File: | llvm/lib/Transforms/IPO/AttributorAttributes.cpp |
Warning: | line 387, column 5 Forming reference to null pointer |
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1 | //===- AttributorAttributes.cpp - Attributes for Attributor deduction -----===// | ||||
2 | // | ||||
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | ||||
4 | // See https://llvm.org/LICENSE.txt for license information. | ||||
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | ||||
6 | // | ||||
7 | //===----------------------------------------------------------------------===// | ||||
8 | // | ||||
9 | // See the Attributor.h file comment and the class descriptions in that file for | ||||
10 | // more information. | ||||
11 | // | ||||
12 | //===----------------------------------------------------------------------===// | ||||
13 | |||||
14 | #include "llvm/Transforms/IPO/Attributor.h" | ||||
15 | |||||
16 | #include "llvm/ADT/APInt.h" | ||||
17 | #include "llvm/ADT/SCCIterator.h" | ||||
18 | #include "llvm/ADT/SmallPtrSet.h" | ||||
19 | #include "llvm/ADT/Statistic.h" | ||||
20 | #include "llvm/Analysis/AliasAnalysis.h" | ||||
21 | #include "llvm/Analysis/AssumeBundleQueries.h" | ||||
22 | #include "llvm/Analysis/AssumptionCache.h" | ||||
23 | #include "llvm/Analysis/CaptureTracking.h" | ||||
24 | #include "llvm/Analysis/InstructionSimplify.h" | ||||
25 | #include "llvm/Analysis/LazyValueInfo.h" | ||||
26 | #include "llvm/Analysis/MemoryBuiltins.h" | ||||
27 | #include "llvm/Analysis/OptimizationRemarkEmitter.h" | ||||
28 | #include "llvm/Analysis/ScalarEvolution.h" | ||||
29 | #include "llvm/Analysis/TargetTransformInfo.h" | ||||
30 | #include "llvm/Analysis/ValueTracking.h" | ||||
31 | #include "llvm/IR/Constants.h" | ||||
32 | #include "llvm/IR/IRBuilder.h" | ||||
33 | #include "llvm/IR/Instruction.h" | ||||
34 | #include "llvm/IR/Instructions.h" | ||||
35 | #include "llvm/IR/IntrinsicInst.h" | ||||
36 | #include "llvm/IR/NoFolder.h" | ||||
37 | #include "llvm/Support/Alignment.h" | ||||
38 | #include "llvm/Support/Casting.h" | ||||
39 | #include "llvm/Support/CommandLine.h" | ||||
40 | #include "llvm/Support/ErrorHandling.h" | ||||
41 | #include "llvm/Support/FileSystem.h" | ||||
42 | #include "llvm/Support/raw_ostream.h" | ||||
43 | #include "llvm/Transforms/IPO/ArgumentPromotion.h" | ||||
44 | #include "llvm/Transforms/Utils/Local.h" | ||||
45 | #include <cassert> | ||||
46 | |||||
47 | using namespace llvm; | ||||
48 | |||||
49 | #define DEBUG_TYPE"attributor" "attributor" | ||||
50 | |||||
51 | static cl::opt<bool> ManifestInternal( | ||||
52 | "attributor-manifest-internal", cl::Hidden, | ||||
53 | cl::desc("Manifest Attributor internal string attributes."), | ||||
54 | cl::init(false)); | ||||
55 | |||||
56 | static cl::opt<int> MaxHeapToStackSize("max-heap-to-stack-size", cl::init(128), | ||||
57 | cl::Hidden); | ||||
58 | |||||
59 | template <> | ||||
60 | unsigned llvm::PotentialConstantIntValuesState::MaxPotentialValues = 0; | ||||
61 | |||||
62 | static cl::opt<unsigned, true> MaxPotentialValues( | ||||
63 | "attributor-max-potential-values", cl::Hidden, | ||||
64 | cl::desc("Maximum number of potential values to be " | ||||
65 | "tracked for each position."), | ||||
66 | cl::location(llvm::PotentialConstantIntValuesState::MaxPotentialValues), | ||||
67 | cl::init(7)); | ||||
68 | |||||
69 | STATISTIC(NumAAs, "Number of abstract attributes created")static llvm::Statistic NumAAs = {"attributor", "NumAAs", "Number of abstract attributes created" }; | ||||
70 | |||||
71 | // Some helper macros to deal with statistics tracking. | ||||
72 | // | ||||
73 | // Usage: | ||||
74 | // For simple IR attribute tracking overload trackStatistics in the abstract | ||||
75 | // attribute and choose the right STATS_DECLTRACK_********* macro, | ||||
76 | // e.g.,: | ||||
77 | // void trackStatistics() const override { | ||||
78 | // STATS_DECLTRACK_ARG_ATTR(returned) | ||||
79 | // } | ||||
80 | // If there is a single "increment" side one can use the macro | ||||
81 | // STATS_DECLTRACK with a custom message. If there are multiple increment | ||||
82 | // sides, STATS_DECL and STATS_TRACK can also be used separately. | ||||
83 | // | ||||
84 | #define BUILD_STAT_MSG_IR_ATTR(TYPE, NAME)("Number of " "TYPE" " marked '" "NAME" "'") \ | ||||
85 | ("Number of " #TYPE " marked '" #NAME "'") | ||||
86 | #define BUILD_STAT_NAME(NAME, TYPE)NumIRTYPE_NAME NumIR##TYPE##_##NAME | ||||
87 | #define STATS_DECL_(NAME, MSG)static llvm::Statistic NAME = {"attributor", "NAME", MSG}; STATISTIC(NAME, MSG)static llvm::Statistic NAME = {"attributor", "NAME", MSG}; | ||||
88 | #define STATS_DECL(NAME, TYPE, MSG)static llvm::Statistic NumIRTYPE_NAME = {"attributor", "NumIRTYPE_NAME" , MSG};; \ | ||||
89 | STATS_DECL_(BUILD_STAT_NAME(NAME, TYPE), MSG)static llvm::Statistic NumIRTYPE_NAME = {"attributor", "NumIRTYPE_NAME" , MSG};; | ||||
90 | #define STATS_TRACK(NAME, TYPE)++(NumIRTYPE_NAME); ++(BUILD_STAT_NAME(NAME, TYPE)NumIRTYPE_NAME); | ||||
91 | #define STATS_DECLTRACK(NAME, TYPE, MSG){ static llvm::Statistic NumIRTYPE_NAME = {"attributor", "NumIRTYPE_NAME" , MSG};; ++(NumIRTYPE_NAME); } \ | ||||
92 | { \ | ||||
93 | STATS_DECL(NAME, TYPE, MSG)static llvm::Statistic NumIRTYPE_NAME = {"attributor", "NumIRTYPE_NAME" , MSG};; \ | ||||
94 | STATS_TRACK(NAME, TYPE)++(NumIRTYPE_NAME); \ | ||||
95 | } | ||||
96 | #define STATS_DECLTRACK_ARG_ATTR(NAME){ static llvm::Statistic NumIRArguments_NAME = {"attributor", "NumIRArguments_NAME", ("Number of " "arguments" " marked '" "NAME" "'")};; ++(NumIRArguments_NAME); } \ | ||||
97 | STATS_DECLTRACK(NAME, Arguments, BUILD_STAT_MSG_IR_ATTR(arguments, NAME)){ static llvm::Statistic NumIRArguments_NAME = {"attributor", "NumIRArguments_NAME", ("Number of " "arguments" " marked '" "NAME" "'")};; ++(NumIRArguments_NAME); } | ||||
98 | #define STATS_DECLTRACK_CSARG_ATTR(NAME){ static llvm::Statistic NumIRCSArguments_NAME = {"attributor" , "NumIRCSArguments_NAME", ("Number of " "call site arguments" " marked '" "NAME" "'")};; ++(NumIRCSArguments_NAME); } \ | ||||
99 | STATS_DECLTRACK(NAME, CSArguments, \{ static llvm::Statistic NumIRCSArguments_NAME = {"attributor" , "NumIRCSArguments_NAME", ("Number of " "call site arguments" " marked '" "NAME" "'")};; ++(NumIRCSArguments_NAME); } | ||||
100 | BUILD_STAT_MSG_IR_ATTR(call site arguments, NAME)){ static llvm::Statistic NumIRCSArguments_NAME = {"attributor" , "NumIRCSArguments_NAME", ("Number of " "call site arguments" " marked '" "NAME" "'")};; ++(NumIRCSArguments_NAME); } | ||||
101 | #define STATS_DECLTRACK_FN_ATTR(NAME){ static llvm::Statistic NumIRFunction_NAME = {"attributor", "NumIRFunction_NAME" , ("Number of " "functions" " marked '" "NAME" "'")};; ++(NumIRFunction_NAME ); } \ | ||||
102 | STATS_DECLTRACK(NAME, Function, BUILD_STAT_MSG_IR_ATTR(functions, NAME)){ static llvm::Statistic NumIRFunction_NAME = {"attributor", "NumIRFunction_NAME" , ("Number of " "functions" " marked '" "NAME" "'")};; ++(NumIRFunction_NAME ); } | ||||
103 | #define STATS_DECLTRACK_CS_ATTR(NAME){ static llvm::Statistic NumIRCS_NAME = {"attributor", "NumIRCS_NAME" , ("Number of " "call site" " marked '" "NAME" "'")};; ++(NumIRCS_NAME ); } \ | ||||
104 | STATS_DECLTRACK(NAME, CS, BUILD_STAT_MSG_IR_ATTR(call site, NAME)){ static llvm::Statistic NumIRCS_NAME = {"attributor", "NumIRCS_NAME" , ("Number of " "call site" " marked '" "NAME" "'")};; ++(NumIRCS_NAME ); } | ||||
105 | #define STATS_DECLTRACK_FNRET_ATTR(NAME){ static llvm::Statistic NumIRFunctionReturn_NAME = {"attributor" , "NumIRFunctionReturn_NAME", ("Number of " "function returns" " marked '" "NAME" "'")};; ++(NumIRFunctionReturn_NAME); } \ | ||||
106 | STATS_DECLTRACK(NAME, FunctionReturn, \{ static llvm::Statistic NumIRFunctionReturn_NAME = {"attributor" , "NumIRFunctionReturn_NAME", ("Number of " "function returns" " marked '" "NAME" "'")};; ++(NumIRFunctionReturn_NAME); } | ||||
107 | BUILD_STAT_MSG_IR_ATTR(function returns, NAME)){ static llvm::Statistic NumIRFunctionReturn_NAME = {"attributor" , "NumIRFunctionReturn_NAME", ("Number of " "function returns" " marked '" "NAME" "'")};; ++(NumIRFunctionReturn_NAME); } | ||||
108 | #define STATS_DECLTRACK_CSRET_ATTR(NAME){ static llvm::Statistic NumIRCSReturn_NAME = {"attributor", "NumIRCSReturn_NAME" , ("Number of " "call site returns" " marked '" "NAME" "'")}; ; ++(NumIRCSReturn_NAME); } \ | ||||
109 | STATS_DECLTRACK(NAME, CSReturn, \{ static llvm::Statistic NumIRCSReturn_NAME = {"attributor", "NumIRCSReturn_NAME" , ("Number of " "call site returns" " marked '" "NAME" "'")}; ; ++(NumIRCSReturn_NAME); } | ||||
110 | BUILD_STAT_MSG_IR_ATTR(call site returns, NAME)){ static llvm::Statistic NumIRCSReturn_NAME = {"attributor", "NumIRCSReturn_NAME" , ("Number of " "call site returns" " marked '" "NAME" "'")}; ; ++(NumIRCSReturn_NAME); } | ||||
111 | #define STATS_DECLTRACK_FLOATING_ATTR(NAME){ static llvm::Statistic NumIRFloating_NAME = {"attributor", "NumIRFloating_NAME" , ("Number of floating values known to be '" "NAME" "'")};; ++ (NumIRFloating_NAME); } \ | ||||
112 | STATS_DECLTRACK(NAME, Floating, \{ static llvm::Statistic NumIRFloating_NAME = {"attributor", "NumIRFloating_NAME" , ("Number of floating values known to be '" #NAME "'")};; ++ (NumIRFloating_NAME); } | ||||
113 | ("Number of floating values known to be '" #NAME "'")){ static llvm::Statistic NumIRFloating_NAME = {"attributor", "NumIRFloating_NAME" , ("Number of floating values known to be '" #NAME "'")};; ++ (NumIRFloating_NAME); } | ||||
114 | |||||
115 | // Specialization of the operator<< for abstract attributes subclasses. This | ||||
116 | // disambiguates situations where multiple operators are applicable. | ||||
117 | namespace llvm { | ||||
118 | #define PIPE_OPERATOR(CLASS) \ | ||||
119 | raw_ostream &operator<<(raw_ostream &OS, const CLASS &AA) { \ | ||||
120 | return OS << static_cast<const AbstractAttribute &>(AA); \ | ||||
121 | } | ||||
122 | |||||
123 | PIPE_OPERATOR(AAIsDead) | ||||
124 | PIPE_OPERATOR(AANoUnwind) | ||||
125 | PIPE_OPERATOR(AANoSync) | ||||
126 | PIPE_OPERATOR(AANoRecurse) | ||||
127 | PIPE_OPERATOR(AAWillReturn) | ||||
128 | PIPE_OPERATOR(AANoReturn) | ||||
129 | PIPE_OPERATOR(AAReturnedValues) | ||||
130 | PIPE_OPERATOR(AANonNull) | ||||
131 | PIPE_OPERATOR(AANoAlias) | ||||
132 | PIPE_OPERATOR(AADereferenceable) | ||||
133 | PIPE_OPERATOR(AAAlign) | ||||
134 | PIPE_OPERATOR(AANoCapture) | ||||
135 | PIPE_OPERATOR(AAValueSimplify) | ||||
136 | PIPE_OPERATOR(AANoFree) | ||||
137 | PIPE_OPERATOR(AAHeapToStack) | ||||
138 | PIPE_OPERATOR(AAReachability) | ||||
139 | PIPE_OPERATOR(AAMemoryBehavior) | ||||
140 | PIPE_OPERATOR(AAMemoryLocation) | ||||
141 | PIPE_OPERATOR(AAValueConstantRange) | ||||
142 | PIPE_OPERATOR(AAPrivatizablePtr) | ||||
143 | PIPE_OPERATOR(AAUndefinedBehavior) | ||||
144 | PIPE_OPERATOR(AAPotentialValues) | ||||
145 | PIPE_OPERATOR(AANoUndef) | ||||
146 | PIPE_OPERATOR(AACallEdges) | ||||
147 | PIPE_OPERATOR(AAFunctionReachability) | ||||
148 | PIPE_OPERATOR(AAPointerInfo) | ||||
149 | |||||
150 | #undef PIPE_OPERATOR | ||||
151 | |||||
152 | template <> | ||||
153 | ChangeStatus clampStateAndIndicateChange<DerefState>(DerefState &S, | ||||
154 | const DerefState &R) { | ||||
155 | ChangeStatus CS0 = | ||||
156 | clampStateAndIndicateChange(S.DerefBytesState, R.DerefBytesState); | ||||
157 | ChangeStatus CS1 = clampStateAndIndicateChange(S.GlobalState, R.GlobalState); | ||||
158 | return CS0 | CS1; | ||||
159 | } | ||||
160 | |||||
161 | } // namespace llvm | ||||
162 | |||||
163 | /// Get pointer operand of memory accessing instruction. If \p I is | ||||
164 | /// not a memory accessing instruction, return nullptr. If \p AllowVolatile, | ||||
165 | /// is set to false and the instruction is volatile, return nullptr. | ||||
166 | static const Value *getPointerOperand(const Instruction *I, | ||||
167 | bool AllowVolatile) { | ||||
168 | if (!AllowVolatile && I->isVolatile()) | ||||
169 | return nullptr; | ||||
170 | |||||
171 | if (auto *LI = dyn_cast<LoadInst>(I)) { | ||||
172 | return LI->getPointerOperand(); | ||||
173 | } | ||||
174 | |||||
175 | if (auto *SI = dyn_cast<StoreInst>(I)) { | ||||
176 | return SI->getPointerOperand(); | ||||
177 | } | ||||
178 | |||||
179 | if (auto *CXI = dyn_cast<AtomicCmpXchgInst>(I)) { | ||||
180 | return CXI->getPointerOperand(); | ||||
181 | } | ||||
182 | |||||
183 | if (auto *RMWI = dyn_cast<AtomicRMWInst>(I)) { | ||||
184 | return RMWI->getPointerOperand(); | ||||
185 | } | ||||
186 | |||||
187 | return nullptr; | ||||
188 | } | ||||
189 | |||||
190 | /// Helper function to create a pointer of type \p ResTy, based on \p Ptr, and | ||||
191 | /// advanced by \p Offset bytes. To aid later analysis the method tries to build | ||||
192 | /// getelement pointer instructions that traverse the natural type of \p Ptr if | ||||
193 | /// possible. If that fails, the remaining offset is adjusted byte-wise, hence | ||||
194 | /// through a cast to i8*. | ||||
195 | /// | ||||
196 | /// TODO: This could probably live somewhere more prominantly if it doesn't | ||||
197 | /// already exist. | ||||
198 | static Value *constructPointer(Type *ResTy, Type *PtrElemTy, Value *Ptr, | ||||
199 | int64_t Offset, IRBuilder<NoFolder> &IRB, | ||||
200 | const DataLayout &DL) { | ||||
201 | assert(Offset >= 0 && "Negative offset not supported yet!")(static_cast<void> (0)); | ||||
202 | LLVM_DEBUG(dbgs() << "Construct pointer: " << *Ptr << " + " << Offsetdo { } while (false) | ||||
203 | << "-bytes as " << *ResTy << "\n")do { } while (false); | ||||
204 | |||||
205 | if (Offset) { | ||||
206 | SmallVector<Value *, 4> Indices; | ||||
207 | std::string GEPName = Ptr->getName().str() + ".0"; | ||||
208 | |||||
209 | // Add 0 index to look through the pointer. | ||||
210 | assert((uint64_t)Offset < DL.getTypeAllocSize(PtrElemTy) &&(static_cast<void> (0)) | ||||
211 | "Offset out of bounds")(static_cast<void> (0)); | ||||
212 | Indices.push_back(Constant::getNullValue(IRB.getInt32Ty())); | ||||
213 | |||||
214 | Type *Ty = PtrElemTy; | ||||
215 | do { | ||||
216 | auto *STy = dyn_cast<StructType>(Ty); | ||||
217 | if (!STy) | ||||
218 | // Non-aggregate type, we cast and make byte-wise progress now. | ||||
219 | break; | ||||
220 | |||||
221 | const StructLayout *SL = DL.getStructLayout(STy); | ||||
222 | if (int64_t(SL->getSizeInBytes()) < Offset) | ||||
223 | break; | ||||
224 | |||||
225 | uint64_t Idx = SL->getElementContainingOffset(Offset); | ||||
226 | assert(Idx < STy->getNumElements() && "Offset calculation error!")(static_cast<void> (0)); | ||||
227 | uint64_t Rem = Offset - SL->getElementOffset(Idx); | ||||
228 | Ty = STy->getElementType(Idx); | ||||
229 | |||||
230 | LLVM_DEBUG(errs() << "Ty: " << *Ty << " Offset: " << Offsetdo { } while (false) | ||||
231 | << " Idx: " << Idx << " Rem: " << Rem << "\n")do { } while (false); | ||||
232 | |||||
233 | GEPName += "." + std::to_string(Idx); | ||||
234 | Indices.push_back(ConstantInt::get(IRB.getInt32Ty(), Idx)); | ||||
235 | Offset = Rem; | ||||
236 | } while (Offset); | ||||
237 | |||||
238 | // Create a GEP for the indices collected above. | ||||
239 | Ptr = IRB.CreateGEP(PtrElemTy, Ptr, Indices, GEPName); | ||||
240 | |||||
241 | // If an offset is left we use byte-wise adjustment. | ||||
242 | if (Offset) { | ||||
243 | Ptr = IRB.CreateBitCast(Ptr, IRB.getInt8PtrTy()); | ||||
244 | Ptr = IRB.CreateGEP(IRB.getInt8Ty(), Ptr, IRB.getInt32(Offset), | ||||
245 | GEPName + ".b" + Twine(Offset)); | ||||
246 | } | ||||
247 | } | ||||
248 | |||||
249 | // Ensure the result has the requested type. | ||||
250 | Ptr = IRB.CreateBitOrPointerCast(Ptr, ResTy, Ptr->getName() + ".cast"); | ||||
251 | |||||
252 | LLVM_DEBUG(dbgs() << "Constructed pointer: " << *Ptr << "\n")do { } while (false); | ||||
253 | return Ptr; | ||||
254 | } | ||||
255 | |||||
256 | /// Recursively visit all values that might become \p IRP at some point. This | ||||
257 | /// will be done by looking through cast instructions, selects, phis, and calls | ||||
258 | /// with the "returned" attribute. Once we cannot look through the value any | ||||
259 | /// further, the callback \p VisitValueCB is invoked and passed the current | ||||
260 | /// value, the \p State, and a flag to indicate if we stripped anything. | ||||
261 | /// Stripped means that we unpacked the value associated with \p IRP at least | ||||
262 | /// once. Note that the value used for the callback may still be the value | ||||
263 | /// associated with \p IRP (due to PHIs). To limit how much effort is invested, | ||||
264 | /// we will never visit more values than specified by \p MaxValues. | ||||
265 | template <typename StateTy> | ||||
266 | static bool genericValueTraversal( | ||||
267 | Attributor &A, IRPosition IRP, const AbstractAttribute &QueryingAA, | ||||
268 | StateTy &State, | ||||
269 | function_ref<bool(Value &, const Instruction *, StateTy &, bool)> | ||||
270 | VisitValueCB, | ||||
271 | const Instruction *CtxI, bool UseValueSimplify = true, int MaxValues = 16, | ||||
272 | function_ref<Value *(Value *)> StripCB = nullptr) { | ||||
273 | |||||
274 | const AAIsDead *LivenessAA = nullptr; | ||||
275 | if (IRP.getAnchorScope()) | ||||
276 | LivenessAA = &A.getAAFor<AAIsDead>( | ||||
277 | QueryingAA, | ||||
278 | IRPosition::function(*IRP.getAnchorScope(), IRP.getCallBaseContext()), | ||||
279 | DepClassTy::NONE); | ||||
280 | bool AnyDead = false; | ||||
281 | |||||
282 | Value *InitialV = &IRP.getAssociatedValue(); | ||||
283 | using Item = std::pair<Value *, const Instruction *>; | ||||
284 | SmallSet<Item, 16> Visited; | ||||
285 | SmallVector<Item, 16> Worklist; | ||||
286 | Worklist.push_back({InitialV, CtxI}); | ||||
287 | |||||
288 | int Iteration = 0; | ||||
289 | do { | ||||
290 | Item I = Worklist.pop_back_val(); | ||||
291 | Value *V = I.first; | ||||
292 | CtxI = I.second; | ||||
293 | if (StripCB) | ||||
294 | V = StripCB(V); | ||||
295 | |||||
296 | // Check if we should process the current value. To prevent endless | ||||
297 | // recursion keep a record of the values we followed! | ||||
298 | if (!Visited.insert(I).second) | ||||
299 | continue; | ||||
300 | |||||
301 | // Make sure we limit the compile time for complex expressions. | ||||
302 | if (Iteration++ >= MaxValues) | ||||
303 | return false; | ||||
304 | |||||
305 | // Explicitly look through calls with a "returned" attribute if we do | ||||
306 | // not have a pointer as stripPointerCasts only works on them. | ||||
307 | Value *NewV = nullptr; | ||||
308 | if (V->getType()->isPointerTy()) { | ||||
309 | NewV = V->stripPointerCasts(); | ||||
310 | } else { | ||||
311 | auto *CB = dyn_cast<CallBase>(V); | ||||
312 | if (CB
| ||||
313 | for (Argument &Arg : CB->getCalledFunction()->args()) | ||||
314 | if (Arg.hasReturnedAttr()) { | ||||
315 | NewV = CB->getArgOperand(Arg.getArgNo()); | ||||
316 | break; | ||||
317 | } | ||||
318 | } | ||||
319 | } | ||||
320 | if (NewV
| ||||
321 | Worklist.push_back({NewV, CtxI}); | ||||
322 | continue; | ||||
323 | } | ||||
324 | |||||
325 | // Look through select instructions, visit assumed potential values. | ||||
326 | if (auto *SI
| ||||
327 | bool UsedAssumedInformation = false; | ||||
328 | Optional<Constant *> C = A.getAssumedConstant( | ||||
329 | *SI->getCondition(), QueryingAA, UsedAssumedInformation); | ||||
330 | bool NoValueYet = !C.hasValue(); | ||||
331 | if (NoValueYet || isa_and_nonnull<UndefValue>(*C)) | ||||
332 | continue; | ||||
333 | if (auto *CI = dyn_cast_or_null<ConstantInt>(*C)) { | ||||
334 | if (CI->isZero()) | ||||
335 | Worklist.push_back({SI->getFalseValue(), CtxI}); | ||||
336 | else | ||||
337 | Worklist.push_back({SI->getTrueValue(), CtxI}); | ||||
338 | continue; | ||||
339 | } | ||||
340 | // We could not simplify the condition, assume both values.( | ||||
341 | Worklist.push_back({SI->getTrueValue(), CtxI}); | ||||
342 | Worklist.push_back({SI->getFalseValue(), CtxI}); | ||||
343 | continue; | ||||
344 | } | ||||
345 | |||||
346 | // Look through phi nodes, visit all live operands. | ||||
347 | if (auto *PHI
| ||||
348 | assert(LivenessAA &&(static_cast<void> (0)) | ||||
349 | "Expected liveness in the presence of instructions!")(static_cast<void> (0)); | ||||
350 | for (unsigned u = 0, e = PHI->getNumIncomingValues(); u < e; u++) { | ||||
351 | BasicBlock *IncomingBB = PHI->getIncomingBlock(u); | ||||
352 | bool UsedAssumedInformation = false; | ||||
353 | if (A.isAssumedDead(*IncomingBB->getTerminator(), &QueryingAA, | ||||
354 | LivenessAA, UsedAssumedInformation, | ||||
355 | /* CheckBBLivenessOnly */ true)) { | ||||
356 | AnyDead = true; | ||||
357 | continue; | ||||
358 | } | ||||
359 | Worklist.push_back( | ||||
360 | {PHI->getIncomingValue(u), IncomingBB->getTerminator()}); | ||||
361 | } | ||||
362 | continue; | ||||
363 | } | ||||
364 | |||||
365 | if (UseValueSimplify && !isa<Constant>(V)) { | ||||
366 | bool UsedAssumedInformation = false; | ||||
367 | Optional<Value *> SimpleV = | ||||
368 | A.getAssumedSimplified(*V, QueryingAA, UsedAssumedInformation); | ||||
369 | if (!SimpleV.hasValue()) | ||||
370 | continue; | ||||
371 | if (!SimpleV.getValue()) | ||||
372 | return false; | ||||
373 | Value *NewV = SimpleV.getValue(); | ||||
374 | if (NewV != V) { | ||||
375 | Worklist.push_back({NewV, CtxI}); | ||||
376 | continue; | ||||
377 | } | ||||
378 | } | ||||
379 | |||||
380 | // Once a leaf is reached we inform the user through the callback. | ||||
381 | if (!VisitValueCB(*V, CtxI, State, Iteration > 1)) | ||||
382 | return false; | ||||
383 | } while (!Worklist.empty()); | ||||
384 | |||||
385 | // If we actually used liveness information so we have to record a dependence. | ||||
386 | if (AnyDead
| ||||
387 | A.recordDependence(*LivenessAA, QueryingAA, DepClassTy::OPTIONAL); | ||||
| |||||
388 | |||||
389 | // All values have been visited. | ||||
390 | return true; | ||||
391 | } | ||||
392 | |||||
393 | bool AA::getAssumedUnderlyingObjects(Attributor &A, const Value &Ptr, | ||||
394 | SmallVectorImpl<Value *> &Objects, | ||||
395 | const AbstractAttribute &QueryingAA, | ||||
396 | const Instruction *CtxI) { | ||||
397 | auto StripCB = [&](Value *V) { return getUnderlyingObject(V); }; | ||||
398 | SmallPtrSet<Value *, 8> SeenObjects; | ||||
399 | auto VisitValueCB = [&SeenObjects](Value &Val, const Instruction *, | ||||
400 | SmallVectorImpl<Value *> &Objects, | ||||
401 | bool) -> bool { | ||||
402 | if (SeenObjects.insert(&Val).second) | ||||
403 | Objects.push_back(&Val); | ||||
404 | return true; | ||||
405 | }; | ||||
406 | if (!genericValueTraversal<decltype(Objects)>( | ||||
407 | A, IRPosition::value(Ptr), QueryingAA, Objects, VisitValueCB, CtxI, | ||||
408 | true, 32, StripCB)) | ||||
409 | return false; | ||||
410 | return true; | ||||
411 | } | ||||
412 | |||||
413 | const Value *stripAndAccumulateMinimalOffsets( | ||||
414 | Attributor &A, const AbstractAttribute &QueryingAA, const Value *Val, | ||||
415 | const DataLayout &DL, APInt &Offset, bool AllowNonInbounds, | ||||
416 | bool UseAssumed = false) { | ||||
417 | |||||
418 | auto AttributorAnalysis = [&](Value &V, APInt &ROffset) -> bool { | ||||
419 | const IRPosition &Pos = IRPosition::value(V); | ||||
420 | // Only track dependence if we are going to use the assumed info. | ||||
421 | const AAValueConstantRange &ValueConstantRangeAA = | ||||
422 | A.getAAFor<AAValueConstantRange>(QueryingAA, Pos, | ||||
423 | UseAssumed ? DepClassTy::OPTIONAL | ||||
424 | : DepClassTy::NONE); | ||||
425 | ConstantRange Range = UseAssumed ? ValueConstantRangeAA.getAssumed() | ||||
426 | : ValueConstantRangeAA.getKnown(); | ||||
427 | // We can only use the lower part of the range because the upper part can | ||||
428 | // be higher than what the value can really be. | ||||
429 | ROffset = Range.getSignedMin(); | ||||
430 | return true; | ||||
431 | }; | ||||
432 | |||||
433 | return Val->stripAndAccumulateConstantOffsets(DL, Offset, AllowNonInbounds, | ||||
434 | AttributorAnalysis); | ||||
435 | } | ||||
436 | |||||
437 | static const Value *getMinimalBaseOfAccsesPointerOperand( | ||||
438 | Attributor &A, const AbstractAttribute &QueryingAA, const Instruction *I, | ||||
439 | int64_t &BytesOffset, const DataLayout &DL, bool AllowNonInbounds = false) { | ||||
440 | const Value *Ptr = getPointerOperand(I, /* AllowVolatile */ false); | ||||
441 | if (!Ptr) | ||||
442 | return nullptr; | ||||
443 | APInt OffsetAPInt(DL.getIndexTypeSizeInBits(Ptr->getType()), 0); | ||||
444 | const Value *Base = stripAndAccumulateMinimalOffsets( | ||||
445 | A, QueryingAA, Ptr, DL, OffsetAPInt, AllowNonInbounds); | ||||
446 | |||||
447 | BytesOffset = OffsetAPInt.getSExtValue(); | ||||
448 | return Base; | ||||
449 | } | ||||
450 | |||||
451 | static const Value * | ||||
452 | getBasePointerOfAccessPointerOperand(const Instruction *I, int64_t &BytesOffset, | ||||
453 | const DataLayout &DL, | ||||
454 | bool AllowNonInbounds = false) { | ||||
455 | const Value *Ptr = getPointerOperand(I, /* AllowVolatile */ false); | ||||
456 | if (!Ptr) | ||||
457 | return nullptr; | ||||
458 | |||||
459 | return GetPointerBaseWithConstantOffset(Ptr, BytesOffset, DL, | ||||
460 | AllowNonInbounds); | ||||
461 | } | ||||
462 | |||||
463 | /// Clamp the information known for all returned values of a function | ||||
464 | /// (identified by \p QueryingAA) into \p S. | ||||
465 | template <typename AAType, typename StateType = typename AAType::StateType> | ||||
466 | static void clampReturnedValueStates( | ||||
467 | Attributor &A, const AAType &QueryingAA, StateType &S, | ||||
468 | const IRPosition::CallBaseContext *CBContext = nullptr) { | ||||
469 | LLVM_DEBUG(dbgs() << "[Attributor] Clamp return value states for "do { } while (false) | ||||
470 | << QueryingAA << " into " << S << "\n")do { } while (false); | ||||
471 | |||||
472 | assert((QueryingAA.getIRPosition().getPositionKind() ==(static_cast<void> (0)) | ||||
473 | IRPosition::IRP_RETURNED ||(static_cast<void> (0)) | ||||
474 | QueryingAA.getIRPosition().getPositionKind() ==(static_cast<void> (0)) | ||||
475 | IRPosition::IRP_CALL_SITE_RETURNED) &&(static_cast<void> (0)) | ||||
476 | "Can only clamp returned value states for a function returned or call "(static_cast<void> (0)) | ||||
477 | "site returned position!")(static_cast<void> (0)); | ||||
478 | |||||
479 | // Use an optional state as there might not be any return values and we want | ||||
480 | // to join (IntegerState::operator&) the state of all there are. | ||||
481 | Optional<StateType> T; | ||||
482 | |||||
483 | // Callback for each possibly returned value. | ||||
484 | auto CheckReturnValue = [&](Value &RV) -> bool { | ||||
485 | const IRPosition &RVPos = IRPosition::value(RV, CBContext); | ||||
486 | const AAType &AA = | ||||
487 | A.getAAFor<AAType>(QueryingAA, RVPos, DepClassTy::REQUIRED); | ||||
488 | LLVM_DEBUG(dbgs() << "[Attributor] RV: " << RV << " AA: " << AA.getAsStr()do { } while (false) | ||||
489 | << " @ " << RVPos << "\n")do { } while (false); | ||||
490 | const StateType &AAS = AA.getState(); | ||||
491 | if (T.hasValue()) | ||||
492 | *T &= AAS; | ||||
493 | else | ||||
494 | T = AAS; | ||||
495 | LLVM_DEBUG(dbgs() << "[Attributor] AA State: " << AAS << " RV State: " << Tdo { } while (false) | ||||
496 | << "\n")do { } while (false); | ||||
497 | return T->isValidState(); | ||||
498 | }; | ||||
499 | |||||
500 | if (!A.checkForAllReturnedValues(CheckReturnValue, QueryingAA)) | ||||
501 | S.indicatePessimisticFixpoint(); | ||||
502 | else if (T.hasValue()) | ||||
503 | S ^= *T; | ||||
504 | } | ||||
505 | |||||
506 | /// Helper class for generic deduction: return value -> returned position. | ||||
507 | template <typename AAType, typename BaseType, | ||||
508 | typename StateType = typename BaseType::StateType, | ||||
509 | bool PropagateCallBaseContext = false> | ||||
510 | struct AAReturnedFromReturnedValues : public BaseType { | ||||
511 | AAReturnedFromReturnedValues(const IRPosition &IRP, Attributor &A) | ||||
512 | : BaseType(IRP, A) {} | ||||
513 | |||||
514 | /// See AbstractAttribute::updateImpl(...). | ||||
515 | ChangeStatus updateImpl(Attributor &A) override { | ||||
516 | StateType S(StateType::getBestState(this->getState())); | ||||
517 | clampReturnedValueStates<AAType, StateType>( | ||||
518 | A, *this, S, | ||||
519 | PropagateCallBaseContext ? this->getCallBaseContext() : nullptr); | ||||
520 | // TODO: If we know we visited all returned values, thus no are assumed | ||||
521 | // dead, we can take the known information from the state T. | ||||
522 | return clampStateAndIndicateChange<StateType>(this->getState(), S); | ||||
523 | } | ||||
524 | }; | ||||
525 | |||||
526 | /// Clamp the information known at all call sites for a given argument | ||||
527 | /// (identified by \p QueryingAA) into \p S. | ||||
528 | template <typename AAType, typename StateType = typename AAType::StateType> | ||||
529 | static void clampCallSiteArgumentStates(Attributor &A, const AAType &QueryingAA, | ||||
530 | StateType &S) { | ||||
531 | LLVM_DEBUG(dbgs() << "[Attributor] Clamp call site argument states for "do { } while (false) | ||||
532 | << QueryingAA << " into " << S << "\n")do { } while (false); | ||||
533 | |||||
534 | assert(QueryingAA.getIRPosition().getPositionKind() ==(static_cast<void> (0)) | ||||
535 | IRPosition::IRP_ARGUMENT &&(static_cast<void> (0)) | ||||
536 | "Can only clamp call site argument states for an argument position!")(static_cast<void> (0)); | ||||
537 | |||||
538 | // Use an optional state as there might not be any return values and we want | ||||
539 | // to join (IntegerState::operator&) the state of all there are. | ||||
540 | Optional<StateType> T; | ||||
541 | |||||
542 | // The argument number which is also the call site argument number. | ||||
543 | unsigned ArgNo = QueryingAA.getIRPosition().getCallSiteArgNo(); | ||||
544 | |||||
545 | auto CallSiteCheck = [&](AbstractCallSite ACS) { | ||||
546 | const IRPosition &ACSArgPos = IRPosition::callsite_argument(ACS, ArgNo); | ||||
547 | // Check if a coresponding argument was found or if it is on not associated | ||||
548 | // (which can happen for callback calls). | ||||
549 | if (ACSArgPos.getPositionKind() == IRPosition::IRP_INVALID) | ||||
550 | return false; | ||||
551 | |||||
552 | const AAType &AA = | ||||
553 | A.getAAFor<AAType>(QueryingAA, ACSArgPos, DepClassTy::REQUIRED); | ||||
554 | LLVM_DEBUG(dbgs() << "[Attributor] ACS: " << *ACS.getInstruction()do { } while (false) | ||||
555 | << " AA: " << AA.getAsStr() << " @" << ACSArgPos << "\n")do { } while (false); | ||||
556 | const StateType &AAS = AA.getState(); | ||||
557 | if (T.hasValue()) | ||||
558 | *T &= AAS; | ||||
559 | else | ||||
560 | T = AAS; | ||||
561 | LLVM_DEBUG(dbgs() << "[Attributor] AA State: " << AAS << " CSA State: " << Tdo { } while (false) | ||||
562 | << "\n")do { } while (false); | ||||
563 | return T->isValidState(); | ||||
564 | }; | ||||
565 | |||||
566 | bool AllCallSitesKnown; | ||||
567 | if (!A.checkForAllCallSites(CallSiteCheck, QueryingAA, true, | ||||
568 | AllCallSitesKnown)) | ||||
569 | S.indicatePessimisticFixpoint(); | ||||
570 | else if (T.hasValue()) | ||||
571 | S ^= *T; | ||||
572 | } | ||||
573 | |||||
574 | /// This function is the bridge between argument position and the call base | ||||
575 | /// context. | ||||
576 | template <typename AAType, typename BaseType, | ||||
577 | typename StateType = typename AAType::StateType> | ||||
578 | bool getArgumentStateFromCallBaseContext(Attributor &A, | ||||
579 | BaseType &QueryingAttribute, | ||||
580 | IRPosition &Pos, StateType &State) { | ||||
581 | assert((Pos.getPositionKind() == IRPosition::IRP_ARGUMENT) &&(static_cast<void> (0)) | ||||
582 | "Expected an 'argument' position !")(static_cast<void> (0)); | ||||
583 | const CallBase *CBContext = Pos.getCallBaseContext(); | ||||
584 | if (!CBContext) | ||||
585 | return false; | ||||
586 | |||||
587 | int ArgNo = Pos.getCallSiteArgNo(); | ||||
588 | assert(ArgNo >= 0 && "Invalid Arg No!")(static_cast<void> (0)); | ||||
589 | |||||
590 | const auto &AA = A.getAAFor<AAType>( | ||||
591 | QueryingAttribute, IRPosition::callsite_argument(*CBContext, ArgNo), | ||||
592 | DepClassTy::REQUIRED); | ||||
593 | const StateType &CBArgumentState = | ||||
594 | static_cast<const StateType &>(AA.getState()); | ||||
595 | |||||
596 | LLVM_DEBUG(dbgs() << "[Attributor] Briding Call site context to argument"do { } while (false) | ||||
597 | << "Position:" << Pos << "CB Arg state:" << CBArgumentStatedo { } while (false) | ||||
598 | << "\n")do { } while (false); | ||||
599 | |||||
600 | // NOTE: If we want to do call site grouping it should happen here. | ||||
601 | State ^= CBArgumentState; | ||||
602 | return true; | ||||
603 | } | ||||
604 | |||||
605 | /// Helper class for generic deduction: call site argument -> argument position. | ||||
606 | template <typename AAType, typename BaseType, | ||||
607 | typename StateType = typename AAType::StateType, | ||||
608 | bool BridgeCallBaseContext = false> | ||||
609 | struct AAArgumentFromCallSiteArguments : public BaseType { | ||||
610 | AAArgumentFromCallSiteArguments(const IRPosition &IRP, Attributor &A) | ||||
611 | : BaseType(IRP, A) {} | ||||
612 | |||||
613 | /// See AbstractAttribute::updateImpl(...). | ||||
614 | ChangeStatus updateImpl(Attributor &A) override { | ||||
615 | StateType S = StateType::getBestState(this->getState()); | ||||
616 | |||||
617 | if (BridgeCallBaseContext) { | ||||
618 | bool Success = | ||||
619 | getArgumentStateFromCallBaseContext<AAType, BaseType, StateType>( | ||||
620 | A, *this, this->getIRPosition(), S); | ||||
621 | if (Success) | ||||
622 | return clampStateAndIndicateChange<StateType>(this->getState(), S); | ||||
623 | } | ||||
624 | clampCallSiteArgumentStates<AAType, StateType>(A, *this, S); | ||||
625 | |||||
626 | // TODO: If we know we visited all incoming values, thus no are assumed | ||||
627 | // dead, we can take the known information from the state T. | ||||
628 | return clampStateAndIndicateChange<StateType>(this->getState(), S); | ||||
629 | } | ||||
630 | }; | ||||
631 | |||||
632 | /// Helper class for generic replication: function returned -> cs returned. | ||||
633 | template <typename AAType, typename BaseType, | ||||
634 | typename StateType = typename BaseType::StateType, | ||||
635 | bool IntroduceCallBaseContext = false> | ||||
636 | struct AACallSiteReturnedFromReturned : public BaseType { | ||||
637 | AACallSiteReturnedFromReturned(const IRPosition &IRP, Attributor &A) | ||||
638 | : BaseType(IRP, A) {} | ||||
639 | |||||
640 | /// See AbstractAttribute::updateImpl(...). | ||||
641 | ChangeStatus updateImpl(Attributor &A) override { | ||||
642 | assert(this->getIRPosition().getPositionKind() ==(static_cast<void> (0)) | ||||
643 | IRPosition::IRP_CALL_SITE_RETURNED &&(static_cast<void> (0)) | ||||
644 | "Can only wrap function returned positions for call site returned "(static_cast<void> (0)) | ||||
645 | "positions!")(static_cast<void> (0)); | ||||
646 | auto &S = this->getState(); | ||||
647 | |||||
648 | const Function *AssociatedFunction = | ||||
649 | this->getIRPosition().getAssociatedFunction(); | ||||
650 | if (!AssociatedFunction) | ||||
651 | return S.indicatePessimisticFixpoint(); | ||||
652 | |||||
653 | CallBase &CBContext = static_cast<CallBase &>(this->getAnchorValue()); | ||||
654 | if (IntroduceCallBaseContext) | ||||
655 | LLVM_DEBUG(dbgs() << "[Attributor] Introducing call base context:"do { } while (false) | ||||
656 | << CBContext << "\n")do { } while (false); | ||||
657 | |||||
658 | IRPosition FnPos = IRPosition::returned( | ||||
659 | *AssociatedFunction, IntroduceCallBaseContext ? &CBContext : nullptr); | ||||
660 | const AAType &AA = A.getAAFor<AAType>(*this, FnPos, DepClassTy::REQUIRED); | ||||
661 | return clampStateAndIndicateChange(S, AA.getState()); | ||||
662 | } | ||||
663 | }; | ||||
664 | |||||
665 | /// Helper function to accumulate uses. | ||||
666 | template <class AAType, typename StateType = typename AAType::StateType> | ||||
667 | static void followUsesInContext(AAType &AA, Attributor &A, | ||||
668 | MustBeExecutedContextExplorer &Explorer, | ||||
669 | const Instruction *CtxI, | ||||
670 | SetVector<const Use *> &Uses, | ||||
671 | StateType &State) { | ||||
672 | auto EIt = Explorer.begin(CtxI), EEnd = Explorer.end(CtxI); | ||||
673 | for (unsigned u = 0; u < Uses.size(); ++u) { | ||||
674 | const Use *U = Uses[u]; | ||||
675 | if (const Instruction *UserI = dyn_cast<Instruction>(U->getUser())) { | ||||
676 | bool Found = Explorer.findInContextOf(UserI, EIt, EEnd); | ||||
677 | if (Found && AA.followUseInMBEC(A, U, UserI, State)) | ||||
678 | for (const Use &Us : UserI->uses()) | ||||
679 | Uses.insert(&Us); | ||||
680 | } | ||||
681 | } | ||||
682 | } | ||||
683 | |||||
684 | /// Use the must-be-executed-context around \p I to add information into \p S. | ||||
685 | /// The AAType class is required to have `followUseInMBEC` method with the | ||||
