrDefs); |
| 7253 | while (!Worklist.empty()) { |
| 7254 | Instruction *I = Worklist.pop_back_val(); |
| 7255 | for (auto &Op : I->operands()) |
| 7256 | if (auto *InstOp = dyn_cast<Instruction>(Op)) |
| 7257 | if ((InstOp->getParent() == I->getParent()) && !isa<PHINode>(InstOp) && |
| 7258 | AddrDefs.insert(InstOp).second) |
| 7259 | Worklist.push_back(InstOp); |
| 7260 | } |
| 7261 | |
| 7262 | for (auto *I : AddrDefs) { |
| 7263 | if (isa<LoadInst>(I)) { |
| 7264 | // Setting the desired widening decision should ideally be handled in |
| 7265 | // by cost functions, but since this involves the task of finding out |
| 7266 | // if the loaded register is involved in an address computation, it is |
| 7267 | // instead changed here when we know this is the case. |
| 7268 | InstWidening Decision = getWideningDecision(I, VF); |
| 7269 | if (Decision == CM_Widen || Decision == CM_Widen_Reverse) |
| 7270 | // Scalarize a widened load of address. |
| 7271 | setWideningDecision( |
| 7272 | I, VF, CM_Scalarize, |
| 7273 | (VF.getKnownMinValue() * |
| 7274 | getMemoryInstructionCost(I, ElementCount::getFixed(1)))); |
| 7275 | else if (auto Group = getInterleavedAccessGroup(I)) { |
| 7276 | // Scalarize an interleave group of address loads. |
| 7277 | for (unsigned I = 0; I < Group->getFactor(); ++I) { |
| 7278 | if (Instruction *Member = Group->getMember(I)) |
| 7279 | setWideningDecision( |
| 7280 | Member, VF, CM_Scalarize, |
| 7281 | (VF.getKnownMinValue() * |
| 7282 | getMemoryInstructionCost(Member, ElementCount::getFixed(1)))); |
| 7283 | } |
| 7284 | } |
| 7285 | } else |
| 7286 | // Make sure I gets scalarized and a cost estimate without |
| 7287 | // scalarization overhead. |
| 7288 | ForcedScalars[VF].insert(I); |
| 7289 | } |
| 7290 | } |
| 7291 | |
| 7292 | InstructionCost |
| 7293 | LoopVectorizationCostModel::getInstructionCost(Instruction *I, ElementCount VF, |
| 7294 | Type *&VectorTy) { |
| 7295 | Type *RetTy = I->getType(); |
| 7296 | if (canTruncateToMinimalBitwidth(I, VF)) |
| 7297 | RetTy = IntegerType::get(RetTy->getContext(), MinBWs[I]); |
| 7298 | auto SE = PSE.getSE(); |
| 7299 | TTI::TargetCostKind CostKind = TTI::TCK_RecipThroughput; |
| 7300 | |
| 7301 | auto hasSingleCopyAfterVectorization = [this](Instruction *I, |
| 7302 | ElementCount VF) -> bool { |
| 7303 | if (VF.isScalar()) |
| 7304 | return true; |
| 7305 | |
| 7306 | auto Scalarized = InstsToScalarize.find(VF); |
| 7307 | assert(Scalarized != InstsToScalarize.end() &&(static_cast <bool> (Scalarized != InstsToScalarize.end () && "VF not yet analyzed for scalarization profitability" ) ? void (0) : __assert_fail ("Scalarized != InstsToScalarize.end() && \"VF not yet analyzed for scalarization profitability\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7308, __extension__ __PRETTY_FUNCTION__)) |
| 7308 | "VF not yet analyzed for scalarization profitability")(static_cast <bool> (Scalarized != InstsToScalarize.end () && "VF not yet analyzed for scalarization profitability" ) ? void (0) : __assert_fail ("Scalarized != InstsToScalarize.end() && \"VF not yet analyzed for scalarization profitability\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7308, __extension__ __PRETTY_FUNCTION__)); |
| 7309 | return !Scalarized->second.count(I) && |
| 7310 | llvm::all_of(I->users(), [&](User *U) { |
| 7311 | auto *UI = cast<Instruction>(U); |
| 7312 | return !Scalarized->second.count(UI); |
| 7313 | }); |
| 7314 | }; |
| 7315 | (void) hasSingleCopyAfterVectorization; |
| 7316 | |
| 7317 | if (isScalarAfterVectorization(I, VF)) { |
| 7318 | // With the exception of GEPs and PHIs, after scalarization there should |
| 7319 | // only be one copy of the instruction generated in the loop. This is |
| 7320 | // because the VF is either 1, or any instructions that need scalarizing |
| 7321 | // have already been dealt with by the the time we get here. As a result, |
| 7322 | // it means we don't have to multiply the instruction cost by VF. |
| 7323 | assert(I->getOpcode() == Instruction::GetElementPtr ||(static_cast <bool> (I->getOpcode() == Instruction:: GetElementPtr || I->getOpcode() == Instruction::PHI || (I-> getOpcode() == Instruction::BitCast && I->getType( )->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF )) ? void (0) : __assert_fail ("I->getOpcode() == Instruction::GetElementPtr || I->getOpcode() == Instruction::PHI || (I->getOpcode() == Instruction::BitCast && I->getType()->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF)" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7327, __extension__ __PRETTY_FUNCTION__)) |
| 7324 | I->getOpcode() == Instruction::PHI ||(static_cast <bool> (I->getOpcode() == Instruction:: GetElementPtr || I->getOpcode() == Instruction::PHI || (I-> getOpcode() == Instruction::BitCast && I->getType( )->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF )) ? void (0) : __assert_fail ("I->getOpcode() == Instruction::GetElementPtr || I->getOpcode() == Instruction::PHI || (I->getOpcode() == Instruction::BitCast && I->getType()->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF)" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7327, __extension__ __PRETTY_FUNCTION__)) |
| 7325 | (I->getOpcode() == Instruction::BitCast &&(static_cast <bool> (I->getOpcode() == Instruction:: GetElementPtr || I->getOpcode() == Instruction::PHI || (I-> getOpcode() == Instruction::BitCast && I->getType( )->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF )) ? void (0) : __assert_fail ("I->getOpcode() == Instruction::GetElementPtr || I->getOpcode() == Instruction::PHI || (I->getOpcode() == Instruction::BitCast && I->getType()->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF)" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7327, __extension__ __PRETTY_FUNCTION__)) |
| 7326 | I->getType()->isPointerTy()) ||(static_cast <bool> (I->getOpcode() == Instruction:: GetElementPtr || I->getOpcode() == Instruction::PHI || (I-> getOpcode() == Instruction::BitCast && I->getType( )->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF )) ? void (0) : __assert_fail ("I->getOpcode() == Instruction::GetElementPtr || I->getOpcode() == Instruction::PHI || (I->getOpcode() == Instruction::BitCast && I->getType()->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF)" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7327, __extension__ __PRETTY_FUNCTION__)) |
| 7327 | hasSingleCopyAfterVectorization(I, VF))(static_cast <bool> (I->getOpcode() == Instruction:: GetElementPtr || I->getOpcode() == Instruction::PHI || (I-> getOpcode() == Instruction::BitCast && I->getType( )->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF )) ? void (0) : __assert_fail ("I->getOpcode() == Instruction::GetElementPtr || I->getOpcode() == Instruction::PHI || (I->getOpcode() == Instruction::BitCast && I->getType()->isPointerTy()) || hasSingleCopyAfterVectorization(I, VF)" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7327, __extension__ __PRETTY_FUNCTION__)); |
| 7328 | VectorTy = RetTy; |
| 7329 | } else |
| 7330 | VectorTy = ToVectorTy(RetTy, VF); |
| 7331 | |
| 7332 | // TODO: We need to estimate the cost of intrinsic calls. |
| 7333 | switch (I->getOpcode()) { |
| 7334 | case Instruction::GetElementPtr: |
| 7335 | // We mark this instruction as zero-cost because the cost of GEPs in |
| 7336 | // vectorized code depends on whether the corresponding memory instruction |
| 7337 | // is scalarized or not. Therefore, we handle GEPs with the memory |
| 7338 | // instruction cost. |
| 7339 | return 0; |
| 7340 | case Instruction::Br: { |
| 7341 | // In cases of scalarized and predicated instructions, there will be VF |
| 7342 | // predicated blocks in the vectorized loop. Each branch around these |
| 7343 | // blocks requires also an extract of its vector compare i1 element. |
| 7344 | bool ScalarPredicatedBB = false; |
| 7345 | BranchInst *BI = cast<BranchInst>(I); |
| 7346 | if (VF.isVector() && BI->isConditional() && |
| 7347 | (PredicatedBBsAfterVectorization.count(BI->getSuccessor(0)) || |
| 7348 | PredicatedBBsAfterVectorization.count(BI->getSuccessor(1)))) |
| 7349 | ScalarPredicatedBB = true; |
| 7350 | |
| 7351 | if (ScalarPredicatedBB) { |
| 7352 | // Not possible to scalarize scalable vector with predicated instructions. |
| 7353 | if (VF.isScalable()) |
| 7354 | return InstructionCost::getInvalid(); |
| 7355 | // Return cost for branches around scalarized and predicated blocks. |
| 7356 | auto *Vec_i1Ty = |
| 7357 | VectorType::get(IntegerType::getInt1Ty(RetTy->getContext()), VF); |
| 7358 | return ( |
| 7359 | TTI.getScalarizationOverhead( |
| 7360 | Vec_i1Ty, APInt::getAllOnes(VF.getFixedValue()), false, true) + |
| 7361 | (TTI.getCFInstrCost(Instruction::Br, CostKind) * VF.getFixedValue())); |
| 7362 | } else if (I->getParent() == TheLoop->getLoopLatch() || VF.isScalar()) |
| 7363 | // The back-edge branch will remain, as will all scalar branches. |
| 7364 | return TTI.getCFInstrCost(Instruction::Br, CostKind); |
| 7365 | else |
| 7366 | // This branch will be eliminated by if-conversion. |
| 7367 | return 0; |
| 7368 | // Note: We currently assume zero cost for an unconditional branch inside |
| 7369 | // a predicated block since it will become a fall-through, although we |
| 7370 | // may decide in the future to call TTI for all branches. |
| 7371 | } |
| 7372 | case Instruction::PHI: { |
| 7373 | auto *Phi = cast<PHINode>(I); |
| 7374 | |
| 7375 | // First-order recurrences are replaced by vector shuffles inside the loop. |
| 7376 | // NOTE: Don't use ToVectorTy as SK_ExtractSubvector expects a vector type. |
| 7377 | if (VF.isVector() && Legal->isFirstOrderRecurrence(Phi)) |
| 7378 | return TTI.getShuffleCost( |
| 7379 | TargetTransformInfo::SK_ExtractSubvector, cast<VectorType>(VectorTy), |
| 7380 | None, VF.getKnownMinValue() - 1, FixedVectorType::get(RetTy, 1)); |
| 7381 | |
| 7382 | // Phi nodes in non-header blocks (not inductions, reductions, etc.) are |
| 7383 | // converted into select instructions. We require N - 1 selects per phi |
| 7384 | // node, where N is the number of incoming values. |
| 7385 | if (VF.isVector() && Phi->getParent() != TheLoop->getHeader()) |
| 7386 | return (Phi->getNumIncomingValues() - 1) * |
| 7387 | TTI.getCmpSelInstrCost( |
| 7388 | Instruction::Select, ToVectorTy(Phi->getType(), VF), |
| 7389 | ToVectorTy(Type::getInt1Ty(Phi->getContext()), VF), |
| 7390 | CmpInst::BAD_ICMP_PREDICATE, CostKind); |
| 7391 | |
| 7392 | return TTI.getCFInstrCost(Instruction::PHI, CostKind); |
| 7393 | } |
| 7394 | case Instruction::UDiv: |
| 7395 | case Instruction::SDiv: |
| 7396 | case Instruction::URem: |
| 7397 | case Instruction::SRem: |
| 7398 | // If we have a predicated instruction, it may not be executed for each |
| 7399 | // vector lane. Get the scalarization cost and scale this amount by the |
| 7400 | // probability of executing the predicated block. If the instruction is not |
| 7401 | // predicated, we fall through to the next case. |
| 7402 | if (VF.isVector() && isScalarWithPredication(I, VF)) { |
| 7403 | InstructionCost Cost = 0; |
| 7404 | |
| 7405 | // These instructions have a non-void type, so account for the phi nodes |
| 7406 | // that we will create. This cost is likely to be zero. The phi node |
| 7407 | // cost, if any, should be scaled by the block probability because it |
| 7408 | // models a copy at the end of each predicated block. |
| 7409 | Cost += VF.getKnownMinValue() * |
| 7410 | TTI.getCFInstrCost(Instruction::PHI, CostKind); |
| 7411 | |
| 7412 | // The cost of the non-predicated instruction. |
| 7413 | Cost += VF.getKnownMinValue() * |
| 7414 | TTI.getArithmeticInstrCost(I->getOpcode(), RetTy, CostKind); |
| 7415 | |
| 7416 | // The cost of insertelement and extractelement instructions needed for |
| 7417 | // scalarization. |
| 7418 | Cost += getScalarizationOverhead(I, VF); |
| 7419 | |
| 7420 | // Scale the cost by the probability of executing the predicated blocks. |
| 7421 | // This assumes the predicated block for each vector lane is equally |
| 7422 | // likely. |
| 7423 | return Cost / getReciprocalPredBlockProb(); |
| 7424 | } |
| 7425 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
| 7426 | case Instruction::Add: |
| 7427 | case Instruction::FAdd: |
| 7428 | case Instruction::Sub: |
| 7429 | case Instruction::FSub: |
| 7430 | case Instruction::Mul: |
| 7431 | case Instruction::FMul: |
| 7432 | case Instruction::FDiv: |
| 7433 | case Instruction::FRem: |
| 7434 | case Instruction::Shl: |
| 7435 | case Instruction::LShr: |
| 7436 | case Instruction::AShr: |
| 7437 | case Instruction::And: |
| 7438 | case Instruction::Or: |
| 7439 | case Instruction::Xor: { |
| 7440 | // Since we will replace the stride by 1 the multiplication should go away. |
| 7441 | if (I->getOpcode() == Instruction::Mul && isStrideMul(I, Legal)) |
| 7442 | return 0; |
| 7443 | |
| 7444 | // Detect reduction patterns |
| 7445 | if (auto RedCost = getReductionPatternCost(I, VF, VectorTy, CostKind)) |
| 7446 | return *RedCost; |
| 7447 | |
| 7448 | // Certain instructions can be cheaper to vectorize if they have a constant |
| 7449 | // second vector operand. One example of this are shifts on x86. |
| 7450 | Value *Op2 = I->getOperand(1); |
| 7451 | TargetTransformInfo::OperandValueProperties Op2VP; |
| 7452 | TargetTransformInfo::OperandValueKind Op2VK = |
| 7453 | TTI.getOperandInfo(Op2, Op2VP); |
| 7454 | if (Op2VK == TargetTransformInfo::OK_AnyValue && Legal->isUniform(Op2)) |
| 7455 | Op2VK = TargetTransformInfo::OK_UniformValue; |
| 7456 | |
| 7457 | SmallVector<const Value *, 4> Operands(I->operand_values()); |
| 7458 | return TTI.getArithmeticInstrCost( |
| 7459 | I->getOpcode(), VectorTy, CostKind, TargetTransformInfo::OK_AnyValue, |
| 7460 | Op2VK, TargetTransformInfo::OP_None, Op2VP, Operands, I); |
| 7461 | } |
| 7462 | case Instruction::FNeg: { |
| 7463 | return TTI.getArithmeticInstrCost( |
| 7464 | I->getOpcode(), VectorTy, CostKind, TargetTransformInfo::OK_AnyValue, |
| 7465 | TargetTransformInfo::OK_AnyValue, TargetTransformInfo::OP_None, |
| 7466 | TargetTransformInfo::OP_None, I->getOperand(0), I); |
| 7467 | } |
| 7468 | case Instruction::Select: { |
| 7469 | SelectInst *SI = cast<SelectInst>(I); |
| 7470 | const SCEV *CondSCEV = SE->getSCEV(SI->getCondition()); |
| 7471 | bool ScalarCond = (SE->isLoopInvariant(CondSCEV, TheLoop)); |
| 7472 | |
| 7473 | const Value *Op0, *Op1; |
| 7474 | using namespace llvm::PatternMatch; |
| 7475 | if (!ScalarCond && (match(I, m_LogicalAnd(m_Value(Op0), m_Value(Op1))) || |
| 7476 | match(I, m_LogicalOr(m_Value(Op0), m_Value(Op1))))) { |
| 7477 | // select x, y, false --> x & y |
| 7478 | // select x, true, y --> x | y |
| 7479 | TTI::OperandValueProperties Op1VP = TTI::OP_None; |
| 7480 | TTI::OperandValueProperties Op2VP = TTI::OP_None; |
| 7481 | TTI::OperandValueKind Op1VK = TTI::getOperandInfo(Op0, Op1VP); |
| 7482 | TTI::OperandValueKind Op2VK = TTI::getOperandInfo(Op1, Op2VP); |
| 7483 | assert(Op0->getType()->getScalarSizeInBits() == 1 &&(static_cast <bool> (Op0->getType()->getScalarSizeInBits () == 1 && Op1->getType()->getScalarSizeInBits( ) == 1) ? void (0) : __assert_fail ("Op0->getType()->getScalarSizeInBits() == 1 && Op1->getType()->getScalarSizeInBits() == 1" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7484, __extension__ __PRETTY_FUNCTION__)) |
| 7484 | Op1->getType()->getScalarSizeInBits() == 1)(static_cast <bool> (Op0->getType()->getScalarSizeInBits () == 1 && Op1->getType()->getScalarSizeInBits( ) == 1) ? void (0) : __assert_fail ("Op0->getType()->getScalarSizeInBits() == 1 && Op1->getType()->getScalarSizeInBits() == 1" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7484, __extension__ __PRETTY_FUNCTION__)); |
| 7485 | |
| 7486 | SmallVector<const Value *, 2> Operands{Op0, Op1}; |
| 7487 | return TTI.getArithmeticInstrCost( |
| 7488 | match(I, m_LogicalOr()) ? Instruction::Or : Instruction::And, VectorTy, |
| 7489 | CostKind, Op1VK, Op2VK, Op1VP, Op2VP, Operands, I); |
| 7490 | } |
| 7491 | |
| 7492 | Type *CondTy = SI->getCondition()->getType(); |
| 7493 | if (!ScalarCond) |
| 7494 | CondTy = VectorType::get(CondTy, VF); |
| 7495 | |
| 7496 | CmpInst::Predicate Pred = CmpInst::BAD_ICMP_PREDICATE; |
| 7497 | if (auto *Cmp = dyn_cast<CmpInst>(SI->getCondition())) |
| 7498 | Pred = Cmp->getPredicate(); |
| 7499 | return TTI.getCmpSelInstrCost(I->getOpcode(), VectorTy, CondTy, Pred, |
| 7500 | CostKind, I); |
| 7501 | } |
| 7502 | case Instruction::ICmp: |
| 7503 | case Instruction::FCmp: { |
| 7504 | Type *ValTy = I->getOperand(0)->getType(); |
| 7505 | Instruction *Op0AsInstruction = dyn_cast<Instruction>(I->getOperand(0)); |
| 7506 | if (canTruncateToMinimalBitwidth(Op0AsInstruction, VF)) |
| 7507 | ValTy = IntegerType::get(ValTy->getContext(), MinBWs[Op0AsInstruction]); |
| 7508 | VectorTy = ToVectorTy(ValTy, VF); |
| 7509 | return TTI.getCmpSelInstrCost(I->getOpcode(), VectorTy, nullptr, |
| 7510 | cast<CmpInst>(I)->getPredicate(), CostKind, |
| 7511 | I); |
| 7512 | } |
| 7513 | case Instruction::Store: |
| 7514 | case Instruction::Load: { |
| 7515 | ElementCount Width = VF; |
| 7516 | if (Width.isVector()) { |
| 7517 | InstWidening Decision = getWideningDecision(I, Width); |
| 7518 | assert(Decision != CM_Unknown &&(static_cast <bool> (Decision != CM_Unknown && "CM decision should be taken at this point" ) ? void (0) : __assert_fail ("Decision != CM_Unknown && \"CM decision should be taken at this point\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7519, __extension__ __PRETTY_FUNCTION__)) |
| 7519 | "CM decision should be taken at this point")(static_cast <bool> (Decision != CM_Unknown && "CM decision should be taken at this point" ) ? void (0) : __assert_fail ("Decision != CM_Unknown && \"CM decision should be taken at this point\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7519, __extension__ __PRETTY_FUNCTION__)); |
| 7520 | if (Decision == CM_Scalarize) |
| 7521 | Width = ElementCount::getFixed(1); |
| 7522 | } |
| 7523 | VectorTy = ToVectorTy(getLoadStoreType(I), Width); |
| 7524 | return getMemoryInstructionCost(I, VF); |
| 7525 | } |
| 7526 | case Instruction::BitCast: |
| 7527 | if (I->getType()->isPointerTy()) |
| 7528 | return 0; |
| 7529 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
| 7530 | case Instruction::ZExt: |
| 7531 | case Instruction::SExt: |
| 7532 | case Instruction::FPToUI: |
| 7533 | case Instruction::FPToSI: |
| 7534 | case Instruction::FPExt: |
| 7535 | case Instruction::PtrToInt: |
| 7536 | case Instruction::IntToPtr: |
| 7537 | case Instruction::SIToFP: |
| 7538 | case Instruction::UIToFP: |
| 7539 | case Instruction::Trunc: |
| 7540 | case Instruction::FPTrunc: { |
| 7541 | // Computes the CastContextHint from a Load/Store instruction. |
| 7542 | auto ComputeCCH = [&](Instruction *I) -> TTI::CastContextHint { |
| 7543 | assert((isa<LoadInst>(I) || isa<StoreInst>(I)) &&(static_cast <bool> ((isa<LoadInst>(I) || isa< StoreInst>(I)) && "Expected a load or a store!") ? void (0) : __assert_fail ("(isa<LoadInst>(I) || isa<StoreInst>(I)) && \"Expected a load or a store!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7544, __extension__ __PRETTY_FUNCTION__)) |
| 7544 | "Expected a load or a store!")(static_cast <bool> ((isa<LoadInst>(I) || isa< StoreInst>(I)) && "Expected a load or a store!") ? void (0) : __assert_fail ("(isa<LoadInst>(I) || isa<StoreInst>(I)) && \"Expected a load or a store!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7544, __extension__ __PRETTY_FUNCTION__)); |
| 7545 | |
| 7546 | if (VF.isScalar() || !TheLoop->contains(I)) |
| 7547 | return TTI::CastContextHint::Normal; |
| 7548 | |
| 7549 | switch (getWideningDecision(I, VF)) { |
| 7550 | case LoopVectorizationCostModel::CM_GatherScatter: |
| 7551 | return TTI::CastContextHint::GatherScatter; |
| 7552 | case LoopVectorizationCostModel::CM_Interleave: |
| 7553 | return TTI::CastContextHint::Interleave; |
| 7554 | case LoopVectorizationCostModel::CM_Scalarize: |
| 7555 | case LoopVectorizationCostModel::CM_Widen: |
| 7556 | return Legal->isMaskRequired(I) ? TTI::CastContextHint::Masked |
| 7557 | : TTI::CastContextHint::Normal; |
| 7558 | case LoopVectorizationCostModel::CM_Widen_Reverse: |
| 7559 | return TTI::CastContextHint::Reversed; |
| 7560 | case LoopVectorizationCostModel::CM_Unknown: |
| 7561 | llvm_unreachable("Instr did not go through cost modelling?")::llvm::llvm_unreachable_internal("Instr did not go through cost modelling?" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7561); |
| 7562 | } |
| 7563 | |
| 7564 | llvm_unreachable("Unhandled case!")::llvm::llvm_unreachable_internal("Unhandled case!", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 7564); |
| 7565 | }; |
| 7566 | |
| 7567 | unsigned Opcode = I->getOpcode(); |
| 7568 | TTI::CastContextHint CCH = TTI::CastContextHint::None; |
| 7569 | // For Trunc, the context is the only user, which must be a StoreInst. |
| 7570 | if (Opcode == Instruction::Trunc || Opcode == Instruction::FPTrunc) { |
| 7571 | if (I->hasOneUse()) |
| 7572 | if (StoreInst *Store = dyn_cast<StoreInst>(*I->user_begin())) |
| 7573 | CCH = ComputeCCH(Store); |
| 7574 | } |
| 7575 | // For Z/Sext, the context is the operand, which must be a LoadInst. |
| 7576 | else if (Opcode == Instruction::ZExt || Opcode == Instruction::SExt || |
| 7577 | Opcode == Instruction::FPExt) { |
| 7578 | if (LoadInst *Load = dyn_cast<LoadInst>(I->getOperand(0))) |
| 7579 | CCH = ComputeCCH(Load); |
| 7580 | } |
| 7581 | |
| 7582 | // We optimize the truncation of induction variables having constant |
| 7583 | // integer steps. The cost of these truncations is the same as the scalar |
| 7584 | // operation. |
| 7585 | if (isOptimizableIVTruncate(I, VF)) { |
| 7586 | auto *Trunc = cast<TruncInst>(I); |
| 7587 | return TTI.getCastInstrCost(Instruction::Trunc, Trunc->getDestTy(), |
| 7588 | Trunc->getSrcTy(), CCH, CostKind, Trunc); |
| 7589 | } |
| 7590 | |
| 7591 | // Detect reduction patterns |
| 7592 | if (auto RedCost = getReductionPatternCost(I, VF, VectorTy, CostKind)) |
| 7593 | return *RedCost; |
| 7594 | |
| 7595 | Type *SrcScalarTy = I->getOperand(0)->getType(); |
| 7596 | Type *SrcVecTy = |
| 7597 | VectorTy->isVectorTy() ? ToVectorTy(SrcScalarTy, VF) : SrcScalarTy; |
| 7598 | if (canTruncateToMinimalBitwidth(I, VF)) { |
| 7599 | // This cast is going to be shrunk. This may remove the cast or it might |
| 7600 | // turn it into slightly different cast. For example, if MinBW == 16, |
| 7601 | // "zext i8 %1 to i32" becomes "zext i8 %1 to i16". |
| 7602 | // |
| 7603 | // Calculate the modified src and dest types. |
| 7604 | Type *MinVecTy = VectorTy; |
| 7605 | if (Opcode == Instruction::Trunc) { |
| 7606 | SrcVecTy = smallestIntegerVectorType(SrcVecTy, MinVecTy); |
| 7607 | VectorTy = |
| 7608 | largestIntegerVectorType(ToVectorTy(I->getType(), VF), MinVecTy); |
| 7609 | } else if (Opcode == Instruction::ZExt || Opcode == Instruction::SExt) { |
| 7610 | SrcVecTy = largestIntegerVectorType(SrcVecTy, MinVecTy); |
| 7611 | VectorTy = |
| 7612 | smallestIntegerVectorType(ToVectorTy(I->getType(), VF), MinVecTy); |
| 7613 | } |
| 7614 | } |
| 7615 | |
| 7616 | return TTI.getCastInstrCost(Opcode, VectorTy, SrcVecTy, CCH, CostKind, I); |
| 7617 | } |
| 7618 | case Instruction::Call: { |
| 7619 | if (RecurrenceDescriptor::isFMulAddIntrinsic(I)) |
| 7620 | if (auto RedCost = getReductionPatternCost(I, VF, VectorTy, CostKind)) |
| 7621 | return *RedCost; |
| 7622 | bool NeedToScalarize; |
| 7623 | CallInst *CI = cast<CallInst>(I); |
| 7624 | InstructionCost CallCost = getVectorCallCost(CI, VF, NeedToScalarize); |
| 7625 | if (getVectorIntrinsicIDForCall(CI, TLI)) { |
| 7626 | InstructionCost IntrinsicCost = getVectorIntrinsicCost(CI, VF); |
| 7627 | return std::min(CallCost, IntrinsicCost); |
| 7628 | } |
| 7629 | return CallCost; |
| 7630 | } |
| 7631 | case Instruction::ExtractValue: |
| 7632 | return TTI.getInstructionCost(I, TTI::TCK_RecipThroughput); |
| 7633 | case Instruction::Alloca: |
| 7634 | // We cannot easily widen alloca to a scalable alloca, as |
| 7635 | // the result would need to be a vector of pointers. |
| 7636 | if (VF.isScalable()) |
| 7637 | return InstructionCost::getInvalid(); |
| 7638 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; |
| 7639 | default: |
| 7640 | // This opcode is unknown. Assume that it is the same as 'mul'. |
| 7641 | return TTI.getArithmeticInstrCost(Instruction::Mul, VectorTy, CostKind); |
| 7642 | } // end of switch. |
| 7643 | } |
| 7644 | |
| 7645 | char LoopVectorize::ID = 0; |
| 7646 | |
| 7647 | static const char lv_name[] = "Loop Vectorization"; |
| 7648 | |
| 7649 | INITIALIZE_PASS_BEGIN(LoopVectorize, LV_NAME, lv_name, false, false)static void *initializeLoopVectorizePassOnce(PassRegistry & Registry) { |
| 7650 | INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)initializeTargetTransformInfoWrapperPassPass(Registry); |
| 7651 | INITIALIZE_PASS_DEPENDENCY(BasicAAWrapperPass)initializeBasicAAWrapperPassPass(Registry); |
| 7652 | INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)initializeAAResultsWrapperPassPass(Registry); |
| 7653 | INITIALIZE_PASS_DEPENDENCY(GlobalsAAWrapperPass)initializeGlobalsAAWrapperPassPass(Registry); |
| 7654 | INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)initializeAssumptionCacheTrackerPass(Registry); |
| 7655 | INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass)initializeBlockFrequencyInfoWrapperPassPass(Registry); |
| 7656 | INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)initializeDominatorTreeWrapperPassPass(Registry); |
| 7657 | INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)initializeScalarEvolutionWrapperPassPass(Registry); |
| 7658 | INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)initializeLoopInfoWrapperPassPass(Registry); |
| 7659 | INITIALIZE_PASS_DEPENDENCY(LoopAccessLegacyAnalysis)initializeLoopAccessLegacyAnalysisPass(Registry); |
| 7660 | INITIALIZE_PASS_DEPENDENCY(DemandedBitsWrapperPass)initializeDemandedBitsWrapperPassPass(Registry); |
| 7661 | INITIALIZE_PASS_DEPENDENCY(OptimizationRemarkEmitterWrapperPass)initializeOptimizationRemarkEmitterWrapperPassPass(Registry); |
| 7662 | INITIALIZE_PASS_DEPENDENCY(ProfileSummaryInfoWrapperPass)initializeProfileSummaryInfoWrapperPassPass(Registry); |
| 7663 | INITIALIZE_PASS_DEPENDENCY(InjectTLIMappingsLegacy)initializeInjectTLIMappingsLegacyPass(Registry); |
| 7664 | INITIALIZE_PASS_END(LoopVectorize, LV_NAME, lv_name, false, false)PassInfo *PI = new PassInfo( lv_name, "loop-vectorize", & LoopVectorize::ID, PassInfo::NormalCtor_t(callDefaultCtor< LoopVectorize>), false, false); Registry.registerPass(*PI, true); return PI; } static llvm::once_flag InitializeLoopVectorizePassFlag ; void llvm::initializeLoopVectorizePass(PassRegistry &Registry ) { llvm::call_once(InitializeLoopVectorizePassFlag, initializeLoopVectorizePassOnce , std::ref(Registry)); } |
| 7665 | |
| 7666 | namespace llvm { |
| 7667 | |
| 7668 | Pass *createLoopVectorizePass() { return new LoopVectorize(); } |
| 7669 | |
| 7670 | Pass *createLoopVectorizePass(bool InterleaveOnlyWhenForced, |
| 7671 | bool VectorizeOnlyWhenForced) { |
| 7672 | return new LoopVectorize(InterleaveOnlyWhenForced, VectorizeOnlyWhenForced); |
| 7673 | } |
| 7674 | |
| 7675 | } // end namespace llvm |
| 7676 | |
| 7677 | bool LoopVectorizationCostModel::isConsecutiveLoadOrStore(Instruction *Inst) { |
| 7678 | // Check if the pointer operand of a load or store instruction is |
| 7679 | // consecutive. |
| 7680 | if (auto *Ptr = getLoadStorePointerOperand(Inst)) |
| 7681 | return Legal->isConsecutivePtr(getLoadStoreType(Inst), Ptr); |
| 7682 | return false; |
| 7683 | } |
| 7684 | |
| 7685 | void LoopVectorizationCostModel::collectValuesToIgnore() { |
| 7686 | // Ignore ephemeral values. |
| 7687 | CodeMetrics::collectEphemeralValues(TheLoop, AC, ValuesToIgnore); |
| 7688 | |
| 7689 | // Ignore type-promoting instructions we identified during reduction |
| 7690 | // detection. |
| 7691 | for (auto &Reduction : Legal->getReductionVars()) { |
| 7692 | const RecurrenceDescriptor &RedDes = Reduction.second; |
| 7693 | const SmallPtrSetImpl<Instruction *> &Casts = RedDes.getCastInsts(); |
| 7694 | VecValuesToIgnore.insert(Casts.begin(), Casts.end()); |
| 7695 | } |
| 7696 | // Ignore type-casting instructions we identified during induction |
| 7697 | // detection. |
| 7698 | for (auto &Induction : Legal->getInductionVars()) { |
| 7699 | const InductionDescriptor &IndDes = Induction.second; |
| 7700 | const SmallVectorImpl<Instruction *> &Casts = IndDes.getCastInsts(); |
| 7701 | VecValuesToIgnore.insert(Casts.begin(), Casts.end()); |
