Bug Summary

File:lib/Transforms/Vectorize/BBVectorize.cpp
Location:line 2629, column 11
Description:Value stored to 'I2T' is never read

Annotated Source Code

1//===- BBVectorize.cpp - A Basic-Block Vectorizer -------------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements a basic-block vectorization pass. The algorithm was
11// inspired by that used by the Vienna MAP Vectorizor by Franchetti and Kral,
12// et al. It works by looking for chains of pairable operations and then
13// pairing them.
14//
15//===----------------------------------------------------------------------===//
16
17#define BBV_NAME"bb-vectorize" "bb-vectorize"
18#include "llvm/Transforms/Vectorize.h"
19#include "llvm/ADT/DenseMap.h"
20#include "llvm/ADT/DenseSet.h"
21#include "llvm/ADT/STLExtras.h"
22#include "llvm/ADT/SmallSet.h"
23#include "llvm/ADT/SmallVector.h"
24#include "llvm/ADT/Statistic.h"
25#include "llvm/ADT/StringExtras.h"
26#include "llvm/Analysis/AliasAnalysis.h"
27#include "llvm/Analysis/AliasSetTracker.h"
28#include "llvm/Analysis/ScalarEvolution.h"
29#include "llvm/Analysis/ScalarEvolutionExpressions.h"
30#include "llvm/Analysis/TargetTransformInfo.h"
31#include "llvm/Analysis/ValueTracking.h"
32#include "llvm/IR/Constants.h"
33#include "llvm/IR/DataLayout.h"
34#include "llvm/IR/DerivedTypes.h"
35#include "llvm/IR/Dominators.h"
36#include "llvm/IR/Function.h"
37#include "llvm/IR/Instructions.h"
38#include "llvm/IR/IntrinsicInst.h"
39#include "llvm/IR/Intrinsics.h"
40#include "llvm/IR/LLVMContext.h"
41#include "llvm/IR/Metadata.h"
42#include "llvm/IR/Type.h"
43#include "llvm/IR/ValueHandle.h"
44#include "llvm/Pass.h"
45#include "llvm/Support/CommandLine.h"
46#include "llvm/Support/Debug.h"
47#include "llvm/Support/raw_ostream.h"
48#include "llvm/Transforms/Utils/Local.h"
49#include <algorithm>
50using namespace llvm;
51
52#define DEBUG_TYPE"bb-vectorize" BBV_NAME"bb-vectorize"
53
54static cl::opt<bool>
55IgnoreTargetInfo("bb-vectorize-ignore-target-info", cl::init(false),
56 cl::Hidden, cl::desc("Ignore target information"));
57
58static cl::opt<unsigned>
59ReqChainDepth("bb-vectorize-req-chain-depth", cl::init(6), cl::Hidden,
60 cl::desc("The required chain depth for vectorization"));
61
62static cl::opt<bool>
63UseChainDepthWithTI("bb-vectorize-use-chain-depth", cl::init(false),
64 cl::Hidden, cl::desc("Use the chain depth requirement with"
65 " target information"));
66
67static cl::opt<unsigned>
68SearchLimit("bb-vectorize-search-limit", cl::init(400), cl::Hidden,
69 cl::desc("The maximum search distance for instruction pairs"));
70
71static cl::opt<bool>
72SplatBreaksChain("bb-vectorize-splat-breaks-chain", cl::init(false), cl::Hidden,
73 cl::desc("Replicating one element to a pair breaks the chain"));
74
75static cl::opt<unsigned>
76VectorBits("bb-vectorize-vector-bits", cl::init(128), cl::Hidden,
77 cl::desc("The size of the native vector registers"));
78
79static cl::opt<unsigned>
80MaxIter("bb-vectorize-max-iter", cl::init(0), cl::Hidden,
81 cl::desc("The maximum number of pairing iterations"));
82
83static cl::opt<bool>
84Pow2LenOnly("bb-vectorize-pow2-len-only", cl::init(false), cl::Hidden,
85 cl::desc("Don't try to form non-2^n-length vectors"));
86
87static cl::opt<unsigned>
88MaxInsts("bb-vectorize-max-instr-per-group", cl::init(500), cl::Hidden,
89 cl::desc("The maximum number of pairable instructions per group"));
90
91static cl::opt<unsigned>
92MaxPairs("bb-vectorize-max-pairs-per-group", cl::init(3000), cl::Hidden,
93 cl::desc("The maximum number of candidate instruction pairs per group"));
94
95static cl::opt<unsigned>
96MaxCandPairsForCycleCheck("bb-vectorize-max-cycle-check-pairs", cl::init(200),
97 cl::Hidden, cl::desc("The maximum number of candidate pairs with which to use"
98 " a full cycle check"));
99
100static cl::opt<bool>
101NoBools("bb-vectorize-no-bools", cl::init(false), cl::Hidden,
102 cl::desc("Don't try to vectorize boolean (i1) values"));
103
104static cl::opt<bool>
105NoInts("bb-vectorize-no-ints", cl::init(false), cl::Hidden,
106 cl::desc("Don't try to vectorize integer values"));
107
108static cl::opt<bool>
109NoFloats("bb-vectorize-no-floats", cl::init(false), cl::Hidden,
110 cl::desc("Don't try to vectorize floating-point values"));
111
112// FIXME: This should default to false once pointer vector support works.
113static cl::opt<bool>
114NoPointers("bb-vectorize-no-pointers", cl::init(/*false*/ true), cl::Hidden,
115 cl::desc("Don't try to vectorize pointer values"));
116
117static cl::opt<bool>
118NoCasts("bb-vectorize-no-casts", cl::init(false), cl::Hidden,
119 cl::desc("Don't try to vectorize casting (conversion) operations"));
120
121static cl::opt<bool>
122NoMath("bb-vectorize-no-math", cl::init(false), cl::Hidden,
123 cl::desc("Don't try to vectorize floating-point math intrinsics"));
124
125static cl::opt<bool>
126 NoBitManipulation("bb-vectorize-no-bitmanip", cl::init(false), cl::Hidden,
127 cl::desc("Don't try to vectorize BitManipulation intrinsics"));
128
129static cl::opt<bool>
130NoFMA("bb-vectorize-no-fma", cl::init(false), cl::Hidden,
131 cl::desc("Don't try to vectorize the fused-multiply-add intrinsic"));
132
133static cl::opt<bool>
134NoSelect("bb-vectorize-no-select", cl::init(false), cl::Hidden,
135 cl::desc("Don't try to vectorize select instructions"));
136
137static cl::opt<bool>
138NoCmp("bb-vectorize-no-cmp", cl::init(false), cl::Hidden,
139 cl::desc("Don't try to vectorize comparison instructions"));
140
141static cl::opt<bool>
142NoGEP("bb-vectorize-no-gep", cl::init(false), cl::Hidden,
143 cl::desc("Don't try to vectorize getelementptr instructions"));
144
145static cl::opt<bool>
146NoMemOps("bb-vectorize-no-mem-ops", cl::init(false), cl::Hidden,
147 cl::desc("Don't try to vectorize loads and stores"));
148
149static cl::opt<bool>
150AlignedOnly("bb-vectorize-aligned-only", cl::init(false), cl::Hidden,
151 cl::desc("Only generate aligned loads and stores"));
152
153static cl::opt<bool>
154NoMemOpBoost("bb-vectorize-no-mem-op-boost",
155 cl::init(false), cl::Hidden,
156 cl::desc("Don't boost the chain-depth contribution of loads and stores"));
157
158static cl::opt<bool>
159FastDep("bb-vectorize-fast-dep", cl::init(false), cl::Hidden,
160 cl::desc("Use a fast instruction dependency analysis"));
161
162#ifndef NDEBUG
163static cl::opt<bool>
164DebugInstructionExamination("bb-vectorize-debug-instruction-examination",
165 cl::init(false), cl::Hidden,
166 cl::desc("When debugging is enabled, output information on the"
167 " instruction-examination process"));
168static cl::opt<bool>
169DebugCandidateSelection("bb-vectorize-debug-candidate-selection",
170 cl::init(false), cl::Hidden,
171 cl::desc("When debugging is enabled, output information on the"
172 " candidate-selection process"));
173static cl::opt<bool>
174DebugPairSelection("bb-vectorize-debug-pair-selection",
175 cl::init(false), cl::Hidden,
176 cl::desc("When debugging is enabled, output information on the"
177 " pair-selection process"));
178static cl::opt<bool>
179DebugCycleCheck("bb-vectorize-debug-cycle-check",
180 cl::init(false), cl::Hidden,
181 cl::desc("When debugging is enabled, output information on the"
182 " cycle-checking process"));
183
184static cl::opt<bool>
185PrintAfterEveryPair("bb-vectorize-debug-print-after-every-pair",
186 cl::init(false), cl::Hidden,
187 cl::desc("When debugging is enabled, dump the basic block after"
188 " every pair is fused"));
189#endif
190
191STATISTIC(NumFusedOps, "Number of operations fused by bb-vectorize")static llvm::Statistic NumFusedOps = { "bb-vectorize", "Number of operations fused by bb-vectorize"
, 0, 0 }
;
192
193namespace {
194 struct BBVectorize : public BasicBlockPass {
195 static char ID; // Pass identification, replacement for typeid
196
197 const VectorizeConfig Config;
198
199 BBVectorize(const VectorizeConfig &C = VectorizeConfig())
200 : BasicBlockPass(ID), Config(C) {
201 initializeBBVectorizePass(*PassRegistry::getPassRegistry());
202 }
203
204 BBVectorize(Pass *P, const VectorizeConfig &C)
205 : BasicBlockPass(ID), Config(C) {
206 AA = &P->getAnalysis<AliasAnalysis>();
207 DT = &P->getAnalysis<DominatorTreeWrapperPass>().getDomTree();
208 SE = &P->getAnalysis<ScalarEvolution>();
209 DataLayoutPass *DLP = P->getAnalysisIfAvailable<DataLayoutPass>();
210 DL = DLP ? &DLP->getDataLayout() : nullptr;
211 TTI = IgnoreTargetInfo ? nullptr : &P->getAnalysis<TargetTransformInfo>();
212 }
213
214 typedef std::pair<Value *, Value *> ValuePair;
215 typedef std::pair<ValuePair, int> ValuePairWithCost;
216 typedef std::pair<ValuePair, size_t> ValuePairWithDepth;
217 typedef std::pair<ValuePair, ValuePair> VPPair; // A ValuePair pair
218 typedef std::pair<VPPair, unsigned> VPPairWithType;
219
220 AliasAnalysis *AA;
221 DominatorTree *DT;
222 ScalarEvolution *SE;
223 const DataLayout *DL;
224 const TargetTransformInfo *TTI;
225
226 // FIXME: const correct?
227
228 bool vectorizePairs(BasicBlock &BB, bool NonPow2Len = false);
229
230 bool getCandidatePairs(BasicBlock &BB,
231 BasicBlock::iterator &Start,
232 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
233 DenseSet<ValuePair> &FixedOrderPairs,
234 DenseMap<ValuePair, int> &CandidatePairCostSavings,
235 std::vector<Value *> &PairableInsts, bool NonPow2Len);
236
237 // FIXME: The current implementation does not account for pairs that
238 // are connected in multiple ways. For example:
239 // C1 = A1 / A2; C2 = A2 / A1 (which may be both direct and a swap)
240 enum PairConnectionType {
241 PairConnectionDirect,
242 PairConnectionSwap,
243 PairConnectionSplat
244 };
245
246 void computeConnectedPairs(
247 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
248 DenseSet<ValuePair> &CandidatePairsSet,
249 std::vector<Value *> &PairableInsts,
250 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
251 DenseMap<VPPair, unsigned> &PairConnectionTypes);
252
253 void buildDepMap(BasicBlock &BB,
254 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
255 std::vector<Value *> &PairableInsts,
256 DenseSet<ValuePair> &PairableInstUsers);
257
258 void choosePairs(DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
259 DenseSet<ValuePair> &CandidatePairsSet,
260 DenseMap<ValuePair, int> &CandidatePairCostSavings,
261 std::vector<Value *> &PairableInsts,
262 DenseSet<ValuePair> &FixedOrderPairs,
263 DenseMap<VPPair, unsigned> &PairConnectionTypes,
264 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
265 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps,
266 DenseSet<ValuePair> &PairableInstUsers,
267 DenseMap<Value *, Value *>& ChosenPairs);
268
269 void fuseChosenPairs(BasicBlock &BB,
270 std::vector<Value *> &PairableInsts,
271 DenseMap<Value *, Value *>& ChosenPairs,
272 DenseSet<ValuePair> &FixedOrderPairs,
273 DenseMap<VPPair, unsigned> &PairConnectionTypes,
274 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
275 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps);
276
277
278 bool isInstVectorizable(Instruction *I, bool &IsSimpleLoadStore);
279
280 bool areInstsCompatible(Instruction *I, Instruction *J,
281 bool IsSimpleLoadStore, bool NonPow2Len,
282 int &CostSavings, int &FixedOrder);
283
284 bool trackUsesOfI(DenseSet<Value *> &Users,
285 AliasSetTracker &WriteSet, Instruction *I,
286 Instruction *J, bool UpdateUsers = true,
287 DenseSet<ValuePair> *LoadMoveSetPairs = nullptr);
288
289 void computePairsConnectedTo(
290 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
291 DenseSet<ValuePair> &CandidatePairsSet,
292 std::vector<Value *> &PairableInsts,
293 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
294 DenseMap<VPPair, unsigned> &PairConnectionTypes,
295 ValuePair P);
296
297 bool pairsConflict(ValuePair P, ValuePair Q,
298 DenseSet<ValuePair> &PairableInstUsers,
299 DenseMap<ValuePair, std::vector<ValuePair> >
300 *PairableInstUserMap = nullptr,
301 DenseSet<VPPair> *PairableInstUserPairSet = nullptr);
302
303 bool pairWillFormCycle(ValuePair P,
304 DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUsers,
305 DenseSet<ValuePair> &CurrentPairs);
306
307 void pruneDAGFor(
308 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
309 std::vector<Value *> &PairableInsts,
310 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
311 DenseSet<ValuePair> &PairableInstUsers,
312 DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
313 DenseSet<VPPair> &PairableInstUserPairSet,
314 DenseMap<Value *, Value *> &ChosenPairs,
315 DenseMap<ValuePair, size_t> &DAG,
316 DenseSet<ValuePair> &PrunedDAG, ValuePair J,
317 bool UseCycleCheck);
318
319 void buildInitialDAGFor(
320 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
321 DenseSet<ValuePair> &CandidatePairsSet,
322 std::vector<Value *> &PairableInsts,
323 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
324 DenseSet<ValuePair> &PairableInstUsers,
325 DenseMap<Value *, Value *> &ChosenPairs,
326 DenseMap<ValuePair, size_t> &DAG, ValuePair J);
327
328 void findBestDAGFor(
329 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
330 DenseSet<ValuePair> &CandidatePairsSet,
331 DenseMap<ValuePair, int> &CandidatePairCostSavings,
332 std::vector<Value *> &PairableInsts,
333 DenseSet<ValuePair> &FixedOrderPairs,
334 DenseMap<VPPair, unsigned> &PairConnectionTypes,
335 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
336 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps,
337 DenseSet<ValuePair> &PairableInstUsers,
338 DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
339 DenseSet<VPPair> &PairableInstUserPairSet,
340 DenseMap<Value *, Value *> &ChosenPairs,
341 DenseSet<ValuePair> &BestDAG, size_t &BestMaxDepth,
342 int &BestEffSize, Value *II, std::vector<Value *>&JJ,
343 bool UseCycleCheck);
344
345 Value *getReplacementPointerInput(LLVMContext& Context, Instruction *I,
346 Instruction *J, unsigned o);
347
348 void fillNewShuffleMask(LLVMContext& Context, Instruction *J,
349 unsigned MaskOffset, unsigned NumInElem,
350 unsigned NumInElem1, unsigned IdxOffset,
351 std::vector<Constant*> &Mask);
352
353 Value *getReplacementShuffleMask(LLVMContext& Context, Instruction *I,
354 Instruction *J);
355
356 bool expandIEChain(LLVMContext& Context, Instruction *I, Instruction *J,
357 unsigned o, Value *&LOp, unsigned numElemL,
358 Type *ArgTypeL, Type *ArgTypeR, bool IBeforeJ,
359 unsigned IdxOff = 0);
360
361 Value *getReplacementInput(LLVMContext& Context, Instruction *I,
362 Instruction *J, unsigned o, bool IBeforeJ);
363
364 void getReplacementInputsForPair(LLVMContext& Context, Instruction *I,
365 Instruction *J, SmallVectorImpl<Value *> &ReplacedOperands,
366 bool IBeforeJ);
367
368 void replaceOutputsOfPair(LLVMContext& Context, Instruction *I,
369 Instruction *J, Instruction *K,
370 Instruction *&InsertionPt, Instruction *&K1,
371 Instruction *&K2);
372
373 void collectPairLoadMoveSet(BasicBlock &BB,
374 DenseMap<Value *, Value *> &ChosenPairs,
375 DenseMap<Value *, std::vector<Value *> > &LoadMoveSet,
376 DenseSet<ValuePair> &LoadMoveSetPairs,
377 Instruction *I);
378
379 void collectLoadMoveSet(BasicBlock &BB,
380 std::vector<Value *> &PairableInsts,
381 DenseMap<Value *, Value *> &ChosenPairs,
382 DenseMap<Value *, std::vector<Value *> > &LoadMoveSet,
383 DenseSet<ValuePair> &LoadMoveSetPairs);
384
385 bool canMoveUsesOfIAfterJ(BasicBlock &BB,
386 DenseSet<ValuePair> &LoadMoveSetPairs,
387 Instruction *I, Instruction *J);
388
389 void moveUsesOfIAfterJ(BasicBlock &BB,
390 DenseSet<ValuePair> &LoadMoveSetPairs,
391 Instruction *&InsertionPt,
392 Instruction *I, Instruction *J);
393
394 bool vectorizeBB(BasicBlock &BB) {
395 if (skipOptnoneFunction(BB))
396 return false;
397 if (!DT->isReachableFromEntry(&BB)) {
398 DEBUG(dbgs() << "BBV: skipping unreachable " << BB.getName() <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: skipping unreachable "
<< BB.getName() << " in " << BB.getParent(
)->getName() << "\n"; } } while (0)
399 " in " << BB.getParent()->getName() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: skipping unreachable "
<< BB.getName() << " in " << BB.getParent(
)->getName() << "\n"; } } while (0)
;
400 return false;
401 }
402
403 DEBUG(if (TTI) dbgs() << "BBV: using target information\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (TTI) dbgs() << "BBV: using target information\n"
; } } while (0)
;
404
405 bool changed = false;
406 // Iterate a sufficient number of times to merge types of size 1 bit,
407 // then 2 bits, then 4, etc. up to half of the target vector width of the
408 // target vector register.
409 unsigned n = 1;
410 for (unsigned v = 2;
411 (TTI || v <= Config.VectorBits) &&
412 (!Config.MaxIter || n <= Config.MaxIter);
413 v *= 2, ++n) {
414 DEBUG(dbgs() << "BBV: fusing loop #" << n <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusing loop #" <<
n << " for " << BB.getName() << " in " <<
BB.getParent()->getName() << "...\n"; } } while (0)
415 " for " << BB.getName() << " in " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusing loop #" <<
n << " for " << BB.getName() << " in " <<
BB.getParent()->getName() << "...\n"; } } while (0)
416 BB.getParent()->getName() << "...\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusing loop #" <<
n << " for " << BB.getName() << " in " <<
BB.getParent()->getName() << "...\n"; } } while (0)
;
417 if (vectorizePairs(BB))
418 changed = true;
419 else
420 break;
421 }
422
423 if (changed && !Pow2LenOnly) {
424 ++n;
425 for (; !Config.MaxIter || n <= Config.MaxIter; ++n) {
426 DEBUG(dbgs() << "BBV: fusing for non-2^n-length vectors loop #: " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusing for non-2^n-length vectors loop #: "
<< n << " for " << BB.getName() << " in "
<< BB.getParent()->getName() << "...\n"; } } while
(0)
427 n << " for " << BB.getName() << " in " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusing for non-2^n-length vectors loop #: "
<< n << " for " << BB.getName() << " in "
<< BB.getParent()->getName() << "...\n"; } } while
(0)
428 BB.getParent()->getName() << "...\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusing for non-2^n-length vectors loop #: "
<< n << " for " << BB.getName() << " in "
<< BB.getParent()->getName() << "...\n"; } } while
(0)
;
429 if (!vectorizePairs(BB, true)) break;
430 }
431 }
432
433 DEBUG(dbgs() << "BBV: done!\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: done!\n"; } } while
(0)
;
434 return changed;
435 }
436
437 bool runOnBasicBlock(BasicBlock &BB) override {
438 // OptimizeNone check deferred to vectorizeBB().