686 | /// following signature and behaviour: | ||||
687 | /// | ||||
688 | /// bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I) | ||||
689 | /// U - Underlying use. | ||||
690 | /// I - The user of the \p U. | ||||
691 | /// Returns true if the value should be tracked transitively. | ||||
692 | /// | ||||
693 | template <class AAType, typename StateType = typename AAType::StateType> | ||||
694 | static void followUsesInMBEC(AAType &AA, Attributor &A, StateType &S, | ||||
695 | Instruction &CtxI) { | ||||
696 | |||||
697 | // Container for (transitive) uses of the associated value. | ||||
698 | SetVector<const Use *> Uses; | ||||
699 | for (const Use &U : AA.getIRPosition().getAssociatedValue().uses()) | ||||
700 | Uses.insert(&U); | ||||
701 | |||||
702 | MustBeExecutedContextExplorer &Explorer = | ||||
703 | A.getInfoCache().getMustBeExecutedContextExplorer(); | ||||
704 | |||||
705 | followUsesInContext<AAType>(AA, A, Explorer, &CtxI, Uses, S); | ||||
706 | |||||
707 | if (S.isAtFixpoint()) | ||||
708 | return; | ||||
709 | |||||
710 | SmallVector<const BranchInst *, 4> BrInsts; | ||||
711 | auto Pred = [&](const Instruction *I) { | ||||
712 | if (const BranchInst *Br = dyn_cast<BranchInst>(I)) | ||||
713 | if (Br->isConditional()) | ||||
714 | BrInsts.push_back(Br); | ||||
715 | return true; | ||||
716 | }; | ||||
717 | |||||
718 | // Here, accumulate conditional branch instructions in the context. We | ||||
719 | // explore the child paths and collect the known states. The disjunction of | ||||
720 | // those states can be merged to its own state. Let ParentState_i be a state | ||||
721 | // to indicate the known information for an i-th branch instruction in the | ||||
722 | // context. ChildStates are created for its successors respectively. | ||||
723 | // | ||||
724 | // ParentS_1 = ChildS_{1, 1} /\ ChildS_{1, 2} /\ ... /\ ChildS_{1, n_1} | ||||
725 | // ParentS_2 = ChildS_{2, 1} /\ ChildS_{2, 2} /\ ... /\ ChildS_{2, n_2} | ||||
726 | // ... | ||||
727 | // ParentS_m = ChildS_{m, 1} /\ ChildS_{m, 2} /\ ... /\ ChildS_{m, n_m} | ||||
728 | // | ||||
729 | // Known State |= ParentS_1 \/ ParentS_2 \/... \/ ParentS_m | ||||
730 | // | ||||
731 | // FIXME: Currently, recursive branches are not handled. For example, we | ||||
732 | // can't deduce that ptr must be dereferenced in below function. | ||||
733 | // | ||||
734 | // void f(int a, int c, int *ptr) { | ||||
735 | // if(a) | ||||
736 | // if (b) { | ||||
737 | // *ptr = 0; | ||||
738 | // } else { | ||||
739 | // *ptr = 1; | ||||
740 | // } | ||||
741 | // else { | ||||
742 | // if (b) { | ||||
743 | // *ptr = 0; | ||||
744 | // } else { | ||||
745 | // *ptr = 1; | ||||
746 | // } | ||||
747 | // } | ||||
748 | // } | ||||
749 | |||||
750 | Explorer.checkForAllContext(&CtxI, Pred); | ||||
751 | for (const BranchInst *Br : BrInsts) { | ||||
752 | StateType ParentState; | ||||
753 | |||||
754 | // The known state of the parent state is a conjunction of children's | ||||
755 | // known states so it is initialized with a best state. | ||||
756 | ParentState.indicateOptimisticFixpoint(); | ||||
757 | |||||
758 | for (const BasicBlock *BB : Br->successors()) { | ||||
759 | StateType ChildState; | ||||
760 | |||||
761 | size_t BeforeSize = Uses.size(); | ||||
762 | followUsesInContext(AA, A, Explorer, &BB->front(), Uses, ChildState); | ||||
763 | |||||
764 | // Erase uses which only appear in the child. | ||||
765 | for (auto It = Uses.begin() + BeforeSize; It != Uses.end();) | ||||
766 | It = Uses.erase(It); | ||||
767 | |||||
768 | ParentState &= ChildState; | ||||
769 | } | ||||
770 | |||||
771 | // Use only known state. | ||||
772 | S += ParentState; | ||||
773 | } | ||||
774 | } | ||||
775 | |||||
776 | /// ------------------------ PointerInfo --------------------------------------- | ||||
777 | |||||
778 | namespace llvm { | ||||
779 | namespace AA { | ||||
780 | namespace PointerInfo { | ||||
781 | |||||
782 | /// An access kind description as used by AAPointerInfo. | ||||
783 | struct OffsetAndSize; | ||||
784 | |||||
785 | struct State; | ||||
786 | |||||
787 | } // namespace PointerInfo | ||||
788 | } // namespace AA | ||||
789 | |||||
790 | /// Helper for AA::PointerInfo::Acccess DenseMap/Set usage. | ||||
791 | template <> | ||||
792 | struct DenseMapInfo<AAPointerInfo::Access> : DenseMapInfo<Instruction *> { | ||||
793 | using Access = AAPointerInfo::Access; | ||||
794 | static inline Access getEmptyKey(); | ||||
795 | static inline Access getTombstoneKey(); | ||||
796 | static unsigned getHashValue(const Access &A); | ||||
797 | static bool isEqual(const Access &LHS, const Access &RHS); | ||||
798 | }; | ||||
799 | |||||
800 | /// Helper that allows OffsetAndSize as a key in a DenseMap. | ||||
801 | template <> | ||||
802 | struct DenseMapInfo<AA::PointerInfo ::OffsetAndSize> | ||||
803 | : DenseMapInfo<std::pair<int64_t, int64_t>> {}; | ||||
804 | |||||
805 | /// Helper for AA::PointerInfo::Acccess DenseMap/Set usage ignoring everythign | ||||
806 | /// but the instruction | ||||
807 | struct AccessAsInstructionInfo : DenseMapInfo<Instruction *> { | ||||
808 | using Base = DenseMapInfo<Instruction *>; | ||||
809 | using Access = AAPointerInfo::Access; | ||||
810 | static inline Access getEmptyKey(); | ||||
811 | static inline Access getTombstoneKey(); | ||||
812 | static unsigned getHashValue(const Access &A); | ||||
813 | static bool isEqual(const Access &LHS, const Access &RHS); | ||||
814 | }; | ||||
815 | |||||
816 | } // namespace llvm | ||||
817 | |||||
818 | /// Helper to represent an access offset and size, with logic to deal with | ||||
819 | /// uncertainty and check for overlapping accesses. | ||||
820 | struct AA::PointerInfo::OffsetAndSize : public std::pair<int64_t, int64_t> { | ||||
821 | using BaseTy = std::pair<int64_t, int64_t>; | ||||
822 | OffsetAndSize(int64_t Offset, int64_t Size) : BaseTy(Offset, Size) {} | ||||
823 | OffsetAndSize(const BaseTy &P) : BaseTy(P) {} | ||||
824 | int64_t getOffset() const { return first; } | ||||
825 | int64_t getSize() const { return second; } | ||||
826 | static OffsetAndSize getUnknown() { return OffsetAndSize(Unknown, Unknown); } | ||||
827 | |||||
828 | /// Return true if this offset and size pair might describe an address that | ||||
829 | /// overlaps with \p OAS. | ||||
830 | bool mayOverlap(const OffsetAndSize &OAS) const { | ||||
831 | // Any unknown value and we are giving up -> overlap. | ||||
832 | if (OAS.getOffset() == OffsetAndSize::Unknown || | ||||
833 | OAS.getSize() == OffsetAndSize::Unknown || | ||||
834 | getOffset() == OffsetAndSize::Unknown || | ||||
835 | getSize() == OffsetAndSize::Unknown) | ||||
836 | return true; | ||||
837 | |||||
838 | // Check if one offset point is in the other interval [offset, offset+size]. | ||||
839 | return OAS.getOffset() + OAS.getSize() > getOffset() && | ||||
840 | OAS.getOffset() < getOffset() + getSize(); | ||||
841 | } | ||||
842 | |||||
843 | /// Constant used to represent unknown offset or sizes. | ||||
844 | static constexpr int64_t Unknown = 1 << 31; | ||||
845 | }; | ||||
846 | |||||
847 | /// Implementation of the DenseMapInfo. | ||||
848 | /// | ||||
849 | ///{ | ||||
850 | inline llvm::AccessAsInstructionInfo::Access | ||||
851 | llvm::AccessAsInstructionInfo::getEmptyKey() { | ||||
852 | return Access(Base::getEmptyKey(), nullptr, AAPointerInfo::AK_READ, nullptr); | ||||
853 | } | ||||
854 | inline llvm::AccessAsInstructionInfo::Access | ||||
855 | llvm::AccessAsInstructionInfo::getTombstoneKey() { | ||||
856 | return Access(Base::getTombstoneKey(), nullptr, AAPointerInfo::AK_READ, | ||||
857 | nullptr); | ||||
858 | } | ||||
859 | unsigned llvm::AccessAsInstructionInfo::getHashValue( | ||||
860 | const llvm::AccessAsInstructionInfo::Access &A) { | ||||
861 | return Base::getHashValue(A.getRemoteInst()); | ||||
862 | } | ||||
863 | bool llvm::AccessAsInstructionInfo::isEqual( | ||||
864 | const llvm::AccessAsInstructionInfo::Access &LHS, | ||||
865 | const llvm::AccessAsInstructionInfo::Access &RHS) { | ||||
866 | return LHS.getRemoteInst() == RHS.getRemoteInst(); | ||||
867 | } | ||||
868 | inline llvm::DenseMapInfo<AAPointerInfo::Access>::Access | ||||
869 | llvm::DenseMapInfo<AAPointerInfo::Access>::getEmptyKey() { | ||||
870 | return AAPointerInfo::Access(nullptr, nullptr, AAPointerInfo::AK_READ, | ||||
871 | nullptr); | ||||
872 | } | ||||
873 | inline llvm::DenseMapInfo<AAPointerInfo::Access>::Access | ||||
874 | llvm::DenseMapInfo<AAPointerInfo::Access>::getTombstoneKey() { | ||||
875 | return AAPointerInfo::Access(nullptr, nullptr, AAPointerInfo::AK_WRITE, | ||||
876 | nullptr); | ||||
877 | } | ||||
878 | |||||
879 | unsigned llvm::DenseMapInfo<AAPointerInfo::Access>::getHashValue( | ||||
880 | const llvm::DenseMapInfo<AAPointerInfo::Access>::Access &A) { | ||||
881 | return detail::combineHashValue( | ||||
882 | DenseMapInfo<Instruction *>::getHashValue(A.getRemoteInst()), | ||||
883 | (A.isWrittenValueYetUndetermined() | ||||
884 | ? ~0 | ||||
885 | : DenseMapInfo<Value *>::getHashValue(A.getWrittenValue()))) + | ||||
886 | A.getKind(); | ||||
887 | } | ||||
888 | |||||
889 | bool llvm::DenseMapInfo<AAPointerInfo::Access>::isEqual( | ||||
890 | const llvm::DenseMapInfo<AAPointerInfo::Access>::Access &LHS, | ||||
891 | const llvm::DenseMapInfo<AAPointerInfo::Access>::Access &RHS) { | ||||
892 | return LHS == RHS; | ||||
893 | } | ||||
894 | ///} | ||||
895 | |||||
896 | /// A type to track pointer/struct usage and accesses for AAPointerInfo. | ||||
897 | struct AA::PointerInfo::State : public AbstractState { | ||||
898 | |||||
899 | /// Return the best possible representable state. | ||||
900 | static State getBestState(const State &SIS) { return State(); } | ||||
901 | |||||
902 | /// Return the worst possible representable state. | ||||
903 | static State getWorstState(const State &SIS) { | ||||
904 | State R; | ||||
905 | R.indicatePessimisticFixpoint(); | ||||
906 | return R; | ||||
907 | } | ||||
908 | |||||
909 | State() {} | ||||
910 | State(const State &SIS) : AccessBins(SIS.AccessBins) {} | ||||
911 | State(State &&SIS) : AccessBins(std::move(SIS.AccessBins)) {} | ||||
912 | |||||
913 | const State &getAssumed() const { return *this; } | ||||
914 | |||||
915 | /// See AbstractState::isValidState(). | ||||
916 | bool isValidState() const override { return BS.isValidState(); } | ||||
917 | |||||
918 | /// See AbstractState::isAtFixpoint(). | ||||
919 | bool isAtFixpoint() const override { return BS.isAtFixpoint(); } | ||||
920 | |||||
921 | /// See AbstractState::indicateOptimisticFixpoint(). | ||||
922 | ChangeStatus indicateOptimisticFixpoint() override { | ||||
923 | BS.indicateOptimisticFixpoint(); | ||||
924 | return ChangeStatus::UNCHANGED; | ||||
925 | } | ||||
926 | |||||
927 | /// See AbstractState::indicatePessimisticFixpoint(). | ||||
928 | ChangeStatus indicatePessimisticFixpoint() override { | ||||
929 | BS.indicatePessimisticFixpoint(); | ||||
930 | return ChangeStatus::CHANGED; | ||||
931 | } | ||||
932 | |||||
933 | State &operator=(const State &R) { | ||||
934 | if (this == &R) | ||||
935 | return *this; | ||||
936 | BS = R.BS; | ||||
937 | AccessBins = R.AccessBins; | ||||
938 | return *this; | ||||
939 | } | ||||
940 | |||||
941 | State &operator=(State &&R) { | ||||
942 | if (this == &R) | ||||
943 | return *this; | ||||
944 | std::swap(BS, R.BS); | ||||
945 | std::swap(AccessBins, R.AccessBins); | ||||
946 | return *this; | ||||
947 | } | ||||
948 | |||||
949 | bool operator==(const State &R) const { | ||||
950 | if (BS != R.BS) | ||||
951 | return false; | ||||
952 | if (AccessBins.size() != R.AccessBins.size()) | ||||
953 | return false; | ||||
954 | auto It = begin(), RIt = R.begin(), E = end(); | ||||
955 | while (It != E) { | ||||
956 | if (It->getFirst() != RIt->getFirst()) | ||||
957 | return false; | ||||
958 | auto &Accs = It->getSecond(); | ||||
959 | auto &RAccs = RIt->getSecond(); | ||||
960 | if (Accs.size() != RAccs.size()) | ||||
961 | return false; | ||||
962 | auto AccIt = Accs.begin(), RAccIt = RAccs.begin(), AccE = Accs.end(); | ||||
963 | while (AccIt != AccE) { | ||||
964 | if (*AccIt != *RAccIt) | ||||
965 | return false; | ||||
966 | ++AccIt; | ||||
967 | ++RAccIt; | ||||
968 | } | ||||
969 | ++It; | ||||
970 | ++RIt; | ||||
971 | } | ||||
972 | return true; | ||||
973 | } | ||||
974 | bool operator!=(const State &R) const { return !(*this == R); } | ||||
975 | |||||
976 | /// We store accesses in a set with the instruction as key. | ||||
977 | using Accesses = DenseSet<AAPointerInfo::Access, AccessAsInstructionInfo>; | ||||
978 | |||||
979 | /// We store all accesses in bins denoted by their offset and size. | ||||
980 | using AccessBinsTy = DenseMap<OffsetAndSize, Accesses>; | ||||
981 | |||||
982 | AccessBinsTy::const_iterator begin() const { return AccessBins.begin(); } | ||||
983 | AccessBinsTy::const_iterator end() const { return AccessBins.end(); } | ||||
984 | |||||
985 | protected: | ||||
986 | /// The bins with all the accesses for the associated pointer. | ||||
987 | DenseMap<OffsetAndSize, Accesses> AccessBins; | ||||
988 | |||||
989 | /// Add a new access to the state at offset \p Offset and with size \p Size. | ||||
990 | /// The access is associated with \p I, writes \p Content (if anything), and | ||||
991 | /// is of kind \p Kind. | ||||
992 | /// \Returns CHANGED, if the state changed, UNCHANGED otherwise. | ||||
993 | ChangeStatus addAccess(int64_t Offset, int64_t Size, Instruction &I, | ||||
994 | Optional<Value *> Content, | ||||
995 | AAPointerInfo::AccessKind Kind, Type *Ty, | ||||
996 | Instruction *RemoteI = nullptr, | ||||
997 | Accesses *BinPtr = nullptr) { | ||||
998 | OffsetAndSize Key{Offset, Size}; | ||||
999 | Accesses &Bin = BinPtr ? *BinPtr : AccessBins[Key]; | ||||
1000 | AAPointerInfo::Access Acc(&I, RemoteI ? RemoteI : &I, Content, Kind, Ty); | ||||
1001 | // Check if we have an access for this instruction in this bin, if not, | ||||
1002 | // simply add it. | ||||
1003 | auto It = Bin.find(Acc); | ||||
1004 | if (It == Bin.end()) { | ||||
1005 | Bin.insert(Acc); | ||||
1006 | return ChangeStatus::CHANGED; | ||||
1007 | } | ||||
1008 | // If the existing access is the same as then new one, nothing changed. | ||||
1009 | AAPointerInfo::Access Before = *It; | ||||
1010 | // The new one will be combined with the existing one. | ||||
1011 | *It &= Acc; | ||||
1012 | return *It == Before ? ChangeStatus::UNCHANGED : ChangeStatus::CHANGED; | ||||
1013 | } | ||||
1014 | |||||
1015 | /// See AAPointerInfo::forallInterferingAccesses. | ||||
1016 | bool forallInterferingAccesses( | ||||
1017 | Instruction &I, | ||||
1018 | function_ref<bool(const AAPointerInfo::Access &, bool)> CB) const { | ||||
1019 | if (!isValidState()) | ||||
1020 | return false; | ||||
1021 | // First find the offset and size of I. | ||||
1022 | OffsetAndSize OAS(-1, -1); | ||||
1023 | for (auto &It : AccessBins) { | ||||
1024 | for (auto &Access : It.getSecond()) { | ||||
1025 | if (Access.getRemoteInst() == &I) { | ||||
1026 | OAS = It.getFirst(); | ||||
1027 | break; | ||||
1028 | } | ||||
1029 | } | ||||
1030 | if (OAS.getSize() != -1) | ||||
1031 | break; | ||||
1032 | } | ||||
1033 | if (OAS.getSize() == -1) | ||||
1034 | return true; | ||||
1035 | |||||
1036 | // Now that we have an offset and size, find all overlapping ones and use | ||||
1037 | // the callback on the accesses. | ||||
1038 | for (auto &It : AccessBins) { | ||||
1039 | OffsetAndSize ItOAS = It.getFirst(); | ||||
1040 | if (!OAS.mayOverlap(ItOAS)) | ||||
1041 | continue; | ||||
1042 | for (auto &Access : It.getSecond()) | ||||
1043 | if (!CB(Access, OAS == ItOAS)) | ||||
1044 | return false; | ||||
1045 | } | ||||
1046 | return true; | ||||
1047 | } | ||||
1048 | |||||
1049 | private: | ||||
1050 | /// State to track fixpoint and validity. | ||||
1051 | BooleanState BS; | ||||
1052 | }; | ||||
1053 | |||||
1054 | struct AAPointerInfoImpl | ||||
1055 | : public StateWrapper<AA::PointerInfo::State, AAPointerInfo> { | ||||
1056 | using BaseTy = StateWrapper<AA::PointerInfo::State, AAPointerInfo>; | ||||
1057 | AAPointerInfoImpl(const IRPosition &IRP, Attributor &A) : BaseTy(IRP) {} | ||||
1058 | |||||
1059 | /// See AbstractAttribute::initialize(...). | ||||
1060 | void initialize(Attributor &A) override { AAPointerInfo::initialize(A); } | ||||
1061 | |||||
1062 | /// See AbstractAttribute::getAsStr(). | ||||
1063 | const std::string getAsStr() const override { | ||||
1064 | return std::string("PointerInfo ") + | ||||
1065 | (isValidState() ? (std::string("#") + | ||||
1066 | std::to_string(AccessBins.size()) + " bins") | ||||
1067 | : "<invalid>"); | ||||
1068 | } | ||||
1069 | |||||
1070 | /// See AbstractAttribute::manifest(...). | ||||
1071 | ChangeStatus manifest(Attributor &A) override { | ||||
1072 | return AAPointerInfo::manifest(A); | ||||
1073 | } | ||||
1074 | |||||
1075 | bool forallInterferingAccesses( | ||||
1076 | LoadInst &LI, function_ref<bool(const AAPointerInfo::Access &, bool)> CB) | ||||
1077 | const override { | ||||
1078 | return State::forallInterferingAccesses(LI, CB); | ||||
1079 | } | ||||
1080 | bool forallInterferingAccesses( | ||||
1081 | StoreInst &SI, function_ref<bool(const AAPointerInfo::Access &, bool)> CB) | ||||
1082 | const override { | ||||
1083 | return State::forallInterferingAccesses(SI, CB); | ||||
1084 | } | ||||
1085 | |||||
1086 | ChangeStatus translateAndAddCalleeState(Attributor &A, | ||||
1087 | const AAPointerInfo &CalleeAA, | ||||
1088 | int64_t CallArgOffset, CallBase &CB) { | ||||
1089 | using namespace AA::PointerInfo; | ||||
1090 | if (!CalleeAA.getState().isValidState() || !isValidState()) | ||||
1091 | return indicatePessimisticFixpoint(); | ||||
1092 | |||||
1093 | const auto &CalleeImplAA = static_cast<const AAPointerInfoImpl &>(CalleeAA); | ||||
1094 | bool IsByval = CalleeImplAA.getAssociatedArgument()->hasByValAttr(); | ||||
1095 | |||||
1096 | // Combine the accesses bin by bin. | ||||
1097 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
1098 | for (auto &It : CalleeImplAA.getState()) { | ||||
1099 | OffsetAndSize OAS = OffsetAndSize::getUnknown(); | ||||
1100 | if (CallArgOffset != OffsetAndSize::Unknown) | ||||
1101 | OAS = OffsetAndSize(It.first.getOffset() + CallArgOffset, | ||||
1102 | It.first.getSize()); | ||||
1103 | Accesses &Bin = AccessBins[OAS]; | ||||
1104 | for (const AAPointerInfo::Access &RAcc : It.second) { | ||||
1105 | if (IsByval && !RAcc.isRead()) | ||||
1106 | continue; | ||||
1107 | bool UsedAssumedInformation = false; | ||||
1108 | Optional<Value *> Content = A.translateArgumentToCallSiteContent( | ||||
1109 | RAcc.getContent(), CB, *this, UsedAssumedInformation); | ||||
1110 | AccessKind AK = | ||||
1111 | AccessKind(RAcc.getKind() & (IsByval ? AccessKind::AK_READ | ||||
1112 | : AccessKind::AK_READ_WRITE)); | ||||
1113 | Changed = | ||||
1114 | Changed | addAccess(OAS.getOffset(), OAS.getSize(), CB, Content, AK, | ||||
1115 | RAcc.getType(), RAcc.getRemoteInst(), &Bin); | ||||
1116 | } | ||||
1117 | } | ||||
1118 | return Changed; | ||||
1119 | } | ||||
1120 | |||||
1121 | /// Statistic tracking for all AAPointerInfo implementations. | ||||
1122 | /// See AbstractAttribute::trackStatistics(). | ||||
1123 | void trackPointerInfoStatistics(const IRPosition &IRP) const {} | ||||
1124 | }; | ||||
1125 | |||||
1126 | struct AAPointerInfoFloating : public AAPointerInfoImpl { | ||||
1127 | using AccessKind = AAPointerInfo::AccessKind; | ||||
1128 | AAPointerInfoFloating(const IRPosition &IRP, Attributor &A) | ||||
1129 | : AAPointerInfoImpl(IRP, A) {} | ||||
1130 | |||||
1131 | /// See AbstractAttribute::initialize(...). | ||||
1132 | void initialize(Attributor &A) override { AAPointerInfoImpl::initialize(A); } | ||||
1133 | |||||
1134 | /// Deal with an access and signal if it was handled successfully. | ||||
1135 | bool handleAccess(Attributor &A, Instruction &I, Value &Ptr, | ||||
1136 | Optional<Value *> Content, AccessKind Kind, int64_t Offset, | ||||
1137 | ChangeStatus &Changed, Type *Ty, | ||||
1138 | int64_t Size = AA::PointerInfo::OffsetAndSize::Unknown) { | ||||
1139 | using namespace AA::PointerInfo; | ||||
1140 | // No need to find a size if one is given or the offset is unknown. | ||||
1141 | if (Offset != OffsetAndSize::Unknown && Size == OffsetAndSize::Unknown && | ||||
1142 | Ty) { | ||||
1143 | const DataLayout &DL = A.getDataLayout(); | ||||
1144 | TypeSize AccessSize = DL.getTypeStoreSize(Ty); | ||||
1145 | if (!AccessSize.isScalable()) | ||||
1146 | Size = AccessSize.getFixedSize(); | ||||
1147 | } | ||||
1148 | Changed = Changed | addAccess(Offset, Size, I, Content, Kind, Ty); | ||||
1149 | return true; | ||||
1150 | }; | ||||
1151 | |||||
1152 | /// Helper struct, will support ranges eventually. | ||||
1153 | struct OffsetInfo { | ||||
1154 | int64_t Offset = AA::PointerInfo::OffsetAndSize::Unknown; | ||||
1155 | |||||
1156 | bool operator==(const OffsetInfo &OI) const { return Offset == OI.Offset; } | ||||
1157 | }; | ||||
1158 | |||||
1159 | /// See AbstractAttribute::updateImpl(...). | ||||
1160 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1161 | using namespace AA::PointerInfo; | ||||
1162 | State S = getState(); | ||||
1163 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
1164 | Value &AssociatedValue = getAssociatedValue(); | ||||
1165 | |||||
1166 | const DataLayout &DL = A.getDataLayout(); | ||||
1167 | DenseMap<Value *, OffsetInfo> OffsetInfoMap; | ||||
1168 | OffsetInfoMap[&AssociatedValue] = OffsetInfo{0}; | ||||
1169 | |||||
1170 | auto HandlePassthroughUser = [&](Value *Usr, OffsetInfo &PtrOI, | ||||
1171 | bool &Follow) { | ||||
1172 | OffsetInfo &UsrOI = OffsetInfoMap[Usr]; | ||||
1173 | UsrOI = PtrOI; | ||||
1174 | Follow = true; | ||||
1175 | return true; | ||||
1176 | }; | ||||
1177 | |||||
1178 | auto UsePred = [&](const Use &U, bool &Follow) -> bool { | ||||
1179 | Value *CurPtr = U.get(); | ||||
1180 | User *Usr = U.getUser(); | ||||
1181 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Analyze " << *CurPtr << " in "do { } while (false) | ||||
1182 | << *Usr << "\n")do { } while (false); | ||||
1183 | |||||
1184 | OffsetInfo &PtrOI = OffsetInfoMap[CurPtr]; | ||||
1185 | |||||
1186 | if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Usr)) { | ||||
1187 | if (CE->isCast()) | ||||
1188 | return HandlePassthroughUser(Usr, PtrOI, Follow); | ||||
1189 | if (CE->isCompare()) | ||||
1190 | return true; | ||||
1191 | if (!CE->isGEPWithNoNotionalOverIndexing()) { | ||||
1192 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Unhandled constant user " << *CEdo { } while (false) | ||||
1193 | << "\n")do { } while (false); | ||||
1194 | return false; | ||||
1195 | } | ||||
1196 | } | ||||
1197 | if (auto *GEP = dyn_cast<GEPOperator>(Usr)) { | ||||
1198 | OffsetInfo &UsrOI = OffsetInfoMap[Usr]; | ||||
1199 | UsrOI = PtrOI; | ||||
1200 | |||||
1201 | // TODO: Use range information. | ||||
1202 | if (PtrOI.Offset == OffsetAndSize::Unknown || | ||||
1203 | !GEP->hasAllConstantIndices()) { | ||||
1204 | UsrOI.Offset = OffsetAndSize::Unknown; | ||||
1205 | Follow = true; | ||||
1206 | return true; | ||||
1207 | } | ||||
1208 | |||||
1209 | SmallVector<Value *, 8> Indices; | ||||
1210 | for (Use &Idx : llvm::make_range(GEP->idx_begin(), GEP->idx_end())) { | ||||
1211 | if (auto *CIdx = dyn_cast<ConstantInt>(Idx)) { | ||||
1212 | Indices.push_back(CIdx); | ||||
1213 | continue; | ||||
1214 | } | ||||
1215 | |||||
1216 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Non constant GEP index " << *GEPdo { } while (false) | ||||
1217 | << " : " << *Idx << "\n")do { } while (false); | ||||
1218 | return false; | ||||
1219 | } | ||||
1220 | UsrOI.Offset = PtrOI.Offset + | ||||
1221 | DL.getIndexedOffsetInType( | ||||
1222 | CurPtr->getType()->getPointerElementType(), Indices); | ||||
1223 | Follow = true; | ||||
1224 | return true; | ||||
1225 | } | ||||
1226 | if (isa<CastInst>(Usr) || isa<SelectInst>(Usr)) | ||||
1227 | return HandlePassthroughUser(Usr, PtrOI, Follow); | ||||
1228 | |||||
1229 | // For PHIs we need to take care of the recurrence explicitly as the value | ||||
1230 | // might change while we iterate through a loop. For now, we give up if | ||||
1231 | // the PHI is not invariant. | ||||
1232 | if (isa<PHINode>(Usr)) { | ||||
1233 | // Check if the PHI is invariant (so far). | ||||
1234 | OffsetInfo &UsrOI = OffsetInfoMap[Usr]; | ||||
1235 | if (UsrOI == PtrOI) | ||||
1236 | return true; | ||||
1237 | |||||
1238 | // Check if the PHI operand has already an unknown offset as we can't | ||||
1239 | // improve on that anymore. | ||||
1240 | if (PtrOI.Offset == OffsetAndSize::Unknown) { | ||||
1241 | UsrOI = PtrOI; | ||||
1242 | Follow = true; | ||||
1243 | return true; | ||||
1244 | } | ||||
1245 | |||||
1246 | // Check if the PHI operand is not dependent on the PHI itself. | ||||
1247 | APInt Offset(DL.getIndexTypeSizeInBits(AssociatedValue.getType()), 0); | ||||
1248 | if (&AssociatedValue == CurPtr->stripAndAccumulateConstantOffsets( | ||||
1249 | DL, Offset, /* AllowNonInbounds */ true)) { | ||||
1250 | if (Offset != PtrOI.Offset) { | ||||
1251 | LLVM_DEBUG(dbgs()do { } while (false) | ||||
1252 | << "[AAPointerInfo] PHI operand pointer offset mismatch "do { } while (false) | ||||
1253 | << *CurPtr << " in " << *Usr << "\n")do { } while (false); | ||||
1254 | return false; | ||||
1255 | } | ||||
1256 | return HandlePassthroughUser(Usr, PtrOI, Follow); | ||||
1257 | } | ||||
1258 | |||||
1259 | // TODO: Approximate in case we know the direction of the recurrence. | ||||
1260 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] PHI operand is too complex "do { } while (false) | ||||
1261 | << *CurPtr << " in " << *Usr << "\n")do { } while (false); | ||||
1262 | UsrOI = PtrOI; | ||||
1263 | UsrOI.Offset = OffsetAndSize::Unknown; | ||||
1264 | Follow = true; | ||||
1265 | return true; | ||||
1266 | } | ||||
1267 | |||||
1268 | if (auto *LoadI = dyn_cast<LoadInst>(Usr)) | ||||
1269 | return handleAccess(A, *LoadI, *CurPtr, /* Content */ nullptr, | ||||
1270 | AccessKind::AK_READ, PtrOI.Offset, Changed, | ||||
1271 | LoadI->getType()); | ||||
1272 | if (auto *StoreI = dyn_cast<StoreInst>(Usr)) { | ||||
1273 | if (StoreI->getValueOperand() == CurPtr) { | ||||
1274 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Escaping use in store "do { } while (false) | ||||
1275 | << *StoreI << "\n")do { } while (false); | ||||
1276 | return false; | ||||
1277 | } | ||||
1278 | bool UsedAssumedInformation = false; | ||||
1279 | Optional<Value *> Content = A.getAssumedSimplified( | ||||
1280 | *StoreI->getValueOperand(), *this, UsedAssumedInformation); | ||||
1281 | return handleAccess(A, *StoreI, *CurPtr, Content, AccessKind::AK_WRITE, | ||||
1282 | PtrOI.Offset, Changed, | ||||
1283 | StoreI->getValueOperand()->getType()); | ||||
1284 | } | ||||
1285 | if (auto *CB = dyn_cast<CallBase>(Usr)) { | ||||
1286 | if (CB->isLifetimeStartOrEnd()) | ||||
1287 | return true; | ||||
1288 | if (CB->isArgOperand(&U)) { | ||||
1289 | unsigned ArgNo = CB->getArgOperandNo(&U); | ||||
1290 | const auto &CSArgPI = A.getAAFor<AAPointerInfo>( | ||||
1291 | *this, IRPosition::callsite_argument(*CB, ArgNo), | ||||
1292 | DepClassTy::REQUIRED); | ||||
1293 | Changed = translateAndAddCalleeState(A, CSArgPI, PtrOI.Offset, *CB) | | ||||
1294 | Changed; | ||||
1295 | return true; | ||||
1296 | } | ||||
1297 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Call user not handled " << *CBdo { } while (false) | ||||
1298 | << "\n")do { } while (false); | ||||
1299 | // TODO: Allow some call uses | ||||
1300 | return false; | ||||
1301 | } | ||||
1302 | |||||
1303 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] User not handled " << *Usr << "\n")do { } while (false); | ||||
1304 | return false; | ||||
1305 | }; | ||||
1306 | if (!A.checkForAllUses(UsePred, *this, AssociatedValue, | ||||
1307 | /* CheckBBLivenessOnly */ true)) | ||||
1308 | return indicatePessimisticFixpoint(); | ||||
1309 | |||||
1310 | LLVM_DEBUG({do { } while (false) | ||||
1311 | dbgs() << "Accesses by bin after update:\n";do { } while (false) | ||||
1312 | for (auto &It : AccessBins) {do { } while (false) | ||||
1313 | dbgs() << "[" << It.first.getOffset() << "-"do { } while (false) | ||||
1314 | << It.first.getOffset() + It.first.getSize()do { } while (false) | ||||
1315 | << "] : " << It.getSecond().size() << "\n";do { } while (false) | ||||
1316 | for (auto &Acc : It.getSecond()) {do { } while (false) | ||||
1317 | dbgs() << " - " << Acc.getKind() << " - " << *Acc.getLocalInst()do { } while (false) | ||||
1318 | << "\n";do { } while (false) | ||||
1319 | if (Acc.getLocalInst() != Acc.getRemoteInst())do { } while (false) | ||||
1320 | dbgs() << " --> "do { } while (false) | ||||
1321 | << *Acc.getRemoteInst() << "\n";do { } while (false) | ||||
1322 | if (!Acc.isWrittenValueYetUndetermined())do { } while (false) | ||||
1323 | dbgs() << " - " << Acc.getWrittenValue() << "\n";do { } while (false) | ||||
1324 | }do { } while (false) | ||||
1325 | }do { } while (false) | ||||
1326 | })do { } while (false); | ||||
1327 | |||||
1328 | return Changed; | ||||
1329 | } | ||||
1330 | |||||
1331 | /// See AbstractAttribute::trackStatistics() | ||||
1332 | void trackStatistics() const override { | ||||
1333 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||
1334 | } | ||||
1335 | }; | ||||
1336 | |||||
1337 | struct AAPointerInfoReturned final : AAPointerInfoImpl { | ||||
1338 | AAPointerInfoReturned(const IRPosition &IRP, Attributor &A) | ||||
1339 | : AAPointerInfoImpl(IRP, A) {} | ||||
1340 | |||||
1341 | /// See AbstractAttribute::updateImpl(...). | ||||
1342 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1343 | return indicatePessimisticFixpoint(); | ||||
1344 | } | ||||
1345 | |||||
1346 | /// See AbstractAttribute::trackStatistics() | ||||
1347 | void trackStatistics() const override { | ||||
1348 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||
1349 | } | ||||
1350 | }; | ||||
1351 | |||||
1352 | struct AAPointerInfoArgument final : AAPointerInfoFloating { | ||||
1353 | AAPointerInfoArgument(const IRPosition &IRP, Attributor &A) | ||||
1354 | : AAPointerInfoFloating(IRP, A) {} | ||||
1355 | |||||
1356 | /// See AbstractAttribute::initialize(...). | ||||
1357 | void initialize(Attributor &A) override { | ||||
1358 | AAPointerInfoFloating::initialize(A); | ||||
1359 | if (getAnchorScope()->isDeclaration()) | ||||
1360 | indicatePessimisticFixpoint(); | ||||
1361 | } | ||||
1362 | |||||
1363 | /// See AbstractAttribute::trackStatistics() | ||||
1364 | void trackStatistics() const override { | ||||
1365 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||
1366 | } | ||||
1367 | }; | ||||
1368 | |||||
1369 | struct AAPointerInfoCallSiteArgument final : AAPointerInfoFloating { | ||||
1370 | AAPointerInfoCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
1371 | : AAPointerInfoFloating(IRP, A) {} | ||||
1372 | |||||
1373 | /// See AbstractAttribute::updateImpl(...). | ||||
1374 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1375 | using namespace AA::PointerInfo; | ||||
1376 | // We handle memory intrinsics explicitly, at least the first (= | ||||
1377 | // destination) and second (=source) arguments as we know how they are | ||||
1378 | // accessed. | ||||
1379 | if (auto *MI = dyn_cast_or_null<MemIntrinsic>(getCtxI())) { | ||||
1380 | ConstantInt *Length = dyn_cast<ConstantInt>(MI->getLength()); | ||||
1381 | int64_t LengthVal = OffsetAndSize::Unknown; | ||||
1382 | if (Length) | ||||
1383 | LengthVal = Length->getSExtValue(); | ||||
1384 | Value &Ptr = getAssociatedValue(); | ||||
1385 | unsigned ArgNo = getIRPosition().getCallSiteArgNo(); | ||||
1386 | ChangeStatus Changed; | ||||
1387 | if (ArgNo == 0) { | ||||
1388 | handleAccess(A, *MI, Ptr, nullptr, AccessKind::AK_WRITE, 0, Changed, | ||||
1389 | nullptr, LengthVal); | ||||
1390 | } else if (ArgNo == 1) { | ||||
1391 | handleAccess(A, *MI, Ptr, nullptr, AccessKind::AK_READ, 0, Changed, | ||||
1392 | nullptr, LengthVal); | ||||
1393 | } else { | ||||
1394 | LLVM_DEBUG(dbgs() << "[AAPointerInfo] Unhandled memory intrinsic "do { } while (false) | ||||
1395 | << *MI << "\n")do { } while (false); | ||||
1396 | return indicatePessimisticFixpoint(); | ||||
1397 | } | ||||
1398 | return Changed; | ||||
1399 | } | ||||
1400 | |||||
1401 | // TODO: Once we have call site specific value information we can provide | ||||
1402 | // call site specific liveness information and then it makes | ||||
1403 | // sense to specialize attributes for call sites arguments instead of | ||||
1404 | // redirecting requests to the callee argument. | ||||
1405 | Argument *Arg = getAssociatedArgument(); | ||||
1406 | if (!Arg) | ||||
1407 | return indicatePessimisticFixpoint(); | ||||
1408 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||
1409 | auto &ArgAA = | ||||
1410 | A.getAAFor<AAPointerInfo>(*this, ArgPos, DepClassTy::REQUIRED); | ||||
1411 | return translateAndAddCalleeState(A, ArgAA, 0, *cast<CallBase>(getCtxI())); | ||||
1412 | } | ||||
1413 | |||||
1414 | /// See AbstractAttribute::trackStatistics() | ||||
1415 | void trackStatistics() const override { | ||||
1416 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||
1417 | } | ||||
1418 | }; | ||||
1419 | |||||
1420 | struct AAPointerInfoCallSiteReturned final : AAPointerInfoFloating { | ||||
1421 | AAPointerInfoCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
1422 | : AAPointerInfoFloating(IRP, A) {} | ||||
1423 | |||||
1424 | /// See AbstractAttribute::trackStatistics() | ||||
1425 | void trackStatistics() const override { | ||||
1426 | AAPointerInfoImpl::trackPointerInfoStatistics(getIRPosition()); | ||||
1427 | } | ||||
1428 | }; | ||||
1429 | |||||
1430 | /// -----------------------NoUnwind Function Attribute-------------------------- | ||||
1431 | |||||
1432 | struct AANoUnwindImpl : AANoUnwind { | ||||
1433 | AANoUnwindImpl(const IRPosition &IRP, Attributor &A) : AANoUnwind(IRP, A) {} | ||||
1434 | |||||
1435 | const std::string getAsStr() const override { | ||||
1436 | return getAssumed() ? "nounwind" : "may-unwind"; | ||||
1437 | } | ||||
1438 | |||||
1439 | /// See AbstractAttribute::updateImpl(...). | ||||
1440 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1441 | auto Opcodes = { | ||||
1442 | (unsigned)Instruction::Invoke, (unsigned)Instruction::CallBr, | ||||
1443 | (unsigned)Instruction::Call, (unsigned)Instruction::CleanupRet, | ||||
1444 | (unsigned)Instruction::CatchSwitch, (unsigned)Instruction::Resume}; | ||||
1445 | |||||
1446 | auto CheckForNoUnwind = [&](Instruction &I) { | ||||
1447 | if (!I.mayThrow()) | ||||
1448 | return true; | ||||
1449 | |||||
1450 | if (const auto *CB = dyn_cast<CallBase>(&I)) { | ||||
1451 | const auto &NoUnwindAA = A.getAAFor<AANoUnwind>( | ||||
1452 | *this, IRPosition::callsite_function(*CB), DepClassTy::REQUIRED); | ||||
1453 | return NoUnwindAA.isAssumedNoUnwind(); | ||||
1454 | } | ||||
1455 | return false; | ||||
1456 | }; | ||||
1457 | |||||
1458 | bool UsedAssumedInformation = false; | ||||
1459 | if (!A.checkForAllInstructions(CheckForNoUnwind, *this, Opcodes, | ||||
1460 | UsedAssumedInformation)) | ||||
1461 | return indicatePessimisticFixpoint(); | ||||
1462 | |||||
1463 | return ChangeStatus::UNCHANGED; | ||||
1464 | } | ||||
1465 | }; | ||||
1466 | |||||
1467 | struct AANoUnwindFunction final : public AANoUnwindImpl { | ||||
1468 | AANoUnwindFunction(const IRPosition &IRP, Attributor &A) | ||||
1469 | : AANoUnwindImpl(IRP, A) {} | ||||
1470 | |||||
1471 | /// See AbstractAttribute::trackStatistics() | ||||
1472 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(nounwind){ static llvm::Statistic NumIRFunction_nounwind = {"attributor" , "NumIRFunction_nounwind", ("Number of " "functions" " marked '" "nounwind" "'")};; ++(NumIRFunction_nounwind); } } | ||||
1473 | }; | ||||
1474 | |||||
1475 | /// NoUnwind attribute deduction for a call sites. | ||||
1476 | struct AANoUnwindCallSite final : AANoUnwindImpl { | ||||
1477 | AANoUnwindCallSite(const IRPosition &IRP, Attributor &A) | ||||
1478 | : AANoUnwindImpl(IRP, A) {} | ||||
1479 | |||||
1480 | /// See AbstractAttribute::initialize(...). | ||||
1481 | void initialize(Attributor &A) override { | ||||
1482 | AANoUnwindImpl::initialize(A); | ||||
1483 | Function *F = getAssociatedFunction(); | ||||
1484 | if (!F || F->isDeclaration()) | ||||
1485 | indicatePessimisticFixpoint(); | ||||
1486 | } | ||||
1487 | |||||
1488 | /// See AbstractAttribute::updateImpl(...). | ||||
1489 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1490 | // TODO: Once we have call site specific value information we can provide | ||||
1491 | // call site specific liveness information and then it makes | ||||
1492 | // sense to specialize attributes for call sites arguments instead of | ||||
1493 | // redirecting requests to the callee argument. | ||||
1494 | Function *F = getAssociatedFunction(); | ||||