| 7702 | } |
| 7703 | } |
| 7704 | |
| 7705 | void LoopVectorizationCostModel::collectInLoopReductions() { |
| 7706 | for (auto &Reduction : Legal->getReductionVars()) { |
| 7707 | PHINode *Phi = Reduction.first; |
| 7708 | const RecurrenceDescriptor &RdxDesc = Reduction.second; |
| 7709 | |
| 7710 | // We don't collect reductions that are type promoted (yet). |
| 7711 | if (RdxDesc.getRecurrenceType() != Phi->getType()) |
| 7712 | continue; |
| 7713 | |
| 7714 | // If the target would prefer this reduction to happen "in-loop", then we |
| 7715 | // want to record it as such. |
| 7716 | unsigned Opcode = RdxDesc.getOpcode(); |
| 7717 | if (!PreferInLoopReductions && !useOrderedReductions(RdxDesc) && |
| 7718 | !TTI.preferInLoopReduction(Opcode, Phi->getType(), |
| 7719 | TargetTransformInfo::ReductionFlags())) |
| 7720 | continue; |
| 7721 | |
| 7722 | // Check that we can correctly put the reductions into the loop, by |
| 7723 | // finding the chain of operations that leads from the phi to the loop |
| 7724 | // exit value. |
| 7725 | SmallVector<Instruction *, 4> ReductionOperations = |
| 7726 | RdxDesc.getReductionOpChain(Phi, TheLoop); |
| 7727 | bool InLoop = !ReductionOperations.empty(); |
| 7728 | if (InLoop) { |
| 7729 | InLoopReductionChains[Phi] = ReductionOperations; |
| 7730 | // Add the elements to InLoopReductionImmediateChains for cost modelling. |
| 7731 | Instruction *LastChain = Phi; |
| 7732 | for (auto *I : ReductionOperations) { |
| 7733 | InLoopReductionImmediateChains[I] = LastChain; |
| 7734 | LastChain = I; |
| 7735 | } |
| 7736 | } |
| 7737 | LLVM_DEBUG(dbgs() << "LV: Using " << (InLoop ? "inloop" : "out of loop")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Using " << ( InLoop ? "inloop" : "out of loop") << " reduction for phi: " << *Phi << "\n"; } } while (false) |
| 7738 | << " reduction for phi: " << *Phi << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Using " << ( InLoop ? "inloop" : "out of loop") << " reduction for phi: " << *Phi << "\n"; } } while (false); |
| 7739 | } |
| 7740 | } |
| 7741 | |
| 7742 | // TODO: we could return a pair of values that specify the max VF and |
| 7743 | // min VF, to be used in `buildVPlans(MinVF, MaxVF)` instead of |
| 7744 | // `buildVPlans(VF, VF)`. We cannot do it because VPLAN at the moment |
| 7745 | // doesn't have a cost model that can choose which plan to execute if |
| 7746 | // more than one is generated. |
| 7747 | static unsigned determineVPlanVF(const unsigned WidestVectorRegBits, |
| 7748 | LoopVectorizationCostModel &CM) { |
| 7749 | unsigned WidestType; |
| 7750 | std::tie(std::ignore, WidestType) = CM.getSmallestAndWidestTypes(); |
| 7751 | return WidestVectorRegBits / WidestType; |
| 7752 | } |
| 7753 | |
| 7754 | VectorizationFactor |
| 7755 | LoopVectorizationPlanner::planInVPlanNativePath(ElementCount UserVF) { |
| 7756 | assert(!UserVF.isScalable() && "scalable vectors not yet supported")(static_cast <bool> (!UserVF.isScalable() && "scalable vectors not yet supported" ) ? void (0) : __assert_fail ("!UserVF.isScalable() && \"scalable vectors not yet supported\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7756, __extension__ __PRETTY_FUNCTION__)); |
| 7757 | ElementCount VF = UserVF; |
| 7758 | // Outer loop handling: They may require CFG and instruction level |
| 7759 | // transformations before even evaluating whether vectorization is profitable. |
| 7760 | // Since we cannot modify the incoming IR, we need to build VPlan upfront in |
| 7761 | // the vectorization pipeline. |
| 7762 | if (!OrigLoop->isInnermost()) { |
| 7763 | // If the user doesn't provide a vectorization factor, determine a |
| 7764 | // reasonable one. |
| 7765 | if (UserVF.isZero()) { |
| 7766 | VF = ElementCount::getFixed(determineVPlanVF( |
| 7767 | TTI->getRegisterBitWidth(TargetTransformInfo::RGK_FixedWidthVector) |
| 7768 | .getFixedSize(), |
| 7769 | CM)); |
| 7770 | LLVM_DEBUG(dbgs() << "LV: VPlan computed VF " << VF << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: VPlan computed VF " << VF << ".\n"; } } while (false); |
| 7771 | |
| 7772 | // Make sure we have a VF > 1 for stress testing. |
| 7773 | if (VPlanBuildStressTest && (VF.isScalar() || VF.isZero())) { |
| 7774 | LLVM_DEBUG(dbgs() << "LV: VPlan stress testing: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: VPlan stress testing: " << "overriding computed VF.\n"; } } while (false) |
| 7775 | << "overriding computed VF.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: VPlan stress testing: " << "overriding computed VF.\n"; } } while (false); |
| 7776 | VF = ElementCount::getFixed(4); |
| 7777 | } |
| 7778 | } |
| 7779 | assert(EnableVPlanNativePath && "VPlan-native path is not enabled.")(static_cast <bool> (EnableVPlanNativePath && "VPlan-native path is not enabled." ) ? void (0) : __assert_fail ("EnableVPlanNativePath && \"VPlan-native path is not enabled.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7779, __extension__ __PRETTY_FUNCTION__)); |
| 7780 | assert(isPowerOf2_32(VF.getKnownMinValue()) &&(static_cast <bool> (isPowerOf2_32(VF.getKnownMinValue( )) && "VF needs to be a power of two") ? void (0) : __assert_fail ("isPowerOf2_32(VF.getKnownMinValue()) && \"VF needs to be a power of two\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7781, __extension__ __PRETTY_FUNCTION__)) |
| 7781 | "VF needs to be a power of two")(static_cast <bool> (isPowerOf2_32(VF.getKnownMinValue( )) && "VF needs to be a power of two") ? void (0) : __assert_fail ("isPowerOf2_32(VF.getKnownMinValue()) && \"VF needs to be a power of two\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7781, __extension__ __PRETTY_FUNCTION__)); |
| 7782 | LLVM_DEBUG(dbgs() << "LV: Using " << (!UserVF.isZero() ? "user " : "")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Using " << ( !UserVF.isZero() ? "user " : "") << "VF " << VF << " to build VPlans.\n"; } } while (false) |
| 7783 | << "VF " << VF << " to build VPlans.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Using " << ( !UserVF.isZero() ? "user " : "") << "VF " << VF << " to build VPlans.\n"; } } while (false); |
| 7784 | buildVPlans(VF, VF); |
| 7785 | |
| 7786 | // For VPlan build stress testing, we bail out after VPlan construction. |
| 7787 | if (VPlanBuildStressTest) |
| 7788 | return VectorizationFactor::Disabled(); |
| 7789 | |
| 7790 | return {VF, 0 /*Cost*/}; |
| 7791 | } |
| 7792 | |
| 7793 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not vectorizing. Inner loops aren't supported in the " "VPlan-native path.\n"; } } while (false) |
| 7794 | dbgs() << "LV: Not vectorizing. Inner loops aren't supported in the "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not vectorizing. Inner loops aren't supported in the " "VPlan-native path.\n"; } } while (false) |
| 7795 | "VPlan-native path.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not vectorizing. Inner loops aren't supported in the " "VPlan-native path.\n"; } } while (false); |
| 7796 | return VectorizationFactor::Disabled(); |
| 7797 | } |
| 7798 | |
| 7799 | Optional<VectorizationFactor> |
| 7800 | LoopVectorizationPlanner::plan(ElementCount UserVF, unsigned UserIC) { |
| 7801 | assert(OrigLoop->isInnermost() && "Inner loop expected.")(static_cast <bool> (OrigLoop->isInnermost() && "Inner loop expected.") ? void (0) : __assert_fail ("OrigLoop->isInnermost() && \"Inner loop expected.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7801, __extension__ __PRETTY_FUNCTION__)); |
| 7802 | FixedScalableVFPair MaxFactors = CM.computeMaxVF(UserVF, UserIC); |
| 7803 | if (!MaxFactors) // Cases that should not to be vectorized nor interleaved. |
| 7804 | return None; |
| 7805 | |
| 7806 | // Invalidate interleave groups if all blocks of loop will be predicated. |
| 7807 | if (CM.blockNeedsPredicationForAnyReason(OrigLoop->getHeader()) && |
| 7808 | !useMaskedInterleavedAccesses(*TTI)) { |
| 7809 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Invalidate all interleaved groups due to fold-tail by masking " "which requires masked-interleaved support.\n"; } } while (false ) |
| 7810 | dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Invalidate all interleaved groups due to fold-tail by masking " "which requires masked-interleaved support.\n"; } } while (false ) |
| 7811 | << "LV: Invalidate all interleaved groups due to fold-tail by masking "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Invalidate all interleaved groups due to fold-tail by masking " "which requires masked-interleaved support.\n"; } } while (false ) |
| 7812 | "which requires masked-interleaved support.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Invalidate all interleaved groups due to fold-tail by masking " "which requires masked-interleaved support.\n"; } } while (false ); |
| 7813 | if (CM.InterleaveInfo.invalidateGroups()) |
| 7814 | // Invalidating interleave groups also requires invalidating all decisions |
| 7815 | // based on them, which includes widening decisions and uniform and scalar |
| 7816 | // values. |
| 7817 | CM.invalidateCostModelingDecisions(); |
| 7818 | } |
| 7819 | |
| 7820 | ElementCount MaxUserVF = |
| 7821 | UserVF.isScalable() ? MaxFactors.ScalableVF : MaxFactors.FixedVF; |
| 7822 | bool UserVFIsLegal = ElementCount::isKnownLE(UserVF, MaxUserVF); |
| 7823 | if (!UserVF.isZero() && UserVFIsLegal) { |
| 7824 | assert(isPowerOf2_32(UserVF.getKnownMinValue()) &&(static_cast <bool> (isPowerOf2_32(UserVF.getKnownMinValue ()) && "VF needs to be a power of two") ? void (0) : __assert_fail ("isPowerOf2_32(UserVF.getKnownMinValue()) && \"VF needs to be a power of two\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7825, __extension__ __PRETTY_FUNCTION__)) |
| 7825 | "VF needs to be a power of two")(static_cast <bool> (isPowerOf2_32(UserVF.getKnownMinValue ()) && "VF needs to be a power of two") ? void (0) : __assert_fail ("isPowerOf2_32(UserVF.getKnownMinValue()) && \"VF needs to be a power of two\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7825, __extension__ __PRETTY_FUNCTION__)); |
| 7826 | // Collect the instructions (and their associated costs) that will be more |
| 7827 | // profitable to scalarize. |
| 7828 | if (CM.selectUserVectorizationFactor(UserVF)) { |
| 7829 | LLVM_DEBUG(dbgs() << "LV: Using user VF " << UserVF << ".\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Using user VF " << UserVF << ".\n"; } } while (false); |
| 7830 | CM.collectInLoopReductions(); |
| 7831 | buildVPlansWithVPRecipes(UserVF, UserVF); |
| 7832 | LLVM_DEBUG(printPlans(dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { printPlans(dbgs()); } } while (false); |
| 7833 | return {{UserVF, 0}}; |
| 7834 | } else |
| 7835 | reportVectorizationInfo("UserVF ignored because of invalid costs.", |
| 7836 | "InvalidCost", ORE, OrigLoop); |
| 7837 | } |
| 7838 | |
| 7839 | // Populate the set of Vectorization Factor Candidates. |
| 7840 | ElementCountSet VFCandidates; |
| 7841 | for (auto VF = ElementCount::getFixed(1); |
| 7842 | ElementCount::isKnownLE(VF, MaxFactors.FixedVF); VF *= 2) |
| 7843 | VFCandidates.insert(VF); |
| 7844 | for (auto VF = ElementCount::getScalable(1); |
| 7845 | ElementCount::isKnownLE(VF, MaxFactors.ScalableVF); VF *= 2) |
| 7846 | VFCandidates.insert(VF); |
| 7847 | |
| 7848 | for (const auto &VF : VFCandidates) { |
| 7849 | // Collect Uniform and Scalar instructions after vectorization with VF. |
| 7850 | CM.collectUniformsAndScalars(VF); |
| 7851 | |
| 7852 | // Collect the instructions (and their associated costs) that will be more |
| 7853 | // profitable to scalarize. |
| 7854 | if (VF.isVector()) |
| 7855 | CM.collectInstsToScalarize(VF); |
| 7856 | } |
| 7857 | |
| 7858 | CM.collectInLoopReductions(); |
| 7859 | buildVPlansWithVPRecipes(ElementCount::getFixed(1), MaxFactors.FixedVF); |
| 7860 | buildVPlansWithVPRecipes(ElementCount::getScalable(1), MaxFactors.ScalableVF); |
| 7861 | |
| 7862 | LLVM_DEBUG(printPlans(dbgs()))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { printPlans(dbgs()); } } while (false); |
| 7863 | if (!MaxFactors.hasVector()) |
| 7864 | return VectorizationFactor::Disabled(); |
| 7865 | |
| 7866 | // Select the optimal vectorization factor. |
| 7867 | auto SelectedVF = CM.selectVectorizationFactor(VFCandidates); |
| 7868 | |
| 7869 | // Check if it is profitable to vectorize with runtime checks. |
| 7870 | unsigned NumRuntimePointerChecks = Requirements.getNumRuntimePointerChecks(); |
| 7871 | if (SelectedVF.Width.getKnownMinValue() > 1 && NumRuntimePointerChecks) { |
| 7872 | bool PragmaThresholdReached = |
| 7873 | NumRuntimePointerChecks > PragmaVectorizeMemoryCheckThreshold; |
| 7874 | bool ThresholdReached = |
| 7875 | NumRuntimePointerChecks > VectorizerParams::RuntimeMemoryCheckThreshold; |
| 7876 | if ((ThresholdReached && !Hints.allowReordering()) || |
| 7877 | PragmaThresholdReached) { |
| 7878 | ORE->emit([&]() { |
| 7879 | return OptimizationRemarkAnalysisAliasing( |
| 7880 | DEBUG_TYPE"loop-vectorize", "CantReorderMemOps", OrigLoop->getStartLoc(), |
| 7881 | OrigLoop->getHeader()) |
| 7882 | << "loop not vectorized: cannot prove it is safe to reorder " |
| 7883 | "memory operations"; |
| 7884 | }); |
| 7885 | LLVM_DEBUG(dbgs() << "LV: Too many memory checks needed.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Too many memory checks needed.\n" ; } } while (false); |
| 7886 | Hints.emitRemarkWithHints(); |
| 7887 | return VectorizationFactor::Disabled(); |
| 7888 | } |
| 7889 | } |
| 7890 | return SelectedVF; |
| 7891 | } |
| 7892 | |
| 7893 | VPlan &LoopVectorizationPlanner::getBestPlanFor(ElementCount VF) const { |
| 7894 | assert(count_if(VPlans,(static_cast <bool> (count_if(VPlans, [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) == 1 && "Best VF has not a single VPlan." ) ? void (0) : __assert_fail ("count_if(VPlans, [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) == 1 && \"Best VF has not a single VPlan.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7897, __extension__ __PRETTY_FUNCTION__)) |
| 7895 | [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) ==(static_cast <bool> (count_if(VPlans, [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) == 1 && "Best VF has not a single VPlan." ) ? void (0) : __assert_fail ("count_if(VPlans, [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) == 1 && \"Best VF has not a single VPlan.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7897, __extension__ __PRETTY_FUNCTION__)) |
| 7896 | 1 &&(static_cast <bool> (count_if(VPlans, [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) == 1 && "Best VF has not a single VPlan." ) ? void (0) : __assert_fail ("count_if(VPlans, [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) == 1 && \"Best VF has not a single VPlan.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7897, __extension__ __PRETTY_FUNCTION__)) |
| 7897 | "Best VF has not a single VPlan.")(static_cast <bool> (count_if(VPlans, [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) == 1 && "Best VF has not a single VPlan." ) ? void (0) : __assert_fail ("count_if(VPlans, [VF](const VPlanPtr &Plan) { return Plan->hasVF(VF); }) == 1 && \"Best VF has not a single VPlan.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 7897, __extension__ __PRETTY_FUNCTION__)); |
| 7898 | |
| 7899 | for (const VPlanPtr &Plan : VPlans) { |
| 7900 | if (Plan->hasVF(VF)) |
| 7901 | return *Plan.get(); |
| 7902 | } |
| 7903 | llvm_unreachable("No plan found!")::llvm::llvm_unreachable_internal("No plan found!", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 7903); |
| 7904 | } |
| 7905 | |
| 7906 | static void AddRuntimeUnrollDisableMetaData(Loop *L) { |
| 7907 | SmallVector<Metadata *, 4> MDs; |
| 7908 | // Reserve first location for self reference to the LoopID metadata node. |
| 7909 | MDs.push_back(nullptr); |
| 7910 | bool IsUnrollMetadata = false; |
| 7911 | MDNode *LoopID = L->getLoopID(); |
| 7912 | if (LoopID) { |
| 7913 | // First find existing loop unrolling disable metadata. |
| 7914 | for (unsigned i = 1, ie = LoopID->getNumOperands(); i < ie; ++i) { |
| 7915 | auto *MD = dyn_cast<MDNode>(LoopID->getOperand(i)); |
| 7916 | if (MD) { |
| 7917 | const auto *S = dyn_cast<MDString>(MD->getOperand(0)); |
| 7918 | IsUnrollMetadata = |
| 7919 | S && S->getString().startswith("llvm.loop.unroll.disable"); |
| 7920 | } |
| 7921 | MDs.push_back(LoopID->getOperand(i)); |
| 7922 | } |
| 7923 | } |
| 7924 | |
| 7925 | if (!IsUnrollMetadata) { |
| 7926 | // Add runtime unroll disable metadata. |
| 7927 | LLVMContext &Context = L->getHeader()->getContext(); |
| 7928 | SmallVector<Metadata *, 1> DisableOperands; |
| 7929 | DisableOperands.push_back( |
| 7930 | MDString::get(Context, "llvm.loop.unroll.runtime.disable")); |
| 7931 | MDNode *DisableNode = MDNode::get(Context, DisableOperands); |
| 7932 | MDs.push_back(DisableNode); |
| 7933 | MDNode *NewLoopID = MDNode::get(Context, MDs); |
| 7934 | // Set operand 0 to refer to the loop id itself. |
| 7935 | NewLoopID->replaceOperandWith(0, NewLoopID); |
| 7936 | L->setLoopID(NewLoopID); |
| 7937 | } |
| 7938 | } |
| 7939 | |
| 7940 | void LoopVectorizationPlanner::executePlan(ElementCount BestVF, unsigned BestUF, |
| 7941 | VPlan &BestVPlan, |
| 7942 | InnerLoopVectorizer &ILV, |
| 7943 | DominatorTree *DT) { |
| 7944 | LLVM_DEBUG(dbgs() << "Executing best plan with VF=" << BestVF << ", UF=" << BestUFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "Executing best plan with VF=" << BestVF << ", UF=" << BestUF << '\n' ; } } while (false) |
| 7945 | << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "Executing best plan with VF=" << BestVF << ", UF=" << BestUF << '\n' ; } } while (false); |
| 7946 | |
| 7947 | // Perform the actual loop transformation. |
| 7948 | |
| 7949 | // 1. Create a new empty loop. Unlink the old loop and connect the new one. |
| 7950 | VPTransformState State{BestVF, BestUF, LI, DT, ILV.Builder, &ILV, &BestVPlan}; |
| 7951 | Value *CanonicalIVStartValue; |
| 7952 | std::tie(State.CFG.PrevBB, CanonicalIVStartValue) = |
| 7953 | ILV.createVectorizedLoopSkeleton(); |
| 7954 | ILV.collectPoisonGeneratingRecipes(State); |
| 7955 | |
| 7956 | ILV.printDebugTracesAtStart(); |
| 7957 | |
| 7958 | //===------------------------------------------------===// |
| 7959 | // |
| 7960 | // Notice: any optimization or new instruction that go |
| 7961 | // into the code below should also be implemented in |
| 7962 | // the cost-model. |
| 7963 | // |
| 7964 | //===------------------------------------------------===// |
| 7965 | |
| 7966 | // 2. Copy and widen instructions from the old loop into the new loop. |
| 7967 | BestVPlan.prepareToExecute(ILV.getOrCreateTripCount(nullptr), |
| 7968 | ILV.getOrCreateVectorTripCount(nullptr), |
| 7969 | CanonicalIVStartValue, State); |
| 7970 | BestVPlan.execute(&State); |
| 7971 | |
| 7972 | // Keep all loop hints from the original loop on the vector loop (we'll |
| 7973 | // replace the vectorizer-specific hints below). |
| 7974 | MDNode *OrigLoopID = OrigLoop->getLoopID(); |
| 7975 | |
| 7976 | Optional<MDNode *> VectorizedLoopID = |
| 7977 | makeFollowupLoopID(OrigLoopID, {LLVMLoopVectorizeFollowupAll, |
| 7978 | LLVMLoopVectorizeFollowupVectorized}); |
| 7979 | |
| 7980 | Loop *L = LI->getLoopFor(State.CFG.PrevBB); |
| 7981 | if (VectorizedLoopID.hasValue()) |
| 7982 | L->setLoopID(VectorizedLoopID.getValue()); |
| 7983 | else { |
| 7984 | // Keep all loop hints from the original loop on the vector loop (we'll |
| 7985 | // replace the vectorizer-specific hints below). |
| 7986 | if (MDNode *LID = OrigLoop->getLoopID()) |
| 7987 | L->setLoopID(LID); |
| 7988 | |
| 7989 | LoopVectorizeHints Hints(L, true, *ORE); |
| 7990 | Hints.setAlreadyVectorized(); |
| 7991 | } |
| 7992 | // Disable runtime unrolling when vectorizing the epilogue loop. |
| 7993 | if (CanonicalIVStartValue) |
| 7994 | AddRuntimeUnrollDisableMetaData(L); |
| 7995 | |
| 7996 | // 3. Fix the vectorized code: take care of header phi's, live-outs, |
| 7997 | // predication, updating analyses. |
| 7998 | ILV.fixVectorizedLoop(State); |
| 7999 | |
| 8000 | ILV.printDebugTracesAtEnd(); |
| 8001 | } |
| 8002 | |
| 8003 | #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) |
| 8004 | void LoopVectorizationPlanner::printPlans(raw_ostream &O) { |
| 8005 | for (const auto &Plan : VPlans) |
| 8006 | if (PrintVPlansInDotFormat) |
| 8007 | Plan->printDOT(O); |
| 8008 | else |
| 8009 | Plan->print(O); |
| 8010 | } |
| 8011 | #endif |
| 8012 | |
| 8013 | void LoopVectorizationPlanner::collectTriviallyDeadInstructions( |
| 8014 | SmallPtrSetImpl<Instruction *> &DeadInstructions) { |
| 8015 | |
| 8016 | // We create new control-flow for the vectorized loop, so the original exit |
| 8017 | // conditions will be dead after vectorization if it's only used by the |
| 8018 | // terminator |
| 8019 | SmallVector<BasicBlock*> ExitingBlocks; |
| 8020 | OrigLoop->getExitingBlocks(ExitingBlocks); |
| 8021 | for (auto *BB : ExitingBlocks) { |
| 8022 | auto *Cmp = dyn_cast<Instruction>(BB->getTerminator()->getOperand(0)); |
| 8023 | if (!Cmp || !Cmp->hasOneUse()) |
| 8024 | continue; |
| 8025 | |
| 8026 | // TODO: we should introduce a getUniqueExitingBlocks on Loop |
| 8027 | if (!DeadInstructions.insert(Cmp).second) |
| 8028 | continue; |
| 8029 | |
| 8030 | // The operands of the icmp is often a dead trunc, used by IndUpdate. |
| 8031 | // TODO: can recurse through operands in general |
| 8032 | for (Value *Op : Cmp->operands()) { |
| 8033 | if (isa<TruncInst>(Op) && Op->hasOneUse()) |
| 8034 | DeadInstructions.insert(cast<Instruction>(Op)); |
| 8035 | } |
| 8036 | } |
| 8037 | |
| 8038 | // We create new "steps" for induction variable updates to which the original |
| 8039 | // induction variables map. An original update instruction will be dead if |
| 8040 | // all its users except the induction variable are dead. |
| 8041 | auto *Latch = OrigLoop->getLoopLatch(); |
| 8042 | for (auto &Induction : Legal->getInductionVars()) { |
| 8043 | PHINode *Ind = Induction.first; |
| 8044 | auto *IndUpdate = cast<Instruction>(Ind->getIncomingValueForBlock(Latch)); |
| 8045 | |
| 8046 | // If the tail is to be folded by masking, the primary induction variable, |
| 8047 | // if exists, isn't dead: it will be used for masking. Don't kill it. |
| 8048 | if (CM.foldTailByMasking() && IndUpdate == Legal->getPrimaryInduction()) |
| 8049 | continue; |
| 8050 | |
| 8051 | if (llvm::all_of(IndUpdate->users(), [&](User *U) -> bool { |
| 8052 | return U == Ind || DeadInstructions.count(cast<Instruction>(U)); |
| 8053 | })) |
| 8054 | DeadInstructions.insert(IndUpdate); |
| 8055 | } |
| 8056 | } |
| 8057 | |
| 8058 | Value *InnerLoopUnroller::getBroadcastInstrs(Value *V) { return V; } |
| 8059 | |
| 8060 | //===--------------------------------------------------------------------===// |
| 8061 | // EpilogueVectorizerMainLoop |
| 8062 | //===--------------------------------------------------------------------===// |
| 8063 | |
| 8064 | /// This function is partially responsible for generating the control flow |
| 8065 | /// depicted in https://llvm.org/docs/Vectorizers.html#epilogue-vectorization. |
| 8066 | std::pair<BasicBlock *, Value *> |
| 8067 | EpilogueVectorizerMainLoop::createEpilogueVectorizedLoopSkeleton() { |
| 8068 | MDNode *OrigLoopID = OrigLoop->getLoopID(); |
| 8069 | Loop *Lp = createVectorLoopSkeleton(""); |
| 8070 | |
| 8071 | // Generate the code to check the minimum iteration count of the vector |
| 8072 | // epilogue (see below). |
| 8073 | EPI.EpilogueIterationCountCheck = |
| 8074 | emitMinimumIterationCountCheck(Lp, LoopScalarPreHeader, true); |
| 8075 | EPI.EpilogueIterationCountCheck->setName("iter.check"); |
| 8076 | |
| 8077 | // Generate the code to check any assumptions that we've made for SCEV |
| 8078 | // expressions. |
| 8079 | EPI.SCEVSafetyCheck = emitSCEVChecks(Lp, LoopScalarPreHeader); |
| 8080 | |
| 8081 | // Generate the code that checks at runtime if arrays overlap. We put the |
| 8082 | // checks into a separate block to make the more common case of few elements |
| 8083 | // faster. |
| 8084 | EPI.MemSafetyCheck = emitMemRuntimeChecks(Lp, LoopScalarPreHeader); |
| 8085 | |
| 8086 | // Generate the iteration count check for the main loop, *after* the check |
| 8087 | // for the epilogue loop, so that the path-length is shorter for the case |
| 8088 | // that goes directly through the vector epilogue. The longer-path length for |
| 8089 | // the main loop is compensated for, by the gain from vectorizing the larger |
| 8090 | // trip count. Note: the branch will get updated later on when we vectorize |
| 8091 | // the epilogue. |
| 8092 | EPI.MainLoopIterationCountCheck = |
| 8093 | emitMinimumIterationCountCheck(Lp, LoopScalarPreHeader, false); |
| 8094 | |
| 8095 | // Generate the induction variable. |
| 8096 | Value *CountRoundDown = getOrCreateVectorTripCount(Lp); |
| 8097 | EPI.VectorTripCount = CountRoundDown; |
| 8098 | createHeaderBranch(Lp); |
| 8099 | |
| 8100 | // Skip induction resume value creation here because they will be created in |
| 8101 | // the second pass. If we created them here, they wouldn't be used anyway, |
| 8102 | // because the vplan in the second pass still contains the inductions from the |
| 8103 | // original loop. |
| 8104 | |
| 8105 | return {completeLoopSkeleton(Lp, OrigLoopID), nullptr}; |
| 8106 | } |
| 8107 | |
| 8108 | void EpilogueVectorizerMainLoop::printDebugTracesAtStart() { |
| 8109 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (first pass)\n" << "Main Loop VF:" << EPI.MainLoopVF << ", Main Loop UF:" << EPI.MainLoopUF << ", Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8110 | dbgs() << "Create Skeleton for epilogue vectorized loop (first pass)\n"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (first pass)\n" << "Main Loop VF:" << EPI.MainLoopVF << ", Main Loop UF:" << EPI.MainLoopUF << ", Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8111 | << "Main Loop VF:" << EPI.MainLoopVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (first pass)\n" << "Main Loop VF:" << EPI.MainLoopVF << ", Main Loop UF:" << EPI.MainLoopUF << ", Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8112 | << ", Main Loop UF:" << EPI.MainLoopUFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (first pass)\n" << "Main Loop VF:" << EPI.MainLoopVF << ", Main Loop UF:" << EPI.MainLoopUF << ", Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8113 | << ", Epilogue Loop VF:" << EPI.EpilogueVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (first pass)\n" << "Main Loop VF:" << EPI.MainLoopVF << ", Main Loop UF:" << EPI.MainLoopUF << ", Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8114 | << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (first pass)\n" << "Main Loop VF:" << EPI.MainLoopVF << ", Main Loop UF:" << EPI.MainLoopUF << ", Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8115 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (first pass)\n" << "Main Loop VF:" << EPI.MainLoopVF << ", Main Loop UF:" << EPI.MainLoopUF << ", Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false); |
| 8116 | } |
| 8117 | |
| 8118 | void EpilogueVectorizerMainLoop::printDebugTracesAtEnd() { |
| 8119 | DEBUG_WITH_TYPE(VerboseDebug, {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType (VerboseDebug)) { { dbgs() << "intermediate fn:\n" << *OrigLoop->getHeader()->getParent() << "\n"; }; } } while (false) |
| 8120 | dbgs() << "intermediate fn:\n"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType (VerboseDebug)) { { dbgs() << "intermediate fn:\n" << *OrigLoop->getHeader()->getParent() << "\n"; }; } } while (false) |
| 8121 | << *OrigLoop->getHeader()->getParent() << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType (VerboseDebug)) { { dbgs() << "intermediate fn:\n" << *OrigLoop->getHeader()->getParent() << "\n"; }; } } while (false) |
| 8122 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType (VerboseDebug)) { { dbgs() << "intermediate fn:\n" << *OrigLoop->getHeader()->getParent() << "\n"; }; } } while (false); |
| 8123 | } |
| 8124 | |
| 8125 | BasicBlock *EpilogueVectorizerMainLoop::emitMinimumIterationCountCheck( |
| 8126 | Loop *L, BasicBlock *Bypass, bool ForEpilogue) { |
| 8127 | assert(L && "Expected valid Loop.")(static_cast <bool> (L && "Expected valid Loop." ) ? void (0) : __assert_fail ("L && \"Expected valid Loop.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8127, __extension__ __PRETTY_FUNCTION__)); |