439
440 AA = &getAnalysis<AliasAnalysis>();
441 DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
442 SE = &getAnalysis<ScalarEvolution>();
443 DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
444 DL = DLP ? &DLP->getDataLayout() : nullptr;
445 TTI = IgnoreTargetInfo ? nullptr : &getAnalysis<TargetTransformInfo>();
446
447 return vectorizeBB(BB);
448 }
449
450 void getAnalysisUsage(AnalysisUsage &AU) const override {
451 BasicBlockPass::getAnalysisUsage(AU);
452 AU.addRequired<AliasAnalysis>();
453 AU.addRequired<DominatorTreeWrapperPass>();
454 AU.addRequired<ScalarEvolution>();
455 AU.addRequired<TargetTransformInfo>();
456 AU.addPreserved<AliasAnalysis>();
457 AU.addPreserved<DominatorTreeWrapperPass>();
458 AU.addPreserved<ScalarEvolution>();
459 AU.setPreservesCFG();
460 }
461
462 static inline VectorType *getVecTypeForPair(Type *ElemTy, Type *Elem2Ty) {
463 assert(ElemTy->getScalarType() == Elem2Ty->getScalarType() &&((ElemTy->getScalarType() == Elem2Ty->getScalarType() &&
"Cannot form vector from incompatible scalar types") ? static_cast
<void> (0) : __assert_fail ("ElemTy->getScalarType() == Elem2Ty->getScalarType() && \"Cannot form vector from incompatible scalar types\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 464, __PRETTY_FUNCTION__))
464 "Cannot form vector from incompatible scalar types")((ElemTy->getScalarType() == Elem2Ty->getScalarType() &&
"Cannot form vector from incompatible scalar types") ? static_cast
<void> (0) : __assert_fail ("ElemTy->getScalarType() == Elem2Ty->getScalarType() && \"Cannot form vector from incompatible scalar types\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 464, __PRETTY_FUNCTION__))
;
465 Type *STy = ElemTy->getScalarType();
466
467 unsigned numElem;
468 if (VectorType *VTy = dyn_cast<VectorType>(ElemTy)) {
469 numElem = VTy->getNumElements();
470 } else {
471 numElem = 1;
472 }
473
474 if (VectorType *VTy = dyn_cast<VectorType>(Elem2Ty)) {
475 numElem += VTy->getNumElements();
476 } else {
477 numElem += 1;
478 }
479
480 return VectorType::get(STy, numElem);
481 }
482
483 static inline void getInstructionTypes(Instruction *I,
484 Type *&T1, Type *&T2) {
485 if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
486 // For stores, it is the value type, not the pointer type that matters
487 // because the value is what will come from a vector register.
488
489 Value *IVal = SI->getValueOperand();
490 T1 = IVal->getType();
491 } else {
492 T1 = I->getType();
493 }
494
495 if (CastInst *CI = dyn_cast<CastInst>(I))
496 T2 = CI->getSrcTy();
497 else
498 T2 = T1;
499
500 if (SelectInst *SI = dyn_cast<SelectInst>(I)) {
501 T2 = SI->getCondition()->getType();
502 } else if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(I)) {
503 T2 = SI->getOperand(0)->getType();
504 } else if (CmpInst *CI = dyn_cast<CmpInst>(I)) {
505 T2 = CI->getOperand(0)->getType();
506 }
507 }
508
509 // Returns the weight associated with the provided value. A chain of
510 // candidate pairs has a length given by the sum of the weights of its
511 // members (one weight per pair; the weight of each member of the pair
512 // is assumed to be the same). This length is then compared to the
513 // chain-length threshold to determine if a given chain is significant
514 // enough to be vectorized. The length is also used in comparing
515 // candidate chains where longer chains are considered to be better.
516 // Note: when this function returns 0, the resulting instructions are
517 // not actually fused.
518 inline size_t getDepthFactor(Value *V) {
519 // InsertElement and ExtractElement have a depth factor of zero. This is
520 // for two reasons: First, they cannot be usefully fused. Second, because
521 // the pass generates a lot of these, they can confuse the simple metric
522 // used to compare the dags in the next iteration. Thus, giving them a
523 // weight of zero allows the pass to essentially ignore them in
524 // subsequent iterations when looking for vectorization opportunities
525 // while still tracking dependency chains that flow through those
526 // instructions.
527 if (isa<InsertElementInst>(V) || isa<ExtractElementInst>(V))
528 return 0;
529
530 // Give a load or store half of the required depth so that load/store
531 // pairs will vectorize.
532 if (!Config.NoMemOpBoost && (isa<LoadInst>(V) || isa<StoreInst>(V)))
533 return Config.ReqChainDepth/2;
534
535 return 1;
536 }
537
538 // Returns the cost of the provided instruction using TTI.
539 // This does not handle loads and stores.
540 unsigned getInstrCost(unsigned Opcode, Type *T1, Type *T2,
541 TargetTransformInfo::OperandValueKind Op1VK =
542 TargetTransformInfo::OK_AnyValue,
543 TargetTransformInfo::OperandValueKind Op2VK =
544 TargetTransformInfo::OK_AnyValue) {
545 switch (Opcode) {
546 default: break;
547 case Instruction::GetElementPtr:
548 // We mark this instruction as zero-cost because scalar GEPs are usually
549 // lowered to the instruction addressing mode. At the moment we don't
550 // generate vector GEPs.
551 return 0;
552 case Instruction::Br:
553 return TTI->getCFInstrCost(Opcode);
554 case Instruction::PHI:
555 return 0;
556 case Instruction::Add:
557 case Instruction::FAdd:
558 case Instruction::Sub:
559 case Instruction::FSub:
560 case Instruction::Mul:
561 case Instruction::FMul:
562 case Instruction::UDiv:
563 case Instruction::SDiv:
564 case Instruction::FDiv:
565 case Instruction::URem:
566 case Instruction::SRem:
567 case Instruction::FRem:
568 case Instruction::Shl:
569 case Instruction::LShr:
570 case Instruction::AShr:
571 case Instruction::And:
572 case Instruction::Or:
573 case Instruction::Xor:
574 return TTI->getArithmeticInstrCost(Opcode, T1, Op1VK, Op2VK);
575 case Instruction::Select:
576 case Instruction::ICmp:
577 case Instruction::FCmp:
578 return TTI->getCmpSelInstrCost(Opcode, T1, T2);
579 case Instruction::ZExt:
580 case Instruction::SExt:
581 case Instruction::FPToUI:
582 case Instruction::FPToSI:
583 case Instruction::FPExt:
584 case Instruction::PtrToInt:
585 case Instruction::IntToPtr:
586 case Instruction::SIToFP:
587 case Instruction::UIToFP:
588 case Instruction::Trunc:
589 case Instruction::FPTrunc:
590 case Instruction::BitCast:
591 case Instruction::ShuffleVector:
592 return TTI->getCastInstrCost(Opcode, T1, T2);
593 }
594
595 return 1;
596 }
597
598 // This determines the relative offset of two loads or stores, returning
599 // true if the offset could be determined to be some constant value.
600 // For example, if OffsetInElmts == 1, then J accesses the memory directly
601 // after I; if OffsetInElmts == -1 then I accesses the memory
602 // directly after J.
603 bool getPairPtrInfo(Instruction *I, Instruction *J,
604 Value *&IPtr, Value *&JPtr, unsigned &IAlignment, unsigned &JAlignment,
605 unsigned &IAddressSpace, unsigned &JAddressSpace,
606 int64_t &OffsetInElmts, bool ComputeOffset = true) {
607 OffsetInElmts = 0;
608 if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
609 LoadInst *LJ = cast<LoadInst>(J);
610 IPtr = LI->getPointerOperand();
611 JPtr = LJ->getPointerOperand();
612 IAlignment = LI->getAlignment();
613 JAlignment = LJ->getAlignment();
614 IAddressSpace = LI->getPointerAddressSpace();
615 JAddressSpace = LJ->getPointerAddressSpace();
616 } else {
617 StoreInst *SI = cast<StoreInst>(I), *SJ = cast<StoreInst>(J);
618 IPtr = SI->getPointerOperand();
619 JPtr = SJ->getPointerOperand();
620 IAlignment = SI->getAlignment();
621 JAlignment = SJ->getAlignment();
622 IAddressSpace = SI->getPointerAddressSpace();
623 JAddressSpace = SJ->getPointerAddressSpace();
624 }
625
626 if (!ComputeOffset)
627 return true;
628
629 const SCEV *IPtrSCEV = SE->getSCEV(IPtr);
630 const SCEV *JPtrSCEV = SE->getSCEV(JPtr);
631
632 // If this is a trivial offset, then we'll get something like
633 // 1*sizeof(type). With target data, which we need anyway, this will get
634 // constant folded into a number.
635 const SCEV *OffsetSCEV = SE->getMinusSCEV(JPtrSCEV, IPtrSCEV);
636 if (const SCEVConstant *ConstOffSCEV =
637 dyn_cast<SCEVConstant>(OffsetSCEV)) {
638 ConstantInt *IntOff = ConstOffSCEV->getValue();
639 int64_t Offset = IntOff->getSExtValue();
640
641 Type *VTy = IPtr->getType()->getPointerElementType();
642 int64_t VTyTSS = (int64_t) DL->getTypeStoreSize(VTy);
643
644 Type *VTy2 = JPtr->getType()->getPointerElementType();
645 if (VTy != VTy2 && Offset < 0) {
646 int64_t VTy2TSS = (int64_t) DL->getTypeStoreSize(VTy2);
647 OffsetInElmts = Offset/VTy2TSS;
648 return (abs64(Offset) % VTy2TSS) == 0;
649 }
650
651 OffsetInElmts = Offset/VTyTSS;
652 return (abs64(Offset) % VTyTSS) == 0;
653 }
654
655 return false;
656 }
657
658 // Returns true if the provided CallInst represents an intrinsic that can
659 // be vectorized.
660 bool isVectorizableIntrinsic(CallInst* I) {
661 Function *F = I->getCalledFunction();
662 if (!F) return false;
663
664 Intrinsic::ID IID = (Intrinsic::ID) F->getIntrinsicID();
665 if (!IID) return false;
666
667 switch(IID) {
668 default:
669 return false;
670 case Intrinsic::sqrt:
671 case Intrinsic::powi:
672 case Intrinsic::sin:
673 case Intrinsic::cos:
674 case Intrinsic::log:
675 case Intrinsic::log2:
676 case Intrinsic::log10:
677 case Intrinsic::exp:
678 case Intrinsic::exp2:
679 case Intrinsic::pow:
680 case Intrinsic::round:
681 case Intrinsic::copysign:
682 case Intrinsic::ceil:
683 case Intrinsic::nearbyint:
684 case Intrinsic::rint:
685 case Intrinsic::trunc:
686 case Intrinsic::floor:
687 case Intrinsic::fabs:
688 case Intrinsic::minnum:
689 case Intrinsic::maxnum:
690 return Config.VectorizeMath;
691 case Intrinsic::bswap:
692 case Intrinsic::ctpop:
693 case Intrinsic::ctlz:
694 case Intrinsic::cttz:
695 return Config.VectorizeBitManipulations;
696 case Intrinsic::fma:
697 case Intrinsic::fmuladd:
698 return Config.VectorizeFMA;
699 }
700 }
701
702 bool isPureIEChain(InsertElementInst *IE) {
703 InsertElementInst *IENext = IE;
704 do {
705 if (!isa<UndefValue>(IENext->getOperand(0)) &&
706 !isa<InsertElementInst>(IENext->getOperand(0))) {
707 return false;
708 }
709 } while ((IENext =
710 dyn_cast<InsertElementInst>(IENext->getOperand(0))));
711
712 return true;
713 }
714 };
715
716 // This function implements one vectorization iteration on the provided
717 // basic block. It returns true if the block is changed.
718 bool BBVectorize::vectorizePairs(BasicBlock &BB, bool NonPow2Len) {
719 bool ShouldContinue;
720 BasicBlock::iterator Start = BB.getFirstInsertionPt();
721
722 std::vector<Value *> AllPairableInsts;
723 DenseMap<Value *, Value *> AllChosenPairs;
724 DenseSet<ValuePair> AllFixedOrderPairs;
725 DenseMap<VPPair, unsigned> AllPairConnectionTypes;
726 DenseMap<ValuePair, std::vector<ValuePair> > AllConnectedPairs,
727 AllConnectedPairDeps;
728
729 do {
730 std::vector<Value *> PairableInsts;
731 DenseMap<Value *, std::vector<Value *> > CandidatePairs;
732 DenseSet<ValuePair> FixedOrderPairs;
733 DenseMap<ValuePair, int> CandidatePairCostSavings;
734 ShouldContinue = getCandidatePairs(BB, Start, CandidatePairs,
735 FixedOrderPairs,
736 CandidatePairCostSavings,
737 PairableInsts, NonPow2Len);
738 if (PairableInsts.empty()) continue;
739
740 // Build the candidate pair set for faster lookups.
741 DenseSet<ValuePair> CandidatePairsSet;
742 for (DenseMap<Value *, std::vector<Value *> >::iterator I =
743 CandidatePairs.begin(), E = CandidatePairs.end(); I != E; ++I)
744 for (std::vector<Value *>::iterator J = I->second.begin(),
745 JE = I->second.end(); J != JE; ++J)
746 CandidatePairsSet.insert(ValuePair(I->first, *J));
747
748 // Now we have a map of all of the pairable instructions and we need to
749 // select the best possible pairing. A good pairing is one such that the
750 // users of the pair are also paired. This defines a (directed) forest
751 // over the pairs such that two pairs are connected iff the second pair
752 // uses the first.
753
754 // Note that it only matters that both members of the second pair use some
755 // element of the first pair (to allow for splatting).
756
757 DenseMap<ValuePair, std::vector<ValuePair> > ConnectedPairs,
758 ConnectedPairDeps;
759 DenseMap<VPPair, unsigned> PairConnectionTypes;
760 computeConnectedPairs(CandidatePairs, CandidatePairsSet,
761 PairableInsts, ConnectedPairs, PairConnectionTypes);
762 if (ConnectedPairs.empty()) continue;
763
764 for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator
765 I = ConnectedPairs.begin(), IE = ConnectedPairs.end();
766 I != IE; ++I)
767 for (std::vector<ValuePair>::iterator J = I->second.begin(),
768 JE = I->second.end(); J != JE; ++J)
769 ConnectedPairDeps[*J].push_back(I->first);
770
771 // Build the pairable-instruction dependency map
772 DenseSet<ValuePair> PairableInstUsers;
773 buildDepMap(BB, CandidatePairs, PairableInsts, PairableInstUsers);
774
775 // There is now a graph of the connected pairs. For each variable, pick
776 // the pairing with the largest dag meeting the depth requirement on at
777 // least one branch. Then select all pairings that are part of that dag
778 // and remove them from the list of available pairings and pairable
779 // variables.
780
781 DenseMap<Value *, Value *> ChosenPairs;
782 choosePairs(CandidatePairs, CandidatePairsSet,
783 CandidatePairCostSavings,
784 PairableInsts, FixedOrderPairs, PairConnectionTypes,
785 ConnectedPairs, ConnectedPairDeps,
786 PairableInstUsers, ChosenPairs);
787
788 if (ChosenPairs.empty()) continue;
789 AllPairableInsts.insert(AllPairableInsts.end(), PairableInsts.begin(),
790 PairableInsts.end());
791 AllChosenPairs.insert(ChosenPairs.begin(), ChosenPairs.end());
792
793 // Only for the chosen pairs, propagate information on fixed-order pairs,
794 // pair connections, and their types to the data structures used by the
795 // pair fusion procedures.
796 for (DenseMap<Value *, Value *>::iterator I = ChosenPairs.begin(),
797 IE = ChosenPairs.end(); I != IE; ++I) {
798 if (FixedOrderPairs.count(*I))
799 AllFixedOrderPairs.insert(*I);
800 else if (FixedOrderPairs.count(ValuePair(I->second, I->first)))
801 AllFixedOrderPairs.insert(ValuePair(I->second, I->first));
802
803 for (DenseMap<Value *, Value *>::iterator J = ChosenPairs.begin();
804 J != IE; ++J) {
805 DenseMap<VPPair, unsigned>::iterator K =
806 PairConnectionTypes.find(VPPair(*I, *J));
807 if (K != PairConnectionTypes.end()) {
808 AllPairConnectionTypes.insert(*K);
809 } else {
810 K = PairConnectionTypes.find(VPPair(*J, *I));
811 if (K != PairConnectionTypes.end())
812 AllPairConnectionTypes.insert(*K);
813 }
814 }
815 }
816
817 for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator
818 I = ConnectedPairs.begin(), IE = ConnectedPairs.end();
819 I != IE; ++I)
820 for (std::vector<ValuePair>::iterator J = I->second.begin(),
821 JE = I->second.end(); J != JE; ++J)
822 if (AllPairConnectionTypes.count(VPPair(I->first, *J))) {
823 AllConnectedPairs[I->first].push_back(*J);
824 AllConnectedPairDeps[*J].push_back(I->first);
825 }
826 } while (ShouldContinue);
827
828 if (AllChosenPairs.empty()) return false;
829 NumFusedOps += AllChosenPairs.size();
830
831 // A set of pairs has now been selected. It is now necessary to replace the
832 // paired instructions with vector instructions. For this procedure each
833 // operand must be replaced with a vector operand. This vector is formed
834 // by using build_vector on the old operands. The replaced values are then
835 // replaced with a vector_extract on the result. Subsequent optimization
836 // passes should coalesce the build/extract combinations.
837
838 fuseChosenPairs(BB, AllPairableInsts, AllChosenPairs, AllFixedOrderPairs,
839 AllPairConnectionTypes,
840 AllConnectedPairs, AllConnectedPairDeps);
841
842 // It is important to cleanup here so that future iterations of this
843 // function have less work to do.
844 (void) SimplifyInstructionsInBlock(&BB, DL, AA->getTargetLibraryInfo());
845 return true;
846 }
847
848 // This function returns true if the provided instruction is capable of being
849 // fused into a vector instruction. This determination is based only on the
850 // type and other attributes of the instruction.
851 bool BBVectorize::isInstVectorizable(Instruction *I,
852 bool &IsSimpleLoadStore) {
853 IsSimpleLoadStore = false;
854
855 if (CallInst *C = dyn_cast<CallInst>(I)) {
856 if (!isVectorizableIntrinsic(C))
857 return false;
858 } else if (LoadInst *L = dyn_cast<LoadInst>(I)) {
859 // Vectorize simple loads if possbile:
860 IsSimpleLoadStore = L->isSimple();
861 if (!IsSimpleLoadStore || !Config.VectorizeMemOps)
862 return false;
863 } else if (StoreInst *S = dyn_cast<StoreInst>(I)) {
864 // Vectorize simple stores if possbile:
865 IsSimpleLoadStore = S->isSimple();
866 if (!IsSimpleLoadStore || !Config.VectorizeMemOps)
867 return false;
868 } else if (CastInst *C = dyn_cast<CastInst>(I)) {
869 // We can vectorize casts, but not casts of pointer types, etc.