1495 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
1496 | auto &FnAA = A.getAAFor<AANoUnwind>(*this, FnPos, DepClassTy::REQUIRED); | ||||
1497 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||
1498 | } | ||||
1499 | |||||
1500 | /// See AbstractAttribute::trackStatistics() | ||||
1501 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(nounwind){ static llvm::Statistic NumIRCS_nounwind = {"attributor", "NumIRCS_nounwind" , ("Number of " "call site" " marked '" "nounwind" "'")};; ++ (NumIRCS_nounwind); }; } | ||||
1502 | }; | ||||
1503 | |||||
1504 | /// --------------------- Function Return Values ------------------------------- | ||||
1505 | |||||
1506 | /// "Attribute" that collects all potential returned values and the return | ||||
1507 | /// instructions that they arise from. | ||||
1508 | /// | ||||
1509 | /// If there is a unique returned value R, the manifest method will: | ||||
1510 | /// - mark R with the "returned" attribute, if R is an argument. | ||||
1511 | class AAReturnedValuesImpl : public AAReturnedValues, public AbstractState { | ||||
1512 | |||||
1513 | /// Mapping of values potentially returned by the associated function to the | ||||
1514 | /// return instructions that might return them. | ||||
1515 | MapVector<Value *, SmallSetVector<ReturnInst *, 4>> ReturnedValues; | ||||
1516 | |||||
1517 | /// State flags | ||||
1518 | /// | ||||
1519 | ///{ | ||||
1520 | bool IsFixed = false; | ||||
1521 | bool IsValidState = true; | ||||
1522 | ///} | ||||
1523 | |||||
1524 | public: | ||||
1525 | AAReturnedValuesImpl(const IRPosition &IRP, Attributor &A) | ||||
1526 | : AAReturnedValues(IRP, A) {} | ||||
1527 | |||||
1528 | /// See AbstractAttribute::initialize(...). | ||||
1529 | void initialize(Attributor &A) override { | ||||
1530 | // Reset the state. | ||||
1531 | IsFixed = false; | ||||
1532 | IsValidState = true; | ||||
1533 | ReturnedValues.clear(); | ||||
1534 | |||||
1535 | Function *F = getAssociatedFunction(); | ||||
1536 | if (!F || F->isDeclaration()) { | ||||
1537 | indicatePessimisticFixpoint(); | ||||
1538 | return; | ||||
1539 | } | ||||
1540 | assert(!F->getReturnType()->isVoidTy() &&(static_cast<void> (0)) | ||||
1541 | "Did not expect a void return type!")(static_cast<void> (0)); | ||||
1542 | |||||
1543 | // The map from instruction opcodes to those instructions in the function. | ||||
1544 | auto &OpcodeInstMap = A.getInfoCache().getOpcodeInstMapForFunction(*F); | ||||
1545 | |||||
1546 | // Look through all arguments, if one is marked as returned we are done. | ||||
1547 | for (Argument &Arg : F->args()) { | ||||
1548 | if (Arg.hasReturnedAttr()) { | ||||
1549 | auto &ReturnInstSet = ReturnedValues[&Arg]; | ||||
1550 | if (auto *Insts = OpcodeInstMap.lookup(Instruction::Ret)) | ||||
1551 | for (Instruction *RI : *Insts) | ||||
1552 | ReturnInstSet.insert(cast<ReturnInst>(RI)); | ||||
1553 | |||||
1554 | indicateOptimisticFixpoint(); | ||||
1555 | return; | ||||
1556 | } | ||||
1557 | } | ||||
1558 | |||||
1559 | if (!A.isFunctionIPOAmendable(*F)) | ||||
1560 | indicatePessimisticFixpoint(); | ||||
1561 | } | ||||
1562 | |||||
1563 | /// See AbstractAttribute::manifest(...). | ||||
1564 | ChangeStatus manifest(Attributor &A) override; | ||||
1565 | |||||
1566 | /// See AbstractAttribute::getState(...). | ||||
1567 | AbstractState &getState() override { return *this; } | ||||
1568 | |||||
1569 | /// See AbstractAttribute::getState(...). | ||||
1570 | const AbstractState &getState() const override { return *this; } | ||||
1571 | |||||
1572 | /// See AbstractAttribute::updateImpl(Attributor &A). | ||||
1573 | ChangeStatus updateImpl(Attributor &A) override; | ||||
1574 | |||||
1575 | llvm::iterator_range<iterator> returned_values() override { | ||||
1576 | return llvm::make_range(ReturnedValues.begin(), ReturnedValues.end()); | ||||
1577 | } | ||||
1578 | |||||
1579 | llvm::iterator_range<const_iterator> returned_values() const override { | ||||
1580 | return llvm::make_range(ReturnedValues.begin(), ReturnedValues.end()); | ||||
1581 | } | ||||
1582 | |||||
1583 | /// Return the number of potential return values, -1 if unknown. | ||||
1584 | size_t getNumReturnValues() const override { | ||||
1585 | return isValidState() ? ReturnedValues.size() : -1; | ||||
1586 | } | ||||
1587 | |||||
1588 | /// Return an assumed unique return value if a single candidate is found. If | ||||
1589 | /// there cannot be one, return a nullptr. If it is not clear yet, return the | ||||
1590 | /// Optional::NoneType. | ||||
1591 | Optional<Value *> getAssumedUniqueReturnValue(Attributor &A) const; | ||||
1592 | |||||
1593 | /// See AbstractState::checkForAllReturnedValues(...). | ||||
1594 | bool checkForAllReturnedValuesAndReturnInsts( | ||||
1595 | function_ref<bool(Value &, const SmallSetVector<ReturnInst *, 4> &)> Pred) | ||||
1596 | const override; | ||||
1597 | |||||
1598 | /// Pretty print the attribute similar to the IR representation. | ||||
1599 | const std::string getAsStr() const override; | ||||
1600 | |||||
1601 | /// See AbstractState::isAtFixpoint(). | ||||
1602 | bool isAtFixpoint() const override { return IsFixed; } | ||||
1603 | |||||
1604 | /// See AbstractState::isValidState(). | ||||
1605 | bool isValidState() const override { return IsValidState; } | ||||
1606 | |||||
1607 | /// See AbstractState::indicateOptimisticFixpoint(...). | ||||
1608 | ChangeStatus indicateOptimisticFixpoint() override { | ||||
1609 | IsFixed = true; | ||||
1610 | return ChangeStatus::UNCHANGED; | ||||
1611 | } | ||||
1612 | |||||
1613 | ChangeStatus indicatePessimisticFixpoint() override { | ||||
1614 | IsFixed = true; | ||||
1615 | IsValidState = false; | ||||
1616 | return ChangeStatus::CHANGED; | ||||
1617 | } | ||||
1618 | }; | ||||
1619 | |||||
1620 | ChangeStatus AAReturnedValuesImpl::manifest(Attributor &A) { | ||||
1621 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
1622 | |||||
1623 | // Bookkeeping. | ||||
1624 | assert(isValidState())(static_cast<void> (0)); | ||||
1625 | STATS_DECLTRACK(KnownReturnValues, FunctionReturn,{ static llvm::Statistic NumIRFunctionReturn_KnownReturnValues = {"attributor", "NumIRFunctionReturn_KnownReturnValues", "Number of function with known return values" };; ++(NumIRFunctionReturn_KnownReturnValues); } | ||||
1626 | "Number of function with known return values"){ static llvm::Statistic NumIRFunctionReturn_KnownReturnValues = {"attributor", "NumIRFunctionReturn_KnownReturnValues", "Number of function with known return values" };; ++(NumIRFunctionReturn_KnownReturnValues); }; | ||||
1627 | |||||
1628 | // Check if we have an assumed unique return value that we could manifest. | ||||
1629 | Optional<Value *> UniqueRV = getAssumedUniqueReturnValue(A); | ||||
1630 | |||||
1631 | if (!UniqueRV.hasValue() || !UniqueRV.getValue()) | ||||
1632 | return Changed; | ||||
1633 | |||||
1634 | // Bookkeeping. | ||||
1635 | STATS_DECLTRACK(UniqueReturnValue, FunctionReturn,{ static llvm::Statistic NumIRFunctionReturn_UniqueReturnValue = {"attributor", "NumIRFunctionReturn_UniqueReturnValue", "Number of function with unique return" };; ++(NumIRFunctionReturn_UniqueReturnValue); } | ||||
1636 | "Number of function with unique return"){ static llvm::Statistic NumIRFunctionReturn_UniqueReturnValue = {"attributor", "NumIRFunctionReturn_UniqueReturnValue", "Number of function with unique return" };; ++(NumIRFunctionReturn_UniqueReturnValue); }; | ||||
1637 | // If the assumed unique return value is an argument, annotate it. | ||||
1638 | if (auto *UniqueRVArg = dyn_cast<Argument>(UniqueRV.getValue())) { | ||||
1639 | if (UniqueRVArg->getType()->canLosslesslyBitCastTo( | ||||
1640 | getAssociatedFunction()->getReturnType())) { | ||||
1641 | getIRPosition() = IRPosition::argument(*UniqueRVArg); | ||||
1642 | Changed = IRAttribute::manifest(A); | ||||
1643 | } | ||||
1644 | } | ||||
1645 | return Changed; | ||||
1646 | } | ||||
1647 | |||||
1648 | const std::string AAReturnedValuesImpl::getAsStr() const { | ||||
1649 | return (isAtFixpoint() ? "returns(#" : "may-return(#") + | ||||
1650 | (isValidState() ? std::to_string(getNumReturnValues()) : "?") + ")"; | ||||
1651 | } | ||||
1652 | |||||
1653 | Optional<Value *> | ||||
1654 | AAReturnedValuesImpl::getAssumedUniqueReturnValue(Attributor &A) const { | ||||
1655 | // If checkForAllReturnedValues provides a unique value, ignoring potential | ||||
1656 | // undef values that can also be present, it is assumed to be the actual | ||||
1657 | // return value and forwarded to the caller of this method. If there are | ||||
1658 | // multiple, a nullptr is returned indicating there cannot be a unique | ||||
1659 | // returned value. | ||||
1660 | Optional<Value *> UniqueRV; | ||||
1661 | Type *Ty = getAssociatedFunction()->getReturnType(); | ||||
1662 | |||||
1663 | auto Pred = [&](Value &RV) -> bool { | ||||
1664 | UniqueRV = AA::combineOptionalValuesInAAValueLatice(UniqueRV, &RV, Ty); | ||||
1665 | return UniqueRV != Optional<Value *>(nullptr); | ||||
1666 | }; | ||||
1667 | |||||
1668 | if (!A.checkForAllReturnedValues(Pred, *this)) | ||||
1669 | UniqueRV = nullptr; | ||||
1670 | |||||
1671 | return UniqueRV; | ||||
1672 | } | ||||
1673 | |||||
1674 | bool AAReturnedValuesImpl::checkForAllReturnedValuesAndReturnInsts( | ||||
1675 | function_ref<bool(Value &, const SmallSetVector<ReturnInst *, 4> &)> Pred) | ||||
1676 | const { | ||||
1677 | if (!isValidState()) | ||||
1678 | return false; | ||||
1679 | |||||
1680 | // Check all returned values but ignore call sites as long as we have not | ||||
1681 | // encountered an overdefined one during an update. | ||||
1682 | for (auto &It : ReturnedValues) { | ||||
1683 | Value *RV = It.first; | ||||
1684 | if (!Pred(*RV, It.second)) | ||||
1685 | return false; | ||||
1686 | } | ||||
1687 | |||||
1688 | return true; | ||||
1689 | } | ||||
1690 | |||||
1691 | ChangeStatus AAReturnedValuesImpl::updateImpl(Attributor &A) { | ||||
1692 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
1693 | |||||
1694 | auto ReturnValueCB = [&](Value &V, const Instruction *CtxI, ReturnInst &Ret, | ||||
1695 | bool) -> bool { | ||||
1696 | bool UsedAssumedInformation = false; | ||||
1697 | Optional<Value *> SimpleRetVal = | ||||
1698 | A.getAssumedSimplified(V, *this, UsedAssumedInformation); | ||||
1699 | if (!SimpleRetVal.hasValue()) | ||||
1700 | return true; | ||||
1701 | if (!SimpleRetVal.getValue()) | ||||
1702 | return false; | ||||
1703 | Value *RetVal = *SimpleRetVal; | ||||
1704 | assert(AA::isValidInScope(*RetVal, Ret.getFunction()) &&(static_cast<void> (0)) | ||||
1705 | "Assumed returned value should be valid in function scope!")(static_cast<void> (0)); | ||||
1706 | if (ReturnedValues[RetVal].insert(&Ret)) | ||||
1707 | Changed = ChangeStatus::CHANGED; | ||||
1708 | return true; | ||||
1709 | }; | ||||
1710 | |||||
1711 | auto ReturnInstCB = [&](Instruction &I) { | ||||
1712 | ReturnInst &Ret = cast<ReturnInst>(I); | ||||
1713 | return genericValueTraversal<ReturnInst>( | ||||
1714 | A, IRPosition::value(*Ret.getReturnValue()), *this, Ret, ReturnValueCB, | ||||
1715 | &I); | ||||
1716 | }; | ||||
1717 | |||||
1718 | // Discover returned values from all live returned instructions in the | ||||
1719 | // associated function. | ||||
1720 | bool UsedAssumedInformation = false; | ||||
1721 | if (!A.checkForAllInstructions(ReturnInstCB, *this, {Instruction::Ret}, | ||||
1722 | UsedAssumedInformation)) | ||||
1723 | return indicatePessimisticFixpoint(); | ||||
1724 | return Changed; | ||||
1725 | } | ||||
1726 | |||||
1727 | struct AAReturnedValuesFunction final : public AAReturnedValuesImpl { | ||||
1728 | AAReturnedValuesFunction(const IRPosition &IRP, Attributor &A) | ||||
1729 | : AAReturnedValuesImpl(IRP, A) {} | ||||
1730 | |||||
1731 | /// See AbstractAttribute::trackStatistics() | ||||
1732 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(returned){ static llvm::Statistic NumIRArguments_returned = {"attributor" , "NumIRArguments_returned", ("Number of " "arguments" " marked '" "returned" "'")};; ++(NumIRArguments_returned); } } | ||||
1733 | }; | ||||
1734 | |||||
1735 | /// Returned values information for a call sites. | ||||
1736 | struct AAReturnedValuesCallSite final : AAReturnedValuesImpl { | ||||
1737 | AAReturnedValuesCallSite(const IRPosition &IRP, Attributor &A) | ||||
1738 | : AAReturnedValuesImpl(IRP, A) {} | ||||
1739 | |||||
1740 | /// See AbstractAttribute::initialize(...). | ||||
1741 | void initialize(Attributor &A) override { | ||||
1742 | // TODO: Once we have call site specific value information we can provide | ||||
1743 | // call site specific liveness information and then it makes | ||||
1744 | // sense to specialize attributes for call sites instead of | ||||
1745 | // redirecting requests to the callee. | ||||
1746 | llvm_unreachable("Abstract attributes for returned values are not "__builtin_unreachable() | ||||
1747 | "supported for call sites yet!")__builtin_unreachable(); | ||||
1748 | } | ||||
1749 | |||||
1750 | /// See AbstractAttribute::updateImpl(...). | ||||
1751 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1752 | return indicatePessimisticFixpoint(); | ||||
1753 | } | ||||
1754 | |||||
1755 | /// See AbstractAttribute::trackStatistics() | ||||
1756 | void trackStatistics() const override {} | ||||
1757 | }; | ||||
1758 | |||||
1759 | /// ------------------------ NoSync Function Attribute ------------------------- | ||||
1760 | |||||
1761 | struct AANoSyncImpl : AANoSync { | ||||
1762 | AANoSyncImpl(const IRPosition &IRP, Attributor &A) : AANoSync(IRP, A) {} | ||||
1763 | |||||
1764 | const std::string getAsStr() const override { | ||||
1765 | return getAssumed() ? "nosync" : "may-sync"; | ||||
1766 | } | ||||
1767 | |||||
1768 | /// See AbstractAttribute::updateImpl(...). | ||||
1769 | ChangeStatus updateImpl(Attributor &A) override; | ||||
1770 | |||||
1771 | /// Helper function used to determine whether an instruction is non-relaxed | ||||
1772 | /// atomic. In other words, if an atomic instruction does not have unordered | ||||
1773 | /// or monotonic ordering | ||||
1774 | static bool isNonRelaxedAtomic(Instruction *I); | ||||
1775 | |||||
1776 | /// Helper function specific for intrinsics which are potentially volatile | ||||
1777 | static bool isNoSyncIntrinsic(Instruction *I); | ||||
1778 | }; | ||||
1779 | |||||
1780 | bool AANoSyncImpl::isNonRelaxedAtomic(Instruction *I) { | ||||
1781 | if (!I->isAtomic()) | ||||
1782 | return false; | ||||
1783 | |||||
1784 | if (auto *FI = dyn_cast<FenceInst>(I)) | ||||
1785 | // All legal orderings for fence are stronger than monotonic. | ||||
1786 | return FI->getSyncScopeID() != SyncScope::SingleThread; | ||||
1787 | else if (auto *AI = dyn_cast<AtomicCmpXchgInst>(I)) { | ||||
1788 | // Unordered is not a legal ordering for cmpxchg. | ||||
1789 | return (AI->getSuccessOrdering() != AtomicOrdering::Monotonic || | ||||
1790 | AI->getFailureOrdering() != AtomicOrdering::Monotonic); | ||||
1791 | } | ||||
1792 | |||||
1793 | AtomicOrdering Ordering; | ||||
1794 | switch (I->getOpcode()) { | ||||
1795 | case Instruction::AtomicRMW: | ||||
1796 | Ordering = cast<AtomicRMWInst>(I)->getOrdering(); | ||||
1797 | break; | ||||
1798 | case Instruction::Store: | ||||
1799 | Ordering = cast<StoreInst>(I)->getOrdering(); | ||||
1800 | break; | ||||
1801 | case Instruction::Load: | ||||
1802 | Ordering = cast<LoadInst>(I)->getOrdering(); | ||||
1803 | break; | ||||
1804 | default: | ||||
1805 | llvm_unreachable(__builtin_unreachable() | ||||
1806 | "New atomic operations need to be known in the attributor.")__builtin_unreachable(); | ||||
1807 | } | ||||
1808 | |||||
1809 | return (Ordering != AtomicOrdering::Unordered && | ||||
1810 | Ordering != AtomicOrdering::Monotonic); | ||||
1811 | } | ||||
1812 | |||||
1813 | /// Return true if this intrinsic is nosync. This is only used for intrinsics | ||||
1814 | /// which would be nosync except that they have a volatile flag. All other | ||||
1815 | /// intrinsics are simply annotated with the nosync attribute in Intrinsics.td. | ||||
1816 | bool AANoSyncImpl::isNoSyncIntrinsic(Instruction *I) { | ||||
1817 | if (auto *MI = dyn_cast<MemIntrinsic>(I)) | ||||
1818 | return !MI->isVolatile(); | ||||
1819 | return false; | ||||
1820 | } | ||||
1821 | |||||
1822 | ChangeStatus AANoSyncImpl::updateImpl(Attributor &A) { | ||||
1823 | |||||
1824 | auto CheckRWInstForNoSync = [&](Instruction &I) { | ||||
1825 | /// We are looking for volatile instructions or Non-Relaxed atomics. | ||||
1826 | |||||
1827 | if (const auto *CB = dyn_cast<CallBase>(&I)) { | ||||
1828 | if (CB->hasFnAttr(Attribute::NoSync)) | ||||
1829 | return true; | ||||
1830 | |||||
1831 | if (isNoSyncIntrinsic(&I)) | ||||
1832 | return true; | ||||
1833 | |||||
1834 | const auto &NoSyncAA = A.getAAFor<AANoSync>( | ||||
1835 | *this, IRPosition::callsite_function(*CB), DepClassTy::REQUIRED); | ||||
1836 | return NoSyncAA.isAssumedNoSync(); | ||||
1837 | } | ||||
1838 | |||||
1839 | if (!I.isVolatile() && !isNonRelaxedAtomic(&I)) | ||||
1840 | return true; | ||||
1841 | |||||
1842 | return false; | ||||
1843 | }; | ||||
1844 | |||||
1845 | auto CheckForNoSync = [&](Instruction &I) { | ||||
1846 | // At this point we handled all read/write effects and they are all | ||||
1847 | // nosync, so they can be skipped. | ||||
1848 | if (I.mayReadOrWriteMemory()) | ||||
1849 | return true; | ||||
1850 | |||||
1851 | // non-convergent and readnone imply nosync. | ||||
1852 | return !cast<CallBase>(I).isConvergent(); | ||||
1853 | }; | ||||
1854 | |||||
1855 | bool UsedAssumedInformation = false; | ||||
1856 | if (!A.checkForAllReadWriteInstructions(CheckRWInstForNoSync, *this, | ||||
1857 | UsedAssumedInformation) || | ||||
1858 | !A.checkForAllCallLikeInstructions(CheckForNoSync, *this, | ||||
1859 | UsedAssumedInformation)) | ||||
1860 | return indicatePessimisticFixpoint(); | ||||
1861 | |||||
1862 | return ChangeStatus::UNCHANGED; | ||||
1863 | } | ||||
1864 | |||||
1865 | struct AANoSyncFunction final : public AANoSyncImpl { | ||||
1866 | AANoSyncFunction(const IRPosition &IRP, Attributor &A) | ||||
1867 | : AANoSyncImpl(IRP, A) {} | ||||
1868 | |||||
1869 | /// See AbstractAttribute::trackStatistics() | ||||
1870 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(nosync){ static llvm::Statistic NumIRFunction_nosync = {"attributor" , "NumIRFunction_nosync", ("Number of " "functions" " marked '" "nosync" "'")};; ++(NumIRFunction_nosync); } } | ||||
1871 | }; | ||||
1872 | |||||
1873 | /// NoSync attribute deduction for a call sites. | ||||
1874 | struct AANoSyncCallSite final : AANoSyncImpl { | ||||
1875 | AANoSyncCallSite(const IRPosition &IRP, Attributor &A) | ||||
1876 | : AANoSyncImpl(IRP, A) {} | ||||
1877 | |||||
1878 | /// See AbstractAttribute::initialize(...). | ||||
1879 | void initialize(Attributor &A) override { | ||||
1880 | AANoSyncImpl::initialize(A); | ||||
1881 | Function *F = getAssociatedFunction(); | ||||
1882 | if (!F || F->isDeclaration()) | ||||
1883 | indicatePessimisticFixpoint(); | ||||
1884 | } | ||||
1885 | |||||
1886 | /// See AbstractAttribute::updateImpl(...). | ||||
1887 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1888 | // TODO: Once we have call site specific value information we can provide | ||||
1889 | // call site specific liveness information and then it makes | ||||
1890 | // sense to specialize attributes for call sites arguments instead of | ||||
1891 | // redirecting requests to the callee argument. | ||||
1892 | Function *F = getAssociatedFunction(); | ||||
1893 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
1894 | auto &FnAA = A.getAAFor<AANoSync>(*this, FnPos, DepClassTy::REQUIRED); | ||||
1895 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||
1896 | } | ||||
1897 | |||||
1898 | /// See AbstractAttribute::trackStatistics() | ||||
1899 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(nosync){ static llvm::Statistic NumIRCS_nosync = {"attributor", "NumIRCS_nosync" , ("Number of " "call site" " marked '" "nosync" "'")};; ++(NumIRCS_nosync ); }; } | ||||
1900 | }; | ||||
1901 | |||||
1902 | /// ------------------------ No-Free Attributes ---------------------------- | ||||
1903 | |||||
1904 | struct AANoFreeImpl : public AANoFree { | ||||
1905 | AANoFreeImpl(const IRPosition &IRP, Attributor &A) : AANoFree(IRP, A) {} | ||||
1906 | |||||
1907 | /// See AbstractAttribute::updateImpl(...). | ||||
1908 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1909 | auto CheckForNoFree = [&](Instruction &I) { | ||||
1910 | const auto &CB = cast<CallBase>(I); | ||||
1911 | if (CB.hasFnAttr(Attribute::NoFree)) | ||||
1912 | return true; | ||||
1913 | |||||
1914 | const auto &NoFreeAA = A.getAAFor<AANoFree>( | ||||
1915 | *this, IRPosition::callsite_function(CB), DepClassTy::REQUIRED); | ||||
1916 | return NoFreeAA.isAssumedNoFree(); | ||||
1917 | }; | ||||
1918 | |||||
1919 | bool UsedAssumedInformation = false; | ||||
1920 | if (!A.checkForAllCallLikeInstructions(CheckForNoFree, *this, | ||||
1921 | UsedAssumedInformation)) | ||||
1922 | return indicatePessimisticFixpoint(); | ||||
1923 | return ChangeStatus::UNCHANGED; | ||||
1924 | } | ||||
1925 | |||||
1926 | /// See AbstractAttribute::getAsStr(). | ||||
1927 | const std::string getAsStr() const override { | ||||
1928 | return getAssumed() ? "nofree" : "may-free"; | ||||
1929 | } | ||||
1930 | }; | ||||
1931 | |||||
1932 | struct AANoFreeFunction final : public AANoFreeImpl { | ||||
1933 | AANoFreeFunction(const IRPosition &IRP, Attributor &A) | ||||
1934 | : AANoFreeImpl(IRP, A) {} | ||||
1935 | |||||
1936 | /// See AbstractAttribute::trackStatistics() | ||||
1937 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(nofree){ static llvm::Statistic NumIRFunction_nofree = {"attributor" , "NumIRFunction_nofree", ("Number of " "functions" " marked '" "nofree" "'")};; ++(NumIRFunction_nofree); } } | ||||
1938 | }; | ||||
1939 | |||||
1940 | /// NoFree attribute deduction for a call sites. | ||||
1941 | struct AANoFreeCallSite final : AANoFreeImpl { | ||||
1942 | AANoFreeCallSite(const IRPosition &IRP, Attributor &A) | ||||
1943 | : AANoFreeImpl(IRP, A) {} | ||||
1944 | |||||
1945 | /// See AbstractAttribute::initialize(...). | ||||
1946 | void initialize(Attributor &A) override { | ||||
1947 | AANoFreeImpl::initialize(A); | ||||
1948 | Function *F = getAssociatedFunction(); | ||||
1949 | if (!F || F->isDeclaration()) | ||||
1950 | indicatePessimisticFixpoint(); | ||||
1951 | } | ||||
1952 | |||||
1953 | /// See AbstractAttribute::updateImpl(...). | ||||
1954 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1955 | // TODO: Once we have call site specific value information we can provide | ||||
1956 | // call site specific liveness information and then it makes | ||||
1957 | // sense to specialize attributes for call sites arguments instead of | ||||
1958 | // redirecting requests to the callee argument. | ||||
1959 | Function *F = getAssociatedFunction(); | ||||
1960 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
1961 | auto &FnAA = A.getAAFor<AANoFree>(*this, FnPos, DepClassTy::REQUIRED); | ||||
1962 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||
1963 | } | ||||
1964 | |||||
1965 | /// See AbstractAttribute::trackStatistics() | ||||
1966 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(nofree){ static llvm::Statistic NumIRCS_nofree = {"attributor", "NumIRCS_nofree" , ("Number of " "call site" " marked '" "nofree" "'")};; ++(NumIRCS_nofree ); }; } | ||||
1967 | }; | ||||
1968 | |||||
1969 | /// NoFree attribute for floating values. | ||||
1970 | struct AANoFreeFloating : AANoFreeImpl { | ||||
1971 | AANoFreeFloating(const IRPosition &IRP, Attributor &A) | ||||
1972 | : AANoFreeImpl(IRP, A) {} | ||||
1973 | |||||
1974 | /// See AbstractAttribute::trackStatistics() | ||||
1975 | void trackStatistics() const override{STATS_DECLTRACK_FLOATING_ATTR(nofree){ static llvm::Statistic NumIRFloating_nofree = {"attributor" , "NumIRFloating_nofree", ("Number of floating values known to be '" "nofree" "'")};; ++(NumIRFloating_nofree); }} | ||||
1976 | |||||
1977 | /// See Abstract Attribute::updateImpl(...). | ||||
1978 | ChangeStatus updateImpl(Attributor &A) override { | ||||
1979 | const IRPosition &IRP = getIRPosition(); | ||||
1980 | |||||
1981 | const auto &NoFreeAA = A.getAAFor<AANoFree>( | ||||
1982 | *this, IRPosition::function_scope(IRP), DepClassTy::OPTIONAL); | ||||
1983 | if (NoFreeAA.isAssumedNoFree()) | ||||
1984 | return ChangeStatus::UNCHANGED; | ||||
1985 | |||||
1986 | Value &AssociatedValue = getIRPosition().getAssociatedValue(); | ||||
1987 | auto Pred = [&](const Use &U, bool &Follow) -> bool { | ||||
1988 | Instruction *UserI = cast<Instruction>(U.getUser()); | ||||
1989 | if (auto *CB = dyn_cast<CallBase>(UserI)) { | ||||
1990 | if (CB->isBundleOperand(&U)) | ||||
1991 | return false; | ||||
1992 | if (!CB->isArgOperand(&U)) | ||||
1993 | return true; | ||||
1994 | unsigned ArgNo = CB->getArgOperandNo(&U); | ||||
1995 | |||||
1996 | const auto &NoFreeArg = A.getAAFor<AANoFree>( | ||||
1997 | *this, IRPosition::callsite_argument(*CB, ArgNo), | ||||
1998 | DepClassTy::REQUIRED); | ||||
1999 | return NoFreeArg.isAssumedNoFree(); | ||||
2000 | } | ||||
2001 | |||||
2002 | if (isa<GetElementPtrInst>(UserI) || isa<BitCastInst>(UserI) || | ||||
2003 | isa<PHINode>(UserI) || isa<SelectInst>(UserI)) { | ||||
2004 | Follow = true; | ||||
2005 | return true; | ||||
2006 | } | ||||
2007 | if (isa<StoreInst>(UserI) || isa<LoadInst>(UserI) || | ||||
2008 | isa<ReturnInst>(UserI)) | ||||
2009 | return true; | ||||
2010 | |||||
2011 | // Unknown user. | ||||
2012 | return false; | ||||
2013 | }; | ||||
2014 | if (!A.checkForAllUses(Pred, *this, AssociatedValue)) | ||||
2015 | return indicatePessimisticFixpoint(); | ||||
2016 | |||||
2017 | return ChangeStatus::UNCHANGED; | ||||
2018 | } | ||||
2019 | }; | ||||
2020 | |||||
2021 | /// NoFree attribute for a call site argument. | ||||
2022 | struct AANoFreeArgument final : AANoFreeFloating { | ||||
2023 | AANoFreeArgument(const IRPosition &IRP, Attributor &A) | ||||
2024 | : AANoFreeFloating(IRP, A) {} | ||||
2025 | |||||
2026 | /// See AbstractAttribute::trackStatistics() | ||||
2027 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(nofree){ static llvm::Statistic NumIRArguments_nofree = {"attributor" , "NumIRArguments_nofree", ("Number of " "arguments" " marked '" "nofree" "'")};; ++(NumIRArguments_nofree); } } | ||||
2028 | }; | ||||
2029 | |||||
2030 | /// NoFree attribute for call site arguments. | ||||
2031 | struct AANoFreeCallSiteArgument final : AANoFreeFloating { | ||||
2032 | AANoFreeCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
2033 | : AANoFreeFloating(IRP, A) {} | ||||
2034 | |||||
2035 | /// See AbstractAttribute::updateImpl(...). | ||||
2036 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2037 | // TODO: Once we have call site specific value information we can provide | ||||
2038 | // call site specific liveness information and then it makes | ||||
2039 | // sense to specialize attributes for call sites arguments instead of | ||||
2040 | // redirecting requests to the callee argument. | ||||
2041 | Argument *Arg = getAssociatedArgument(); | ||||
2042 | if (!Arg) | ||||
2043 | return indicatePessimisticFixpoint(); | ||||
2044 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||
2045 | auto &ArgAA = A.getAAFor<AANoFree>(*this, ArgPos, DepClassTy::REQUIRED); | ||||
2046 | return clampStateAndIndicateChange(getState(), ArgAA.getState()); | ||||
2047 | } | ||||
2048 | |||||
2049 | /// See AbstractAttribute::trackStatistics() | ||||
2050 | void trackStatistics() const override{STATS_DECLTRACK_CSARG_ATTR(nofree){ static llvm::Statistic NumIRCSArguments_nofree = {"attributor" , "NumIRCSArguments_nofree", ("Number of " "call site arguments" " marked '" "nofree" "'")};; ++(NumIRCSArguments_nofree); }}; | ||||
2051 | }; | ||||
2052 | |||||
2053 | /// NoFree attribute for function return value. | ||||
2054 | struct AANoFreeReturned final : AANoFreeFloating { | ||||
2055 | AANoFreeReturned(const IRPosition &IRP, Attributor &A) | ||||
2056 | : AANoFreeFloating(IRP, A) { | ||||
2057 | llvm_unreachable("NoFree is not applicable to function returns!")__builtin_unreachable(); | ||||
2058 | } | ||||
2059 | |||||
2060 | /// See AbstractAttribute::initialize(...). | ||||
2061 | void initialize(Attributor &A) override { | ||||
2062 | llvm_unreachable("NoFree is not applicable to function returns!")__builtin_unreachable(); | ||||
2063 | } | ||||
2064 | |||||
2065 | /// See AbstractAttribute::updateImpl(...). | ||||
2066 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2067 | llvm_unreachable("NoFree is not applicable to function returns!")__builtin_unreachable(); | ||||
2068 | } | ||||
2069 | |||||
2070 | /// See AbstractAttribute::trackStatistics() | ||||
2071 | void trackStatistics() const override {} | ||||
2072 | }; | ||||
2073 | |||||
2074 | /// NoFree attribute deduction for a call site return value. | ||||
2075 | struct AANoFreeCallSiteReturned final : AANoFreeFloating { | ||||
2076 | AANoFreeCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
2077 | : AANoFreeFloating(IRP, A) {} | ||||
2078 | |||||
2079 | ChangeStatus manifest(Attributor &A) override { | ||||
2080 | return ChangeStatus::UNCHANGED; | ||||
2081 | } | ||||
2082 | /// See AbstractAttribute::trackStatistics() | ||||
2083 | void trackStatistics() const override { STATS_DECLTRACK_CSRET_ATTR(nofree){ static llvm::Statistic NumIRCSReturn_nofree = {"attributor" , "NumIRCSReturn_nofree", ("Number of " "call site returns" " marked '" "nofree" "'")};; ++(NumIRCSReturn_nofree); } } | ||||
2084 | }; | ||||
2085 | |||||
2086 | /// ------------------------ NonNull Argument Attribute ------------------------ | ||||
2087 | static int64_t getKnownNonNullAndDerefBytesForUse( | ||||
2088 | Attributor &A, const AbstractAttribute &QueryingAA, Value &AssociatedValue, | ||||
2089 | const Use *U, const Instruction *I, bool &IsNonNull, bool &TrackUse) { | ||||
2090 | TrackUse = false; | ||||
2091 | |||||
2092 | const Value *UseV = U->get(); | ||||
2093 | if (!UseV->getType()->isPointerTy()) | ||||
2094 | return 0; | ||||
2095 | |||||
2096 | // We need to follow common pointer manipulation uses to the accesses they | ||||
2097 | // feed into. We can try to be smart to avoid looking through things we do not | ||||
2098 | // like for now, e.g., non-inbounds GEPs. | ||||
2099 | if (isa<CastInst>(I)) { | ||||
2100 | TrackUse = true; | ||||
2101 | return 0; | ||||
2102 | } | ||||
2103 | |||||
2104 | if (isa<GetElementPtrInst>(I)) { | ||||
2105 | TrackUse = true; | ||||
2106 | return 0; | ||||
2107 | } | ||||
2108 | |||||
2109 | Type *PtrTy = UseV->getType(); | ||||
2110 | const Function *F = I->getFunction(); | ||||
2111 | bool NullPointerIsDefined = | ||||
2112 | F ? llvm::NullPointerIsDefined(F, PtrTy->getPointerAddressSpace()) : true; | ||||
2113 | const DataLayout &DL = A.getInfoCache().getDL(); | ||||
2114 | if (const auto *CB = dyn_cast<CallBase>(I)) { | ||||
2115 | if (CB->isBundleOperand(U)) { | ||||
2116 | if (RetainedKnowledge RK = getKnowledgeFromUse( | ||||
2117 | U, {Attribute::NonNull, Attribute::Dereferenceable})) { | ||||
2118 | IsNonNull |= | ||||
2119 | (RK.AttrKind == Attribute::NonNull || !NullPointerIsDefined); | ||||
2120 | return RK.ArgValue; | ||||
2121 | } | ||||
2122 | return 0; | ||||
2123 | } | ||||
2124 | |||||
2125 | if (CB->isCallee(U)) { | ||||
2126 | IsNonNull |= !NullPointerIsDefined; | ||||
2127 | return 0; | ||||
2128 | } | ||||
2129 | |||||
2130 | unsigned ArgNo = CB->getArgOperandNo(U); | ||||
2131 | IRPosition IRP = IRPosition::callsite_argument(*CB, ArgNo); | ||||
2132 | // As long as we only use known information there is no need to track | ||||
2133 | // dependences here. | ||||
2134 | auto &DerefAA = | ||||
2135 | A.getAAFor<AADereferenceable>(QueryingAA, IRP, DepClassTy::NONE); | ||||
2136 | IsNonNull |= DerefAA.isKnownNonNull(); | ||||
2137 | return DerefAA.getKnownDereferenceableBytes(); | ||||
2138 | } | ||||
2139 | |||||
2140 | int64_t Offset; | ||||
2141 | const Value *Base = | ||||
2142 | getMinimalBaseOfAccsesPointerOperand(A, QueryingAA, I, Offset, DL); | ||||
2143 | if (Base) { | ||||
2144 | if (Base == &AssociatedValue && | ||||
2145 | getPointerOperand(I, /* AllowVolatile */ false) == UseV) { | ||||
2146 | int64_t DerefBytes = | ||||
2147 | (int64_t)DL.getTypeStoreSize(PtrTy->getPointerElementType()) + Offset; | ||||
2148 | |||||
2149 | IsNonNull |= !NullPointerIsDefined; | ||||
2150 | return std::max(int64_t(0), DerefBytes); | ||||
2151 | } | ||||
2152 | } | ||||
2153 | |||||
2154 | /// Corner case when an offset is 0. | ||||
2155 | Base = getBasePointerOfAccessPointerOperand(I, Offset, DL, | ||||
2156 | /*AllowNonInbounds*/ true); | ||||
2157 | if (Base) { | ||||
2158 | if (Offset == 0 && Base == &AssociatedValue && | ||||
2159 | getPointerOperand(I, /* AllowVolatile */ false) == UseV) { | ||||
2160 | int64_t DerefBytes = | ||||
2161 | (int64_t)DL.getTypeStoreSize(PtrTy->getPointerElementType()); | ||||
2162 | IsNonNull |= !NullPointerIsDefined; | ||||
2163 | return std::max(int64_t(0), DerefBytes); | ||||
2164 | } | ||||
2165 | } | ||||
2166 | |||||
2167 | return 0; | ||||
2168 | } | ||||
2169 | |||||
2170 | struct AANonNullImpl : AANonNull { | ||||
2171 | AANonNullImpl(const IRPosition &IRP, Attributor &A) | ||||
2172 | : AANonNull(IRP, A), | ||||
2173 | NullIsDefined(NullPointerIsDefined( | ||||
2174 | getAnchorScope(), | ||||
2175 | getAssociatedValue().getType()->getPointerAddressSpace())) {} | ||||
2176 | |||||
2177 | /// See AbstractAttribute::initialize(...). | ||||
2178 | void initialize(Attributor &A) override { | ||||
2179 | Value &V = getAssociatedValue(); | ||||
2180 | if (!NullIsDefined && | ||||
2181 | hasAttr({Attribute::NonNull, Attribute::Dereferenceable}, | ||||
2182 | /* IgnoreSubsumingPositions */ false, &A)) { | ||||
2183 | indicateOptimisticFixpoint(); | ||||
2184 | return; | ||||
2185 | } | ||||
2186 | |||||
2187 | if (isa<ConstantPointerNull>(V)) { | ||||
2188 | indicatePessimisticFixpoint(); | ||||
2189 | return; | ||||
2190 | } | ||||
2191 | |||||
2192 | AANonNull::initialize(A); | ||||
2193 | |||||
2194 | bool CanBeNull, CanBeFreed; | ||||
2195 | if (V.getPointerDereferenceableBytes(A.getDataLayout(), CanBeNull, | ||||
2196 | CanBeFreed)) { | ||||
2197 | if (!CanBeNull) { | ||||
2198 | indicateOptimisticFixpoint(); | ||||
2199 | return; | ||||
2200 | } | ||||
2201 | } | ||||
2202 | |||||
2203 | if (isa<GlobalValue>(&getAssociatedValue())) { | ||||
2204 | indicatePessimisticFixpoint(); | ||||
2205 | return; | ||||
2206 | } | ||||
2207 | |||||
2208 | if (Instruction *CtxI = getCtxI()) | ||||
2209 | followUsesInMBEC(*this, A, getState(), *CtxI); | ||||
2210 | } | ||||
2211 | |||||
2212 | /// See followUsesInMBEC | ||||
2213 | bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I, | ||||
2214 | AANonNull::StateType &State) { | ||||
2215 | bool IsNonNull = false; | ||||
2216 | bool TrackUse = false; | ||||
2217 | getKnownNonNullAndDerefBytesForUse(A, *this, getAssociatedValue(), U, I, | ||||
2218 | IsNonNull, TrackUse); | ||||
2219 | State.setKnown(IsNonNull); | ||||
2220 | return TrackUse; | ||||
2221 | } | ||||
2222 | |||||
2223 | /// See AbstractAttribute::getAsStr(). | ||||
2224 | const std::string getAsStr() const override { | ||||
2225 | return getAssumed() ? "nonnull" : "may-null"; | ||||
2226 | } | ||||
2227 | |||||
2228 | /// Flag to determine if the underlying value can be null and still allow | ||||
2229 | /// valid accesses. | ||||
2230 | const bool NullIsDefined; | ||||
2231 | }; | ||||
2232 | |||||
2233 | /// NonNull attribute for a floating value. | ||||
2234 | struct AANonNullFloating : public AANonNullImpl { | ||||
2235 | AANonNullFloating(const IRPosition &IRP, Attributor &A) | ||||
2236 | : AANonNullImpl(IRP, A) {} | ||||
2237 | |||||
2238 | /// See AbstractAttribute::updateImpl(...). | ||||
2239 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2240 | const DataLayout &DL = A.getDataLayout(); | ||||
2241 | |||||
2242 | DominatorTree *DT = nullptr; | ||||
2243 | AssumptionCache *AC = nullptr; | ||||
2244 | InformationCache &InfoCache = A.getInfoCache(); | ||||
2245 | if (const Function *Fn = getAnchorScope()) { | ||||
2246 | DT = InfoCache.getAnalysisResultForFunction<DominatorTreeAnalysis>(*Fn); | ||||
2247 | AC = InfoCache.getAnalysisResultForFunction<AssumptionAnalysis>(*Fn); | ||||
2248 | } | ||||
2249 | |||||
2250 | auto VisitValueCB = [&](Value &V, const Instruction *CtxI, | ||||
2251 | AANonNull::StateType &T, bool Stripped) -> bool { | ||||
2252 | const auto &AA = A.getAAFor<AANonNull>(*this, IRPosition::value(V), | ||||
2253 | DepClassTy::REQUIRED); | ||||
2254 | if (!Stripped && this == &AA) { | ||||
2255 | if (!isKnownNonZero(&V, DL, 0, AC, CtxI, DT)) | ||||
2256 | T.indicatePessimisticFixpoint(); | ||||
2257 | } else { | ||||
2258 | // Use abstract attribute information. | ||||
2259 | const AANonNull::StateType &NS = AA.getState(); | ||||