| 8128 | assert(Bypass && "Expected valid bypass basic block.")(static_cast <bool> (Bypass && "Expected valid bypass basic block." ) ? void (0) : __assert_fail ("Bypass && \"Expected valid bypass basic block.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8128, __extension__ __PRETTY_FUNCTION__)); |
| 8129 | ElementCount VFactor = ForEpilogue ? EPI.EpilogueVF : VF; |
| 8130 | unsigned UFactor = ForEpilogue ? EPI.EpilogueUF : UF; |
| 8131 | Value *Count = getOrCreateTripCount(L); |
| 8132 | // Reuse existing vector loop preheader for TC checks. |
| 8133 | // Note that new preheader block is generated for vector loop. |
| 8134 | BasicBlock *const TCCheckBlock = LoopVectorPreHeader; |
| 8135 | IRBuilder<> Builder(TCCheckBlock->getTerminator()); |
| 8136 | |
| 8137 | // Generate code to check if the loop's trip count is less than VF * UF of the |
| 8138 | // main vector loop. |
| 8139 | auto P = Cost->requiresScalarEpilogue(ForEpilogue ? EPI.EpilogueVF : VF) ? |
| 8140 | ICmpInst::ICMP_ULE : ICmpInst::ICMP_ULT; |
| 8141 | |
| 8142 | Value *CheckMinIters = Builder.CreateICmp( |
| 8143 | P, Count, createStepForVF(Builder, Count->getType(), VFactor, UFactor), |
| 8144 | "min.iters.check"); |
| 8145 | |
| 8146 | if (!ForEpilogue) |
| 8147 | TCCheckBlock->setName("vector.main.loop.iter.check"); |
| 8148 | |
| 8149 | // Create new preheader for vector loop. |
| 8150 | LoopVectorPreHeader = SplitBlock(TCCheckBlock, TCCheckBlock->getTerminator(), |
| 8151 | DT, LI, nullptr, "vector.ph"); |
| 8152 | |
| 8153 | if (ForEpilogue) { |
| 8154 | assert(DT->properlyDominates(DT->getNode(TCCheckBlock),(static_cast <bool> (DT->properlyDominates(DT->getNode (TCCheckBlock), DT->getNode(Bypass)->getIDom()) && "TC check is expected to dominate Bypass") ? void (0) : __assert_fail ("DT->properlyDominates(DT->getNode(TCCheckBlock), DT->getNode(Bypass)->getIDom()) && \"TC check is expected to dominate Bypass\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8156, __extension__ __PRETTY_FUNCTION__)) |
| 8155 | DT->getNode(Bypass)->getIDom()) &&(static_cast <bool> (DT->properlyDominates(DT->getNode (TCCheckBlock), DT->getNode(Bypass)->getIDom()) && "TC check is expected to dominate Bypass") ? void (0) : __assert_fail ("DT->properlyDominates(DT->getNode(TCCheckBlock), DT->getNode(Bypass)->getIDom()) && \"TC check is expected to dominate Bypass\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8156, __extension__ __PRETTY_FUNCTION__)) |
| 8156 | "TC check is expected to dominate Bypass")(static_cast <bool> (DT->properlyDominates(DT->getNode (TCCheckBlock), DT->getNode(Bypass)->getIDom()) && "TC check is expected to dominate Bypass") ? void (0) : __assert_fail ("DT->properlyDominates(DT->getNode(TCCheckBlock), DT->getNode(Bypass)->getIDom()) && \"TC check is expected to dominate Bypass\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8156, __extension__ __PRETTY_FUNCTION__)); |
| 8157 | |
| 8158 | // Update dominator for Bypass & LoopExit. |
| 8159 | DT->changeImmediateDominator(Bypass, TCCheckBlock); |
| 8160 | if (!Cost->requiresScalarEpilogue(EPI.EpilogueVF)) |
| 8161 | // For loops with multiple exits, there's no edge from the middle block |
| 8162 | // to exit blocks (as the epilogue must run) and thus no need to update |
| 8163 | // the immediate dominator of the exit blocks. |
| 8164 | DT->changeImmediateDominator(LoopExitBlock, TCCheckBlock); |
| 8165 | |
| 8166 | LoopBypassBlocks.push_back(TCCheckBlock); |
| 8167 | |
| 8168 | // Save the trip count so we don't have to regenerate it in the |
| 8169 | // vec.epilog.iter.check. This is safe to do because the trip count |
| 8170 | // generated here dominates the vector epilog iter check. |
| 8171 | EPI.TripCount = Count; |
| 8172 | } |
| 8173 | |
| 8174 | ReplaceInstWithInst( |
| 8175 | TCCheckBlock->getTerminator(), |
| 8176 | BranchInst::Create(Bypass, LoopVectorPreHeader, CheckMinIters)); |
| 8177 | |
| 8178 | return TCCheckBlock; |
| 8179 | } |
| 8180 | |
| 8181 | //===--------------------------------------------------------------------===// |
| 8182 | // EpilogueVectorizerEpilogueLoop |
| 8183 | //===--------------------------------------------------------------------===// |
| 8184 | |
| 8185 | /// This function is partially responsible for generating the control flow |
| 8186 | /// depicted in https://llvm.org/docs/Vectorizers.html#epilogue-vectorization. |
| 8187 | std::pair<BasicBlock *, Value *> |
| 8188 | EpilogueVectorizerEpilogueLoop::createEpilogueVectorizedLoopSkeleton() { |
| 8189 | MDNode *OrigLoopID = OrigLoop->getLoopID(); |
| 8190 | Loop *Lp = createVectorLoopSkeleton("vec.epilog."); |
| 8191 | |
| 8192 | // Now, compare the remaining count and if there aren't enough iterations to |
| 8193 | // execute the vectorized epilogue skip to the scalar part. |
| 8194 | BasicBlock *VecEpilogueIterationCountCheck = LoopVectorPreHeader; |
| 8195 | VecEpilogueIterationCountCheck->setName("vec.epilog.iter.check"); |
| 8196 | LoopVectorPreHeader = |
| 8197 | SplitBlock(LoopVectorPreHeader, LoopVectorPreHeader->getTerminator(), DT, |
| 8198 | LI, nullptr, "vec.epilog.ph"); |
| 8199 | emitMinimumVectorEpilogueIterCountCheck(Lp, LoopScalarPreHeader, |
| 8200 | VecEpilogueIterationCountCheck); |
| 8201 | |
| 8202 | // Adjust the control flow taking the state info from the main loop |
| 8203 | // vectorization into account. |
| 8204 | assert(EPI.MainLoopIterationCountCheck && EPI.EpilogueIterationCountCheck &&(static_cast <bool> (EPI.MainLoopIterationCountCheck && EPI.EpilogueIterationCountCheck && "expected this to be saved from the previous pass." ) ? void (0) : __assert_fail ("EPI.MainLoopIterationCountCheck && EPI.EpilogueIterationCountCheck && \"expected this to be saved from the previous pass.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8205, __extension__ __PRETTY_FUNCTION__)) |
| 8205 | "expected this to be saved from the previous pass.")(static_cast <bool> (EPI.MainLoopIterationCountCheck && EPI.EpilogueIterationCountCheck && "expected this to be saved from the previous pass." ) ? void (0) : __assert_fail ("EPI.MainLoopIterationCountCheck && EPI.EpilogueIterationCountCheck && \"expected this to be saved from the previous pass.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8205, __extension__ __PRETTY_FUNCTION__)); |
| 8206 | EPI.MainLoopIterationCountCheck->getTerminator()->replaceUsesOfWith( |
| 8207 | VecEpilogueIterationCountCheck, LoopVectorPreHeader); |
| 8208 | |
| 8209 | DT->changeImmediateDominator(LoopVectorPreHeader, |
| 8210 | EPI.MainLoopIterationCountCheck); |
| 8211 | |
| 8212 | EPI.EpilogueIterationCountCheck->getTerminator()->replaceUsesOfWith( |
| 8213 | VecEpilogueIterationCountCheck, LoopScalarPreHeader); |
| 8214 | |
| 8215 | if (EPI.SCEVSafetyCheck) |
| 8216 | EPI.SCEVSafetyCheck->getTerminator()->replaceUsesOfWith( |
| 8217 | VecEpilogueIterationCountCheck, LoopScalarPreHeader); |
| 8218 | if (EPI.MemSafetyCheck) |
| 8219 | EPI.MemSafetyCheck->getTerminator()->replaceUsesOfWith( |
| 8220 | VecEpilogueIterationCountCheck, LoopScalarPreHeader); |
| 8221 | |
| 8222 | DT->changeImmediateDominator( |
| 8223 | VecEpilogueIterationCountCheck, |
| 8224 | VecEpilogueIterationCountCheck->getSinglePredecessor()); |
| 8225 | |
| 8226 | DT->changeImmediateDominator(LoopScalarPreHeader, |
| 8227 | EPI.EpilogueIterationCountCheck); |
| 8228 | if (!Cost->requiresScalarEpilogue(EPI.EpilogueVF)) |
| 8229 | // If there is an epilogue which must run, there's no edge from the |
| 8230 | // middle block to exit blocks and thus no need to update the immediate |
| 8231 | // dominator of the exit blocks. |
| 8232 | DT->changeImmediateDominator(LoopExitBlock, |
| 8233 | EPI.EpilogueIterationCountCheck); |
| 8234 | |
| 8235 | // Keep track of bypass blocks, as they feed start values to the induction |
| 8236 | // phis in the scalar loop preheader. |
| 8237 | if (EPI.SCEVSafetyCheck) |
| 8238 | LoopBypassBlocks.push_back(EPI.SCEVSafetyCheck); |
| 8239 | if (EPI.MemSafetyCheck) |
| 8240 | LoopBypassBlocks.push_back(EPI.MemSafetyCheck); |
| 8241 | LoopBypassBlocks.push_back(EPI.EpilogueIterationCountCheck); |
| 8242 | |
| 8243 | // The vec.epilog.iter.check block may contain Phi nodes from reductions which |
| 8244 | // merge control-flow from the latch block and the middle block. Update the |
| 8245 | // incoming values here and move the Phi into the preheader. |
| 8246 | SmallVector<PHINode *, 4> PhisInBlock; |
| 8247 | for (PHINode &Phi : VecEpilogueIterationCountCheck->phis()) |
| 8248 | PhisInBlock.push_back(&Phi); |
| 8249 | |
| 8250 | for (PHINode *Phi : PhisInBlock) { |
| 8251 | Phi->replaceIncomingBlockWith( |
| 8252 | VecEpilogueIterationCountCheck->getSinglePredecessor(), |
| 8253 | VecEpilogueIterationCountCheck); |
| 8254 | Phi->removeIncomingValue(EPI.EpilogueIterationCountCheck); |
| 8255 | if (EPI.SCEVSafetyCheck) |
| 8256 | Phi->removeIncomingValue(EPI.SCEVSafetyCheck); |
| 8257 | if (EPI.MemSafetyCheck) |
| 8258 | Phi->removeIncomingValue(EPI.MemSafetyCheck); |
| 8259 | Phi->moveBefore(LoopVectorPreHeader->getFirstNonPHI()); |
| 8260 | } |
| 8261 | |
| 8262 | // Generate a resume induction for the vector epilogue and put it in the |
| 8263 | // vector epilogue preheader |
| 8264 | Type *IdxTy = Legal->getWidestInductionType(); |
| 8265 | PHINode *EPResumeVal = PHINode::Create(IdxTy, 2, "vec.epilog.resume.val", |
| 8266 | LoopVectorPreHeader->getFirstNonPHI()); |
| 8267 | EPResumeVal->addIncoming(EPI.VectorTripCount, VecEpilogueIterationCountCheck); |
| 8268 | EPResumeVal->addIncoming(ConstantInt::get(IdxTy, 0), |
| 8269 | EPI.MainLoopIterationCountCheck); |
| 8270 | |
| 8271 | // Generate the induction variable. |
| 8272 | createHeaderBranch(Lp); |
| 8273 | |
| 8274 | // Generate induction resume values. These variables save the new starting |
| 8275 | // indexes for the scalar loop. They are used to test if there are any tail |
| 8276 | // iterations left once the vector loop has completed. |
| 8277 | // Note that when the vectorized epilogue is skipped due to iteration count |
| 8278 | // check, then the resume value for the induction variable comes from |
| 8279 | // the trip count of the main vector loop, hence passing the AdditionalBypass |
| 8280 | // argument. |
| 8281 | createInductionResumeValues(Lp, {VecEpilogueIterationCountCheck, |
| 8282 | EPI.VectorTripCount} /* AdditionalBypass */); |
| 8283 | |
| 8284 | return {completeLoopSkeleton(Lp, OrigLoopID), EPResumeVal}; |
| 8285 | } |
| 8286 | |
| 8287 | BasicBlock * |
| 8288 | EpilogueVectorizerEpilogueLoop::emitMinimumVectorEpilogueIterCountCheck( |
| 8289 | Loop *L, BasicBlock *Bypass, BasicBlock *Insert) { |
| 8290 | |
| 8291 | assert(EPI.TripCount &&(static_cast <bool> (EPI.TripCount && "Expected trip count to have been safed in the first pass." ) ? void (0) : __assert_fail ("EPI.TripCount && \"Expected trip count to have been safed in the first pass.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8292, __extension__ __PRETTY_FUNCTION__)) |
| 8292 | "Expected trip count to have been safed in the first pass.")(static_cast <bool> (EPI.TripCount && "Expected trip count to have been safed in the first pass." ) ? void (0) : __assert_fail ("EPI.TripCount && \"Expected trip count to have been safed in the first pass.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8292, __extension__ __PRETTY_FUNCTION__)); |
| 8293 | assert((static_cast <bool> ((!isa<Instruction>(EPI.TripCount ) || DT->dominates(cast<Instruction>(EPI.TripCount)-> getParent(), Insert)) && "saved trip count does not dominate insertion point." ) ? void (0) : __assert_fail ("(!isa<Instruction>(EPI.TripCount) || DT->dominates(cast<Instruction>(EPI.TripCount)->getParent(), Insert)) && \"saved trip count does not dominate insertion point.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8296, __extension__ __PRETTY_FUNCTION__)) |
| 8294 | (!isa<Instruction>(EPI.TripCount) ||(static_cast <bool> ((!isa<Instruction>(EPI.TripCount ) || DT->dominates(cast<Instruction>(EPI.TripCount)-> getParent(), Insert)) && "saved trip count does not dominate insertion point." ) ? void (0) : __assert_fail ("(!isa<Instruction>(EPI.TripCount) || DT->dominates(cast<Instruction>(EPI.TripCount)->getParent(), Insert)) && \"saved trip count does not dominate insertion point.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8296, __extension__ __PRETTY_FUNCTION__)) |
| 8295 | DT->dominates(cast<Instruction>(EPI.TripCount)->getParent(), Insert)) &&(static_cast <bool> ((!isa<Instruction>(EPI.TripCount ) || DT->dominates(cast<Instruction>(EPI.TripCount)-> getParent(), Insert)) && "saved trip count does not dominate insertion point." ) ? void (0) : __assert_fail ("(!isa<Instruction>(EPI.TripCount) || DT->dominates(cast<Instruction>(EPI.TripCount)->getParent(), Insert)) && \"saved trip count does not dominate insertion point.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8296, __extension__ __PRETTY_FUNCTION__)) |
| 8296 | "saved trip count does not dominate insertion point.")(static_cast <bool> ((!isa<Instruction>(EPI.TripCount ) || DT->dominates(cast<Instruction>(EPI.TripCount)-> getParent(), Insert)) && "saved trip count does not dominate insertion point." ) ? void (0) : __assert_fail ("(!isa<Instruction>(EPI.TripCount) || DT->dominates(cast<Instruction>(EPI.TripCount)->getParent(), Insert)) && \"saved trip count does not dominate insertion point.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8296, __extension__ __PRETTY_FUNCTION__)); |
| 8297 | Value *TC = EPI.TripCount; |
| 8298 | IRBuilder<> Builder(Insert->getTerminator()); |
| 8299 | Value *Count = Builder.CreateSub(TC, EPI.VectorTripCount, "n.vec.remaining"); |
| 8300 | |
| 8301 | // Generate code to check if the loop's trip count is less than VF * UF of the |
| 8302 | // vector epilogue loop. |
| 8303 | auto P = Cost->requiresScalarEpilogue(EPI.EpilogueVF) ? |
| 8304 | ICmpInst::ICMP_ULE : ICmpInst::ICMP_ULT; |
| 8305 | |
| 8306 | Value *CheckMinIters = |
| 8307 | Builder.CreateICmp(P, Count, |
| 8308 | createStepForVF(Builder, Count->getType(), |
| 8309 | EPI.EpilogueVF, EPI.EpilogueUF), |
| 8310 | "min.epilog.iters.check"); |
| 8311 | |
| 8312 | ReplaceInstWithInst( |
| 8313 | Insert->getTerminator(), |
| 8314 | BranchInst::Create(Bypass, LoopVectorPreHeader, CheckMinIters)); |
| 8315 | |
| 8316 | LoopBypassBlocks.push_back(Insert); |
| 8317 | return Insert; |
| 8318 | } |
| 8319 | |
| 8320 | void EpilogueVectorizerEpilogueLoop::printDebugTracesAtStart() { |
| 8321 | LLVM_DEBUG({do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (second pass)\n" << "Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8322 | dbgs() << "Create Skeleton for epilogue vectorized loop (second pass)\n"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (second pass)\n" << "Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8323 | << "Epilogue Loop VF:" << EPI.EpilogueVFdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (second pass)\n" << "Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8324 | << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (second pass)\n" << "Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false) |
| 8325 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { { dbgs() << "Create Skeleton for epilogue vectorized loop (second pass)\n" << "Epilogue Loop VF:" << EPI.EpilogueVF << ", Epilogue Loop UF:" << EPI.EpilogueUF << "\n"; }; } } while (false); |
| 8326 | } |
| 8327 | |
| 8328 | void EpilogueVectorizerEpilogueLoop::printDebugTracesAtEnd() { |
| 8329 | DEBUG_WITH_TYPE(VerboseDebug, {do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType (VerboseDebug)) { { dbgs() << "final fn:\n" << *OrigLoop ->getHeader()->getParent() << "\n"; }; } } while ( false) |
| 8330 | dbgs() << "final fn:\n" << *OrigLoop->getHeader()->getParent() << "\n";do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType (VerboseDebug)) { { dbgs() << "final fn:\n" << *OrigLoop ->getHeader()->getParent() << "\n"; }; } } while ( false) |
| 8331 | })do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType (VerboseDebug)) { { dbgs() << "final fn:\n" << *OrigLoop ->getHeader()->getParent() << "\n"; }; } } while ( false); |
| 8332 | } |
| 8333 | |
| 8334 | bool LoopVectorizationPlanner::getDecisionAndClampRange( |
| 8335 | const std::function<bool(ElementCount)> &Predicate, VFRange &Range) { |
| 8336 | assert(!Range.isEmpty() && "Trying to test an empty VF range.")(static_cast <bool> (!Range.isEmpty() && "Trying to test an empty VF range." ) ? void (0) : __assert_fail ("!Range.isEmpty() && \"Trying to test an empty VF range.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8336, __extension__ __PRETTY_FUNCTION__)); |
| 8337 | bool PredicateAtRangeStart = Predicate(Range.Start); |
| 8338 | |
| 8339 | for (ElementCount TmpVF = Range.Start * 2; |
| 8340 | ElementCount::isKnownLT(TmpVF, Range.End); TmpVF *= 2) |
| 8341 | if (Predicate(TmpVF) != PredicateAtRangeStart) { |
| 8342 | Range.End = TmpVF; |
| 8343 | break; |
| 8344 | } |
| 8345 | |
| 8346 | return PredicateAtRangeStart; |
| 8347 | } |
| 8348 | |
| 8349 | /// Build VPlans for the full range of feasible VF's = {\p MinVF, 2 * \p MinVF, |
| 8350 | /// 4 * \p MinVF, ..., \p MaxVF} by repeatedly building a VPlan for a sub-range |
| 8351 | /// of VF's starting at a given VF and extending it as much as possible. Each |
| 8352 | /// vectorization decision can potentially shorten this sub-range during |
| 8353 | /// buildVPlan(). |
| 8354 | void LoopVectorizationPlanner::buildVPlans(ElementCount MinVF, |
| 8355 | ElementCount MaxVF) { |
| 8356 | auto MaxVFPlusOne = MaxVF.getWithIncrement(1); |
| 8357 | for (ElementCount VF = MinVF; ElementCount::isKnownLT(VF, MaxVFPlusOne);) { |
| 8358 | VFRange SubRange = {VF, MaxVFPlusOne}; |
| 8359 | VPlans.push_back(buildVPlan(SubRange)); |
| 8360 | VF = SubRange.End; |
| 8361 | } |
| 8362 | } |
| 8363 | |
| 8364 | VPValue *VPRecipeBuilder::createEdgeMask(BasicBlock *Src, BasicBlock *Dst, |
| 8365 | VPlanPtr &Plan) { |
| 8366 | assert(is_contained(predecessors(Dst), Src) && "Invalid edge")(static_cast <bool> (is_contained(predecessors(Dst), Src ) && "Invalid edge") ? void (0) : __assert_fail ("is_contained(predecessors(Dst), Src) && \"Invalid edge\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8366, __extension__ __PRETTY_FUNCTION__)); |
| 8367 | |
| 8368 | // Look for cached value. |
| 8369 | std::pair<BasicBlock *, BasicBlock *> Edge(Src, Dst); |
| 8370 | EdgeMaskCacheTy::iterator ECEntryIt = EdgeMaskCache.find(Edge); |
| 8371 | if (ECEntryIt != EdgeMaskCache.end()) |
| 8372 | return ECEntryIt->second; |
| 8373 | |
| 8374 | VPValue *SrcMask = createBlockInMask(Src, Plan); |
| 8375 | |
| 8376 | // The terminator has to be a branch inst! |
| 8377 | BranchInst *BI = dyn_cast<BranchInst>(Src->getTerminator()); |
| 8378 | assert(BI && "Unexpected terminator found")(static_cast <bool> (BI && "Unexpected terminator found" ) ? void (0) : __assert_fail ("BI && \"Unexpected terminator found\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8378, __extension__ __PRETTY_FUNCTION__)); |
| 8379 | |
| 8380 | if (!BI->isConditional() || BI->getSuccessor(0) == BI->getSuccessor(1)) |
| 8381 | return EdgeMaskCache[Edge] = SrcMask; |
| 8382 | |
| 8383 | // If source is an exiting block, we know the exit edge is dynamically dead |
| 8384 | // in the vector loop, and thus we don't need to restrict the mask. Avoid |
| 8385 | // adding uses of an otherwise potentially dead instruction. |
| 8386 | if (OrigLoop->isLoopExiting(Src)) |
| 8387 | return EdgeMaskCache[Edge] = SrcMask; |
| 8388 | |
| 8389 | VPValue *EdgeMask = Plan->getOrAddVPValue(BI->getCondition()); |
| 8390 | assert(EdgeMask && "No Edge Mask found for condition")(static_cast <bool> (EdgeMask && "No Edge Mask found for condition" ) ? void (0) : __assert_fail ("EdgeMask && \"No Edge Mask found for condition\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8390, __extension__ __PRETTY_FUNCTION__)); |
| 8391 | |
| 8392 | if (BI->getSuccessor(0) != Dst) |
| 8393 | EdgeMask = Builder.createNot(EdgeMask, BI->getDebugLoc()); |
| 8394 | |
| 8395 | if (SrcMask) { // Otherwise block in-mask is all-one, no need to AND. |
| 8396 | // The condition is 'SrcMask && EdgeMask', which is equivalent to |
| 8397 | // 'select i1 SrcMask, i1 EdgeMask, i1 false'. |
| 8398 | // The select version does not introduce new UB if SrcMask is false and |
| 8399 | // EdgeMask is poison. Using 'and' here introduces undefined behavior. |
| 8400 | VPValue *False = Plan->getOrAddVPValue( |
| 8401 | ConstantInt::getFalse(BI->getCondition()->getType())); |
| 8402 | EdgeMask = |
| 8403 | Builder.createSelect(SrcMask, EdgeMask, False, BI->getDebugLoc()); |
| 8404 | } |
| 8405 | |
| 8406 | return EdgeMaskCache[Edge] = EdgeMask; |
| 8407 | } |
| 8408 | |
| 8409 | VPValue *VPRecipeBuilder::createBlockInMask(BasicBlock *BB, VPlanPtr &Plan) { |
| 8410 | assert(OrigLoop->contains(BB) && "Block is not a part of a loop")(static_cast <bool> (OrigLoop->contains(BB) && "Block is not a part of a loop") ? void (0) : __assert_fail ( "OrigLoop->contains(BB) && \"Block is not a part of a loop\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8410, __extension__ __PRETTY_FUNCTION__)); |
| 8411 | |
| 8412 | // Look for cached value. |
| 8413 | BlockMaskCacheTy::iterator BCEntryIt = BlockMaskCache.find(BB); |
| 8414 | if (BCEntryIt != BlockMaskCache.end()) |
| 8415 | return BCEntryIt->second; |
| 8416 | |
| 8417 | // All-one mask is modelled as no-mask following the convention for masked |
| 8418 | // load/store/gather/scatter. Initialize BlockMask to no-mask. |
| 8419 | VPValue *BlockMask = nullptr; |
| 8420 | |
| 8421 | if (OrigLoop->getHeader() == BB) { |
| 8422 | if (!CM.blockNeedsPredicationForAnyReason(BB)) |
| 8423 | return BlockMaskCache[BB] = BlockMask; // Loop incoming mask is all-one. |
| 8424 | |
| 8425 | // Introduce the early-exit compare IV <= BTC to form header block mask. |
| 8426 | // This is used instead of IV < TC because TC may wrap, unlike BTC. Start by |
| 8427 | // constructing the desired canonical IV in the header block as its first |
| 8428 | // non-phi instructions. |
| 8429 | assert(CM.foldTailByMasking() && "must fold the tail")(static_cast <bool> (CM.foldTailByMasking() && "must fold the tail" ) ? void (0) : __assert_fail ("CM.foldTailByMasking() && \"must fold the tail\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8429, __extension__ __PRETTY_FUNCTION__)); |
| 8430 | VPBasicBlock *HeaderVPBB = Plan->getEntry()->getEntryBasicBlock(); |
| 8431 | auto NewInsertionPoint = HeaderVPBB->getFirstNonPhi(); |
| 8432 | auto *IV = new VPWidenCanonicalIVRecipe(Plan->getCanonicalIV()); |
| 8433 | HeaderVPBB->insert(IV, HeaderVPBB->getFirstNonPhi()); |
| 8434 | |
| 8435 | VPBuilder::InsertPointGuard Guard(Builder); |
| 8436 | Builder.setInsertPoint(HeaderVPBB, NewInsertionPoint); |
| 8437 | if (CM.TTI.emitGetActiveLaneMask()) { |
| 8438 | VPValue *TC = Plan->getOrCreateTripCount(); |
| 8439 | BlockMask = Builder.createNaryOp(VPInstruction::ActiveLaneMask, {IV, TC}); |
| 8440 | } else { |
| 8441 | VPValue *BTC = Plan->getOrCreateBackedgeTakenCount(); |
| 8442 | BlockMask = Builder.createNaryOp(VPInstruction::ICmpULE, {IV, BTC}); |
| 8443 | } |
| 8444 | return BlockMaskCache[BB] = BlockMask; |
| 8445 | } |
| 8446 | |
| 8447 | // This is the block mask. We OR all incoming edges. |
| 8448 | for (auto *Predecessor : predecessors(BB)) { |
| 8449 | VPValue *EdgeMask = createEdgeMask(Predecessor, BB, Plan); |
| 8450 | if (!EdgeMask) // Mask of predecessor is all-one so mask of block is too. |
| 8451 | return BlockMaskCache[BB] = EdgeMask; |
| 8452 | |
| 8453 | if (!BlockMask) { // BlockMask has its initialized nullptr value. |
| 8454 | BlockMask = EdgeMask; |
| 8455 | continue; |
| 8456 | } |
| 8457 | |
| 8458 | BlockMask = Builder.createOr(BlockMask, EdgeMask, {}); |
| 8459 | } |
| 8460 | |
| 8461 | return BlockMaskCache[BB] = BlockMask; |
| 8462 | } |
| 8463 | |
| 8464 | VPRecipeBase *VPRecipeBuilder::tryToWidenMemory(Instruction *I, |
| 8465 | ArrayRef<VPValue *> Operands, |
| 8466 | VFRange &Range, |
| 8467 | VPlanPtr &Plan) { |
| 8468 | assert((isa<LoadInst>(I) || isa<StoreInst>(I)) &&(static_cast <bool> ((isa<LoadInst>(I) || isa< StoreInst>(I)) && "Must be called with either a load or store" ) ? void (0) : __assert_fail ("(isa<LoadInst>(I) || isa<StoreInst>(I)) && \"Must be called with either a load or store\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8469, __extension__ __PRETTY_FUNCTION__)) |
| 8469 | "Must be called with either a load or store")(static_cast <bool> ((isa<LoadInst>(I) || isa< StoreInst>(I)) && "Must be called with either a load or store" ) ? void (0) : __assert_fail ("(isa<LoadInst>(I) || isa<StoreInst>(I)) && \"Must be called with either a load or store\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8469, __extension__ __PRETTY_FUNCTION__)); |
| 8470 | |
| 8471 | auto willWiden = [&](ElementCount VF) -> bool { |
| 8472 | if (VF.isScalar()) |
| 8473 | return false; |
| 8474 | LoopVectorizationCostModel::InstWidening Decision = |
| 8475 | CM.getWideningDecision(I, VF); |
| 8476 | assert(Decision != LoopVectorizationCostModel::CM_Unknown &&(static_cast <bool> (Decision != LoopVectorizationCostModel ::CM_Unknown && "CM decision should be taken at this point." ) ? void (0) : __assert_fail ("Decision != LoopVectorizationCostModel::CM_Unknown && \"CM decision should be taken at this point.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8477, __extension__ __PRETTY_FUNCTION__)) |
| 8477 | "CM decision should be taken at this point.")(static_cast <bool> (Decision != LoopVectorizationCostModel ::CM_Unknown && "CM decision should be taken at this point." ) ? void (0) : __assert_fail ("Decision != LoopVectorizationCostModel::CM_Unknown && \"CM decision should be taken at this point.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8477, __extension__ __PRETTY_FUNCTION__)); |
| 8478 | if (Decision == LoopVectorizationCostModel::CM_Interleave) |
| 8479 | return true; |
| 8480 | if (CM.isScalarAfterVectorization(I, VF) || |
| 8481 | CM.isProfitableToScalarize(I, VF)) |
| 8482 | return false; |
| 8483 | return Decision != LoopVectorizationCostModel::CM_Scalarize; |
| 8484 | }; |
| 8485 | |
| 8486 | if (!LoopVectorizationPlanner::getDecisionAndClampRange(willWiden, Range)) |
| 8487 | return nullptr; |
| 8488 | |
| 8489 | VPValue *Mask = nullptr; |
| 8490 | if (Legal->isMaskRequired(I)) |
| 8491 | Mask = createBlockInMask(I->getParent(), Plan); |
| 8492 | |
| 8493 | // Determine if the pointer operand of the access is either consecutive or |
| 8494 | // reverse consecutive. |
| 8495 | LoopVectorizationCostModel::InstWidening Decision = |
| 8496 | CM.getWideningDecision(I, Range.Start); |
| 8497 | bool Reverse = Decision == LoopVectorizationCostModel::CM_Widen_Reverse; |
| 8498 | bool Consecutive = |
| 8499 | Reverse || Decision == LoopVectorizationCostModel::CM_Widen; |
| 8500 | |
| 8501 | if (LoadInst *Load = dyn_cast<LoadInst>(I)) |
| 8502 | return new VPWidenMemoryInstructionRecipe(*Load, Operands[0], Mask, |
| 8503 | Consecutive, Reverse); |
| 8504 | |
| 8505 | StoreInst *Store = cast<StoreInst>(I); |
| 8506 | return new VPWidenMemoryInstructionRecipe(*Store, Operands[1], Operands[0], |
| 8507 | Mask, Consecutive, Reverse); |
| 8508 | } |
| 8509 | |
| 8510 | static VPWidenIntOrFpInductionRecipe * |
| 8511 | createWidenInductionRecipe(PHINode *Phi, Instruction *PhiOrTrunc, |
| 8512 | VPValue *Start, const InductionDescriptor &IndDesc, |
| 8513 | LoopVectorizationCostModel &CM, Loop &OrigLoop, |
| 8514 | VFRange &Range) { |
| 8515 | // Returns true if an instruction \p I should be scalarized instead of |
| 8516 | // vectorized for the chosen vectorization factor. |
| 8517 | auto ShouldScalarizeInstruction = [&CM](Instruction *I, ElementCount VF) { |
| 8518 | return CM.isScalarAfterVectorization(I, VF) || |
| 8519 | CM.isProfitableToScalarize(I, VF); |
| 8520 | }; |
| 8521 | |
| 8522 | bool NeedsScalarIV = LoopVectorizationPlanner::getDecisionAndClampRange( |
| 8523 | [&](ElementCount VF) { |
| 8524 | // Returns true if we should generate a scalar version of \p IV. |
| 8525 | if (ShouldScalarizeInstruction(PhiOrTrunc, VF)) |
| 8526 | return true; |
| 8527 | auto isScalarInst = [&](User *U) -> bool { |
| 8528 | auto *I = cast<Instruction>(U); |
| 8529 | return OrigLoop.contains(I) && ShouldScalarizeInstruction(I, VF); |
| 8530 | }; |
| 8531 | return any_of(PhiOrTrunc->users(), isScalarInst); |
| 8532 | }, |
| 8533 | Range); |
| 8534 | bool NeedsScalarIVOnly = LoopVectorizationPlanner::getDecisionAndClampRange( |
| 8535 | [&](ElementCount VF) { |
| 8536 | return ShouldScalarizeInstruction(PhiOrTrunc, VF); |
| 8537 | }, |
| 8538 | Range); |