870 if (!Config.VectorizeCasts)
871 return false;
872
873 Type *SrcTy = C->getSrcTy();
874 if (!SrcTy->isSingleValueType())
875 return false;
876
877 Type *DestTy = C->getDestTy();
878 if (!DestTy->isSingleValueType())
879 return false;
880 } else if (isa<SelectInst>(I)) {
881 if (!Config.VectorizeSelect)
882 return false;
883 } else if (isa<CmpInst>(I)) {
884 if (!Config.VectorizeCmp)
885 return false;
886 } else if (GetElementPtrInst *G = dyn_cast<GetElementPtrInst>(I)) {
887 if (!Config.VectorizeGEP)
888 return false;
889
890 // Currently, vector GEPs exist only with one index.
891 if (G->getNumIndices() != 1)
892 return false;
893 } else if (!(I->isBinaryOp() || isa<ShuffleVectorInst>(I) ||
894 isa<ExtractElementInst>(I) || isa<InsertElementInst>(I))) {
895 return false;
896 }
897
898 // We can't vectorize memory operations without target data
899 if (!DL && IsSimpleLoadStore)
900 return false;
901
902 Type *T1, *T2;
903 getInstructionTypes(I, T1, T2);
904
905 // Not every type can be vectorized...
906 if (!(VectorType::isValidElementType(T1) || T1->isVectorTy()) ||
907 !(VectorType::isValidElementType(T2) || T2->isVectorTy()))
908 return false;
909
910 if (T1->getScalarSizeInBits() == 1) {
911 if (!Config.VectorizeBools)
912 return false;
913 } else {
914 if (!Config.VectorizeInts && T1->isIntOrIntVectorTy())
915 return false;
916 }
917
918 if (T2->getScalarSizeInBits() == 1) {
919 if (!Config.VectorizeBools)
920 return false;
921 } else {
922 if (!Config.VectorizeInts && T2->isIntOrIntVectorTy())
923 return false;
924 }
925
926 if (!Config.VectorizeFloats
927 && (T1->isFPOrFPVectorTy() || T2->isFPOrFPVectorTy()))
928 return false;
929
930 // Don't vectorize target-specific types.
931 if (T1->isX86_FP80Ty() || T1->isPPC_FP128Ty() || T1->isX86_MMXTy())
932 return false;
933 if (T2->isX86_FP80Ty() || T2->isPPC_FP128Ty() || T2->isX86_MMXTy())
934 return false;
935
936 if ((!Config.VectorizePointers || !DL) &&
937 (T1->getScalarType()->isPointerTy() ||
938 T2->getScalarType()->isPointerTy()))
939 return false;
940
941 if (!TTI && (T1->getPrimitiveSizeInBits() >= Config.VectorBits ||
942 T2->getPrimitiveSizeInBits() >= Config.VectorBits))
943 return false;
944
945 return true;
946 }
947
948 // This function returns true if the two provided instructions are compatible
949 // (meaning that they can be fused into a vector instruction). This assumes
950 // that I has already been determined to be vectorizable and that J is not
951 // in the use dag of I.
952 bool BBVectorize::areInstsCompatible(Instruction *I, Instruction *J,
953 bool IsSimpleLoadStore, bool NonPow2Len,
954 int &CostSavings, int &FixedOrder) {
955 DEBUG(if (DebugInstructionExamination) dbgs() << "BBV: looking at " << *I <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugInstructionExamination) dbgs() <<
"BBV: looking at " << *I << " <-> " <<
*J << "\n"; } } while (0)
956 " <-> " << *J << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugInstructionExamination) dbgs() <<
"BBV: looking at " << *I << " <-> " <<
*J << "\n"; } } while (0)
;
957
958 CostSavings = 0;
959 FixedOrder = 0;
960
961 // Loads and stores can be merged if they have different alignments,
962 // but are otherwise the same.
963 if (!J->isSameOperationAs(I, Instruction::CompareIgnoringAlignment |
964 (NonPow2Len ? Instruction::CompareUsingScalarTypes : 0)))
965 return false;
966
967 Type *IT1, *IT2, *JT1, *JT2;
968 getInstructionTypes(I, IT1, IT2);
969 getInstructionTypes(J, JT1, JT2);
970 unsigned MaxTypeBits = std::max(
971 IT1->getPrimitiveSizeInBits() + JT1->getPrimitiveSizeInBits(),
972 IT2->getPrimitiveSizeInBits() + JT2->getPrimitiveSizeInBits());
973 if (!TTI && MaxTypeBits > Config.VectorBits)
974 return false;
975
976 // FIXME: handle addsub-type operations!
977
978 if (IsSimpleLoadStore) {
979 Value *IPtr, *JPtr;
980 unsigned IAlignment, JAlignment, IAddressSpace, JAddressSpace;
981 int64_t OffsetInElmts = 0;
982 if (getPairPtrInfo(I, J, IPtr, JPtr, IAlignment, JAlignment,
983 IAddressSpace, JAddressSpace,
984 OffsetInElmts) && abs64(OffsetInElmts) == 1) {
985 FixedOrder = (int) OffsetInElmts;
986 unsigned BottomAlignment = IAlignment;
987 if (OffsetInElmts < 0) BottomAlignment = JAlignment;
988
989 Type *aTypeI = isa<StoreInst>(I) ?
990 cast<StoreInst>(I)->getValueOperand()->getType() : I->getType();
991 Type *aTypeJ = isa<StoreInst>(J) ?
992 cast<StoreInst>(J)->getValueOperand()->getType() : J->getType();
993 Type *VType = getVecTypeForPair(aTypeI, aTypeJ);
994
995 if (Config.AlignedOnly) {
996 // An aligned load or store is possible only if the instruction
997 // with the lower offset has an alignment suitable for the
998 // vector type.
999
1000 unsigned VecAlignment = DL->getPrefTypeAlignment(VType);
1001 if (BottomAlignment < VecAlignment)
1002 return false;
1003 }
1004
1005 if (TTI) {
1006 unsigned ICost = TTI->getMemoryOpCost(I->getOpcode(), aTypeI,
1007 IAlignment, IAddressSpace);
1008 unsigned JCost = TTI->getMemoryOpCost(J->getOpcode(), aTypeJ,
1009 JAlignment, JAddressSpace);
1010 unsigned VCost = TTI->getMemoryOpCost(I->getOpcode(), VType,
1011 BottomAlignment,
1012 IAddressSpace);
1013
1014 ICost += TTI->getAddressComputationCost(aTypeI);
1015 JCost += TTI->getAddressComputationCost(aTypeJ);
1016 VCost += TTI->getAddressComputationCost(VType);
1017
1018 if (VCost > ICost + JCost)
1019 return false;
1020
1021 // We don't want to fuse to a type that will be split, even
1022 // if the two input types will also be split and there is no other
1023 // associated cost.
1024 unsigned VParts = TTI->getNumberOfParts(VType);
1025 if (VParts > 1)
1026 return false;
1027 else if (!VParts && VCost == ICost + JCost)
1028 return false;
1029
1030 CostSavings = ICost + JCost - VCost;
1031 }
1032 } else {
1033 return false;
1034 }
1035 } else if (TTI) {
1036 unsigned ICost = getInstrCost(I->getOpcode(), IT1, IT2);
1037 unsigned JCost = getInstrCost(J->getOpcode(), JT1, JT2);
1038 Type *VT1 = getVecTypeForPair(IT1, JT1),
1039 *VT2 = getVecTypeForPair(IT2, JT2);
1040 TargetTransformInfo::OperandValueKind Op1VK =
1041 TargetTransformInfo::OK_AnyValue;
1042 TargetTransformInfo::OperandValueKind Op2VK =
1043 TargetTransformInfo::OK_AnyValue;
1044
1045 // On some targets (example X86) the cost of a vector shift may vary
1046 // depending on whether the second operand is a Uniform or
1047 // NonUniform Constant.
1048 switch (I->getOpcode()) {
1049 default : break;
1050 case Instruction::Shl:
1051 case Instruction::LShr:
1052 case Instruction::AShr:
1053
1054 // If both I and J are scalar shifts by constant, then the
1055 // merged vector shift count would be either a constant splat value
1056 // or a non-uniform vector of constants.
1057 if (ConstantInt *CII = dyn_cast<ConstantInt>(I->getOperand(1))) {
1058 if (ConstantInt *CIJ = dyn_cast<ConstantInt>(J->getOperand(1)))
1059 Op2VK = CII == CIJ ? TargetTransformInfo::OK_UniformConstantValue :
1060 TargetTransformInfo::OK_NonUniformConstantValue;
1061 } else {
1062 // Check for a splat of a constant or for a non uniform vector
1063 // of constants.
1064 Value *IOp = I->getOperand(1);
1065 Value *JOp = J->getOperand(1);
1066 if ((isa<ConstantVector>(IOp) || isa<ConstantDataVector>(IOp)) &&
1067 (isa<ConstantVector>(JOp) || isa<ConstantDataVector>(JOp))) {
1068 Op2VK = TargetTransformInfo::OK_NonUniformConstantValue;
1069 Constant *SplatValue = cast<Constant>(IOp)->getSplatValue();
1070 if (SplatValue != nullptr &&
1071 SplatValue == cast<Constant>(JOp)->getSplatValue())
1072 Op2VK = TargetTransformInfo::OK_UniformConstantValue;
1073 }
1074 }
1075 }
1076
1077 // Note that this procedure is incorrect for insert and extract element
1078 // instructions (because combining these often results in a shuffle),
1079 // but this cost is ignored (because insert and extract element
1080 // instructions are assigned a zero depth factor and are not really
1081 // fused in general).
1082 unsigned VCost = getInstrCost(I->getOpcode(), VT1, VT2, Op1VK, Op2VK);
1083
1084 if (VCost > ICost + JCost)
1085 return false;
1086
1087 // We don't want to fuse to a type that will be split, even
1088 // if the two input types will also be split and there is no other
1089 // associated cost.
1090 unsigned VParts1 = TTI->getNumberOfParts(VT1),
1091 VParts2 = TTI->getNumberOfParts(VT2);
1092 if (VParts1 > 1 || VParts2 > 1)
1093 return false;
1094 else if ((!VParts1 || !VParts2) && VCost == ICost + JCost)
1095 return false;
1096
1097 CostSavings = ICost + JCost - VCost;
1098 }
1099
1100 // The powi,ctlz,cttz intrinsics are special because only the first
1101 // argument is vectorized, the second arguments must be equal.
1102 CallInst *CI = dyn_cast<CallInst>(I);
1103 Function *FI;
1104 if (CI && (FI = CI->getCalledFunction())) {
1105 Intrinsic::ID IID = (Intrinsic::ID) FI->getIntrinsicID();
1106 if (IID == Intrinsic::powi || IID == Intrinsic::ctlz ||
1107 IID == Intrinsic::cttz) {
1108 Value *A1I = CI->getArgOperand(1),
1109 *A1J = cast<CallInst>(J)->getArgOperand(1);
1110 const SCEV *A1ISCEV = SE->getSCEV(A1I),
1111 *A1JSCEV = SE->getSCEV(A1J);
1112 return (A1ISCEV == A1JSCEV);
1113 }
1114
1115 if (IID && TTI) {
1116 SmallVector<Type*, 4> Tys;
1117 for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i)
1118 Tys.push_back(CI->getArgOperand(i)->getType());
1119 unsigned ICost = TTI->getIntrinsicInstrCost(IID, IT1, Tys);
1120
1121 Tys.clear();
1122 CallInst *CJ = cast<CallInst>(J);
1123 for (unsigned i = 0, ie = CJ->getNumArgOperands(); i != ie; ++i)
1124 Tys.push_back(CJ->getArgOperand(i)->getType());
1125 unsigned JCost = TTI->getIntrinsicInstrCost(IID, JT1, Tys);
1126
1127 Tys.clear();
1128 assert(CI->getNumArgOperands() == CJ->getNumArgOperands() &&((CI->getNumArgOperands() == CJ->getNumArgOperands() &&
"Intrinsic argument counts differ") ? static_cast<void>
(0) : __assert_fail ("CI->getNumArgOperands() == CJ->getNumArgOperands() && \"Intrinsic argument counts differ\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 1129, __PRETTY_FUNCTION__))
1129 "Intrinsic argument counts differ")((CI->getNumArgOperands() == CJ->getNumArgOperands() &&
"Intrinsic argument counts differ") ? static_cast<void>
(0) : __assert_fail ("CI->getNumArgOperands() == CJ->getNumArgOperands() && \"Intrinsic argument counts differ\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 1129, __PRETTY_FUNCTION__))
;
1130 for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i) {
1131 if ((IID == Intrinsic::powi || IID == Intrinsic::ctlz ||
1132 IID == Intrinsic::cttz) && i == 1)
1133 Tys.push_back(CI->getArgOperand(i)->getType());
1134 else
1135 Tys.push_back(getVecTypeForPair(CI->getArgOperand(i)->getType(),
1136 CJ->getArgOperand(i)->getType()));
1137 }
1138
1139 Type *RetTy = getVecTypeForPair(IT1, JT1);
1140 unsigned VCost = TTI->getIntrinsicInstrCost(IID, RetTy, Tys);
1141
1142 if (VCost > ICost + JCost)
1143 return false;
1144
1145 // We don't want to fuse to a type that will be split, even
1146 // if the two input types will also be split and there is no other
1147 // associated cost.
1148 unsigned RetParts = TTI->getNumberOfParts(RetTy);
1149 if (RetParts > 1)
1150 return false;
1151 else if (!RetParts && VCost == ICost + JCost)
1152 return false;
1153
1154 for (unsigned i = 0, ie = CI->getNumArgOperands(); i != ie; ++i) {
1155 if (!Tys[i]->isVectorTy())
1156 continue;
1157
1158 unsigned NumParts = TTI->getNumberOfParts(Tys[i]);
1159 if (NumParts > 1)
1160 return false;
1161 else if (!NumParts && VCost == ICost + JCost)
1162 return false;
1163 }
1164
1165 CostSavings = ICost + JCost - VCost;
1166 }
1167 }
1168
1169 return true;
1170 }
1171
1172 // Figure out whether or not J uses I and update the users and write-set
1173 // structures associated with I. Specifically, Users represents the set of
1174 // instructions that depend on I. WriteSet represents the set
1175 // of memory locations that are dependent on I. If UpdateUsers is true,
1176 // and J uses I, then Users is updated to contain J and WriteSet is updated
1177 // to contain any memory locations to which J writes. The function returns
1178 // true if J uses I. By default, alias analysis is used to determine
1179 // whether J reads from memory that overlaps with a location in WriteSet.
1180 // If LoadMoveSet is not null, then it is a previously-computed map
1181 // where the key is the memory-based user instruction and the value is
1182 // the instruction to be compared with I. So, if LoadMoveSet is provided,
1183 // then the alias analysis is not used. This is necessary because this
1184 // function is called during the process of moving instructions during
1185 // vectorization and the results of the alias analysis are not stable during
1186 // that process.
1187 bool BBVectorize::trackUsesOfI(DenseSet<Value *> &Users,
1188 AliasSetTracker &WriteSet, Instruction *I,
1189 Instruction *J, bool UpdateUsers,
1190 DenseSet<ValuePair> *LoadMoveSetPairs) {
1191 bool UsesI = false;
1192
1193 // This instruction may already be marked as a user due, for example, to
1194 // being a member of a selected pair.
1195 if (Users.count(J))
1196 UsesI = true;
1197
1198 if (!UsesI)
1199 for (User::op_iterator JU = J->op_begin(), JE = J->op_end();
1200 JU != JE; ++JU) {
1201 Value *V = *JU;
1202 if (I == V || Users.count(V)) {
1203 UsesI = true;
1204 break;
1205 }
1206 }
1207 if (!UsesI && J->mayReadFromMemory()) {
1208 if (LoadMoveSetPairs) {
1209 UsesI = LoadMoveSetPairs->count(ValuePair(J, I));
1210 } else {
1211 for (AliasSetTracker::iterator W = WriteSet.begin(),
1212 WE = WriteSet.end(); W != WE; ++W) {
1213 if (W->aliasesUnknownInst(J, *AA)) {
1214 UsesI = true;
1215 break;
1216 }
1217 }
1218 }
1219 }
1220
1221 if (UsesI && UpdateUsers) {
1222 if (J->mayWriteToMemory()) WriteSet.add(J);
1223 Users.insert(J);
1224 }
1225
1226 return UsesI;
1227 }
1228
1229 // This function iterates over all instruction pairs in the provided
1230 // basic block and collects all candidate pairs for vectorization.
1231 bool BBVectorize::getCandidatePairs(BasicBlock &BB,
1232 BasicBlock::iterator &Start,
1233 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
1234 DenseSet<ValuePair> &FixedOrderPairs,
1235 DenseMap<ValuePair, int> &CandidatePairCostSavings,
1236 std::vector<Value *> &PairableInsts, bool NonPow2Len) {
1237 size_t TotalPairs = 0;
1238 BasicBlock::iterator E = BB.end();
1239 if (Start == E) return false;
1240
1241 bool ShouldContinue = false, IAfterStart = false;
1242 for (BasicBlock::iterator I = Start++; I != E; ++I) {
1243 if (I == Start) IAfterStart = true;
1244
1245 bool IsSimpleLoadStore;
1246 if (!isInstVectorizable(I, IsSimpleLoadStore)) continue;
1247
1248 // Look for an instruction with which to pair instruction *I...
1249 DenseSet<Value *> Users;
1250 AliasSetTracker WriteSet(*AA);
1251 if (I->mayWriteToMemory()) WriteSet.add(I);
1252
1253 bool JAfterStart = IAfterStart;
1254 BasicBlock::iterator J = std::next(I);
1255 for (unsigned ss = 0; J != E && ss <= Config.SearchLimit; ++J, ++ss) {
1256 if (J == Start) JAfterStart = true;
1257
1258 // Determine if J uses I, if so, exit the loop.
1259 bool UsesI = trackUsesOfI(Users, WriteSet, I, J, !Config.FastDep);
1260 if (Config.FastDep) {
1261 // Note: For this heuristic to be effective, independent operations
1262 // must tend to be intermixed. This is likely to be true from some
1263 // kinds of grouped loop unrolling (but not the generic LLVM pass),
1264 // but otherwise may require some kind of reordering pass.
1265
1266 // When using fast dependency analysis,
1267 // stop searching after first use:
1268 if (UsesI) break;
1269 } else {
1270 if (UsesI) continue;
1271 }
1272
1273 // J does not use I, and comes before the first use of I, so it can be
1274 // merged with I if the instructions are compatible.
1275 int CostSavings, FixedOrder;
1276 if (!areInstsCompatible(I, J, IsSimpleLoadStore, NonPow2Len,
1277 CostSavings, FixedOrder)) continue;
1278
1279 // J is a candidate for merging with I.
1280 if (!PairableInsts.size() ||
1281 PairableInsts[PairableInsts.size()-1] != I) {
1282 PairableInsts.push_back(I);
1283 }
1284
1285 CandidatePairs[I].push_back(J);
1286 ++TotalPairs;
1287 if (TTI)
1288 CandidatePairCostSavings.insert(ValuePairWithCost(ValuePair(I, J),
1289 CostSavings));
1290
1291 if (FixedOrder == 1)
1292 FixedOrderPairs.insert(ValuePair(I, J));
1293 else if (FixedOrder == -1)
1294 FixedOrderPairs.insert(ValuePair(J, I));
1295
1296 // The next call to this function must start after the last instruction
1297 // selected during this invocation.
1298 if (JAfterStart) {
1299 Start = std::next(J);
1300 IAfterStart = JAfterStart = false;
1301 }
1302
1303 DEBUG(if (DebugCandidateSelection) dbgs() << "BBV: candidate pair "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCandidateSelection) dbgs() <<
"BBV: candidate pair " << *I << " <-> " <<
*J << " (cost savings: " << CostSavings <<
")\n"; } } while (0)
1304 << *I << " <-> " << *J << " (cost savings: " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCandidateSelection) dbgs() <<
"BBV: candidate pair " << *I << " <-> " <<
*J << " (cost savings: " << CostSavings <<
")\n"; } } while (0)
1305 CostSavings << ")\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCandidateSelection) dbgs() <<
"BBV: candidate pair " << *I << " <-> " <<
*J << " (cost savings: " << CostSavings <<
")\n"; } } while (0)
;
1306
1307 // If we have already found too many pairs, break here and this function
1308 // will be called again starting after the last instruction selected
1309 // during this invocation.