2260 | T ^= NS; | ||||
2261 | } | ||||
2262 | return T.isValidState(); | ||||
2263 | }; | ||||
2264 | |||||
2265 | StateType T; | ||||
2266 | if (!genericValueTraversal<StateType>(A, getIRPosition(), *this, T, | ||||
2267 | VisitValueCB, getCtxI())) | ||||
2268 | return indicatePessimisticFixpoint(); | ||||
2269 | |||||
2270 | return clampStateAndIndicateChange(getState(), T); | ||||
2271 | } | ||||
2272 | |||||
2273 | /// See AbstractAttribute::trackStatistics() | ||||
2274 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(nonnull){ static llvm::Statistic NumIRFunctionReturn_nonnull = {"attributor" , "NumIRFunctionReturn_nonnull", ("Number of " "function returns" " marked '" "nonnull" "'")};; ++(NumIRFunctionReturn_nonnull ); } } | ||||
2275 | }; | ||||
2276 | |||||
2277 | /// NonNull attribute for function return value. | ||||
2278 | struct AANonNullReturned final | ||||
2279 | : AAReturnedFromReturnedValues<AANonNull, AANonNull> { | ||||
2280 | AANonNullReturned(const IRPosition &IRP, Attributor &A) | ||||
2281 | : AAReturnedFromReturnedValues<AANonNull, AANonNull>(IRP, A) {} | ||||
2282 | |||||
2283 | /// See AbstractAttribute::getAsStr(). | ||||
2284 | const std::string getAsStr() const override { | ||||
2285 | return getAssumed() ? "nonnull" : "may-null"; | ||||
2286 | } | ||||
2287 | |||||
2288 | /// See AbstractAttribute::trackStatistics() | ||||
2289 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(nonnull){ static llvm::Statistic NumIRFunctionReturn_nonnull = {"attributor" , "NumIRFunctionReturn_nonnull", ("Number of " "function returns" " marked '" "nonnull" "'")};; ++(NumIRFunctionReturn_nonnull ); } } | ||||
2290 | }; | ||||
2291 | |||||
2292 | /// NonNull attribute for function argument. | ||||
2293 | struct AANonNullArgument final | ||||
2294 | : AAArgumentFromCallSiteArguments<AANonNull, AANonNullImpl> { | ||||
2295 | AANonNullArgument(const IRPosition &IRP, Attributor &A) | ||||
2296 | : AAArgumentFromCallSiteArguments<AANonNull, AANonNullImpl>(IRP, A) {} | ||||
2297 | |||||
2298 | /// See AbstractAttribute::trackStatistics() | ||||
2299 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(nonnull){ static llvm::Statistic NumIRArguments_nonnull = {"attributor" , "NumIRArguments_nonnull", ("Number of " "arguments" " marked '" "nonnull" "'")};; ++(NumIRArguments_nonnull); } } | ||||
2300 | }; | ||||
2301 | |||||
2302 | struct AANonNullCallSiteArgument final : AANonNullFloating { | ||||
2303 | AANonNullCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
2304 | : AANonNullFloating(IRP, A) {} | ||||
2305 | |||||
2306 | /// See AbstractAttribute::trackStatistics() | ||||
2307 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(nonnull){ static llvm::Statistic NumIRCSArguments_nonnull = {"attributor" , "NumIRCSArguments_nonnull", ("Number of " "call site arguments" " marked '" "nonnull" "'")};; ++(NumIRCSArguments_nonnull); } } | ||||
2308 | }; | ||||
2309 | |||||
2310 | /// NonNull attribute for a call site return position. | ||||
2311 | struct AANonNullCallSiteReturned final | ||||
2312 | : AACallSiteReturnedFromReturned<AANonNull, AANonNullImpl> { | ||||
2313 | AANonNullCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
2314 | : AACallSiteReturnedFromReturned<AANonNull, AANonNullImpl>(IRP, A) {} | ||||
2315 | |||||
2316 | /// See AbstractAttribute::trackStatistics() | ||||
2317 | void trackStatistics() const override { STATS_DECLTRACK_CSRET_ATTR(nonnull){ static llvm::Statistic NumIRCSReturn_nonnull = {"attributor" , "NumIRCSReturn_nonnull", ("Number of " "call site returns" " marked '" "nonnull" "'")};; ++(NumIRCSReturn_nonnull); } } | ||||
2318 | }; | ||||
2319 | |||||
2320 | /// ------------------------ No-Recurse Attributes ---------------------------- | ||||
2321 | |||||
2322 | struct AANoRecurseImpl : public AANoRecurse { | ||||
2323 | AANoRecurseImpl(const IRPosition &IRP, Attributor &A) : AANoRecurse(IRP, A) {} | ||||
2324 | |||||
2325 | /// See AbstractAttribute::getAsStr() | ||||
2326 | const std::string getAsStr() const override { | ||||
2327 | return getAssumed() ? "norecurse" : "may-recurse"; | ||||
2328 | } | ||||
2329 | }; | ||||
2330 | |||||
2331 | struct AANoRecurseFunction final : AANoRecurseImpl { | ||||
2332 | AANoRecurseFunction(const IRPosition &IRP, Attributor &A) | ||||
2333 | : AANoRecurseImpl(IRP, A) {} | ||||
2334 | |||||
2335 | /// See AbstractAttribute::initialize(...). | ||||
2336 | void initialize(Attributor &A) override { | ||||
2337 | AANoRecurseImpl::initialize(A); | ||||
2338 | if (const Function *F = getAnchorScope()) | ||||
2339 | if (A.getInfoCache().getSccSize(*F) != 1) | ||||
2340 | indicatePessimisticFixpoint(); | ||||
2341 | } | ||||
2342 | |||||
2343 | /// See AbstractAttribute::updateImpl(...). | ||||
2344 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2345 | |||||
2346 | // If all live call sites are known to be no-recurse, we are as well. | ||||
2347 | auto CallSitePred = [&](AbstractCallSite ACS) { | ||||
2348 | const auto &NoRecurseAA = A.getAAFor<AANoRecurse>( | ||||
2349 | *this, IRPosition::function(*ACS.getInstruction()->getFunction()), | ||||
2350 | DepClassTy::NONE); | ||||
2351 | return NoRecurseAA.isKnownNoRecurse(); | ||||
2352 | }; | ||||
2353 | bool AllCallSitesKnown; | ||||
2354 | if (A.checkForAllCallSites(CallSitePred, *this, true, AllCallSitesKnown)) { | ||||
2355 | // If we know all call sites and all are known no-recurse, we are done. | ||||
2356 | // If all known call sites, which might not be all that exist, are known | ||||
2357 | // to be no-recurse, we are not done but we can continue to assume | ||||
2358 | // no-recurse. If one of the call sites we have not visited will become | ||||
2359 | // live, another update is triggered. | ||||
2360 | if (AllCallSitesKnown) | ||||
2361 | indicateOptimisticFixpoint(); | ||||
2362 | return ChangeStatus::UNCHANGED; | ||||
2363 | } | ||||
2364 | |||||
2365 | // If the above check does not hold anymore we look at the calls. | ||||
2366 | auto CheckForNoRecurse = [&](Instruction &I) { | ||||
2367 | const auto &CB = cast<CallBase>(I); | ||||
2368 | if (CB.hasFnAttr(Attribute::NoRecurse)) | ||||
2369 | return true; | ||||
2370 | |||||
2371 | const auto &NoRecurseAA = A.getAAFor<AANoRecurse>( | ||||
2372 | *this, IRPosition::callsite_function(CB), DepClassTy::REQUIRED); | ||||
2373 | if (!NoRecurseAA.isAssumedNoRecurse()) | ||||
2374 | return false; | ||||
2375 | |||||
2376 | // Recursion to the same function | ||||
2377 | if (CB.getCalledFunction() == getAnchorScope()) | ||||
2378 | return false; | ||||
2379 | |||||
2380 | return true; | ||||
2381 | }; | ||||
2382 | |||||
2383 | bool UsedAssumedInformation = false; | ||||
2384 | if (!A.checkForAllCallLikeInstructions(CheckForNoRecurse, *this, | ||||
2385 | UsedAssumedInformation)) | ||||
2386 | return indicatePessimisticFixpoint(); | ||||
2387 | return ChangeStatus::UNCHANGED; | ||||
2388 | } | ||||
2389 | |||||
2390 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(norecurse){ static llvm::Statistic NumIRFunction_norecurse = {"attributor" , "NumIRFunction_norecurse", ("Number of " "functions" " marked '" "norecurse" "'")};; ++(NumIRFunction_norecurse); } } | ||||
2391 | }; | ||||
2392 | |||||
2393 | /// NoRecurse attribute deduction for a call sites. | ||||
2394 | struct AANoRecurseCallSite final : AANoRecurseImpl { | ||||
2395 | AANoRecurseCallSite(const IRPosition &IRP, Attributor &A) | ||||
2396 | : AANoRecurseImpl(IRP, A) {} | ||||
2397 | |||||
2398 | /// See AbstractAttribute::initialize(...). | ||||
2399 | void initialize(Attributor &A) override { | ||||
2400 | AANoRecurseImpl::initialize(A); | ||||
2401 | Function *F = getAssociatedFunction(); | ||||
2402 | if (!F || F->isDeclaration()) | ||||
2403 | indicatePessimisticFixpoint(); | ||||
2404 | } | ||||
2405 | |||||
2406 | /// See AbstractAttribute::updateImpl(...). | ||||
2407 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2408 | // TODO: Once we have call site specific value information we can provide | ||||
2409 | // call site specific liveness information and then it makes | ||||
2410 | // sense to specialize attributes for call sites arguments instead of | ||||
2411 | // redirecting requests to the callee argument. | ||||
2412 | Function *F = getAssociatedFunction(); | ||||
2413 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
2414 | auto &FnAA = A.getAAFor<AANoRecurse>(*this, FnPos, DepClassTy::REQUIRED); | ||||
2415 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||
2416 | } | ||||
2417 | |||||
2418 | /// See AbstractAttribute::trackStatistics() | ||||
2419 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(norecurse){ static llvm::Statistic NumIRCS_norecurse = {"attributor", "NumIRCS_norecurse" , ("Number of " "call site" " marked '" "norecurse" "'")};; ++ (NumIRCS_norecurse); }; } | ||||
2420 | }; | ||||
2421 | |||||
2422 | /// -------------------- Undefined-Behavior Attributes ------------------------ | ||||
2423 | |||||
2424 | struct AAUndefinedBehaviorImpl : public AAUndefinedBehavior { | ||||
2425 | AAUndefinedBehaviorImpl(const IRPosition &IRP, Attributor &A) | ||||
2426 | : AAUndefinedBehavior(IRP, A) {} | ||||
2427 | |||||
2428 | /// See AbstractAttribute::updateImpl(...). | ||||
2429 | // through a pointer (i.e. also branches etc.) | ||||
2430 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2431 | const size_t UBPrevSize = KnownUBInsts.size(); | ||||
2432 | const size_t NoUBPrevSize = AssumedNoUBInsts.size(); | ||||
2433 | |||||
2434 | auto InspectMemAccessInstForUB = [&](Instruction &I) { | ||||
2435 | // Lang ref now states volatile store is not UB, let's skip them. | ||||
2436 | if (I.isVolatile() && I.mayWriteToMemory()) | ||||
2437 | return true; | ||||
2438 | |||||
2439 | // Skip instructions that are already saved. | ||||
2440 | if (AssumedNoUBInsts.count(&I) || KnownUBInsts.count(&I)) | ||||
2441 | return true; | ||||
2442 | |||||
2443 | // If we reach here, we know we have an instruction | ||||
2444 | // that accesses memory through a pointer operand, | ||||
2445 | // for which getPointerOperand() should give it to us. | ||||
2446 | Value *PtrOp = | ||||
2447 | const_cast<Value *>(getPointerOperand(&I, /* AllowVolatile */ true)); | ||||
2448 | assert(PtrOp &&(static_cast<void> (0)) | ||||
2449 | "Expected pointer operand of memory accessing instruction")(static_cast<void> (0)); | ||||
2450 | |||||
2451 | // Either we stopped and the appropriate action was taken, | ||||
2452 | // or we got back a simplified value to continue. | ||||
2453 | Optional<Value *> SimplifiedPtrOp = stopOnUndefOrAssumed(A, PtrOp, &I); | ||||
2454 | if (!SimplifiedPtrOp.hasValue() || !SimplifiedPtrOp.getValue()) | ||||
2455 | return true; | ||||
2456 | const Value *PtrOpVal = SimplifiedPtrOp.getValue(); | ||||
2457 | |||||
2458 | // A memory access through a pointer is considered UB | ||||
2459 | // only if the pointer has constant null value. | ||||
2460 | // TODO: Expand it to not only check constant values. | ||||
2461 | if (!isa<ConstantPointerNull>(PtrOpVal)) { | ||||
2462 | AssumedNoUBInsts.insert(&I); | ||||
2463 | return true; | ||||
2464 | } | ||||
2465 | const Type *PtrTy = PtrOpVal->getType(); | ||||
2466 | |||||
2467 | // Because we only consider instructions inside functions, | ||||
2468 | // assume that a parent function exists. | ||||
2469 | const Function *F = I.getFunction(); | ||||
2470 | |||||
2471 | // A memory access using constant null pointer is only considered UB | ||||
2472 | // if null pointer is _not_ defined for the target platform. | ||||
2473 | if (llvm::NullPointerIsDefined(F, PtrTy->getPointerAddressSpace())) | ||||
2474 | AssumedNoUBInsts.insert(&I); | ||||
2475 | else | ||||
2476 | KnownUBInsts.insert(&I); | ||||
2477 | return true; | ||||
2478 | }; | ||||
2479 | |||||
2480 | auto InspectBrInstForUB = [&](Instruction &I) { | ||||
2481 | // A conditional branch instruction is considered UB if it has `undef` | ||||
2482 | // condition. | ||||
2483 | |||||
2484 | // Skip instructions that are already saved. | ||||
2485 | if (AssumedNoUBInsts.count(&I) || KnownUBInsts.count(&I)) | ||||
2486 | return true; | ||||
2487 | |||||
2488 | // We know we have a branch instruction. | ||||
2489 | auto *BrInst = cast<BranchInst>(&I); | ||||
2490 | |||||
2491 | // Unconditional branches are never considered UB. | ||||
2492 | if (BrInst->isUnconditional()) | ||||
2493 | return true; | ||||
2494 | |||||
2495 | // Either we stopped and the appropriate action was taken, | ||||
2496 | // or we got back a simplified value to continue. | ||||
2497 | Optional<Value *> SimplifiedCond = | ||||
2498 | stopOnUndefOrAssumed(A, BrInst->getCondition(), BrInst); | ||||
2499 | if (!SimplifiedCond.hasValue() || !SimplifiedCond.getValue()) | ||||
2500 | return true; | ||||
2501 | AssumedNoUBInsts.insert(&I); | ||||
2502 | return true; | ||||
2503 | }; | ||||
2504 | |||||
2505 | auto InspectCallSiteForUB = [&](Instruction &I) { | ||||
2506 | // Check whether a callsite always cause UB or not | ||||
2507 | |||||
2508 | // Skip instructions that are already saved. | ||||
2509 | if (AssumedNoUBInsts.count(&I) || KnownUBInsts.count(&I)) | ||||
2510 | return true; | ||||
2511 | |||||
2512 | // Check nonnull and noundef argument attribute violation for each | ||||
2513 | // callsite. | ||||
2514 | CallBase &CB = cast<CallBase>(I); | ||||
2515 | Function *Callee = CB.getCalledFunction(); | ||||
2516 | if (!Callee) | ||||
2517 | return true; | ||||
2518 | for (unsigned idx = 0; idx < CB.getNumArgOperands(); idx++) { | ||||
2519 | // If current argument is known to be simplified to null pointer and the | ||||
2520 | // corresponding argument position is known to have nonnull attribute, | ||||
2521 | // the argument is poison. Furthermore, if the argument is poison and | ||||
2522 | // the position is known to have noundef attriubte, this callsite is | ||||
2523 | // considered UB. | ||||
2524 | if (idx >= Callee->arg_size()) | ||||
2525 | break; | ||||
2526 | Value *ArgVal = CB.getArgOperand(idx); | ||||
2527 | if (!ArgVal) | ||||
2528 | continue; | ||||
2529 | // Here, we handle three cases. | ||||
2530 | // (1) Not having a value means it is dead. (we can replace the value | ||||
2531 | // with undef) | ||||
2532 | // (2) Simplified to undef. The argument violate noundef attriubte. | ||||
2533 | // (3) Simplified to null pointer where known to be nonnull. | ||||
2534 | // The argument is a poison value and violate noundef attribute. | ||||
2535 | IRPosition CalleeArgumentIRP = IRPosition::callsite_argument(CB, idx); | ||||
2536 | auto &NoUndefAA = | ||||
2537 | A.getAAFor<AANoUndef>(*this, CalleeArgumentIRP, DepClassTy::NONE); | ||||
2538 | if (!NoUndefAA.isKnownNoUndef()) | ||||
2539 | continue; | ||||
2540 | bool UsedAssumedInformation = false; | ||||
2541 | Optional<Value *> SimplifiedVal = A.getAssumedSimplified( | ||||
2542 | IRPosition::value(*ArgVal), *this, UsedAssumedInformation); | ||||
2543 | if (UsedAssumedInformation) | ||||
2544 | continue; | ||||
2545 | if (SimplifiedVal.hasValue() && !SimplifiedVal.getValue()) | ||||
2546 | return true; | ||||
2547 | if (!SimplifiedVal.hasValue() || | ||||
2548 | isa<UndefValue>(*SimplifiedVal.getValue())) { | ||||
2549 | KnownUBInsts.insert(&I); | ||||
2550 | continue; | ||||
2551 | } | ||||
2552 | if (!ArgVal->getType()->isPointerTy() || | ||||
2553 | !isa<ConstantPointerNull>(*SimplifiedVal.getValue())) | ||||
2554 | continue; | ||||
2555 | auto &NonNullAA = | ||||
2556 | A.getAAFor<AANonNull>(*this, CalleeArgumentIRP, DepClassTy::NONE); | ||||
2557 | if (NonNullAA.isKnownNonNull()) | ||||
2558 | KnownUBInsts.insert(&I); | ||||
2559 | } | ||||
2560 | return true; | ||||
2561 | }; | ||||
2562 | |||||
2563 | auto InspectReturnInstForUB = | ||||
2564 | [&](Value &V, const SmallSetVector<ReturnInst *, 4> RetInsts) { | ||||
2565 | // Check if a return instruction always cause UB or not | ||||
2566 | // Note: It is guaranteed that the returned position of the anchor | ||||
2567 | // scope has noundef attribute when this is called. | ||||
2568 | // We also ensure the return position is not "assumed dead" | ||||
2569 | // because the returned value was then potentially simplified to | ||||
2570 | // `undef` in AAReturnedValues without removing the `noundef` | ||||
2571 | // attribute yet. | ||||
2572 | |||||
2573 | // When the returned position has noundef attriubte, UB occur in the | ||||
2574 | // following cases. | ||||
2575 | // (1) Returned value is known to be undef. | ||||
2576 | // (2) The value is known to be a null pointer and the returned | ||||
2577 | // position has nonnull attribute (because the returned value is | ||||
2578 | // poison). | ||||
2579 | bool FoundUB = false; | ||||
2580 | if (isa<UndefValue>(V)) { | ||||
2581 | FoundUB = true; | ||||
2582 | } else { | ||||
2583 | if (isa<ConstantPointerNull>(V)) { | ||||
2584 | auto &NonNullAA = A.getAAFor<AANonNull>( | ||||
2585 | *this, IRPosition::returned(*getAnchorScope()), | ||||
2586 | DepClassTy::NONE); | ||||
2587 | if (NonNullAA.isKnownNonNull()) | ||||
2588 | FoundUB = true; | ||||
2589 | } | ||||
2590 | } | ||||
2591 | |||||
2592 | if (FoundUB) | ||||
2593 | for (ReturnInst *RI : RetInsts) | ||||
2594 | KnownUBInsts.insert(RI); | ||||
2595 | return true; | ||||
2596 | }; | ||||
2597 | |||||
2598 | bool UsedAssumedInformation = false; | ||||
2599 | A.checkForAllInstructions(InspectMemAccessInstForUB, *this, | ||||
2600 | {Instruction::Load, Instruction::Store, | ||||
2601 | Instruction::AtomicCmpXchg, | ||||
2602 | Instruction::AtomicRMW}, | ||||
2603 | UsedAssumedInformation, | ||||
2604 | /* CheckBBLivenessOnly */ true); | ||||
2605 | A.checkForAllInstructions(InspectBrInstForUB, *this, {Instruction::Br}, | ||||
2606 | UsedAssumedInformation, | ||||
2607 | /* CheckBBLivenessOnly */ true); | ||||
2608 | A.checkForAllCallLikeInstructions(InspectCallSiteForUB, *this, | ||||
2609 | UsedAssumedInformation); | ||||
2610 | |||||
2611 | // If the returned position of the anchor scope has noundef attriubte, check | ||||
2612 | // all returned instructions. | ||||
2613 | if (!getAnchorScope()->getReturnType()->isVoidTy()) { | ||||
2614 | const IRPosition &ReturnIRP = IRPosition::returned(*getAnchorScope()); | ||||
2615 | if (!A.isAssumedDead(ReturnIRP, this, nullptr, UsedAssumedInformation)) { | ||||
2616 | auto &RetPosNoUndefAA = | ||||
2617 | A.getAAFor<AANoUndef>(*this, ReturnIRP, DepClassTy::NONE); | ||||
2618 | if (RetPosNoUndefAA.isKnownNoUndef()) | ||||
2619 | A.checkForAllReturnedValuesAndReturnInsts(InspectReturnInstForUB, | ||||
2620 | *this); | ||||
2621 | } | ||||
2622 | } | ||||
2623 | |||||
2624 | if (NoUBPrevSize != AssumedNoUBInsts.size() || | ||||
2625 | UBPrevSize != KnownUBInsts.size()) | ||||
2626 | return ChangeStatus::CHANGED; | ||||
2627 | return ChangeStatus::UNCHANGED; | ||||
2628 | } | ||||
2629 | |||||
2630 | bool isKnownToCauseUB(Instruction *I) const override { | ||||
2631 | return KnownUBInsts.count(I); | ||||
2632 | } | ||||
2633 | |||||
2634 | bool isAssumedToCauseUB(Instruction *I) const override { | ||||
2635 | // In simple words, if an instruction is not in the assumed to _not_ | ||||
2636 | // cause UB, then it is assumed UB (that includes those | ||||
2637 | // in the KnownUBInsts set). The rest is boilerplate | ||||
2638 | // is to ensure that it is one of the instructions we test | ||||
2639 | // for UB. | ||||
2640 | |||||
2641 | switch (I->getOpcode()) { | ||||
2642 | case Instruction::Load: | ||||
2643 | case Instruction::Store: | ||||
2644 | case Instruction::AtomicCmpXchg: | ||||
2645 | case Instruction::AtomicRMW: | ||||
2646 | return !AssumedNoUBInsts.count(I); | ||||
2647 | case Instruction::Br: { | ||||
2648 | auto BrInst = cast<BranchInst>(I); | ||||
2649 | if (BrInst->isUnconditional()) | ||||
2650 | return false; | ||||
2651 | return !AssumedNoUBInsts.count(I); | ||||
2652 | } break; | ||||
2653 | default: | ||||
2654 | return false; | ||||
2655 | } | ||||
2656 | return false; | ||||
2657 | } | ||||
2658 | |||||
2659 | ChangeStatus manifest(Attributor &A) override { | ||||
2660 | if (KnownUBInsts.empty()) | ||||
2661 | return ChangeStatus::UNCHANGED; | ||||
2662 | for (Instruction *I : KnownUBInsts) | ||||
2663 | A.changeToUnreachableAfterManifest(I); | ||||
2664 | return ChangeStatus::CHANGED; | ||||
2665 | } | ||||
2666 | |||||
2667 | /// See AbstractAttribute::getAsStr() | ||||
2668 | const std::string getAsStr() const override { | ||||
2669 | return getAssumed() ? "undefined-behavior" : "no-ub"; | ||||
2670 | } | ||||
2671 | |||||
2672 | /// Note: The correctness of this analysis depends on the fact that the | ||||
2673 | /// following 2 sets will stop changing after some point. | ||||
2674 | /// "Change" here means that their size changes. | ||||
2675 | /// The size of each set is monotonically increasing | ||||
2676 | /// (we only add items to them) and it is upper bounded by the number of | ||||
2677 | /// instructions in the processed function (we can never save more | ||||
2678 | /// elements in either set than this number). Hence, at some point, | ||||
2679 | /// they will stop increasing. | ||||
2680 | /// Consequently, at some point, both sets will have stopped | ||||
2681 | /// changing, effectively making the analysis reach a fixpoint. | ||||
2682 | |||||
2683 | /// Note: These 2 sets are disjoint and an instruction can be considered | ||||
2684 | /// one of 3 things: | ||||
2685 | /// 1) Known to cause UB (AAUndefinedBehavior could prove it) and put it in | ||||
2686 | /// the KnownUBInsts set. | ||||
2687 | /// 2) Assumed to cause UB (in every updateImpl, AAUndefinedBehavior | ||||
2688 | /// has a reason to assume it). | ||||
2689 | /// 3) Assumed to not cause UB. very other instruction - AAUndefinedBehavior | ||||
2690 | /// could not find a reason to assume or prove that it can cause UB, | ||||
2691 | /// hence it assumes it doesn't. We have a set for these instructions | ||||
2692 | /// so that we don't reprocess them in every update. | ||||
2693 | /// Note however that instructions in this set may cause UB. | ||||
2694 | |||||
2695 | protected: | ||||
2696 | /// A set of all live instructions _known_ to cause UB. | ||||
2697 | SmallPtrSet<Instruction *, 8> KnownUBInsts; | ||||
2698 | |||||
2699 | private: | ||||
2700 | /// A set of all the (live) instructions that are assumed to _not_ cause UB. | ||||
2701 | SmallPtrSet<Instruction *, 8> AssumedNoUBInsts; | ||||
2702 | |||||
2703 | // Should be called on updates in which if we're processing an instruction | ||||
2704 | // \p I that depends on a value \p V, one of the following has to happen: | ||||
2705 | // - If the value is assumed, then stop. | ||||
2706 | // - If the value is known but undef, then consider it UB. | ||||
2707 | // - Otherwise, do specific processing with the simplified value. | ||||
2708 | // We return None in the first 2 cases to signify that an appropriate | ||||
2709 | // action was taken and the caller should stop. | ||||
2710 | // Otherwise, we return the simplified value that the caller should | ||||
2711 | // use for specific processing. | ||||
2712 | Optional<Value *> stopOnUndefOrAssumed(Attributor &A, Value *V, | ||||
2713 | Instruction *I) { | ||||
2714 | bool UsedAssumedInformation = false; | ||||
2715 | Optional<Value *> SimplifiedV = A.getAssumedSimplified( | ||||
2716 | IRPosition::value(*V), *this, UsedAssumedInformation); | ||||
2717 | if (!UsedAssumedInformation) { | ||||
2718 | // Don't depend on assumed values. | ||||
2719 | if (!SimplifiedV.hasValue()) { | ||||
2720 | // If it is known (which we tested above) but it doesn't have a value, | ||||
2721 | // then we can assume `undef` and hence the instruction is UB. | ||||
2722 | KnownUBInsts.insert(I); | ||||
2723 | return llvm::None; | ||||
2724 | } | ||||
2725 | if (!SimplifiedV.getValue()) | ||||
2726 | return nullptr; | ||||
2727 | V = *SimplifiedV; | ||||
2728 | } | ||||
2729 | if (isa<UndefValue>(V)) { | ||||
2730 | KnownUBInsts.insert(I); | ||||
2731 | return llvm::None; | ||||
2732 | } | ||||
2733 | return V; | ||||
2734 | } | ||||
2735 | }; | ||||
2736 | |||||
2737 | struct AAUndefinedBehaviorFunction final : AAUndefinedBehaviorImpl { | ||||
2738 | AAUndefinedBehaviorFunction(const IRPosition &IRP, Attributor &A) | ||||
2739 | : AAUndefinedBehaviorImpl(IRP, A) {} | ||||
2740 | |||||
2741 | /// See AbstractAttribute::trackStatistics() | ||||
2742 | void trackStatistics() const override { | ||||
2743 | STATS_DECL(UndefinedBehaviorInstruction, Instruction,static llvm::Statistic NumIRInstruction_UndefinedBehaviorInstruction = {"attributor", "NumIRInstruction_UndefinedBehaviorInstruction" , "Number of instructions known to have UB"};; | ||||
2744 | "Number of instructions known to have UB")static llvm::Statistic NumIRInstruction_UndefinedBehaviorInstruction = {"attributor", "NumIRInstruction_UndefinedBehaviorInstruction" , "Number of instructions known to have UB"};;; | ||||
2745 | BUILD_STAT_NAME(UndefinedBehaviorInstruction, Instruction)NumIRInstruction_UndefinedBehaviorInstruction += | ||||
2746 | KnownUBInsts.size(); | ||||
2747 | } | ||||
2748 | }; | ||||
2749 | |||||
2750 | /// ------------------------ Will-Return Attributes ---------------------------- | ||||
2751 | |||||
2752 | // Helper function that checks whether a function has any cycle which we don't | ||||
2753 | // know if it is bounded or not. | ||||
2754 | // Loops with maximum trip count are considered bounded, any other cycle not. | ||||
2755 | static bool mayContainUnboundedCycle(Function &F, Attributor &A) { | ||||
2756 | ScalarEvolution *SE = | ||||
2757 | A.getInfoCache().getAnalysisResultForFunction<ScalarEvolutionAnalysis>(F); | ||||
2758 | LoopInfo *LI = A.getInfoCache().getAnalysisResultForFunction<LoopAnalysis>(F); | ||||
2759 | // If either SCEV or LoopInfo is not available for the function then we assume | ||||
2760 | // any cycle to be unbounded cycle. | ||||
2761 | // We use scc_iterator which uses Tarjan algorithm to find all the maximal | ||||
2762 | // SCCs.To detect if there's a cycle, we only need to find the maximal ones. | ||||
2763 | if (!SE || !LI) { | ||||
2764 | for (scc_iterator<Function *> SCCI = scc_begin(&F); !SCCI.isAtEnd(); ++SCCI) | ||||
2765 | if (SCCI.hasCycle()) | ||||
2766 | return true; | ||||
2767 | return false; | ||||
2768 | } | ||||
2769 | |||||
2770 | // If there's irreducible control, the function may contain non-loop cycles. | ||||
2771 | if (mayContainIrreducibleControl(F, LI)) | ||||
2772 | return true; | ||||
2773 | |||||
2774 | // Any loop that does not have a max trip count is considered unbounded cycle. | ||||
2775 | for (auto *L : LI->getLoopsInPreorder()) { | ||||
2776 | if (!SE->getSmallConstantMaxTripCount(L)) | ||||
2777 | return true; | ||||
2778 | } | ||||
2779 | return false; | ||||
2780 | } | ||||
2781 | |||||
2782 | struct AAWillReturnImpl : public AAWillReturn { | ||||
2783 | AAWillReturnImpl(const IRPosition &IRP, Attributor &A) | ||||
2784 | : AAWillReturn(IRP, A) {} | ||||
2785 | |||||
2786 | /// See AbstractAttribute::initialize(...). | ||||
2787 | void initialize(Attributor &A) override { | ||||
2788 | AAWillReturn::initialize(A); | ||||
2789 | |||||
2790 | if (isImpliedByMustprogressAndReadonly(A, /* KnownOnly */ true)) { | ||||
2791 | indicateOptimisticFixpoint(); | ||||
2792 | return; | ||||
2793 | } | ||||
2794 | } | ||||
2795 | |||||
2796 | /// Check for `mustprogress` and `readonly` as they imply `willreturn`. | ||||
2797 | bool isImpliedByMustprogressAndReadonly(Attributor &A, bool KnownOnly) { | ||||
2798 | // Check for `mustprogress` in the scope and the associated function which | ||||
2799 | // might be different if this is a call site. | ||||
2800 | if ((!getAnchorScope() || !getAnchorScope()->mustProgress()) && | ||||
2801 | (!getAssociatedFunction() || !getAssociatedFunction()->mustProgress())) | ||||
2802 | return false; | ||||
2803 | |||||
2804 | const auto &MemAA = | ||||
2805 | A.getAAFor<AAMemoryBehavior>(*this, getIRPosition(), DepClassTy::NONE); | ||||
2806 | if (!MemAA.isAssumedReadOnly()) | ||||
2807 | return false; | ||||
2808 | if (KnownOnly && !MemAA.isKnownReadOnly()) | ||||
2809 | return false; | ||||
2810 | if (!MemAA.isKnownReadOnly()) | ||||
2811 | A.recordDependence(MemAA, *this, DepClassTy::OPTIONAL); | ||||
2812 | |||||
2813 | return true; | ||||
2814 | } | ||||
2815 | |||||
2816 | /// See AbstractAttribute::updateImpl(...). | ||||
2817 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2818 | if (isImpliedByMustprogressAndReadonly(A, /* KnownOnly */ false)) | ||||
2819 | return ChangeStatus::UNCHANGED; | ||||
2820 | |||||
2821 | auto CheckForWillReturn = [&](Instruction &I) { | ||||
2822 | IRPosition IPos = IRPosition::callsite_function(cast<CallBase>(I)); | ||||
2823 | const auto &WillReturnAA = | ||||
2824 | A.getAAFor<AAWillReturn>(*this, IPos, DepClassTy::REQUIRED); | ||||
2825 | if (WillReturnAA.isKnownWillReturn()) | ||||
2826 | return true; | ||||
2827 | if (!WillReturnAA.isAssumedWillReturn()) | ||||
2828 | return false; | ||||
2829 | const auto &NoRecurseAA = | ||||
2830 | A.getAAFor<AANoRecurse>(*this, IPos, DepClassTy::REQUIRED); | ||||
2831 | return NoRecurseAA.isAssumedNoRecurse(); | ||||
2832 | }; | ||||
2833 | |||||
2834 | bool UsedAssumedInformation = false; | ||||
2835 | if (!A.checkForAllCallLikeInstructions(CheckForWillReturn, *this, | ||||
2836 | UsedAssumedInformation)) | ||||
2837 | return indicatePessimisticFixpoint(); | ||||
2838 | |||||
2839 | return ChangeStatus::UNCHANGED; | ||||
2840 | } | ||||
2841 | |||||
2842 | /// See AbstractAttribute::getAsStr() | ||||
2843 | const std::string getAsStr() const override { | ||||
2844 | return getAssumed() ? "willreturn" : "may-noreturn"; | ||||
2845 | } | ||||
2846 | }; | ||||
2847 | |||||
2848 | struct AAWillReturnFunction final : AAWillReturnImpl { | ||||
2849 | AAWillReturnFunction(const IRPosition &IRP, Attributor &A) | ||||
2850 | : AAWillReturnImpl(IRP, A) {} | ||||
2851 | |||||
2852 | /// See AbstractAttribute::initialize(...). | ||||
2853 | void initialize(Attributor &A) override { | ||||
2854 | AAWillReturnImpl::initialize(A); | ||||
2855 | |||||
2856 | Function *F = getAnchorScope(); | ||||
2857 | if (!F || F->isDeclaration() || mayContainUnboundedCycle(*F, A)) | ||||
2858 | indicatePessimisticFixpoint(); | ||||
2859 | } | ||||
2860 | |||||
2861 | /// See AbstractAttribute::trackStatistics() | ||||
2862 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(willreturn){ static llvm::Statistic NumIRFunction_willreturn = {"attributor" , "NumIRFunction_willreturn", ("Number of " "functions" " marked '" "willreturn" "'")};; ++(NumIRFunction_willreturn); } } | ||||
2863 | }; | ||||
2864 | |||||
2865 | /// WillReturn attribute deduction for a call sites. | ||||
2866 | struct AAWillReturnCallSite final : AAWillReturnImpl { | ||||
2867 | AAWillReturnCallSite(const IRPosition &IRP, Attributor &A) | ||||
2868 | : AAWillReturnImpl(IRP, A) {} | ||||
2869 | |||||
2870 | /// See AbstractAttribute::initialize(...). | ||||
2871 | void initialize(Attributor &A) override { | ||||
2872 | AAWillReturnImpl::initialize(A); | ||||
2873 | Function *F = getAssociatedFunction(); | ||||
2874 | if (!F || !A.isFunctionIPOAmendable(*F)) | ||||
2875 | indicatePessimisticFixpoint(); | ||||
2876 | } | ||||
2877 | |||||
2878 | /// See AbstractAttribute::updateImpl(...). | ||||
2879 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2880 | if (isImpliedByMustprogressAndReadonly(A, /* KnownOnly */ false)) | ||||
2881 | return ChangeStatus::UNCHANGED; | ||||
2882 | |||||
2883 | // TODO: Once we have call site specific value information we can provide | ||||
2884 | // call site specific liveness information and then it makes | ||||
2885 | // sense to specialize attributes for call sites arguments instead of | ||||
2886 | // redirecting requests to the callee argument. | ||||
2887 | Function *F = getAssociatedFunction(); | ||||
2888 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
2889 | auto &FnAA = A.getAAFor<AAWillReturn>(*this, FnPos, DepClassTy::REQUIRED); | ||||
2890 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||
2891 | } | ||||
2892 | |||||
2893 | /// See AbstractAttribute::trackStatistics() | ||||
2894 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(willreturn){ static llvm::Statistic NumIRCS_willreturn = {"attributor", "NumIRCS_willreturn" , ("Number of " "call site" " marked '" "willreturn" "'")};; ++ (NumIRCS_willreturn); }; } | ||||
2895 | }; | ||||
2896 | |||||
2897 | /// -------------------AAReachability Attribute-------------------------- | ||||
2898 | |||||
2899 | struct AAReachabilityImpl : AAReachability { | ||||
2900 | AAReachabilityImpl(const IRPosition &IRP, Attributor &A) | ||||
2901 | : AAReachability(IRP, A) {} | ||||
2902 | |||||
2903 | const std::string getAsStr() const override { | ||||
2904 | // TODO: Return the number of reachable queries. | ||||
2905 | return "reachable"; | ||||
2906 | } | ||||
2907 | |||||
2908 | /// See AbstractAttribute::updateImpl(...). | ||||
2909 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2910 | return ChangeStatus::UNCHANGED; | ||||
2911 | } | ||||
2912 | }; | ||||
2913 | |||||
2914 | struct AAReachabilityFunction final : public AAReachabilityImpl { | ||||
2915 | AAReachabilityFunction(const IRPosition &IRP, Attributor &A) | ||||
2916 | : AAReachabilityImpl(IRP, A) {} | ||||
2917 | |||||
2918 | /// See AbstractAttribute::trackStatistics() | ||||
2919 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(reachable){ static llvm::Statistic NumIRFunction_reachable = {"attributor" , "NumIRFunction_reachable", ("Number of " "functions" " marked '" "reachable" "'")};; ++(NumIRFunction_reachable); }; } | ||||
2920 | }; | ||||
2921 | |||||
2922 | /// ------------------------ NoAlias Argument Attribute ------------------------ | ||||
2923 | |||||
2924 | struct AANoAliasImpl : AANoAlias { | ||||
2925 | AANoAliasImpl(const IRPosition &IRP, Attributor &A) : AANoAlias(IRP, A) { | ||||
2926 | assert(getAssociatedType()->isPointerTy() &&(static_cast<void> (0)) | ||||
2927 | "Noalias is a pointer attribute")(static_cast<void> (0)); | ||||
2928 | } | ||||
2929 | |||||
2930 | const std::string getAsStr() const override { | ||||
2931 | return getAssumed() ? "noalias" : "may-alias"; | ||||
2932 | } | ||||
2933 | }; | ||||
2934 | |||||
2935 | /// NoAlias attribute for a floating value. | ||||
2936 | struct AANoAliasFloating final : AANoAliasImpl { | ||||
2937 | AANoAliasFloating(const IRPosition &IRP, Attributor &A) | ||||
2938 | : AANoAliasImpl(IRP, A) {} | ||||
2939 | |||||
2940 | /// See AbstractAttribute::initialize(...). | ||||
2941 | void initialize(Attributor &A) override { | ||||
2942 | AANoAliasImpl::initialize(A); | ||||
2943 | Value *Val = &getAssociatedValue(); | ||||
2944 | do { | ||||
2945 | CastInst *CI = dyn_cast<CastInst>(Val); | ||||
2946 | if (!CI) | ||||
2947 | break; | ||||
2948 | Value *Base = CI->getOperand(0); | ||||
2949 | if (!Base->hasOneUse()) | ||||
2950 | break; | ||||
2951 | Val = Base; | ||||
2952 | } while (true); | ||||
2953 | |||||
2954 | if (!Val->getType()->isPointerTy()) { | ||||
2955 | indicatePessimisticFixpoint(); | ||||
2956 | return; | ||||
2957 | } | ||||
2958 | |||||
2959 | if (isa<AllocaInst>(Val)) | ||||
2960 | indicateOptimisticFixpoint(); | ||||
2961 | else if (isa<ConstantPointerNull>(Val) && | ||||
2962 | !NullPointerIsDefined(getAnchorScope(), | ||||
2963 | Val->getType()->getPointerAddressSpace())) | ||||
2964 | indicateOptimisticFixpoint(); | ||||
2965 | else if (Val != &getAssociatedValue()) { | ||||
2966 | const auto &ValNoAliasAA = A.getAAFor<AANoAlias>( | ||||
2967 | *this, IRPosition::value(*Val), DepClassTy::OPTIONAL); | ||||
2968 | if (ValNoAliasAA.isKnownNoAlias()) | ||||
2969 | indicateOptimisticFixpoint(); | ||||
2970 | } | ||||
2971 | } | ||||
2972 | |||||
2973 | /// See AbstractAttribute::updateImpl(...). | ||||
2974 | ChangeStatus updateImpl(Attributor &A) override { | ||||
2975 | // TODO: Implement this. | ||||
2976 | return indicatePessimisticFixpoint(); | ||||
2977 | } | ||||
2978 | |||||
2979 | /// See AbstractAttribute::trackStatistics() | ||||
2980 | void trackStatistics() const override { | ||||
2981 | STATS_DECLTRACK_FLOATING_ATTR(noalias){ static llvm::Statistic NumIRFloating_noalias = {"attributor" , "NumIRFloating_noalias", ("Number of floating values known to be '" "noalias" "'")};; ++(NumIRFloating_noalias); } | ||||
2982 | } | ||||
2983 | }; | ||||
2984 | |||||
2985 | /// NoAlias attribute for an argument. | ||||
2986 | struct AANoAliasArgument final | ||||
2987 | : AAArgumentFromCallSiteArguments<AANoAlias, AANoAliasImpl> { | ||||
2988 | using Base = AAArgumentFromCallSiteArguments<AANoAlias, AANoAliasImpl>; | ||||
2989 | AANoAliasArgument(const IRPosition &IRP, Attributor &A) : Base(IRP, A) {} | ||||
2990 | |||||
2991 | /// See AbstractAttribute::initialize(...). | ||||
2992 | void initialize(Attributor &A) override { | ||||
2993 | Base::initialize(A); | ||||