| 8539 | assert(IndDesc.getStartValue() ==(static_cast <bool> (IndDesc.getStartValue() == Phi-> getIncomingValueForBlock(OrigLoop.getLoopPreheader())) ? void (0) : __assert_fail ("IndDesc.getStartValue() == Phi->getIncomingValueForBlock(OrigLoop.getLoopPreheader())" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8540, __extension__ __PRETTY_FUNCTION__)) |
| 8540 | Phi->getIncomingValueForBlock(OrigLoop.getLoopPreheader()))(static_cast <bool> (IndDesc.getStartValue() == Phi-> getIncomingValueForBlock(OrigLoop.getLoopPreheader())) ? void (0) : __assert_fail ("IndDesc.getStartValue() == Phi->getIncomingValueForBlock(OrigLoop.getLoopPreheader())" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8540, __extension__ __PRETTY_FUNCTION__)); |
| 8541 | if (auto *TruncI = dyn_cast<TruncInst>(PhiOrTrunc)) { |
| 8542 | return new VPWidenIntOrFpInductionRecipe(Phi, Start, IndDesc, TruncI, |
| 8543 | NeedsScalarIV, !NeedsScalarIVOnly); |
| 8544 | } |
| 8545 | assert(isa<PHINode>(PhiOrTrunc) && "must be a phi node here")(static_cast <bool> (isa<PHINode>(PhiOrTrunc) && "must be a phi node here") ? void (0) : __assert_fail ("isa<PHINode>(PhiOrTrunc) && \"must be a phi node here\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8545, __extension__ __PRETTY_FUNCTION__)); |
| 8546 | return new VPWidenIntOrFpInductionRecipe(Phi, Start, IndDesc, NeedsScalarIV, |
| 8547 | !NeedsScalarIVOnly); |
| 8548 | } |
| 8549 | |
| 8550 | VPWidenIntOrFpInductionRecipe *VPRecipeBuilder::tryToOptimizeInductionPHI( |
| 8551 | PHINode *Phi, ArrayRef<VPValue *> Operands, VFRange &Range) const { |
| 8552 | |
| 8553 | // Check if this is an integer or fp induction. If so, build the recipe that |
| 8554 | // produces its scalar and vector values. |
| 8555 | if (auto *II = Legal->getIntOrFpInductionDescriptor(Phi)) |
| 8556 | return createWidenInductionRecipe(Phi, Phi, Operands[0], *II, CM, *OrigLoop, |
| 8557 | Range); |
| 8558 | |
| 8559 | return nullptr; |
| 8560 | } |
| 8561 | |
| 8562 | VPWidenIntOrFpInductionRecipe *VPRecipeBuilder::tryToOptimizeInductionTruncate( |
| 8563 | TruncInst *I, ArrayRef<VPValue *> Operands, VFRange &Range, |
| 8564 | VPlan &Plan) const { |
| 8565 | // Optimize the special case where the source is a constant integer |
| 8566 | // induction variable. Notice that we can only optimize the 'trunc' case |
| 8567 | // because (a) FP conversions lose precision, (b) sext/zext may wrap, and |
| 8568 | // (c) other casts depend on pointer size. |
| 8569 | |
| 8570 | // Determine whether \p K is a truncation based on an induction variable that |
| 8571 | // can be optimized. |
| 8572 | auto isOptimizableIVTruncate = |
| 8573 | [&](Instruction *K) -> std::function<bool(ElementCount)> { |
| 8574 | return [=](ElementCount VF) -> bool { |
| 8575 | return CM.isOptimizableIVTruncate(K, VF); |
| 8576 | }; |
| 8577 | }; |
| 8578 | |
| 8579 | if (LoopVectorizationPlanner::getDecisionAndClampRange( |
| 8580 | isOptimizableIVTruncate(I), Range)) { |
| 8581 | |
| 8582 | auto *Phi = cast<PHINode>(I->getOperand(0)); |
| 8583 | const InductionDescriptor &II = *Legal->getIntOrFpInductionDescriptor(Phi); |
| 8584 | VPValue *Start = Plan.getOrAddVPValue(II.getStartValue()); |
| 8585 | return createWidenInductionRecipe(Phi, I, Start, II, CM, *OrigLoop, Range); |
| 8586 | } |
| 8587 | return nullptr; |
| 8588 | } |
| 8589 | |
| 8590 | VPRecipeOrVPValueTy VPRecipeBuilder::tryToBlend(PHINode *Phi, |
| 8591 | ArrayRef<VPValue *> Operands, |
| 8592 | VPlanPtr &Plan) { |
| 8593 | // If all incoming values are equal, the incoming VPValue can be used directly |
| 8594 | // instead of creating a new VPBlendRecipe. |
| 8595 | VPValue *FirstIncoming = Operands[0]; |
| 8596 | if (all_of(Operands, [FirstIncoming](const VPValue *Inc) { |
| 8597 | return FirstIncoming == Inc; |
| 8598 | })) { |
| 8599 | return Operands[0]; |
| 8600 | } |
| 8601 | |
| 8602 | // We know that all PHIs in non-header blocks are converted into selects, so |
| 8603 | // we don't have to worry about the insertion order and we can just use the |
| 8604 | // builder. At this point we generate the predication tree. There may be |
| 8605 | // duplications since this is a simple recursive scan, but future |
| 8606 | // optimizations will clean it up. |
| 8607 | SmallVector<VPValue *, 2> OperandsWithMask; |
| 8608 | unsigned NumIncoming = Phi->getNumIncomingValues(); |
| 8609 | |
| 8610 | for (unsigned In = 0; In < NumIncoming; In++) { |
| 8611 | VPValue *EdgeMask = |
| 8612 | createEdgeMask(Phi->getIncomingBlock(In), Phi->getParent(), Plan); |
| 8613 | assert((EdgeMask || NumIncoming == 1) &&(static_cast <bool> ((EdgeMask || NumIncoming == 1) && "Multiple predecessors with one having a full mask") ? void ( 0) : __assert_fail ("(EdgeMask || NumIncoming == 1) && \"Multiple predecessors with one having a full mask\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8614, __extension__ __PRETTY_FUNCTION__)) |
| 8614 | "Multiple predecessors with one having a full mask")(static_cast <bool> ((EdgeMask || NumIncoming == 1) && "Multiple predecessors with one having a full mask") ? void ( 0) : __assert_fail ("(EdgeMask || NumIncoming == 1) && \"Multiple predecessors with one having a full mask\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8614, __extension__ __PRETTY_FUNCTION__)); |
| 8615 | OperandsWithMask.push_back(Operands[In]); |
| 8616 | if (EdgeMask) |
| 8617 | OperandsWithMask.push_back(EdgeMask); |
| 8618 | } |
| 8619 | return toVPRecipeResult(new VPBlendRecipe(Phi, OperandsWithMask)); |
| 8620 | } |
| 8621 | |
| 8622 | VPWidenCallRecipe *VPRecipeBuilder::tryToWidenCall(CallInst *CI, |
| 8623 | ArrayRef<VPValue *> Operands, |
| 8624 | VFRange &Range) const { |
| 8625 | |
| 8626 | bool IsPredicated = LoopVectorizationPlanner::getDecisionAndClampRange( |
| 8627 | [this, CI](ElementCount VF) { |
| 8628 | return CM.isScalarWithPredication(CI, VF); |
| 8629 | }, |
| 8630 | Range); |
| 8631 | |
| 8632 | if (IsPredicated) |
| 8633 | return nullptr; |
| 8634 | |
| 8635 | Intrinsic::ID ID = getVectorIntrinsicIDForCall(CI, TLI); |
| 8636 | if (ID && (ID == Intrinsic::assume || ID == Intrinsic::lifetime_end || |
| 8637 | ID == Intrinsic::lifetime_start || ID == Intrinsic::sideeffect || |
| 8638 | ID == Intrinsic::pseudoprobe || |
| 8639 | ID == Intrinsic::experimental_noalias_scope_decl)) |
| 8640 | return nullptr; |
| 8641 | |
| 8642 | auto willWiden = [&](ElementCount VF) -> bool { |
| 8643 | Intrinsic::ID ID = getVectorIntrinsicIDForCall(CI, TLI); |
| 8644 | // The following case may be scalarized depending on the VF. |
| 8645 | // The flag shows whether we use Intrinsic or a usual Call for vectorized |
| 8646 | // version of the instruction. |
| 8647 | // Is it beneficial to perform intrinsic call compared to lib call? |
| 8648 | bool NeedToScalarize = false; |
| 8649 | InstructionCost CallCost = CM.getVectorCallCost(CI, VF, NeedToScalarize); |
| 8650 | InstructionCost IntrinsicCost = ID ? CM.getVectorIntrinsicCost(CI, VF) : 0; |
| 8651 | bool UseVectorIntrinsic = ID && IntrinsicCost <= CallCost; |
| 8652 | return UseVectorIntrinsic || !NeedToScalarize; |
| 8653 | }; |
| 8654 | |
| 8655 | if (!LoopVectorizationPlanner::getDecisionAndClampRange(willWiden, Range)) |
| 8656 | return nullptr; |
| 8657 | |
| 8658 | ArrayRef<VPValue *> Ops = Operands.take_front(CI->arg_size()); |
| 8659 | return new VPWidenCallRecipe(*CI, make_range(Ops.begin(), Ops.end())); |
| 8660 | } |
| 8661 | |
| 8662 | bool VPRecipeBuilder::shouldWiden(Instruction *I, VFRange &Range) const { |
| 8663 | assert(!isa<BranchInst>(I) && !isa<PHINode>(I) && !isa<LoadInst>(I) &&(static_cast <bool> (!isa<BranchInst>(I) && !isa<PHINode>(I) && !isa<LoadInst>(I) && !isa<StoreInst>(I) && "Instruction should have been handled earlier" ) ? void (0) : __assert_fail ("!isa<BranchInst>(I) && !isa<PHINode>(I) && !isa<LoadInst>(I) && !isa<StoreInst>(I) && \"Instruction should have been handled earlier\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8664, __extension__ __PRETTY_FUNCTION__)) |
| 8664 | !isa<StoreInst>(I) && "Instruction should have been handled earlier")(static_cast <bool> (!isa<BranchInst>(I) && !isa<PHINode>(I) && !isa<LoadInst>(I) && !isa<StoreInst>(I) && "Instruction should have been handled earlier" ) ? void (0) : __assert_fail ("!isa<BranchInst>(I) && !isa<PHINode>(I) && !isa<LoadInst>(I) && !isa<StoreInst>(I) && \"Instruction should have been handled earlier\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8664, __extension__ __PRETTY_FUNCTION__)); |
| 8665 | // Instruction should be widened, unless it is scalar after vectorization, |
| 8666 | // scalarization is profitable or it is predicated. |
| 8667 | auto WillScalarize = [this, I](ElementCount VF) -> bool { |
| 8668 | return CM.isScalarAfterVectorization(I, VF) || |
| 8669 | CM.isProfitableToScalarize(I, VF) || |
| 8670 | CM.isScalarWithPredication(I, VF); |
| 8671 | }; |
| 8672 | return !LoopVectorizationPlanner::getDecisionAndClampRange(WillScalarize, |
| 8673 | Range); |
| 8674 | } |
| 8675 | |
| 8676 | VPWidenRecipe *VPRecipeBuilder::tryToWiden(Instruction *I, |
| 8677 | ArrayRef<VPValue *> Operands) const { |
| 8678 | auto IsVectorizableOpcode = [](unsigned Opcode) { |
| 8679 | switch (Opcode) { |
| 8680 | case Instruction::Add: |
| 8681 | case Instruction::And: |
| 8682 | case Instruction::AShr: |
| 8683 | case Instruction::BitCast: |
| 8684 | case Instruction::FAdd: |
| 8685 | case Instruction::FCmp: |
| 8686 | case Instruction::FDiv: |
| 8687 | case Instruction::FMul: |
| 8688 | case Instruction::FNeg: |
| 8689 | case Instruction::FPExt: |
| 8690 | case Instruction::FPToSI: |
| 8691 | case Instruction::FPToUI: |
| 8692 | case Instruction::FPTrunc: |
| 8693 | case Instruction::FRem: |
| 8694 | case Instruction::FSub: |
| 8695 | case Instruction::ICmp: |
| 8696 | case Instruction::IntToPtr: |
| 8697 | case Instruction::LShr: |
| 8698 | case Instruction::Mul: |
| 8699 | case Instruction::Or: |
| 8700 | case Instruction::PtrToInt: |
| 8701 | case Instruction::SDiv: |
| 8702 | case Instruction::Select: |
| 8703 | case Instruction::SExt: |
| 8704 | case Instruction::Shl: |
| 8705 | case Instruction::SIToFP: |
| 8706 | case Instruction::SRem: |
| 8707 | case Instruction::Sub: |
| 8708 | case Instruction::Trunc: |
| 8709 | case Instruction::UDiv: |
| 8710 | case Instruction::UIToFP: |
| 8711 | case Instruction::URem: |
| 8712 | case Instruction::Xor: |
| 8713 | case Instruction::ZExt: |
| 8714 | return true; |
| 8715 | } |
| 8716 | return false; |
| 8717 | }; |
| 8718 | |
| 8719 | if (!IsVectorizableOpcode(I->getOpcode())) |
| 8720 | return nullptr; |
| 8721 | |
| 8722 | // Success: widen this instruction. |
| 8723 | return new VPWidenRecipe(*I, make_range(Operands.begin(), Operands.end())); |
| 8724 | } |
| 8725 | |
| 8726 | void VPRecipeBuilder::fixHeaderPhis() { |
| 8727 | BasicBlock *OrigLatch = OrigLoop->getLoopLatch(); |
| 8728 | for (VPHeaderPHIRecipe *R : PhisToFix) { |
| 8729 | auto *PN = cast<PHINode>(R->getUnderlyingValue()); |
| 8730 | VPRecipeBase *IncR = |
| 8731 | getRecipe(cast<Instruction>(PN->getIncomingValueForBlock(OrigLatch))); |
| 8732 | R->addOperand(IncR->getVPSingleValue()); |
| 8733 | } |
| 8734 | } |
| 8735 | |
| 8736 | VPBasicBlock *VPRecipeBuilder::handleReplication( |
| 8737 | Instruction *I, VFRange &Range, VPBasicBlock *VPBB, |
| 8738 | VPlanPtr &Plan) { |
| 8739 | bool IsUniform = LoopVectorizationPlanner::getDecisionAndClampRange( |
| 8740 | [&](ElementCount VF) { return CM.isUniformAfterVectorization(I, VF); }, |
| 8741 | Range); |
| 8742 | |
| 8743 | bool IsPredicated = LoopVectorizationPlanner::getDecisionAndClampRange( |
| 8744 | [&](ElementCount VF) { return CM.isPredicatedInst(I, VF, IsUniform); }, |
| 8745 | Range); |
| 8746 | |
| 8747 | // Even if the instruction is not marked as uniform, there are certain |
| 8748 | // intrinsic calls that can be effectively treated as such, so we check for |
| 8749 | // them here. Conservatively, we only do this for scalable vectors, since |
| 8750 | // for fixed-width VFs we can always fall back on full scalarization. |
| 8751 | if (!IsUniform && Range.Start.isScalable() && isa<IntrinsicInst>(I)) { |
| 8752 | switch (cast<IntrinsicInst>(I)->getIntrinsicID()) { |
| 8753 | case Intrinsic::assume: |
| 8754 | case Intrinsic::lifetime_start: |
| 8755 | case Intrinsic::lifetime_end: |
| 8756 | // For scalable vectors if one of the operands is variant then we still |
| 8757 | // want to mark as uniform, which will generate one instruction for just |
| 8758 | // the first lane of the vector. We can't scalarize the call in the same |
| 8759 | // way as for fixed-width vectors because we don't know how many lanes |
| 8760 | // there are. |
| 8761 | // |
| 8762 | // The reasons for doing it this way for scalable vectors are: |
| 8763 | // 1. For the assume intrinsic generating the instruction for the first |
| 8764 | // lane is still be better than not generating any at all. For |
| 8765 | // example, the input may be a splat across all lanes. |
| 8766 | // 2. For the lifetime start/end intrinsics the pointer operand only |
| 8767 | // does anything useful when the input comes from a stack object, |
| 8768 | // which suggests it should always be uniform. For non-stack objects |
| 8769 | // the effect is to poison the object, which still allows us to |
| 8770 | // remove the call. |
| 8771 | IsUniform = true; |
| 8772 | break; |
| 8773 | default: |
| 8774 | break; |
| 8775 | } |
| 8776 | } |
| 8777 | |
| 8778 | auto *Recipe = new VPReplicateRecipe(I, Plan->mapToVPValues(I->operands()), |
| 8779 | IsUniform, IsPredicated); |
| 8780 | setRecipe(I, Recipe); |
| 8781 | Plan->addVPValue(I, Recipe); |
| 8782 | |
| 8783 | // Find if I uses a predicated instruction. If so, it will use its scalar |
| 8784 | // value. Avoid hoisting the insert-element which packs the scalar value into |
| 8785 | // a vector value, as that happens iff all users use the vector value. |
| 8786 | for (VPValue *Op : Recipe->operands()) { |
| 8787 | auto *PredR = dyn_cast_or_null<VPPredInstPHIRecipe>(Op->getDef()); |
| 8788 | if (!PredR) |
| 8789 | continue; |
| 8790 | auto *RepR = |
| 8791 | cast_or_null<VPReplicateRecipe>(PredR->getOperand(0)->getDef()); |
| 8792 | assert(RepR->isPredicated() &&(static_cast <bool> (RepR->isPredicated() && "expected Replicate recipe to be predicated") ? void (0) : __assert_fail ("RepR->isPredicated() && \"expected Replicate recipe to be predicated\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8793, __extension__ __PRETTY_FUNCTION__)) |
| 8793 | "expected Replicate recipe to be predicated")(static_cast <bool> (RepR->isPredicated() && "expected Replicate recipe to be predicated") ? void (0) : __assert_fail ("RepR->isPredicated() && \"expected Replicate recipe to be predicated\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8793, __extension__ __PRETTY_FUNCTION__)); |
| 8794 | RepR->setAlsoPack(false); |
| 8795 | } |
| 8796 | |
| 8797 | // Finalize the recipe for Instr, first if it is not predicated. |
| 8798 | if (!IsPredicated) { |
| 8799 | LLVM_DEBUG(dbgs() << "LV: Scalarizing:" << *I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Scalarizing:" << *I << "\n"; } } while (false); |
| 8800 | VPBB->appendRecipe(Recipe); |
| 8801 | return VPBB; |
| 8802 | } |
| 8803 | LLVM_DEBUG(dbgs() << "LV: Scalarizing and predicating:" << *I << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Scalarizing and predicating:" << *I << "\n"; } } while (false); |
| 8804 | |
| 8805 | VPBlockBase *SingleSucc = VPBB->getSingleSuccessor(); |
| 8806 | assert(SingleSucc && "VPBB must have a single successor when handling "(static_cast <bool> (SingleSucc && "VPBB must have a single successor when handling " "predicated replication.") ? void (0) : __assert_fail ("SingleSucc && \"VPBB must have a single successor when handling \" \"predicated replication.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8807, __extension__ __PRETTY_FUNCTION__)) |
| 8807 | "predicated replication.")(static_cast <bool> (SingleSucc && "VPBB must have a single successor when handling " "predicated replication.") ? void (0) : __assert_fail ("SingleSucc && \"VPBB must have a single successor when handling \" \"predicated replication.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8807, __extension__ __PRETTY_FUNCTION__)); |
| 8808 | VPBlockUtils::disconnectBlocks(VPBB, SingleSucc); |
| 8809 | // Record predicated instructions for above packing optimizations. |
| 8810 | VPBlockBase *Region = createReplicateRegion(I, Recipe, Plan); |
| 8811 | VPBlockUtils::insertBlockAfter(Region, VPBB); |
| 8812 | auto *RegSucc = new VPBasicBlock(); |
| 8813 | VPBlockUtils::insertBlockAfter(RegSucc, Region); |
| 8814 | VPBlockUtils::connectBlocks(RegSucc, SingleSucc); |
| 8815 | return RegSucc; |
| 8816 | } |
| 8817 | |
| 8818 | VPRegionBlock *VPRecipeBuilder::createReplicateRegion(Instruction *Instr, |
| 8819 | VPRecipeBase *PredRecipe, |
| 8820 | VPlanPtr &Plan) { |
| 8821 | // Instructions marked for predication are replicated and placed under an |
| 8822 | // if-then construct to prevent side-effects. |
| 8823 | |
| 8824 | // Generate recipes to compute the block mask for this region. |
| 8825 | VPValue *BlockInMask = createBlockInMask(Instr->getParent(), Plan); |
| 8826 | |
| 8827 | // Build the triangular if-then region. |
| 8828 | std::string RegionName = (Twine("pred.") + Instr->getOpcodeName()).str(); |
| 8829 | assert(Instr->getParent() && "Predicated instruction not in any basic block")(static_cast <bool> (Instr->getParent() && "Predicated instruction not in any basic block" ) ? void (0) : __assert_fail ("Instr->getParent() && \"Predicated instruction not in any basic block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8829, __extension__ __PRETTY_FUNCTION__)); |
| 8830 | auto *BOMRecipe = new VPBranchOnMaskRecipe(BlockInMask); |
| 8831 | auto *Entry = new VPBasicBlock(Twine(RegionName) + ".entry", BOMRecipe); |
| 8832 | auto *PHIRecipe = Instr->getType()->isVoidTy() |
| 8833 | ? nullptr |
| 8834 | : new VPPredInstPHIRecipe(Plan->getOrAddVPValue(Instr)); |
| 8835 | if (PHIRecipe) { |
| 8836 | Plan->removeVPValueFor(Instr); |
| 8837 | Plan->addVPValue(Instr, PHIRecipe); |
| 8838 | } |
| 8839 | auto *Exit = new VPBasicBlock(Twine(RegionName) + ".continue", PHIRecipe); |
| 8840 | auto *Pred = new VPBasicBlock(Twine(RegionName) + ".if", PredRecipe); |
| 8841 | VPRegionBlock *Region = new VPRegionBlock(Entry, Exit, RegionName, true); |
| 8842 | |
| 8843 | // Note: first set Entry as region entry and then connect successors starting |
| 8844 | // from it in order, to propagate the "parent" of each VPBasicBlock. |
| 8845 | VPBlockUtils::insertTwoBlocksAfter(Pred, Exit, BlockInMask, Entry); |
| 8846 | VPBlockUtils::connectBlocks(Pred, Exit); |
| 8847 | |
| 8848 | return Region; |
| 8849 | } |
| 8850 | |
| 8851 | VPRecipeOrVPValueTy |
| 8852 | VPRecipeBuilder::tryToCreateWidenRecipe(Instruction *Instr, |
| 8853 | ArrayRef<VPValue *> Operands, |
| 8854 | VFRange &Range, VPlanPtr &Plan) { |
| 8855 | // First, check for specific widening recipes that deal with calls, memory |
| 8856 | // operations, inductions and Phi nodes. |
| 8857 | if (auto *CI = dyn_cast<CallInst>(Instr)) |
| 8858 | return toVPRecipeResult(tryToWidenCall(CI, Operands, Range)); |
| 8859 | |
| 8860 | if (isa<LoadInst>(Instr) || isa<StoreInst>(Instr)) |
| 8861 | return toVPRecipeResult(tryToWidenMemory(Instr, Operands, Range, Plan)); |
| 8862 | |
| 8863 | VPRecipeBase *Recipe; |
| 8864 | if (auto Phi = dyn_cast<PHINode>(Instr)) { |
| 8865 | if (Phi->getParent() != OrigLoop->getHeader()) |
| 8866 | return tryToBlend(Phi, Operands, Plan); |
| 8867 | if ((Recipe = tryToOptimizeInductionPHI(Phi, Operands, Range))) |
| 8868 | return toVPRecipeResult(Recipe); |
| 8869 | |
| 8870 | VPHeaderPHIRecipe *PhiRecipe = nullptr; |
| 8871 | if (Legal->isReductionVariable(Phi) || Legal->isFirstOrderRecurrence(Phi)) { |
| 8872 | VPValue *StartV = Operands[0]; |
| 8873 | if (Legal->isReductionVariable(Phi)) { |
| 8874 | const RecurrenceDescriptor &RdxDesc = |
| 8875 | Legal->getReductionVars().find(Phi)->second; |
| 8876 | assert(RdxDesc.getRecurrenceStartValue() ==(static_cast <bool> (RdxDesc.getRecurrenceStartValue() == Phi->getIncomingValueForBlock(OrigLoop->getLoopPreheader ())) ? void (0) : __assert_fail ("RdxDesc.getRecurrenceStartValue() == Phi->getIncomingValueForBlock(OrigLoop->getLoopPreheader())" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8877, __extension__ __PRETTY_FUNCTION__)) |
| 8877 | Phi->getIncomingValueForBlock(OrigLoop->getLoopPreheader()))(static_cast <bool> (RdxDesc.getRecurrenceStartValue() == Phi->getIncomingValueForBlock(OrigLoop->getLoopPreheader ())) ? void (0) : __assert_fail ("RdxDesc.getRecurrenceStartValue() == Phi->getIncomingValueForBlock(OrigLoop->getLoopPreheader())" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8877, __extension__ __PRETTY_FUNCTION__)); |
| 8878 | PhiRecipe = new VPReductionPHIRecipe(Phi, RdxDesc, *StartV, |
| 8879 | CM.isInLoopReduction(Phi), |
| 8880 | CM.useOrderedReductions(RdxDesc)); |
| 8881 | } else { |
| 8882 | PhiRecipe = new VPFirstOrderRecurrencePHIRecipe(Phi, *StartV); |
| 8883 | } |
| 8884 | |
| 8885 | // Record the incoming value from the backedge, so we can add the incoming |
| 8886 | // value from the backedge after all recipes have been created. |
| 8887 | recordRecipeOf(cast<Instruction>( |
| 8888 | Phi->getIncomingValueForBlock(OrigLoop->getLoopLatch()))); |
| 8889 | PhisToFix.push_back(PhiRecipe); |
| 8890 | } else { |
| 8891 | // TODO: record backedge value for remaining pointer induction phis. |
| 8892 | assert(Phi->getType()->isPointerTy() &&(static_cast <bool> (Phi->getType()->isPointerTy( ) && "only pointer phis should be handled here") ? void (0) : __assert_fail ("Phi->getType()->isPointerTy() && \"only pointer phis should be handled here\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8893, __extension__ __PRETTY_FUNCTION__)) |
| 8893 | "only pointer phis should be handled here")(static_cast <bool> (Phi->getType()->isPointerTy( ) && "only pointer phis should be handled here") ? void (0) : __assert_fail ("Phi->getType()->isPointerTy() && \"only pointer phis should be handled here\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8893, __extension__ __PRETTY_FUNCTION__)); |
| 8894 | assert(Legal->getInductionVars().count(Phi) &&(static_cast <bool> (Legal->getInductionVars().count (Phi) && "Not an induction variable") ? void (0) : __assert_fail ("Legal->getInductionVars().count(Phi) && \"Not an induction variable\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8895, __extension__ __PRETTY_FUNCTION__)) |
| 8895 | "Not an induction variable")(static_cast <bool> (Legal->getInductionVars().count (Phi) && "Not an induction variable") ? void (0) : __assert_fail ("Legal->getInductionVars().count(Phi) && \"Not an induction variable\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8895, __extension__ __PRETTY_FUNCTION__)); |
| 8896 | InductionDescriptor II = Legal->getInductionVars().lookup(Phi); |
| 8897 | VPValue *Start = Plan->getOrAddVPValue(II.getStartValue()); |
| 8898 | PhiRecipe = new VPWidenPHIRecipe(Phi, Start); |
| 8899 | } |
| 8900 | |
| 8901 | return toVPRecipeResult(PhiRecipe); |
| 8902 | } |
| 8903 | |
| 8904 | if (isa<TruncInst>(Instr) && |
| 8905 | (Recipe = tryToOptimizeInductionTruncate(cast<TruncInst>(Instr), Operands, |
| 8906 | Range, *Plan))) |
| 8907 | return toVPRecipeResult(Recipe); |
| 8908 | |
| 8909 | if (!shouldWiden(Instr, Range)) |
| 8910 | return nullptr; |
| 8911 | |
| 8912 | if (auto GEP = dyn_cast<GetElementPtrInst>(Instr)) |
| 8913 | return toVPRecipeResult(new VPWidenGEPRecipe( |
| 8914 | GEP, make_range(Operands.begin(), Operands.end()), OrigLoop)); |
| 8915 | |
| 8916 | if (auto *SI = dyn_cast<SelectInst>(Instr)) { |
| 8917 | bool InvariantCond = |
| 8918 | PSE.getSE()->isLoopInvariant(PSE.getSCEV(SI->getOperand(0)), OrigLoop); |
| 8919 | return toVPRecipeResult(new VPWidenSelectRecipe( |
| 8920 | *SI, make_range(Operands.begin(), Operands.end()), InvariantCond)); |
| 8921 | } |
| 8922 | |
| 8923 | return toVPRecipeResult(tryToWiden(Instr, Operands)); |
| 8924 | } |
| 8925 | |
| 8926 | void LoopVectorizationPlanner::buildVPlansWithVPRecipes(ElementCount MinVF, |
| 8927 | ElementCount MaxVF) { |
| 8928 | assert(OrigLoop->isInnermost() && "Inner loop expected.")(static_cast <bool> (OrigLoop->isInnermost() && "Inner loop expected.") ? void (0) : __assert_fail ("OrigLoop->isInnermost() && \"Inner loop expected.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8928, __extension__ __PRETTY_FUNCTION__)); |
| 8929 | |
| 8930 | // Collect instructions from the original loop that will become trivially dead |
| 8931 | // in the vectorized loop. We don't need to vectorize these instructions. For |
| 8932 | // example, original induction update instructions can become dead because we |
| 8933 | // separately emit induction "steps" when generating code for the new loop. |
| 8934 | // Similarly, we create a new latch condition when setting up the structure |
| 8935 | // of the new loop, so the old one can become dead. |
| 8936 | SmallPtrSet<Instruction *, 4> DeadInstructions; |
| 8937 | collectTriviallyDeadInstructions(DeadInstructions); |
| 8938 | |
| 8939 | // Add assume instructions we need to drop to DeadInstructions, to prevent |
| 8940 | // them from being added to the VPlan. |
| 8941 | // TODO: We only need to drop assumes in blocks that get flattend. If the |
| 8942 | // control flow is preserved, we should keep them. |
| 8943 | auto &ConditionalAssumes = Legal->getConditionalAssumes(); |
| 8944 | DeadInstructions.insert(ConditionalAssumes.begin(), ConditionalAssumes.end()); |
| 8945 | |
| 8946 | MapVector<Instruction *, Instruction *> &SinkAfter = Legal->getSinkAfter(); |
| 8947 | // Dead instructions do not need sinking. Remove them from SinkAfter. |
| 8948 | for (Instruction *I : DeadInstructions) |
| 8949 | SinkAfter.erase(I); |
| 8950 | |
| 8951 | // Cannot sink instructions after dead instructions (there won't be any |
| 8952 | // recipes for them). Instead, find the first non-dead previous instruction. |
| 8953 | for (auto &P : Legal->getSinkAfter()) { |
| 8954 | Instruction *SinkTarget = P.second; |
| 8955 | Instruction *FirstInst = &*SinkTarget->getParent()->begin(); |
| 8956 | (void)FirstInst; |
| 8957 | while (DeadInstructions.contains(SinkTarget)) { |
| 8958 | assert((static_cast <bool> (SinkTarget != FirstInst && "Must find a live instruction (at least the one feeding the " "first-order recurrence PHI) before reaching beginning of the block" ) ? void (0) : __assert_fail ("SinkTarget != FirstInst && \"Must find a live instruction (at least the one feeding the \" \"first-order recurrence PHI) before reaching beginning of the block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8961, __extension__ __PRETTY_FUNCTION__)) |
| 8959 | SinkTarget != FirstInst &&(static_cast <bool> (SinkTarget != FirstInst && "Must find a live instruction (at least the one feeding the " "first-order recurrence PHI) before reaching beginning of the block" ) ? void (0) : __assert_fail ("SinkTarget != FirstInst && \"Must find a live instruction (at least the one feeding the \" \"first-order recurrence PHI) before reaching beginning of the block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8961, __extension__ __PRETTY_FUNCTION__)) |
| 8960 | "Must find a live instruction (at least the one feeding the "(static_cast <bool> (SinkTarget != FirstInst && "Must find a live instruction (at least the one feeding the " "first-order recurrence PHI) before reaching beginning of the block" ) ? void (0) : __assert_fail ("SinkTarget != FirstInst && \"Must find a live instruction (at least the one feeding the \" \"first-order recurrence PHI) before reaching beginning of the block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8961, __extension__ __PRETTY_FUNCTION__)) |
| 8961 | "first-order recurrence PHI) before reaching beginning of the block")(static_cast <bool> (SinkTarget != FirstInst && "Must find a live instruction (at least the one feeding the " "first-order recurrence PHI) before reaching beginning of the block" ) ? void (0) : __assert_fail ("SinkTarget != FirstInst && \"Must find a live instruction (at least the one feeding the \" \"first-order recurrence PHI) before reaching beginning of the block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8961, __extension__ __PRETTY_FUNCTION__)); |
| 8962 | SinkTarget = SinkTarget->getPrevNode(); |
| 8963 | assert(SinkTarget != P.first &&(static_cast <bool> (SinkTarget != P.first && "sink source equals target, no sinking required" ) ? void (0) : __assert_fail ("SinkTarget != P.first && \"sink source equals target, no sinking required\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8964, __extension__ __PRETTY_FUNCTION__)) |