1310 if (PairableInsts.size() >= Config.MaxInsts ||
1311 TotalPairs >= Config.MaxPairs) {
1312 ShouldContinue = true;
1313 break;
1314 }
1315 }
1316
1317 if (ShouldContinue)
1318 break;
1319 }
1320
1321 DEBUG(dbgs() << "BBV: found " << PairableInsts.size()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: found " << PairableInsts
.size() << " instructions with candidate pairs\n"; } } while
(0)
1322 << " instructions with candidate pairs\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: found " << PairableInsts
.size() << " instructions with candidate pairs\n"; } } while
(0)
;
1323
1324 return ShouldContinue;
1325 }
1326
1327 // Finds candidate pairs connected to the pair P = <PI, PJ>. This means that
1328 // it looks for pairs such that both members have an input which is an
1329 // output of PI or PJ.
1330 void BBVectorize::computePairsConnectedTo(
1331 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
1332 DenseSet<ValuePair> &CandidatePairsSet,
1333 std::vector<Value *> &PairableInsts,
1334 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
1335 DenseMap<VPPair, unsigned> &PairConnectionTypes,
1336 ValuePair P) {
1337 StoreInst *SI, *SJ;
1338
1339 // For each possible pairing for this variable, look at the uses of
1340 // the first value...
1341 for (Value::user_iterator I = P.first->user_begin(),
1342 E = P.first->user_end();
1343 I != E; ++I) {
1344 User *UI = *I;
1345 if (isa<LoadInst>(UI)) {
1346 // A pair cannot be connected to a load because the load only takes one
1347 // operand (the address) and it is a scalar even after vectorization.
1348 continue;
1349 } else if ((SI = dyn_cast<StoreInst>(UI)) &&
1350 P.first == SI->getPointerOperand()) {
1351 // Similarly, a pair cannot be connected to a store through its
1352 // pointer operand.
1353 continue;
1354 }
1355
1356 // For each use of the first variable, look for uses of the second
1357 // variable...
1358 for (User *UJ : P.second->users()) {
1359 if ((SJ = dyn_cast<StoreInst>(UJ)) &&
1360 P.second == SJ->getPointerOperand())
1361 continue;
1362
1363 // Look for <I, J>:
1364 if (CandidatePairsSet.count(ValuePair(UI, UJ))) {
1365 VPPair VP(P, ValuePair(UI, UJ));
1366 ConnectedPairs[VP.first].push_back(VP.second);
1367 PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionDirect));
1368 }
1369
1370 // Look for <J, I>:
1371 if (CandidatePairsSet.count(ValuePair(UJ, UI))) {
1372 VPPair VP(P, ValuePair(UJ, UI));
1373 ConnectedPairs[VP.first].push_back(VP.second);
1374 PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSwap));
1375 }
1376 }
1377
1378 if (Config.SplatBreaksChain) continue;
1379 // Look for cases where just the first value in the pair is used by
1380 // both members of another pair (splatting).
1381 for (Value::user_iterator J = P.first->user_begin(); J != E; ++J) {
1382 User *UJ = *J;
1383 if ((SJ = dyn_cast<StoreInst>(UJ)) &&
1384 P.first == SJ->getPointerOperand())
1385 continue;
1386
1387 if (CandidatePairsSet.count(ValuePair(UI, UJ))) {
1388 VPPair VP(P, ValuePair(UI, UJ));
1389 ConnectedPairs[VP.first].push_back(VP.second);
1390 PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSplat));
1391 }
1392 }
1393 }
1394
1395 if (Config.SplatBreaksChain) return;
1396 // Look for cases where just the second value in the pair is used by
1397 // both members of another pair (splatting).
1398 for (Value::user_iterator I = P.second->user_begin(),
1399 E = P.second->user_end();
1400 I != E; ++I) {
1401 User *UI = *I;
1402 if (isa<LoadInst>(UI))
1403 continue;
1404 else if ((SI = dyn_cast<StoreInst>(UI)) &&
1405 P.second == SI->getPointerOperand())
1406 continue;
1407
1408 for (Value::user_iterator J = P.second->user_begin(); J != E; ++J) {
1409 User *UJ = *J;
1410 if ((SJ = dyn_cast<StoreInst>(UJ)) &&
1411 P.second == SJ->getPointerOperand())
1412 continue;
1413
1414 if (CandidatePairsSet.count(ValuePair(UI, UJ))) {
1415 VPPair VP(P, ValuePair(UI, UJ));
1416 ConnectedPairs[VP.first].push_back(VP.second);
1417 PairConnectionTypes.insert(VPPairWithType(VP, PairConnectionSplat));
1418 }
1419 }
1420 }
1421 }
1422
1423 // This function figures out which pairs are connected. Two pairs are
1424 // connected if some output of the first pair forms an input to both members
1425 // of the second pair.
1426 void BBVectorize::computeConnectedPairs(
1427 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
1428 DenseSet<ValuePair> &CandidatePairsSet,
1429 std::vector<Value *> &PairableInsts,
1430 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
1431 DenseMap<VPPair, unsigned> &PairConnectionTypes) {
1432 for (std::vector<Value *>::iterator PI = PairableInsts.begin(),
1433 PE = PairableInsts.end(); PI != PE; ++PI) {
1434 DenseMap<Value *, std::vector<Value *> >::iterator PP =
1435 CandidatePairs.find(*PI);
1436 if (PP == CandidatePairs.end())
1437 continue;
1438
1439 for (std::vector<Value *>::iterator P = PP->second.begin(),
1440 E = PP->second.end(); P != E; ++P)
1441 computePairsConnectedTo(CandidatePairs, CandidatePairsSet,
1442 PairableInsts, ConnectedPairs,
1443 PairConnectionTypes, ValuePair(*PI, *P));
1444 }
1445
1446 DEBUG(size_t TotalPairs = 0;do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { size_t TotalPairs = 0; for (DenseMap<ValuePair
, std::vector<ValuePair> >::iterator I = ConnectedPairs
.begin(), IE = ConnectedPairs.end(); I != IE; ++I) TotalPairs
+= I->second.size(); dbgs() << "BBV: found " <<
TotalPairs << " pair connections.\n"; } } while (0)
1447 for (DenseMap<ValuePair, std::vector<ValuePair> >::iterator I =do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { size_t TotalPairs = 0; for (DenseMap<ValuePair
, std::vector<ValuePair> >::iterator I = ConnectedPairs
.begin(), IE = ConnectedPairs.end(); I != IE; ++I) TotalPairs
+= I->second.size(); dbgs() << "BBV: found " <<
TotalPairs << " pair connections.\n"; } } while (0)
1448 ConnectedPairs.begin(), IE = ConnectedPairs.end(); I != IE; ++I)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { size_t TotalPairs = 0; for (DenseMap<ValuePair
, std::vector<ValuePair> >::iterator I = ConnectedPairs
.begin(), IE = ConnectedPairs.end(); I != IE; ++I) TotalPairs
+= I->second.size(); dbgs() << "BBV: found " <<
TotalPairs << " pair connections.\n"; } } while (0)
1449 TotalPairs += I->second.size();do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { size_t TotalPairs = 0; for (DenseMap<ValuePair
, std::vector<ValuePair> >::iterator I = ConnectedPairs
.begin(), IE = ConnectedPairs.end(); I != IE; ++I) TotalPairs
+= I->second.size(); dbgs() << "BBV: found " <<
TotalPairs << " pair connections.\n"; } } while (0)
1450 dbgs() << "BBV: found " << TotalPairsdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { size_t TotalPairs = 0; for (DenseMap<ValuePair
, std::vector<ValuePair> >::iterator I = ConnectedPairs
.begin(), IE = ConnectedPairs.end(); I != IE; ++I) TotalPairs
+= I->second.size(); dbgs() << "BBV: found " <<
TotalPairs << " pair connections.\n"; } } while (0)
1451 << " pair connections.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { size_t TotalPairs = 0; for (DenseMap<ValuePair
, std::vector<ValuePair> >::iterator I = ConnectedPairs
.begin(), IE = ConnectedPairs.end(); I != IE; ++I) TotalPairs
+= I->second.size(); dbgs() << "BBV: found " <<
TotalPairs << " pair connections.\n"; } } while (0)
;
1452 }
1453
1454 // This function builds a set of use tuples such that <A, B> is in the set
1455 // if B is in the use dag of A. If B is in the use dag of A, then B
1456 // depends on the output of A.
1457 void BBVectorize::buildDepMap(
1458 BasicBlock &BB,
1459 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
1460 std::vector<Value *> &PairableInsts,
1461 DenseSet<ValuePair> &PairableInstUsers) {
1462 DenseSet<Value *> IsInPair;
1463 for (DenseMap<Value *, std::vector<Value *> >::iterator C =
1464 CandidatePairs.begin(), E = CandidatePairs.end(); C != E; ++C) {
1465 IsInPair.insert(C->first);
1466 IsInPair.insert(C->second.begin(), C->second.end());
1467 }
1468
1469 // Iterate through the basic block, recording all users of each
1470 // pairable instruction.
1471
1472 BasicBlock::iterator E = BB.end(), EL =
1473 BasicBlock::iterator(cast<Instruction>(PairableInsts.back()));
1474 for (BasicBlock::iterator I = BB.getFirstInsertionPt(); I != E; ++I) {
1475 if (IsInPair.find(I) == IsInPair.end()) continue;
1476
1477 DenseSet<Value *> Users;
1478 AliasSetTracker WriteSet(*AA);
1479 if (I->mayWriteToMemory()) WriteSet.add(I);
1480
1481 for (BasicBlock::iterator J = std::next(I); J != E; ++J) {
1482 (void) trackUsesOfI(Users, WriteSet, I, J);
1483
1484 if (J == EL)
1485 break;
1486 }
1487
1488 for (DenseSet<Value *>::iterator U = Users.begin(), E = Users.end();
1489 U != E; ++U) {
1490 if (IsInPair.find(*U) == IsInPair.end()) continue;
1491 PairableInstUsers.insert(ValuePair(I, *U));
1492 }
1493
1494 if (I == EL)
1495 break;
1496 }
1497 }
1498
1499 // Returns true if an input to pair P is an output of pair Q and also an
1500 // input of pair Q is an output of pair P. If this is the case, then these
1501 // two pairs cannot be simultaneously fused.
1502 bool BBVectorize::pairsConflict(ValuePair P, ValuePair Q,
1503 DenseSet<ValuePair> &PairableInstUsers,
1504 DenseMap<ValuePair, std::vector<ValuePair> > *PairableInstUserMap,
1505 DenseSet<VPPair> *PairableInstUserPairSet) {
1506 // Two pairs are in conflict if they are mutual Users of eachother.
1507 bool QUsesP = PairableInstUsers.count(ValuePair(P.first, Q.first)) ||
1508 PairableInstUsers.count(ValuePair(P.first, Q.second)) ||
1509 PairableInstUsers.count(ValuePair(P.second, Q.first)) ||
1510 PairableInstUsers.count(ValuePair(P.second, Q.second));
1511 bool PUsesQ = PairableInstUsers.count(ValuePair(Q.first, P.first)) ||
1512 PairableInstUsers.count(ValuePair(Q.first, P.second)) ||
1513 PairableInstUsers.count(ValuePair(Q.second, P.first)) ||
1514 PairableInstUsers.count(ValuePair(Q.second, P.second));
1515 if (PairableInstUserMap) {
1516 // FIXME: The expensive part of the cycle check is not so much the cycle
1517 // check itself but this edge insertion procedure. This needs some
1518 // profiling and probably a different data structure.
1519 if (PUsesQ) {
1520 if (PairableInstUserPairSet->insert(VPPair(Q, P)).second)
1521 (*PairableInstUserMap)[Q].push_back(P);
1522 }
1523 if (QUsesP) {
1524 if (PairableInstUserPairSet->insert(VPPair(P, Q)).second)
1525 (*PairableInstUserMap)[P].push_back(Q);
1526 }
1527 }
1528
1529 return (QUsesP && PUsesQ);
1530 }
1531
1532 // This function walks the use graph of current pairs to see if, starting
1533 // from P, the walk returns to P.
1534 bool BBVectorize::pairWillFormCycle(ValuePair P,
1535 DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
1536 DenseSet<ValuePair> &CurrentPairs) {
1537 DEBUG(if (DebugCycleCheck)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCycleCheck) dbgs() << "BBV: starting cycle check for : "
<< *P.first << " <-> " << *P.second <<
"\n"; } } while (0)
1538 dbgs() << "BBV: starting cycle check for : " << *P.first << " <-> "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCycleCheck) dbgs() << "BBV: starting cycle check for : "
<< *P.first << " <-> " << *P.second <<
"\n"; } } while (0)
1539 << *P.second << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCycleCheck) dbgs() << "BBV: starting cycle check for : "
<< *P.first << " <-> " << *P.second <<
"\n"; } } while (0)
;
1540 // A lookup table of visisted pairs is kept because the PairableInstUserMap
1541 // contains non-direct associations.
1542 DenseSet<ValuePair> Visited;
1543 SmallVector<ValuePair, 32> Q;
1544 // General depth-first post-order traversal:
1545 Q.push_back(P);
1546 do {
1547 ValuePair QTop = Q.pop_back_val();
1548 Visited.insert(QTop);
1549
1550 DEBUG(if (DebugCycleCheck)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCycleCheck) dbgs() << "BBV: cycle check visiting: "
<< *QTop.first << " <-> " << *QTop.second
<< "\n"; } } while (0)
1551 dbgs() << "BBV: cycle check visiting: " << *QTop.first << " <-> "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCycleCheck) dbgs() << "BBV: cycle check visiting: "
<< *QTop.first << " <-> " << *QTop.second
<< "\n"; } } while (0)
1552 << *QTop.second << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugCycleCheck) dbgs() << "BBV: cycle check visiting: "
<< *QTop.first << " <-> " << *QTop.second
<< "\n"; } } while (0)
;
1553 DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ =
1554 PairableInstUserMap.find(QTop);
1555 if (QQ == PairableInstUserMap.end())
1556 continue;
1557
1558 for (std::vector<ValuePair>::iterator C = QQ->second.begin(),
1559 CE = QQ->second.end(); C != CE; ++C) {
1560 if (*C == P) {
1561 DEBUG(dbgs()do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: rejected to prevent non-trivial cycle formation: "
<< QTop.first << " <-> " << C->second
<< "\n"; } } while (0)
1562 << "BBV: rejected to prevent non-trivial cycle formation: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: rejected to prevent non-trivial cycle formation: "
<< QTop.first << " <-> " << C->second
<< "\n"; } } while (0)
1563 << QTop.first << " <-> " << C->second << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: rejected to prevent non-trivial cycle formation: "
<< QTop.first << " <-> " << C->second
<< "\n"; } } while (0)
;
1564 return true;
1565 }
1566
1567 if (CurrentPairs.count(*C) && !Visited.count(*C))
1568 Q.push_back(*C);
1569 }
1570 } while (!Q.empty());
1571
1572 return false;
1573 }
1574
1575 // This function builds the initial dag of connected pairs with the
1576 // pair J at the root.
1577 void BBVectorize::buildInitialDAGFor(
1578 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
1579 DenseSet<ValuePair> &CandidatePairsSet,
1580 std::vector<Value *> &PairableInsts,
1581 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
1582 DenseSet<ValuePair> &PairableInstUsers,
1583 DenseMap<Value *, Value *> &ChosenPairs,
1584 DenseMap<ValuePair, size_t> &DAG, ValuePair J) {
1585 // Each of these pairs is viewed as the root node of a DAG. The DAG
1586 // is then walked (depth-first). As this happens, we keep track of
1587 // the pairs that compose the DAG and the maximum depth of the DAG.
1588 SmallVector<ValuePairWithDepth, 32> Q;
1589 // General depth-first post-order traversal:
1590 Q.push_back(ValuePairWithDepth(J, getDepthFactor(J.first)));
1591 do {
1592 ValuePairWithDepth QTop = Q.back();
1593
1594 // Push each child onto the queue:
1595 bool MoreChildren = false;
1596 size_t MaxChildDepth = QTop.second;
1597 DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ =
1598 ConnectedPairs.find(QTop.first);
1599 if (QQ != ConnectedPairs.end())
1600 for (std::vector<ValuePair>::iterator k = QQ->second.begin(),
1601 ke = QQ->second.end(); k != ke; ++k) {
1602 // Make sure that this child pair is still a candidate:
1603 if (CandidatePairsSet.count(*k)) {
1604 DenseMap<ValuePair, size_t>::iterator C = DAG.find(*k);
1605 if (C == DAG.end()) {
1606 size_t d = getDepthFactor(k->first);
1607 Q.push_back(ValuePairWithDepth(*k, QTop.second+d));
1608 MoreChildren = true;
1609 } else {
1610 MaxChildDepth = std::max(MaxChildDepth, C->second);
1611 }
1612 }
1613 }
1614
1615 if (!MoreChildren) {
1616 // Record the current pair as part of the DAG:
1617 DAG.insert(ValuePairWithDepth(QTop.first, MaxChildDepth));
1618 Q.pop_back();
1619 }
1620 } while (!Q.empty());
1621 }
1622
1623 // Given some initial dag, prune it by removing conflicting pairs (pairs
1624 // that cannot be simultaneously chosen for vectorization).
1625 void BBVectorize::pruneDAGFor(
1626 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
1627 std::vector<Value *> &PairableInsts,
1628 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
1629 DenseSet<ValuePair> &PairableInstUsers,
1630 DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
1631 DenseSet<VPPair> &PairableInstUserPairSet,
1632 DenseMap<Value *, Value *> &ChosenPairs,
1633 DenseMap<ValuePair, size_t> &DAG,
1634 DenseSet<ValuePair> &PrunedDAG, ValuePair J,
1635 bool UseCycleCheck) {
1636 SmallVector<ValuePairWithDepth, 32> Q;
1637 // General depth-first post-order traversal:
1638 Q.push_back(ValuePairWithDepth(J, getDepthFactor(J.first)));
1639 do {
1640 ValuePairWithDepth QTop = Q.pop_back_val();
1641 PrunedDAG.insert(QTop.first);
1642
1643 // Visit each child, pruning as necessary...
1644 SmallVector<ValuePairWithDepth, 8> BestChildren;
1645 DenseMap<ValuePair, std::vector<ValuePair> >::iterator QQ =
1646 ConnectedPairs.find(QTop.first);
1647 if (QQ == ConnectedPairs.end())
1648 continue;
1649
1650 for (std::vector<ValuePair>::iterator K = QQ->second.begin(),
1651 KE = QQ->second.end(); K != KE; ++K) {
1652 DenseMap<ValuePair, size_t>::iterator C = DAG.find(*K);
1653 if (C == DAG.end()) continue;
1654
1655 // This child is in the DAG, now we need to make sure it is the
1656 // best of any conflicting children. There could be multiple
1657 // conflicting children, so first, determine if we're keeping
1658 // this child, then delete conflicting children as necessary.
1659
1660 // It is also necessary to guard against pairing-induced
1661 // dependencies. Consider instructions a .. x .. y .. b
1662 // such that (a,b) are to be fused and (x,y) are to be fused
1663 // but a is an input to x and b is an output from y. This
1664 // means that y cannot be moved after b but x must be moved
1665 // after b for (a,b) to be fused. In other words, after
1666 // fusing (a,b) we have y .. a/b .. x where y is an input
1667 // to a/b and x is an output to a/b: x and y can no longer
1668 // be legally fused. To prevent this condition, we must
1669 // make sure that a child pair added to the DAG is not
1670 // both an input and output of an already-selected pair.
1671
1672 // Pairing-induced dependencies can also form from more complicated
1673 // cycles. The pair vs. pair conflicts are easy to check, and so
1674 // that is done explicitly for "fast rejection", and because for
1675 // child vs. child conflicts, we may prefer to keep the current
1676 // pair in preference to the already-selected child.