2994 | // See callsite argument attribute and callee argument attribute. | ||||
2995 | if (hasAttr({Attribute::ByVal})) | ||||
2996 | indicateOptimisticFixpoint(); | ||||
2997 | } | ||||
2998 | |||||
2999 | /// See AbstractAttribute::update(...). | ||||
3000 | ChangeStatus updateImpl(Attributor &A) override { | ||||
3001 | // We have to make sure no-alias on the argument does not break | ||||
3002 | // synchronization when this is a callback argument, see also [1] below. | ||||
3003 | // If synchronization cannot be affected, we delegate to the base updateImpl | ||||
3004 | // function, otherwise we give up for now. | ||||
3005 | |||||
3006 | // If the function is no-sync, no-alias cannot break synchronization. | ||||
3007 | const auto &NoSyncAA = | ||||
3008 | A.getAAFor<AANoSync>(*this, IRPosition::function_scope(getIRPosition()), | ||||
3009 | DepClassTy::OPTIONAL); | ||||
3010 | if (NoSyncAA.isAssumedNoSync()) | ||||
3011 | return Base::updateImpl(A); | ||||
3012 | |||||
3013 | // If the argument is read-only, no-alias cannot break synchronization. | ||||
3014 | const auto &MemBehaviorAA = A.getAAFor<AAMemoryBehavior>( | ||||
3015 | *this, getIRPosition(), DepClassTy::OPTIONAL); | ||||
3016 | if (MemBehaviorAA.isAssumedReadOnly()) | ||||
3017 | return Base::updateImpl(A); | ||||
3018 | |||||
3019 | // If the argument is never passed through callbacks, no-alias cannot break | ||||
3020 | // synchronization. | ||||
3021 | bool AllCallSitesKnown; | ||||
3022 | if (A.checkForAllCallSites( | ||||
3023 | [](AbstractCallSite ACS) { return !ACS.isCallbackCall(); }, *this, | ||||
3024 | true, AllCallSitesKnown)) | ||||
3025 | return Base::updateImpl(A); | ||||
3026 | |||||
3027 | // TODO: add no-alias but make sure it doesn't break synchronization by | ||||
3028 | // introducing fake uses. See: | ||||
3029 | // [1] Compiler Optimizations for OpenMP, J. Doerfert and H. Finkel, | ||||
3030 | // International Workshop on OpenMP 2018, | ||||
3031 | // http://compilers.cs.uni-saarland.de/people/doerfert/par_opt18.pdf | ||||
3032 | |||||
3033 | return indicatePessimisticFixpoint(); | ||||
3034 | } | ||||
3035 | |||||
3036 | /// See AbstractAttribute::trackStatistics() | ||||
3037 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(noalias){ static llvm::Statistic NumIRArguments_noalias = {"attributor" , "NumIRArguments_noalias", ("Number of " "arguments" " marked '" "noalias" "'")};; ++(NumIRArguments_noalias); } } | ||||
3038 | }; | ||||
3039 | |||||
3040 | struct AANoAliasCallSiteArgument final : AANoAliasImpl { | ||||
3041 | AANoAliasCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
3042 | : AANoAliasImpl(IRP, A) {} | ||||
3043 | |||||
3044 | /// See AbstractAttribute::initialize(...). | ||||
3045 | void initialize(Attributor &A) override { | ||||
3046 | // See callsite argument attribute and callee argument attribute. | ||||
3047 | const auto &CB = cast<CallBase>(getAnchorValue()); | ||||
3048 | if (CB.paramHasAttr(getCallSiteArgNo(), Attribute::NoAlias)) | ||||
3049 | indicateOptimisticFixpoint(); | ||||
3050 | Value &Val = getAssociatedValue(); | ||||
3051 | if (isa<ConstantPointerNull>(Val) && | ||||
3052 | !NullPointerIsDefined(getAnchorScope(), | ||||
3053 | Val.getType()->getPointerAddressSpace())) | ||||
3054 | indicateOptimisticFixpoint(); | ||||
3055 | } | ||||
3056 | |||||
3057 | /// Determine if the underlying value may alias with the call site argument | ||||
3058 | /// \p OtherArgNo of \p ICS (= the underlying call site). | ||||
3059 | bool mayAliasWithArgument(Attributor &A, AAResults *&AAR, | ||||
3060 | const AAMemoryBehavior &MemBehaviorAA, | ||||
3061 | const CallBase &CB, unsigned OtherArgNo) { | ||||
3062 | // We do not need to worry about aliasing with the underlying IRP. | ||||
3063 | if (this->getCalleeArgNo() == (int)OtherArgNo) | ||||
3064 | return false; | ||||
3065 | |||||
3066 | // If it is not a pointer or pointer vector we do not alias. | ||||
3067 | const Value *ArgOp = CB.getArgOperand(OtherArgNo); | ||||
3068 | if (!ArgOp->getType()->isPtrOrPtrVectorTy()) | ||||
3069 | return false; | ||||
3070 | |||||
3071 | auto &CBArgMemBehaviorAA = A.getAAFor<AAMemoryBehavior>( | ||||
3072 | *this, IRPosition::callsite_argument(CB, OtherArgNo), DepClassTy::NONE); | ||||
3073 | |||||
3074 | // If the argument is readnone, there is no read-write aliasing. | ||||
3075 | if (CBArgMemBehaviorAA.isAssumedReadNone()) { | ||||
3076 | A.recordDependence(CBArgMemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||
3077 | return false; | ||||
3078 | } | ||||
3079 | |||||
3080 | // If the argument is readonly and the underlying value is readonly, there | ||||
3081 | // is no read-write aliasing. | ||||
3082 | bool IsReadOnly = MemBehaviorAA.isAssumedReadOnly(); | ||||
3083 | if (CBArgMemBehaviorAA.isAssumedReadOnly() && IsReadOnly) { | ||||
3084 | A.recordDependence(MemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||
3085 | A.recordDependence(CBArgMemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||
3086 | return false; | ||||
3087 | } | ||||
3088 | |||||
3089 | // We have to utilize actual alias analysis queries so we need the object. | ||||
3090 | if (!AAR) | ||||
3091 | AAR = A.getInfoCache().getAAResultsForFunction(*getAnchorScope()); | ||||
3092 | |||||
3093 | // Try to rule it out at the call site. | ||||
3094 | bool IsAliasing = !AAR || !AAR->isNoAlias(&getAssociatedValue(), ArgOp); | ||||
3095 | LLVM_DEBUG(dbgs() << "[NoAliasCSArg] Check alias between "do { } while (false) | ||||
3096 | "callsite arguments: "do { } while (false) | ||||
3097 | << getAssociatedValue() << " " << *ArgOp << " => "do { } while (false) | ||||
3098 | << (IsAliasing ? "" : "no-") << "alias \n")do { } while (false); | ||||
3099 | |||||
3100 | return IsAliasing; | ||||
3101 | } | ||||
3102 | |||||
3103 | bool | ||||
3104 | isKnownNoAliasDueToNoAliasPreservation(Attributor &A, AAResults *&AAR, | ||||
3105 | const AAMemoryBehavior &MemBehaviorAA, | ||||
3106 | const AANoAlias &NoAliasAA) { | ||||
3107 | // We can deduce "noalias" if the following conditions hold. | ||||
3108 | // (i) Associated value is assumed to be noalias in the definition. | ||||
3109 | // (ii) Associated value is assumed to be no-capture in all the uses | ||||
3110 | // possibly executed before this callsite. | ||||
3111 | // (iii) There is no other pointer argument which could alias with the | ||||
3112 | // value. | ||||
3113 | |||||
3114 | bool AssociatedValueIsNoAliasAtDef = NoAliasAA.isAssumedNoAlias(); | ||||
3115 | if (!AssociatedValueIsNoAliasAtDef) { | ||||
3116 | LLVM_DEBUG(dbgs() << "[AANoAlias] " << getAssociatedValue()do { } while (false) | ||||
3117 | << " is not no-alias at the definition\n")do { } while (false); | ||||
3118 | return false; | ||||
3119 | } | ||||
3120 | |||||
3121 | A.recordDependence(NoAliasAA, *this, DepClassTy::OPTIONAL); | ||||
3122 | |||||
3123 | const IRPosition &VIRP = IRPosition::value(getAssociatedValue()); | ||||
3124 | const Function *ScopeFn = VIRP.getAnchorScope(); | ||||
3125 | auto &NoCaptureAA = A.getAAFor<AANoCapture>(*this, VIRP, DepClassTy::NONE); | ||||
3126 | // Check whether the value is captured in the scope using AANoCapture. | ||||
3127 | // Look at CFG and check only uses possibly executed before this | ||||
3128 | // callsite. | ||||
3129 | auto UsePred = [&](const Use &U, bool &Follow) -> bool { | ||||
3130 | Instruction *UserI = cast<Instruction>(U.getUser()); | ||||
3131 | |||||
3132 | // If UserI is the curr instruction and there is a single potential use of | ||||
3133 | // the value in UserI we allow the use. | ||||
3134 | // TODO: We should inspect the operands and allow those that cannot alias | ||||
3135 | // with the value. | ||||
3136 | if (UserI == getCtxI() && UserI->getNumOperands() == 1) | ||||
3137 | return true; | ||||
3138 | |||||
3139 | if (ScopeFn) { | ||||
3140 | const auto &ReachabilityAA = A.getAAFor<AAReachability>( | ||||
3141 | *this, IRPosition::function(*ScopeFn), DepClassTy::OPTIONAL); | ||||
3142 | |||||
3143 | if (!ReachabilityAA.isAssumedReachable(A, *UserI, *getCtxI())) | ||||
3144 | return true; | ||||
3145 | |||||
3146 | if (auto *CB = dyn_cast<CallBase>(UserI)) { | ||||
3147 | if (CB->isArgOperand(&U)) { | ||||
3148 | |||||
3149 | unsigned ArgNo = CB->getArgOperandNo(&U); | ||||
3150 | |||||
3151 | const auto &NoCaptureAA = A.getAAFor<AANoCapture>( | ||||
3152 | *this, IRPosition::callsite_argument(*CB, ArgNo), | ||||
3153 | DepClassTy::OPTIONAL); | ||||
3154 | |||||
3155 | if (NoCaptureAA.isAssumedNoCapture()) | ||||
3156 | return true; | ||||
3157 | } | ||||
3158 | } | ||||
3159 | } | ||||
3160 | |||||
3161 | // For cases which can potentially have more users | ||||
3162 | if (isa<GetElementPtrInst>(U) || isa<BitCastInst>(U) || isa<PHINode>(U) || | ||||
3163 | isa<SelectInst>(U)) { | ||||
3164 | Follow = true; | ||||
3165 | return true; | ||||
3166 | } | ||||
3167 | |||||
3168 | LLVM_DEBUG(dbgs() << "[AANoAliasCSArg] Unknown user: " << *U << "\n")do { } while (false); | ||||
3169 | return false; | ||||
3170 | }; | ||||
3171 | |||||
3172 | if (!NoCaptureAA.isAssumedNoCaptureMaybeReturned()) { | ||||
3173 | if (!A.checkForAllUses(UsePred, *this, getAssociatedValue())) { | ||||
3174 | LLVM_DEBUG(do { } while (false) | ||||
3175 | dbgs() << "[AANoAliasCSArg] " << getAssociatedValue()do { } while (false) | ||||
3176 | << " cannot be noalias as it is potentially captured\n")do { } while (false); | ||||
3177 | return false; | ||||
3178 | } | ||||
3179 | } | ||||
3180 | A.recordDependence(NoCaptureAA, *this, DepClassTy::OPTIONAL); | ||||
3181 | |||||
3182 | // Check there is no other pointer argument which could alias with the | ||||
3183 | // value passed at this call site. | ||||
3184 | // TODO: AbstractCallSite | ||||
3185 | const auto &CB = cast<CallBase>(getAnchorValue()); | ||||
3186 | for (unsigned OtherArgNo = 0; OtherArgNo < CB.getNumArgOperands(); | ||||
3187 | OtherArgNo++) | ||||
3188 | if (mayAliasWithArgument(A, AAR, MemBehaviorAA, CB, OtherArgNo)) | ||||
3189 | return false; | ||||
3190 | |||||
3191 | return true; | ||||
3192 | } | ||||
3193 | |||||
3194 | /// See AbstractAttribute::updateImpl(...). | ||||
3195 | ChangeStatus updateImpl(Attributor &A) override { | ||||
3196 | // If the argument is readnone we are done as there are no accesses via the | ||||
3197 | // argument. | ||||
3198 | auto &MemBehaviorAA = | ||||
3199 | A.getAAFor<AAMemoryBehavior>(*this, getIRPosition(), DepClassTy::NONE); | ||||
3200 | if (MemBehaviorAA.isAssumedReadNone()) { | ||||
3201 | A.recordDependence(MemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||
3202 | return ChangeStatus::UNCHANGED; | ||||
3203 | } | ||||
3204 | |||||
3205 | const IRPosition &VIRP = IRPosition::value(getAssociatedValue()); | ||||
3206 | const auto &NoAliasAA = | ||||
3207 | A.getAAFor<AANoAlias>(*this, VIRP, DepClassTy::NONE); | ||||
3208 | |||||
3209 | AAResults *AAR = nullptr; | ||||
3210 | if (isKnownNoAliasDueToNoAliasPreservation(A, AAR, MemBehaviorAA, | ||||
3211 | NoAliasAA)) { | ||||
3212 | LLVM_DEBUG(do { } while (false) | ||||
3213 | dbgs() << "[AANoAlias] No-Alias deduced via no-alias preservation\n")do { } while (false); | ||||
3214 | return ChangeStatus::UNCHANGED; | ||||
3215 | } | ||||
3216 | |||||
3217 | return indicatePessimisticFixpoint(); | ||||
3218 | } | ||||
3219 | |||||
3220 | /// See AbstractAttribute::trackStatistics() | ||||
3221 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(noalias){ static llvm::Statistic NumIRCSArguments_noalias = {"attributor" , "NumIRCSArguments_noalias", ("Number of " "call site arguments" " marked '" "noalias" "'")};; ++(NumIRCSArguments_noalias); } } | ||||
3222 | }; | ||||
3223 | |||||
3224 | /// NoAlias attribute for function return value. | ||||
3225 | struct AANoAliasReturned final : AANoAliasImpl { | ||||
3226 | AANoAliasReturned(const IRPosition &IRP, Attributor &A) | ||||
3227 | : AANoAliasImpl(IRP, A) {} | ||||
3228 | |||||
3229 | /// See AbstractAttribute::initialize(...). | ||||
3230 | void initialize(Attributor &A) override { | ||||
3231 | AANoAliasImpl::initialize(A); | ||||
3232 | Function *F = getAssociatedFunction(); | ||||
3233 | if (!F || F->isDeclaration()) | ||||
3234 | indicatePessimisticFixpoint(); | ||||
3235 | } | ||||
3236 | |||||
3237 | /// See AbstractAttribute::updateImpl(...). | ||||
3238 | virtual ChangeStatus updateImpl(Attributor &A) override { | ||||
3239 | |||||
3240 | auto CheckReturnValue = [&](Value &RV) -> bool { | ||||
3241 | if (Constant *C = dyn_cast<Constant>(&RV)) | ||||
3242 | if (C->isNullValue() || isa<UndefValue>(C)) | ||||
3243 | return true; | ||||
3244 | |||||
3245 | /// For now, we can only deduce noalias if we have call sites. | ||||
3246 | /// FIXME: add more support. | ||||
3247 | if (!isa<CallBase>(&RV)) | ||||
3248 | return false; | ||||
3249 | |||||
3250 | const IRPosition &RVPos = IRPosition::value(RV); | ||||
3251 | const auto &NoAliasAA = | ||||
3252 | A.getAAFor<AANoAlias>(*this, RVPos, DepClassTy::REQUIRED); | ||||
3253 | if (!NoAliasAA.isAssumedNoAlias()) | ||||
3254 | return false; | ||||
3255 | |||||
3256 | const auto &NoCaptureAA = | ||||
3257 | A.getAAFor<AANoCapture>(*this, RVPos, DepClassTy::REQUIRED); | ||||
3258 | return NoCaptureAA.isAssumedNoCaptureMaybeReturned(); | ||||
3259 | }; | ||||
3260 | |||||
3261 | if (!A.checkForAllReturnedValues(CheckReturnValue, *this)) | ||||
3262 | return indicatePessimisticFixpoint(); | ||||
3263 | |||||
3264 | return ChangeStatus::UNCHANGED; | ||||
3265 | } | ||||
3266 | |||||
3267 | /// See AbstractAttribute::trackStatistics() | ||||
3268 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(noalias){ static llvm::Statistic NumIRFunctionReturn_noalias = {"attributor" , "NumIRFunctionReturn_noalias", ("Number of " "function returns" " marked '" "noalias" "'")};; ++(NumIRFunctionReturn_noalias ); } } | ||||
3269 | }; | ||||
3270 | |||||
3271 | /// NoAlias attribute deduction for a call site return value. | ||||
3272 | struct AANoAliasCallSiteReturned final : AANoAliasImpl { | ||||
3273 | AANoAliasCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
3274 | : AANoAliasImpl(IRP, A) {} | ||||
3275 | |||||
3276 | /// See AbstractAttribute::initialize(...). | ||||
3277 | void initialize(Attributor &A) override { | ||||
3278 | AANoAliasImpl::initialize(A); | ||||
3279 | Function *F = getAssociatedFunction(); | ||||
3280 | if (!F || F->isDeclaration()) | ||||
3281 | indicatePessimisticFixpoint(); | ||||
3282 | } | ||||
3283 | |||||
3284 | /// See AbstractAttribute::updateImpl(...). | ||||
3285 | ChangeStatus updateImpl(Attributor &A) override { | ||||
3286 | // TODO: Once we have call site specific value information we can provide | ||||
3287 | // call site specific liveness information and then it makes | ||||
3288 | // sense to specialize attributes for call sites arguments instead of | ||||
3289 | // redirecting requests to the callee argument. | ||||
3290 | Function *F = getAssociatedFunction(); | ||||
3291 | const IRPosition &FnPos = IRPosition::returned(*F); | ||||
3292 | auto &FnAA = A.getAAFor<AANoAlias>(*this, FnPos, DepClassTy::REQUIRED); | ||||
3293 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||
3294 | } | ||||
3295 | |||||
3296 | /// See AbstractAttribute::trackStatistics() | ||||
3297 | void trackStatistics() const override { STATS_DECLTRACK_CSRET_ATTR(noalias){ static llvm::Statistic NumIRCSReturn_noalias = {"attributor" , "NumIRCSReturn_noalias", ("Number of " "call site returns" " marked '" "noalias" "'")};; ++(NumIRCSReturn_noalias); }; } | ||||
3298 | }; | ||||
3299 | |||||
3300 | /// -------------------AAIsDead Function Attribute----------------------- | ||||
3301 | |||||
3302 | struct AAIsDeadValueImpl : public AAIsDead { | ||||
3303 | AAIsDeadValueImpl(const IRPosition &IRP, Attributor &A) : AAIsDead(IRP, A) {} | ||||
3304 | |||||
3305 | /// See AAIsDead::isAssumedDead(). | ||||
3306 | bool isAssumedDead() const override { return isAssumed(IS_DEAD); } | ||||
3307 | |||||
3308 | /// See AAIsDead::isKnownDead(). | ||||
3309 | bool isKnownDead() const override { return isKnown(IS_DEAD); } | ||||
3310 | |||||
3311 | /// See AAIsDead::isAssumedDead(BasicBlock *). | ||||
3312 | bool isAssumedDead(const BasicBlock *BB) const override { return false; } | ||||
3313 | |||||
3314 | /// See AAIsDead::isKnownDead(BasicBlock *). | ||||
3315 | bool isKnownDead(const BasicBlock *BB) const override { return false; } | ||||
3316 | |||||
3317 | /// See AAIsDead::isAssumedDead(Instruction *I). | ||||
3318 | bool isAssumedDead(const Instruction *I) const override { | ||||
3319 | return I == getCtxI() && isAssumedDead(); | ||||
3320 | } | ||||
3321 | |||||
3322 | /// See AAIsDead::isKnownDead(Instruction *I). | ||||
3323 | bool isKnownDead(const Instruction *I) const override { | ||||
3324 | return isAssumedDead(I) && isKnownDead(); | ||||
3325 | } | ||||
3326 | |||||
3327 | /// See AbstractAttribute::getAsStr(). | ||||
3328 | const std::string getAsStr() const override { | ||||
3329 | return isAssumedDead() ? "assumed-dead" : "assumed-live"; | ||||
3330 | } | ||||
3331 | |||||
3332 | /// Check if all uses are assumed dead. | ||||
3333 | bool areAllUsesAssumedDead(Attributor &A, Value &V) { | ||||
3334 | // Callers might not check the type, void has no uses. | ||||
3335 | if (V.getType()->isVoidTy()) | ||||
3336 | return true; | ||||
3337 | |||||
3338 | // If we replace a value with a constant there are no uses left afterwards. | ||||
3339 | if (!isa<Constant>(V)) { | ||||
3340 | bool UsedAssumedInformation = false; | ||||
3341 | Optional<Constant *> C = | ||||
3342 | A.getAssumedConstant(V, *this, UsedAssumedInformation); | ||||
3343 | if (!C.hasValue() || *C) | ||||
3344 | return true; | ||||
3345 | } | ||||
3346 | |||||
3347 | auto UsePred = [&](const Use &U, bool &Follow) { return false; }; | ||||
3348 | // Explicitly set the dependence class to required because we want a long | ||||
3349 | // chain of N dependent instructions to be considered live as soon as one is | ||||
3350 | // without going through N update cycles. This is not required for | ||||
3351 | // correctness. | ||||
3352 | return A.checkForAllUses(UsePred, *this, V, /* CheckBBLivenessOnly */ false, | ||||
3353 | DepClassTy::REQUIRED); | ||||
3354 | } | ||||
3355 | |||||
3356 | /// Determine if \p I is assumed to be side-effect free. | ||||
3357 | bool isAssumedSideEffectFree(Attributor &A, Instruction *I) { | ||||
3358 | if (!I || wouldInstructionBeTriviallyDead(I)) | ||||
3359 | return true; | ||||
3360 | |||||
3361 | auto *CB = dyn_cast<CallBase>(I); | ||||
3362 | if (!CB || isa<IntrinsicInst>(CB)) | ||||
3363 | return false; | ||||
3364 | |||||
3365 | const IRPosition &CallIRP = IRPosition::callsite_function(*CB); | ||||
3366 | const auto &NoUnwindAA = | ||||
3367 | A.getAndUpdateAAFor<AANoUnwind>(*this, CallIRP, DepClassTy::NONE); | ||||
3368 | if (!NoUnwindAA.isAssumedNoUnwind()) | ||||
3369 | return false; | ||||
3370 | if (!NoUnwindAA.isKnownNoUnwind()) | ||||
3371 | A.recordDependence(NoUnwindAA, *this, DepClassTy::OPTIONAL); | ||||
3372 | |||||
3373 | const auto &MemBehaviorAA = | ||||
3374 | A.getAndUpdateAAFor<AAMemoryBehavior>(*this, CallIRP, DepClassTy::NONE); | ||||
3375 | if (MemBehaviorAA.isAssumedReadOnly()) { | ||||
3376 | if (!MemBehaviorAA.isKnownReadOnly()) | ||||
3377 | A.recordDependence(MemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||
3378 | return true; | ||||
3379 | } | ||||
3380 | return false; | ||||
3381 | } | ||||
3382 | }; | ||||
3383 | |||||
3384 | struct AAIsDeadFloating : public AAIsDeadValueImpl { | ||||
3385 | AAIsDeadFloating(const IRPosition &IRP, Attributor &A) | ||||
3386 | : AAIsDeadValueImpl(IRP, A) {} | ||||
3387 | |||||
3388 | /// See AbstractAttribute::initialize(...). | ||||
3389 | void initialize(Attributor &A) override { | ||||
3390 | if (isa<UndefValue>(getAssociatedValue())) { | ||||
3391 | indicatePessimisticFixpoint(); | ||||
3392 | return; | ||||
3393 | } | ||||
3394 | |||||
3395 | Instruction *I = dyn_cast<Instruction>(&getAssociatedValue()); | ||||
3396 | if (!isAssumedSideEffectFree(A, I)) { | ||||
3397 | if (!isa_and_nonnull<StoreInst>(I)) | ||||
3398 | indicatePessimisticFixpoint(); | ||||
3399 | else | ||||
3400 | removeAssumedBits(HAS_NO_EFFECT); | ||||
3401 | } | ||||
3402 | } | ||||
3403 | |||||
3404 | bool isDeadStore(Attributor &A, StoreInst &SI) { | ||||
3405 | // Lang ref now states volatile store is not UB/dead, let's skip them. | ||||
3406 | if (SI.isVolatile()) | ||||
3407 | return false; | ||||
3408 | |||||
3409 | bool UsedAssumedInformation = false; | ||||
3410 | SmallSetVector<Value *, 4> PotentialCopies; | ||||
3411 | if (!AA::getPotentialCopiesOfStoredValue(A, SI, PotentialCopies, *this, | ||||
3412 | UsedAssumedInformation)) | ||||
3413 | return false; | ||||
3414 | return llvm::all_of(PotentialCopies, [&](Value *V) { | ||||
3415 | return A.isAssumedDead(IRPosition::value(*V), this, nullptr, | ||||
3416 | UsedAssumedInformation); | ||||
3417 | }); | ||||
3418 | } | ||||
3419 | |||||
3420 | /// See AbstractAttribute::updateImpl(...). | ||||
3421 | ChangeStatus updateImpl(Attributor &A) override { | ||||
3422 | Instruction *I = dyn_cast<Instruction>(&getAssociatedValue()); | ||||
3423 | if (auto *SI = dyn_cast_or_null<StoreInst>(I)) { | ||||
3424 | if (!isDeadStore(A, *SI)) | ||||
3425 | return indicatePessimisticFixpoint(); | ||||
3426 | } else { | ||||
3427 | if (!isAssumedSideEffectFree(A, I)) | ||||
3428 | return indicatePessimisticFixpoint(); | ||||
3429 | if (!areAllUsesAssumedDead(A, getAssociatedValue())) | ||||
3430 | return indicatePessimisticFixpoint(); | ||||
3431 | } | ||||
3432 | return ChangeStatus::UNCHANGED; | ||||
3433 | } | ||||
3434 | |||||
3435 | /// See AbstractAttribute::manifest(...). | ||||
3436 | ChangeStatus manifest(Attributor &A) override { | ||||
3437 | Value &V = getAssociatedValue(); | ||||
3438 | if (auto *I = dyn_cast<Instruction>(&V)) { | ||||
3439 | // If we get here we basically know the users are all dead. We check if | ||||
3440 | // isAssumedSideEffectFree returns true here again because it might not be | ||||
3441 | // the case and only the users are dead but the instruction (=call) is | ||||
3442 | // still needed. | ||||
3443 | if (isa<StoreInst>(I) || | ||||
3444 | (isAssumedSideEffectFree(A, I) && !isa<InvokeInst>(I))) { | ||||
3445 | A.deleteAfterManifest(*I); | ||||
3446 | return ChangeStatus::CHANGED; | ||||
3447 | } | ||||
3448 | } | ||||
3449 | if (V.use_empty()) | ||||
3450 | return ChangeStatus::UNCHANGED; | ||||
3451 | |||||
3452 | bool UsedAssumedInformation = false; | ||||
3453 | Optional<Constant *> C = | ||||
3454 | A.getAssumedConstant(V, *this, UsedAssumedInformation); | ||||
3455 | if (C.hasValue() && C.getValue()) | ||||
3456 | return ChangeStatus::UNCHANGED; | ||||
3457 | |||||
3458 | // Replace the value with undef as it is dead but keep droppable uses around | ||||
3459 | // as they provide information we don't want to give up on just yet. | ||||
3460 | UndefValue &UV = *UndefValue::get(V.getType()); | ||||
3461 | bool AnyChange = | ||||
3462 | A.changeValueAfterManifest(V, UV, /* ChangeDropppable */ false); | ||||
3463 | return AnyChange ? ChangeStatus::CHANGED : ChangeStatus::UNCHANGED; | ||||
3464 | } | ||||
3465 | |||||
3466 | /// See AbstractAttribute::trackStatistics() | ||||
3467 | void trackStatistics() const override { | ||||
3468 | STATS_DECLTRACK_FLOATING_ATTR(IsDead){ static llvm::Statistic NumIRFloating_IsDead = {"attributor" , "NumIRFloating_IsDead", ("Number of floating values known to be '" "IsDead" "'")};; ++(NumIRFloating_IsDead); } | ||||
3469 | } | ||||
3470 | }; | ||||
3471 | |||||
3472 | struct AAIsDeadArgument : public AAIsDeadFloating { | ||||
3473 | AAIsDeadArgument(const IRPosition &IRP, Attributor &A) | ||||
3474 | : AAIsDeadFloating(IRP, A) {} | ||||
3475 | |||||
3476 | /// See AbstractAttribute::initialize(...). | ||||
3477 | void initialize(Attributor &A) override { | ||||
3478 | if (!A.isFunctionIPOAmendable(*getAnchorScope())) | ||||
3479 | indicatePessimisticFixpoint(); | ||||
3480 | } | ||||
3481 | |||||
3482 | /// See AbstractAttribute::manifest(...). | ||||
3483 | ChangeStatus manifest(Attributor &A) override { | ||||
3484 | ChangeStatus Changed = AAIsDeadFloating::manifest(A); | ||||
3485 | Argument &Arg = *getAssociatedArgument(); | ||||
3486 | if (A.isValidFunctionSignatureRewrite(Arg, /* ReplacementTypes */ {})) | ||||
3487 | if (A.registerFunctionSignatureRewrite( | ||||
3488 | Arg, /* ReplacementTypes */ {}, | ||||
3489 | Attributor::ArgumentReplacementInfo::CalleeRepairCBTy{}, | ||||
3490 | Attributor::ArgumentReplacementInfo::ACSRepairCBTy{})) { | ||||
3491 | Arg.dropDroppableUses(); | ||||
3492 | return ChangeStatus::CHANGED; | ||||
3493 | } | ||||
3494 | return Changed; | ||||
3495 | } | ||||
3496 | |||||
3497 | /// See AbstractAttribute::trackStatistics() | ||||
3498 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(IsDead){ static llvm::Statistic NumIRArguments_IsDead = {"attributor" , "NumIRArguments_IsDead", ("Number of " "arguments" " marked '" "IsDead" "'")};; ++(NumIRArguments_IsDead); } } | ||||
3499 | }; | ||||
3500 | |||||
3501 | struct AAIsDeadCallSiteArgument : public AAIsDeadValueImpl { | ||||
3502 | AAIsDeadCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
3503 | : AAIsDeadValueImpl(IRP, A) {} | ||||
3504 | |||||
3505 | /// See AbstractAttribute::initialize(...). | ||||
3506 | void initialize(Attributor &A) override { | ||||
3507 | if (isa<UndefValue>(getAssociatedValue())) | ||||
3508 | indicatePessimisticFixpoint(); | ||||
3509 | } | ||||
3510 | |||||
3511 | /// See AbstractAttribute::updateImpl(...). | ||||
3512 | ChangeStatus updateImpl(Attributor &A) override { | ||||
3513 | // TODO: Once we have call site specific value information we can provide | ||||
3514 | // call site specific liveness information and then it makes | ||||
3515 | // sense to specialize attributes for call sites arguments instead of | ||||
3516 | // redirecting requests to the callee argument. | ||||
3517 | Argument *Arg = getAssociatedArgument(); | ||||
3518 | if (!Arg) | ||||
3519 | return indicatePessimisticFixpoint(); | ||||
3520 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||
3521 | auto &ArgAA = A.getAAFor<AAIsDead>(*this, ArgPos, DepClassTy::REQUIRED); | ||||
3522 | return clampStateAndIndicateChange(getState(), ArgAA.getState()); | ||||
3523 | } | ||||
3524 | |||||
3525 | /// See AbstractAttribute::manifest(...). | ||||
3526 | ChangeStatus manifest(Attributor &A) override { | ||||
3527 | CallBase &CB = cast<CallBase>(getAnchorValue()); | ||||
3528 | Use &U = CB.getArgOperandUse(getCallSiteArgNo()); | ||||
3529 | assert(!isa<UndefValue>(U.get()) &&(static_cast<void> (0)) | ||||
3530 | "Expected undef values to be filtered out!")(static_cast<void> (0)); | ||||
3531 | UndefValue &UV = *UndefValue::get(U->getType()); | ||||
3532 | if (A.changeUseAfterManifest(U, UV)) | ||||
3533 | return ChangeStatus::CHANGED; | ||||
3534 | return ChangeStatus::UNCHANGED; | ||||
3535 | } | ||||
3536 | |||||
3537 | /// See AbstractAttribute::trackStatistics() | ||||
3538 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(IsDead){ static llvm::Statistic NumIRCSArguments_IsDead = {"attributor" , "NumIRCSArguments_IsDead", ("Number of " "call site arguments" " marked '" "IsDead" "'")};; ++(NumIRCSArguments_IsDead); } } | ||||
3539 | }; | ||||
3540 | |||||
3541 | struct AAIsDeadCallSiteReturned : public AAIsDeadFloating { | ||||
3542 | AAIsDeadCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
3543 | : AAIsDeadFloating(IRP, A), IsAssumedSideEffectFree(true) {} | ||||
3544 | |||||
3545 | /// See AAIsDead::isAssumedDead(). | ||||
3546 | bool isAssumedDead() const override { | ||||
3547 | return AAIsDeadFloating::isAssumedDead() && IsAssumedSideEffectFree; | ||||
3548 | } | ||||
3549 | |||||
3550 | /// See AbstractAttribute::initialize(...). | ||||
3551 | void initialize(Attributor &A) override { | ||||
3552 | if (isa<UndefValue>(getAssociatedValue())) { | ||||
3553 | indicatePessimisticFixpoint(); | ||||
3554 | return; | ||||
3555 | } | ||||
3556 | |||||
3557 | // We track this separately as a secondary state. | ||||
3558 | IsAssumedSideEffectFree = isAssumedSideEffectFree(A, getCtxI()); | ||||
3559 | } | ||||
3560 | |||||
3561 | /// See AbstractAttribute::updateImpl(...). | ||||
3562 | ChangeStatus updateImpl(Attributor &A) override { | ||||
3563 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
3564 | if (IsAssumedSideEffectFree && !isAssumedSideEffectFree(A, getCtxI())) { | ||||
3565 | IsAssumedSideEffectFree = false; | ||||
3566 | Changed = ChangeStatus::CHANGED; | ||||
3567 | } | ||||
3568 | if (!areAllUsesAssumedDead(A, getAssociatedValue())) | ||||
3569 | return indicatePessimisticFixpoint(); | ||||
3570 | return Changed; | ||||
3571 | } | ||||
3572 | |||||
3573 | /// See AbstractAttribute::trackStatistics() | ||||
3574 | void trackStatistics() const override { | ||||
3575 | if (IsAssumedSideEffectFree) | ||||
3576 | STATS_DECLTRACK_CSRET_ATTR(IsDead){ static llvm::Statistic NumIRCSReturn_IsDead = {"attributor" , "NumIRCSReturn_IsDead", ("Number of " "call site returns" " marked '" "IsDead" "'")};; ++(NumIRCSReturn_IsDead); } | ||||
3577 | else | ||||
3578 | STATS_DECLTRACK_CSRET_ATTR(UnusedResult){ static llvm::Statistic NumIRCSReturn_UnusedResult = {"attributor" , "NumIRCSReturn_UnusedResult", ("Number of " "call site returns" " marked '" "UnusedResult" "'")};; ++(NumIRCSReturn_UnusedResult ); } | ||||
3579 | } | ||||
3580 | |||||
3581 | /// See AbstractAttribute::getAsStr(). | ||||
3582 | const std::string getAsStr() const override { | ||||
3583 | return isAssumedDead() | ||||
3584 | ? "assumed-dead" | ||||
3585 | : (getAssumed() ? "assumed-dead-users" : "assumed-live"); | ||||
3586 | } | ||||
3587 | |||||
3588 | private: | ||||
3589 | bool IsAssumedSideEffectFree; | ||||
3590 | }; | ||||
3591 | |||||
3592 | struct AAIsDeadReturned : public AAIsDeadValueImpl { | ||||
3593 | AAIsDeadReturned(const IRPosition &IRP, Attributor &A) | ||||
3594 | : AAIsDeadValueImpl(IRP, A) {} | ||||
3595 | |||||
3596 | /// See AbstractAttribute::updateImpl(...). | ||||
3597 | ChangeStatus updateImpl(Attributor &A) override { | ||||
3598 | |||||
3599 | bool UsedAssumedInformation = false; | ||||
3600 | A.checkForAllInstructions([](Instruction &) { return true; }, *this, | ||||
3601 | {Instruction::Ret}, UsedAssumedInformation); | ||||
3602 | |||||
3603 | auto PredForCallSite = [&](AbstractCallSite ACS) { | ||||
3604 | if (ACS.isCallbackCall() || !ACS.getInstruction()) | ||||
3605 | return false; | ||||
3606 | return areAllUsesAssumedDead(A, *ACS.getInstruction()); | ||||
3607 | }; | ||||
3608 | |||||
3609 | bool AllCallSitesKnown; | ||||
3610 | if (!A.checkForAllCallSites(PredForCallSite, *this, true, | ||||
3611 | AllCallSitesKnown)) | ||||
3612 | return indicatePessimisticFixpoint(); | ||||
3613 | |||||
3614 | return ChangeStatus::UNCHANGED; | ||||
3615 | } | ||||
3616 | |||||
3617 | /// See AbstractAttribute::manifest(...). | ||||
3618 | ChangeStatus manifest(Attributor &A) override { | ||||
3619 | // TODO: Rewrite the signature to return void? | ||||
3620 | bool AnyChange = false; | ||||
3621 | UndefValue &UV = *UndefValue::get(getAssociatedFunction()->getReturnType()); | ||||
3622 | auto RetInstPred = [&](Instruction &I) { | ||||
3623 | ReturnInst &RI = cast<ReturnInst>(I); | ||||
3624 | if (!isa<UndefValue>(RI.getReturnValue())) | ||||
3625 | AnyChange |= A.changeUseAfterManifest(RI.getOperandUse(0), UV); | ||||
3626 | return true; | ||||
3627 | }; | ||||
3628 | bool UsedAssumedInformation = false; | ||||
3629 | A.checkForAllInstructions(RetInstPred, *this, {Instruction::Ret}, | ||||
3630 | UsedAssumedInformation); | ||||
3631 | return AnyChange ? ChangeStatus::CHANGED : ChangeStatus::UNCHANGED; | ||||
3632 | } | ||||
3633 | |||||
3634 | /// See AbstractAttribute::trackStatistics() | ||||
3635 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(IsDead){ static llvm::Statistic NumIRFunctionReturn_IsDead = {"attributor" , "NumIRFunctionReturn_IsDead", ("Number of " "function returns" " marked '" "IsDead" "'")};; ++(NumIRFunctionReturn_IsDead); } } | ||||
3636 | }; | ||||
3637 | |||||
3638 | struct AAIsDeadFunction : public AAIsDead { | ||||
3639 | AAIsDeadFunction(const IRPosition &IRP, Attributor &A) : AAIsDead(IRP, A) {} | ||||
3640 | |||||
3641 | /// See AbstractAttribute::initialize(...). | ||||
3642 | void initialize(Attributor &A) override { | ||||
3643 | const Function *F = getAnchorScope(); | ||||
3644 | if (F && !F->isDeclaration()) { | ||||
3645 | // We only want to compute liveness once. If the function is not part of | ||||
3646 | // the SCC, skip it. | ||||
3647 | if (A.isRunOn(*const_cast<Function *>(F))) { | ||||
3648 | ToBeExploredFrom.insert(&F->getEntryBlock().front()); | ||||
3649 | assumeLive(A, F->getEntryBlock()); | ||||
3650 | } else { | ||||
3651 | indicatePessimisticFixpoint(); | ||||
3652 | } | ||||
3653 | } | ||||
3654 | } | ||||
3655 | |||||
3656 | /// See AbstractAttribute::getAsStr(). | ||||
3657 | const std::string getAsStr() const override { | ||||
3658 | return "Live[#BB " + std::to_string(AssumedLiveBlocks.size()) + "/" + | ||||
3659 | std::to_string(getAnchorScope()->size()) + "][#TBEP " + | ||||
3660 | std::to_string(ToBeExploredFrom.size()) + "][#KDE " + | ||||
3661 | std::to_string(KnownDeadEnds.size()) + "]"; | ||||
3662 | } | ||||
3663 | |||||
3664 | /// See AbstractAttribute::manifest(...). | ||||
3665 | ChangeStatus manifest(Attributor &A) override { | ||||
3666 | assert(getState().isValidState() &&(static_cast<void> (0)) | ||||
3667 | "Attempted to manifest an invalid state!")(static_cast<void> (0)); | ||||
3668 | |||||
3669 | ChangeStatus HasChanged = ChangeStatus::UNCHANGED; | ||||
3670 | Function &F = *getAnchorScope(); | ||||
3671 | |||||
3672 | if (AssumedLiveBlocks.empty()) { | ||||
3673 | A.deleteAfterManifest(F); | ||||
3674 | return ChangeStatus::CHANGED; | ||||
3675 | } | ||||
3676 | |||||
3677 | // Flag to determine if we can change an invoke to a call assuming the | ||||
3678 | // callee is nounwind. This is not possible if the personality of the | ||||
3679 | // function allows to catch asynchronous exceptions. | ||||
3680 | bool Invoke2CallAllowed = !mayCatchAsynchronousExceptions(F); | ||||
3681 | |||||
3682 | KnownDeadEnds.set_union(ToBeExploredFrom); | ||||
3683 | for (const Instruction *DeadEndI : KnownDeadEnds) { | ||||
3684 | auto *CB = dyn_cast<CallBase>(DeadEndI); | ||||
3685 | if (!CB) | ||||
3686 | continue; | ||||
3687 | const auto &NoReturnAA = A.getAndUpdateAAFor<AANoReturn>( | ||||
3688 | *this, IRPosition::callsite_function(*CB), DepClassTy::OPTIONAL); | ||||
3689 | bool MayReturn = !NoReturnAA.isAssumedNoReturn(); | ||||
3690 | if (MayReturn && (!Invoke2CallAllowed || !isa<InvokeInst>(CB))) | ||||
3691 | continue; | ||||
3692 | |||||
3693 | if (auto *II = dyn_cast<InvokeInst>(DeadEndI)) | ||||
3694 | A.registerInvokeWithDeadSuccessor(const_cast<InvokeInst &>(*II)); | ||||
3695 | else | ||||
3696 | A.changeToUnreachableAfterManifest( | ||||
3697 | const_cast<Instruction *>(DeadEndI->getNextNode())); | ||||
3698 | HasChanged = ChangeStatus::CHANGED; | ||||
3699 | } | ||||
3700 | |||||
3701 | STATS_DECL(AAIsDead, BasicBlock, "Number of dead basic blocks deleted.")static llvm::Statistic NumIRBasicBlock_AAIsDead = {"attributor" , "NumIRBasicBlock_AAIsDead", "Number of dead basic blocks deleted." };;; | ||||
3702 | for (BasicBlock &BB : F) | ||||
3703 | if (!AssumedLiveBlocks.count(&BB)) { | ||||
3704 | A.deleteAfterManifest(BB); | ||||
3705 | ++BUILD_STAT_NAME(AAIsDead, BasicBlock)NumIRBasicBlock_AAIsDead; | ||||
3706 | } | ||||
3707 | |||||
3708 | return HasChanged; | ||||
3709 | } | ||||
3710 | |||||
3711 | /// See AbstractAttribute::updateImpl(...). | ||||
3712 | ChangeStatus updateImpl(Attributor &A) override; | ||||
3713 | |||||
3714 | bool isEdgeDead(const BasicBlock *From, const BasicBlock *To) const override { | ||||
3715 | return !AssumedLiveEdges.count(std::make_pair(From, To)); | ||||
3716 | } | ||||
3717 | |||||
3718 | /// See AbstractAttribute::trackStatistics() | ||||
3719 | void trackStatistics() const override {} | ||||
3720 | |||||
3721 | /// Returns true if the function is assumed dead. | ||||
3722 | bool isAssumedDead() const override { return false; } | ||||
3723 | |||||
3724 | /// See AAIsDead::isKnownDead(). | ||||
3725 | bool isKnownDead() const override { return false; } | ||||
3726 | |||||
3727 | /// See AAIsDead::isAssumedDead(BasicBlock *). | ||||
3728 | bool isAssumedDead(const BasicBlock *BB) const override { | ||||
3729 | assert(BB->getParent() == getAnchorScope() &&(static_cast<void> (0)) | ||||
3730 | "BB must be in the same anchor scope function.")(static_cast<void> (0)); | ||||
3731 | |||||
3732 | if (!getAssumed()) | ||||
3733 | return false; | ||||
3734 | return !AssumedLiveBlocks.count(BB); | ||||
3735 | } | ||||
3736 | |||||
3737 | /// See AAIsDead::isKnownDead(BasicBlock *). | ||||
3738 | bool isKnownDead(const BasicBlock *BB) const override { | ||||