| 8964 | "sink source equals target, no sinking required")(static_cast <bool> (SinkTarget != P.first && "sink source equals target, no sinking required" ) ? void (0) : __assert_fail ("SinkTarget != P.first && \"sink source equals target, no sinking required\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 8964, __extension__ __PRETTY_FUNCTION__)); |
| 8965 | } |
| 8966 | P.second = SinkTarget; |
| 8967 | } |
| 8968 | |
| 8969 | auto MaxVFPlusOne = MaxVF.getWithIncrement(1); |
| 8970 | for (ElementCount VF = MinVF; ElementCount::isKnownLT(VF, MaxVFPlusOne);) { |
| 8971 | VFRange SubRange = {VF, MaxVFPlusOne}; |
| 8972 | VPlans.push_back( |
| 8973 | buildVPlanWithVPRecipes(SubRange, DeadInstructions, SinkAfter)); |
| 8974 | VF = SubRange.End; |
| 8975 | } |
| 8976 | } |
| 8977 | |
| 8978 | // Add a VPCanonicalIVPHIRecipe starting at 0 to the header, a |
| 8979 | // CanonicalIVIncrement{NUW} VPInstruction to increment it by VF * UF and a |
| 8980 | // BranchOnCount VPInstruction to the latch. |
| 8981 | static void addCanonicalIVRecipes(VPlan &Plan, Type *IdxTy, DebugLoc DL, |
| 8982 | bool HasNUW, bool IsVPlanNative) { |
| 8983 | Value *StartIdx = ConstantInt::get(IdxTy, 0); |
| 8984 | auto *StartV = Plan.getOrAddVPValue(StartIdx); |
| 8985 | |
| 8986 | auto *CanonicalIVPHI = new VPCanonicalIVPHIRecipe(StartV, DL); |
| 8987 | VPRegionBlock *TopRegion = Plan.getVectorLoopRegion(); |
| 8988 | VPBasicBlock *Header = TopRegion->getEntryBasicBlock(); |
| 8989 | if (IsVPlanNative) |
| 8990 | Header = cast<VPBasicBlock>(Header->getSingleSuccessor()); |
| 8991 | Header->insert(CanonicalIVPHI, Header->begin()); |
| 8992 | |
| 8993 | auto *CanonicalIVIncrement = |
| 8994 | new VPInstruction(HasNUW ? VPInstruction::CanonicalIVIncrementNUW |
| 8995 | : VPInstruction::CanonicalIVIncrement, |
| 8996 | {CanonicalIVPHI}, DL); |
| 8997 | CanonicalIVPHI->addOperand(CanonicalIVIncrement); |
| 8998 | |
| 8999 | VPBasicBlock *EB = TopRegion->getExitBasicBlock(); |
| 9000 | if (IsVPlanNative) { |
| 9001 | EB = cast<VPBasicBlock>(EB->getSinglePredecessor()); |
| 9002 | EB->setCondBit(nullptr); |
| 9003 | } |
| 9004 | EB->appendRecipe(CanonicalIVIncrement); |
| 9005 | |
| 9006 | auto *BranchOnCount = |
| 9007 | new VPInstruction(VPInstruction::BranchOnCount, |
| 9008 | {CanonicalIVIncrement, &Plan.getVectorTripCount()}, DL); |
| 9009 | EB->appendRecipe(BranchOnCount); |
| 9010 | } |
| 9011 | |
| 9012 | VPlanPtr LoopVectorizationPlanner::buildVPlanWithVPRecipes( |
| 9013 | VFRange &Range, SmallPtrSetImpl<Instruction *> &DeadInstructions, |
| 9014 | const MapVector<Instruction *, Instruction *> &SinkAfter) { |
| 9015 | |
| 9016 | SmallPtrSet<const InterleaveGroup<Instruction> *, 1> InterleaveGroups; |
| 9017 | |
| 9018 | VPRecipeBuilder RecipeBuilder(OrigLoop, TLI, Legal, CM, PSE, Builder); |
| 9019 | |
| 9020 | // --------------------------------------------------------------------------- |
| 9021 | // Pre-construction: record ingredients whose recipes we'll need to further |
| 9022 | // process after constructing the initial VPlan. |
| 9023 | // --------------------------------------------------------------------------- |
| 9024 | |
| 9025 | // Mark instructions we'll need to sink later and their targets as |
| 9026 | // ingredients whose recipe we'll need to record. |
| 9027 | for (auto &Entry : SinkAfter) { |
| 9028 | RecipeBuilder.recordRecipeOf(Entry.first); |
| 9029 | RecipeBuilder.recordRecipeOf(Entry.second); |
| 9030 | } |
| 9031 | for (auto &Reduction : CM.getInLoopReductionChains()) { |
| 9032 | PHINode *Phi = Reduction.first; |
| 9033 | RecurKind Kind = |
| 9034 | Legal->getReductionVars().find(Phi)->second.getRecurrenceKind(); |
| 9035 | const SmallVector<Instruction *, 4> &ReductionOperations = Reduction.second; |
| 9036 | |
| 9037 | RecipeBuilder.recordRecipeOf(Phi); |
| 9038 | for (auto &R : ReductionOperations) { |
| 9039 | RecipeBuilder.recordRecipeOf(R); |
| 9040 | // For min/max reducitons, where we have a pair of icmp/select, we also |
| 9041 | // need to record the ICmp recipe, so it can be removed later. |
| 9042 | assert(!RecurrenceDescriptor::isSelectCmpRecurrenceKind(Kind) &&(static_cast <bool> (!RecurrenceDescriptor::isSelectCmpRecurrenceKind (Kind) && "Only min/max recurrences allowed for inloop reductions" ) ? void (0) : __assert_fail ("!RecurrenceDescriptor::isSelectCmpRecurrenceKind(Kind) && \"Only min/max recurrences allowed for inloop reductions\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9043, __extension__ __PRETTY_FUNCTION__)) |
| 9043 | "Only min/max recurrences allowed for inloop reductions")(static_cast <bool> (!RecurrenceDescriptor::isSelectCmpRecurrenceKind (Kind) && "Only min/max recurrences allowed for inloop reductions" ) ? void (0) : __assert_fail ("!RecurrenceDescriptor::isSelectCmpRecurrenceKind(Kind) && \"Only min/max recurrences allowed for inloop reductions\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9043, __extension__ __PRETTY_FUNCTION__)); |
| 9044 | if (RecurrenceDescriptor::isMinMaxRecurrenceKind(Kind)) |
| 9045 | RecipeBuilder.recordRecipeOf(cast<Instruction>(R->getOperand(0))); |
| 9046 | } |
| 9047 | } |
| 9048 | |
| 9049 | // For each interleave group which is relevant for this (possibly trimmed) |
| 9050 | // Range, add it to the set of groups to be later applied to the VPlan and add |
| 9051 | // placeholders for its members' Recipes which we'll be replacing with a |
| 9052 | // single VPInterleaveRecipe. |
| 9053 | for (InterleaveGroup<Instruction> *IG : IAI.getInterleaveGroups()) { |
| 9054 | auto applyIG = [IG, this](ElementCount VF) -> bool { |
| 9055 | return (VF.isVector() && // Query is illegal for VF == 1 |
| 9056 | CM.getWideningDecision(IG->getInsertPos(), VF) == |
| 9057 | LoopVectorizationCostModel::CM_Interleave); |
| 9058 | }; |
| 9059 | if (!getDecisionAndClampRange(applyIG, Range)) |
| 9060 | continue; |
| 9061 | InterleaveGroups.insert(IG); |
| 9062 | for (unsigned i = 0; i < IG->getFactor(); i++) |
| 9063 | if (Instruction *Member = IG->getMember(i)) |
| 9064 | RecipeBuilder.recordRecipeOf(Member); |
| 9065 | }; |
| 9066 | |
| 9067 | // --------------------------------------------------------------------------- |
| 9068 | // Build initial VPlan: Scan the body of the loop in a topological order to |
| 9069 | // visit each basic block after having visited its predecessor basic blocks. |
| 9070 | // --------------------------------------------------------------------------- |
| 9071 | |
| 9072 | // Create initial VPlan skeleton, with separate header and latch blocks. |
| 9073 | VPBasicBlock *HeaderVPBB = new VPBasicBlock(); |
| 9074 | VPBasicBlock *LatchVPBB = new VPBasicBlock("vector.latch"); |
| 9075 | VPBlockUtils::insertBlockAfter(LatchVPBB, HeaderVPBB); |
| 9076 | auto *TopRegion = new VPRegionBlock(HeaderVPBB, LatchVPBB, "vector loop"); |
| 9077 | auto Plan = std::make_unique<VPlan>(TopRegion); |
| 9078 | |
| 9079 | Instruction *DLInst = |
| 9080 | getDebugLocFromInstOrOperands(Legal->getPrimaryInduction()); |
| 9081 | addCanonicalIVRecipes(*Plan, Legal->getWidestInductionType(), |
| 9082 | DLInst ? DLInst->getDebugLoc() : DebugLoc(), |
| 9083 | !CM.foldTailByMasking(), false); |
| 9084 | |
| 9085 | // Scan the body of the loop in a topological order to visit each basic block |
| 9086 | // after having visited its predecessor basic blocks. |
| 9087 | LoopBlocksDFS DFS(OrigLoop); |
| 9088 | DFS.perform(LI); |
| 9089 | |
| 9090 | VPBasicBlock *VPBB = HeaderVPBB; |
| 9091 | SmallVector<VPWidenIntOrFpInductionRecipe *> InductionsToMove; |
| 9092 | for (BasicBlock *BB : make_range(DFS.beginRPO(), DFS.endRPO())) { |
| 9093 | // Relevant instructions from basic block BB will be grouped into VPRecipe |
| 9094 | // ingredients and fill a new VPBasicBlock. |
| 9095 | unsigned VPBBsForBB = 0; |
| 9096 | VPBB->setName(BB->getName()); |
| 9097 | Builder.setInsertPoint(VPBB); |
| 9098 | |
| 9099 | // Introduce each ingredient into VPlan. |
| 9100 | // TODO: Model and preserve debug instrinsics in VPlan. |
| 9101 | for (Instruction &I : BB->instructionsWithoutDebug()) { |
| 9102 | Instruction *Instr = &I; |
| 9103 | |
| 9104 | // First filter out irrelevant instructions, to ensure no recipes are |
| 9105 | // built for them. |
| 9106 | if (isa<BranchInst>(Instr) || DeadInstructions.count(Instr)) |
| 9107 | continue; |
| 9108 | |
| 9109 | SmallVector<VPValue *, 4> Operands; |
| 9110 | auto *Phi = dyn_cast<PHINode>(Instr); |
| 9111 | if (Phi && Phi->getParent() == OrigLoop->getHeader()) { |
| 9112 | Operands.push_back(Plan->getOrAddVPValue( |
| 9113 | Phi->getIncomingValueForBlock(OrigLoop->getLoopPreheader()))); |
| 9114 | } else { |
| 9115 | auto OpRange = Plan->mapToVPValues(Instr->operands()); |
| 9116 | Operands = {OpRange.begin(), OpRange.end()}; |
| 9117 | } |
| 9118 | if (auto RecipeOrValue = RecipeBuilder.tryToCreateWidenRecipe( |
| 9119 | Instr, Operands, Range, Plan)) { |
| 9120 | // If Instr can be simplified to an existing VPValue, use it. |
| 9121 | if (RecipeOrValue.is<VPValue *>()) { |
| 9122 | auto *VPV = RecipeOrValue.get<VPValue *>(); |
| 9123 | Plan->addVPValue(Instr, VPV); |
| 9124 | // If the re-used value is a recipe, register the recipe for the |
| 9125 | // instruction, in case the recipe for Instr needs to be recorded. |
| 9126 | if (auto *R = dyn_cast_or_null<VPRecipeBase>(VPV->getDef())) |
| 9127 | RecipeBuilder.setRecipe(Instr, R); |
| 9128 | continue; |
| 9129 | } |
| 9130 | // Otherwise, add the new recipe. |
| 9131 | VPRecipeBase *Recipe = RecipeOrValue.get<VPRecipeBase *>(); |
| 9132 | for (auto *Def : Recipe->definedValues()) { |
| 9133 | auto *UV = Def->getUnderlyingValue(); |
| 9134 | Plan->addVPValue(UV, Def); |
| 9135 | } |
| 9136 | |
| 9137 | if (isa<VPWidenIntOrFpInductionRecipe>(Recipe) && |
| 9138 | HeaderVPBB->getFirstNonPhi() != VPBB->end()) { |
| 9139 | // Keep track of VPWidenIntOrFpInductionRecipes not in the phi section |
| 9140 | // of the header block. That can happen for truncates of induction |
| 9141 | // variables. Those recipes are moved to the phi section of the header |
| 9142 | // block after applying SinkAfter, which relies on the original |
| 9143 | // position of the trunc. |
| 9144 | assert(isa<TruncInst>(Instr))(static_cast <bool> (isa<TruncInst>(Instr)) ? void (0) : __assert_fail ("isa<TruncInst>(Instr)", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 9144, __extension__ __PRETTY_FUNCTION__)); |
| 9145 | InductionsToMove.push_back( |
| 9146 | cast<VPWidenIntOrFpInductionRecipe>(Recipe)); |
| 9147 | } |
| 9148 | RecipeBuilder.setRecipe(Instr, Recipe); |
| 9149 | VPBB->appendRecipe(Recipe); |
| 9150 | continue; |
| 9151 | } |
| 9152 | |
| 9153 | // Otherwise, if all widening options failed, Instruction is to be |
| 9154 | // replicated. This may create a successor for VPBB. |
| 9155 | VPBasicBlock *NextVPBB = |
| 9156 | RecipeBuilder.handleReplication(Instr, Range, VPBB, Plan); |
| 9157 | if (NextVPBB != VPBB) { |
| 9158 | VPBB = NextVPBB; |
| 9159 | VPBB->setName(BB->hasName() ? BB->getName() + "." + Twine(VPBBsForBB++) |
| 9160 | : ""); |
| 9161 | } |
| 9162 | } |
| 9163 | |
| 9164 | VPBlockUtils::insertBlockAfter(new VPBasicBlock(), VPBB); |
| 9165 | VPBB = cast<VPBasicBlock>(VPBB->getSingleSuccessor()); |
| 9166 | } |
| 9167 | |
| 9168 | // Fold the last, empty block into its predecessor. |
| 9169 | VPBB = VPBlockUtils::tryToMergeBlockIntoPredecessor(VPBB); |
| 9170 | assert(VPBB && "expected to fold last (empty) block")(static_cast <bool> (VPBB && "expected to fold last (empty) block" ) ? void (0) : __assert_fail ("VPBB && \"expected to fold last (empty) block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9170, __extension__ __PRETTY_FUNCTION__)); |
| 9171 | // After here, VPBB should not be used. |
| 9172 | VPBB = nullptr; |
| 9173 | |
| 9174 | assert(isa<VPRegionBlock>(Plan->getEntry()) &&(static_cast <bool> (isa<VPRegionBlock>(Plan-> getEntry()) && !Plan->getEntry()->getEntryBasicBlock ()->empty() && "entry block must be set to a VPRegionBlock having a non-empty entry " "VPBasicBlock") ? void (0) : __assert_fail ("isa<VPRegionBlock>(Plan->getEntry()) && !Plan->getEntry()->getEntryBasicBlock()->empty() && \"entry block must be set to a VPRegionBlock having a non-empty entry \" \"VPBasicBlock\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9177, __extension__ __PRETTY_FUNCTION__)) |
| 9175 | !Plan->getEntry()->getEntryBasicBlock()->empty() &&(static_cast <bool> (isa<VPRegionBlock>(Plan-> getEntry()) && !Plan->getEntry()->getEntryBasicBlock ()->empty() && "entry block must be set to a VPRegionBlock having a non-empty entry " "VPBasicBlock") ? void (0) : __assert_fail ("isa<VPRegionBlock>(Plan->getEntry()) && !Plan->getEntry()->getEntryBasicBlock()->empty() && \"entry block must be set to a VPRegionBlock having a non-empty entry \" \"VPBasicBlock\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9177, __extension__ __PRETTY_FUNCTION__)) |
| 9176 | "entry block must be set to a VPRegionBlock having a non-empty entry "(static_cast <bool> (isa<VPRegionBlock>(Plan-> getEntry()) && !Plan->getEntry()->getEntryBasicBlock ()->empty() && "entry block must be set to a VPRegionBlock having a non-empty entry " "VPBasicBlock") ? void (0) : __assert_fail ("isa<VPRegionBlock>(Plan->getEntry()) && !Plan->getEntry()->getEntryBasicBlock()->empty() && \"entry block must be set to a VPRegionBlock having a non-empty entry \" \"VPBasicBlock\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9177, __extension__ __PRETTY_FUNCTION__)) |
| 9177 | "VPBasicBlock")(static_cast <bool> (isa<VPRegionBlock>(Plan-> getEntry()) && !Plan->getEntry()->getEntryBasicBlock ()->empty() && "entry block must be set to a VPRegionBlock having a non-empty entry " "VPBasicBlock") ? void (0) : __assert_fail ("isa<VPRegionBlock>(Plan->getEntry()) && !Plan->getEntry()->getEntryBasicBlock()->empty() && \"entry block must be set to a VPRegionBlock having a non-empty entry \" \"VPBasicBlock\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9177, __extension__ __PRETTY_FUNCTION__)); |
| 9178 | RecipeBuilder.fixHeaderPhis(); |
| 9179 | |
| 9180 | // --------------------------------------------------------------------------- |
| 9181 | // Transform initial VPlan: Apply previously taken decisions, in order, to |
| 9182 | // bring the VPlan to its final state. |
| 9183 | // --------------------------------------------------------------------------- |
| 9184 | |
| 9185 | // Apply Sink-After legal constraints. |
| 9186 | auto GetReplicateRegion = [](VPRecipeBase *R) -> VPRegionBlock * { |
| 9187 | auto *Region = dyn_cast_or_null<VPRegionBlock>(R->getParent()->getParent()); |
| 9188 | if (Region && Region->isReplicator()) { |
| 9189 | assert(Region->getNumSuccessors() == 1 &&(static_cast <bool> (Region->getNumSuccessors() == 1 && Region->getNumPredecessors() == 1 && "Expected SESE region!" ) ? void (0) : __assert_fail ("Region->getNumSuccessors() == 1 && Region->getNumPredecessors() == 1 && \"Expected SESE region!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9190, __extension__ __PRETTY_FUNCTION__)) |
| 9190 | Region->getNumPredecessors() == 1 && "Expected SESE region!")(static_cast <bool> (Region->getNumSuccessors() == 1 && Region->getNumPredecessors() == 1 && "Expected SESE region!" ) ? void (0) : __assert_fail ("Region->getNumSuccessors() == 1 && Region->getNumPredecessors() == 1 && \"Expected SESE region!\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9190, __extension__ __PRETTY_FUNCTION__)); |
| 9191 | assert(R->getParent()->size() == 1 &&(static_cast <bool> (R->getParent()->size() == 1 && "A recipe in an original replicator region must be the only " "recipe in its block") ? void (0) : __assert_fail ("R->getParent()->size() == 1 && \"A recipe in an original replicator region must be the only \" \"recipe in its block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9193, __extension__ __PRETTY_FUNCTION__)) |
| 9192 | "A recipe in an original replicator region must be the only "(static_cast <bool> (R->getParent()->size() == 1 && "A recipe in an original replicator region must be the only " "recipe in its block") ? void (0) : __assert_fail ("R->getParent()->size() == 1 && \"A recipe in an original replicator region must be the only \" \"recipe in its block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9193, __extension__ __PRETTY_FUNCTION__)) |
| 9193 | "recipe in its block")(static_cast <bool> (R->getParent()->size() == 1 && "A recipe in an original replicator region must be the only " "recipe in its block") ? void (0) : __assert_fail ("R->getParent()->size() == 1 && \"A recipe in an original replicator region must be the only \" \"recipe in its block\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9193, __extension__ __PRETTY_FUNCTION__)); |
| 9194 | return Region; |
| 9195 | } |
| 9196 | return nullptr; |
| 9197 | }; |
| 9198 | for (auto &Entry : SinkAfter) { |
| 9199 | VPRecipeBase *Sink = RecipeBuilder.getRecipe(Entry.first); |
| 9200 | VPRecipeBase *Target = RecipeBuilder.getRecipe(Entry.second); |
| 9201 | |
| 9202 | auto *TargetRegion = GetReplicateRegion(Target); |
| 9203 | auto *SinkRegion = GetReplicateRegion(Sink); |
| 9204 | if (!SinkRegion) { |
| 9205 | // If the sink source is not a replicate region, sink the recipe directly. |
| 9206 | if (TargetRegion) { |
| 9207 | // The target is in a replication region, make sure to move Sink to |
| 9208 | // the block after it, not into the replication region itself. |
| 9209 | VPBasicBlock *NextBlock = |
| 9210 | cast<VPBasicBlock>(TargetRegion->getSuccessors().front()); |
| 9211 | Sink->moveBefore(*NextBlock, NextBlock->getFirstNonPhi()); |
| 9212 | } else |
| 9213 | Sink->moveAfter(Target); |
| 9214 | continue; |
| 9215 | } |
| 9216 | |
| 9217 | // The sink source is in a replicate region. Unhook the region from the CFG. |
| 9218 | auto *SinkPred = SinkRegion->getSinglePredecessor(); |
| 9219 | auto *SinkSucc = SinkRegion->getSingleSuccessor(); |
| 9220 | VPBlockUtils::disconnectBlocks(SinkPred, SinkRegion); |
| 9221 | VPBlockUtils::disconnectBlocks(SinkRegion, SinkSucc); |
| 9222 | VPBlockUtils::connectBlocks(SinkPred, SinkSucc); |
| 9223 | |
| 9224 | if (TargetRegion) { |
| 9225 | // The target recipe is also in a replicate region, move the sink region |
| 9226 | // after the target region. |
| 9227 | auto *TargetSucc = TargetRegion->getSingleSuccessor(); |
| 9228 | VPBlockUtils::disconnectBlocks(TargetRegion, TargetSucc); |
| 9229 | VPBlockUtils::connectBlocks(TargetRegion, SinkRegion); |
| 9230 | VPBlockUtils::connectBlocks(SinkRegion, TargetSucc); |
| 9231 | } else { |
| 9232 | // The sink source is in a replicate region, we need to move the whole |
| 9233 | // replicate region, which should only contain a single recipe in the |
| 9234 | // main block. |
| 9235 | auto *SplitBlock = |
| 9236 | Target->getParent()->splitAt(std::next(Target->getIterator())); |
| 9237 | |
| 9238 | auto *SplitPred = SplitBlock->getSinglePredecessor(); |
| 9239 | |
| 9240 | VPBlockUtils::disconnectBlocks(SplitPred, SplitBlock); |
| 9241 | VPBlockUtils::connectBlocks(SplitPred, SinkRegion); |
| 9242 | VPBlockUtils::connectBlocks(SinkRegion, SplitBlock); |
| 9243 | } |
| 9244 | } |
| 9245 | |
| 9246 | VPlanTransforms::removeRedundantCanonicalIVs(*Plan); |
| 9247 | VPlanTransforms::removeRedundantInductionCasts(*Plan); |
| 9248 | |
| 9249 | // Now that sink-after is done, move induction recipes for optimized truncates |
| 9250 | // to the phi section of the header block. |
| 9251 | for (VPWidenIntOrFpInductionRecipe *Ind : InductionsToMove) |
| 9252 | Ind->moveBefore(*HeaderVPBB, HeaderVPBB->getFirstNonPhi()); |
| 9253 | |
| 9254 | // Adjust the recipes for any inloop reductions. |
| 9255 | adjustRecipesForReductions(cast<VPBasicBlock>(TopRegion->getExit()), Plan, |
| 9256 | RecipeBuilder, Range.Start); |
| 9257 | |
| 9258 | // Introduce a recipe to combine the incoming and previous values of a |
| 9259 | // first-order recurrence. |
| 9260 | for (VPRecipeBase &R : Plan->getEntry()->getEntryBasicBlock()->phis()) { |
| 9261 | auto *RecurPhi = dyn_cast<VPFirstOrderRecurrencePHIRecipe>(&R); |
| 9262 | if (!RecurPhi) |
| 9263 | continue; |
| 9264 | |
| 9265 | VPRecipeBase *PrevRecipe = RecurPhi->getBackedgeRecipe(); |
| 9266 | VPBasicBlock *InsertBlock = PrevRecipe->getParent(); |
| 9267 | auto *Region = GetReplicateRegion(PrevRecipe); |
| 9268 | if (Region) |
| 9269 | InsertBlock = cast<VPBasicBlock>(Region->getSingleSuccessor()); |
| 9270 | if (Region || PrevRecipe->isPhi()) |
| 9271 | Builder.setInsertPoint(InsertBlock, InsertBlock->getFirstNonPhi()); |
| 9272 | else |
| 9273 | Builder.setInsertPoint(InsertBlock, std::next(PrevRecipe->getIterator())); |
| 9274 | |
| 9275 | auto *RecurSplice = cast<VPInstruction>( |
| 9276 | Builder.createNaryOp(VPInstruction::FirstOrderRecurrenceSplice, |
| 9277 | {RecurPhi, RecurPhi->getBackedgeValue()})); |
| 9278 | |
| 9279 | RecurPhi->replaceAllUsesWith(RecurSplice); |
| 9280 | // Set the first operand of RecurSplice to RecurPhi again, after replacing |
| 9281 | // all users. |
| 9282 | RecurSplice->setOperand(0, RecurPhi); |
| 9283 | } |
| 9284 | |
| 9285 | // Interleave memory: for each Interleave Group we marked earlier as relevant |
| 9286 | // for this VPlan, replace the Recipes widening its memory instructions with a |
| 9287 | // single VPInterleaveRecipe at its insertion point. |
| 9288 | for (auto IG : InterleaveGroups) { |
| 9289 | auto *Recipe = cast<VPWidenMemoryInstructionRecipe>( |
| 9290 | RecipeBuilder.getRecipe(IG->getInsertPos())); |
| 9291 | SmallVector<VPValue *, 4> StoredValues; |
| 9292 | for (unsigned i = 0; i < IG->getFactor(); ++i) |
| 9293 | if (auto *SI = dyn_cast_or_null<StoreInst>(IG->getMember(i))) { |
| 9294 | auto *StoreR = |
| 9295 | cast<VPWidenMemoryInstructionRecipe>(RecipeBuilder.getRecipe(SI)); |
| 9296 | StoredValues.push_back(StoreR->getStoredValue()); |
| 9297 | } |
| 9298 | |
| 9299 | auto *VPIG = new VPInterleaveRecipe(IG, Recipe->getAddr(), StoredValues, |
| 9300 | Recipe->getMask()); |
| 9301 | VPIG->insertBefore(Recipe); |
| 9302 | unsigned J = 0; |
| 9303 | for (unsigned i = 0; i < IG->getFactor(); ++i) |
| 9304 | if (Instruction *Member = IG->getMember(i)) { |
| 9305 | if (!Member->getType()->isVoidTy()) { |
| 9306 | VPValue *OriginalV = Plan->getVPValue(Member); |
| 9307 | Plan->removeVPValueFor(Member); |
| 9308 | Plan->addVPValue(Member, VPIG->getVPValue(J)); |
| 9309 | OriginalV->replaceAllUsesWith(VPIG->getVPValue(J)); |
| 9310 | J++; |
| 9311 | } |
| 9312 | RecipeBuilder.getRecipe(Member)->eraseFromParent(); |
| 9313 | } |
| 9314 | } |
| 9315 | |
| 9316 | // From this point onwards, VPlan-to-VPlan transformations may change the plan |
| 9317 | // in ways that accessing values using original IR values is incorrect. |
| 9318 | Plan->disableValue2VPValue(); |
| 9319 | |
| 9320 | VPlanTransforms::sinkScalarOperands(*Plan); |
| 9321 | VPlanTransforms::mergeReplicateRegions(*Plan); |
| 9322 | |
| 9323 | std::string PlanName; |
| 9324 | raw_string_ostream RSO(PlanName); |
| 9325 | ElementCount VF = Range.Start; |
| 9326 | Plan->addVF(VF); |
| 9327 | RSO << "Initial VPlan for VF={" << VF; |
| 9328 | for (VF *= 2; ElementCount::isKnownLT(VF, Range.End); VF *= 2) { |
| 9329 | Plan->addVF(VF); |
| 9330 | RSO << "," << VF; |
| 9331 | } |
| 9332 | RSO << "},UF>=1"; |
| 9333 | RSO.flush(); |
| 9334 | Plan->setName(PlanName); |
| 9335 | |
| 9336 | // Fold Exit block into its predecessor if possible. |
| 9337 | // TODO: Fold block earlier once all VPlan transforms properly maintain a |
| 9338 | // VPBasicBlock as exit. |
| 9339 | VPBlockUtils::tryToMergeBlockIntoPredecessor(TopRegion->getExit()); |
| 9340 | |
| 9341 | assert(VPlanVerifier::verifyPlanIsValid(*Plan) && "VPlan is invalid")(static_cast <bool> (VPlanVerifier::verifyPlanIsValid(* Plan) && "VPlan is invalid") ? void (0) : __assert_fail ("VPlanVerifier::verifyPlanIsValid(*Plan) && \"VPlan is invalid\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9341, __extension__ __PRETTY_FUNCTION__)); |
| 9342 | return Plan; |
| 9343 | } |
| 9344 | |
| 9345 | VPlanPtr LoopVectorizationPlanner::buildVPlan(VFRange &Range) { |
| 9346 | // Outer loop handling: They may require CFG and instruction level |
| 9347 | // transformations before even evaluating whether vectorization is profitable. |
| 9348 | // Since we cannot modify the incoming IR, we need to build VPlan upfront in |
| 9349 | // the vectorization pipeline. |
| 9350 | assert(!OrigLoop->isInnermost())(static_cast <bool> (!OrigLoop->isInnermost()) ? void (0) : __assert_fail ("!OrigLoop->isInnermost()", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 9350, __extension__ __PRETTY_FUNCTION__)); |
| 9351 | assert(EnableVPlanNativePath && "VPlan-native path is not enabled.")(static_cast <bool> (EnableVPlanNativePath && "VPlan-native path is not enabled." ) ? void (0) : __assert_fail ("EnableVPlanNativePath && \"VPlan-native path is not enabled.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9351, __extension__ __PRETTY_FUNCTION__)); |
| 9352 | |
| 9353 | // Create new empty VPlan |
| 9354 | auto Plan = std::make_unique<VPlan>(); |
| 9355 | |
| 9356 | // Build hierarchical CFG |
| 9357 | VPlanHCFGBuilder HCFGBuilder(OrigLoop, LI, *Plan); |
| 9358 | HCFGBuilder.buildHierarchicalCFG(); |
| 9359 | |
| 9360 | for (ElementCount VF = Range.Start; ElementCount::isKnownLT(VF, Range.End); |
| 9361 | VF *= 2) |
| 9362 | Plan->addVF(VF); |
| 9363 | |
| 9364 | if (EnableVPlanPredication) { |
| 9365 | VPlanPredicator VPP(*Plan); |
| 9366 | VPP.predicate(); |
| 9367 | |
| 9368 | // Avoid running transformation to recipes until masked code generation in |
| 9369 | // VPlan-native path is in place. |
| 9370 | return Plan; |
| 9371 | } |
| 9372 | |
| 9373 | SmallPtrSet<Instruction *, 1> DeadInstructions; |
| 9374 | VPlanTransforms::VPInstructionsToVPRecipes( |
| 9375 | OrigLoop, Plan, |
| 9376 | [this](PHINode *P) { return Legal->getIntOrFpInductionDescriptor(P); }, |
| 9377 | DeadInstructions, *PSE.getSE()); |
| 9378 | |
| 9379 | addCanonicalIVRecipes(*Plan, Legal->getWidestInductionType(), DebugLoc(), |
| 9380 | true, true); |
| 9381 | return Plan; |
| 9382 | } |
| 9383 | |
| 9384 | // Adjust the recipes for reductions. For in-loop reductions the chain of |
| 9385 | // instructions leading from the loop exit instr to the phi need to be converted |
| 9386 | // to reductions, with one operand being vector and the other being the scalar |
| 9387 | // reduction chain. For other reductions, a select is introduced between the phi |
| 9388 | // and live-out recipes when folding the tail. |
| 9389 | void LoopVectorizationPlanner::adjustRecipesForReductions( |
| 9390 | VPBasicBlock *LatchVPBB, VPlanPtr &Plan, VPRecipeBuilder &RecipeBuilder, |
| 9391 | ElementCount MinVF) { |
| 9392 | for (auto &Reduction : CM.getInLoopReductionChains()) { |
| 9393 | PHINode *Phi = Reduction.first; |
| 9394 | const RecurrenceDescriptor &RdxDesc = |
| 9395 | Legal->getReductionVars().find(Phi)->second; |
| 9396 | const SmallVector<Instruction *, 4> &ReductionOperations = Reduction.second; |
| 9397 | |
| 9398 | if (MinVF.isScalar() && !CM.useOrderedReductions(RdxDesc)) |
| 9399 | continue; |
| 9400 | |
| 9401 | // ReductionOperations are orders top-down from the phi's use to the |
| 9402 | // LoopExitValue. We keep a track of the previous item (the Chain) to tell |
| 9403 | // which of the two operands will remain scalar and which will be reduced. |
| 9404 | // For minmax the chain will be the select instructions. |
| 9405 | Instruction *Chain = Phi; |
| 9406 | for (Instruction *R : ReductionOperations) { |
| 9407 | VPRecipeBase *WidenRecipe = RecipeBuilder.getRecipe(R); |
| 9408 | RecurKind Kind = RdxDesc.getRecurrenceKind(); |
| 9409 | |
| 9410 | VPValue *ChainOp = Plan->getVPValue(Chain); |
| 9411 | unsigned FirstOpId; |
| 9412 | assert(!RecurrenceDescriptor::isSelectCmpRecurrenceKind(Kind) &&(static_cast <bool> (!RecurrenceDescriptor::isSelectCmpRecurrenceKind (Kind) && "Only min/max recurrences allowed for inloop reductions" ) ? void (0) : __assert_fail ("!RecurrenceDescriptor::isSelectCmpRecurrenceKind(Kind) && \"Only min/max recurrences allowed for inloop reductions\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9413, __extension__ __PRETTY_FUNCTION__)) |
| 9413 | "Only min/max recurrences allowed for inloop reductions")(static_cast <bool> (!RecurrenceDescriptor::isSelectCmpRecurrenceKind (Kind) && "Only min/max recurrences allowed for inloop reductions" ) ? void (0) : __assert_fail ("!RecurrenceDescriptor::isSelectCmpRecurrenceKind(Kind) && \"Only min/max recurrences allowed for inloop reductions\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9413, __extension__ __PRETTY_FUNCTION__)); |