1677 DenseSet<ValuePair> CurrentPairs;
1678
1679 bool CanAdd = true;
1680 for (SmallVectorImpl<ValuePairWithDepth>::iterator C2
1681 = BestChildren.begin(), E2 = BestChildren.end();
1682 C2 != E2; ++C2) {
1683 if (C2->first.first == C->first.first ||
1684 C2->first.first == C->first.second ||
1685 C2->first.second == C->first.first ||
1686 C2->first.second == C->first.second ||
1687 pairsConflict(C2->first, C->first, PairableInstUsers,
1688 UseCycleCheck ? &PairableInstUserMap : nullptr,
1689 UseCycleCheck ? &PairableInstUserPairSet
1690 : nullptr)) {
1691 if (C2->second >= C->second) {
1692 CanAdd = false;
1693 break;
1694 }
1695
1696 CurrentPairs.insert(C2->first);
1697 }
1698 }
1699 if (!CanAdd) continue;
1700
1701 // Even worse, this child could conflict with another node already
1702 // selected for the DAG. If that is the case, ignore this child.
1703 for (DenseSet<ValuePair>::iterator T = PrunedDAG.begin(),
1704 E2 = PrunedDAG.end(); T != E2; ++T) {
1705 if (T->first == C->first.first ||
1706 T->first == C->first.second ||
1707 T->second == C->first.first ||
1708 T->second == C->first.second ||
1709 pairsConflict(*T, C->first, PairableInstUsers,
1710 UseCycleCheck ? &PairableInstUserMap : nullptr,
1711 UseCycleCheck ? &PairableInstUserPairSet
1712 : nullptr)) {
1713 CanAdd = false;
1714 break;
1715 }
1716
1717 CurrentPairs.insert(*T);
1718 }
1719 if (!CanAdd) continue;
1720
1721 // And check the queue too...
1722 for (SmallVectorImpl<ValuePairWithDepth>::iterator C2 = Q.begin(),
1723 E2 = Q.end(); C2 != E2; ++C2) {
1724 if (C2->first.first == C->first.first ||
1725 C2->first.first == C->first.second ||
1726 C2->first.second == C->first.first ||
1727 C2->first.second == C->first.second ||
1728 pairsConflict(C2->first, C->first, PairableInstUsers,
1729 UseCycleCheck ? &PairableInstUserMap : nullptr,
1730 UseCycleCheck ? &PairableInstUserPairSet
1731 : nullptr)) {
1732 CanAdd = false;
1733 break;
1734 }
1735
1736 CurrentPairs.insert(C2->first);
1737 }
1738 if (!CanAdd) continue;
1739
1740 // Last but not least, check for a conflict with any of the
1741 // already-chosen pairs.
1742 for (DenseMap<Value *, Value *>::iterator C2 =
1743 ChosenPairs.begin(), E2 = ChosenPairs.end();
1744 C2 != E2; ++C2) {
1745 if (pairsConflict(*C2, C->first, PairableInstUsers,
1746 UseCycleCheck ? &PairableInstUserMap : nullptr,
1747 UseCycleCheck ? &PairableInstUserPairSet
1748 : nullptr)) {
1749 CanAdd = false;
1750 break;
1751 }
1752
1753 CurrentPairs.insert(*C2);
1754 }
1755 if (!CanAdd) continue;
1756
1757 // To check for non-trivial cycles formed by the addition of the
1758 // current pair we've formed a list of all relevant pairs, now use a
1759 // graph walk to check for a cycle. We start from the current pair and
1760 // walk the use dag to see if we again reach the current pair. If we
1761 // do, then the current pair is rejected.
1762
1763 // FIXME: It may be more efficient to use a topological-ordering
1764 // algorithm to improve the cycle check. This should be investigated.
1765 if (UseCycleCheck &&
1766 pairWillFormCycle(C->first, PairableInstUserMap, CurrentPairs))
1767 continue;
1768
1769 // This child can be added, but we may have chosen it in preference
1770 // to an already-selected child. Check for this here, and if a
1771 // conflict is found, then remove the previously-selected child
1772 // before adding this one in its place.
1773 for (SmallVectorImpl<ValuePairWithDepth>::iterator C2
1774 = BestChildren.begin(); C2 != BestChildren.end();) {
1775 if (C2->first.first == C->first.first ||
1776 C2->first.first == C->first.second ||
1777 C2->first.second == C->first.first ||
1778 C2->first.second == C->first.second ||
1779 pairsConflict(C2->first, C->first, PairableInstUsers))
1780 C2 = BestChildren.erase(C2);
1781 else
1782 ++C2;
1783 }
1784
1785 BestChildren.push_back(ValuePairWithDepth(C->first, C->second));
1786 }
1787
1788 for (SmallVectorImpl<ValuePairWithDepth>::iterator C
1789 = BestChildren.begin(), E2 = BestChildren.end();
1790 C != E2; ++C) {
1791 size_t DepthF = getDepthFactor(C->first.first);
1792 Q.push_back(ValuePairWithDepth(C->first, QTop.second+DepthF));
1793 }
1794 } while (!Q.empty());
1795 }
1796
1797 // This function finds the best dag of mututally-compatible connected
1798 // pairs, given the choice of root pairs as an iterator range.
1799 void BBVectorize::findBestDAGFor(
1800 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
1801 DenseSet<ValuePair> &CandidatePairsSet,
1802 DenseMap<ValuePair, int> &CandidatePairCostSavings,
1803 std::vector<Value *> &PairableInsts,
1804 DenseSet<ValuePair> &FixedOrderPairs,
1805 DenseMap<VPPair, unsigned> &PairConnectionTypes,
1806 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
1807 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps,
1808 DenseSet<ValuePair> &PairableInstUsers,
1809 DenseMap<ValuePair, std::vector<ValuePair> > &PairableInstUserMap,
1810 DenseSet<VPPair> &PairableInstUserPairSet,
1811 DenseMap<Value *, Value *> &ChosenPairs,
1812 DenseSet<ValuePair> &BestDAG, size_t &BestMaxDepth,
1813 int &BestEffSize, Value *II, std::vector<Value *>&JJ,
1814 bool UseCycleCheck) {
1815 for (std::vector<Value *>::iterator J = JJ.begin(), JE = JJ.end();
1816 J != JE; ++J) {
1817 ValuePair IJ(II, *J);
1818 if (!CandidatePairsSet.count(IJ))
1819 continue;
1820
1821 // Before going any further, make sure that this pair does not
1822 // conflict with any already-selected pairs (see comment below
1823 // near the DAG pruning for more details).
1824 DenseSet<ValuePair> ChosenPairSet;
1825 bool DoesConflict = false;
1826 for (DenseMap<Value *, Value *>::iterator C = ChosenPairs.begin(),
1827 E = ChosenPairs.end(); C != E; ++C) {
1828 if (pairsConflict(*C, IJ, PairableInstUsers,
1829 UseCycleCheck ? &PairableInstUserMap : nullptr,
1830 UseCycleCheck ? &PairableInstUserPairSet : nullptr)) {
1831 DoesConflict = true;
1832 break;
1833 }
1834
1835 ChosenPairSet.insert(*C);
1836 }
1837 if (DoesConflict) continue;
1838
1839 if (UseCycleCheck &&
1840 pairWillFormCycle(IJ, PairableInstUserMap, ChosenPairSet))
1841 continue;
1842
1843 DenseMap<ValuePair, size_t> DAG;
1844 buildInitialDAGFor(CandidatePairs, CandidatePairsSet,
1845 PairableInsts, ConnectedPairs,
1846 PairableInstUsers, ChosenPairs, DAG, IJ);
1847
1848 // Because we'll keep the child with the largest depth, the largest
1849 // depth is still the same in the unpruned DAG.
1850 size_t MaxDepth = DAG.lookup(IJ);
1851
1852 DEBUG(if (DebugPairSelection) dbgs() << "BBV: found DAG for pair {"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "BBV: found DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second
<< "} of depth " << MaxDepth << " and size "
<< DAG.size() << "\n"; } } while (0)
1853 << *IJ.first << " <-> " << *IJ.second << "} of depth " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "BBV: found DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second
<< "} of depth " << MaxDepth << " and size "
<< DAG.size() << "\n"; } } while (0)
1854 MaxDepth << " and size " << DAG.size() << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "BBV: found DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second
<< "} of depth " << MaxDepth << " and size "
<< DAG.size() << "\n"; } } while (0)
;
1855
1856 // At this point the DAG has been constructed, but, may contain
1857 // contradictory children (meaning that different children of
1858 // some dag node may be attempting to fuse the same instruction).
1859 // So now we walk the dag again, in the case of a conflict,
1860 // keep only the child with the largest depth. To break a tie,
1861 // favor the first child.
1862
1863 DenseSet<ValuePair> PrunedDAG;
1864 pruneDAGFor(CandidatePairs, PairableInsts, ConnectedPairs,
1865 PairableInstUsers, PairableInstUserMap,
1866 PairableInstUserPairSet,
1867 ChosenPairs, DAG, PrunedDAG, IJ, UseCycleCheck);
1868
1869 int EffSize = 0;
1870 if (TTI) {
1871 DenseSet<Value *> PrunedDAGInstrs;
1872 for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(),
1873 E = PrunedDAG.end(); S != E; ++S) {
1874 PrunedDAGInstrs.insert(S->first);
1875 PrunedDAGInstrs.insert(S->second);
1876 }
1877
1878 // The set of pairs that have already contributed to the total cost.
1879 DenseSet<ValuePair> IncomingPairs;
1880
1881 // If the cost model were perfect, this might not be necessary; but we
1882 // need to make sure that we don't get stuck vectorizing our own
1883 // shuffle chains.
1884 bool HasNontrivialInsts = false;
1885
1886 // The node weights represent the cost savings associated with
1887 // fusing the pair of instructions.
1888 for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(),
1889 E = PrunedDAG.end(); S != E; ++S) {
1890 if (!isa<ShuffleVectorInst>(S->first) &&
1891 !isa<InsertElementInst>(S->first) &&
1892 !isa<ExtractElementInst>(S->first))
1893 HasNontrivialInsts = true;
1894
1895 bool FlipOrder = false;
1896
1897 if (getDepthFactor(S->first)) {
1898 int ESContrib = CandidatePairCostSavings.find(*S)->second;
1899 DEBUG(if (DebugPairSelection) dbgs() << "\tweight {"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tweight {"
<< *S->first << " <-> " << *S->
second << "} = " << ESContrib << "\n"; } } while
(0)
1900 << *S->first << " <-> " << *S->second << "} = " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tweight {"
<< *S->first << " <-> " << *S->
second << "} = " << ESContrib << "\n"; } } while
(0)
1901 ESContrib << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tweight {"
<< *S->first << " <-> " << *S->
second << "} = " << ESContrib << "\n"; } } while
(0)
;
1902 EffSize += ESContrib;
1903 }
1904
1905 // The edge weights contribute in a negative sense: they represent
1906 // the cost of shuffles.
1907 DenseMap<ValuePair, std::vector<ValuePair> >::iterator SS =
1908 ConnectedPairDeps.find(*S);
1909 if (SS != ConnectedPairDeps.end()) {
1910 unsigned NumDepsDirect = 0, NumDepsSwap = 0;
1911 for (std::vector<ValuePair>::iterator T = SS->second.begin(),
1912 TE = SS->second.end(); T != TE; ++T) {
1913 VPPair Q(*S, *T);
1914 if (!PrunedDAG.count(Q.second))
1915 continue;
1916 DenseMap<VPPair, unsigned>::iterator R =
1917 PairConnectionTypes.find(VPPair(Q.second, Q.first));
1918 assert(R != PairConnectionTypes.end() &&((R != PairConnectionTypes.end() && "Cannot find pair connection type"
) ? static_cast<void> (0) : __assert_fail ("R != PairConnectionTypes.end() && \"Cannot find pair connection type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 1919, __PRETTY_FUNCTION__))
1919 "Cannot find pair connection type")((R != PairConnectionTypes.end() && "Cannot find pair connection type"
) ? static_cast<void> (0) : __assert_fail ("R != PairConnectionTypes.end() && \"Cannot find pair connection type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 1919, __PRETTY_FUNCTION__))
;
1920 if (R->second == PairConnectionDirect)
1921 ++NumDepsDirect;
1922 else if (R->second == PairConnectionSwap)
1923 ++NumDepsSwap;
1924 }
1925
1926 // If there are more swaps than direct connections, then
1927 // the pair order will be flipped during fusion. So the real
1928 // number of swaps is the minimum number.
1929 FlipOrder = !FixedOrderPairs.count(*S) &&
1930 ((NumDepsSwap > NumDepsDirect) ||
1931 FixedOrderPairs.count(ValuePair(S->second, S->first)));
1932
1933 for (std::vector<ValuePair>::iterator T = SS->second.begin(),
1934 TE = SS->second.end(); T != TE; ++T) {
1935 VPPair Q(*S, *T);
1936 if (!PrunedDAG.count(Q.second))
1937 continue;
1938 DenseMap<VPPair, unsigned>::iterator R =
1939 PairConnectionTypes.find(VPPair(Q.second, Q.first));
1940 assert(R != PairConnectionTypes.end() &&((R != PairConnectionTypes.end() && "Cannot find pair connection type"
) ? static_cast<void> (0) : __assert_fail ("R != PairConnectionTypes.end() && \"Cannot find pair connection type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 1941, __PRETTY_FUNCTION__))
1941 "Cannot find pair connection type")((R != PairConnectionTypes.end() && "Cannot find pair connection type"
) ? static_cast<void> (0) : __assert_fail ("R != PairConnectionTypes.end() && \"Cannot find pair connection type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 1941, __PRETTY_FUNCTION__))
;
1942 Type *Ty1 = Q.second.first->getType(),
1943 *Ty2 = Q.second.second->getType();
1944 Type *VTy = getVecTypeForPair(Ty1, Ty2);
1945 if ((R->second == PairConnectionDirect && FlipOrder) ||
1946 (R->second == PairConnectionSwap && !FlipOrder) ||
1947 R->second == PairConnectionSplat) {
1948 int ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
1949 VTy, VTy);
1950
1951 if (VTy->getVectorNumElements() == 2) {
1952 if (R->second == PairConnectionSplat)
1953 ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
1954 TargetTransformInfo::SK_Broadcast, VTy));
1955 else
1956 ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
1957 TargetTransformInfo::SK_Reverse, VTy));
1958 }
1959
1960 DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *Q.second.first << " <-> " << *Q.
second.second << "} -> {" << *S->first <<
" <-> " << *S->second << "} = " <<
ESContrib << "\n"; } } while (0)
1961 *Q.second.first << " <-> " << *Q.second.second <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *Q.second.first << " <-> " << *Q.
second.second << "} -> {" << *S->first <<
" <-> " << *S->second << "} = " <<
ESContrib << "\n"; } } while (0)
1962 "} -> {" <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *Q.second.first << " <-> " << *Q.
second.second << "} -> {" << *S->first <<
" <-> " << *S->second << "} = " <<
ESContrib << "\n"; } } while (0)
1963 *S->first << " <-> " << *S->second << "} = " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *Q.second.first << " <-> " << *Q.
second.second << "} -> {" << *S->first <<
" <-> " << *S->second << "} = " <<
ESContrib << "\n"; } } while (0)
1964 ESContrib << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *Q.second.first << " <-> " << *Q.
second.second << "} -> {" << *S->first <<
" <-> " << *S->second << "} = " <<
ESContrib << "\n"; } } while (0)
;
1965 EffSize -= ESContrib;
1966 }
1967 }
1968 }
1969
1970 // Compute the cost of outgoing edges. We assume that edges outgoing
1971 // to shuffles, inserts or extracts can be merged, and so contribute
1972 // no additional cost.
1973 if (!S->first->getType()->isVoidTy()) {
1974 Type *Ty1 = S->first->getType(),
1975 *Ty2 = S->second->getType();
1976 Type *VTy = getVecTypeForPair(Ty1, Ty2);
1977
1978 bool NeedsExtraction = false;
1979 for (User *U : S->first->users()) {
1980 if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(U)) {
1981 // Shuffle can be folded if it has no other input
1982 if (isa<UndefValue>(SI->getOperand(1)))
1983 continue;
1984 }
1985 if (isa<ExtractElementInst>(U))
1986 continue;
1987 if (PrunedDAGInstrs.count(U))
1988 continue;
1989 NeedsExtraction = true;
1990 break;
1991 }
1992
1993 if (NeedsExtraction) {
1994 int ESContrib;
1995 if (Ty1->isVectorTy()) {
1996 ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
1997 Ty1, VTy);
1998 ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
1999 TargetTransformInfo::SK_ExtractSubvector, VTy, 0, Ty1));
2000 } else
2001 ESContrib = (int) TTI->getVectorInstrCost(
2002 Instruction::ExtractElement, VTy, 0);
2003
2004 DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *S->first << "} = " << ESContrib <<
"\n"; } } while (0)
2005 *S->first << "} = " << ESContrib << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *S->first << "} = " << ESContrib <<
"\n"; } } while (0)
;
2006 EffSize -= ESContrib;
2007 }
2008
2009 NeedsExtraction = false;
2010 for (User *U : S->second->users()) {
2011 if (ShuffleVectorInst *SI = dyn_cast<ShuffleVectorInst>(U)) {
2012 // Shuffle can be folded if it has no other input
2013 if (isa<UndefValue>(SI->getOperand(1)))
2014 continue;
2015 }
2016 if (isa<ExtractElementInst>(U))
2017 continue;
2018 if (PrunedDAGInstrs.count(U))
2019 continue;
2020 NeedsExtraction = true;
2021 break;
2022 }
2023
2024 if (NeedsExtraction) {
2025 int ESContrib;
2026 if (Ty2->isVectorTy()) {
2027 ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
2028 Ty2, VTy);
2029 ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
2030 TargetTransformInfo::SK_ExtractSubvector, VTy,
2031 Ty1->isVectorTy() ? Ty1->getVectorNumElements() : 1, Ty2));
2032 } else
2033 ESContrib = (int) TTI->getVectorInstrCost(
2034 Instruction::ExtractElement, VTy, 1);
2035 DEBUG(if (DebugPairSelection) dbgs() << "\tcost {" <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *S->second << "} = " << ESContrib <<
"\n"; } } while (0)
2036 *S->second << "} = " << ESContrib << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *S->second << "} = " << ESContrib <<
"\n"; } } while (0)
;
2037 EffSize -= ESContrib;
2038 }
2039 }
2040
2041 // Compute the cost of incoming edges.
2042 if (!isa<LoadInst>(S->first) && !isa<StoreInst>(S->first)) {
2043 Instruction *S1 = cast<Instruction>(S->first),
2044 *S2 = cast<Instruction>(S->second);
2045 for (unsigned o = 0; o < S1->getNumOperands(); ++o) {
2046 Value *O1 = S1->getOperand(o), *O2 = S2->getOperand(o);
2047
2048 // Combining constants into vector constants (or small vector
2049 // constants into larger ones are assumed free).
2050 if (isa<Constant>(O1) && isa<Constant>(O2))
2051 continue;
2052
2053 if (FlipOrder)
2054 std::swap(O1, O2);
2055
2056 ValuePair VP = ValuePair(O1, O2);
2057 ValuePair VPR = ValuePair(O2, O1);
2058
2059 // Internal edges are not handled here.
2060 if (PrunedDAG.count(VP) || PrunedDAG.count(VPR))
2061 continue;
2062
2063 Type *Ty1 = O1->getType(),
2064 *Ty2 = O2->getType();
2065 Type *VTy = getVecTypeForPair(Ty1, Ty2);
2066
2067 // Combining vector operations of the same type is also assumed
2068 // folded with other operations.
2069 if (Ty1 == Ty2) {
2070 // If both are insert elements, then both can be widened.