3739 | return getKnown() && isAssumedDead(BB); | ||||
3740 | } | ||||
3741 | |||||
3742 | /// See AAIsDead::isAssumed(Instruction *I). | ||||
3743 | bool isAssumedDead(const Instruction *I) const override { | ||||
3744 | assert(I->getParent()->getParent() == getAnchorScope() &&(static_cast<void> (0)) | ||||
3745 | "Instruction must be in the same anchor scope function.")(static_cast<void> (0)); | ||||
3746 | |||||
3747 | if (!getAssumed()) | ||||
3748 | return false; | ||||
3749 | |||||
3750 | // If it is not in AssumedLiveBlocks then it for sure dead. | ||||
3751 | // Otherwise, it can still be after noreturn call in a live block. | ||||
3752 | if (!AssumedLiveBlocks.count(I->getParent())) | ||||
3753 | return true; | ||||
3754 | |||||
3755 | // If it is not after a liveness barrier it is live. | ||||
3756 | const Instruction *PrevI = I->getPrevNode(); | ||||
3757 | while (PrevI) { | ||||
3758 | if (KnownDeadEnds.count(PrevI) || ToBeExploredFrom.count(PrevI)) | ||||
3759 | return true; | ||||
3760 | PrevI = PrevI->getPrevNode(); | ||||
3761 | } | ||||
3762 | return false; | ||||
3763 | } | ||||
3764 | |||||
3765 | /// See AAIsDead::isKnownDead(Instruction *I). | ||||
3766 | bool isKnownDead(const Instruction *I) const override { | ||||
3767 | return getKnown() && isAssumedDead(I); | ||||
3768 | } | ||||
3769 | |||||
3770 | /// Assume \p BB is (partially) live now and indicate to the Attributor \p A | ||||
3771 | /// that internal function called from \p BB should now be looked at. | ||||
3772 | bool assumeLive(Attributor &A, const BasicBlock &BB) { | ||||
3773 | if (!AssumedLiveBlocks.insert(&BB).second) | ||||
3774 | return false; | ||||
3775 | |||||
3776 | // We assume that all of BB is (probably) live now and if there are calls to | ||||
3777 | // internal functions we will assume that those are now live as well. This | ||||
3778 | // is a performance optimization for blocks with calls to a lot of internal | ||||
3779 | // functions. It can however cause dead functions to be treated as live. | ||||
3780 | for (const Instruction &I : BB) | ||||
3781 | if (const auto *CB = dyn_cast<CallBase>(&I)) | ||||
3782 | if (const Function *F = CB->getCalledFunction()) | ||||
3783 | if (F->hasLocalLinkage()) | ||||
3784 | A.markLiveInternalFunction(*F); | ||||
3785 | return true; | ||||
3786 | } | ||||
3787 | |||||
3788 | /// Collection of instructions that need to be explored again, e.g., we | ||||
3789 | /// did assume they do not transfer control to (one of their) successors. | ||||
3790 | SmallSetVector<const Instruction *, 8> ToBeExploredFrom; | ||||
3791 | |||||
3792 | /// Collection of instructions that are known to not transfer control. | ||||
3793 | SmallSetVector<const Instruction *, 8> KnownDeadEnds; | ||||
3794 | |||||
3795 | /// Collection of all assumed live edges | ||||
3796 | DenseSet<std::pair<const BasicBlock *, const BasicBlock *>> AssumedLiveEdges; | ||||
3797 | |||||
3798 | /// Collection of all assumed live BasicBlocks. | ||||
3799 | DenseSet<const BasicBlock *> AssumedLiveBlocks; | ||||
3800 | }; | ||||
3801 | |||||
3802 | static bool | ||||
3803 | identifyAliveSuccessors(Attributor &A, const CallBase &CB, | ||||
3804 | AbstractAttribute &AA, | ||||
3805 | SmallVectorImpl<const Instruction *> &AliveSuccessors) { | ||||
3806 | const IRPosition &IPos = IRPosition::callsite_function(CB); | ||||
3807 | |||||
3808 | const auto &NoReturnAA = | ||||
3809 | A.getAndUpdateAAFor<AANoReturn>(AA, IPos, DepClassTy::OPTIONAL); | ||||
3810 | if (NoReturnAA.isAssumedNoReturn()) | ||||
3811 | return !NoReturnAA.isKnownNoReturn(); | ||||
3812 | if (CB.isTerminator()) | ||||
3813 | AliveSuccessors.push_back(&CB.getSuccessor(0)->front()); | ||||
3814 | else | ||||
3815 | AliveSuccessors.push_back(CB.getNextNode()); | ||||
3816 | return false; | ||||
3817 | } | ||||
3818 | |||||
3819 | static bool | ||||
3820 | identifyAliveSuccessors(Attributor &A, const InvokeInst &II, | ||||
3821 | AbstractAttribute &AA, | ||||
3822 | SmallVectorImpl<const Instruction *> &AliveSuccessors) { | ||||
3823 | bool UsedAssumedInformation = | ||||
3824 | identifyAliveSuccessors(A, cast<CallBase>(II), AA, AliveSuccessors); | ||||
3825 | |||||
3826 | // First, determine if we can change an invoke to a call assuming the | ||||
3827 | // callee is nounwind. This is not possible if the personality of the | ||||
3828 | // function allows to catch asynchronous exceptions. | ||||
3829 | if (AAIsDeadFunction::mayCatchAsynchronousExceptions(*II.getFunction())) { | ||||
3830 | AliveSuccessors.push_back(&II.getUnwindDest()->front()); | ||||
3831 | } else { | ||||
3832 | const IRPosition &IPos = IRPosition::callsite_function(II); | ||||
3833 | const auto &AANoUnw = | ||||
3834 | A.getAndUpdateAAFor<AANoUnwind>(AA, IPos, DepClassTy::OPTIONAL); | ||||
3835 | if (AANoUnw.isAssumedNoUnwind()) { | ||||
3836 | UsedAssumedInformation |= !AANoUnw.isKnownNoUnwind(); | ||||
3837 | } else { | ||||
3838 | AliveSuccessors.push_back(&II.getUnwindDest()->front()); | ||||
3839 | } | ||||
3840 | } | ||||
3841 | return UsedAssumedInformation; | ||||
3842 | } | ||||
3843 | |||||
3844 | static bool | ||||
3845 | identifyAliveSuccessors(Attributor &A, const BranchInst &BI, | ||||
3846 | AbstractAttribute &AA, | ||||
3847 | SmallVectorImpl<const Instruction *> &AliveSuccessors) { | ||||
3848 | bool UsedAssumedInformation = false; | ||||
3849 | if (BI.getNumSuccessors() == 1) { | ||||
3850 | AliveSuccessors.push_back(&BI.getSuccessor(0)->front()); | ||||
3851 | } else { | ||||
3852 | Optional<Constant *> C = | ||||
3853 | A.getAssumedConstant(*BI.getCondition(), AA, UsedAssumedInformation); | ||||
3854 | if (!C.hasValue() || isa_and_nonnull<UndefValue>(C.getValue())) { | ||||
3855 | // No value yet, assume both edges are dead. | ||||
3856 | } else if (isa_and_nonnull<ConstantInt>(*C)) { | ||||
3857 | const BasicBlock *SuccBB = | ||||
3858 | BI.getSuccessor(1 - cast<ConstantInt>(*C)->getValue().getZExtValue()); | ||||
3859 | AliveSuccessors.push_back(&SuccBB->front()); | ||||
3860 | } else { | ||||
3861 | AliveSuccessors.push_back(&BI.getSuccessor(0)->front()); | ||||
3862 | AliveSuccessors.push_back(&BI.getSuccessor(1)->front()); | ||||
3863 | UsedAssumedInformation = false; | ||||
3864 | } | ||||
3865 | } | ||||
3866 | return UsedAssumedInformation; | ||||
3867 | } | ||||
3868 | |||||
3869 | static bool | ||||
3870 | identifyAliveSuccessors(Attributor &A, const SwitchInst &SI, | ||||
3871 | AbstractAttribute &AA, | ||||
3872 | SmallVectorImpl<const Instruction *> &AliveSuccessors) { | ||||
3873 | bool UsedAssumedInformation = false; | ||||
3874 | Optional<Constant *> C = | ||||
3875 | A.getAssumedConstant(*SI.getCondition(), AA, UsedAssumedInformation); | ||||
3876 | if (!C.hasValue() || isa_and_nonnull<UndefValue>(C.getValue())) { | ||||
3877 | // No value yet, assume all edges are dead. | ||||
3878 | } else if (isa_and_nonnull<ConstantInt>(C.getValue())) { | ||||
3879 | for (auto &CaseIt : SI.cases()) { | ||||
3880 | if (CaseIt.getCaseValue() == C.getValue()) { | ||||
3881 | AliveSuccessors.push_back(&CaseIt.getCaseSuccessor()->front()); | ||||
3882 | return UsedAssumedInformation; | ||||
3883 | } | ||||
3884 | } | ||||
3885 | AliveSuccessors.push_back(&SI.getDefaultDest()->front()); | ||||
3886 | return UsedAssumedInformation; | ||||
3887 | } else { | ||||
3888 | for (const BasicBlock *SuccBB : successors(SI.getParent())) | ||||
3889 | AliveSuccessors.push_back(&SuccBB->front()); | ||||
3890 | } | ||||
3891 | return UsedAssumedInformation; | ||||
3892 | } | ||||
3893 | |||||
3894 | ChangeStatus AAIsDeadFunction::updateImpl(Attributor &A) { | ||||
3895 | ChangeStatus Change = ChangeStatus::UNCHANGED; | ||||
3896 | |||||
3897 | LLVM_DEBUG(dbgs() << "[AAIsDead] Live [" << AssumedLiveBlocks.size() << "/"do { } while (false) | ||||
3898 | << getAnchorScope()->size() << "] BBs and "do { } while (false) | ||||
3899 | << ToBeExploredFrom.size() << " exploration points and "do { } while (false) | ||||
3900 | << KnownDeadEnds.size() << " known dead ends\n")do { } while (false); | ||||
3901 | |||||
3902 | // Copy and clear the list of instructions we need to explore from. It is | ||||
3903 | // refilled with instructions the next update has to look at. | ||||
3904 | SmallVector<const Instruction *, 8> Worklist(ToBeExploredFrom.begin(), | ||||
3905 | ToBeExploredFrom.end()); | ||||
3906 | decltype(ToBeExploredFrom) NewToBeExploredFrom; | ||||
3907 | |||||
3908 | SmallVector<const Instruction *, 8> AliveSuccessors; | ||||
3909 | while (!Worklist.empty()) { | ||||
3910 | const Instruction *I = Worklist.pop_back_val(); | ||||
3911 | LLVM_DEBUG(dbgs() << "[AAIsDead] Exploration inst: " << *I << "\n")do { } while (false); | ||||
3912 | |||||
3913 | // Fast forward for uninteresting instructions. We could look for UB here | ||||
3914 | // though. | ||||
3915 | while (!I->isTerminator() && !isa<CallBase>(I)) | ||||
3916 | I = I->getNextNode(); | ||||
3917 | |||||
3918 | AliveSuccessors.clear(); | ||||
3919 | |||||
3920 | bool UsedAssumedInformation = false; | ||||
3921 | switch (I->getOpcode()) { | ||||
3922 | // TODO: look for (assumed) UB to backwards propagate "deadness". | ||||
3923 | default: | ||||
3924 | assert(I->isTerminator() &&(static_cast<void> (0)) | ||||
3925 | "Expected non-terminators to be handled already!")(static_cast<void> (0)); | ||||
3926 | for (const BasicBlock *SuccBB : successors(I->getParent())) | ||||
3927 | AliveSuccessors.push_back(&SuccBB->front()); | ||||
3928 | break; | ||||
3929 | case Instruction::Call: | ||||
3930 | UsedAssumedInformation = identifyAliveSuccessors(A, cast<CallInst>(*I), | ||||
3931 | *this, AliveSuccessors); | ||||
3932 | break; | ||||
3933 | case Instruction::Invoke: | ||||
3934 | UsedAssumedInformation = identifyAliveSuccessors(A, cast<InvokeInst>(*I), | ||||
3935 | *this, AliveSuccessors); | ||||
3936 | break; | ||||
3937 | case Instruction::Br: | ||||
3938 | UsedAssumedInformation = identifyAliveSuccessors(A, cast<BranchInst>(*I), | ||||
3939 | *this, AliveSuccessors); | ||||
3940 | break; | ||||
3941 | case Instruction::Switch: | ||||
3942 | UsedAssumedInformation = identifyAliveSuccessors(A, cast<SwitchInst>(*I), | ||||
3943 | *this, AliveSuccessors); | ||||
3944 | break; | ||||
3945 | } | ||||
3946 | |||||
3947 | if (UsedAssumedInformation) { | ||||
3948 | NewToBeExploredFrom.insert(I); | ||||
3949 | } else if (AliveSuccessors.empty() || | ||||
3950 | (I->isTerminator() && | ||||
3951 | AliveSuccessors.size() < I->getNumSuccessors())) { | ||||
3952 | if (KnownDeadEnds.insert(I)) | ||||
3953 | Change = ChangeStatus::CHANGED; | ||||
3954 | } | ||||
3955 | |||||
3956 | LLVM_DEBUG(dbgs() << "[AAIsDead] #AliveSuccessors: "do { } while (false) | ||||
3957 | << AliveSuccessors.size() << " UsedAssumedInformation: "do { } while (false) | ||||
3958 | << UsedAssumedInformation << "\n")do { } while (false); | ||||
3959 | |||||
3960 | for (const Instruction *AliveSuccessor : AliveSuccessors) { | ||||
3961 | if (!I->isTerminator()) { | ||||
3962 | assert(AliveSuccessors.size() == 1 &&(static_cast<void> (0)) | ||||
3963 | "Non-terminator expected to have a single successor!")(static_cast<void> (0)); | ||||
3964 | Worklist.push_back(AliveSuccessor); | ||||
3965 | } else { | ||||
3966 | // record the assumed live edge | ||||
3967 | auto Edge = std::make_pair(I->getParent(), AliveSuccessor->getParent()); | ||||
3968 | if (AssumedLiveEdges.insert(Edge).second) | ||||
3969 | Change = ChangeStatus::CHANGED; | ||||
3970 | if (assumeLive(A, *AliveSuccessor->getParent())) | ||||
3971 | Worklist.push_back(AliveSuccessor); | ||||
3972 | } | ||||
3973 | } | ||||
3974 | } | ||||
3975 | |||||
3976 | // Check if the content of ToBeExploredFrom changed, ignore the order. | ||||
3977 | if (NewToBeExploredFrom.size() != ToBeExploredFrom.size() || | ||||
3978 | llvm::any_of(NewToBeExploredFrom, [&](const Instruction *I) { | ||||
3979 | return !ToBeExploredFrom.count(I); | ||||
3980 | })) { | ||||
3981 | Change = ChangeStatus::CHANGED; | ||||
3982 | ToBeExploredFrom = std::move(NewToBeExploredFrom); | ||||
3983 | } | ||||
3984 | |||||
3985 | // If we know everything is live there is no need to query for liveness. | ||||
3986 | // Instead, indicating a pessimistic fixpoint will cause the state to be | ||||
3987 | // "invalid" and all queries to be answered conservatively without lookups. | ||||
3988 | // To be in this state we have to (1) finished the exploration and (3) not | ||||
3989 | // discovered any non-trivial dead end and (2) not ruled unreachable code | ||||
3990 | // dead. | ||||
3991 | if (ToBeExploredFrom.empty() && | ||||
3992 | getAnchorScope()->size() == AssumedLiveBlocks.size() && | ||||
3993 | llvm::all_of(KnownDeadEnds, [](const Instruction *DeadEndI) { | ||||
3994 | return DeadEndI->isTerminator() && DeadEndI->getNumSuccessors() == 0; | ||||
3995 | })) | ||||
3996 | return indicatePessimisticFixpoint(); | ||||
3997 | return Change; | ||||
3998 | } | ||||
3999 | |||||
4000 | /// Liveness information for a call sites. | ||||
4001 | struct AAIsDeadCallSite final : AAIsDeadFunction { | ||||
4002 | AAIsDeadCallSite(const IRPosition &IRP, Attributor &A) | ||||
4003 | : AAIsDeadFunction(IRP, A) {} | ||||
4004 | |||||
4005 | /// See AbstractAttribute::initialize(...). | ||||
4006 | void initialize(Attributor &A) override { | ||||
4007 | // TODO: Once we have call site specific value information we can provide | ||||
4008 | // call site specific liveness information and then it makes | ||||
4009 | // sense to specialize attributes for call sites instead of | ||||
4010 | // redirecting requests to the callee. | ||||
4011 | llvm_unreachable("Abstract attributes for liveness are not "__builtin_unreachable() | ||||
4012 | "supported for call sites yet!")__builtin_unreachable(); | ||||
4013 | } | ||||
4014 | |||||
4015 | /// See AbstractAttribute::updateImpl(...). | ||||
4016 | ChangeStatus updateImpl(Attributor &A) override { | ||||
4017 | return indicatePessimisticFixpoint(); | ||||
4018 | } | ||||
4019 | |||||
4020 | /// See AbstractAttribute::trackStatistics() | ||||
4021 | void trackStatistics() const override {} | ||||
4022 | }; | ||||
4023 | |||||
4024 | /// -------------------- Dereferenceable Argument Attribute -------------------- | ||||
4025 | |||||
4026 | struct AADereferenceableImpl : AADereferenceable { | ||||
4027 | AADereferenceableImpl(const IRPosition &IRP, Attributor &A) | ||||
4028 | : AADereferenceable(IRP, A) {} | ||||
4029 | using StateType = DerefState; | ||||
4030 | |||||
4031 | /// See AbstractAttribute::initialize(...). | ||||
4032 | void initialize(Attributor &A) override { | ||||
4033 | SmallVector<Attribute, 4> Attrs; | ||||
4034 | getAttrs({Attribute::Dereferenceable, Attribute::DereferenceableOrNull}, | ||||
4035 | Attrs, /* IgnoreSubsumingPositions */ false, &A); | ||||
4036 | for (const Attribute &Attr : Attrs) | ||||
4037 | takeKnownDerefBytesMaximum(Attr.getValueAsInt()); | ||||
4038 | |||||
4039 | const IRPosition &IRP = this->getIRPosition(); | ||||
4040 | NonNullAA = &A.getAAFor<AANonNull>(*this, IRP, DepClassTy::NONE); | ||||
4041 | |||||
4042 | bool CanBeNull, CanBeFreed; | ||||
4043 | takeKnownDerefBytesMaximum( | ||||
4044 | IRP.getAssociatedValue().getPointerDereferenceableBytes( | ||||
4045 | A.getDataLayout(), CanBeNull, CanBeFreed)); | ||||
4046 | |||||
4047 | bool IsFnInterface = IRP.isFnInterfaceKind(); | ||||
4048 | Function *FnScope = IRP.getAnchorScope(); | ||||
4049 | if (IsFnInterface && (!FnScope || !A.isFunctionIPOAmendable(*FnScope))) { | ||||
4050 | indicatePessimisticFixpoint(); | ||||
4051 | return; | ||||
4052 | } | ||||
4053 | |||||
4054 | if (Instruction *CtxI = getCtxI()) | ||||
4055 | followUsesInMBEC(*this, A, getState(), *CtxI); | ||||
4056 | } | ||||
4057 | |||||
4058 | /// See AbstractAttribute::getState() | ||||
4059 | /// { | ||||
4060 | StateType &getState() override { return *this; } | ||||
4061 | const StateType &getState() const override { return *this; } | ||||
4062 | /// } | ||||
4063 | |||||
4064 | /// Helper function for collecting accessed bytes in must-be-executed-context | ||||
4065 | void addAccessedBytesForUse(Attributor &A, const Use *U, const Instruction *I, | ||||
4066 | DerefState &State) { | ||||
4067 | const Value *UseV = U->get(); | ||||
4068 | if (!UseV->getType()->isPointerTy()) | ||||
4069 | return; | ||||
4070 | |||||
4071 | Type *PtrTy = UseV->getType(); | ||||
4072 | const DataLayout &DL = A.getDataLayout(); | ||||
4073 | int64_t Offset; | ||||
4074 | if (const Value *Base = getBasePointerOfAccessPointerOperand( | ||||
4075 | I, Offset, DL, /*AllowNonInbounds*/ true)) { | ||||
4076 | if (Base == &getAssociatedValue() && | ||||
4077 | getPointerOperand(I, /* AllowVolatile */ false) == UseV) { | ||||
4078 | uint64_t Size = DL.getTypeStoreSize(PtrTy->getPointerElementType()); | ||||
4079 | State.addAccessedBytes(Offset, Size); | ||||
4080 | } | ||||
4081 | } | ||||
4082 | } | ||||
4083 | |||||
4084 | /// See followUsesInMBEC | ||||
4085 | bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I, | ||||
4086 | AADereferenceable::StateType &State) { | ||||
4087 | bool IsNonNull = false; | ||||
4088 | bool TrackUse = false; | ||||
4089 | int64_t DerefBytes = getKnownNonNullAndDerefBytesForUse( | ||||
4090 | A, *this, getAssociatedValue(), U, I, IsNonNull, TrackUse); | ||||
4091 | LLVM_DEBUG(dbgs() << "[AADereferenceable] Deref bytes: " << DerefBytesdo { } while (false) | ||||
4092 | << " for instruction " << *I << "\n")do { } while (false); | ||||
4093 | |||||
4094 | addAccessedBytesForUse(A, U, I, State); | ||||
4095 | State.takeKnownDerefBytesMaximum(DerefBytes); | ||||
4096 | return TrackUse; | ||||
4097 | } | ||||
4098 | |||||
4099 | /// See AbstractAttribute::manifest(...). | ||||
4100 | ChangeStatus manifest(Attributor &A) override { | ||||
4101 | ChangeStatus Change = AADereferenceable::manifest(A); | ||||
4102 | if (isAssumedNonNull() && hasAttr(Attribute::DereferenceableOrNull)) { | ||||
4103 | removeAttrs({Attribute::DereferenceableOrNull}); | ||||
4104 | return ChangeStatus::CHANGED; | ||||
4105 | } | ||||
4106 | return Change; | ||||
4107 | } | ||||
4108 | |||||
4109 | void getDeducedAttributes(LLVMContext &Ctx, | ||||
4110 | SmallVectorImpl<Attribute> &Attrs) const override { | ||||
4111 | // TODO: Add *_globally support | ||||
4112 | if (isAssumedNonNull()) | ||||
4113 | Attrs.emplace_back(Attribute::getWithDereferenceableBytes( | ||||
4114 | Ctx, getAssumedDereferenceableBytes())); | ||||
4115 | else | ||||
4116 | Attrs.emplace_back(Attribute::getWithDereferenceableOrNullBytes( | ||||
4117 | Ctx, getAssumedDereferenceableBytes())); | ||||
4118 | } | ||||
4119 | |||||
4120 | /// See AbstractAttribute::getAsStr(). | ||||
4121 | const std::string getAsStr() const override { | ||||
4122 | if (!getAssumedDereferenceableBytes()) | ||||
4123 | return "unknown-dereferenceable"; | ||||
4124 | return std::string("dereferenceable") + | ||||
4125 | (isAssumedNonNull() ? "" : "_or_null") + | ||||
4126 | (isAssumedGlobal() ? "_globally" : "") + "<" + | ||||
4127 | std::to_string(getKnownDereferenceableBytes()) + "-" + | ||||
4128 | std::to_string(getAssumedDereferenceableBytes()) + ">"; | ||||
4129 | } | ||||
4130 | }; | ||||
4131 | |||||
4132 | /// Dereferenceable attribute for a floating value. | ||||
4133 | struct AADereferenceableFloating : AADereferenceableImpl { | ||||
4134 | AADereferenceableFloating(const IRPosition &IRP, Attributor &A) | ||||
4135 | : AADereferenceableImpl(IRP, A) {} | ||||
4136 | |||||
4137 | /// See AbstractAttribute::updateImpl(...). | ||||
4138 | ChangeStatus updateImpl(Attributor &A) override { | ||||
4139 | const DataLayout &DL = A.getDataLayout(); | ||||
4140 | |||||
4141 | auto VisitValueCB = [&](const Value &V, const Instruction *, DerefState &T, | ||||
4142 | bool Stripped) -> bool { | ||||
4143 | unsigned IdxWidth = | ||||
4144 | DL.getIndexSizeInBits(V.getType()->getPointerAddressSpace()); | ||||
4145 | APInt Offset(IdxWidth, 0); | ||||
4146 | const Value *Base = | ||||
4147 | stripAndAccumulateMinimalOffsets(A, *this, &V, DL, Offset, false); | ||||
4148 | |||||
4149 | const auto &AA = A.getAAFor<AADereferenceable>( | ||||
4150 | *this, IRPosition::value(*Base), DepClassTy::REQUIRED); | ||||
4151 | int64_t DerefBytes = 0; | ||||
4152 | if (!Stripped && this == &AA) { | ||||
4153 | // Use IR information if we did not strip anything. | ||||
4154 | // TODO: track globally. | ||||
4155 | bool CanBeNull, CanBeFreed; | ||||
4156 | DerefBytes = | ||||
4157 | Base->getPointerDereferenceableBytes(DL, CanBeNull, CanBeFreed); | ||||
4158 | T.GlobalState.indicatePessimisticFixpoint(); | ||||
4159 | } else { | ||||
4160 | const DerefState &DS = AA.getState(); | ||||
4161 | DerefBytes = DS.DerefBytesState.getAssumed(); | ||||
4162 | T.GlobalState &= DS.GlobalState; | ||||
4163 | } | ||||
4164 | |||||
4165 | // For now we do not try to "increase" dereferenceability due to negative | ||||
4166 | // indices as we first have to come up with code to deal with loops and | ||||
4167 | // for overflows of the dereferenceable bytes. | ||||
4168 | int64_t OffsetSExt = Offset.getSExtValue(); | ||||
4169 | if (OffsetSExt < 0) | ||||
4170 | OffsetSExt = 0; | ||||
4171 | |||||
4172 | T.takeAssumedDerefBytesMinimum( | ||||
4173 | std::max(int64_t(0), DerefBytes - OffsetSExt)); | ||||
4174 | |||||
4175 | if (this == &AA) { | ||||
4176 | if (!Stripped) { | ||||
4177 | // If nothing was stripped IR information is all we got. | ||||
4178 | T.takeKnownDerefBytesMaximum( | ||||
4179 | std::max(int64_t(0), DerefBytes - OffsetSExt)); | ||||
4180 | T.indicatePessimisticFixpoint(); | ||||
4181 | } else if (OffsetSExt > 0) { | ||||
4182 | // If something was stripped but there is circular reasoning we look | ||||
4183 | // for the offset. If it is positive we basically decrease the | ||||
4184 | // dereferenceable bytes in a circluar loop now, which will simply | ||||
4185 | // drive them down to the known value in a very slow way which we | ||||
4186 | // can accelerate. | ||||
4187 | T.indicatePessimisticFixpoint(); | ||||
4188 | } | ||||
4189 | } | ||||
4190 | |||||
4191 | return T.isValidState(); | ||||
4192 | }; | ||||
4193 | |||||
4194 | DerefState T; | ||||
4195 | if (!genericValueTraversal<DerefState>(A, getIRPosition(), *this, T, | ||||
4196 | VisitValueCB, getCtxI())) | ||||
4197 | return indicatePessimisticFixpoint(); | ||||
4198 | |||||
4199 | return clampStateAndIndicateChange(getState(), T); | ||||
4200 | } | ||||
4201 | |||||
4202 | /// See AbstractAttribute::trackStatistics() | ||||
4203 | void trackStatistics() const override { | ||||
4204 | STATS_DECLTRACK_FLOATING_ATTR(dereferenceable){ static llvm::Statistic NumIRFloating_dereferenceable = {"attributor" , "NumIRFloating_dereferenceable", ("Number of floating values known to be '" "dereferenceable" "'")};; ++(NumIRFloating_dereferenceable); } | ||||
4205 | } | ||||
4206 | }; | ||||
4207 | |||||
4208 | /// Dereferenceable attribute for a return value. | ||||
4209 | struct AADereferenceableReturned final | ||||
4210 | : AAReturnedFromReturnedValues<AADereferenceable, AADereferenceableImpl> { | ||||
4211 | AADereferenceableReturned(const IRPosition &IRP, Attributor &A) | ||||
4212 | : AAReturnedFromReturnedValues<AADereferenceable, AADereferenceableImpl>( | ||||
4213 | IRP, A) {} | ||||
4214 | |||||
4215 | /// See AbstractAttribute::trackStatistics() | ||||
4216 | void trackStatistics() const override { | ||||
4217 | STATS_DECLTRACK_FNRET_ATTR(dereferenceable){ static llvm::Statistic NumIRFunctionReturn_dereferenceable = {"attributor", "NumIRFunctionReturn_dereferenceable", ("Number of " "function returns" " marked '" "dereferenceable" "'")};; ++( NumIRFunctionReturn_dereferenceable); } | ||||
4218 | } | ||||
4219 | }; | ||||
4220 | |||||
4221 | /// Dereferenceable attribute for an argument | ||||
4222 | struct AADereferenceableArgument final | ||||
4223 | : AAArgumentFromCallSiteArguments<AADereferenceable, | ||||
4224 | AADereferenceableImpl> { | ||||
4225 | using Base = | ||||
4226 | AAArgumentFromCallSiteArguments<AADereferenceable, AADereferenceableImpl>; | ||||
4227 | AADereferenceableArgument(const IRPosition &IRP, Attributor &A) | ||||
4228 | : Base(IRP, A) {} | ||||
4229 | |||||
4230 | /// See AbstractAttribute::trackStatistics() | ||||
4231 | void trackStatistics() const override { | ||||
4232 | STATS_DECLTRACK_ARG_ATTR(dereferenceable){ static llvm::Statistic NumIRArguments_dereferenceable = {"attributor" , "NumIRArguments_dereferenceable", ("Number of " "arguments" " marked '" "dereferenceable" "'")};; ++(NumIRArguments_dereferenceable ); } | ||||
4233 | } | ||||
4234 | }; | ||||
4235 | |||||
4236 | /// Dereferenceable attribute for a call site argument. | ||||
4237 | struct AADereferenceableCallSiteArgument final : AADereferenceableFloating { | ||||
4238 | AADereferenceableCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
4239 | : AADereferenceableFloating(IRP, A) {} | ||||
4240 | |||||
4241 | /// See AbstractAttribute::trackStatistics() | ||||
4242 | void trackStatistics() const override { | ||||
4243 | STATS_DECLTRACK_CSARG_ATTR(dereferenceable){ static llvm::Statistic NumIRCSArguments_dereferenceable = { "attributor", "NumIRCSArguments_dereferenceable", ("Number of " "call site arguments" " marked '" "dereferenceable" "'")};; ++ (NumIRCSArguments_dereferenceable); } | ||||
4244 | } | ||||
4245 | }; | ||||
4246 | |||||
4247 | /// Dereferenceable attribute deduction for a call site return value. | ||||
4248 | struct AADereferenceableCallSiteReturned final | ||||
4249 | : AACallSiteReturnedFromReturned<AADereferenceable, AADereferenceableImpl> { | ||||
4250 | using Base = | ||||
4251 | AACallSiteReturnedFromReturned<AADereferenceable, AADereferenceableImpl>; | ||||
4252 | AADereferenceableCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
4253 | : Base(IRP, A) {} | ||||
4254 | |||||
4255 | /// See AbstractAttribute::trackStatistics() | ||||
4256 | void trackStatistics() const override { | ||||
4257 | STATS_DECLTRACK_CS_ATTR(dereferenceable){ static llvm::Statistic NumIRCS_dereferenceable = {"attributor" , "NumIRCS_dereferenceable", ("Number of " "call site" " marked '" "dereferenceable" "'")};; ++(NumIRCS_dereferenceable); }; | ||||
4258 | } | ||||
4259 | }; | ||||
4260 | |||||
4261 | // ------------------------ Align Argument Attribute ------------------------ | ||||
4262 | |||||
4263 | static unsigned getKnownAlignForUse(Attributor &A, AAAlign &QueryingAA, | ||||
4264 | Value &AssociatedValue, const Use *U, | ||||
4265 | const Instruction *I, bool &TrackUse) { | ||||
4266 | // We need to follow common pointer manipulation uses to the accesses they | ||||
4267 | // feed into. | ||||
4268 | if (isa<CastInst>(I)) { | ||||
4269 | // Follow all but ptr2int casts. | ||||
4270 | TrackUse = !isa<PtrToIntInst>(I); | ||||
4271 | return 0; | ||||
4272 | } | ||||
4273 | if (auto *GEP = dyn_cast<GetElementPtrInst>(I)) { | ||||
4274 | if (GEP->hasAllConstantIndices()) | ||||
4275 | TrackUse = true; | ||||
4276 | return 0; | ||||
4277 | } | ||||
4278 | |||||
4279 | MaybeAlign MA; | ||||
4280 | if (const auto *CB = dyn_cast<CallBase>(I)) { | ||||
4281 | if (CB->isBundleOperand(U) || CB->isCallee(U)) | ||||
4282 | return 0; | ||||
4283 | |||||
4284 | unsigned ArgNo = CB->getArgOperandNo(U); | ||||
4285 | IRPosition IRP = IRPosition::callsite_argument(*CB, ArgNo); | ||||
4286 | // As long as we only use known information there is no need to track | ||||
4287 | // dependences here. | ||||
4288 | auto &AlignAA = A.getAAFor<AAAlign>(QueryingAA, IRP, DepClassTy::NONE); | ||||
4289 | MA = MaybeAlign(AlignAA.getKnownAlign()); | ||||
4290 | } | ||||
4291 | |||||
4292 | const DataLayout &DL = A.getDataLayout(); | ||||
4293 | const Value *UseV = U->get(); | ||||
4294 | if (auto *SI = dyn_cast<StoreInst>(I)) { | ||||
4295 | if (SI->getPointerOperand() == UseV) | ||||
4296 | MA = SI->getAlign(); | ||||
4297 | } else if (auto *LI = dyn_cast<LoadInst>(I)) { | ||||
4298 | if (LI->getPointerOperand() == UseV) | ||||
4299 | MA = LI->getAlign(); | ||||
4300 | } | ||||
4301 | |||||
4302 | if (!MA || *MA <= QueryingAA.getKnownAlign()) | ||||
4303 | return 0; | ||||
4304 | |||||
4305 | unsigned Alignment = MA->value(); | ||||
4306 | int64_t Offset; | ||||
4307 | |||||
4308 | if (const Value *Base = GetPointerBaseWithConstantOffset(UseV, Offset, DL)) { | ||||
4309 | if (Base == &AssociatedValue) { | ||||
4310 | // BasePointerAddr + Offset = Alignment * Q for some integer Q. | ||||
4311 | // So we can say that the maximum power of two which is a divisor of | ||||
4312 | // gcd(Offset, Alignment) is an alignment. | ||||
4313 | |||||
4314 | uint32_t gcd = | ||||
4315 | greatestCommonDivisor(uint32_t(abs((int32_t)Offset)), Alignment); | ||||
4316 | Alignment = llvm::PowerOf2Floor(gcd); | ||||
4317 | } | ||||
4318 | } | ||||
4319 | |||||
4320 | return Alignment; | ||||
4321 | } | ||||
4322 | |||||
4323 | struct AAAlignImpl : AAAlign { | ||||
4324 | AAAlignImpl(const IRPosition &IRP, Attributor &A) : AAAlign(IRP, A) {} | ||||
4325 | |||||
4326 | /// See AbstractAttribute::initialize(...). | ||||
4327 | void initialize(Attributor &A) override { | ||||
4328 | SmallVector<Attribute, 4> Attrs; | ||||
4329 | getAttrs({Attribute::Alignment}, Attrs); | ||||
4330 | for (const Attribute &Attr : Attrs) | ||||
4331 | takeKnownMaximum(Attr.getValueAsInt()); | ||||
4332 | |||||
4333 | Value &V = getAssociatedValue(); | ||||
4334 | // TODO: This is a HACK to avoid getPointerAlignment to introduce a ptr2int | ||||
4335 | // use of the function pointer. This was caused by D73131. We want to | ||||
4336 | // avoid this for function pointers especially because we iterate | ||||
4337 | // their uses and int2ptr is not handled. It is not a correctness | ||||
4338 | // problem though! | ||||
4339 | if (!V.getType()->getPointerElementType()->isFunctionTy()) | ||||
4340 | takeKnownMaximum(V.getPointerAlignment(A.getDataLayout()).value()); | ||||
4341 | |||||
4342 | if (getIRPosition().isFnInterfaceKind() && | ||||
4343 | (!getAnchorScope() || | ||||
4344 | !A.isFunctionIPOAmendable(*getAssociatedFunction()))) { | ||||
4345 | indicatePessimisticFixpoint(); | ||||
4346 | return; | ||||
4347 | } | ||||
4348 | |||||
4349 | if (Instruction *CtxI = getCtxI()) | ||||
4350 | followUsesInMBEC(*this, A, getState(), *CtxI); | ||||
4351 | } | ||||
4352 | |||||
4353 | /// See AbstractAttribute::manifest(...). | ||||
4354 | ChangeStatus manifest(Attributor &A) override { | ||||
4355 | ChangeStatus LoadStoreChanged = ChangeStatus::UNCHANGED; | ||||
4356 | |||||
4357 | // Check for users that allow alignment annotations. | ||||
4358 | Value &AssociatedValue = getAssociatedValue(); | ||||
4359 | for (const Use &U : AssociatedValue.uses()) { | ||||
4360 | if (auto *SI = dyn_cast<StoreInst>(U.getUser())) { | ||||
4361 | if (SI->getPointerOperand() == &AssociatedValue) | ||||
4362 | if (SI->getAlignment() < getAssumedAlign()) { | ||||
4363 | STATS_DECLTRACK(AAAlign, Store,{ static llvm::Statistic NumIRStore_AAAlign = {"attributor", "NumIRStore_AAAlign" , "Number of times alignment added to a store"};; ++(NumIRStore_AAAlign ); } | ||||
4364 | "Number of times alignment added to a store"){ static llvm::Statistic NumIRStore_AAAlign = {"attributor", "NumIRStore_AAAlign" , "Number of times alignment added to a store"};; ++(NumIRStore_AAAlign ); }; | ||||
4365 | SI->setAlignment(Align(getAssumedAlign())); | ||||
4366 | LoadStoreChanged = ChangeStatus::CHANGED; | ||||
4367 | } | ||||
4368 | } else if (auto *LI = dyn_cast<LoadInst>(U.getUser())) { | ||||
4369 | if (LI->getPointerOperand() == &AssociatedValue) | ||||
4370 | if (LI->getAlignment() < getAssumedAlign()) { | ||||
4371 | LI->setAlignment(Align(getAssumedAlign())); | ||||
4372 | STATS_DECLTRACK(AAAlign, Load,{ static llvm::Statistic NumIRLoad_AAAlign = {"attributor", "NumIRLoad_AAAlign" , "Number of times alignment added to a load"};; ++(NumIRLoad_AAAlign ); } | ||||
4373 | "Number of times alignment added to a load"){ static llvm::Statistic NumIRLoad_AAAlign = {"attributor", "NumIRLoad_AAAlign" , "Number of times alignment added to a load"};; ++(NumIRLoad_AAAlign ); }; | ||||
4374 | LoadStoreChanged = ChangeStatus::CHANGED; | ||||
4375 | } | ||||
4376 | } | ||||
4377 | } | ||||
4378 | |||||
4379 | ChangeStatus Changed = AAAlign::manifest(A); | ||||
4380 | |||||
4381 | Align InheritAlign = | ||||
4382 | getAssociatedValue().getPointerAlignment(A.getDataLayout()); | ||||
4383 | if (InheritAlign >= getAssumedAlign()) | ||||
4384 | return LoadStoreChanged; | ||||
4385 | return Changed | LoadStoreChanged; | ||||
4386 | } | ||||
4387 | |||||
4388 | // TODO: Provide a helper to determine the implied ABI alignment and check in | ||||
4389 | // the existing manifest method and a new one for AAAlignImpl that value | ||||
4390 | // to avoid making the alignment explicit if it did not improve. | ||||
4391 | |||||
4392 | /// See AbstractAttribute::getDeducedAttributes | ||||
4393 | virtual void | ||||
4394 | getDeducedAttributes(LLVMContext &Ctx, | ||||
4395 | SmallVectorImpl<Attribute> &Attrs) const override { | ||||
4396 | if (getAssumedAlign() > 1) | ||||
4397 | Attrs.emplace_back( | ||||
4398 | Attribute::getWithAlignment(Ctx, Align(getAssumedAlign()))); | ||||
4399 | } | ||||
4400 | |||||
4401 | /// See followUsesInMBEC | ||||
4402 | bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I, | ||||
4403 | AAAlign::StateType &State) { | ||||
4404 | bool TrackUse = false; | ||||
4405 | |||||
4406 | unsigned int KnownAlign = | ||||
4407 | getKnownAlignForUse(A, *this, getAssociatedValue(), U, I, TrackUse); | ||||
4408 | State.takeKnownMaximum(KnownAlign); | ||||
4409 | |||||
4410 | return TrackUse; | ||||
4411 | } | ||||
4412 | |||||
4413 | /// See AbstractAttribute::getAsStr(). | ||||
4414 | const std::string getAsStr() const override { | ||||
4415 | return getAssumedAlign() ? ("align<" + std::to_string(getKnownAlign()) + | ||||
4416 | "-" + std::to_string(getAssumedAlign()) + ">") | ||||
4417 | : "unknown-align"; | ||||
4418 | } | ||||
4419 | }; | ||||
4420 | |||||
4421 | /// Align attribute for a floating value. | ||||
4422 | struct AAAlignFloating : AAAlignImpl { | ||||
4423 | AAAlignFloating(const IRPosition &IRP, Attributor &A) : AAAlignImpl(IRP, A) {} | ||||
4424 | |||||
4425 | /// See AbstractAttribute::updateImpl(...). | ||||
4426 | ChangeStatus updateImpl(Attributor &A) override { | ||||
4427 | const DataLayout &DL = A.getDataLayout(); | ||||
4428 | |||||
4429 | auto VisitValueCB = [&](Value &V, const Instruction *, | ||||
4430 | AAAlign::StateType &T, bool Stripped) -> bool { | ||||
4431 | const auto &AA = A.getAAFor<AAAlign>(*this, IRPosition::value(V), | ||||
4432 | DepClassTy::REQUIRED); | ||||
4433 | if (!Stripped && this == &AA) { | ||||
4434 | int64_t Offset; | ||||
4435 | unsigned Alignment = 1; | ||||
4436 | if (const Value *Base = | ||||
4437 | GetPointerBaseWithConstantOffset(&V, Offset, DL)) { | ||||
4438 | Align PA = Base->getPointerAlignment(DL); | ||||
4439 | // BasePointerAddr + Offset = Alignment * Q for some integer Q. | ||||
4440 | // So we can say that the maximum power of two which is a divisor of | ||||
4441 | // gcd(Offset, Alignment) is an alignment. | ||||
4442 | |||||
4443 | uint32_t gcd = greatestCommonDivisor(uint32_t(abs((int32_t)Offset)), | ||||
4444 | uint32_t(PA.value())); | ||||
4445 | Alignment = llvm::PowerOf2Floor(gcd); | ||||
4446 | } else { | ||||
4447 | Alignment = V.getPointerAlignment(DL).value(); | ||||
4448 | } | ||||
4449 | // Use only IR information if we did not strip anything. | ||||
4450 | T.takeKnownMaximum(Alignment); | ||||
4451 | T.indicatePessimisticFixpoint(); | ||||
4452 | } else { | ||||
4453 | // Use abstract attribute information. | ||||
4454 | const AAAlign::StateType &DS = AA.getState(); | ||||
4455 | T ^= DS; | ||||
4456 | } | ||||
4457 | return T.isValidState(); | ||||
4458 | }; | ||||
4459 | |||||
4460 | StateType T; | ||||
4461 | if (!genericValueTraversal<StateType>(A, getIRPosition(), *this, T, | ||||
4462 | VisitValueCB, getCtxI())) | ||||
4463 | return indicatePessimisticFixpoint(); | ||||
4464 | |||||
4465 | // TODO: If we know we visited all incoming values, thus no are assumed | ||||
4466 | // dead, we can take the known information from the state T. | ||||
4467 | return clampStateAndIndicateChange(getState(), T); | ||||
4468 | } | ||||
4469 | |||||
4470 | /// See AbstractAttribute::trackStatistics() | ||||
4471 | void trackStatistics() const override { STATS_DECLTRACK_FLOATING_ATTR(align){ static llvm::Statistic NumIRFloating_align = {"attributor", "NumIRFloating_align", ("Number of floating values known to be '" "align" "'")};; ++(NumIRFloating_align); } } | ||||
4472 | }; | ||||
4473 | |||||
4474 | /// Align attribute for function return value. | ||||
4475 | struct AAAlignReturned final | ||||
4476 | : AAReturnedFromReturnedValues<AAAlign, AAAlignImpl> { | ||||
4477 | using Base = AAReturnedFromReturnedValues<AAAlign, AAAlignImpl>; | ||||