| 9414 | // Recognize a call to the llvm.fmuladd intrinsic. |
| 9415 | bool IsFMulAdd = (Kind == RecurKind::FMulAdd); |
| 9416 | assert((!IsFMulAdd || RecurrenceDescriptor::isFMulAddIntrinsic(R)) &&(static_cast <bool> ((!IsFMulAdd || RecurrenceDescriptor ::isFMulAddIntrinsic(R)) && "Expected instruction to be a call to the llvm.fmuladd intrinsic" ) ? void (0) : __assert_fail ("(!IsFMulAdd || RecurrenceDescriptor::isFMulAddIntrinsic(R)) && \"Expected instruction to be a call to the llvm.fmuladd intrinsic\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9417, __extension__ __PRETTY_FUNCTION__)) |
| 9417 | "Expected instruction to be a call to the llvm.fmuladd intrinsic")(static_cast <bool> ((!IsFMulAdd || RecurrenceDescriptor ::isFMulAddIntrinsic(R)) && "Expected instruction to be a call to the llvm.fmuladd intrinsic" ) ? void (0) : __assert_fail ("(!IsFMulAdd || RecurrenceDescriptor::isFMulAddIntrinsic(R)) && \"Expected instruction to be a call to the llvm.fmuladd intrinsic\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9417, __extension__ __PRETTY_FUNCTION__)); |
| 9418 | if (RecurrenceDescriptor::isMinMaxRecurrenceKind(Kind)) { |
| 9419 | assert(isa<VPWidenSelectRecipe>(WidenRecipe) &&(static_cast <bool> (isa<VPWidenSelectRecipe>(WidenRecipe ) && "Expected to replace a VPWidenSelectSC") ? void ( 0) : __assert_fail ("isa<VPWidenSelectRecipe>(WidenRecipe) && \"Expected to replace a VPWidenSelectSC\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9420, __extension__ __PRETTY_FUNCTION__)) |
| 9420 | "Expected to replace a VPWidenSelectSC")(static_cast <bool> (isa<VPWidenSelectRecipe>(WidenRecipe ) && "Expected to replace a VPWidenSelectSC") ? void ( 0) : __assert_fail ("isa<VPWidenSelectRecipe>(WidenRecipe) && \"Expected to replace a VPWidenSelectSC\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9420, __extension__ __PRETTY_FUNCTION__)); |
| 9421 | FirstOpId = 1; |
| 9422 | } else { |
| 9423 | assert((MinVF.isScalar() || isa<VPWidenRecipe>(WidenRecipe) ||(static_cast <bool> ((MinVF.isScalar() || isa<VPWidenRecipe >(WidenRecipe) || (IsFMulAdd && isa<VPWidenCallRecipe >(WidenRecipe))) && "Expected to replace a VPWidenSC" ) ? void (0) : __assert_fail ("(MinVF.isScalar() || isa<VPWidenRecipe>(WidenRecipe) || (IsFMulAdd && isa<VPWidenCallRecipe>(WidenRecipe))) && \"Expected to replace a VPWidenSC\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9425, __extension__ __PRETTY_FUNCTION__)) |
| 9424 | (IsFMulAdd && isa<VPWidenCallRecipe>(WidenRecipe))) &&(static_cast <bool> ((MinVF.isScalar() || isa<VPWidenRecipe >(WidenRecipe) || (IsFMulAdd && isa<VPWidenCallRecipe >(WidenRecipe))) && "Expected to replace a VPWidenSC" ) ? void (0) : __assert_fail ("(MinVF.isScalar() || isa<VPWidenRecipe>(WidenRecipe) || (IsFMulAdd && isa<VPWidenCallRecipe>(WidenRecipe))) && \"Expected to replace a VPWidenSC\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9425, __extension__ __PRETTY_FUNCTION__)) |
| 9425 | "Expected to replace a VPWidenSC")(static_cast <bool> ((MinVF.isScalar() || isa<VPWidenRecipe >(WidenRecipe) || (IsFMulAdd && isa<VPWidenCallRecipe >(WidenRecipe))) && "Expected to replace a VPWidenSC" ) ? void (0) : __assert_fail ("(MinVF.isScalar() || isa<VPWidenRecipe>(WidenRecipe) || (IsFMulAdd && isa<VPWidenCallRecipe>(WidenRecipe))) && \"Expected to replace a VPWidenSC\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9425, __extension__ __PRETTY_FUNCTION__)); |
| 9426 | FirstOpId = 0; |
| 9427 | } |
| 9428 | unsigned VecOpId = |
| 9429 | R->getOperand(FirstOpId) == Chain ? FirstOpId + 1 : FirstOpId; |
| 9430 | VPValue *VecOp = Plan->getVPValue(R->getOperand(VecOpId)); |
| 9431 | |
| 9432 | auto *CondOp = CM.foldTailByMasking() |
| 9433 | ? RecipeBuilder.createBlockInMask(R->getParent(), Plan) |
| 9434 | : nullptr; |
| 9435 | |
| 9436 | if (IsFMulAdd) { |
| 9437 | // If the instruction is a call to the llvm.fmuladd intrinsic then we |
| 9438 | // need to create an fmul recipe to use as the vector operand for the |
| 9439 | // fadd reduction. |
| 9440 | VPInstruction *FMulRecipe = new VPInstruction( |
| 9441 | Instruction::FMul, {VecOp, Plan->getVPValue(R->getOperand(1))}); |
| 9442 | FMulRecipe->setFastMathFlags(R->getFastMathFlags()); |
| 9443 | WidenRecipe->getParent()->insert(FMulRecipe, |
| 9444 | WidenRecipe->getIterator()); |
| 9445 | VecOp = FMulRecipe; |
| 9446 | } |
| 9447 | VPReductionRecipe *RedRecipe = |
| 9448 | new VPReductionRecipe(&RdxDesc, R, ChainOp, VecOp, CondOp, TTI); |
| 9449 | WidenRecipe->getVPSingleValue()->replaceAllUsesWith(RedRecipe); |
| 9450 | Plan->removeVPValueFor(R); |
| 9451 | Plan->addVPValue(R, RedRecipe); |
| 9452 | WidenRecipe->getParent()->insert(RedRecipe, WidenRecipe->getIterator()); |
| 9453 | WidenRecipe->getVPSingleValue()->replaceAllUsesWith(RedRecipe); |
| 9454 | WidenRecipe->eraseFromParent(); |
| 9455 | |
| 9456 | if (RecurrenceDescriptor::isMinMaxRecurrenceKind(Kind)) { |
| 9457 | VPRecipeBase *CompareRecipe = |
| 9458 | RecipeBuilder.getRecipe(cast<Instruction>(R->getOperand(0))); |
| 9459 | assert(isa<VPWidenRecipe>(CompareRecipe) &&(static_cast <bool> (isa<VPWidenRecipe>(CompareRecipe ) && "Expected to replace a VPWidenSC") ? void (0) : __assert_fail ("isa<VPWidenRecipe>(CompareRecipe) && \"Expected to replace a VPWidenSC\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9460, __extension__ __PRETTY_FUNCTION__)) |
| 9460 | "Expected to replace a VPWidenSC")(static_cast <bool> (isa<VPWidenRecipe>(CompareRecipe ) && "Expected to replace a VPWidenSC") ? void (0) : __assert_fail ("isa<VPWidenRecipe>(CompareRecipe) && \"Expected to replace a VPWidenSC\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9460, __extension__ __PRETTY_FUNCTION__)); |
| 9461 | assert(cast<VPWidenRecipe>(CompareRecipe)->getNumUsers() == 0 &&(static_cast <bool> (cast<VPWidenRecipe>(CompareRecipe )->getNumUsers() == 0 && "Expected no remaining users" ) ? void (0) : __assert_fail ("cast<VPWidenRecipe>(CompareRecipe)->getNumUsers() == 0 && \"Expected no remaining users\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9462, __extension__ __PRETTY_FUNCTION__)) |
| 9462 | "Expected no remaining users")(static_cast <bool> (cast<VPWidenRecipe>(CompareRecipe )->getNumUsers() == 0 && "Expected no remaining users" ) ? void (0) : __assert_fail ("cast<VPWidenRecipe>(CompareRecipe)->getNumUsers() == 0 && \"Expected no remaining users\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9462, __extension__ __PRETTY_FUNCTION__)); |
| 9463 | CompareRecipe->eraseFromParent(); |
| 9464 | } |
| 9465 | Chain = R; |
| 9466 | } |
| 9467 | } |
| 9468 | |
| 9469 | // If tail is folded by masking, introduce selects between the phi |
| 9470 | // and the live-out instruction of each reduction, at the beginning of the |
| 9471 | // dedicated latch block. |
| 9472 | if (CM.foldTailByMasking()) { |
| 9473 | Builder.setInsertPoint(LatchVPBB, LatchVPBB->begin()); |
| 9474 | for (VPRecipeBase &R : Plan->getEntry()->getEntryBasicBlock()->phis()) { |
| 9475 | VPReductionPHIRecipe *PhiR = dyn_cast<VPReductionPHIRecipe>(&R); |
| 9476 | if (!PhiR || PhiR->isInLoop()) |
| 9477 | continue; |
| 9478 | VPValue *Cond = |
| 9479 | RecipeBuilder.createBlockInMask(OrigLoop->getHeader(), Plan); |
| 9480 | VPValue *Red = PhiR->getBackedgeValue(); |
| 9481 | assert(cast<VPRecipeBase>(Red->getDef())->getParent() != LatchVPBB &&(static_cast <bool> (cast<VPRecipeBase>(Red->getDef ())->getParent() != LatchVPBB && "reduction recipe must be defined before latch" ) ? void (0) : __assert_fail ("cast<VPRecipeBase>(Red->getDef())->getParent() != LatchVPBB && \"reduction recipe must be defined before latch\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9482, __extension__ __PRETTY_FUNCTION__)) |
| 9482 | "reduction recipe must be defined before latch")(static_cast <bool> (cast<VPRecipeBase>(Red->getDef ())->getParent() != LatchVPBB && "reduction recipe must be defined before latch" ) ? void (0) : __assert_fail ("cast<VPRecipeBase>(Red->getDef())->getParent() != LatchVPBB && \"reduction recipe must be defined before latch\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9482, __extension__ __PRETTY_FUNCTION__)); |
| 9483 | Builder.createNaryOp(Instruction::Select, {Cond, Red, PhiR}); |
| 9484 | } |
| 9485 | } |
| 9486 | } |
| 9487 | |
| 9488 | #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) |
| 9489 | void VPInterleaveRecipe::print(raw_ostream &O, const Twine &Indent, |
| 9490 | VPSlotTracker &SlotTracker) const { |
| 9491 | O << Indent << "INTERLEAVE-GROUP with factor " << IG->getFactor() << " at "; |
| 9492 | IG->getInsertPos()->printAsOperand(O, false); |
| 9493 | O << ", "; |
| 9494 | getAddr()->printAsOperand(O, SlotTracker); |
| 9495 | VPValue *Mask = getMask(); |
| 9496 | if (Mask) { |
| 9497 | O << ", "; |
| 9498 | Mask->printAsOperand(O, SlotTracker); |
| 9499 | } |
| 9500 | |
| 9501 | unsigned OpIdx = 0; |
| 9502 | for (unsigned i = 0; i < IG->getFactor(); ++i) { |
| 9503 | if (!IG->getMember(i)) |
| 9504 | continue; |
| 9505 | if (getNumStoreOperands() > 0) { |
| 9506 | O << "\n" << Indent << " store "; |
| 9507 | getOperand(1 + OpIdx)->printAsOperand(O, SlotTracker); |
| 9508 | O << " to index " << i; |
| 9509 | } else { |
| 9510 | O << "\n" << Indent << " "; |
| 9511 | getVPValue(OpIdx)->printAsOperand(O, SlotTracker); |
| 9512 | O << " = load from index " << i; |
| 9513 | } |
| 9514 | ++OpIdx; |
| 9515 | } |
| 9516 | } |
| 9517 | #endif |
| 9518 | |
| 9519 | void VPWidenCallRecipe::execute(VPTransformState &State) { |
| 9520 | State.ILV->widenCallInstruction(*cast<CallInst>(getUnderlyingInstr()), this, |
| 9521 | *this, State); |
| 9522 | } |
| 9523 | |
| 9524 | void VPWidenSelectRecipe::execute(VPTransformState &State) { |
| 9525 | auto &I = *cast<SelectInst>(getUnderlyingInstr()); |
| 9526 | State.ILV->setDebugLocFromInst(&I); |
| 9527 | |
| 9528 | // The condition can be loop invariant but still defined inside the |
| 9529 | // loop. This means that we can't just use the original 'cond' value. |
| 9530 | // We have to take the 'vectorized' value and pick the first lane. |
| 9531 | // Instcombine will make this a no-op. |
| 9532 | auto *InvarCond = |
| 9533 | InvariantCond ? State.get(getOperand(0), VPIteration(0, 0)) : nullptr; |
| 9534 | |
| 9535 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 9536 | Value *Cond = InvarCond ? InvarCond : State.get(getOperand(0), Part); |
| 9537 | Value *Op0 = State.get(getOperand(1), Part); |
| 9538 | Value *Op1 = State.get(getOperand(2), Part); |
| 9539 | Value *Sel = State.Builder.CreateSelect(Cond, Op0, Op1); |
| 9540 | State.set(this, Sel, Part); |
| 9541 | State.ILV->addMetadata(Sel, &I); |
| 9542 | } |
| 9543 | } |
| 9544 | |
| 9545 | void VPWidenRecipe::execute(VPTransformState &State) { |
| 9546 | auto &I = *cast<Instruction>(getUnderlyingValue()); |
| 9547 | auto &Builder = State.Builder; |
| 9548 | switch (I.getOpcode()) { |
| 9549 | case Instruction::Call: |
| 9550 | case Instruction::Br: |
| 9551 | case Instruction::PHI: |
| 9552 | case Instruction::GetElementPtr: |
| 9553 | case Instruction::Select: |
| 9554 | llvm_unreachable("This instruction is handled by a different recipe.")::llvm::llvm_unreachable_internal("This instruction is handled by a different recipe." , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9554); |
| 9555 | case Instruction::UDiv: |
| 9556 | case Instruction::SDiv: |
| 9557 | case Instruction::SRem: |
| 9558 | case Instruction::URem: |
| 9559 | case Instruction::Add: |
| 9560 | case Instruction::FAdd: |
| 9561 | case Instruction::Sub: |
| 9562 | case Instruction::FSub: |
| 9563 | case Instruction::FNeg: |
| 9564 | case Instruction::Mul: |
| 9565 | case Instruction::FMul: |
| 9566 | case Instruction::FDiv: |
| 9567 | case Instruction::FRem: |
| 9568 | case Instruction::Shl: |
| 9569 | case Instruction::LShr: |
| 9570 | case Instruction::AShr: |
| 9571 | case Instruction::And: |
| 9572 | case Instruction::Or: |
| 9573 | case Instruction::Xor: { |
| 9574 | // Just widen unops and binops. |
| 9575 | State.ILV->setDebugLocFromInst(&I); |
| 9576 | |
| 9577 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 9578 | SmallVector<Value *, 2> Ops; |
| 9579 | for (VPValue *VPOp : operands()) |
| 9580 | Ops.push_back(State.get(VPOp, Part)); |
| 9581 | |
| 9582 | Value *V = Builder.CreateNAryOp(I.getOpcode(), Ops); |
| 9583 | |
| 9584 | if (auto *VecOp = dyn_cast<Instruction>(V)) { |
| 9585 | VecOp->copyIRFlags(&I); |
| 9586 | |
| 9587 | // If the instruction is vectorized and was in a basic block that needed |
| 9588 | // predication, we can't propagate poison-generating flags (nuw/nsw, |
| 9589 | // exact, etc.). The control flow has been linearized and the |
| 9590 | // instruction is no longer guarded by the predicate, which could make |
| 9591 | // the flag properties to no longer hold. |
| 9592 | if (State.MayGeneratePoisonRecipes.contains(this)) |
| 9593 | VecOp->dropPoisonGeneratingFlags(); |
| 9594 | } |
| 9595 | |
| 9596 | // Use this vector value for all users of the original instruction. |
| 9597 | State.set(this, V, Part); |
| 9598 | State.ILV->addMetadata(V, &I); |
| 9599 | } |
| 9600 | |
| 9601 | break; |
| 9602 | } |
| 9603 | case Instruction::ICmp: |
| 9604 | case Instruction::FCmp: { |
| 9605 | // Widen compares. Generate vector compares. |
| 9606 | bool FCmp = (I.getOpcode() == Instruction::FCmp); |
| 9607 | auto *Cmp = cast<CmpInst>(&I); |
| 9608 | State.ILV->setDebugLocFromInst(Cmp); |
| 9609 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 9610 | Value *A = State.get(getOperand(0), Part); |
| 9611 | Value *B = State.get(getOperand(1), Part); |
| 9612 | Value *C = nullptr; |
| 9613 | if (FCmp) { |
| 9614 | // Propagate fast math flags. |
| 9615 | IRBuilder<>::FastMathFlagGuard FMFG(Builder); |
| 9616 | Builder.setFastMathFlags(Cmp->getFastMathFlags()); |
| 9617 | C = Builder.CreateFCmp(Cmp->getPredicate(), A, B); |
| 9618 | } else { |
| 9619 | C = Builder.CreateICmp(Cmp->getPredicate(), A, B); |
| 9620 | } |
| 9621 | State.set(this, C, Part); |
| 9622 | State.ILV->addMetadata(C, &I); |
| 9623 | } |
| 9624 | |
| 9625 | break; |
| 9626 | } |
| 9627 | |
| 9628 | case Instruction::ZExt: |
| 9629 | case Instruction::SExt: |
| 9630 | case Instruction::FPToUI: |
| 9631 | case Instruction::FPToSI: |
| 9632 | case Instruction::FPExt: |
| 9633 | case Instruction::PtrToInt: |
| 9634 | case Instruction::IntToPtr: |
| 9635 | case Instruction::SIToFP: |
| 9636 | case Instruction::UIToFP: |
| 9637 | case Instruction::Trunc: |
| 9638 | case Instruction::FPTrunc: |
| 9639 | case Instruction::BitCast: { |
| 9640 | auto *CI = cast<CastInst>(&I); |
| 9641 | State.ILV->setDebugLocFromInst(CI); |
| 9642 | |
| 9643 | /// Vectorize casts. |
| 9644 | Type *DestTy = (State.VF.isScalar()) |
| 9645 | ? CI->getType() |
| 9646 | : VectorType::get(CI->getType(), State.VF); |
| 9647 | |
| 9648 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 9649 | Value *A = State.get(getOperand(0), Part); |
| 9650 | Value *Cast = Builder.CreateCast(CI->getOpcode(), A, DestTy); |
| 9651 | State.set(this, Cast, Part); |
| 9652 | State.ILV->addMetadata(Cast, &I); |
| 9653 | } |
| 9654 | break; |
| 9655 | } |
| 9656 | default: |
| 9657 | // This instruction is not vectorized by simple widening. |
| 9658 | LLVM_DEBUG(dbgs() << "LV: Found an unhandled instruction: " << I)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found an unhandled instruction: " << I; } } while (false); |
| 9659 | llvm_unreachable("Unhandled instruction!")::llvm::llvm_unreachable_internal("Unhandled instruction!", "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp" , 9659); |
| 9660 | } // end of switch. |
| 9661 | } |
| 9662 | |
| 9663 | void VPWidenGEPRecipe::execute(VPTransformState &State) { |
| 9664 | auto *GEP = cast<GetElementPtrInst>(getUnderlyingInstr()); |
| 9665 | // Construct a vector GEP by widening the operands of the scalar GEP as |
| 9666 | // necessary. We mark the vector GEP 'inbounds' if appropriate. A GEP |
| 9667 | // results in a vector of pointers when at least one operand of the GEP |
| 9668 | // is vector-typed. Thus, to keep the representation compact, we only use |
| 9669 | // vector-typed operands for loop-varying values. |
| 9670 | |
| 9671 | if (State.VF.isVector() && IsPtrLoopInvariant && IsIndexLoopInvariant.all()) { |
| 9672 | // If we are vectorizing, but the GEP has only loop-invariant operands, |
| 9673 | // the GEP we build (by only using vector-typed operands for |
| 9674 | // loop-varying values) would be a scalar pointer. Thus, to ensure we |
| 9675 | // produce a vector of pointers, we need to either arbitrarily pick an |
| 9676 | // operand to broadcast, or broadcast a clone of the original GEP. |
| 9677 | // Here, we broadcast a clone of the original. |
| 9678 | // |
| 9679 | // TODO: If at some point we decide to scalarize instructions having |
| 9680 | // loop-invariant operands, this special case will no longer be |
| 9681 | // required. We would add the scalarization decision to |
| 9682 | // collectLoopScalars() and teach getVectorValue() to broadcast |
| 9683 | // the lane-zero scalar value. |
| 9684 | auto *Clone = State.Builder.Insert(GEP->clone()); |
| 9685 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 9686 | Value *EntryPart = State.Builder.CreateVectorSplat(State.VF, Clone); |
| 9687 | State.set(this, EntryPart, Part); |
| 9688 | State.ILV->addMetadata(EntryPart, GEP); |
| 9689 | } |
| 9690 | } else { |
| 9691 | // If the GEP has at least one loop-varying operand, we are sure to |
| 9692 | // produce a vector of pointers. But if we are only unrolling, we want |
| 9693 | // to produce a scalar GEP for each unroll part. Thus, the GEP we |
| 9694 | // produce with the code below will be scalar (if VF == 1) or vector |
| 9695 | // (otherwise). Note that for the unroll-only case, we still maintain |
| 9696 | // values in the vector mapping with initVector, as we do for other |
| 9697 | // instructions. |
| 9698 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 9699 | // The pointer operand of the new GEP. If it's loop-invariant, we |
| 9700 | // won't broadcast it. |
| 9701 | auto *Ptr = IsPtrLoopInvariant |
| 9702 | ? State.get(getOperand(0), VPIteration(0, 0)) |
| 9703 | : State.get(getOperand(0), Part); |
| 9704 | |
| 9705 | // Collect all the indices for the new GEP. If any index is |
| 9706 | // loop-invariant, we won't broadcast it. |
| 9707 | SmallVector<Value *, 4> Indices; |
| 9708 | for (unsigned I = 1, E = getNumOperands(); I < E; I++) { |
| 9709 | VPValue *Operand = getOperand(I); |
| 9710 | if (IsIndexLoopInvariant[I - 1]) |
| 9711 | Indices.push_back(State.get(Operand, VPIteration(0, 0))); |
| 9712 | else |
| 9713 | Indices.push_back(State.get(Operand, Part)); |
| 9714 | } |
| 9715 | |
| 9716 | // If the GEP instruction is vectorized and was in a basic block that |
| 9717 | // needed predication, we can't propagate the poison-generating 'inbounds' |
| 9718 | // flag. The control flow has been linearized and the GEP is no longer |
| 9719 | // guarded by the predicate, which could make the 'inbounds' properties to |
| 9720 | // no longer hold. |
| 9721 | bool IsInBounds = |
| 9722 | GEP->isInBounds() && State.MayGeneratePoisonRecipes.count(this) == 0; |
| 9723 | |
| 9724 | // Create the new GEP. Note that this GEP may be a scalar if VF == 1, |
| 9725 | // but it should be a vector, otherwise. |
| 9726 | auto *NewGEP = IsInBounds |
| 9727 | ? State.Builder.CreateInBoundsGEP( |
| 9728 | GEP->getSourceElementType(), Ptr, Indices) |
| 9729 | : State.Builder.CreateGEP(GEP->getSourceElementType(), |
| 9730 | Ptr, Indices); |
| 9731 | assert((State.VF.isScalar() || NewGEP->getType()->isVectorTy()) &&(static_cast <bool> ((State.VF.isScalar() || NewGEP-> getType()->isVectorTy()) && "NewGEP is not a pointer vector" ) ? void (0) : __assert_fail ("(State.VF.isScalar() || NewGEP->getType()->isVectorTy()) && \"NewGEP is not a pointer vector\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9732, __extension__ __PRETTY_FUNCTION__)) |
| 9732 | "NewGEP is not a pointer vector")(static_cast <bool> ((State.VF.isScalar() || NewGEP-> getType()->isVectorTy()) && "NewGEP is not a pointer vector" ) ? void (0) : __assert_fail ("(State.VF.isScalar() || NewGEP->getType()->isVectorTy()) && \"NewGEP is not a pointer vector\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9732, __extension__ __PRETTY_FUNCTION__)); |
| 9733 | State.set(this, NewGEP, Part); |
| 9734 | State.ILV->addMetadata(NewGEP, GEP); |
| 9735 | } |
| 9736 | } |
| 9737 | } |
| 9738 | |
| 9739 | void VPWidenIntOrFpInductionRecipe::execute(VPTransformState &State) { |
| 9740 | assert(!State.Instance && "Int or FP induction being replicated.")(static_cast <bool> (!State.Instance && "Int or FP induction being replicated." ) ? void (0) : __assert_fail ("!State.Instance && \"Int or FP induction being replicated.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9740, __extension__ __PRETTY_FUNCTION__)); |
| 9741 | auto *CanonicalIV = State.get(getParent()->getPlan()->getCanonicalIV(), 0); |
| 9742 | State.ILV->widenIntOrFpInduction(IV, this, State, CanonicalIV); |
| 9743 | } |
| 9744 | |
| 9745 | void VPWidenPHIRecipe::execute(VPTransformState &State) { |
| 9746 | State.ILV->widenPHIInstruction(cast<PHINode>(getUnderlyingValue()), this, |
| 9747 | State); |
| 9748 | } |
| 9749 | |
| 9750 | void VPBlendRecipe::execute(VPTransformState &State) { |
| 9751 | State.ILV->setDebugLocFromInst(Phi, &State.Builder); |
| 9752 | // We know that all PHIs in non-header blocks are converted into |
| 9753 | // selects, so we don't have to worry about the insertion order and we |
| 9754 | // can just use the builder. |
| 9755 | // At this point we generate the predication tree. There may be |
| 9756 | // duplications since this is a simple recursive scan, but future |
| 9757 | // optimizations will clean it up. |
| 9758 | |
| 9759 | unsigned NumIncoming = getNumIncomingValues(); |
| 9760 | |
| 9761 | // Generate a sequence of selects of the form: |
| 9762 | // SELECT(Mask3, In3, |
| 9763 | // SELECT(Mask2, In2, |
| 9764 | // SELECT(Mask1, In1, |
| 9765 | // In0))) |
| 9766 | // Note that Mask0 is never used: lanes for which no path reaches this phi and |
| 9767 | // are essentially undef are taken from In0. |
| 9768 | InnerLoopVectorizer::VectorParts Entry(State.UF); |
| 9769 | for (unsigned In = 0; In < NumIncoming; ++In) { |
| 9770 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 9771 | // We might have single edge PHIs (blocks) - use an identity |
| 9772 | // 'select' for the first PHI operand. |
| 9773 | Value *In0 = State.get(getIncomingValue(In), Part); |
| 9774 | if (In == 0) |
| 9775 | Entry[Part] = In0; // Initialize with the first incoming value. |
| 9776 | else { |
| 9777 | // Select between the current value and the previous incoming edge |
| 9778 | // based on the incoming mask. |
| 9779 | Value *Cond = State.get(getMask(In), Part); |
| 9780 | Entry[Part] = |
| 9781 | State.Builder.CreateSelect(Cond, In0, Entry[Part], "predphi"); |
| 9782 | } |
| 9783 | } |
| 9784 | } |
| 9785 | for (unsigned Part = 0; Part < State.UF; ++Part) |
| 9786 | State.set(this, Entry[Part], Part); |
| 9787 | } |
| 9788 | |
| 9789 | void VPInterleaveRecipe::execute(VPTransformState &State) { |
| 9790 | assert(!State.Instance && "Interleave group being replicated.")(static_cast <bool> (!State.Instance && "Interleave group being replicated." ) ? void (0) : __assert_fail ("!State.Instance && \"Interleave group being replicated.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9790, __extension__ __PRETTY_FUNCTION__)); |
| 9791 | State.ILV->vectorizeInterleaveGroup(IG, definedValues(), State, getAddr(), |
| 9792 | getStoredValues(), getMask()); |
| 9793 | } |
| 9794 | |
| 9795 | void VPReductionRecipe::execute(VPTransformState &State) { |
| 9796 | assert(!State.Instance && "Reduction being replicated.")(static_cast <bool> (!State.Instance && "Reduction being replicated." ) ? void (0) : __assert_fail ("!State.Instance && \"Reduction being replicated.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9796, __extension__ __PRETTY_FUNCTION__)); |
| 9797 | Value *PrevInChain = State.get(getChainOp(), 0); |
| 9798 | RecurKind Kind = RdxDesc->getRecurrenceKind(); |
| 9799 | bool IsOrdered = State.ILV->useOrderedReductions(*RdxDesc); |
| 9800 | // Propagate the fast-math flags carried by the underlying instruction. |
| 9801 | IRBuilderBase::FastMathFlagGuard FMFGuard(State.Builder); |
| 9802 | State.Builder.setFastMathFlags(RdxDesc->getFastMathFlags()); |
| 9803 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 9804 | Value *NewVecOp = State.get(getVecOp(), Part); |
| 9805 | if (VPValue *Cond = getCondOp()) { |
| 9806 | Value *NewCond = State.get(Cond, Part); |
| 9807 | VectorType *VecTy = cast<VectorType>(NewVecOp->getType()); |
| 9808 | Value *Iden = RdxDesc->getRecurrenceIdentity( |
| 9809 | Kind, VecTy->getElementType(), RdxDesc->getFastMathFlags()); |
| 9810 | Value *IdenVec = |
| 9811 | State.Builder.CreateVectorSplat(VecTy->getElementCount(), Iden); |
| 9812 | Value *Select = State.Builder.CreateSelect(NewCond, NewVecOp, IdenVec); |
| 9813 | NewVecOp = Select; |
| 9814 | } |
| 9815 | Value *NewRed; |
| 9816 | Value *NextInChain; |
| 9817 | if (IsOrdered) { |
| 9818 | if (State.VF.isVector()) |
| 9819 | NewRed = createOrderedReduction(State.Builder, *RdxDesc, NewVecOp, |
| 9820 | PrevInChain); |
| 9821 | else |
| 9822 | NewRed = State.Builder.CreateBinOp( |
| 9823 | (Instruction::BinaryOps)RdxDesc->getOpcode(Kind), PrevInChain, |
| 9824 | NewVecOp); |
| 9825 | PrevInChain = NewRed; |
| 9826 | } else { |
| 9827 | PrevInChain = State.get(getChainOp(), Part); |
| 9828 | NewRed = createTargetReduction(State.Builder, TTI, *RdxDesc, NewVecOp); |
| 9829 | } |
| 9830 | if (RecurrenceDescriptor::isMinMaxRecurrenceKind(Kind)) { |
| 9831 | NextInChain = |
| 9832 | createMinMaxOp(State.Builder, RdxDesc->getRecurrenceKind(), |
| 9833 | NewRed, PrevInChain); |
| 9834 | } else if (IsOrdered) |
| 9835 | NextInChain = NewRed; |
| 9836 | else |
| 9837 | NextInChain = State.Builder.CreateBinOp( |
| 9838 | (Instruction::BinaryOps)RdxDesc->getOpcode(Kind), NewRed, |
| 9839 | PrevInChain); |
| 9840 | State.set(this, NextInChain, Part); |
| 9841 | } |
| 9842 | } |
| 9843 | |
| 9844 | void VPReplicateRecipe::execute(VPTransformState &State) { |
| 9845 | if (State.Instance) { // Generate a single instance. |
| 9846 | assert(!State.VF.isScalable() && "Can't scalarize a scalable vector")(static_cast <bool> (!State.VF.isScalable() && "Can't scalarize a scalable vector" ) ? void (0) : __assert_fail ("!State.VF.isScalable() && \"Can't scalarize a scalable vector\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9846, __extension__ __PRETTY_FUNCTION__)); |
| 9847 | State.ILV->scalarizeInstruction(getUnderlyingInstr(), this, *State.Instance, |
| 9848 | IsPredicated, State); |
| 9849 | // Insert scalar instance packing it into a vector. |
| 9850 | if (AlsoPack && State.VF.isVector()) { |
| 9851 | // If we're constructing lane 0, initialize to start from poison. |
| 9852 | if (State.Instance->Lane.isFirstLane()) { |
| 9853 | assert(!State.VF.isScalable() && "VF is assumed to be non scalable.")(static_cast <bool> (!State.VF.isScalable() && "VF is assumed to be non scalable." ) ? void (0) : __assert_fail ("!State.VF.isScalable() && \"VF is assumed to be non scalable.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9853, __extension__ __PRETTY_FUNCTION__)); |
| 9854 | Value *Poison = PoisonValue::get( |
| 9855 | VectorType::get(getUnderlyingValue()->getType(), State.VF)); |
| 9856 | State.set(this, Poison, State.Instance->Part); |
| 9857 | } |
| 9858 | State.ILV->packScalarIntoVectorValue(this, *State.Instance, State); |
| 9859 | } |
| 9860 | return; |
| 9861 | } |
| 9862 | |
| 9863 | // Generate scalar instances for all VF lanes of all UF parts, unless the |
| 9864 | // instruction is uniform inwhich case generate only the first lane for each |
| 9865 | // of the UF parts. |
| 9866 | unsigned EndLane = IsUniform ? 1 : State.VF.getKnownMinValue(); |
| 9867 | assert((!State.VF.isScalable() || IsUniform) &&(static_cast <bool> ((!State.VF.isScalable() || IsUniform ) && "Can't scalarize a scalable vector") ? void (0) : __assert_fail ("(!State.VF.isScalable() || IsUniform) && \"Can't scalarize a scalable vector\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9868, __extension__ __PRETTY_FUNCTION__)) |