2071 InsertElementInst *IEO1 = dyn_cast<InsertElementInst>(O1),
2072 *IEO2 = dyn_cast<InsertElementInst>(O2);
2073 if (IEO1 && IEO2 && isPureIEChain(IEO1) && isPureIEChain(IEO2))
2074 continue;
2075 // If both are extract elements, and both have the same input
2076 // type, then they can be replaced with a shuffle
2077 ExtractElementInst *EIO1 = dyn_cast<ExtractElementInst>(O1),
2078 *EIO2 = dyn_cast<ExtractElementInst>(O2);
2079 if (EIO1 && EIO2 &&
2080 EIO1->getOperand(0)->getType() ==
2081 EIO2->getOperand(0)->getType())
2082 continue;
2083 // If both are a shuffle with equal operand types and only two
2084 // unqiue operands, then they can be replaced with a single
2085 // shuffle
2086 ShuffleVectorInst *SIO1 = dyn_cast<ShuffleVectorInst>(O1),
2087 *SIO2 = dyn_cast<ShuffleVectorInst>(O2);
2088 if (SIO1 && SIO2 &&
2089 SIO1->getOperand(0)->getType() ==
2090 SIO2->getOperand(0)->getType()) {
2091 SmallSet<Value *, 4> SIOps;
2092 SIOps.insert(SIO1->getOperand(0));
2093 SIOps.insert(SIO1->getOperand(1));
2094 SIOps.insert(SIO2->getOperand(0));
2095 SIOps.insert(SIO2->getOperand(1));
2096 if (SIOps.size() <= 2)
2097 continue;
2098 }
2099 }
2100
2101 int ESContrib;
2102 // This pair has already been formed.
2103 if (IncomingPairs.count(VP)) {
2104 continue;
2105 } else if (IncomingPairs.count(VPR)) {
2106 ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
2107 VTy, VTy);
2108
2109 if (VTy->getVectorNumElements() == 2)
2110 ESContrib = std::min(ESContrib, (int) TTI->getShuffleCost(
2111 TargetTransformInfo::SK_Reverse, VTy));
2112 } else if (!Ty1->isVectorTy() && !Ty2->isVectorTy()) {
2113 ESContrib = (int) TTI->getVectorInstrCost(
2114 Instruction::InsertElement, VTy, 0);
2115 ESContrib += (int) TTI->getVectorInstrCost(
2116 Instruction::InsertElement, VTy, 1);
2117 } else if (!Ty1->isVectorTy()) {
2118 // O1 needs to be inserted into a vector of size O2, and then
2119 // both need to be shuffled together.
2120 ESContrib = (int) TTI->getVectorInstrCost(
2121 Instruction::InsertElement, Ty2, 0);
2122 ESContrib += (int) getInstrCost(Instruction::ShuffleVector,
2123 VTy, Ty2);
2124 } else if (!Ty2->isVectorTy()) {
2125 // O2 needs to be inserted into a vector of size O1, and then
2126 // both need to be shuffled together.
2127 ESContrib = (int) TTI->getVectorInstrCost(
2128 Instruction::InsertElement, Ty1, 0);
2129 ESContrib += (int) getInstrCost(Instruction::ShuffleVector,
2130 VTy, Ty1);
2131 } else {
2132 Type *TyBig = Ty1, *TySmall = Ty2;
2133 if (Ty2->getVectorNumElements() > Ty1->getVectorNumElements())
2134 std::swap(TyBig, TySmall);
2135
2136 ESContrib = (int) getInstrCost(Instruction::ShuffleVector,
2137 VTy, TyBig);
2138 if (TyBig != TySmall)
2139 ESContrib += (int) getInstrCost(Instruction::ShuffleVector,
2140 TyBig, TySmall);
2141 }
2142
2143 DEBUG(if (DebugPairSelection) dbgs() << "\tcost {"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *O1 << " <-> " << *O2 << "} = "
<< ESContrib << "\n"; } } while (0)
2144 << *O1 << " <-> " << *O2 << "} = " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *O1 << " <-> " << *O2 << "} = "
<< ESContrib << "\n"; } } while (0)
2145 ESContrib << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tcost {"
<< *O1 << " <-> " << *O2 << "} = "
<< ESContrib << "\n"; } } while (0)
;
2146 EffSize -= ESContrib;
2147 IncomingPairs.insert(VP);
2148 }
2149 }
2150 }
2151
2152 if (!HasNontrivialInsts) {
2153 DEBUG(if (DebugPairSelection) dbgs() <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tNo non-trivial instructions in DAG;"
" override to zero effective size\n"; } } while (0)
2154 "\tNo non-trivial instructions in DAG;"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tNo non-trivial instructions in DAG;"
" override to zero effective size\n"; } } while (0)
2155 " override to zero effective size\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "\tNo non-trivial instructions in DAG;"
" override to zero effective size\n"; } } while (0)
;
2156 EffSize = 0;
2157 }
2158 } else {
2159 for (DenseSet<ValuePair>::iterator S = PrunedDAG.begin(),
2160 E = PrunedDAG.end(); S != E; ++S)
2161 EffSize += (int) getDepthFactor(S->first);
2162 }
2163
2164 DEBUG(if (DebugPairSelection)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "BBV: found pruned DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second
<< "} of depth " << MaxDepth << " and size "
<< PrunedDAG.size() << " (effective size: " <<
EffSize << ")\n"; } } while (0)
2165 dbgs() << "BBV: found pruned DAG for pair {"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "BBV: found pruned DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second
<< "} of depth " << MaxDepth << " and size "
<< PrunedDAG.size() << " (effective size: " <<
EffSize << ")\n"; } } while (0)
2166 << *IJ.first << " <-> " << *IJ.second << "} of depth " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "BBV: found pruned DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second
<< "} of depth " << MaxDepth << " and size "
<< PrunedDAG.size() << " (effective size: " <<
EffSize << ")\n"; } } while (0)
2167 MaxDepth << " and size " << PrunedDAG.size() <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "BBV: found pruned DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second
<< "} of depth " << MaxDepth << " and size "
<< PrunedDAG.size() << " (effective size: " <<
EffSize << ")\n"; } } while (0)
2168 " (effective size: " << EffSize << ")\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (DebugPairSelection) dbgs() << "BBV: found pruned DAG for pair {"
<< *IJ.first << " <-> " << *IJ.second
<< "} of depth " << MaxDepth << " and size "
<< PrunedDAG.size() << " (effective size: " <<
EffSize << ")\n"; } } while (0)
;
2169 if (((TTI && !UseChainDepthWithTI) ||
2170 MaxDepth >= Config.ReqChainDepth) &&
2171 EffSize > 0 && EffSize > BestEffSize) {
2172 BestMaxDepth = MaxDepth;
2173 BestEffSize = EffSize;
2174 BestDAG = PrunedDAG;
2175 }
2176 }
2177 }
2178
2179 // Given the list of candidate pairs, this function selects those
2180 // that will be fused into vector instructions.
2181 void BBVectorize::choosePairs(
2182 DenseMap<Value *, std::vector<Value *> > &CandidatePairs,
2183 DenseSet<ValuePair> &CandidatePairsSet,
2184 DenseMap<ValuePair, int> &CandidatePairCostSavings,
2185 std::vector<Value *> &PairableInsts,
2186 DenseSet<ValuePair> &FixedOrderPairs,
2187 DenseMap<VPPair, unsigned> &PairConnectionTypes,
2188 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
2189 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps,
2190 DenseSet<ValuePair> &PairableInstUsers,
2191 DenseMap<Value *, Value *>& ChosenPairs) {
2192 bool UseCycleCheck =
2193 CandidatePairsSet.size() <= Config.MaxCandPairsForCycleCheck;
2194
2195 DenseMap<Value *, std::vector<Value *> > CandidatePairs2;
2196 for (DenseSet<ValuePair>::iterator I = CandidatePairsSet.begin(),
2197 E = CandidatePairsSet.end(); I != E; ++I) {
2198 std::vector<Value *> &JJ = CandidatePairs2[I->second];
2199 if (JJ.empty()) JJ.reserve(32);
2200 JJ.push_back(I->first);
2201 }
2202
2203 DenseMap<ValuePair, std::vector<ValuePair> > PairableInstUserMap;
2204 DenseSet<VPPair> PairableInstUserPairSet;
2205 for (std::vector<Value *>::iterator I = PairableInsts.begin(),
2206 E = PairableInsts.end(); I != E; ++I) {
2207 // The number of possible pairings for this variable:
2208 size_t NumChoices = CandidatePairs.lookup(*I).size();
2209 if (!NumChoices) continue;
2210
2211 std::vector<Value *> &JJ = CandidatePairs[*I];
2212
2213 // The best pair to choose and its dag:
2214 size_t BestMaxDepth = 0;
2215 int BestEffSize = 0;
2216 DenseSet<ValuePair> BestDAG;
2217 findBestDAGFor(CandidatePairs, CandidatePairsSet,
2218 CandidatePairCostSavings,
2219 PairableInsts, FixedOrderPairs, PairConnectionTypes,
2220 ConnectedPairs, ConnectedPairDeps,
2221 PairableInstUsers, PairableInstUserMap,
2222 PairableInstUserPairSet, ChosenPairs,
2223 BestDAG, BestMaxDepth, BestEffSize, *I, JJ,
2224 UseCycleCheck);
2225
2226 if (BestDAG.empty())
2227 continue;
2228
2229 // A dag has been chosen (or not) at this point. If no dag was
2230 // chosen, then this instruction, I, cannot be paired (and is no longer
2231 // considered).
2232
2233 DEBUG(dbgs() << "BBV: selected pairs in the best DAG for: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: selected pairs in the best DAG for: "
<< *cast<Instruction>(*I) << "\n"; } } while
(0)
2234 << *cast<Instruction>(*I) << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: selected pairs in the best DAG for: "
<< *cast<Instruction>(*I) << "\n"; } } while
(0)
;
2235
2236 for (DenseSet<ValuePair>::iterator S = BestDAG.begin(),
2237 SE2 = BestDAG.end(); S != SE2; ++S) {
2238 // Insert the members of this dag into the list of chosen pairs.
2239 ChosenPairs.insert(ValuePair(S->first, S->second));
2240 DEBUG(dbgs() << "BBV: selected pair: " << *S->first << " <-> " <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: selected pair: " <<
*S->first << " <-> " << *S->second <<
"\n"; } } while (0)
2241 *S->second << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: selected pair: " <<
*S->first << " <-> " << *S->second <<
"\n"; } } while (0)
;
2242
2243 // Remove all candidate pairs that have values in the chosen dag.
2244 std::vector<Value *> &KK = CandidatePairs[S->first];
2245 for (std::vector<Value *>::iterator K = KK.begin(), KE = KK.end();
2246 K != KE; ++K) {
2247 if (*K == S->second)
2248 continue;
2249
2250 CandidatePairsSet.erase(ValuePair(S->first, *K));
2251 }
2252
2253 std::vector<Value *> &LL = CandidatePairs2[S->second];
2254 for (std::vector<Value *>::iterator L = LL.begin(), LE = LL.end();
2255 L != LE; ++L) {
2256 if (*L == S->first)
2257 continue;
2258
2259 CandidatePairsSet.erase(ValuePair(*L, S->second));
2260 }
2261
2262 std::vector<Value *> &MM = CandidatePairs[S->second];
2263 for (std::vector<Value *>::iterator M = MM.begin(), ME = MM.end();
2264 M != ME; ++M) {
2265 assert(*M != S->first && "Flipped pair in candidate list?")((*M != S->first && "Flipped pair in candidate list?"
) ? static_cast<void> (0) : __assert_fail ("*M != S->first && \"Flipped pair in candidate list?\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 2265, __PRETTY_FUNCTION__))
;
2266 CandidatePairsSet.erase(ValuePair(S->second, *M));
2267 }
2268
2269 std::vector<Value *> &NN = CandidatePairs2[S->first];
2270 for (std::vector<Value *>::iterator N = NN.begin(), NE = NN.end();
2271 N != NE; ++N) {
2272 assert(*N != S->second && "Flipped pair in candidate list?")((*N != S->second && "Flipped pair in candidate list?"
) ? static_cast<void> (0) : __assert_fail ("*N != S->second && \"Flipped pair in candidate list?\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 2272, __PRETTY_FUNCTION__))
;
2273 CandidatePairsSet.erase(ValuePair(*N, S->first));
2274 }
2275 }
2276 }
2277
2278 DEBUG(dbgs() << "BBV: selected " << ChosenPairs.size() << " pairs.\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: selected " <<
ChosenPairs.size() << " pairs.\n"; } } while (0)
;
2279 }
2280
2281 std::string getReplacementName(Instruction *I, bool IsInput, unsigned o,
2282 unsigned n = 0) {
2283 if (!I->hasName())
2284 return "";
2285
2286 return (I->getName() + (IsInput ? ".v.i" : ".v.r") + utostr(o) +
2287 (n > 0 ? "." + utostr(n) : "")).str();
2288 }
2289
2290 // Returns the value that is to be used as the pointer input to the vector
2291 // instruction that fuses I with J.
2292 Value *BBVectorize::getReplacementPointerInput(LLVMContext& Context,
2293 Instruction *I, Instruction *J, unsigned o) {
2294 Value *IPtr, *JPtr;
2295 unsigned IAlignment, JAlignment, IAddressSpace, JAddressSpace;
2296 int64_t OffsetInElmts;
2297
2298 // Note: the analysis might fail here, that is why the pair order has
2299 // been precomputed (OffsetInElmts must be unused here).
2300 (void) getPairPtrInfo(I, J, IPtr, JPtr, IAlignment, JAlignment,
2301 IAddressSpace, JAddressSpace,
2302 OffsetInElmts, false);
2303
2304 // The pointer value is taken to be the one with the lowest offset.
2305 Value *VPtr = IPtr;
2306
2307 Type *ArgTypeI = IPtr->getType()->getPointerElementType();
2308 Type *ArgTypeJ = JPtr->getType()->getPointerElementType();
2309 Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ);
2310 Type *VArgPtrType
2311 = PointerType::get(VArgType,
2312 IPtr->getType()->getPointerAddressSpace());
2313 return new BitCastInst(VPtr, VArgPtrType, getReplacementName(I, true, o),
2314 /* insert before */ I);
2315 }
2316
2317 void BBVectorize::fillNewShuffleMask(LLVMContext& Context, Instruction *J,
2318 unsigned MaskOffset, unsigned NumInElem,
2319 unsigned NumInElem1, unsigned IdxOffset,
2320 std::vector<Constant*> &Mask) {
2321 unsigned NumElem1 = J->getType()->getVectorNumElements();
2322 for (unsigned v = 0; v < NumElem1; ++v) {
2323 int m = cast<ShuffleVectorInst>(J)->getMaskValue(v);
2324 if (m < 0) {
2325 Mask[v+MaskOffset] = UndefValue::get(Type::getInt32Ty(Context));
2326 } else {
2327 unsigned mm = m + (int) IdxOffset;
2328 if (m >= (int) NumInElem1)
2329 mm += (int) NumInElem;
2330
2331 Mask[v+MaskOffset] =
2332 ConstantInt::get(Type::getInt32Ty(Context), mm);
2333 }
2334 }
2335 }
2336
2337 // Returns the value that is to be used as the vector-shuffle mask to the
2338 // vector instruction that fuses I with J.
2339 Value *BBVectorize::getReplacementShuffleMask(LLVMContext& Context,
2340 Instruction *I, Instruction *J) {
2341 // This is the shuffle mask. We need to append the second
2342 // mask to the first, and the numbers need to be adjusted.
2343
2344 Type *ArgTypeI = I->getType();
2345 Type *ArgTypeJ = J->getType();
2346 Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ);
2347
2348 unsigned NumElemI = ArgTypeI->getVectorNumElements();
2349
2350 // Get the total number of elements in the fused vector type.
2351 // By definition, this must equal the number of elements in
2352 // the final mask.
2353 unsigned NumElem = VArgType->getVectorNumElements();
2354 std::vector<Constant*> Mask(NumElem);
2355
2356 Type *OpTypeI = I->getOperand(0)->getType();
2357 unsigned NumInElemI = OpTypeI->getVectorNumElements();
2358 Type *OpTypeJ = J->getOperand(0)->getType();
2359 unsigned NumInElemJ = OpTypeJ->getVectorNumElements();
2360
2361 // The fused vector will be:
2362 // -----------------------------------------------------
2363 // | NumInElemI | NumInElemJ | NumInElemI | NumInElemJ |
2364 // -----------------------------------------------------
2365 // from which we'll extract NumElem total elements (where the first NumElemI
2366 // of them come from the mask in I and the remainder come from the mask
2367 // in J.
2368
2369 // For the mask from the first pair...
2370 fillNewShuffleMask(Context, I, 0, NumInElemJ, NumInElemI,
2371 0, Mask);
2372
2373 // For the mask from the second pair...
2374 fillNewShuffleMask(Context, J, NumElemI, NumInElemI, NumInElemJ,
2375 NumInElemI, Mask);
2376
2377 return ConstantVector::get(Mask);
2378 }
2379
2380 bool BBVectorize::expandIEChain(LLVMContext& Context, Instruction *I,
2381 Instruction *J, unsigned o, Value *&LOp,
2382 unsigned numElemL,
2383 Type *ArgTypeL, Type *ArgTypeH,
2384 bool IBeforeJ, unsigned IdxOff) {
2385 bool ExpandedIEChain = false;
2386 if (InsertElementInst *LIE = dyn_cast<InsertElementInst>(LOp)) {
2387 // If we have a pure insertelement chain, then this can be rewritten
2388 // into a chain that directly builds the larger type.
2389 if (isPureIEChain(LIE)) {
2390 SmallVector<Value *, 8> VectElemts(numElemL,
2391 UndefValue::get(ArgTypeL->getScalarType()));
2392 InsertElementInst *LIENext = LIE;
2393 do {
2394 unsigned Idx =
2395 cast<ConstantInt>(LIENext->getOperand(2))->getSExtValue();
2396 VectElemts[Idx] = LIENext->getOperand(1);
2397 } while ((LIENext =
2398 dyn_cast<InsertElementInst>(LIENext->getOperand(0))));
2399
2400 LIENext = nullptr;
2401 Value *LIEPrev = UndefValue::get(ArgTypeH);
2402 for (unsigned i = 0; i < numElemL; ++i) {
2403 if (isa<UndefValue>(VectElemts[i])) continue;
2404 LIENext = InsertElementInst::Create(LIEPrev, VectElemts[i],
2405 ConstantInt::get(Type::getInt32Ty(Context),
2406 i + IdxOff),
2407 getReplacementName(IBeforeJ ? I : J,
2408 true, o, i+1));
2409 LIENext->insertBefore(IBeforeJ ? J : I);
2410 LIEPrev = LIENext;
2411 }
2412
2413 LOp = LIENext ? (Value*) LIENext : UndefValue::get(ArgTypeH);
2414 ExpandedIEChain = true;
2415 }
2416 }
2417
2418 return ExpandedIEChain;
2419 }
2420
2421 static unsigned getNumScalarElements(Type *Ty) {
2422 if (VectorType *VecTy = dyn_cast<VectorType>(Ty))
2423 return VecTy->getNumElements();
2424 return 1;
2425 }
2426
2427 // Returns the value to be used as the specified operand of the vector
2428 // instruction that fuses I with J.
2429 Value *BBVectorize::getReplacementInput(LLVMContext& Context, Instruction *I,
2430 Instruction *J, unsigned o, bool IBeforeJ) {
2431 Value *CV0 = ConstantInt::get(Type::getInt32Ty(Context), 0);
2432 Value *CV1 = ConstantInt::get(Type::getInt32Ty(Context), 1);
2433
2434 // Compute the fused vector type for this operand
2435 Type *ArgTypeI = I->getOperand(o)->getType();
2436 Type *ArgTypeJ = J->getOperand(o)->getType();
2437 VectorType *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ);
2438
2439 Instruction *L = I, *H = J;
2440 Type *ArgTypeL = ArgTypeI, *ArgTypeH = ArgTypeJ;
2441
2442 unsigned numElemL = getNumScalarElements(ArgTypeL);
2443 unsigned numElemH = getNumScalarElements(ArgTypeH);
2444
2445 Value *LOp = L->getOperand(o);
2446 Value *HOp = H->getOperand(o);
2447 unsigned numElem = VArgType->getNumElements();
2448
2449 // First, we check if we can reuse the "original" vector outputs (if these
2450 // exist). We might need a shuffle.