4478 | AAAlignReturned(const IRPosition &IRP, Attributor &A) : Base(IRP, A) {} | ||||
4479 | |||||
4480 | /// See AbstractAttribute::initialize(...). | ||||
4481 | void initialize(Attributor &A) override { | ||||
4482 | Base::initialize(A); | ||||
4483 | Function *F = getAssociatedFunction(); | ||||
4484 | if (!F || F->isDeclaration()) | ||||
4485 | indicatePessimisticFixpoint(); | ||||
4486 | } | ||||
4487 | |||||
4488 | /// See AbstractAttribute::trackStatistics() | ||||
4489 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(aligned){ static llvm::Statistic NumIRFunctionReturn_aligned = {"attributor" , "NumIRFunctionReturn_aligned", ("Number of " "function returns" " marked '" "aligned" "'")};; ++(NumIRFunctionReturn_aligned ); } } | ||||
4490 | }; | ||||
4491 | |||||
4492 | /// Align attribute for function argument. | ||||
4493 | struct AAAlignArgument final | ||||
4494 | : AAArgumentFromCallSiteArguments<AAAlign, AAAlignImpl> { | ||||
4495 | using Base = AAArgumentFromCallSiteArguments<AAAlign, AAAlignImpl>; | ||||
4496 | AAAlignArgument(const IRPosition &IRP, Attributor &A) : Base(IRP, A) {} | ||||
4497 | |||||
4498 | /// See AbstractAttribute::manifest(...). | ||||
4499 | ChangeStatus manifest(Attributor &A) override { | ||||
4500 | // If the associated argument is involved in a must-tail call we give up | ||||
4501 | // because we would need to keep the argument alignments of caller and | ||||
4502 | // callee in-sync. Just does not seem worth the trouble right now. | ||||
4503 | if (A.getInfoCache().isInvolvedInMustTailCall(*getAssociatedArgument())) | ||||
4504 | return ChangeStatus::UNCHANGED; | ||||
4505 | return Base::manifest(A); | ||||
4506 | } | ||||
4507 | |||||
4508 | /// See AbstractAttribute::trackStatistics() | ||||
4509 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(aligned){ static llvm::Statistic NumIRArguments_aligned = {"attributor" , "NumIRArguments_aligned", ("Number of " "arguments" " marked '" "aligned" "'")};; ++(NumIRArguments_aligned); } } | ||||
4510 | }; | ||||
4511 | |||||
4512 | struct AAAlignCallSiteArgument final : AAAlignFloating { | ||||
4513 | AAAlignCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
4514 | : AAAlignFloating(IRP, A) {} | ||||
4515 | |||||
4516 | /// See AbstractAttribute::manifest(...). | ||||
4517 | ChangeStatus manifest(Attributor &A) override { | ||||
4518 | // If the associated argument is involved in a must-tail call we give up | ||||
4519 | // because we would need to keep the argument alignments of caller and | ||||
4520 | // callee in-sync. Just does not seem worth the trouble right now. | ||||
4521 | if (Argument *Arg = getAssociatedArgument()) | ||||
4522 | if (A.getInfoCache().isInvolvedInMustTailCall(*Arg)) | ||||
4523 | return ChangeStatus::UNCHANGED; | ||||
4524 | ChangeStatus Changed = AAAlignImpl::manifest(A); | ||||
4525 | Align InheritAlign = | ||||
4526 | getAssociatedValue().getPointerAlignment(A.getDataLayout()); | ||||
4527 | if (InheritAlign >= getAssumedAlign()) | ||||
4528 | Changed = ChangeStatus::UNCHANGED; | ||||
4529 | return Changed; | ||||
4530 | } | ||||
4531 | |||||
4532 | /// See AbstractAttribute::updateImpl(Attributor &A). | ||||
4533 | ChangeStatus updateImpl(Attributor &A) override { | ||||
4534 | ChangeStatus Changed = AAAlignFloating::updateImpl(A); | ||||
4535 | if (Argument *Arg = getAssociatedArgument()) { | ||||
4536 | // We only take known information from the argument | ||||
4537 | // so we do not need to track a dependence. | ||||
4538 | const auto &ArgAlignAA = A.getAAFor<AAAlign>( | ||||
4539 | *this, IRPosition::argument(*Arg), DepClassTy::NONE); | ||||
4540 | takeKnownMaximum(ArgAlignAA.getKnownAlign()); | ||||
4541 | } | ||||
4542 | return Changed; | ||||
4543 | } | ||||
4544 | |||||
4545 | /// See AbstractAttribute::trackStatistics() | ||||
4546 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(aligned){ static llvm::Statistic NumIRCSArguments_aligned = {"attributor" , "NumIRCSArguments_aligned", ("Number of " "call site arguments" " marked '" "aligned" "'")};; ++(NumIRCSArguments_aligned); } } | ||||
4547 | }; | ||||
4548 | |||||
4549 | /// Align attribute deduction for a call site return value. | ||||
4550 | struct AAAlignCallSiteReturned final | ||||
4551 | : AACallSiteReturnedFromReturned<AAAlign, AAAlignImpl> { | ||||
4552 | using Base = AACallSiteReturnedFromReturned<AAAlign, AAAlignImpl>; | ||||
4553 | AAAlignCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
4554 | : Base(IRP, A) {} | ||||
4555 | |||||
4556 | /// See AbstractAttribute::initialize(...). | ||||
4557 | void initialize(Attributor &A) override { | ||||
4558 | Base::initialize(A); | ||||
4559 | Function *F = getAssociatedFunction(); | ||||
4560 | if (!F || F->isDeclaration()) | ||||
4561 | indicatePessimisticFixpoint(); | ||||
4562 | } | ||||
4563 | |||||
4564 | /// See AbstractAttribute::trackStatistics() | ||||
4565 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(align){ static llvm::Statistic NumIRCS_align = {"attributor", "NumIRCS_align" , ("Number of " "call site" " marked '" "align" "'")};; ++(NumIRCS_align ); }; } | ||||
4566 | }; | ||||
4567 | |||||
4568 | /// ------------------ Function No-Return Attribute ---------------------------- | ||||
4569 | struct AANoReturnImpl : public AANoReturn { | ||||
4570 | AANoReturnImpl(const IRPosition &IRP, Attributor &A) : AANoReturn(IRP, A) {} | ||||
4571 | |||||
4572 | /// See AbstractAttribute::initialize(...). | ||||
4573 | void initialize(Attributor &A) override { | ||||
4574 | AANoReturn::initialize(A); | ||||
4575 | Function *F = getAssociatedFunction(); | ||||
4576 | if (!F || F->isDeclaration()) | ||||
4577 | indicatePessimisticFixpoint(); | ||||
4578 | } | ||||
4579 | |||||
4580 | /// See AbstractAttribute::getAsStr(). | ||||
4581 | const std::string getAsStr() const override { | ||||
4582 | return getAssumed() ? "noreturn" : "may-return"; | ||||
4583 | } | ||||
4584 | |||||
4585 | /// See AbstractAttribute::updateImpl(Attributor &A). | ||||
4586 | virtual ChangeStatus updateImpl(Attributor &A) override { | ||||
4587 | auto CheckForNoReturn = [](Instruction &) { return false; }; | ||||
4588 | bool UsedAssumedInformation = false; | ||||
4589 | if (!A.checkForAllInstructions(CheckForNoReturn, *this, | ||||
4590 | {(unsigned)Instruction::Ret}, | ||||
4591 | UsedAssumedInformation)) | ||||
4592 | return indicatePessimisticFixpoint(); | ||||
4593 | return ChangeStatus::UNCHANGED; | ||||
4594 | } | ||||
4595 | }; | ||||
4596 | |||||
4597 | struct AANoReturnFunction final : AANoReturnImpl { | ||||
4598 | AANoReturnFunction(const IRPosition &IRP, Attributor &A) | ||||
4599 | : AANoReturnImpl(IRP, A) {} | ||||
4600 | |||||
4601 | /// See AbstractAttribute::trackStatistics() | ||||
4602 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(noreturn){ static llvm::Statistic NumIRFunction_noreturn = {"attributor" , "NumIRFunction_noreturn", ("Number of " "functions" " marked '" "noreturn" "'")};; ++(NumIRFunction_noreturn); } } | ||||
4603 | }; | ||||
4604 | |||||
4605 | /// NoReturn attribute deduction for a call sites. | ||||
4606 | struct AANoReturnCallSite final : AANoReturnImpl { | ||||
4607 | AANoReturnCallSite(const IRPosition &IRP, Attributor &A) | ||||
4608 | : AANoReturnImpl(IRP, A) {} | ||||
4609 | |||||
4610 | /// See AbstractAttribute::initialize(...). | ||||
4611 | void initialize(Attributor &A) override { | ||||
4612 | AANoReturnImpl::initialize(A); | ||||
4613 | if (Function *F = getAssociatedFunction()) { | ||||
4614 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
4615 | auto &FnAA = A.getAAFor<AANoReturn>(*this, FnPos, DepClassTy::REQUIRED); | ||||
4616 | if (!FnAA.isAssumedNoReturn()) | ||||
4617 | indicatePessimisticFixpoint(); | ||||
4618 | } | ||||
4619 | } | ||||
4620 | |||||
4621 | /// See AbstractAttribute::updateImpl(...). | ||||
4622 | ChangeStatus updateImpl(Attributor &A) override { | ||||
4623 | // TODO: Once we have call site specific value information we can provide | ||||
4624 | // call site specific liveness information and then it makes | ||||
4625 | // sense to specialize attributes for call sites arguments instead of | ||||
4626 | // redirecting requests to the callee argument. | ||||
4627 | Function *F = getAssociatedFunction(); | ||||
4628 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
4629 | auto &FnAA = A.getAAFor<AANoReturn>(*this, FnPos, DepClassTy::REQUIRED); | ||||
4630 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||
4631 | } | ||||
4632 | |||||
4633 | /// See AbstractAttribute::trackStatistics() | ||||
4634 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(noreturn){ static llvm::Statistic NumIRCS_noreturn = {"attributor", "NumIRCS_noreturn" , ("Number of " "call site" " marked '" "noreturn" "'")};; ++ (NumIRCS_noreturn); }; } | ||||
4635 | }; | ||||
4636 | |||||
4637 | /// ----------------------- Variable Capturing --------------------------------- | ||||
4638 | |||||
4639 | /// A class to hold the state of for no-capture attributes. | ||||
4640 | struct AANoCaptureImpl : public AANoCapture { | ||||
4641 | AANoCaptureImpl(const IRPosition &IRP, Attributor &A) : AANoCapture(IRP, A) {} | ||||
4642 | |||||
4643 | /// See AbstractAttribute::initialize(...). | ||||
4644 | void initialize(Attributor &A) override { | ||||
4645 | if (hasAttr(getAttrKind(), /* IgnoreSubsumingPositions */ true)) { | ||||
4646 | indicateOptimisticFixpoint(); | ||||
4647 | return; | ||||
4648 | } | ||||
4649 | Function *AnchorScope = getAnchorScope(); | ||||
4650 | if (isFnInterfaceKind() && | ||||
4651 | (!AnchorScope || !A.isFunctionIPOAmendable(*AnchorScope))) { | ||||
4652 | indicatePessimisticFixpoint(); | ||||
4653 | return; | ||||
4654 | } | ||||
4655 | |||||
4656 | // You cannot "capture" null in the default address space. | ||||
4657 | if (isa<ConstantPointerNull>(getAssociatedValue()) && | ||||
4658 | getAssociatedValue().getType()->getPointerAddressSpace() == 0) { | ||||
4659 | indicateOptimisticFixpoint(); | ||||
4660 | return; | ||||
4661 | } | ||||
4662 | |||||
4663 | const Function *F = | ||||
4664 | isArgumentPosition() ? getAssociatedFunction() : AnchorScope; | ||||
4665 | |||||
4666 | // Check what state the associated function can actually capture. | ||||
4667 | if (F) | ||||
4668 | determineFunctionCaptureCapabilities(getIRPosition(), *F, *this); | ||||
4669 | else | ||||
4670 | indicatePessimisticFixpoint(); | ||||
4671 | } | ||||
4672 | |||||
4673 | /// See AbstractAttribute::updateImpl(...). | ||||
4674 | ChangeStatus updateImpl(Attributor &A) override; | ||||
4675 | |||||
4676 | /// see AbstractAttribute::isAssumedNoCaptureMaybeReturned(...). | ||||
4677 | virtual void | ||||
4678 | getDeducedAttributes(LLVMContext &Ctx, | ||||
4679 | SmallVectorImpl<Attribute> &Attrs) const override { | ||||
4680 | if (!isAssumedNoCaptureMaybeReturned()) | ||||
4681 | return; | ||||
4682 | |||||
4683 | if (isArgumentPosition()) { | ||||
4684 | if (isAssumedNoCapture()) | ||||
4685 | Attrs.emplace_back(Attribute::get(Ctx, Attribute::NoCapture)); | ||||
4686 | else if (ManifestInternal) | ||||
4687 | Attrs.emplace_back(Attribute::get(Ctx, "no-capture-maybe-returned")); | ||||
4688 | } | ||||
4689 | } | ||||
4690 | |||||
4691 | /// Set the NOT_CAPTURED_IN_MEM and NOT_CAPTURED_IN_RET bits in \p Known | ||||
4692 | /// depending on the ability of the function associated with \p IRP to capture | ||||
4693 | /// state in memory and through "returning/throwing", respectively. | ||||
4694 | static void determineFunctionCaptureCapabilities(const IRPosition &IRP, | ||||
4695 | const Function &F, | ||||
4696 | BitIntegerState &State) { | ||||
4697 | // TODO: Once we have memory behavior attributes we should use them here. | ||||
4698 | |||||
4699 | // If we know we cannot communicate or write to memory, we do not care about | ||||
4700 | // ptr2int anymore. | ||||
4701 | if (F.onlyReadsMemory() && F.doesNotThrow() && | ||||
4702 | F.getReturnType()->isVoidTy()) { | ||||
4703 | State.addKnownBits(NO_CAPTURE); | ||||
4704 | return; | ||||
4705 | } | ||||
4706 | |||||
4707 | // A function cannot capture state in memory if it only reads memory, it can | ||||
4708 | // however return/throw state and the state might be influenced by the | ||||
4709 | // pointer value, e.g., loading from a returned pointer might reveal a bit. | ||||
4710 | if (F.onlyReadsMemory()) | ||||
4711 | State.addKnownBits(NOT_CAPTURED_IN_MEM); | ||||
4712 | |||||
4713 | // A function cannot communicate state back if it does not through | ||||
4714 | // exceptions and doesn not return values. | ||||
4715 | if (F.doesNotThrow() && F.getReturnType()->isVoidTy()) | ||||
4716 | State.addKnownBits(NOT_CAPTURED_IN_RET); | ||||
4717 | |||||
4718 | // Check existing "returned" attributes. | ||||
4719 | int ArgNo = IRP.getCalleeArgNo(); | ||||
4720 | if (F.doesNotThrow() && ArgNo >= 0) { | ||||
4721 | for (unsigned u = 0, e = F.arg_size(); u < e; ++u) | ||||
4722 | if (F.hasParamAttribute(u, Attribute::Returned)) { | ||||
4723 | if (u == unsigned(ArgNo)) | ||||
4724 | State.removeAssumedBits(NOT_CAPTURED_IN_RET); | ||||
4725 | else if (F.onlyReadsMemory()) | ||||
4726 | State.addKnownBits(NO_CAPTURE); | ||||
4727 | else | ||||
4728 | State.addKnownBits(NOT_CAPTURED_IN_RET); | ||||
4729 | break; | ||||
4730 | } | ||||
4731 | } | ||||
4732 | } | ||||
4733 | |||||
4734 | /// See AbstractState::getAsStr(). | ||||
4735 | const std::string getAsStr() const override { | ||||
4736 | if (isKnownNoCapture()) | ||||
4737 | return "known not-captured"; | ||||
4738 | if (isAssumedNoCapture()) | ||||
4739 | return "assumed not-captured"; | ||||
4740 | if (isKnownNoCaptureMaybeReturned()) | ||||
4741 | return "known not-captured-maybe-returned"; | ||||
4742 | if (isAssumedNoCaptureMaybeReturned()) | ||||
4743 | return "assumed not-captured-maybe-returned"; | ||||
4744 | return "assumed-captured"; | ||||
4745 | } | ||||
4746 | }; | ||||
4747 | |||||
4748 | /// Attributor-aware capture tracker. | ||||
4749 | struct AACaptureUseTracker final : public CaptureTracker { | ||||
4750 | |||||
4751 | /// Create a capture tracker that can lookup in-flight abstract attributes | ||||
4752 | /// through the Attributor \p A. | ||||
4753 | /// | ||||
4754 | /// If a use leads to a potential capture, \p CapturedInMemory is set and the | ||||
4755 | /// search is stopped. If a use leads to a return instruction, | ||||
4756 | /// \p CommunicatedBack is set to true and \p CapturedInMemory is not changed. | ||||
4757 | /// If a use leads to a ptr2int which may capture the value, | ||||
4758 | /// \p CapturedInInteger is set. If a use is found that is currently assumed | ||||
4759 | /// "no-capture-maybe-returned", the user is added to the \p PotentialCopies | ||||
4760 | /// set. All values in \p PotentialCopies are later tracked as well. For every | ||||
4761 | /// explored use we decrement \p RemainingUsesToExplore. Once it reaches 0, | ||||
4762 | /// the search is stopped with \p CapturedInMemory and \p CapturedInInteger | ||||
4763 | /// conservatively set to true. | ||||
4764 | AACaptureUseTracker(Attributor &A, AANoCapture &NoCaptureAA, | ||||
4765 | const AAIsDead &IsDeadAA, AANoCapture::StateType &State, | ||||
4766 | SmallSetVector<Value *, 4> &PotentialCopies, | ||||
4767 | unsigned &RemainingUsesToExplore) | ||||
4768 | : A(A), NoCaptureAA(NoCaptureAA), IsDeadAA(IsDeadAA), State(State), | ||||
4769 | PotentialCopies(PotentialCopies), | ||||
4770 | RemainingUsesToExplore(RemainingUsesToExplore) {} | ||||
4771 | |||||
4772 | /// Determine if \p V maybe captured. *Also updates the state!* | ||||
4773 | bool valueMayBeCaptured(const Value *V) { | ||||
4774 | if (V->getType()->isPointerTy()) { | ||||
4775 | PointerMayBeCaptured(V, this); | ||||
4776 | } else { | ||||
4777 | State.indicatePessimisticFixpoint(); | ||||
4778 | } | ||||
4779 | return State.isAssumed(AANoCapture::NO_CAPTURE_MAYBE_RETURNED); | ||||
4780 | } | ||||
4781 | |||||
4782 | /// See CaptureTracker::tooManyUses(). | ||||
4783 | void tooManyUses() override { | ||||
4784 | State.removeAssumedBits(AANoCapture::NO_CAPTURE); | ||||
4785 | } | ||||
4786 | |||||
4787 | bool isDereferenceableOrNull(Value *O, const DataLayout &DL) override { | ||||
4788 | if (CaptureTracker::isDereferenceableOrNull(O, DL)) | ||||
4789 | return true; | ||||
4790 | const auto &DerefAA = A.getAAFor<AADereferenceable>( | ||||
4791 | NoCaptureAA, IRPosition::value(*O), DepClassTy::OPTIONAL); | ||||
4792 | return DerefAA.getAssumedDereferenceableBytes(); | ||||
4793 | } | ||||
4794 | |||||
4795 | /// See CaptureTracker::captured(...). | ||||
4796 | bool captured(const Use *U) override { | ||||
4797 | Instruction *UInst = cast<Instruction>(U->getUser()); | ||||
4798 | LLVM_DEBUG(dbgs() << "Check use: " << *U->get() << " in " << *UInstdo { } while (false) | ||||
4799 | << "\n")do { } while (false); | ||||
4800 | |||||
4801 | // Because we may reuse the tracker multiple times we keep track of the | ||||
4802 | // number of explored uses ourselves as well. | ||||
4803 | if (RemainingUsesToExplore-- == 0) { | ||||
4804 | LLVM_DEBUG(dbgs() << " - too many uses to explore!\n")do { } while (false); | ||||
4805 | return isCapturedIn(/* Memory */ true, /* Integer */ true, | ||||
4806 | /* Return */ true); | ||||
4807 | } | ||||
4808 | |||||
4809 | // Deal with ptr2int by following uses. | ||||
4810 | if (isa<PtrToIntInst>(UInst)) { | ||||
4811 | LLVM_DEBUG(dbgs() << " - ptr2int assume the worst!\n")do { } while (false); | ||||
4812 | return valueMayBeCaptured(UInst); | ||||
4813 | } | ||||
4814 | |||||
4815 | // For stores we check if we can follow the value through memory or not. | ||||
4816 | if (auto *SI = dyn_cast<StoreInst>(UInst)) { | ||||
4817 | if (SI->isVolatile()) | ||||
4818 | return isCapturedIn(/* Memory */ true, /* Integer */ false, | ||||
4819 | /* Return */ false); | ||||
4820 | bool UsedAssumedInformation = false; | ||||
4821 | if (!AA::getPotentialCopiesOfStoredValue( | ||||
4822 | A, *SI, PotentialCopies, NoCaptureAA, UsedAssumedInformation)) | ||||
4823 | return isCapturedIn(/* Memory */ true, /* Integer */ false, | ||||
4824 | /* Return */ false); | ||||
4825 | // Not captured directly, potential copies will be checked. | ||||
4826 | return isCapturedIn(/* Memory */ false, /* Integer */ false, | ||||
4827 | /* Return */ false); | ||||
4828 | } | ||||
4829 | |||||
4830 | // Explicitly catch return instructions. | ||||
4831 | if (isa<ReturnInst>(UInst)) { | ||||
4832 | if (UInst->getFunction() == NoCaptureAA.getAnchorScope()) | ||||
4833 | return isCapturedIn(/* Memory */ false, /* Integer */ false, | ||||
4834 | /* Return */ true); | ||||
4835 | return isCapturedIn(/* Memory */ true, /* Integer */ true, | ||||
4836 | /* Return */ true); | ||||
4837 | } | ||||
4838 | |||||
4839 | // For now we only use special logic for call sites. However, the tracker | ||||
4840 | // itself knows about a lot of other non-capturing cases already. | ||||
4841 | auto *CB = dyn_cast<CallBase>(UInst); | ||||
4842 | if (!CB || !CB->isArgOperand(U)) | ||||
4843 | return isCapturedIn(/* Memory */ true, /* Integer */ true, | ||||
4844 | /* Return */ true); | ||||
4845 | |||||
4846 | unsigned ArgNo = CB->getArgOperandNo(U); | ||||
4847 | const IRPosition &CSArgPos = IRPosition::callsite_argument(*CB, ArgNo); | ||||
4848 | // If we have a abstract no-capture attribute for the argument we can use | ||||
4849 | // it to justify a non-capture attribute here. This allows recursion! | ||||
4850 | auto &ArgNoCaptureAA = | ||||
4851 | A.getAAFor<AANoCapture>(NoCaptureAA, CSArgPos, DepClassTy::REQUIRED); | ||||
4852 | if (ArgNoCaptureAA.isAssumedNoCapture()) | ||||
4853 | return isCapturedIn(/* Memory */ false, /* Integer */ false, | ||||
4854 | /* Return */ false); | ||||
4855 | if (ArgNoCaptureAA.isAssumedNoCaptureMaybeReturned()) { | ||||
4856 | addPotentialCopy(*CB); | ||||
4857 | return isCapturedIn(/* Memory */ false, /* Integer */ false, | ||||
4858 | /* Return */ false); | ||||
4859 | } | ||||
4860 | |||||
4861 | // Lastly, we could not find a reason no-capture can be assumed so we don't. | ||||
4862 | return isCapturedIn(/* Memory */ true, /* Integer */ true, | ||||
4863 | /* Return */ true); | ||||
4864 | } | ||||
4865 | |||||
4866 | /// Register \p CS as potential copy of the value we are checking. | ||||
4867 | void addPotentialCopy(CallBase &CB) { PotentialCopies.insert(&CB); } | ||||
4868 | |||||
4869 | /// See CaptureTracker::shouldExplore(...). | ||||
4870 | bool shouldExplore(const Use *U) override { | ||||
4871 | // Check liveness and ignore droppable users. | ||||
4872 | bool UsedAssumedInformation = false; | ||||
4873 | return !U->getUser()->isDroppable() && | ||||
4874 | !A.isAssumedDead(*U, &NoCaptureAA, &IsDeadAA, | ||||
4875 | UsedAssumedInformation); | ||||
4876 | } | ||||
4877 | |||||
4878 | /// Update the state according to \p CapturedInMem, \p CapturedInInt, and | ||||
4879 | /// \p CapturedInRet, then return the appropriate value for use in the | ||||
4880 | /// CaptureTracker::captured() interface. | ||||
4881 | bool isCapturedIn(bool CapturedInMem, bool CapturedInInt, | ||||
4882 | bool CapturedInRet) { | ||||
4883 | LLVM_DEBUG(dbgs() << " - captures [Mem " << CapturedInMem << "|Int "do { } while (false) | ||||
4884 | << CapturedInInt << "|Ret " << CapturedInRet << "]\n")do { } while (false); | ||||
4885 | if (CapturedInMem) | ||||
4886 | State.removeAssumedBits(AANoCapture::NOT_CAPTURED_IN_MEM); | ||||
4887 | if (CapturedInInt) | ||||
4888 | State.removeAssumedBits(AANoCapture::NOT_CAPTURED_IN_INT); | ||||
4889 | if (CapturedInRet) | ||||
4890 | State.removeAssumedBits(AANoCapture::NOT_CAPTURED_IN_RET); | ||||
4891 | return !State.isAssumed(AANoCapture::NO_CAPTURE_MAYBE_RETURNED); | ||||
4892 | } | ||||
4893 | |||||
4894 | private: | ||||
4895 | /// The attributor providing in-flight abstract attributes. | ||||
4896 | Attributor &A; | ||||
4897 | |||||
4898 | /// The abstract attribute currently updated. | ||||
4899 | AANoCapture &NoCaptureAA; | ||||
4900 | |||||
4901 | /// The abstract liveness state. | ||||
4902 | const AAIsDead &IsDeadAA; | ||||
4903 | |||||
4904 | /// The state currently updated. | ||||
4905 | AANoCapture::StateType &State; | ||||
4906 | |||||
4907 | /// Set of potential copies of the tracked value. | ||||
4908 | SmallSetVector<Value *, 4> &PotentialCopies; | ||||
4909 | |||||
4910 | /// Global counter to limit the number of explored uses. | ||||
4911 | unsigned &RemainingUsesToExplore; | ||||
4912 | }; | ||||
4913 | |||||
4914 | ChangeStatus AANoCaptureImpl::updateImpl(Attributor &A) { | ||||
4915 | const IRPosition &IRP = getIRPosition(); | ||||
4916 | Value *V = isArgumentPosition() ? IRP.getAssociatedArgument() | ||||
4917 | : &IRP.getAssociatedValue(); | ||||
4918 | if (!V) | ||||
4919 | return indicatePessimisticFixpoint(); | ||||
4920 | |||||
4921 | const Function *F = | ||||
4922 | isArgumentPosition() ? IRP.getAssociatedFunction() : IRP.getAnchorScope(); | ||||
4923 | assert(F && "Expected a function!")(static_cast<void> (0)); | ||||
4924 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
4925 | const auto &IsDeadAA = A.getAAFor<AAIsDead>(*this, FnPos, DepClassTy::NONE); | ||||
4926 | |||||
4927 | AANoCapture::StateType T; | ||||
4928 | |||||
4929 | // Readonly means we cannot capture through memory. | ||||
4930 | const auto &FnMemAA = | ||||
4931 | A.getAAFor<AAMemoryBehavior>(*this, FnPos, DepClassTy::NONE); | ||||
4932 | if (FnMemAA.isAssumedReadOnly()) { | ||||
4933 | T.addKnownBits(NOT_CAPTURED_IN_MEM); | ||||
4934 | if (FnMemAA.isKnownReadOnly()) | ||||
4935 | addKnownBits(NOT_CAPTURED_IN_MEM); | ||||
4936 | else | ||||
4937 | A.recordDependence(FnMemAA, *this, DepClassTy::OPTIONAL); | ||||
4938 | } | ||||
4939 | |||||
4940 | // Make sure all returned values are different than the underlying value. | ||||
4941 | // TODO: we could do this in a more sophisticated way inside | ||||
4942 | // AAReturnedValues, e.g., track all values that escape through returns | ||||
4943 | // directly somehow. | ||||
4944 | auto CheckReturnedArgs = [&](const AAReturnedValues &RVAA) { | ||||
4945 | bool SeenConstant = false; | ||||
4946 | for (auto &It : RVAA.returned_values()) { | ||||
4947 | if (isa<Constant>(It.first)) { | ||||
4948 | if (SeenConstant) | ||||
4949 | return false; | ||||
4950 | SeenConstant = true; | ||||
4951 | } else if (!isa<Argument>(It.first) || | ||||
4952 | It.first == getAssociatedArgument()) | ||||
4953 | return false; | ||||
4954 | } | ||||
4955 | return true; | ||||
4956 | }; | ||||
4957 | |||||
4958 | const auto &NoUnwindAA = | ||||
4959 | A.getAAFor<AANoUnwind>(*this, FnPos, DepClassTy::OPTIONAL); | ||||
4960 | if (NoUnwindAA.isAssumedNoUnwind()) { | ||||
4961 | bool IsVoidTy = F->getReturnType()->isVoidTy(); | ||||
4962 | const AAReturnedValues *RVAA = | ||||
4963 | IsVoidTy ? nullptr | ||||
4964 | : &A.getAAFor<AAReturnedValues>(*this, FnPos, | ||||
4965 | |||||
4966 | DepClassTy::OPTIONAL); | ||||
4967 | if (IsVoidTy || CheckReturnedArgs(*RVAA)) { | ||||
4968 | T.addKnownBits(NOT_CAPTURED_IN_RET); | ||||
4969 | if (T.isKnown(NOT_CAPTURED_IN_MEM)) | ||||
4970 | return ChangeStatus::UNCHANGED; | ||||
4971 | if (NoUnwindAA.isKnownNoUnwind() && | ||||
4972 | (IsVoidTy || RVAA->getState().isAtFixpoint())) { | ||||
4973 | addKnownBits(NOT_CAPTURED_IN_RET); | ||||
4974 | if (isKnown(NOT_CAPTURED_IN_MEM)) | ||||
4975 | return indicateOptimisticFixpoint(); | ||||
4976 | } | ||||
4977 | } | ||||
4978 | } | ||||
4979 | |||||
4980 | // Use the CaptureTracker interface and logic with the specialized tracker, | ||||
4981 | // defined in AACaptureUseTracker, that can look at in-flight abstract | ||||
4982 | // attributes and directly updates the assumed state. | ||||
4983 | SmallSetVector<Value *, 4> PotentialCopies; | ||||
4984 | unsigned RemainingUsesToExplore = | ||||
4985 | getDefaultMaxUsesToExploreForCaptureTracking(); | ||||
4986 | AACaptureUseTracker Tracker(A, *this, IsDeadAA, T, PotentialCopies, | ||||
4987 | RemainingUsesToExplore); | ||||
4988 | |||||
4989 | // Check all potential copies of the associated value until we can assume | ||||
4990 | // none will be captured or we have to assume at least one might be. | ||||
4991 | unsigned Idx = 0; | ||||
4992 | PotentialCopies.insert(V); | ||||
4993 | while (T.isAssumed(NO_CAPTURE_MAYBE_RETURNED) && Idx < PotentialCopies.size()) | ||||
4994 | Tracker.valueMayBeCaptured(PotentialCopies[Idx++]); | ||||
4995 | |||||
4996 | AANoCapture::StateType &S = getState(); | ||||
4997 | auto Assumed = S.getAssumed(); | ||||
4998 | S.intersectAssumedBits(T.getAssumed()); | ||||
4999 | if (!isAssumedNoCaptureMaybeReturned()) | ||||
5000 | return indicatePessimisticFixpoint(); | ||||
5001 | return Assumed == S.getAssumed() ? ChangeStatus::UNCHANGED | ||||
5002 | : ChangeStatus::CHANGED; | ||||
5003 | } | ||||
5004 | |||||
5005 | /// NoCapture attribute for function arguments. | ||||
5006 | struct AANoCaptureArgument final : AANoCaptureImpl { | ||||
5007 | AANoCaptureArgument(const IRPosition &IRP, Attributor &A) | ||||
5008 | : AANoCaptureImpl(IRP, A) {} | ||||
5009 | |||||
5010 | /// See AbstractAttribute::trackStatistics() | ||||
5011 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(nocapture){ static llvm::Statistic NumIRArguments_nocapture = {"attributor" , "NumIRArguments_nocapture", ("Number of " "arguments" " marked '" "nocapture" "'")};; ++(NumIRArguments_nocapture); } } | ||||
5012 | }; | ||||
5013 | |||||
5014 | /// NoCapture attribute for call site arguments. | ||||
5015 | struct AANoCaptureCallSiteArgument final : AANoCaptureImpl { | ||||
5016 | AANoCaptureCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
5017 | : AANoCaptureImpl(IRP, A) {} | ||||
5018 | |||||
5019 | /// See AbstractAttribute::initialize(...). | ||||
5020 | void initialize(Attributor &A) override { | ||||
5021 | if (Argument *Arg = getAssociatedArgument()) | ||||
5022 | if (Arg->hasByValAttr()) | ||||
5023 | indicateOptimisticFixpoint(); | ||||
5024 | AANoCaptureImpl::initialize(A); | ||||
5025 | } | ||||
5026 | |||||
5027 | /// See AbstractAttribute::updateImpl(...). | ||||
5028 | ChangeStatus updateImpl(Attributor &A) override { | ||||
5029 | // TODO: Once we have call site specific value information we can provide | ||||
5030 | // call site specific liveness information and then it makes | ||||
5031 | // sense to specialize attributes for call sites arguments instead of | ||||
5032 | // redirecting requests to the callee argument. | ||||
5033 | Argument *Arg = getAssociatedArgument(); | ||||
5034 | if (!Arg) | ||||
5035 | return indicatePessimisticFixpoint(); | ||||
5036 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||
5037 | auto &ArgAA = A.getAAFor<AANoCapture>(*this, ArgPos, DepClassTy::REQUIRED); | ||||
5038 | return clampStateAndIndicateChange(getState(), ArgAA.getState()); | ||||
5039 | } | ||||
5040 | |||||
5041 | /// See AbstractAttribute::trackStatistics() | ||||
5042 | void trackStatistics() const override{STATS_DECLTRACK_CSARG_ATTR(nocapture){ static llvm::Statistic NumIRCSArguments_nocapture = {"attributor" , "NumIRCSArguments_nocapture", ("Number of " "call site arguments" " marked '" "nocapture" "'")};; ++(NumIRCSArguments_nocapture ); }}; | ||||
5043 | }; | ||||
5044 | |||||
5045 | /// NoCapture attribute for floating values. | ||||
5046 | struct AANoCaptureFloating final : AANoCaptureImpl { | ||||
5047 | AANoCaptureFloating(const IRPosition &IRP, Attributor &A) | ||||
5048 | : AANoCaptureImpl(IRP, A) {} | ||||
5049 | |||||
5050 | /// See AbstractAttribute::trackStatistics() | ||||
5051 | void trackStatistics() const override { | ||||
5052 | STATS_DECLTRACK_FLOATING_ATTR(nocapture){ static llvm::Statistic NumIRFloating_nocapture = {"attributor" , "NumIRFloating_nocapture", ("Number of floating values known to be '" "nocapture" "'")};; ++(NumIRFloating_nocapture); } | ||||
5053 | } | ||||
5054 | }; | ||||
5055 | |||||
5056 | /// NoCapture attribute for function return value. | ||||
5057 | struct AANoCaptureReturned final : AANoCaptureImpl { | ||||
5058 | AANoCaptureReturned(const IRPosition &IRP, Attributor &A) | ||||
5059 | : AANoCaptureImpl(IRP, A) { | ||||
5060 | llvm_unreachable("NoCapture is not applicable to function returns!")__builtin_unreachable(); | ||||
5061 | } | ||||
5062 | |||||
5063 | /// See AbstractAttribute::initialize(...). | ||||
5064 | void initialize(Attributor &A) override { | ||||
5065 | llvm_unreachable("NoCapture is not applicable to function returns!")__builtin_unreachable(); | ||||
5066 | } | ||||
5067 | |||||
5068 | /// See AbstractAttribute::updateImpl(...). | ||||
5069 | ChangeStatus updateImpl(Attributor &A) override { | ||||
5070 | llvm_unreachable("NoCapture is not applicable to function returns!")__builtin_unreachable(); | ||||
5071 | } | ||||
5072 | |||||
5073 | /// See AbstractAttribute::trackStatistics() | ||||
5074 | void trackStatistics() const override {} | ||||
5075 | }; | ||||
5076 | |||||
5077 | /// NoCapture attribute deduction for a call site return value. | ||||
5078 | struct AANoCaptureCallSiteReturned final : AANoCaptureImpl { | ||||
5079 | AANoCaptureCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
5080 | : AANoCaptureImpl(IRP, A) {} | ||||
5081 | |||||
5082 | /// See AbstractAttribute::initialize(...). | ||||
5083 | void initialize(Attributor &A) override { | ||||
5084 | const Function *F = getAnchorScope(); | ||||
5085 | // Check what state the associated function can actually capture. | ||||
5086 | determineFunctionCaptureCapabilities(getIRPosition(), *F, *this); | ||||
5087 | } | ||||
5088 | |||||
5089 | /// See AbstractAttribute::trackStatistics() | ||||
5090 | void trackStatistics() const override { | ||||
5091 | STATS_DECLTRACK_CSRET_ATTR(nocapture){ static llvm::Statistic NumIRCSReturn_nocapture = {"attributor" , "NumIRCSReturn_nocapture", ("Number of " "call site returns" " marked '" "nocapture" "'")};; ++(NumIRCSReturn_nocapture); } | ||||
5092 | } | ||||
5093 | }; | ||||
5094 | |||||
5095 | /// ------------------ Value Simplify Attribute ---------------------------- | ||||
5096 | |||||
5097 | bool ValueSimplifyStateType::unionAssumed(Optional<Value *> Other) { | ||||
5098 | // FIXME: Add a typecast support. | ||||
5099 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||
5100 | SimplifiedAssociatedValue, Other, Ty); | ||||
5101 | if (SimplifiedAssociatedValue == Optional<Value *>(nullptr)) | ||||
5102 | return false; | ||||
5103 | |||||
5104 | LLVM_DEBUG({do { } while (false) | ||||
5105 | if (SimplifiedAssociatedValue.hasValue())do { } while (false) | ||||
5106 | dbgs() << "[ValueSimplify] is assumed to be "do { } while (false) | ||||
5107 | << **SimplifiedAssociatedValue << "\n";do { } while (false) | ||||
5108 | elsedo { } while (false) | ||||
5109 | dbgs() << "[ValueSimplify] is assumed to be <none>\n";do { } while (false) | ||||
5110 | })do { } while (false); | ||||
5111 | return true; | ||||
5112 | } | ||||
5113 | |||||
5114 | struct AAValueSimplifyImpl : AAValueSimplify { | ||||
5115 | AAValueSimplifyImpl(const IRPosition &IRP, Attributor &A) | ||||
5116 | : AAValueSimplify(IRP, A) {} | ||||
5117 | |||||
5118 | /// See AbstractAttribute::initialize(...). | ||||
5119 | void initialize(Attributor &A) override { | ||||
5120 | if (getAssociatedValue().getType()->isVoidTy()) | ||||
5121 | indicatePessimisticFixpoint(); | ||||
5122 | if (A.hasSimplificationCallback(getIRPosition())) | ||||
5123 | indicatePessimisticFixpoint(); | ||||
5124 | } | ||||
5125 | |||||
5126 | /// See AbstractAttribute::getAsStr(). | ||||
5127 | const std::string getAsStr() const override { | ||||
5128 | LLVM_DEBUG({do { } while (false) | ||||
5129 | errs() << "SAV: " << SimplifiedAssociatedValue << " ";do { } while (false) | ||||
5130 | if (SimplifiedAssociatedValue && *SimplifiedAssociatedValue)do { } while (false) | ||||
5131 | errs() << "SAV: " << **SimplifiedAssociatedValue << " ";do { } while (false) | ||||
5132 | })do { } while (false); | ||||
5133 | return isValidState() ? (isAtFixpoint() ? "simplified" : "maybe-simple") | ||||
5134 | : "not-simple"; | ||||
5135 | } | ||||
5136 | |||||
5137 | /// See AbstractAttribute::trackStatistics() | ||||
5138 | void trackStatistics() const override {} | ||||
5139 | |||||
5140 | /// See AAValueSimplify::getAssumedSimplifiedValue() | ||||
5141 | Optional<Value *> getAssumedSimplifiedValue(Attributor &A) const override { | ||||
5142 | return SimplifiedAssociatedValue; | ||||
5143 | } | ||||
5144 | |||||
5145 | /// Return a value we can use as replacement for the associated one, or | ||||
5146 | /// nullptr if we don't have one that makes sense. | ||||
5147 | Value *getReplacementValue(Attributor &A) const { | ||||
5148 | Value *NewV; | ||||
5149 | NewV = SimplifiedAssociatedValue.hasValue() | ||||
5150 | ? SimplifiedAssociatedValue.getValue() | ||||
5151 | : UndefValue::get(getAssociatedType()); | ||||
5152 | if (!NewV) | ||||
5153 | return nullptr; | ||||
5154 | NewV = AA::getWithType(*NewV, *getAssociatedType()); | ||||
5155 | if (!NewV || NewV == &getAssociatedValue()) | ||||
5156 | return nullptr; | ||||
5157 | const Instruction *CtxI = getCtxI(); | ||||
5158 | if (CtxI && !AA::isValidAtPosition(*NewV, *CtxI, A.getInfoCache())) | ||||
5159 | return nullptr; | ||||
5160 | if (!CtxI && !AA::isValidInScope(*NewV, getAnchorScope())) | ||||
5161 | return nullptr; | ||||
5162 | return NewV; | ||||
5163 | } | ||||
5164 | |||||
5165 | /// Helper function for querying AAValueSimplify and updating candicate. | ||||
5166 | /// \param IRP The value position we are trying to unify with SimplifiedValue | ||||
5167 | bool checkAndUpdate(Attributor &A, const AbstractAttribute &QueryingAA, | ||||
5168 | const IRPosition &IRP, bool Simplify = true) { | ||||
5169 | bool UsedAssumedInformation = false; | ||||
5170 | Optional<Value *> QueryingValueSimplified = &IRP.getAssociatedValue(); | ||||
5171 | if (Simplify) | ||||
5172 | QueryingValueSimplified = | ||||
5173 | A.getAssumedSimplified(IRP, QueryingAA, UsedAssumedInformation); | ||||
5174 | return unionAssumed(QueryingValueSimplified); | ||||
5175 | } | ||||
5176 | |||||
5177 | /// Returns a candidate is found or not | ||||
5178 | template <typename AAType> bool askSimplifiedValueFor(Attributor &A) { | ||||
5179 | if (!getAssociatedValue().getType()->isIntegerTy()) | ||||
5180 | return false; | ||||
5181 | |||||
5182 | // This will also pass the call base context. | ||||
5183 | const auto &AA = | ||||
5184 | A.getAAFor<AAType>(*this, getIRPosition(), DepClassTy::NONE); | ||||
5185 | |||||
5186 | Optional<ConstantInt *> COpt = AA.getAssumedConstantInt(A); | ||||
5187 | |||||
5188 | if (!COpt.hasValue()) { | ||||
5189 | SimplifiedAssociatedValue = llvm::None; | ||||
5190 | A.recordDependence(AA, *this, DepClassTy::OPTIONAL); | ||||
5191 | return true; | ||||
5192 | } | ||||
5193 | if (auto *C = COpt.getValue()) { | ||||
5194 | SimplifiedAssociatedValue = C; | ||||
5195 | A.recordDependence(AA, *this, DepClassTy::OPTIONAL); | ||||
5196 | return true; | ||||
5197 | } | ||||
5198 | return false; | ||||