| 9868 | "Can't scalarize a scalable vector")(static_cast <bool> ((!State.VF.isScalable() || IsUniform ) && "Can't scalarize a scalable vector") ? void (0) : __assert_fail ("(!State.VF.isScalable() || IsUniform) && \"Can't scalarize a scalable vector\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9868, __extension__ __PRETTY_FUNCTION__)); |
| 9869 | for (unsigned Part = 0; Part < State.UF; ++Part) |
| 9870 | for (unsigned Lane = 0; Lane < EndLane; ++Lane) |
| 9871 | State.ILV->scalarizeInstruction(getUnderlyingInstr(), this, |
| 9872 | VPIteration(Part, Lane), IsPredicated, |
| 9873 | State); |
| 9874 | } |
| 9875 | |
| 9876 | void VPBranchOnMaskRecipe::execute(VPTransformState &State) { |
| 9877 | assert(State.Instance && "Branch on Mask works only on single instance.")(static_cast <bool> (State.Instance && "Branch on Mask works only on single instance." ) ? void (0) : __assert_fail ("State.Instance && \"Branch on Mask works only on single instance.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9877, __extension__ __PRETTY_FUNCTION__)); |
| 9878 | |
| 9879 | unsigned Part = State.Instance->Part; |
| 9880 | unsigned Lane = State.Instance->Lane.getKnownLane(); |
| 9881 | |
| 9882 | Value *ConditionBit = nullptr; |
| 9883 | VPValue *BlockInMask = getMask(); |
| 9884 | if (BlockInMask) { |
| 9885 | ConditionBit = State.get(BlockInMask, Part); |
| 9886 | if (ConditionBit->getType()->isVectorTy()) |
| 9887 | ConditionBit = State.Builder.CreateExtractElement( |
| 9888 | ConditionBit, State.Builder.getInt32(Lane)); |
| 9889 | } else // Block in mask is all-one. |
| 9890 | ConditionBit = State.Builder.getTrue(); |
| 9891 | |
| 9892 | // Replace the temporary unreachable terminator with a new conditional branch, |
| 9893 | // whose two destinations will be set later when they are created. |
| 9894 | auto *CurrentTerminator = State.CFG.PrevBB->getTerminator(); |
| 9895 | assert(isa<UnreachableInst>(CurrentTerminator) &&(static_cast <bool> (isa<UnreachableInst>(CurrentTerminator ) && "Expected to replace unreachable terminator with conditional branch." ) ? void (0) : __assert_fail ("isa<UnreachableInst>(CurrentTerminator) && \"Expected to replace unreachable terminator with conditional branch.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9896, __extension__ __PRETTY_FUNCTION__)) |
| 9896 | "Expected to replace unreachable terminator with conditional branch.")(static_cast <bool> (isa<UnreachableInst>(CurrentTerminator ) && "Expected to replace unreachable terminator with conditional branch." ) ? void (0) : __assert_fail ("isa<UnreachableInst>(CurrentTerminator) && \"Expected to replace unreachable terminator with conditional branch.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9896, __extension__ __PRETTY_FUNCTION__)); |
| 9897 | auto *CondBr = BranchInst::Create(State.CFG.PrevBB, nullptr, ConditionBit); |
| 9898 | CondBr->setSuccessor(0, nullptr); |
| 9899 | ReplaceInstWithInst(CurrentTerminator, CondBr); |
| 9900 | } |
| 9901 | |
| 9902 | void VPPredInstPHIRecipe::execute(VPTransformState &State) { |
| 9903 | assert(State.Instance && "Predicated instruction PHI works per instance.")(static_cast <bool> (State.Instance && "Predicated instruction PHI works per instance." ) ? void (0) : __assert_fail ("State.Instance && \"Predicated instruction PHI works per instance.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9903, __extension__ __PRETTY_FUNCTION__)); |
| 9904 | Instruction *ScalarPredInst = |
| 9905 | cast<Instruction>(State.get(getOperand(0), *State.Instance)); |
| 9906 | BasicBlock *PredicatedBB = ScalarPredInst->getParent(); |
| 9907 | BasicBlock *PredicatingBB = PredicatedBB->getSinglePredecessor(); |
| 9908 | assert(PredicatingBB && "Predicated block has no single predecessor.")(static_cast <bool> (PredicatingBB && "Predicated block has no single predecessor." ) ? void (0) : __assert_fail ("PredicatingBB && \"Predicated block has no single predecessor.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9908, __extension__ __PRETTY_FUNCTION__)); |
| 9909 | assert(isa<VPReplicateRecipe>(getOperand(0)) &&(static_cast <bool> (isa<VPReplicateRecipe>(getOperand (0)) && "operand must be VPReplicateRecipe") ? void ( 0) : __assert_fail ("isa<VPReplicateRecipe>(getOperand(0)) && \"operand must be VPReplicateRecipe\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9910, __extension__ __PRETTY_FUNCTION__)) |
| 9910 | "operand must be VPReplicateRecipe")(static_cast <bool> (isa<VPReplicateRecipe>(getOperand (0)) && "operand must be VPReplicateRecipe") ? void ( 0) : __assert_fail ("isa<VPReplicateRecipe>(getOperand(0)) && \"operand must be VPReplicateRecipe\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9910, __extension__ __PRETTY_FUNCTION__)); |
| 9911 | |
| 9912 | // By current pack/unpack logic we need to generate only a single phi node: if |
| 9913 | // a vector value for the predicated instruction exists at this point it means |
| 9914 | // the instruction has vector users only, and a phi for the vector value is |
| 9915 | // needed. In this case the recipe of the predicated instruction is marked to |
| 9916 | // also do that packing, thereby "hoisting" the insert-element sequence. |
| 9917 | // Otherwise, a phi node for the scalar value is needed. |
| 9918 | unsigned Part = State.Instance->Part; |
| 9919 | if (State.hasVectorValue(getOperand(0), Part)) { |
| 9920 | Value *VectorValue = State.get(getOperand(0), Part); |
| 9921 | InsertElementInst *IEI = cast<InsertElementInst>(VectorValue); |
| 9922 | PHINode *VPhi = State.Builder.CreatePHI(IEI->getType(), 2); |
| 9923 | VPhi->addIncoming(IEI->getOperand(0), PredicatingBB); // Unmodified vector. |
| 9924 | VPhi->addIncoming(IEI, PredicatedBB); // New vector with inserted element. |
| 9925 | if (State.hasVectorValue(this, Part)) |
| 9926 | State.reset(this, VPhi, Part); |
| 9927 | else |
| 9928 | State.set(this, VPhi, Part); |
| 9929 | // NOTE: Currently we need to update the value of the operand, so the next |
| 9930 | // predicated iteration inserts its generated value in the correct vector. |
| 9931 | State.reset(getOperand(0), VPhi, Part); |
| 9932 | } else { |
| 9933 | Type *PredInstType = getOperand(0)->getUnderlyingValue()->getType(); |
| 9934 | PHINode *Phi = State.Builder.CreatePHI(PredInstType, 2); |
| 9935 | Phi->addIncoming(PoisonValue::get(ScalarPredInst->getType()), |
| 9936 | PredicatingBB); |
| 9937 | Phi->addIncoming(ScalarPredInst, PredicatedBB); |
| 9938 | if (State.hasScalarValue(this, *State.Instance)) |
| 9939 | State.reset(this, Phi, *State.Instance); |
| 9940 | else |
| 9941 | State.set(this, Phi, *State.Instance); |
| 9942 | // NOTE: Currently we need to update the value of the operand, so the next |
| 9943 | // predicated iteration inserts its generated value in the correct vector. |
| 9944 | State.reset(getOperand(0), Phi, *State.Instance); |
| 9945 | } |
| 9946 | } |
| 9947 | |
| 9948 | void VPWidenMemoryInstructionRecipe::execute(VPTransformState &State) { |
| 9949 | VPValue *StoredValue = isStore() ? getStoredValue() : nullptr; |
| 9950 | |
| 9951 | // Attempt to issue a wide load. |
| 9952 | LoadInst *LI = dyn_cast<LoadInst>(&Ingredient); |
| 9953 | StoreInst *SI = dyn_cast<StoreInst>(&Ingredient); |
| 9954 | |
| 9955 | assert((LI || SI) && "Invalid Load/Store instruction")(static_cast <bool> ((LI || SI) && "Invalid Load/Store instruction" ) ? void (0) : __assert_fail ("(LI || SI) && \"Invalid Load/Store instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9955, __extension__ __PRETTY_FUNCTION__)); |
| 9956 | assert((!SI || StoredValue) && "No stored value provided for widened store")(static_cast <bool> ((!SI || StoredValue) && "No stored value provided for widened store" ) ? void (0) : __assert_fail ("(!SI || StoredValue) && \"No stored value provided for widened store\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9956, __extension__ __PRETTY_FUNCTION__)); |
| 9957 | assert((!LI || !StoredValue) && "Stored value provided for widened load")(static_cast <bool> ((!LI || !StoredValue) && "Stored value provided for widened load" ) ? void (0) : __assert_fail ("(!LI || !StoredValue) && \"Stored value provided for widened load\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 9957, __extension__ __PRETTY_FUNCTION__)); |
| 9958 | |
| 9959 | Type *ScalarDataTy = getLoadStoreType(&Ingredient); |
| 9960 | |
| 9961 | auto *DataTy = VectorType::get(ScalarDataTy, State.VF); |
| 9962 | const Align Alignment = getLoadStoreAlignment(&Ingredient); |
| 9963 | bool CreateGatherScatter = !Consecutive; |
| 9964 | |
| 9965 | auto &Builder = State.Builder; |
| 9966 | InnerLoopVectorizer::VectorParts BlockInMaskParts(State.UF); |
| 9967 | bool isMaskRequired = getMask(); |
| 9968 | if (isMaskRequired) |
| 9969 | for (unsigned Part = 0; Part < State.UF; ++Part) |
| 9970 | BlockInMaskParts[Part] = State.get(getMask(), Part); |
| 9971 | |
| 9972 | const auto CreateVecPtr = [&](unsigned Part, Value *Ptr) -> Value * { |
| 9973 | // Calculate the pointer for the specific unroll-part. |
| 9974 | GetElementPtrInst *PartPtr = nullptr; |
| 9975 | |
| 9976 | bool InBounds = false; |
| 9977 | if (auto *gep = dyn_cast<GetElementPtrInst>(Ptr->stripPointerCasts())) |
| 9978 | InBounds = gep->isInBounds(); |
| 9979 | if (Reverse) { |
| 9980 | // If the address is consecutive but reversed, then the |
| 9981 | // wide store needs to start at the last vector element. |
| 9982 | // RunTimeVF = VScale * VF.getKnownMinValue() |
| 9983 | // For fixed-width VScale is 1, then RunTimeVF = VF.getKnownMinValue() |
| 9984 | Value *RunTimeVF = getRuntimeVF(Builder, Builder.getInt32Ty(), State.VF); |
| 9985 | // NumElt = -Part * RunTimeVF |
| 9986 | Value *NumElt = Builder.CreateMul(Builder.getInt32(-Part), RunTimeVF); |
| 9987 | // LastLane = 1 - RunTimeVF |
| 9988 | Value *LastLane = Builder.CreateSub(Builder.getInt32(1), RunTimeVF); |
| 9989 | PartPtr = |
| 9990 | cast<GetElementPtrInst>(Builder.CreateGEP(ScalarDataTy, Ptr, NumElt)); |
| 9991 | PartPtr->setIsInBounds(InBounds); |
| 9992 | PartPtr = cast<GetElementPtrInst>( |
| 9993 | Builder.CreateGEP(ScalarDataTy, PartPtr, LastLane)); |
| 9994 | PartPtr->setIsInBounds(InBounds); |
| 9995 | if (isMaskRequired) // Reverse of a null all-one mask is a null mask. |
| 9996 | BlockInMaskParts[Part] = |
| 9997 | Builder.CreateVectorReverse(BlockInMaskParts[Part], "reverse"); |
| 9998 | } else { |
| 9999 | Value *Increment = |
| 10000 | createStepForVF(Builder, Builder.getInt32Ty(), State.VF, Part); |
| 10001 | PartPtr = cast<GetElementPtrInst>( |
| 10002 | Builder.CreateGEP(ScalarDataTy, Ptr, Increment)); |
| 10003 | PartPtr->setIsInBounds(InBounds); |
| 10004 | } |
| 10005 | |
| 10006 | unsigned AddressSpace = Ptr->getType()->getPointerAddressSpace(); |
| 10007 | return Builder.CreateBitCast(PartPtr, DataTy->getPointerTo(AddressSpace)); |
| 10008 | }; |
| 10009 | |
| 10010 | // Handle Stores: |
| 10011 | if (SI) { |
| 10012 | State.ILV->setDebugLocFromInst(SI); |
| 10013 | |
| 10014 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 10015 | Instruction *NewSI = nullptr; |
| 10016 | Value *StoredVal = State.get(StoredValue, Part); |
| 10017 | if (CreateGatherScatter) { |
| 10018 | Value *MaskPart = isMaskRequired ? BlockInMaskParts[Part] : nullptr; |
| 10019 | Value *VectorGep = State.get(getAddr(), Part); |
| 10020 | NewSI = Builder.CreateMaskedScatter(StoredVal, VectorGep, Alignment, |
| 10021 | MaskPart); |
| 10022 | } else { |
| 10023 | if (Reverse) { |
| 10024 | // If we store to reverse consecutive memory locations, then we need |
| 10025 | // to reverse the order of elements in the stored value. |
| 10026 | StoredVal = Builder.CreateVectorReverse(StoredVal, "reverse"); |
| 10027 | // We don't want to update the value in the map as it might be used in |
| 10028 | // another expression. So don't call resetVectorValue(StoredVal). |
| 10029 | } |
| 10030 | auto *VecPtr = |
| 10031 | CreateVecPtr(Part, State.get(getAddr(), VPIteration(0, 0))); |
| 10032 | if (isMaskRequired) |
| 10033 | NewSI = Builder.CreateMaskedStore(StoredVal, VecPtr, Alignment, |
| 10034 | BlockInMaskParts[Part]); |
| 10035 | else |
| 10036 | NewSI = Builder.CreateAlignedStore(StoredVal, VecPtr, Alignment); |
| 10037 | } |
| 10038 | State.ILV->addMetadata(NewSI, SI); |
| 10039 | } |
| 10040 | return; |
| 10041 | } |
| 10042 | |
| 10043 | // Handle loads. |
| 10044 | assert(LI && "Must have a load instruction")(static_cast <bool> (LI && "Must have a load instruction" ) ? void (0) : __assert_fail ("LI && \"Must have a load instruction\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10044, __extension__ __PRETTY_FUNCTION__)); |
| 10045 | State.ILV->setDebugLocFromInst(LI); |
| 10046 | for (unsigned Part = 0; Part < State.UF; ++Part) { |
| 10047 | Value *NewLI; |
| 10048 | if (CreateGatherScatter) { |
| 10049 | Value *MaskPart = isMaskRequired ? BlockInMaskParts[Part] : nullptr; |
| 10050 | Value *VectorGep = State.get(getAddr(), Part); |
| 10051 | NewLI = Builder.CreateMaskedGather(DataTy, VectorGep, Alignment, MaskPart, |
| 10052 | nullptr, "wide.masked.gather"); |
| 10053 | State.ILV->addMetadata(NewLI, LI); |
| 10054 | } else { |
| 10055 | auto *VecPtr = |
| 10056 | CreateVecPtr(Part, State.get(getAddr(), VPIteration(0, 0))); |
| 10057 | if (isMaskRequired) |
| 10058 | NewLI = Builder.CreateMaskedLoad( |
| 10059 | DataTy, VecPtr, Alignment, BlockInMaskParts[Part], |
| 10060 | PoisonValue::get(DataTy), "wide.masked.load"); |
| 10061 | else |
| 10062 | NewLI = |
| 10063 | Builder.CreateAlignedLoad(DataTy, VecPtr, Alignment, "wide.load"); |
| 10064 | |
| 10065 | // Add metadata to the load, but setVectorValue to the reverse shuffle. |
| 10066 | State.ILV->addMetadata(NewLI, LI); |
| 10067 | if (Reverse) |
| 10068 | NewLI = Builder.CreateVectorReverse(NewLI, "reverse"); |
| 10069 | } |
| 10070 | |
| 10071 | State.set(this, NewLI, Part); |
| 10072 | } |
| 10073 | } |
| 10074 | |
| 10075 | // Determine how to lower the scalar epilogue, which depends on 1) optimising |
| 10076 | // for minimum code-size, 2) predicate compiler options, 3) loop hints forcing |
| 10077 | // predication, and 4) a TTI hook that analyses whether the loop is suitable |
| 10078 | // for predication. |
| 10079 | static ScalarEpilogueLowering getScalarEpilogueLowering( |
| 10080 | Function *F, Loop *L, LoopVectorizeHints &Hints, ProfileSummaryInfo *PSI, |
| 10081 | BlockFrequencyInfo *BFI, TargetTransformInfo *TTI, TargetLibraryInfo *TLI, |
| 10082 | AssumptionCache *AC, LoopInfo *LI, ScalarEvolution *SE, DominatorTree *DT, |
| 10083 | LoopVectorizationLegality &LVL) { |
| 10084 | // 1) OptSize takes precedence over all other options, i.e. if this is set, |
| 10085 | // don't look at hints or options, and don't request a scalar epilogue. |
| 10086 | // (For PGSO, as shouldOptimizeForSize isn't currently accessible from |
| 10087 | // LoopAccessInfo (due to code dependency and not being able to reliably get |
| 10088 | // PSI/BFI from a loop analysis under NPM), we cannot suppress the collection |
| 10089 | // of strides in LoopAccessInfo::analyzeLoop() and vectorize without |
| 10090 | // versioning when the vectorization is forced, unlike hasOptSize. So revert |
| 10091 | // back to the old way and vectorize with versioning when forced. See D81345.) |
| 10092 | if (F->hasOptSize() || (llvm::shouldOptimizeForSize(L->getHeader(), PSI, BFI, |
| 10093 | PGSOQueryType::IRPass) && |
| 10094 | Hints.getForce() != LoopVectorizeHints::FK_Enabled)) |
| 10095 | return CM_ScalarEpilogueNotAllowedOptSize; |
| 10096 | |
| 10097 | // 2) If set, obey the directives |
| 10098 | if (PreferPredicateOverEpilogue.getNumOccurrences()) { |
| 10099 | switch (PreferPredicateOverEpilogue) { |
| 10100 | case PreferPredicateTy::ScalarEpilogue: |
| 10101 | return CM_ScalarEpilogueAllowed; |
| 10102 | case PreferPredicateTy::PredicateElseScalarEpilogue: |
| 10103 | return CM_ScalarEpilogueNotNeededUsePredicate; |
| 10104 | case PreferPredicateTy::PredicateOrDontVectorize: |
| 10105 | return CM_ScalarEpilogueNotAllowedUsePredicate; |
| 10106 | }; |
| 10107 | } |
| 10108 | |
| 10109 | // 3) If set, obey the hints |
| 10110 | switch (Hints.getPredicate()) { |
| 10111 | case LoopVectorizeHints::FK_Enabled: |
| 10112 | return CM_ScalarEpilogueNotNeededUsePredicate; |
| 10113 | case LoopVectorizeHints::FK_Disabled: |
| 10114 | return CM_ScalarEpilogueAllowed; |
| 10115 | }; |
| 10116 | |
| 10117 | // 4) if the TTI hook indicates this is profitable, request predication. |
| 10118 | if (TTI->preferPredicateOverEpilogue(L, LI, *SE, *AC, TLI, DT, |
| 10119 | LVL.getLAI())) |
| 10120 | return CM_ScalarEpilogueNotNeededUsePredicate; |
| 10121 | |
| 10122 | return CM_ScalarEpilogueAllowed; |
| 10123 | } |
| 10124 | |
| 10125 | Value *VPTransformState::get(VPValue *Def, unsigned Part) { |
| 10126 | // If Values have been set for this Def return the one relevant for \p Part. |
| 10127 | if (hasVectorValue(Def, Part)) |
| 10128 | return Data.PerPartOutput[Def][Part]; |
| 10129 | |
| 10130 | if (!hasScalarValue(Def, {Part, 0})) { |
| 10131 | Value *IRV = Def->getLiveInIRValue(); |
| 10132 | Value *B = ILV->getBroadcastInstrs(IRV); |
| 10133 | set(Def, B, Part); |
| 10134 | return B; |
| 10135 | } |
| 10136 | |
| 10137 | Value *ScalarValue = get(Def, {Part, 0}); |
| 10138 | // If we aren't vectorizing, we can just copy the scalar map values over |
| 10139 | // to the vector map. |
| 10140 | if (VF.isScalar()) { |
| 10141 | set(Def, ScalarValue, Part); |
| 10142 | return ScalarValue; |
| 10143 | } |
| 10144 | |
| 10145 | auto *RepR = dyn_cast<VPReplicateRecipe>(Def); |
| 10146 | bool IsUniform = RepR && RepR->isUniform(); |
| 10147 | |
| 10148 | unsigned LastLane = IsUniform ? 0 : VF.getKnownMinValue() - 1; |
| 10149 | // Check if there is a scalar value for the selected lane. |
| 10150 | if (!hasScalarValue(Def, {Part, LastLane})) { |
| 10151 | // At the moment, VPWidenIntOrFpInductionRecipes can also be uniform. |
| 10152 | assert(isa<VPWidenIntOrFpInductionRecipe>(Def->getDef()) &&(static_cast <bool> (isa<VPWidenIntOrFpInductionRecipe >(Def->getDef()) && "unexpected recipe found to be invariant" ) ? void (0) : __assert_fail ("isa<VPWidenIntOrFpInductionRecipe>(Def->getDef()) && \"unexpected recipe found to be invariant\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10153, __extension__ __PRETTY_FUNCTION__)) |
| 10153 | "unexpected recipe found to be invariant")(static_cast <bool> (isa<VPWidenIntOrFpInductionRecipe >(Def->getDef()) && "unexpected recipe found to be invariant" ) ? void (0) : __assert_fail ("isa<VPWidenIntOrFpInductionRecipe>(Def->getDef()) && \"unexpected recipe found to be invariant\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10153, __extension__ __PRETTY_FUNCTION__)); |
| 10154 | IsUniform = true; |
| 10155 | LastLane = 0; |
| 10156 | } |
| 10157 | |
| 10158 | auto *LastInst = cast<Instruction>(get(Def, {Part, LastLane})); |
| 10159 | // Set the insert point after the last scalarized instruction or after the |
| 10160 | // last PHI, if LastInst is a PHI. This ensures the insertelement sequence |
| 10161 | // will directly follow the scalar definitions. |
| 10162 | auto OldIP = Builder.saveIP(); |
| 10163 | auto NewIP = |
| 10164 | isa<PHINode>(LastInst) |
| 10165 | ? BasicBlock::iterator(LastInst->getParent()->getFirstNonPHI()) |
| 10166 | : std::next(BasicBlock::iterator(LastInst)); |
| 10167 | Builder.SetInsertPoint(&*NewIP); |
| 10168 | |
| 10169 | // However, if we are vectorizing, we need to construct the vector values. |
| 10170 | // If the value is known to be uniform after vectorization, we can just |
| 10171 | // broadcast the scalar value corresponding to lane zero for each unroll |
| 10172 | // iteration. Otherwise, we construct the vector values using |
| 10173 | // insertelement instructions. Since the resulting vectors are stored in |
| 10174 | // State, we will only generate the insertelements once. |
| 10175 | Value *VectorValue = nullptr; |
| 10176 | if (IsUniform) { |
| 10177 | VectorValue = ILV->getBroadcastInstrs(ScalarValue); |
| 10178 | set(Def, VectorValue, Part); |
| 10179 | } else { |
| 10180 | // Initialize packing with insertelements to start from undef. |
| 10181 | assert(!VF.isScalable() && "VF is assumed to be non scalable.")(static_cast <bool> (!VF.isScalable() && "VF is assumed to be non scalable." ) ? void (0) : __assert_fail ("!VF.isScalable() && \"VF is assumed to be non scalable.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10181, __extension__ __PRETTY_FUNCTION__)); |
| 10182 | Value *Undef = PoisonValue::get(VectorType::get(LastInst->getType(), VF)); |
| 10183 | set(Def, Undef, Part); |
| 10184 | for (unsigned Lane = 0; Lane < VF.getKnownMinValue(); ++Lane) |
| 10185 | ILV->packScalarIntoVectorValue(Def, {Part, Lane}, *this); |
| 10186 | VectorValue = get(Def, Part); |
| 10187 | } |
| 10188 | Builder.restoreIP(OldIP); |
| 10189 | return VectorValue; |
| 10190 | } |
| 10191 | |
| 10192 | // Process the loop in the VPlan-native vectorization path. This path builds |
| 10193 | // VPlan upfront in the vectorization pipeline, which allows to apply |
| 10194 | // VPlan-to-VPlan transformations from the very beginning without modifying the |
| 10195 | // input LLVM IR. |
| 10196 | static bool processLoopInVPlanNativePath( |
| 10197 | Loop *L, PredicatedScalarEvolution &PSE, LoopInfo *LI, DominatorTree *DT, |
| 10198 | LoopVectorizationLegality *LVL, TargetTransformInfo *TTI, |
| 10199 | TargetLibraryInfo *TLI, DemandedBits *DB, AssumptionCache *AC, |
| 10200 | OptimizationRemarkEmitter *ORE, BlockFrequencyInfo *BFI, |
| 10201 | ProfileSummaryInfo *PSI, LoopVectorizeHints &Hints, |
| 10202 | LoopVectorizationRequirements &Requirements) { |
| 10203 | |
| 10204 | if (isa<SCEVCouldNotCompute>(PSE.getBackedgeTakenCount())) { |
| 10205 | LLVM_DEBUG(dbgs() << "LV: cannot compute the outer-loop trip count\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: cannot compute the outer-loop trip count\n" ; } } while (false); |
| 10206 | return false; |
| 10207 | } |
| 10208 | assert(EnableVPlanNativePath && "VPlan-native path is disabled.")(static_cast <bool> (EnableVPlanNativePath && "VPlan-native path is disabled." ) ? void (0) : __assert_fail ("EnableVPlanNativePath && \"VPlan-native path is disabled.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10208, __extension__ __PRETTY_FUNCTION__)); |
| 10209 | Function *F = L->getHeader()->getParent(); |
| 10210 | InterleavedAccessInfo IAI(PSE, L, DT, LI, LVL->getLAI()); |
| 10211 | |
| 10212 | ScalarEpilogueLowering SEL = getScalarEpilogueLowering( |
| 10213 | F, L, Hints, PSI, BFI, TTI, TLI, AC, LI, PSE.getSE(), DT, *LVL); |
| 10214 | |
| 10215 | LoopVectorizationCostModel CM(SEL, L, PSE, LI, LVL, *TTI, TLI, DB, AC, ORE, F, |
| 10216 | &Hints, IAI); |
| 10217 | // Use the planner for outer loop vectorization. |
| 10218 | // TODO: CM is not used at this point inside the planner. Turn CM into an |
| 10219 | // optional argument if we don't need it in the future. |
| 10220 | LoopVectorizationPlanner LVP(L, LI, TLI, TTI, LVL, CM, IAI, PSE, Hints, |
| 10221 | Requirements, ORE); |
| 10222 | |
| 10223 | // Get user vectorization factor. |
| 10224 | ElementCount UserVF = Hints.getWidth(); |
| 10225 | |
| 10226 | CM.collectElementTypesForWidening(); |
| 10227 | |
| 10228 | // Plan how to best vectorize, return the best VF and its cost. |
| 10229 | const VectorizationFactor VF = LVP.planInVPlanNativePath(UserVF); |
| 10230 | |
| 10231 | // If we are stress testing VPlan builds, do not attempt to generate vector |
| 10232 | // code. Masked vector code generation support will follow soon. |
| 10233 | // Also, do not attempt to vectorize if no vector code will be produced. |
| 10234 | if (VPlanBuildStressTest || EnableVPlanPredication || |
| 10235 | VectorizationFactor::Disabled() == VF) |
| 10236 | return false; |
| 10237 | |
| 10238 | VPlan &BestPlan = LVP.getBestPlanFor(VF.Width); |
| 10239 | |
| 10240 | { |
| 10241 | GeneratedRTChecks Checks(*PSE.getSE(), DT, LI, |
| 10242 | F->getParent()->getDataLayout()); |
| 10243 | InnerLoopVectorizer LB(L, PSE, LI, DT, TLI, TTI, AC, ORE, VF.Width, 1, LVL, |
| 10244 | &CM, BFI, PSI, Checks); |
| 10245 | LLVM_DEBUG(dbgs() << "Vectorizing outer loop in \""do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "Vectorizing outer loop in \"" << L->getHeader()->getParent()->getName() << "\"\n"; } } while (false) |
| 10246 | << L->getHeader()->getParent()->getName() << "\"\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "Vectorizing outer loop in \"" << L->getHeader()->getParent()->getName() << "\"\n"; } } while (false); |
| 10247 | LVP.executePlan(VF.Width, 1, BestPlan, LB, DT); |
| 10248 | } |
| 10249 | |
| 10250 | // Mark the loop as already vectorized to avoid vectorizing again. |
| 10251 | Hints.setAlreadyVectorized(); |
| 10252 | assert(!verifyFunction(*L->getHeader()->getParent(), &dbgs()))(static_cast <bool> (!verifyFunction(*L->getHeader() ->getParent(), &dbgs())) ? void (0) : __assert_fail ("!verifyFunction(*L->getHeader()->getParent(), &dbgs())" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10252, __extension__ __PRETTY_FUNCTION__)); |
| 10253 | return true; |
| 10254 | } |
| 10255 | |
| 10256 | // Emit a remark if there are stores to floats that required a floating point |
| 10257 | // extension. If the vectorized loop was generated with floating point there |
| 10258 | // will be a performance penalty from the conversion overhead and the change in |
| 10259 | // the vector width. |
| 10260 | static void checkMixedPrecision(Loop *L, OptimizationRemarkEmitter *ORE) { |
| 10261 | SmallVector<Instruction *, 4> Worklist; |
| 10262 | for (BasicBlock *BB : L->getBlocks()) { |
| 10263 | for (Instruction &Inst : *BB) { |
| 10264 | if (auto *S = dyn_cast<StoreInst>(&Inst)) { |
| 10265 | if (S->getValueOperand()->getType()->isFloatTy()) |
| 10266 | Worklist.push_back(S); |
| 10267 | } |
| 10268 | } |
| 10269 | } |
| 10270 | |
| 10271 | // Traverse the floating point stores upwards searching, for floating point |
| 10272 | // conversions. |
| 10273 | SmallPtrSet<const Instruction *, 4> Visited; |
| 10274 | SmallPtrSet<const Instruction *, 4> EmittedRemark; |
| 10275 | while (!Worklist.empty()) { |
| 10276 | auto *I = Worklist.pop_back_val(); |
| 10277 | if (!L->contains(I)) |
| 10278 | continue; |
| 10279 | if (!Visited.insert(I).second) |
| 10280 | continue; |
| 10281 | |
| 10282 | // Emit a remark if the floating point store required a floating |
| 10283 | // point conversion. |
| 10284 | // TODO: More work could be done to identify the root cause such as a |
| 10285 | // constant or a function return type and point the user to it. |
| 10286 | if (isa<FPExtInst>(I) && EmittedRemark.insert(I).second) |
| 10287 | ORE->emit([&]() { |
| 10288 | return OptimizationRemarkAnalysis(LV_NAME"loop-vectorize", "VectorMixedPrecision", |
| 10289 | I->getDebugLoc(), L->getHeader()) |
| 10290 | << "floating point conversion changes vector width. " |
| 10291 | << "Mixed floating point precision requires an up/down " |
| 10292 | << "cast that will negatively impact performance."; |
| 10293 | }); |
| 10294 | |
| 10295 | for (Use &Op : I->operands()) |
| 10296 | if (auto *OpI = dyn_cast<Instruction>(Op)) |
| 10297 | Worklist.push_back(OpI); |
| 10298 | } |
| 10299 | } |
| 10300 | |
| 10301 | LoopVectorizePass::LoopVectorizePass(LoopVectorizeOptions Opts) |
| 10302 | : InterleaveOnlyWhenForced(Opts.InterleaveOnlyWhenForced || |
| 10303 | !EnableLoopInterleaving), |
| 10304 | VectorizeOnlyWhenForced(Opts.VectorizeOnlyWhenForced || |
| 10305 | !EnableLoopVectorization) {} |
| 10306 | |
| 10307 | bool LoopVectorizePass::processLoop(Loop *L) { |
| 10308 | assert((EnableVPlanNativePath || L->isInnermost()) &&(static_cast <bool> ((EnableVPlanNativePath || L->isInnermost ()) && "VPlan-native path is not enabled. Only process inner loops." ) ? void (0) : __assert_fail ("(EnableVPlanNativePath || L->isInnermost()) && \"VPlan-native path is not enabled. Only process inner loops.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10309, __extension__ __PRETTY_FUNCTION__)) |
| 10309 | "VPlan-native path is not enabled. Only process inner loops.")(static_cast <bool> ((EnableVPlanNativePath || L->isInnermost ()) && "VPlan-native path is not enabled. Only process inner loops." ) ? void (0) : __assert_fail ("(EnableVPlanNativePath || L->isInnermost()) && \"VPlan-native path is not enabled. Only process inner loops.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10309, __extension__ __PRETTY_FUNCTION__)); |
| 10310 | |
| 10311 | #ifndef NDEBUG |
| 10312 | const std::string DebugLocStr = getDebugLocString(L); |
| 10313 | #endif /* NDEBUG */ |