2451 ExtractElementInst *LEE = dyn_cast<ExtractElementInst>(LOp);
2452 ExtractElementInst *HEE = dyn_cast<ExtractElementInst>(HOp);
2453 ShuffleVectorInst *LSV = dyn_cast<ShuffleVectorInst>(LOp);
2454 ShuffleVectorInst *HSV = dyn_cast<ShuffleVectorInst>(HOp);
2455
2456 // FIXME: If we're fusing shuffle instructions, then we can't apply this
2457 // optimization. The input vectors to the shuffle might be a different
2458 // length from the shuffle outputs. Unfortunately, the replacement
2459 // shuffle mask has already been formed, and the mask entries are sensitive
2460 // to the sizes of the inputs.
2461 bool IsSizeChangeShuffle =
2462 isa<ShuffleVectorInst>(L) &&
2463 (LOp->getType() != L->getType() || HOp->getType() != H->getType());
2464
2465 if ((LEE || LSV) && (HEE || HSV) && !IsSizeChangeShuffle) {
2466 // We can have at most two unique vector inputs.
2467 bool CanUseInputs = true;
2468 Value *I1, *I2 = nullptr;
2469 if (LEE) {
2470 I1 = LEE->getOperand(0);
2471 } else {
2472 I1 = LSV->getOperand(0);
2473 I2 = LSV->getOperand(1);
2474 if (I2 == I1 || isa<UndefValue>(I2))
2475 I2 = nullptr;
2476 }
2477
2478 if (HEE) {
2479 Value *I3 = HEE->getOperand(0);
2480 if (!I2 && I3 != I1)
2481 I2 = I3;
2482 else if (I3 != I1 && I3 != I2)
2483 CanUseInputs = false;
2484 } else {
2485 Value *I3 = HSV->getOperand(0);
2486 if (!I2 && I3 != I1)
2487 I2 = I3;
2488 else if (I3 != I1 && I3 != I2)
2489 CanUseInputs = false;
2490
2491 if (CanUseInputs) {
2492 Value *I4 = HSV->getOperand(1);
2493 if (!isa<UndefValue>(I4)) {
2494 if (!I2 && I4 != I1)
2495 I2 = I4;
2496 else if (I4 != I1 && I4 != I2)
2497 CanUseInputs = false;
2498 }
2499 }
2500 }
2501
2502 if (CanUseInputs) {
2503 unsigned LOpElem =
2504 cast<Instruction>(LOp)->getOperand(0)->getType()
2505 ->getVectorNumElements();
2506
2507 unsigned HOpElem =
2508 cast<Instruction>(HOp)->getOperand(0)->getType()
2509 ->getVectorNumElements();
2510
2511 // We have one or two input vectors. We need to map each index of the
2512 // operands to the index of the original vector.
2513 SmallVector<std::pair<int, int>, 8> II(numElem);
2514 for (unsigned i = 0; i < numElemL; ++i) {
2515 int Idx, INum;
2516 if (LEE) {
2517 Idx =
2518 cast<ConstantInt>(LEE->getOperand(1))->getSExtValue();
2519 INum = LEE->getOperand(0) == I1 ? 0 : 1;
2520 } else {
2521 Idx = LSV->getMaskValue(i);
2522 if (Idx < (int) LOpElem) {
2523 INum = LSV->getOperand(0) == I1 ? 0 : 1;
2524 } else {
2525 Idx -= LOpElem;
2526 INum = LSV->getOperand(1) == I1 ? 0 : 1;
2527 }
2528 }
2529
2530 II[i] = std::pair<int, int>(Idx, INum);
2531 }
2532 for (unsigned i = 0; i < numElemH; ++i) {
2533 int Idx, INum;
2534 if (HEE) {
2535 Idx =
2536 cast<ConstantInt>(HEE->getOperand(1))->getSExtValue();
2537 INum = HEE->getOperand(0) == I1 ? 0 : 1;
2538 } else {
2539 Idx = HSV->getMaskValue(i);
2540 if (Idx < (int) HOpElem) {
2541 INum = HSV->getOperand(0) == I1 ? 0 : 1;
2542 } else {
2543 Idx -= HOpElem;
2544 INum = HSV->getOperand(1) == I1 ? 0 : 1;
2545 }
2546 }
2547
2548 II[i + numElemL] = std::pair<int, int>(Idx, INum);
2549 }
2550
2551 // We now have an array which tells us from which index of which
2552 // input vector each element of the operand comes.
2553 VectorType *I1T = cast<VectorType>(I1->getType());
2554 unsigned I1Elem = I1T->getNumElements();
2555
2556 if (!I2) {
2557 // In this case there is only one underlying vector input. Check for
2558 // the trivial case where we can use the input directly.
2559 if (I1Elem == numElem) {
2560 bool ElemInOrder = true;
2561 for (unsigned i = 0; i < numElem; ++i) {
2562 if (II[i].first != (int) i && II[i].first != -1) {
2563 ElemInOrder = false;
2564 break;
2565 }
2566 }
2567
2568 if (ElemInOrder)
2569 return I1;
2570 }
2571
2572 // A shuffle is needed.
2573 std::vector<Constant *> Mask(numElem);
2574 for (unsigned i = 0; i < numElem; ++i) {
2575 int Idx = II[i].first;
2576 if (Idx == -1)
2577 Mask[i] = UndefValue::get(Type::getInt32Ty(Context));
2578 else
2579 Mask[i] = ConstantInt::get(Type::getInt32Ty(Context), Idx);
2580 }
2581
2582 Instruction *S =
2583 new ShuffleVectorInst(I1, UndefValue::get(I1T),
2584 ConstantVector::get(Mask),
2585 getReplacementName(IBeforeJ ? I : J,
2586 true, o));
2587 S->insertBefore(IBeforeJ ? J : I);
2588 return S;
2589 }
2590
2591 VectorType *I2T = cast<VectorType>(I2->getType());
2592 unsigned I2Elem = I2T->getNumElements();
2593
2594 // This input comes from two distinct vectors. The first step is to
2595 // make sure that both vectors are the same length. If not, the
2596 // smaller one will need to grow before they can be shuffled together.
2597 if (I1Elem < I2Elem) {
2598 std::vector<Constant *> Mask(I2Elem);
2599 unsigned v = 0;
2600 for (; v < I1Elem; ++v)
2601 Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
2602 for (; v < I2Elem; ++v)
2603 Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
2604
2605 Instruction *NewI1 =
2606 new ShuffleVectorInst(I1, UndefValue::get(I1T),
2607 ConstantVector::get(Mask),
2608 getReplacementName(IBeforeJ ? I : J,
2609 true, o, 1));
2610 NewI1->insertBefore(IBeforeJ ? J : I);
2611 I1 = NewI1;
2612 I1T = I2T;
2613 I1Elem = I2Elem;
2614 } else if (I1Elem > I2Elem) {
2615 std::vector<Constant *> Mask(I1Elem);
2616 unsigned v = 0;
2617 for (; v < I2Elem; ++v)
2618 Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
2619 for (; v < I1Elem; ++v)
2620 Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
2621
2622 Instruction *NewI2 =
2623 new ShuffleVectorInst(I2, UndefValue::get(I2T),
2624 ConstantVector::get(Mask),
2625 getReplacementName(IBeforeJ ? I : J,
2626 true, o, 1));
2627 NewI2->insertBefore(IBeforeJ ? J : I);
2628 I2 = NewI2;
2629 I2T = I1T;
Value stored to 'I2T' is never read
2630 I2Elem = I1Elem;
2631 }
2632
2633 // Now that both I1 and I2 are the same length we can shuffle them
2634 // together (and use the result).
2635 std::vector<Constant *> Mask(numElem);
2636 for (unsigned v = 0; v < numElem; ++v) {
2637 if (II[v].first == -1) {
2638 Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
2639 } else {
2640 int Idx = II[v].first + II[v].second * I1Elem;
2641 Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), Idx);
2642 }
2643 }
2644
2645 Instruction *NewOp =
2646 new ShuffleVectorInst(I1, I2, ConstantVector::get(Mask),
2647 getReplacementName(IBeforeJ ? I : J, true, o));
2648 NewOp->insertBefore(IBeforeJ ? J : I);
2649 return NewOp;
2650 }
2651 }
2652
2653 Type *ArgType = ArgTypeL;
2654 if (numElemL < numElemH) {
2655 if (numElemL == 1 && expandIEChain(Context, I, J, o, HOp, numElemH,
2656 ArgTypeL, VArgType, IBeforeJ, 1)) {
2657 // This is another short-circuit case: we're combining a scalar into
2658 // a vector that is formed by an IE chain. We've just expanded the IE
2659 // chain, now insert the scalar and we're done.
2660
2661 Instruction *S = InsertElementInst::Create(HOp, LOp, CV0,
2662 getReplacementName(IBeforeJ ? I : J, true, o));
2663 S->insertBefore(IBeforeJ ? J : I);
2664 return S;
2665 } else if (!expandIEChain(Context, I, J, o, LOp, numElemL, ArgTypeL,
2666 ArgTypeH, IBeforeJ)) {
2667 // The two vector inputs to the shuffle must be the same length,
2668 // so extend the smaller vector to be the same length as the larger one.
2669 Instruction *NLOp;
2670 if (numElemL > 1) {
2671
2672 std::vector<Constant *> Mask(numElemH);
2673 unsigned v = 0;
2674 for (; v < numElemL; ++v)
2675 Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
2676 for (; v < numElemH; ++v)
2677 Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
2678
2679 NLOp = new ShuffleVectorInst(LOp, UndefValue::get(ArgTypeL),
2680 ConstantVector::get(Mask),
2681 getReplacementName(IBeforeJ ? I : J,
2682 true, o, 1));
2683 } else {
2684 NLOp = InsertElementInst::Create(UndefValue::get(ArgTypeH), LOp, CV0,
2685 getReplacementName(IBeforeJ ? I : J,
2686 true, o, 1));
2687 }
2688
2689 NLOp->insertBefore(IBeforeJ ? J : I);
2690 LOp = NLOp;
2691 }
2692
2693 ArgType = ArgTypeH;
2694 } else if (numElemL > numElemH) {
2695 if (numElemH == 1 && expandIEChain(Context, I, J, o, LOp, numElemL,
2696 ArgTypeH, VArgType, IBeforeJ)) {
2697 Instruction *S =
2698 InsertElementInst::Create(LOp, HOp,
2699 ConstantInt::get(Type::getInt32Ty(Context),
2700 numElemL),
2701 getReplacementName(IBeforeJ ? I : J,
2702 true, o));
2703 S->insertBefore(IBeforeJ ? J : I);
2704 return S;
2705 } else if (!expandIEChain(Context, I, J, o, HOp, numElemH, ArgTypeH,
2706 ArgTypeL, IBeforeJ)) {
2707 Instruction *NHOp;
2708 if (numElemH > 1) {
2709 std::vector<Constant *> Mask(numElemL);
2710 unsigned v = 0;
2711 for (; v < numElemH; ++v)
2712 Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
2713 for (; v < numElemL; ++v)
2714 Mask[v] = UndefValue::get(Type::getInt32Ty(Context));
2715
2716 NHOp = new ShuffleVectorInst(HOp, UndefValue::get(ArgTypeH),
2717 ConstantVector::get(Mask),
2718 getReplacementName(IBeforeJ ? I : J,
2719 true, o, 1));
2720 } else {
2721 NHOp = InsertElementInst::Create(UndefValue::get(ArgTypeL), HOp, CV0,
2722 getReplacementName(IBeforeJ ? I : J,
2723 true, o, 1));
2724 }
2725
2726 NHOp->insertBefore(IBeforeJ ? J : I);
2727 HOp = NHOp;
2728 }
2729 }
2730
2731 if (ArgType->isVectorTy()) {
2732 unsigned numElem = VArgType->getVectorNumElements();
2733 std::vector<Constant*> Mask(numElem);
2734 for (unsigned v = 0; v < numElem; ++v) {
2735 unsigned Idx = v;
2736 // If the low vector was expanded, we need to skip the extra
2737 // undefined entries.
2738 if (v >= numElemL && numElemH > numElemL)
2739 Idx += (numElemH - numElemL);
2740 Mask[v] = ConstantInt::get(Type::getInt32Ty(Context), Idx);
2741 }
2742
2743 Instruction *BV = new ShuffleVectorInst(LOp, HOp,
2744 ConstantVector::get(Mask),
2745 getReplacementName(IBeforeJ ? I : J, true, o));
2746 BV->insertBefore(IBeforeJ ? J : I);
2747 return BV;
2748 }
2749
2750 Instruction *BV1 = InsertElementInst::Create(
2751 UndefValue::get(VArgType), LOp, CV0,
2752 getReplacementName(IBeforeJ ? I : J,
2753 true, o, 1));
2754 BV1->insertBefore(IBeforeJ ? J : I);
2755 Instruction *BV2 = InsertElementInst::Create(BV1, HOp, CV1,
2756 getReplacementName(IBeforeJ ? I : J,
2757 true, o, 2));
2758 BV2->insertBefore(IBeforeJ ? J : I);
2759 return BV2;
2760 }
2761
2762 // This function creates an array of values that will be used as the inputs
2763 // to the vector instruction that fuses I with J.
2764 void BBVectorize::getReplacementInputsForPair(LLVMContext& Context,
2765 Instruction *I, Instruction *J,
2766 SmallVectorImpl<Value *> &ReplacedOperands,
2767 bool IBeforeJ) {
2768 unsigned NumOperands = I->getNumOperands();
2769
2770 for (unsigned p = 0, o = NumOperands-1; p < NumOperands; ++p, --o) {
2771 // Iterate backward so that we look at the store pointer
2772 // first and know whether or not we need to flip the inputs.
2773
2774 if (isa<LoadInst>(I) || (o == 1 && isa<StoreInst>(I))) {
2775 // This is the pointer for a load/store instruction.
2776 ReplacedOperands[o] = getReplacementPointerInput(Context, I, J, o);
2777 continue;
2778 } else if (isa<CallInst>(I)) {
2779 Function *F = cast<CallInst>(I)->getCalledFunction();
2780 Intrinsic::ID IID = (Intrinsic::ID) F->getIntrinsicID();
2781 if (o == NumOperands-1) {
2782 BasicBlock &BB = *I->getParent();
2783
2784 Module *M = BB.getParent()->getParent();
2785 Type *ArgTypeI = I->getType();
2786 Type *ArgTypeJ = J->getType();
2787 Type *VArgType = getVecTypeForPair(ArgTypeI, ArgTypeJ);
2788
2789 ReplacedOperands[o] = Intrinsic::getDeclaration(M, IID, VArgType);
2790 continue;
2791 } else if ((IID == Intrinsic::powi || IID == Intrinsic::ctlz ||
2792 IID == Intrinsic::cttz) && o == 1) {
2793 // The second argument of powi/ctlz/cttz is a single integer/constant
2794 // and we've already checked that both arguments are equal.
2795 // As a result, we just keep I's second argument.
2796 ReplacedOperands[o] = I->getOperand(o);
2797 continue;
2798 }
2799 } else if (isa<ShuffleVectorInst>(I) && o == NumOperands-1) {
2800 ReplacedOperands[o] = getReplacementShuffleMask(Context, I, J);
2801 continue;
2802 }
2803
2804 ReplacedOperands[o] = getReplacementInput(Context, I, J, o, IBeforeJ);
2805 }
2806 }
2807
2808 // This function creates two values that represent the outputs of the
2809 // original I and J instructions. These are generally vector shuffles
2810 // or extracts. In many cases, these will end up being unused and, thus,
2811 // eliminated by later passes.
2812 void BBVectorize::replaceOutputsOfPair(LLVMContext& Context, Instruction *I,
2813 Instruction *J, Instruction *K,
2814 Instruction *&InsertionPt,
2815 Instruction *&K1, Instruction *&K2) {
2816 if (isa<StoreInst>(I)) {
2817 AA->replaceWithNewValue(I, K);
2818 AA->replaceWithNewValue(J, K);
2819 } else {
2820 Type *IType = I->getType();
2821 Type *JType = J->getType();
2822
2823 VectorType *VType = getVecTypeForPair(IType, JType);
2824 unsigned numElem = VType->getNumElements();
2825
2826 unsigned numElemI = getNumScalarElements(IType);
2827 unsigned numElemJ = getNumScalarElements(JType);
2828
2829 if (IType->isVectorTy()) {
2830 std::vector<Constant*> Mask1(numElemI), Mask2(numElemI);
2831 for (unsigned v = 0; v < numElemI; ++v) {
2832 Mask1[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
2833 Mask2[v] = ConstantInt::get(Type::getInt32Ty(Context), numElemJ+v);
2834 }
2835
2836 K1 = new ShuffleVectorInst(K, UndefValue::get(VType),
2837 ConstantVector::get( Mask1),
2838 getReplacementName(K, false, 1));
2839 } else {
2840 Value *CV0 = ConstantInt::get(Type::getInt32Ty(Context), 0);
2841 K1 = ExtractElementInst::Create(K, CV0,
2842 getReplacementName(K, false, 1));
2843 }
2844
2845 if (JType->isVectorTy()) {
2846 std::vector<Constant*> Mask1(numElemJ), Mask2(numElemJ);
2847 for (unsigned v = 0; v < numElemJ; ++v) {
2848 Mask1[v] = ConstantInt::get(Type::getInt32Ty(Context), v);
2849 Mask2[v] = ConstantInt::get(Type::getInt32Ty(Context), numElemI+v);
2850 }
2851
2852 K2 = new ShuffleVectorInst(K, UndefValue::get(VType),
2853 ConstantVector::get( Mask2),
2854 getReplacementName(K, false, 2));
2855 } else {
2856 Value *CV1 = ConstantInt::get(Type::getInt32Ty(Context), numElem-1);
2857 K2 = ExtractElementInst::Create(K, CV1,
2858 getReplacementName(K, false, 2));
2859 }
2860
2861 K1->insertAfter(K);
2862 K2->insertAfter(K1);
2863 InsertionPt = K2;
2864 }
2865 }
2866
2867 // Move all uses of the function I (including pairing-induced uses) after J.
2868 bool BBVectorize::canMoveUsesOfIAfterJ(BasicBlock &BB,
2869 DenseSet<ValuePair> &LoadMoveSetPairs,
2870 Instruction *I, Instruction *J) {
2871 // Skip to the first instruction past I.
2872 BasicBlock::iterator L = std::next(BasicBlock::iterator(I));
2873
2874 DenseSet<Value *> Users;
2875 AliasSetTracker WriteSet(*AA);
2876 if (I->mayWriteToMemory()) WriteSet.add(I);
2877
2878 for (; cast<Instruction>(L) != J; ++L)
2879 (void) trackUsesOfI(Users, WriteSet, I, L, true, &LoadMoveSetPairs);
2880
2881 assert(cast<Instruction>(L) == J &&((cast<Instruction>(L) == J && "Tracking has not proceeded far enough to check for dependencies"
) ? static_cast<void> (0) : __assert_fail ("cast<Instruction>(L) == J && \"Tracking has not proceeded far enough to check for dependencies\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 2882, __PRETTY_FUNCTION__))
2882 "Tracking has not proceeded far enough to check for dependencies")((cast<Instruction>(L) == J && "Tracking has not proceeded far enough to check for dependencies"
) ? static_cast<void> (0) : __assert_fail ("cast<Instruction>(L) == J && \"Tracking has not proceeded far enough to check for dependencies\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 2882, __PRETTY_FUNCTION__))
;
2883 // If J is now in the use set of I, then trackUsesOfI will return true
2884 // and we have a dependency cycle (and the fusing operation must abort).
2885 return !trackUsesOfI(Users, WriteSet, I, J, true, &LoadMoveSetPairs);
2886 }
2887
2888 // Move all uses of the function I (including pairing-induced uses) after J.
2889 void BBVectorize::moveUsesOfIAfterJ(BasicBlock &BB,
2890 DenseSet<ValuePair> &LoadMoveSetPairs,
2891 Instruction *&InsertionPt,
2892 Instruction *I, Instruction *J) {
2893 // Skip to the first instruction past I.
2894 BasicBlock::iterator L = std::next(BasicBlock::iterator(I));
2895
2896 DenseSet<Value *> Users;
2897 AliasSetTracker WriteSet(*AA);
2898 if (I->mayWriteToMemory()) WriteSet.add(I);
2899
2900 for (; cast<Instruction>(L) != J;) {
2901 if (trackUsesOfI(Users, WriteSet, I, L, true, &LoadMoveSetPairs)) {
2902 // Move this instruction
2903 Instruction *InstToMove = L; ++L;
2904
2905 DEBUG(dbgs() << "BBV: moving: " << *InstToMove <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: moving: " << *
InstToMove << " to after " << *InsertionPt <<
"\n"; } } while (0)
2906 " to after " << *InsertionPt << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: moving: " << *
InstToMove << " to after " << *InsertionPt <<
"\n"; } } while (0)
;
2907 InstToMove->removeFromParent();
2908 InstToMove->insertAfter(InsertionPt);
2909 InsertionPt = InstToMove;
2910 } else {
2911 ++L;
2912 }
2913 }
2914 }
2915
2916 // Collect all load instruction that are in the move set of a given first
2917 // pair member. These loads depend on the first instruction, I, and so need
2918 // to be moved after J (the second instruction) when the pair is fused.
2919 void BBVectorize::collectPairLoadMoveSet(BasicBlock &BB,
2920 DenseMap<Value *, Value *> &ChosenPairs,
2921 DenseMap<Value *, std::vector<Value *> > &LoadMoveSet,
2922 DenseSet<ValuePair> &LoadMoveSetPairs,
2923 Instruction *I) {
2924 // Skip to the first instruction past I.
2925 BasicBlock::iterator L = std::next(BasicBlock::iterator(I));
2926
2927 DenseSet<Value *> Users;
2928 AliasSetTracker WriteSet(*AA);
2929 if (I->mayWriteToMemory()) WriteSet.add(I);
2930
2931 // Note: We cannot end the loop when we reach J because J could be moved
2932 // farther down the use chain by another instruction pairing. Also, J
2933 // could be before I if this is an inverted input.
2934 for (BasicBlock::iterator E = BB.end(); cast<Instruction>(L) != E; ++L) {
2935 if (trackUsesOfI(Users, WriteSet, I, L)) {
2936 if (L->mayReadFromMemory()) {
2937 LoadMoveSet[L].push_back(I);
2938 LoadMoveSetPairs.insert(ValuePair(L, I));
2939 }
2940 }
2941 }
2942 }
2943
2944 // In cases where both load/stores and the computation of their pointers
2945 // are chosen for vectorization, we can end up in a situation where the
2946 // aliasing analysis starts returning different query results as the
2947 // process of fusing instruction pairs continues. Because the algorithm
2948 // relies on finding the same use dags here as were found earlier, we'll
2949 // need to precompute the necessary aliasing information here and then
2950 // manually update it during the fusion process.
2951 void BBVectorize::collectLoadMoveSet(BasicBlock &BB,
2952 std::vector<Value *> &PairableInsts,
2953 DenseMap<Value *, Value *> &ChosenPairs,
2954 DenseMap<Value *, std::vector<Value *> > &LoadMoveSet,
2955 DenseSet<ValuePair> &LoadMoveSetPairs) {
2956 for (std::vector<Value *>::iterator PI = PairableInsts.begin(),
2957 PIE = PairableInsts.end(); PI != PIE; ++PI) {
2958 DenseMap<Value *, Value *>::iterator P = ChosenPairs.find(*PI);
2959 if (P == ChosenPairs.end()) continue;
2960
2961 Instruction *I = cast<Instruction>(P->first);
2962 collectPairLoadMoveSet(BB, ChosenPairs, LoadMoveSet,
2963 LoadMoveSetPairs, I);
2964 }
2965 }
2966
2967 // This function fuses the chosen instruction pairs into vector instructions,
2968 // taking care preserve any needed scalar outputs and, then, it reorders the
2969 // remaining instructions as needed (users of the first member of the pair
2970 // need to be moved to after the location of the second member of the pair
2971 // because the vector instruction is inserted in the location of the pair's
2972 // second member).
2973 void BBVectorize::fuseChosenPairs(BasicBlock &BB,
2974 std::vector<Value *> &PairableInsts,
2975 DenseMap<Value *, Value *> &ChosenPairs,
2976 DenseSet<ValuePair> &FixedOrderPairs,
2977 DenseMap<VPPair, unsigned> &PairConnectionTypes,
2978 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairs,
2979 DenseMap<ValuePair, std::vector<ValuePair> > &ConnectedPairDeps) {
2980 LLVMContext& Context = BB.getContext();
2981
2982 // During the vectorization process, the order of the pairs to be fused
2983 // could be flipped. So we'll add each pair, flipped, into the ChosenPairs
2984 // list. After a pair is fused, the flipped pair is removed from the list.
2985 DenseSet<ValuePair> FlippedPairs;
2986 for (DenseMap<Value *, Value *>::iterator P = ChosenPairs.begin(),
2987 E = ChosenPairs.end(); P != E; ++P)
2988 FlippedPairs.insert(ValuePair(P->second, P->first));
2989 for (DenseSet<ValuePair>::iterator P = FlippedPairs.begin(),
2990 E = FlippedPairs.end(); P != E; ++P)
2991 ChosenPairs.insert(*P);
2992
2993 DenseMap<Value *, std::vector<Value *> > LoadMoveSet;
2994 DenseSet<ValuePair> LoadMoveSetPairs;
2995 collectLoadMoveSet(BB, PairableInsts, ChosenPairs,
2996 LoadMoveSet, LoadMoveSetPairs);
2997
2998 DEBUG(dbgs() << "BBV: initial: \n" << BB << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: initial: \n" <<
BB << "\n"; } } while (0)
;
2999
3000 for (BasicBlock::iterator PI = BB.getFirstInsertionPt(); PI != BB.end();) {
3001 DenseMap<Value *, Value *>::iterator P = ChosenPairs.find(PI);
3002 if (P == ChosenPairs.end()) {
3003 ++PI;
3004 continue;
3005 }
3006
3007 if (getDepthFactor(P->first) == 0) {
3008 // These instructions are not really fused, but are tracked as though
3009 // they are. Any case in which it would be interesting to fuse them
3010 // will be taken care of by InstCombine.
3011 --NumFusedOps;
3012 ++PI;
3013 continue;
3014 }
3015
3016 Instruction *I = cast<Instruction>(P->first),
3017 *J = cast<Instruction>(P->second);
3018
3019 DEBUG(dbgs() << "BBV: fusing: " << *I <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusing: " << *
I << " <-> " << *J << "\n"; } } while
(0)
3020 " <-> " << *J << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusing: " << *
I << " <-> " << *J << "\n"; } } while
(0)
;
3021
3022 // Remove the pair and flipped pair from the list.
3023 DenseMap<Value *, Value *>::iterator FP = ChosenPairs.find(P->second);
3024 assert(FP != ChosenPairs.end() && "Flipped pair not found in list")((FP != ChosenPairs.end() && "Flipped pair not found in list"
) ? static_cast<void> (0) : __assert_fail ("FP != ChosenPairs.end() && \"Flipped pair not found in list\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3024, __PRETTY_FUNCTION__))
;
3025 ChosenPairs.erase(FP);
3026 ChosenPairs.erase(P);
3027
3028 if (!canMoveUsesOfIAfterJ(BB, LoadMoveSetPairs, I, J)) {
3029 DEBUG(dbgs() << "BBV: fusion of: " << *I <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusion of: " <<
*I << " <-> " << *J << " aborted because of non-trivial dependency cycle\n"
; } } while (0)
3030 " <-> " << *J <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusion of: " <<
*I << " <-> " << *J << " aborted because of non-trivial dependency cycle\n"
; } } while (0)
3031 " aborted because of non-trivial dependency cycle\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: fusion of: " <<
*I << " <-> " << *J << " aborted because of non-trivial dependency cycle\n"
; } } while (0)
;
3032 --NumFusedOps;
3033 ++PI;
3034 continue;
3035 }
3036
3037 // If the pair must have the other order, then flip it.
3038 bool FlipPairOrder = FixedOrderPairs.count(ValuePair(J, I));
3039 if (!FlipPairOrder && !FixedOrderPairs.count(ValuePair(I, J))) {
3040 // This pair does not have a fixed order, and so we might want to
3041 // flip it if that will yield fewer shuffles. We count the number
3042 // of dependencies connected via swaps, and those directly connected,
3043 // and flip the order if the number of swaps is greater.
3044 bool OrigOrder = true;
3045 DenseMap<ValuePair, std::vector<ValuePair> >::iterator IJ =
3046 ConnectedPairDeps.find(ValuePair(I, J));
3047 if (IJ == ConnectedPairDeps.end()) {
3048 IJ = ConnectedPairDeps.find(ValuePair(J, I));
3049 OrigOrder = false;
3050 }
3051
3052 if (IJ != ConnectedPairDeps.end()) {
3053 unsigned NumDepsDirect = 0, NumDepsSwap = 0;
3054 for (std::vector<ValuePair>::iterator T = IJ->second.begin(),
3055 TE = IJ->second.end(); T != TE; ++T) {
3056 VPPair Q(IJ->first, *T);
3057 DenseMap<VPPair, unsigned>::iterator R =
3058 PairConnectionTypes.find(VPPair(Q.second, Q.first));
3059 assert(R != PairConnectionTypes.end() &&((R != PairConnectionTypes.end() && "Cannot find pair connection type"
) ? static_cast<void> (0) : __assert_fail ("R != PairConnectionTypes.end() && \"Cannot find pair connection type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3060, __PRETTY_FUNCTION__))
3060 "Cannot find pair connection type")((R != PairConnectionTypes.end() && "Cannot find pair connection type"
) ? static_cast<void> (0) : __assert_fail ("R != PairConnectionTypes.end() && \"Cannot find pair connection type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3060, __PRETTY_FUNCTION__))
;
3061 if (R->second == PairConnectionDirect)
3062 ++NumDepsDirect;
3063 else if (R->second == PairConnectionSwap)
3064 ++NumDepsSwap;
3065 }
3066
3067 if (!OrigOrder)
3068 std::swap(NumDepsDirect, NumDepsSwap);
3069
3070 if (NumDepsSwap > NumDepsDirect) {
3071 FlipPairOrder = true;
3072 DEBUG(dbgs() << "BBV: reordering pair: " << *I <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: reordering pair: " <<
*I << " <-> " << *J << "\n"; } } while
(0)
3073 " <-> " << *J << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: reordering pair: " <<
*I << " <-> " << *J << "\n"; } } while
(0)
;
3074 }
3075 }
3076 }
3077
3078 Instruction *L = I, *H = J;
3079 if (FlipPairOrder)
3080 std::swap(H, L);
3081
3082 // If the pair being fused uses the opposite order from that in the pair
3083 // connection map, then we need to flip the types.
3084 DenseMap<ValuePair, std::vector<ValuePair> >::iterator HL =
3085 ConnectedPairs.find(ValuePair(H, L));
3086 if (HL != ConnectedPairs.end())
3087 for (std::vector<ValuePair>::iterator T = HL->second.begin(),
3088 TE = HL->second.end(); T != TE; ++T) {
3089 VPPair Q(HL->first, *T);
3090 DenseMap<VPPair, unsigned>::iterator R = PairConnectionTypes.find(Q);
3091 assert(R != PairConnectionTypes.end() &&((R != PairConnectionTypes.end() && "Cannot find pair connection type"
) ? static_cast<void> (0) : __assert_fail ("R != PairConnectionTypes.end() && \"Cannot find pair connection type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3092, __PRETTY_FUNCTION__))
3092 "Cannot find pair connection type")((R != PairConnectionTypes.end() && "Cannot find pair connection type"
) ? static_cast<void> (0) : __assert_fail ("R != PairConnectionTypes.end() && \"Cannot find pair connection type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3092, __PRETTY_FUNCTION__))
;
3093 if (R->second == PairConnectionDirect)
3094 R->second = PairConnectionSwap;
3095 else if (R->second == PairConnectionSwap)
3096 R->second = PairConnectionDirect;
3097 }
3098
3099 bool LBeforeH = !FlipPairOrder;
3100 unsigned NumOperands = I->getNumOperands();
3101 SmallVector<Value *, 3> ReplacedOperands(NumOperands);
3102 getReplacementInputsForPair(Context, L, H, ReplacedOperands,
3103 LBeforeH);
3104
3105 // Make a copy of the original operation, change its type to the vector
3106 // type and replace its operands with the vector operands.
3107 Instruction *K = L->clone();
3108 if (L->hasName())
3109 K->takeName(L);
3110 else if (H->hasName())
3111 K->takeName(H);
3112
3113 if (!isa<StoreInst>(K))
3114 K->mutateType(getVecTypeForPair(L->getType(), H->getType()));
3115
3116 unsigned KnownIDs[] = {
3117 LLVMContext::MD_tbaa,
3118 LLVMContext::MD_alias_scope,
3119 LLVMContext::MD_noalias,
3120 LLVMContext::MD_fpmath
3121 };
3122 combineMetadata(K, H, KnownIDs);
3123 K->intersectOptionalDataWith(H);
3124
3125 for (unsigned o = 0; o < NumOperands; ++o)
3126 K->setOperand(o, ReplacedOperands[o]);
3127
3128 K->insertAfter(J);
3129
3130 // Instruction insertion point:
3131 Instruction *InsertionPt = K;
3132 Instruction *K1 = nullptr, *K2 = nullptr;
3133 replaceOutputsOfPair(Context, L, H, K, InsertionPt, K1, K2);
3134
3135 // The use dag of the first original instruction must be moved to after
3136 // the location of the second instruction. The entire use dag of the
3137 // first instruction is disjoint from the input dag of the second
3138 // (by definition), and so commutes with it.
3139
3140 moveUsesOfIAfterJ(BB, LoadMoveSetPairs, InsertionPt, I, J);
3141
3142 if (!isa<StoreInst>(I)) {
3143 L->replaceAllUsesWith(K1);
3144 H->replaceAllUsesWith(K2);
3145 AA->replaceWithNewValue(L, K1);
3146 AA->replaceWithNewValue(H, K2);
3147 }
3148
3149 // Instructions that may read from memory may be in the load move set.
3150 // Once an instruction is fused, we no longer need its move set, and so
3151 // the values of the map never need to be updated. However, when a load
3152 // is fused, we need to merge the entries from both instructions in the
3153 // pair in case those instructions were in the move set of some other
3154 // yet-to-be-fused pair. The loads in question are the keys of the map.
3155 if (I->mayReadFromMemory()) {
3156 std::vector<ValuePair> NewSetMembers;
3157 DenseMap<Value *, std::vector<Value *> >::iterator II =
3158 LoadMoveSet.find(I);
3159 if (II != LoadMoveSet.end())
3160 for (std::vector<Value *>::iterator N = II->second.begin(),
3161 NE = II->second.end(); N != NE; ++N)
3162 NewSetMembers.push_back(ValuePair(K, *N));
3163 DenseMap<Value *, std::vector<Value *> >::iterator JJ =
3164 LoadMoveSet.find(J);
3165 if (JJ != LoadMoveSet.end())
3166 for (std::vector<Value *>::iterator N = JJ->second.begin(),
3167 NE = JJ->second.end(); N != NE; ++N)
3168 NewSetMembers.push_back(ValuePair(K, *N));
3169 for (std::vector<ValuePair>::iterator A = NewSetMembers.begin(),
3170 AE = NewSetMembers.end(); A != AE; ++A) {
3171 LoadMoveSet[A->first].push_back(A->second);
3172 LoadMoveSetPairs.insert(*A);
3173 }
3174 }
3175
3176 // Before removing I, set the iterator to the next instruction.
3177 PI = std::next(BasicBlock::iterator(I));
3178 if (cast<Instruction>(PI) == J)
3179 ++PI;
3180
3181 SE->forgetValue(I);
3182 SE->forgetValue(J);
3183 I->eraseFromParent();
3184 J->eraseFromParent();
3185
3186 DEBUG(if (PrintAfterEveryPair) dbgs() << "BBV: block is now: \n" <<do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (PrintAfterEveryPair) dbgs() << "BBV: block is now: \n"
<< BB << "\n"; } } while (0)
3187 BB << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { if (PrintAfterEveryPair) dbgs() << "BBV: block is now: \n"
<< BB << "\n"; } } while (0)
;
3188 }
3189
3190 DEBUG(dbgs() << "BBV: final: \n" << BB << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("bb-vectorize")) { dbgs() << "BBV: final: \n" <<
BB << "\n"; } } while (0)
;
3191 }
3192}
3193
3194char BBVectorize::ID = 0;
3195static const char bb_vectorize_name[] = "Basic-Block Vectorization";
3196INITIALIZE_PASS_BEGIN(BBVectorize, BBV_NAME, bb_vectorize_name, false, false)static void* initializeBBVectorizePassOnce(PassRegistry &
Registry) {
3197INITIALIZE_AG_DEPENDENCY(AliasAnalysis)initializeAliasAnalysisAnalysisGroup(Registry);
3198INITIALIZE_AG_DEPENDENCY(TargetTransformInfo)initializeTargetTransformInfoAnalysisGroup(Registry);
3199INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)initializeDominatorTreeWrapperPassPass(Registry);
3200INITIALIZE_PASS_DEPENDENCY(ScalarEvolution)initializeScalarEvolutionPass(Registry);
3201INITIALIZE_PASS_END(BBVectorize, BBV_NAME, bb_vectorize_name, false, false)PassInfo *PI = new PassInfo(bb_vectorize_name, "bb-vectorize"
, & BBVectorize ::ID, PassInfo::NormalCtor_t(callDefaultCtor
< BBVectorize >), false, false); Registry.registerPass(
*PI, true); return PI; } void llvm::initializeBBVectorizePass
(PassRegistry &Registry) { static volatile sys::cas_flag initialized
= 0; sys::cas_flag old_val = sys::CompareAndSwap(&initialized
, 1, 0); if (old_val == 0) { initializeBBVectorizePassOnce(Registry
); sys::MemoryFence(); AnnotateIgnoreWritesBegin("/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3201); AnnotateHappensBefore("/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3201, &initialized); initialized = 2; AnnotateIgnoreWritesEnd
("/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3201); } else { sys::cas_flag tmp = initialized; sys::MemoryFence
(); while (tmp != 2) { tmp = initialized; sys::MemoryFence();
} } AnnotateHappensAfter("/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224456/lib/Transforms/Vectorize/BBVectorize.cpp"
, 3201, &initialized); }
3202
3203BasicBlockPass *llvm::createBBVectorizePass(const VectorizeConfig &C) {
3204 return new BBVectorize(C);
3205}
3206
3207bool
3208llvm::vectorizeBasicBlock(Pass *P, BasicBlock &BB, const VectorizeConfig &C) {
3209 BBVectorize BBVectorizer(P, C);
3210 return BBVectorizer.vectorizeBB(BB);
3211}
3212
3213//===----------------------------------------------------------------------===//
3214VectorizeConfig::VectorizeConfig() {
3215 VectorBits = ::VectorBits;
3216 VectorizeBools = !::NoBools;
3217 VectorizeInts = !::NoInts;
3218 VectorizeFloats = !::NoFloats;
3219 VectorizePointers = !::NoPointers;
3220 VectorizeCasts = !::NoCasts;
3221 VectorizeMath = !::NoMath;
3222 VectorizeBitManipulations = !::NoBitManipulation;
3223 VectorizeFMA = !::NoFMA;
3224 VectorizeSelect = !::NoSelect;
3225 VectorizeCmp = !::NoCmp;
3226 VectorizeGEP = !::NoGEP;
3227 VectorizeMemOps = !::NoMemOps;
3228 AlignedOnly = ::AlignedOnly;
3229 ReqChainDepth= ::ReqChainDepth;
3230 SearchLimit = ::SearchLimit;
3231 MaxCandPairsForCycleCheck = ::MaxCandPairsForCycleCheck;
3232 SplatBreaksChain = ::SplatBreaksChain;
3233 MaxInsts = ::MaxInsts;
3234 MaxPairs = ::MaxPairs;
3235 MaxIter = ::MaxIter;
3236 Pow2LenOnly = ::Pow2LenOnly;
3237 NoMemOpBoost = ::NoMemOpBoost;
3238 FastDep = ::FastDep;
3239}