| 10314 | |
| 10315 | LLVM_DEBUG(dbgs() << "\nLV: Checking a loop in \""do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "\nLV: Checking a loop in \"" << L->getHeader()->getParent()->getName() << "\" from " << DebugLocStr << "\n"; } } while (false ) |
| 10316 | << L->getHeader()->getParent()->getName() << "\" from "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "\nLV: Checking a loop in \"" << L->getHeader()->getParent()->getName() << "\" from " << DebugLocStr << "\n"; } } while (false ) |
| 10317 | << DebugLocStr << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "\nLV: Checking a loop in \"" << L->getHeader()->getParent()->getName() << "\" from " << DebugLocStr << "\n"; } } while (false ); |
| 10318 | |
| 10319 | LoopVectorizeHints Hints(L, InterleaveOnlyWhenForced, *ORE, TTI); |
| 10320 | |
| 10321 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10322 | dbgs() << "LV: Loop hints:"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10323 | << " force="do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10324 | << (Hints.getForce() == LoopVectorizeHints::FK_Disableddo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10325 | ? "disabled"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10326 | : (Hints.getForce() == LoopVectorizeHints::FK_Enableddo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10327 | ? "enabled"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10328 | : "?"))do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10329 | << " width=" << Hints.getWidth()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false) |
| 10330 | << " interleave=" << Hints.getInterleave() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints:" << " force=" << (Hints.getForce() == LoopVectorizeHints:: FK_Disabled ? "disabled" : (Hints.getForce() == LoopVectorizeHints ::FK_Enabled ? "enabled" : "?")) << " width=" << Hints .getWidth() << " interleave=" << Hints.getInterleave () << "\n"; } } while (false); |
| 10331 | |
| 10332 | // Function containing loop |
| 10333 | Function *F = L->getHeader()->getParent(); |
| 10334 | |
| 10335 | // Looking at the diagnostic output is the only way to determine if a loop |
| 10336 | // was vectorized (other than looking at the IR or machine code), so it |
| 10337 | // is important to generate an optimization remark for each loop. Most of |
| 10338 | // these messages are generated as OptimizationRemarkAnalysis. Remarks |
| 10339 | // generated as OptimizationRemark and OptimizationRemarkMissed are |
| 10340 | // less verbose reporting vectorized loops and unvectorized loops that may |
| 10341 | // benefit from vectorization, respectively. |
| 10342 | |
| 10343 | if (!Hints.allowVectorization(F, L, VectorizeOnlyWhenForced)) { |
| 10344 | LLVM_DEBUG(dbgs() << "LV: Loop hints prevent vectorization.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Loop hints prevent vectorization.\n" ; } } while (false); |
| 10345 | return false; |
| 10346 | } |
| 10347 | |
| 10348 | PredicatedScalarEvolution PSE(*SE, *L); |
| 10349 | |
| 10350 | // Check if it is legal to vectorize the loop. |
| 10351 | LoopVectorizationRequirements Requirements; |
| 10352 | LoopVectorizationLegality LVL(L, PSE, DT, TTI, TLI, AA, F, GetLAA, LI, ORE, |
| 10353 | &Requirements, &Hints, DB, AC, BFI, PSI); |
| 10354 | if (!LVL.canVectorize(EnableVPlanNativePath)) { |
| 10355 | LLVM_DEBUG(dbgs() << "LV: Not vectorizing: Cannot prove legality.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Not vectorizing: Cannot prove legality.\n" ; } } while (false); |
| 10356 | Hints.emitRemarkWithHints(); |
| 10357 | return false; |
| 10358 | } |
| 10359 | |
| 10360 | // Check the function attributes and profiles to find out if this function |
| 10361 | // should be optimized for size. |
| 10362 | ScalarEpilogueLowering SEL = getScalarEpilogueLowering( |
| 10363 | F, L, Hints, PSI, BFI, TTI, TLI, AC, LI, PSE.getSE(), DT, LVL); |
| 10364 | |
| 10365 | // Entrance to the VPlan-native vectorization path. Outer loops are processed |
| 10366 | // here. They may require CFG and instruction level transformations before |
| 10367 | // even evaluating whether vectorization is profitable. Since we cannot modify |
| 10368 | // the incoming IR, we need to build VPlan upfront in the vectorization |
| 10369 | // pipeline. |
| 10370 | if (!L->isInnermost()) |
| 10371 | return processLoopInVPlanNativePath(L, PSE, LI, DT, &LVL, TTI, TLI, DB, AC, |
| 10372 | ORE, BFI, PSI, Hints, Requirements); |
| 10373 | |
| 10374 | assert(L->isInnermost() && "Inner loop expected.")(static_cast <bool> (L->isInnermost() && "Inner loop expected." ) ? void (0) : __assert_fail ("L->isInnermost() && \"Inner loop expected.\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10374, __extension__ __PRETTY_FUNCTION__)); |
| 10375 | |
| 10376 | // Check the loop for a trip count threshold: vectorize loops with a tiny trip |
| 10377 | // count by optimizing for size, to minimize overheads. |
| 10378 | auto ExpectedTC = getSmallBestKnownTC(*SE, L); |
| 10379 | if (ExpectedTC && *ExpectedTC < TinyTripCountVectorThreshold) { |
| 10380 | LLVM_DEBUG(dbgs() << "LV: Found a loop with a very small trip count. "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found a loop with a very small trip count. " << "This loop is worth vectorizing only if no scalar " << "iteration overheads are incurred."; } } while (false ) |
| 10381 | << "This loop is worth vectorizing only if no scalar "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found a loop with a very small trip count. " << "This loop is worth vectorizing only if no scalar " << "iteration overheads are incurred."; } } while (false ) |
| 10382 | << "iteration overheads are incurred.")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found a loop with a very small trip count. " << "This loop is worth vectorizing only if no scalar " << "iteration overheads are incurred."; } } while (false ); |
| 10383 | if (Hints.getForce() == LoopVectorizeHints::FK_Enabled) |
| 10384 | LLVM_DEBUG(dbgs() << " But vectorizing was explicitly forced.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << " But vectorizing was explicitly forced.\n" ; } } while (false); |
| 10385 | else { |
| 10386 | LLVM_DEBUG(dbgs() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "\n"; } } while (false); |
| 10387 | SEL = CM_ScalarEpilogueNotAllowedLowTripLoop; |
| 10388 | } |
| 10389 | } |
| 10390 | |
| 10391 | // Check the function attributes to see if implicit floats are allowed. |
| 10392 | // FIXME: This check doesn't seem possibly correct -- what if the loop is |
| 10393 | // an integer loop and the vector instructions selected are purely integer |
| 10394 | // vector instructions? |
| 10395 | if (F->hasFnAttribute(Attribute::NoImplicitFloat)) { |
| 10396 | reportVectorizationFailure( |
| 10397 | "Can't vectorize when the NoImplicitFloat attribute is used", |
| 10398 | "loop not vectorized due to NoImplicitFloat attribute", |
| 10399 | "NoImplicitFloat", ORE, L); |
| 10400 | Hints.emitRemarkWithHints(); |
| 10401 | return false; |
| 10402 | } |
| 10403 | |
| 10404 | // Check if the target supports potentially unsafe FP vectorization. |
| 10405 | // FIXME: Add a check for the type of safety issue (denormal, signaling) |
| 10406 | // for the target we're vectorizing for, to make sure none of the |
| 10407 | // additional fp-math flags can help. |
| 10408 | if (Hints.isPotentiallyUnsafe() && |
| 10409 | TTI->isFPVectorizationPotentiallyUnsafe()) { |
| 10410 | reportVectorizationFailure( |
| 10411 | "Potentially unsafe FP op prevents vectorization", |
| 10412 | "loop not vectorized due to unsafe FP support.", |
| 10413 | "UnsafeFP", ORE, L); |
| 10414 | Hints.emitRemarkWithHints(); |
| 10415 | return false; |
| 10416 | } |
| 10417 | |
| 10418 | bool AllowOrderedReductions; |
| 10419 | // If the flag is set, use that instead and override the TTI behaviour. |
| 10420 | if (ForceOrderedReductions.getNumOccurrences() > 0) |
| 10421 | AllowOrderedReductions = ForceOrderedReductions; |
| 10422 | else |
| 10423 | AllowOrderedReductions = TTI->enableOrderedReductions(); |
| 10424 | if (!LVL.canVectorizeFPMath(AllowOrderedReductions)) { |
| 10425 | ORE->emit([&]() { |
| 10426 | auto *ExactFPMathInst = Requirements.getExactFPInst(); |
| 10427 | return OptimizationRemarkAnalysisFPCommute(DEBUG_TYPE"loop-vectorize", "CantReorderFPOps", |
| 10428 | ExactFPMathInst->getDebugLoc(), |
| 10429 | ExactFPMathInst->getParent()) |
| 10430 | << "loop not vectorized: cannot prove it is safe to reorder " |
| 10431 | "floating-point operations"; |
| 10432 | }); |
| 10433 | LLVM_DEBUG(dbgs() << "LV: loop not vectorized: cannot prove it is safe to "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: loop not vectorized: cannot prove it is safe to " "reorder floating-point operations\n"; } } while (false) |
| 10434 | "reorder floating-point operations\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: loop not vectorized: cannot prove it is safe to " "reorder floating-point operations\n"; } } while (false); |
| 10435 | Hints.emitRemarkWithHints(); |
| 10436 | return false; |
| 10437 | } |
| 10438 | |
| 10439 | bool UseInterleaved = TTI->enableInterleavedAccessVectorization(); |
| 10440 | InterleavedAccessInfo IAI(PSE, L, DT, LI, LVL.getLAI()); |
| 10441 | |
| 10442 | // If an override option has been passed in for interleaved accesses, use it. |
| 10443 | if (EnableInterleavedMemAccesses.getNumOccurrences() > 0) |
| 10444 | UseInterleaved = EnableInterleavedMemAccesses; |
| 10445 | |
| 10446 | // Analyze interleaved memory accesses. |
| 10447 | if (UseInterleaved) { |
| 10448 | IAI.analyzeInterleaving(useMaskedInterleavedAccesses(*TTI)); |
| 10449 | } |
| 10450 | |
| 10451 | // Use the cost model. |
| 10452 | LoopVectorizationCostModel CM(SEL, L, PSE, LI, &LVL, *TTI, TLI, DB, AC, ORE, |
| 10453 | F, &Hints, IAI); |
| 10454 | CM.collectValuesToIgnore(); |
| 10455 | CM.collectElementTypesForWidening(); |
| 10456 | |
| 10457 | // Use the planner for vectorization. |
| 10458 | LoopVectorizationPlanner LVP(L, LI, TLI, TTI, &LVL, CM, IAI, PSE, Hints, |
| 10459 | Requirements, ORE); |
| 10460 | |
| 10461 | // Get user vectorization factor and interleave count. |
| 10462 | ElementCount UserVF = Hints.getWidth(); |
| 10463 | unsigned UserIC = Hints.getInterleave(); |
| 10464 | |
| 10465 | // Plan how to best vectorize, return the best VF and its cost. |
| 10466 | Optional<VectorizationFactor> MaybeVF = LVP.plan(UserVF, UserIC); |
| 10467 | |
| 10468 | VectorizationFactor VF = VectorizationFactor::Disabled(); |
| 10469 | unsigned IC = 1; |
| 10470 | |
| 10471 | if (MaybeVF) { |
| 10472 | VF = *MaybeVF; |
| 10473 | // Select the interleave count. |
| 10474 | IC = CM.selectInterleaveCount(VF.Width, *VF.Cost.getValue()); |
| 10475 | } |
| 10476 | |
| 10477 | // Identify the diagnostic messages that should be produced. |
| 10478 | std::pair<StringRef, std::string> VecDiagMsg, IntDiagMsg; |
| 10479 | bool VectorizeLoop = true, InterleaveLoop = true; |
| 10480 | if (VF.Width.isScalar()) { |
| 10481 | LLVM_DEBUG(dbgs() << "LV: Vectorization is possible but not beneficial.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Vectorization is possible but not beneficial.\n" ; } } while (false); |
| 10482 | VecDiagMsg = std::make_pair( |
| 10483 | "VectorizationNotBeneficial", |
| 10484 | "the cost-model indicates that vectorization is not beneficial"); |
| 10485 | VectorizeLoop = false; |
| 10486 | } |
| 10487 | |
| 10488 | if (!MaybeVF && UserIC > 1) { |
| 10489 | // Tell the user interleaving was avoided up-front, despite being explicitly |
| 10490 | // requested. |
| 10491 | LLVM_DEBUG(dbgs() << "LV: Ignoring UserIC, because vectorization and "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Ignoring UserIC, because vectorization and " "interleaving should be avoided up front\n"; } } while (false ) |
| 10492 | "interleaving should be avoided up front\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Ignoring UserIC, because vectorization and " "interleaving should be avoided up front\n"; } } while (false ); |
| 10493 | IntDiagMsg = std::make_pair( |
| 10494 | "InterleavingAvoided", |
| 10495 | "Ignoring UserIC, because interleaving was avoided up front"); |
| 10496 | InterleaveLoop = false; |
| 10497 | } else if (IC == 1 && UserIC <= 1) { |
| 10498 | // Tell the user interleaving is not beneficial. |
| 10499 | LLVM_DEBUG(dbgs() << "LV: Interleaving is not beneficial.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving is not beneficial.\n" ; } } while (false); |
| 10500 | IntDiagMsg = std::make_pair( |
| 10501 | "InterleavingNotBeneficial", |
| 10502 | "the cost-model indicates that interleaving is not beneficial"); |
| 10503 | InterleaveLoop = false; |
| 10504 | if (UserIC == 1) { |
| 10505 | IntDiagMsg.first = "InterleavingNotBeneficialAndDisabled"; |
| 10506 | IntDiagMsg.second += |
| 10507 | " and is explicitly disabled or interleave count is set to 1"; |
| 10508 | } |
| 10509 | } else if (IC > 1 && UserIC == 1) { |
| 10510 | // Tell the user interleaving is beneficial, but it explicitly disabled. |
| 10511 | LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving is beneficial but is explicitly disabled." ; } } while (false) |
| 10512 | dbgs() << "LV: Interleaving is beneficial but is explicitly disabled.")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleaving is beneficial but is explicitly disabled." ; } } while (false); |
| 10513 | IntDiagMsg = std::make_pair( |
| 10514 | "InterleavingBeneficialButDisabled", |
| 10515 | "the cost-model indicates that interleaving is beneficial " |
| 10516 | "but is explicitly disabled or interleave count is set to 1"); |
| 10517 | InterleaveLoop = false; |
| 10518 | } |
| 10519 | |
| 10520 | // Override IC if user provided an interleave count. |
| 10521 | IC = UserIC > 0 ? UserIC : IC; |
| 10522 | |
| 10523 | // Emit diagnostic messages, if any. |
| 10524 | const char *VAPassName = Hints.vectorizeAnalysisPassName(); |
| 10525 | if (!VectorizeLoop && !InterleaveLoop) { |
| 10526 | // Do not vectorize or interleaving the loop. |
| 10527 | ORE->emit([&]() { |
| 10528 | return OptimizationRemarkMissed(VAPassName, VecDiagMsg.first, |
| 10529 | L->getStartLoc(), L->getHeader()) |
| 10530 | << VecDiagMsg.second; |
| 10531 | }); |
| 10532 | ORE->emit([&]() { |
| 10533 | return OptimizationRemarkMissed(LV_NAME"loop-vectorize", IntDiagMsg.first, |
| 10534 | L->getStartLoc(), L->getHeader()) |
| 10535 | << IntDiagMsg.second; |
| 10536 | }); |
| 10537 | return false; |
| 10538 | } else if (!VectorizeLoop && InterleaveLoop) { |
| 10539 | LLVM_DEBUG(dbgs() << "LV: Interleave Count is " << IC << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleave Count is " << IC << '\n'; } } while (false); |
| 10540 | ORE->emit([&]() { |
| 10541 | return OptimizationRemarkAnalysis(VAPassName, VecDiagMsg.first, |
| 10542 | L->getStartLoc(), L->getHeader()) |
| 10543 | << VecDiagMsg.second; |
| 10544 | }); |
| 10545 | } else if (VectorizeLoop && !InterleaveLoop) { |
| 10546 | LLVM_DEBUG(dbgs() << "LV: Found a vectorizable loop (" << VF.Widthdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found a vectorizable loop (" << VF.Width << ") in " << DebugLocStr << '\n'; } } while (false) |
| 10547 | << ") in " << DebugLocStr << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found a vectorizable loop (" << VF.Width << ") in " << DebugLocStr << '\n'; } } while (false); |
| 10548 | ORE->emit([&]() { |
| 10549 | return OptimizationRemarkAnalysis(LV_NAME"loop-vectorize", IntDiagMsg.first, |
| 10550 | L->getStartLoc(), L->getHeader()) |
| 10551 | << IntDiagMsg.second; |
| 10552 | }); |
| 10553 | } else if (VectorizeLoop && InterleaveLoop) { |
| 10554 | LLVM_DEBUG(dbgs() << "LV: Found a vectorizable loop (" << VF.Widthdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found a vectorizable loop (" << VF.Width << ") in " << DebugLocStr << '\n'; } } while (false) |
| 10555 | << ") in " << DebugLocStr << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Found a vectorizable loop (" << VF.Width << ") in " << DebugLocStr << '\n'; } } while (false); |
| 10556 | LLVM_DEBUG(dbgs() << "LV: Interleave Count is " << IC << '\n')do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType ("loop-vectorize")) { dbgs() << "LV: Interleave Count is " << IC << '\n'; } } while (false); |
| 10557 | } |
| 10558 | |
| 10559 | bool DisableRuntimeUnroll = false; |
| 10560 | MDNode *OrigLoopID = L->getLoopID(); |
| 10561 | { |
| 10562 | // Optimistically generate runtime checks. Drop them if they turn out to not |
| 10563 | // be profitable. Limit the scope of Checks, so the cleanup happens |
| 10564 | // immediately after vector codegeneration is done. |
| 10565 | GeneratedRTChecks Checks(*PSE.getSE(), DT, LI, |
| 10566 | F->getParent()->getDataLayout()); |
| 10567 | if (!VF.Width.isScalar() || IC > 1) |
| 10568 | Checks.Create(L, *LVL.getLAI(), PSE.getUnionPredicate()); |
| 10569 | |
| 10570 | using namespace ore; |
| 10571 | if (!VectorizeLoop) { |
| 10572 | assert(IC > 1 && "interleave count should not be 1 or 0")(static_cast <bool> (IC > 1 && "interleave count should not be 1 or 0" ) ? void (0) : __assert_fail ("IC > 1 && \"interleave count should not be 1 or 0\"" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10572, __extension__ __PRETTY_FUNCTION__)); |
| 10573 | // If we decided that it is not legal to vectorize the loop, then |
| 10574 | // interleave it. |
| 10575 | InnerLoopUnroller Unroller(L, PSE, LI, DT, TLI, TTI, AC, ORE, IC, &LVL, |
| 10576 | &CM, BFI, PSI, Checks); |
| 10577 | |
| 10578 | VPlan &BestPlan = LVP.getBestPlanFor(VF.Width); |
| 10579 | LVP.executePlan(VF.Width, IC, BestPlan, Unroller, DT); |
| 10580 | |
| 10581 | ORE->emit([&]() { |
| 10582 | return OptimizationRemark(LV_NAME"loop-vectorize", "Interleaved", L->getStartLoc(), |
| 10583 | L->getHeader()) |
| 10584 | << "interleaved loop (interleaved count: " |
| 10585 | << NV("InterleaveCount", IC) << ")"; |
| 10586 | }); |
| 10587 | } else { |
| 10588 | // If we decided that it is *legal* to vectorize the loop, then do it. |
| 10589 | |
| 10590 | // Consider vectorizing the epilogue too if it's profitable. |
| 10591 | VectorizationFactor EpilogueVF = |
| 10592 | CM.selectEpilogueVectorizationFactor(VF.Width, LVP); |
| 10593 | if (EpilogueVF.Width.isVector()) { |
| 10594 | |
| 10595 | // The first pass vectorizes the main loop and creates a scalar epilogue |
| 10596 | // to be vectorized by executing the plan (potentially with a different |
| 10597 | // factor) again shortly afterwards. |
| 10598 | EpilogueLoopVectorizationInfo EPI(VF.Width, IC, EpilogueVF.Width, 1); |
| 10599 | EpilogueVectorizerMainLoop MainILV(L, PSE, LI, DT, TLI, TTI, AC, ORE, |
| 10600 | EPI, &LVL, &CM, BFI, PSI, Checks); |
| 10601 | |
| 10602 | VPlan &BestMainPlan = LVP.getBestPlanFor(EPI.MainLoopVF); |
| 10603 | LVP.executePlan(EPI.MainLoopVF, EPI.MainLoopUF, BestMainPlan, MainILV, |
| 10604 | DT); |
| 10605 | ++LoopsVectorized; |
| 10606 | |
| 10607 | simplifyLoop(L, DT, LI, SE, AC, nullptr, false /* PreserveLCSSA */); |
| 10608 | formLCSSARecursively(*L, *DT, LI, SE); |
| 10609 | |
| 10610 | // Second pass vectorizes the epilogue and adjusts the control flow |
| 10611 | // edges from the first pass. |
| 10612 | EPI.MainLoopVF = EPI.EpilogueVF; |
| 10613 | EPI.MainLoopUF = EPI.EpilogueUF; |
| 10614 | EpilogueVectorizerEpilogueLoop EpilogILV(L, PSE, LI, DT, TLI, TTI, AC, |
| 10615 | ORE, EPI, &LVL, &CM, BFI, PSI, |
| 10616 | Checks); |
| 10617 | |
| 10618 | VPlan &BestEpiPlan = LVP.getBestPlanFor(EPI.EpilogueVF); |
| 10619 | |
| 10620 | // Ensure that the start values for any VPReductionPHIRecipes are |
| 10621 | // updated before vectorising the epilogue loop. |
| 10622 | VPBasicBlock *Header = BestEpiPlan.getEntry()->getEntryBasicBlock(); |
| 10623 | for (VPRecipeBase &R : Header->phis()) { |
| 10624 | if (auto *ReductionPhi = dyn_cast<VPReductionPHIRecipe>(&R)) { |
| 10625 | if (auto *Resume = MainILV.getReductionResumeValue( |
| 10626 | ReductionPhi->getRecurrenceDescriptor())) { |
| 10627 | VPValue *StartVal = new VPValue(Resume); |
| 10628 | BestEpiPlan.addExternalDef(StartVal); |
| 10629 | ReductionPhi->setOperand(0, StartVal); |
| 10630 | } |
| 10631 | } |
| 10632 | } |
| 10633 | |
| 10634 | LVP.executePlan(EPI.EpilogueVF, EPI.EpilogueUF, BestEpiPlan, EpilogILV, |
| 10635 | DT); |
| 10636 | ++LoopsEpilogueVectorized; |
| 10637 | |
| 10638 | if (!MainILV.areSafetyChecksAdded()) |
| 10639 | DisableRuntimeUnroll = true; |
| 10640 | } else { |
| 10641 | InnerLoopVectorizer LB(L, PSE, LI, DT, TLI, TTI, AC, ORE, VF.Width, IC, |
| 10642 | &LVL, &CM, BFI, PSI, Checks); |
| 10643 | |
| 10644 | VPlan &BestPlan = LVP.getBestPlanFor(VF.Width); |
| 10645 | LVP.executePlan(VF.Width, IC, BestPlan, LB, DT); |
| 10646 | ++LoopsVectorized; |
| 10647 | |
| 10648 | // Add metadata to disable runtime unrolling a scalar loop when there |
| 10649 | // are no runtime checks about strides and memory. A scalar loop that is |
| 10650 | // rarely used is not worth unrolling. |
| 10651 | if (!LB.areSafetyChecksAdded()) |
| 10652 | DisableRuntimeUnroll = true; |
| 10653 | } |
| 10654 | // Report the vectorization decision. |
| 10655 | ORE->emit([&]() { |
| 10656 | return OptimizationRemark(LV_NAME"loop-vectorize", "Vectorized", L->getStartLoc(), |
| 10657 | L->getHeader()) |
| 10658 | << "vectorized loop (vectorization width: " |
| 10659 | << NV("VectorizationFactor", VF.Width) |
| 10660 | << ", interleaved count: " << NV("InterleaveCount", IC) << ")"; |
| 10661 | }); |
| 10662 | } |
| 10663 | |
| 10664 | if (ORE->allowExtraAnalysis(LV_NAME"loop-vectorize")) |
| 10665 | checkMixedPrecision(L, ORE); |
| 10666 | } |
| 10667 | |
| 10668 | Optional<MDNode *> RemainderLoopID = |
| 10669 | makeFollowupLoopID(OrigLoopID, {LLVMLoopVectorizeFollowupAll, |
| 10670 | LLVMLoopVectorizeFollowupEpilogue}); |
| 10671 | if (RemainderLoopID.hasValue()) { |
| 10672 | L->setLoopID(RemainderLoopID.getValue()); |
| 10673 | } else { |
| 10674 | if (DisableRuntimeUnroll) |
| 10675 | AddRuntimeUnrollDisableMetaData(L); |
| 10676 | |
| 10677 | // Mark the loop as already vectorized to avoid vectorizing again. |
| 10678 | Hints.setAlreadyVectorized(); |
| 10679 | } |
| 10680 | |
| 10681 | assert(!verifyFunction(*L->getHeader()->getParent(), &dbgs()))(static_cast <bool> (!verifyFunction(*L->getHeader() ->getParent(), &dbgs())) ? void (0) : __assert_fail ("!verifyFunction(*L->getHeader()->getParent(), &dbgs())" , "llvm/lib/Transforms/Vectorize/LoopVectorize.cpp", 10681, __extension__ __PRETTY_FUNCTION__)); |
| 10682 | return true; |
| 10683 | } |
| 10684 | |
| 10685 | LoopVectorizeResult LoopVectorizePass::runImpl( |
| 10686 | Function &F, ScalarEvolution &SE_, LoopInfo &LI_, TargetTransformInfo &TTI_, |
| 10687 | DominatorTree &DT_, BlockFrequencyInfo &BFI_, TargetLibraryInfo *TLI_, |
| 10688 | DemandedBits &DB_, AAResults &AA_, AssumptionCache &AC_, |
| 10689 | std::function<const LoopAccessInfo &(Loop &)> &GetLAA_, |
| 10690 | OptimizationRemarkEmitter &ORE_, ProfileSummaryInfo *PSI_) { |
| 10691 | SE = &SE_; |
| 10692 | LI = &LI_; |
| 10693 | TTI = &TTI_; |
| 10694 | DT = &DT_; |
| 10695 | BFI = &BFI_; |
| 10696 | TLI = TLI_; |
| 10697 | AA = &AA_; |
| 10698 | AC = &AC_; |
| 10699 | GetLAA = &GetLAA_; |
| 10700 | DB = &DB_; |
| 10701 | ORE = &ORE_; |
| 10702 | PSI = PSI_; |
| 10703 | |
| 10704 | // Don't attempt if |
| 10705 | // 1. the target claims to have no vector registers, and |
| 10706 | // 2. interleaving won't help ILP. |
| 10707 | // |
| 10708 | // The second condition is necessary because, even if the target has no |
| 10709 | // vector registers, loop vectorization may still enable scalar |
| 10710 | // interleaving. |
| 10711 | if (!TTI->getNumberOfRegisters(TTI->getRegisterClassForType(true)) && |
| 10712 | TTI->getMaxInterleaveFactor(1) < 2) |
| 10713 | return LoopVectorizeResult(false, false); |
| 10714 | |
| 10715 | bool Changed = false, CFGChanged = false; |
| 10716 | |
| 10717 | // The vectorizer requires loops to be in simplified form. |
| 10718 | // Since simplification may add new inner loops, it has to run before the |
| 10719 | // legality and profitability checks. This means running the loop vectorizer |
| 10720 | // will simplify all loops, regardless of whether anything end up being |
| 10721 | // vectorized. |
| 10722 | for (auto &L : *LI) |
| 10723 | Changed |= CFGChanged |= |
| 10724 | simplifyLoop(L, DT, LI, SE, AC, nullptr, false /* PreserveLCSSA */); |
| 10725 | |
| 10726 | // Build up a worklist of inner-loops to vectorize. This is necessary as |
| 10727 | // the act of vectorizing or partially unrolling a loop creates new loops |
| 10728 | // and can invalidate iterators across the loops. |
| 10729 | SmallVector<Loop *, 8> Worklist; |
| 10730 | |
| 10731 | for (Loop *L : *LI) |
| 10732 | collectSupportedLoops(*L, LI, ORE, Worklist); |
| 10733 | |
| 10734 | LoopsAnalyzed += Worklist.size(); |
| 10735 | |
| 10736 | // Now walk the identified inner loops. |
| 10737 | while (!Worklist.empty()) { |
| 10738 | Loop *L = Worklist.pop_back_val(); |
| 10739 | |
| 10740 | // For the inner loops we actually process, form LCSSA to simplify the |
| 10741 | // transform. |
| 10742 | Changed |= formLCSSARecursively(*L, *DT, LI, SE); |
| 10743 | |
| 10744 | Changed |= CFGChanged |= processLoop(L); |
| 10745 | } |
| 10746 | |
| 10747 | // Process each loop nest in the function. |
| 10748 | return LoopVectorizeResult(Changed, CFGChanged); |
| 10749 | } |
| 10750 | |
| 10751 | PreservedAnalyses LoopVectorizePass::run(Function &F, |
| 10752 | FunctionAnalysisManager &AM) { |
| 10753 | auto &SE = AM.getResult<ScalarEvolutionAnalysis>(F); |
| 10754 | auto &LI = AM.getResult<LoopAnalysis>(F); |
| 10755 | auto &TTI = AM.getResult<TargetIRAnalysis>(F); |
| 10756 | auto &DT = AM.getResult<DominatorTreeAnalysis>(F); |
| 10757 | auto &BFI = AM.getResult<BlockFrequencyAnalysis>(F); |
| 10758 | auto &TLI = AM.getResult<TargetLibraryAnalysis>(F); |
| 10759 | auto &AA = AM.getResult<AAManager>(F); |
| 10760 | auto &AC = AM.getResult<AssumptionAnalysis>(F); |
| 10761 | auto &DB = AM.getResult<DemandedBitsAnalysis>(F); |
| 10762 | auto &ORE = AM.getResult<OptimizationRemarkEmitterAnalysis>(F); |
| 10763 | |
| 10764 | auto &LAM = AM.getResult<LoopAnalysisManagerFunctionProxy>(F).getManager(); |
| 10765 | std::function<const LoopAccessInfo &(Loop &)> GetLAA = |
| 10766 | [&](Loop &L) -> const LoopAccessInfo & { |
| 10767 | LoopStandardAnalysisResults AR = {AA, AC, DT, LI, SE, |
| 10768 | TLI, TTI, nullptr, nullptr, nullptr}; |
| 10769 | return LAM.getResult<LoopAccessAnalysis>(L, AR); |
| 10770 | }; |
| 10771 | auto &MAMProxy = AM.getResult<ModuleAnalysisManagerFunctionProxy>(F); |
| 10772 | ProfileSummaryInfo *PSI = |
| 10773 | MAMProxy.getCachedResult<ProfileSummaryAnalysis>(*F.getParent()); |
| 10774 | LoopVectorizeResult Result = |
| 10775 | runImpl(F, SE, LI, TTI, DT, BFI, &TLI, DB, AA, AC, GetLAA, ORE, PSI); |
| 10776 | if (!Result.MadeAnyChange) |
| 10777 | return PreservedAnalyses::all(); |
| 10778 | PreservedAnalyses PA; |
| 10779 | |
| 10780 | // We currently do not preserve loopinfo/dominator analyses with outer loop |
| 10781 | // vectorization. Until this is addressed, mark these analyses as preserved |
| 10782 | // only for non-VPlan-native path. |
| 10783 | // TODO: Preserve Loop and Dominator analyses for VPlan-native path. |
| 10784 | if (!EnableVPlanNativePath) { |
| 10785 | PA.preserve<LoopAnalysis>(); |
| 10786 | PA.preserve<DominatorTreeAnalysis>(); |
| 10787 | } |
| 10788 | |
| 10789 | if (Result.MadeCFGChange) { |
| 10790 | // Making CFG changes likely means a loop got vectorized. Indicate that |
| 10791 | // extra simplification passes should be run. |
| 10792 | // TODO: MadeCFGChanges is not a prefect proxy. Extra passes should only |
| 10793 | // be run if runtime checks have been added. |
| 10794 | AM.getResult<ShouldRunExtraVectorPasses>(F); |
| 10795 | PA.preserve<ShouldRunExtraVectorPasses>(); |
| 10796 | } else { |
| 10797 | PA.preserveSet<CFGAnalyses>(); |
| 10798 | } |
| 10799 | return PA; |
| 10800 | } |
| 10801 | |
| 10802 | void LoopVectorizePass::printPipeline( |
| 10803 | raw_ostream &OS, function_ref<StringRef(StringRef)> MapClassName2PassName) { |
| 10804 | static_cast<PassInfoMixin<LoopVectorizePass> *>(this)->printPipeline( |
| 10805 | OS, MapClassName2PassName); |
| 10806 | |
| 10807 | OS << "<"; |
| 10808 | OS << (InterleaveOnlyWhenForced ? "" : "no-") << "interleave-forced-only;"; |
| 10809 | OS << (VectorizeOnlyWhenForced ? "" : "no-") << "vectorize-forced-only;"; |
| 10810 | OS << ">"; |
| 10811 | } |