5199 | } | ||||
5200 | |||||
5201 | bool askSimplifiedValueForOtherAAs(Attributor &A) { | ||||
5202 | if (askSimplifiedValueFor<AAValueConstantRange>(A)) | ||||
5203 | return true; | ||||
5204 | if (askSimplifiedValueFor<AAPotentialValues>(A)) | ||||
5205 | return true; | ||||
5206 | return false; | ||||
5207 | } | ||||
5208 | |||||
5209 | /// See AbstractAttribute::manifest(...). | ||||
5210 | ChangeStatus manifest(Attributor &A) override { | ||||
5211 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
5212 | if (getAssociatedValue().user_empty()) | ||||
5213 | return Changed; | ||||
5214 | |||||
5215 | if (auto *NewV = getReplacementValue(A)) { | ||||
5216 | LLVM_DEBUG(dbgs() << "[ValueSimplify] " << getAssociatedValue() << " -> "do { } while (false) | ||||
5217 | << *NewV << " :: " << *this << "\n")do { } while (false); | ||||
5218 | if (A.changeValueAfterManifest(getAssociatedValue(), *NewV)) | ||||
5219 | Changed = ChangeStatus::CHANGED; | ||||
5220 | } | ||||
5221 | |||||
5222 | return Changed | AAValueSimplify::manifest(A); | ||||
5223 | } | ||||
5224 | |||||
5225 | /// See AbstractState::indicatePessimisticFixpoint(...). | ||||
5226 | ChangeStatus indicatePessimisticFixpoint() override { | ||||
5227 | SimplifiedAssociatedValue = &getAssociatedValue(); | ||||
5228 | return AAValueSimplify::indicatePessimisticFixpoint(); | ||||
5229 | } | ||||
5230 | |||||
5231 | static bool handleLoad(Attributor &A, const AbstractAttribute &AA, | ||||
5232 | LoadInst &L, function_ref<bool(Value &)> Union) { | ||||
5233 | auto UnionWrapper = [&](Value &V, Value &Obj) { | ||||
5234 | if (isa<AllocaInst>(Obj)) | ||||
5235 | return Union(V); | ||||
5236 | if (!AA::isDynamicallyUnique(A, AA, V)) | ||||
5237 | return false; | ||||
5238 | if (!AA::isValidAtPosition(V, L, A.getInfoCache())) | ||||
5239 | return false; | ||||
5240 | return Union(V); | ||||
5241 | }; | ||||
5242 | |||||
5243 | Value &Ptr = *L.getPointerOperand(); | ||||
5244 | SmallVector<Value *, 8> Objects; | ||||
5245 | if (!AA::getAssumedUnderlyingObjects(A, Ptr, Objects, AA, &L)) | ||||
5246 | return false; | ||||
5247 | |||||
5248 | for (Value *Obj : Objects) { | ||||
5249 | LLVM_DEBUG(dbgs() << "Visit underlying object " << *Obj << "\n")do { } while (false); | ||||
5250 | if (isa<UndefValue>(Obj)) | ||||
5251 | continue; | ||||
5252 | if (isa<ConstantPointerNull>(Obj)) { | ||||
5253 | // A null pointer access can be undefined but any offset from null may | ||||
5254 | // be OK. We do not try to optimize the latter. | ||||
5255 | bool UsedAssumedInformation = false; | ||||
5256 | if (!NullPointerIsDefined(L.getFunction(), | ||||
5257 | Ptr.getType()->getPointerAddressSpace()) && | ||||
5258 | A.getAssumedSimplified(Ptr, AA, UsedAssumedInformation) == Obj) | ||||
5259 | continue; | ||||
5260 | return false; | ||||
5261 | } | ||||
5262 | if (!isa<AllocaInst>(Obj) && !isa<GlobalVariable>(Obj)) | ||||
5263 | return false; | ||||
5264 | Constant *InitialVal = AA::getInitialValueForObj(*Obj, *L.getType()); | ||||
5265 | if (!InitialVal || !Union(*InitialVal)) | ||||
5266 | return false; | ||||
5267 | |||||
5268 | LLVM_DEBUG(dbgs() << "Underlying object amenable to load-store "do { } while (false) | ||||
5269 | "propagation, checking accesses next.\n")do { } while (false); | ||||
5270 | |||||
5271 | auto CheckAccess = [&](const AAPointerInfo::Access &Acc, bool IsExact) { | ||||
5272 | LLVM_DEBUG(dbgs() << " - visit access " << Acc << "\n")do { } while (false); | ||||
5273 | if (!Acc.isWrite()) | ||||
5274 | return true; | ||||
5275 | if (Acc.isWrittenValueYetUndetermined()) | ||||
5276 | return true; | ||||
5277 | Value *Content = Acc.getWrittenValue(); | ||||
5278 | if (!Content) | ||||
5279 | return false; | ||||
5280 | Value *CastedContent = | ||||
5281 | AA::getWithType(*Content, *AA.getAssociatedType()); | ||||
5282 | if (!CastedContent) | ||||
5283 | return false; | ||||
5284 | if (IsExact) | ||||
5285 | return UnionWrapper(*CastedContent, *Obj); | ||||
5286 | if (auto *C = dyn_cast<Constant>(CastedContent)) | ||||
5287 | if (C->isNullValue() || C->isAllOnesValue() || isa<UndefValue>(C)) | ||||
5288 | return UnionWrapper(*CastedContent, *Obj); | ||||
5289 | return false; | ||||
5290 | }; | ||||
5291 | |||||
5292 | auto &PI = A.getAAFor<AAPointerInfo>(AA, IRPosition::value(*Obj), | ||||
5293 | DepClassTy::REQUIRED); | ||||
5294 | if (!PI.forallInterferingAccesses(L, CheckAccess)) | ||||
5295 | return false; | ||||
5296 | } | ||||
5297 | return true; | ||||
5298 | } | ||||
5299 | }; | ||||
5300 | |||||
5301 | struct AAValueSimplifyArgument final : AAValueSimplifyImpl { | ||||
5302 | AAValueSimplifyArgument(const IRPosition &IRP, Attributor &A) | ||||
5303 | : AAValueSimplifyImpl(IRP, A) {} | ||||
5304 | |||||
5305 | void initialize(Attributor &A) override { | ||||
5306 | AAValueSimplifyImpl::initialize(A); | ||||
5307 | if (!getAnchorScope() || getAnchorScope()->isDeclaration()) | ||||
5308 | indicatePessimisticFixpoint(); | ||||
5309 | if (hasAttr({Attribute::InAlloca, Attribute::Preallocated, | ||||
5310 | Attribute::StructRet, Attribute::Nest, Attribute::ByVal}, | ||||
5311 | /* IgnoreSubsumingPositions */ true)) | ||||
5312 | indicatePessimisticFixpoint(); | ||||
5313 | |||||
5314 | // FIXME: This is a hack to prevent us from propagating function poiner in | ||||
5315 | // the new pass manager CGSCC pass as it creates call edges the | ||||
5316 | // CallGraphUpdater cannot handle yet. | ||||
5317 | Value &V = getAssociatedValue(); | ||||
5318 | if (V.getType()->isPointerTy() && | ||||
5319 | V.getType()->getPointerElementType()->isFunctionTy() && | ||||
5320 | !A.isModulePass()) | ||||
5321 | indicatePessimisticFixpoint(); | ||||
5322 | } | ||||
5323 | |||||
5324 | /// See AbstractAttribute::updateImpl(...). | ||||
5325 | ChangeStatus updateImpl(Attributor &A) override { | ||||
5326 | // Byval is only replacable if it is readonly otherwise we would write into | ||||
5327 | // the replaced value and not the copy that byval creates implicitly. | ||||
5328 | Argument *Arg = getAssociatedArgument(); | ||||
5329 | if (Arg->hasByValAttr()) { | ||||
5330 | // TODO: We probably need to verify synchronization is not an issue, e.g., | ||||
5331 | // there is no race by not copying a constant byval. | ||||
5332 | const auto &MemAA = A.getAAFor<AAMemoryBehavior>(*this, getIRPosition(), | ||||
5333 | DepClassTy::REQUIRED); | ||||
5334 | if (!MemAA.isAssumedReadOnly()) | ||||
5335 | return indicatePessimisticFixpoint(); | ||||
5336 | } | ||||
5337 | |||||
5338 | auto Before = SimplifiedAssociatedValue; | ||||
5339 | |||||
5340 | auto PredForCallSite = [&](AbstractCallSite ACS) { | ||||
5341 | const IRPosition &ACSArgPos = | ||||
5342 | IRPosition::callsite_argument(ACS, getCallSiteArgNo()); | ||||
5343 | // Check if a coresponding argument was found or if it is on not | ||||
5344 | // associated (which can happen for callback calls). | ||||
5345 | if (ACSArgPos.getPositionKind() == IRPosition::IRP_INVALID) | ||||
5346 | return false; | ||||
5347 | |||||
5348 | // Simplify the argument operand explicitly and check if the result is | ||||
5349 | // valid in the current scope. This avoids refering to simplified values | ||||
5350 | // in other functions, e.g., we don't want to say a an argument in a | ||||
5351 | // static function is actually an argument in a different function. | ||||
5352 | bool UsedAssumedInformation = false; | ||||
5353 | Optional<Constant *> SimpleArgOp = | ||||
5354 | A.getAssumedConstant(ACSArgPos, *this, UsedAssumedInformation); | ||||
5355 | if (!SimpleArgOp.hasValue()) | ||||
5356 | return true; | ||||
5357 | if (!SimpleArgOp.getValue()) | ||||
5358 | return false; | ||||
5359 | if (!AA::isDynamicallyUnique(A, *this, **SimpleArgOp)) | ||||
5360 | return false; | ||||
5361 | return unionAssumed(*SimpleArgOp); | ||||
5362 | }; | ||||
5363 | |||||
5364 | // Generate a answer specific to a call site context. | ||||
5365 | bool Success; | ||||
5366 | bool AllCallSitesKnown; | ||||
5367 | if (hasCallBaseContext() && | ||||
5368 | getCallBaseContext()->getCalledFunction() == Arg->getParent()) | ||||
5369 | Success = PredForCallSite( | ||||
5370 | AbstractCallSite(&getCallBaseContext()->getCalledOperandUse())); | ||||
5371 | else | ||||
5372 | Success = A.checkForAllCallSites(PredForCallSite, *this, true, | ||||
5373 | AllCallSitesKnown); | ||||
5374 | |||||
5375 | if (!Success) | ||||
5376 | if (!askSimplifiedValueForOtherAAs(A)) | ||||
5377 | return indicatePessimisticFixpoint(); | ||||
5378 | |||||
5379 | // If a candicate was found in this update, return CHANGED. | ||||
5380 | return Before == SimplifiedAssociatedValue ? ChangeStatus::UNCHANGED | ||||
5381 | : ChangeStatus ::CHANGED; | ||||
5382 | } | ||||
5383 | |||||
5384 | /// See AbstractAttribute::trackStatistics() | ||||
5385 | void trackStatistics() const override { | ||||
5386 | STATS_DECLTRACK_ARG_ATTR(value_simplify){ static llvm::Statistic NumIRArguments_value_simplify = {"attributor" , "NumIRArguments_value_simplify", ("Number of " "arguments" " marked '" "value_simplify" "'")};; ++(NumIRArguments_value_simplify); } | ||||
5387 | } | ||||
5388 | }; | ||||
5389 | |||||
5390 | struct AAValueSimplifyReturned : AAValueSimplifyImpl { | ||||
5391 | AAValueSimplifyReturned(const IRPosition &IRP, Attributor &A) | ||||
5392 | : AAValueSimplifyImpl(IRP, A) {} | ||||
5393 | |||||
5394 | /// See AAValueSimplify::getAssumedSimplifiedValue() | ||||
5395 | Optional<Value *> getAssumedSimplifiedValue(Attributor &A) const override { | ||||
5396 | if (!isValidState()) | ||||
5397 | return nullptr; | ||||
5398 | return SimplifiedAssociatedValue; | ||||
5399 | } | ||||
5400 | |||||
5401 | /// See AbstractAttribute::updateImpl(...). | ||||
5402 | ChangeStatus updateImpl(Attributor &A) override { | ||||
5403 | auto Before = SimplifiedAssociatedValue; | ||||
5404 | |||||
5405 | auto PredForReturned = [&](Value &V) { | ||||
5406 | return checkAndUpdate(A, *this, | ||||
5407 | IRPosition::value(V, getCallBaseContext())); | ||||
5408 | }; | ||||
5409 | |||||
5410 | if (!A.checkForAllReturnedValues(PredForReturned, *this)) | ||||
5411 | if (!askSimplifiedValueForOtherAAs(A)) | ||||
5412 | return indicatePessimisticFixpoint(); | ||||
5413 | |||||
5414 | // If a candicate was found in this update, return CHANGED. | ||||
5415 | return Before == SimplifiedAssociatedValue ? ChangeStatus::UNCHANGED | ||||
5416 | : ChangeStatus ::CHANGED; | ||||
5417 | } | ||||
5418 | |||||
5419 | ChangeStatus manifest(Attributor &A) override { | ||||
5420 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
5421 | |||||
5422 | if (auto *NewV = getReplacementValue(A)) { | ||||
5423 | auto PredForReturned = | ||||
5424 | [&](Value &, const SmallSetVector<ReturnInst *, 4> &RetInsts) { | ||||
5425 | for (ReturnInst *RI : RetInsts) { | ||||
5426 | Value *ReturnedVal = RI->getReturnValue(); | ||||
5427 | if (ReturnedVal == NewV || isa<UndefValue>(ReturnedVal)) | ||||
5428 | return true; | ||||
5429 | assert(RI->getFunction() == getAnchorScope() &&(static_cast<void> (0)) | ||||
5430 | "ReturnInst in wrong function!")(static_cast<void> (0)); | ||||
5431 | LLVM_DEBUG(dbgs()do { } while (false) | ||||
5432 | << "[ValueSimplify] " << *ReturnedVal << " -> "do { } while (false) | ||||
5433 | << *NewV << " in " << *RI << " :: " << *this << "\n")do { } while (false); | ||||
5434 | if (A.changeUseAfterManifest(RI->getOperandUse(0), *NewV)) | ||||
5435 | Changed = ChangeStatus::CHANGED; | ||||
5436 | } | ||||
5437 | return true; | ||||
5438 | }; | ||||
5439 | A.checkForAllReturnedValuesAndReturnInsts(PredForReturned, *this); | ||||
5440 | } | ||||
5441 | |||||
5442 | return Changed | AAValueSimplify::manifest(A); | ||||
5443 | } | ||||
5444 | |||||
5445 | /// See AbstractAttribute::trackStatistics() | ||||
5446 | void trackStatistics() const override { | ||||
5447 | STATS_DECLTRACK_FNRET_ATTR(value_simplify){ static llvm::Statistic NumIRFunctionReturn_value_simplify = {"attributor", "NumIRFunctionReturn_value_simplify", ("Number of " "function returns" " marked '" "value_simplify" "'")};; ++(NumIRFunctionReturn_value_simplify ); } | ||||
5448 | } | ||||
5449 | }; | ||||
5450 | |||||
5451 | struct AAValueSimplifyFloating : AAValueSimplifyImpl { | ||||
5452 | AAValueSimplifyFloating(const IRPosition &IRP, Attributor &A) | ||||
5453 | : AAValueSimplifyImpl(IRP, A) {} | ||||
5454 | |||||
5455 | /// See AbstractAttribute::initialize(...). | ||||
5456 | void initialize(Attributor &A) override { | ||||
5457 | AAValueSimplifyImpl::initialize(A); | ||||
5458 | Value &V = getAnchorValue(); | ||||
5459 | |||||
5460 | // TODO: add other stuffs | ||||
5461 | if (isa<Constant>(V)) | ||||
5462 | indicatePessimisticFixpoint(); | ||||
5463 | } | ||||
5464 | |||||
5465 | /// Check if \p Cmp is a comparison we can simplify. | ||||
5466 | /// | ||||
5467 | /// We handle multiple cases, one in which at least one operand is an | ||||
5468 | /// (assumed) nullptr. If so, try to simplify it using AANonNull on the other | ||||
5469 | /// operand. Return true if successful, in that case SimplifiedAssociatedValue | ||||
5470 | /// will be updated. | ||||
5471 | bool handleCmp(Attributor &A, CmpInst &Cmp) { | ||||
5472 | auto Union = [&](Value &V) { | ||||
5473 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||
5474 | SimplifiedAssociatedValue, &V, V.getType()); | ||||
5475 | return SimplifiedAssociatedValue != Optional<Value *>(nullptr); | ||||
5476 | }; | ||||
5477 | |||||
5478 | Value *LHS = Cmp.getOperand(0); | ||||
5479 | Value *RHS = Cmp.getOperand(1); | ||||
5480 | |||||
5481 | // Simplify the operands first. | ||||
5482 | bool UsedAssumedInformation = false; | ||||
5483 | const auto &SimplifiedLHS = | ||||
5484 | A.getAssumedSimplified(IRPosition::value(*LHS, getCallBaseContext()), | ||||
5485 | *this, UsedAssumedInformation); | ||||
5486 | if (!SimplifiedLHS.hasValue()) | ||||
5487 | return true; | ||||
5488 | if (!SimplifiedLHS.getValue()) | ||||
5489 | return false; | ||||
5490 | LHS = *SimplifiedLHS; | ||||
5491 | |||||
5492 | const auto &SimplifiedRHS = | ||||
5493 | A.getAssumedSimplified(IRPosition::value(*RHS, getCallBaseContext()), | ||||
5494 | *this, UsedAssumedInformation); | ||||
5495 | if (!SimplifiedRHS.hasValue()) | ||||
5496 | return true; | ||||
5497 | if (!SimplifiedRHS.getValue()) | ||||
5498 | return false; | ||||
5499 | RHS = *SimplifiedRHS; | ||||
5500 | |||||
5501 | LLVMContext &Ctx = Cmp.getContext(); | ||||
5502 | // Handle the trivial case first in which we don't even need to think about | ||||
5503 | // null or non-null. | ||||
5504 | if (LHS == RHS && (Cmp.isTrueWhenEqual() || Cmp.isFalseWhenEqual())) { | ||||
5505 | Constant *NewVal = | ||||
5506 | ConstantInt::get(Type::getInt1Ty(Ctx), Cmp.isTrueWhenEqual()); | ||||
5507 | if (!Union(*NewVal)) | ||||
5508 | return false; | ||||
5509 | if (!UsedAssumedInformation) | ||||
5510 | indicateOptimisticFixpoint(); | ||||
5511 | return true; | ||||
5512 | } | ||||
5513 | |||||
5514 | // From now on we only handle equalities (==, !=). | ||||
5515 | ICmpInst *ICmp = dyn_cast<ICmpInst>(&Cmp); | ||||
5516 | if (!ICmp || !ICmp->isEquality()) | ||||
5517 | return false; | ||||
5518 | |||||
5519 | bool LHSIsNull = isa<ConstantPointerNull>(LHS); | ||||
5520 | bool RHSIsNull = isa<ConstantPointerNull>(RHS); | ||||
5521 | if (!LHSIsNull && !RHSIsNull) | ||||
5522 | return false; | ||||
5523 | |||||
5524 | // Left is the nullptr ==/!= non-nullptr case. We'll use AANonNull on the | ||||
5525 | // non-nullptr operand and if we assume it's non-null we can conclude the | ||||
5526 | // result of the comparison. | ||||
5527 | assert((LHSIsNull || RHSIsNull) &&(static_cast<void> (0)) | ||||
5528 | "Expected nullptr versus non-nullptr comparison at this point")(static_cast<void> (0)); | ||||
5529 | |||||
5530 | // The index is the operand that we assume is not null. | ||||
5531 | unsigned PtrIdx = LHSIsNull; | ||||
5532 | auto &PtrNonNullAA = A.getAAFor<AANonNull>( | ||||
5533 | *this, IRPosition::value(*ICmp->getOperand(PtrIdx)), | ||||
5534 | DepClassTy::REQUIRED); | ||||
5535 | if (!PtrNonNullAA.isAssumedNonNull()) | ||||
5536 | return false; | ||||
5537 | UsedAssumedInformation |= !PtrNonNullAA.isKnownNonNull(); | ||||
5538 | |||||
5539 | // The new value depends on the predicate, true for != and false for ==. | ||||
5540 | Constant *NewVal = ConstantInt::get( | ||||
5541 | Type::getInt1Ty(Ctx), ICmp->getPredicate() == CmpInst::ICMP_NE); | ||||
5542 | if (!Union(*NewVal)) | ||||
5543 | return false; | ||||
5544 | |||||
5545 | if (!UsedAssumedInformation) | ||||
5546 | indicateOptimisticFixpoint(); | ||||
5547 | |||||
5548 | return true; | ||||
5549 | } | ||||
5550 | |||||
5551 | bool updateWithLoad(Attributor &A, LoadInst &L) { | ||||
5552 | auto Union = [&](Value &V) { | ||||
5553 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||
5554 | SimplifiedAssociatedValue, &V, L.getType()); | ||||
5555 | return SimplifiedAssociatedValue != Optional<Value *>(nullptr); | ||||
5556 | }; | ||||
5557 | return handleLoad(A, *this, L, Union); | ||||
5558 | } | ||||
5559 | |||||
5560 | /// Use the generic, non-optimistic InstSimplfy functionality if we managed to | ||||
5561 | /// simplify any operand of the instruction \p I. Return true if successful, | ||||
5562 | /// in that case SimplifiedAssociatedValue will be updated. | ||||
5563 | bool handleGenericInst(Attributor &A, Instruction &I) { | ||||
5564 | bool SomeSimplified = false; | ||||
5565 | bool UsedAssumedInformation = false; | ||||
5566 | |||||
5567 | SmallVector<Value *, 8> NewOps(I.getNumOperands()); | ||||
5568 | int Idx = 0; | ||||
5569 | for (Value *Op : I.operands()) { | ||||
5570 | const auto &SimplifiedOp = | ||||
5571 | A.getAssumedSimplified(IRPosition::value(*Op, getCallBaseContext()), | ||||
5572 | *this, UsedAssumedInformation); | ||||
5573 | // If we are not sure about any operand we are not sure about the entire | ||||
5574 | // instruction, we'll wait. | ||||
5575 | if (!SimplifiedOp.hasValue()) | ||||
5576 | return true; | ||||
5577 | |||||
5578 | if (SimplifiedOp.getValue()) | ||||
5579 | NewOps[Idx] = SimplifiedOp.getValue(); | ||||
5580 | else | ||||
5581 | NewOps[Idx] = Op; | ||||
5582 | |||||
5583 | SomeSimplified |= (NewOps[Idx] != Op); | ||||
5584 | ++Idx; | ||||
5585 | } | ||||
5586 | |||||
5587 | // We won't bother with the InstSimplify interface if we didn't simplify any | ||||
5588 | // operand ourselves. | ||||
5589 | if (!SomeSimplified) | ||||
5590 | return false; | ||||
5591 | |||||
5592 | InformationCache &InfoCache = A.getInfoCache(); | ||||
5593 | Function *F = I.getFunction(); | ||||
5594 | const auto *DT = | ||||
5595 | InfoCache.getAnalysisResultForFunction<DominatorTreeAnalysis>(*F); | ||||
5596 | const auto *TLI = A.getInfoCache().getTargetLibraryInfoForFunction(*F); | ||||
5597 | auto *AC = InfoCache.getAnalysisResultForFunction<AssumptionAnalysis>(*F); | ||||
5598 | OptimizationRemarkEmitter *ORE = nullptr; | ||||
5599 | |||||
5600 | const DataLayout &DL = I.getModule()->getDataLayout(); | ||||
5601 | SimplifyQuery Q(DL, TLI, DT, AC, &I); | ||||
5602 | if (Value *SimplifiedI = | ||||
5603 | SimplifyInstructionWithOperands(&I, NewOps, Q, ORE)) { | ||||
5604 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||
5605 | SimplifiedAssociatedValue, SimplifiedI, I.getType()); | ||||
5606 | return SimplifiedAssociatedValue != Optional<Value *>(nullptr); | ||||
5607 | } | ||||
5608 | return false; | ||||
5609 | } | ||||
5610 | |||||
5611 | /// See AbstractAttribute::updateImpl(...). | ||||
5612 | ChangeStatus updateImpl(Attributor &A) override { | ||||
5613 | auto Before = SimplifiedAssociatedValue; | ||||
5614 | |||||
5615 | auto VisitValueCB = [&](Value &V, const Instruction *CtxI, bool &, | ||||
5616 | bool Stripped) -> bool { | ||||
5617 | auto &AA = A.getAAFor<AAValueSimplify>( | ||||
5618 | *this, IRPosition::value(V, getCallBaseContext()), | ||||
5619 | DepClassTy::REQUIRED); | ||||
5620 | if (!Stripped && this == &AA) { | ||||
5621 | |||||
5622 | if (auto *I = dyn_cast<Instruction>(&V)) { | ||||
5623 | if (auto *LI = dyn_cast<LoadInst>(&V)) | ||||
5624 | if (updateWithLoad(A, *LI)) | ||||
5625 | return true; | ||||
5626 | if (auto *Cmp = dyn_cast<CmpInst>(&V)) | ||||
5627 | if (handleCmp(A, *Cmp)) | ||||
5628 | return true; | ||||
5629 | if (handleGenericInst(A, *I)) | ||||
5630 | return true; | ||||
5631 | } | ||||
5632 | // TODO: Look the instruction and check recursively. | ||||
5633 | |||||
5634 | LLVM_DEBUG(dbgs() << "[ValueSimplify] Can't be stripped more : " << Vdo { } while (false) | ||||
5635 | << "\n")do { } while (false); | ||||
5636 | return false; | ||||
5637 | } | ||||
5638 | return checkAndUpdate(A, *this, | ||||
5639 | IRPosition::value(V, getCallBaseContext())); | ||||
5640 | }; | ||||
5641 | |||||
5642 | bool Dummy = false; | ||||
5643 | if (!genericValueTraversal<bool>(A, getIRPosition(), *this, Dummy, | ||||
5644 | VisitValueCB, getCtxI(), | ||||
5645 | /* UseValueSimplify */ false)) | ||||
5646 | if (!askSimplifiedValueForOtherAAs(A)) | ||||
5647 | return indicatePessimisticFixpoint(); | ||||
5648 | |||||
5649 | // If a candicate was found in this update, return CHANGED. | ||||
5650 | return Before == SimplifiedAssociatedValue ? ChangeStatus::UNCHANGED | ||||
5651 | : ChangeStatus ::CHANGED; | ||||
5652 | } | ||||
5653 | |||||
5654 | /// See AbstractAttribute::trackStatistics() | ||||
5655 | void trackStatistics() const override { | ||||
5656 | STATS_DECLTRACK_FLOATING_ATTR(value_simplify){ static llvm::Statistic NumIRFloating_value_simplify = {"attributor" , "NumIRFloating_value_simplify", ("Number of floating values known to be '" "value_simplify" "'")};; ++(NumIRFloating_value_simplify); } | ||||
5657 | } | ||||
5658 | }; | ||||
5659 | |||||
5660 | struct AAValueSimplifyFunction : AAValueSimplifyImpl { | ||||
5661 | AAValueSimplifyFunction(const IRPosition &IRP, Attributor &A) | ||||
5662 | : AAValueSimplifyImpl(IRP, A) {} | ||||
5663 | |||||
5664 | /// See AbstractAttribute::initialize(...). | ||||
5665 | void initialize(Attributor &A) override { | ||||
5666 | SimplifiedAssociatedValue = nullptr; | ||||
5667 | indicateOptimisticFixpoint(); | ||||
5668 | } | ||||
5669 | /// See AbstractAttribute::initialize(...). | ||||
5670 | ChangeStatus updateImpl(Attributor &A) override { | ||||
5671 | llvm_unreachable(__builtin_unreachable() | ||||
5672 | "AAValueSimplify(Function|CallSite)::updateImpl will not be called")__builtin_unreachable(); | ||||
5673 | } | ||||
5674 | /// See AbstractAttribute::trackStatistics() | ||||
5675 | void trackStatistics() const override { | ||||
5676 | STATS_DECLTRACK_FN_ATTR(value_simplify){ static llvm::Statistic NumIRFunction_value_simplify = {"attributor" , "NumIRFunction_value_simplify", ("Number of " "functions" " marked '" "value_simplify" "'")};; ++(NumIRFunction_value_simplify); } | ||||
5677 | } | ||||
5678 | }; | ||||
5679 | |||||
5680 | struct AAValueSimplifyCallSite : AAValueSimplifyFunction { | ||||
5681 | AAValueSimplifyCallSite(const IRPosition &IRP, Attributor &A) | ||||
5682 | : AAValueSimplifyFunction(IRP, A) {} | ||||
5683 | /// See AbstractAttribute::trackStatistics() | ||||
5684 | void trackStatistics() const override { | ||||
5685 | STATS_DECLTRACK_CS_ATTR(value_simplify){ static llvm::Statistic NumIRCS_value_simplify = {"attributor" , "NumIRCS_value_simplify", ("Number of " "call site" " marked '" "value_simplify" "'")};; ++(NumIRCS_value_simplify); } | ||||
5686 | } | ||||
5687 | }; | ||||
5688 | |||||
5689 | struct AAValueSimplifyCallSiteReturned : AAValueSimplifyImpl { | ||||
5690 | AAValueSimplifyCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
5691 | : AAValueSimplifyImpl(IRP, A) {} | ||||
5692 | |||||
5693 | void initialize(Attributor &A) override { | ||||
5694 | AAValueSimplifyImpl::initialize(A); | ||||
5695 | if (!getAssociatedFunction()) | ||||
5696 | indicatePessimisticFixpoint(); | ||||
5697 | } | ||||
5698 | |||||
5699 | /// See AbstractAttribute::updateImpl(...). | ||||
5700 | ChangeStatus updateImpl(Attributor &A) override { | ||||
5701 | auto Before = SimplifiedAssociatedValue; | ||||
5702 | auto &RetAA = A.getAAFor<AAReturnedValues>( | ||||
5703 | *this, IRPosition::function(*getAssociatedFunction()), | ||||
5704 | DepClassTy::REQUIRED); | ||||
5705 | auto PredForReturned = | ||||
5706 | [&](Value &RetVal, const SmallSetVector<ReturnInst *, 4> &RetInsts) { | ||||
5707 | bool UsedAssumedInformation = false; | ||||
5708 | Optional<Value *> CSRetVal = A.translateArgumentToCallSiteContent( | ||||
5709 | &RetVal, *cast<CallBase>(getCtxI()), *this, | ||||
5710 | UsedAssumedInformation); | ||||
5711 | SimplifiedAssociatedValue = AA::combineOptionalValuesInAAValueLatice( | ||||
5712 | SimplifiedAssociatedValue, CSRetVal, getAssociatedType()); | ||||
5713 | return SimplifiedAssociatedValue != Optional<Value *>(nullptr); | ||||
5714 | }; | ||||
5715 | if (!RetAA.checkForAllReturnedValuesAndReturnInsts(PredForReturned)) | ||||
5716 | if (!askSimplifiedValueForOtherAAs(A)) | ||||
5717 | return indicatePessimisticFixpoint(); | ||||
5718 | return Before == SimplifiedAssociatedValue ? ChangeStatus::UNCHANGED | ||||
5719 | : ChangeStatus ::CHANGED; | ||||
5720 | } | ||||
5721 | |||||
5722 | void trackStatistics() const override { | ||||
5723 | STATS_DECLTRACK_CSRET_ATTR(value_simplify){ static llvm::Statistic NumIRCSReturn_value_simplify = {"attributor" , "NumIRCSReturn_value_simplify", ("Number of " "call site returns" " marked '" "value_simplify" "'")};; ++(NumIRCSReturn_value_simplify ); } | ||||
5724 | } | ||||
5725 | }; | ||||
5726 | |||||
5727 | struct AAValueSimplifyCallSiteArgument : AAValueSimplifyFloating { | ||||
5728 | AAValueSimplifyCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
5729 | : AAValueSimplifyFloating(IRP, A) {} | ||||
5730 | |||||
5731 | /// See AbstractAttribute::manifest(...). | ||||
5732 | ChangeStatus manifest(Attributor &A) override { | ||||
5733 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
5734 | |||||
5735 | if (auto *NewV = getReplacementValue(A)) { | ||||
5736 | Use &U = cast<CallBase>(&getAnchorValue()) | ||||
5737 | ->getArgOperandUse(getCallSiteArgNo()); | ||||
5738 | if (A.changeUseAfterManifest(U, *NewV)) | ||||
5739 | Changed = ChangeStatus::CHANGED; | ||||
5740 | } | ||||
5741 | |||||
5742 | return Changed | AAValueSimplify::manifest(A); | ||||
5743 | } | ||||
5744 | |||||
5745 | void trackStatistics() const override { | ||||
5746 | STATS_DECLTRACK_CSARG_ATTR(value_simplify){ static llvm::Statistic NumIRCSArguments_value_simplify = {"attributor" , "NumIRCSArguments_value_simplify", ("Number of " "call site arguments" " marked '" "value_simplify" "'")};; ++(NumIRCSArguments_value_simplify ); } | ||||
5747 | } | ||||
5748 | }; | ||||
5749 | |||||
5750 | /// ----------------------- Heap-To-Stack Conversion --------------------------- | ||||
5751 | struct AAHeapToStackFunction final : public AAHeapToStack { | ||||
5752 | |||||
5753 | struct AllocationInfo { | ||||
5754 | /// The call that allocates the memory. | ||||
5755 | CallBase *const CB; | ||||
5756 | |||||
5757 | /// The kind of allocation. | ||||
5758 | const enum class AllocationKind { | ||||
5759 | MALLOC, | ||||
5760 | CALLOC, | ||||
5761 | ALIGNED_ALLOC, | ||||
5762 | } Kind; | ||||
5763 | |||||
5764 | /// The library function id for the allocation. | ||||
5765 | LibFunc LibraryFunctionId = NotLibFunc; | ||||
5766 | |||||
5767 | /// The status wrt. a rewrite. | ||||
5768 | enum { | ||||
5769 | STACK_DUE_TO_USE, | ||||
5770 | STACK_DUE_TO_FREE, | ||||
5771 | INVALID, | ||||
5772 | } Status = STACK_DUE_TO_USE; | ||||
5773 | |||||
5774 | /// Flag to indicate if we encountered a use that might free this allocation | ||||
5775 | /// but which is not in the deallocation infos. | ||||
5776 | bool HasPotentiallyFreeingUnknownUses = false; | ||||
5777 | |||||
5778 | /// The set of free calls that use this allocation. | ||||
5779 | SmallPtrSet<CallBase *, 1> PotentialFreeCalls{}; | ||||
5780 | }; | ||||
5781 | |||||
5782 | struct DeallocationInfo { | ||||
5783 | /// The call that deallocates the memory. | ||||
5784 | CallBase *const CB; | ||||
5785 | |||||
5786 | /// Flag to indicate if we don't know all objects this deallocation might | ||||
5787 | /// free. | ||||
5788 | bool MightFreeUnknownObjects = false; | ||||
5789 | |||||
5790 | /// The set of allocation calls that are potentially freed. | ||||
5791 | SmallPtrSet<CallBase *, 1> PotentialAllocationCalls{}; | ||||
5792 | }; | ||||
5793 | |||||
5794 | AAHeapToStackFunction(const IRPosition &IRP, Attributor &A) | ||||
5795 | : AAHeapToStack(IRP, A) {} | ||||
5796 | |||||
5797 | ~AAHeapToStackFunction() { | ||||
5798 | // Ensure we call the destructor so we release any memory allocated in the | ||||
5799 | // sets. | ||||
5800 | for (auto &It : AllocationInfos) | ||||
5801 | It.getSecond()->~AllocationInfo(); | ||||
5802 | for (auto &It : DeallocationInfos) | ||||
5803 | It.getSecond()->~DeallocationInfo(); | ||||
5804 | } | ||||
5805 | |||||
5806 | void initialize(Attributor &A) override { | ||||
5807 | AAHeapToStack::initialize(A); | ||||
5808 | |||||
5809 | const Function *F = getAnchorScope(); | ||||
5810 | const auto *TLI = A.getInfoCache().getTargetLibraryInfoForFunction(*F); | ||||
5811 | |||||
5812 | auto AllocationIdentifierCB = [&](Instruction &I) { | ||||
5813 | CallBase *CB = dyn_cast<CallBase>(&I); | ||||
5814 | if (!CB) | ||||
5815 | return true; | ||||
5816 | if (isFreeCall(CB, TLI)) { | ||||
5817 | DeallocationInfos[CB] = new (A.Allocator) DeallocationInfo{CB}; | ||||
5818 | return true; | ||||
5819 | } | ||||
5820 | bool IsMalloc = isMallocLikeFn(CB, TLI); | ||||
5821 | bool IsAlignedAllocLike = !IsMalloc && isAlignedAllocLikeFn(CB, TLI); | ||||
5822 | bool IsCalloc = | ||||
5823 | !IsMalloc && !IsAlignedAllocLike && isCallocLikeFn(CB, TLI); | ||||
5824 | if (!IsMalloc && !IsAlignedAllocLike && !IsCalloc) | ||||
5825 | return true; | ||||
5826 | auto Kind = | ||||
5827 | IsMalloc ? AllocationInfo::AllocationKind::MALLOC | ||||
5828 | : (IsCalloc ? AllocationInfo::AllocationKind::CALLOC | ||||
5829 | : AllocationInfo::AllocationKind::ALIGNED_ALLOC); | ||||
5830 | |||||
5831 | AllocationInfo *AI = new (A.Allocator) AllocationInfo{CB, Kind}; | ||||
5832 | AllocationInfos[CB] = AI; | ||||
5833 | TLI->getLibFunc(*CB, AI->LibraryFunctionId); | ||||
5834 | return true; | ||||
5835 | }; | ||||
5836 | |||||
5837 | bool UsedAssumedInformation = false; | ||||
5838 | bool Success = A.checkForAllCallLikeInstructions( | ||||
5839 | AllocationIdentifierCB, *this, UsedAssumedInformation, | ||||
5840 | /* CheckBBLivenessOnly */ false, | ||||
5841 | /* CheckPotentiallyDead */ true); | ||||
5842 | (void)Success; | ||||
5843 | assert(Success && "Did not expect the call base visit callback to fail!")(static_cast<void> (0)); | ||||
5844 | } | ||||
5845 | |||||
5846 | const std::string getAsStr() const override { | ||||
5847 | unsigned NumH2SMallocs = 0, NumInvalidMallocs = 0; | ||||
5848 | for (const auto &It : AllocationInfos) { | ||||
5849 | if (It.second->Status == AllocationInfo::INVALID) | ||||
5850 | ++NumInvalidMallocs; | ||||
5851 | else | ||||
5852 | ++NumH2SMallocs; | ||||
5853 | } | ||||
5854 | return "[H2S] Mallocs Good/Bad: " + std::to_string(NumH2SMallocs) + "/" + | ||||
5855 | std::to_string(NumInvalidMallocs); | ||||
5856 | } | ||||
5857 | |||||
5858 | /// See AbstractAttribute::trackStatistics(). | ||||
5859 | void trackStatistics() const override { | ||||
5860 | STATS_DECL(static llvm::Statistic NumIRFunction_MallocCalls = {"attributor" , "NumIRFunction_MallocCalls", "Number of malloc/calloc/aligned_alloc calls converted to allocas" };; | ||||
5861 | MallocCalls, Function,static llvm::Statistic NumIRFunction_MallocCalls = {"attributor" , "NumIRFunction_MallocCalls", "Number of malloc/calloc/aligned_alloc calls converted to allocas" };; | ||||
5862 | "Number of malloc/calloc/aligned_alloc calls converted to allocas")static llvm::Statistic NumIRFunction_MallocCalls = {"attributor" , "NumIRFunction_MallocCalls", "Number of malloc/calloc/aligned_alloc calls converted to allocas" };;; | ||||
5863 | for (auto &It : AllocationInfos) | ||||
5864 | if (It.second->Status != AllocationInfo::INVALID) | ||||
5865 | ++BUILD_STAT_NAME(MallocCalls, Function)NumIRFunction_MallocCalls; | ||||
5866 | } | ||||
5867 | |||||
5868 | bool isAssumedHeapToStack(const CallBase &CB) const override { | ||||
5869 | if (isValidState()) | ||||
5870 | if (AllocationInfo *AI = AllocationInfos.lookup(&CB)) | ||||
5871 | return AI->Status != AllocationInfo::INVALID; | ||||
5872 | return false; | ||||
5873 | } | ||||
5874 | |||||
5875 | bool isAssumedHeapToStackRemovedFree(CallBase &CB) const override { | ||||
5876 | if (!isValidState()) | ||||
5877 | return false; | ||||
5878 | |||||
5879 | for (auto &It : AllocationInfos) { | ||||
5880 | AllocationInfo &AI = *It.second; | ||||
5881 | if (AI.Status == AllocationInfo::INVALID) | ||||
5882 | continue; | ||||
5883 | |||||
5884 | if (AI.PotentialFreeCalls.count(&CB)) | ||||
5885 | return true; | ||||
5886 | } | ||||
5887 | |||||
5888 | return false; | ||||
5889 | } | ||||
5890 | |||||
5891 | ChangeStatus manifest(Attributor &A) override { | ||||
5892 | assert(getState().isValidState() &&(static_cast<void> (0)) | ||||
5893 | "Attempted to manifest an invalid state!")(static_cast<void> (0)); | ||||
5894 | |||||
5895 | ChangeStatus HasChanged = ChangeStatus::UNCHANGED; | ||||
5896 | Function *F = getAnchorScope(); | ||||
5897 | const auto *TLI = A.getInfoCache().getTargetLibraryInfoForFunction(*F); | ||||
5898 | |||||
5899 | for (auto &It : AllocationInfos) { | ||||
5900 | AllocationInfo &AI = *It.second; | ||||
5901 | if (AI.Status == AllocationInfo::INVALID) | ||||
5902 | continue; | ||||
5903 | |||||
5904 | for (CallBase *FreeCall : AI.PotentialFreeCalls) { | ||||
5905 | LLVM_DEBUG(dbgs() << "H2S: Removing free call: " << *FreeCall << "\n")do { } while (false); | ||||
5906 | A.deleteAfterManifest(*FreeCall); | ||||
5907 | HasChanged = ChangeStatus::CHANGED; | ||||
5908 | } | ||||
5909 | |||||
5910 | LLVM_DEBUG(dbgs() << "H2S: Removing malloc-like call: " << *AI.CBdo { } while (false) | ||||
5911 | << "\n")do { } while (false); | ||||
5912 | |||||
5913 | auto Remark = [&](OptimizationRemark OR) { | ||||
5914 | LibFunc IsAllocShared; | ||||
5915 | if (TLI->getLibFunc(*AI.CB, IsAllocShared)) | ||||
5916 | if (IsAllocShared == LibFunc___kmpc_alloc_shared) | ||||
5917 | return OR << "Moving globalized variable to the stack."; | ||||
5918 | return OR << "Moving memory allocation from the heap to the stack."; | ||||
5919 | }; | ||||
5920 | if (AI.LibraryFunctionId == LibFunc___kmpc_alloc_shared) | ||||
5921 | A.emitRemark<OptimizationRemark>(AI.CB, "OMP110", Remark); | ||||
5922 | else | ||||
5923 | A.emitRemark<OptimizationRemark>(AI.CB, "HeapToStack", Remark); | ||||
5924 | |||||
5925 | Value *Size; | ||||
5926 | Optional<APInt> SizeAPI = getSize(A, *this, AI); | ||||
5927 | if (SizeAPI.hasValue()) { | ||||
5928 | Size = ConstantInt::get(AI.CB->getContext(), *SizeAPI); | ||||
5929 | } else if (AI.Kind == AllocationInfo::AllocationKind::CALLOC) { | ||||
5930 | auto *Num = AI.CB->getOperand(0); | ||||
5931 | auto *SizeT = AI.CB->getOperand(1); | ||||
5932 | IRBuilder<> B(AI.CB); | ||||
5933 | Size = B.CreateMul(Num, SizeT, "h2s.calloc.size"); | ||||
5934 | } else if (AI.Kind == AllocationInfo::AllocationKind::ALIGNED_ALLOC) { | ||||
5935 | Size = AI.CB->getOperand(1); | ||||
5936 | } else { | ||||
5937 | Size = AI.CB->getOperand(0); | ||||
5938 | } | ||||
5939 | |||||
5940 | Align Alignment(1); | ||||
5941 | if (AI.Kind == AllocationInfo::AllocationKind::ALIGNED_ALLOC) { | ||||
5942 | Optional<APInt> AlignmentAPI = | ||||
5943 | getAPInt(A, *this, *AI.CB->getArgOperand(0)); | ||||
5944 | assert(AlignmentAPI.hasValue() &&(static_cast<void> (0)) | ||||
5945 | "Expected an alignment during manifest!")(static_cast<void> (0)); | ||||
5946 | Alignment = | ||||
5947 | max(Alignment, MaybeAlign(AlignmentAPI.getValue().getZExtValue())); | ||||
5948 | } | ||||
5949 | |||||
5950 | unsigned AS = cast<PointerType>(AI.CB->getType())->getAddressSpace(); | ||||
5951 | Instruction *Alloca = | ||||
5952 | new AllocaInst(Type::getInt8Ty(F->getContext()), AS, Size, Alignment, | ||||
5953 | "", AI.CB->getNextNode()); | ||||
5954 | |||||
5955 | if (Alloca->getType() != AI.CB->getType()) | ||||
5956 | Alloca = new BitCastInst(Alloca, AI.CB->getType(), "malloc_bc", | ||||
5957 | Alloca->getNextNode()); | ||||
5958 | |||||
5959 | A.changeValueAfterManifest(*AI.CB, *Alloca); | ||||
5960 | |||||
5961 | if (auto *II = dyn_cast<InvokeInst>(AI.CB)) { | ||||
5962 | auto *NBB = II->getNormalDest(); | ||||
5963 | BranchInst::Create(NBB, AI.CB->getParent()); | ||||
5964 | A.deleteAfterManifest(*AI.CB); | ||||
5965 | } else { | ||||
5966 | A.deleteAfterManifest(*AI.CB); | ||||
5967 | } | ||||
5968 | |||||
5969 | // Zero out the allocated memory if it was a calloc. | ||||
5970 | if (AI.Kind == AllocationInfo::AllocationKind::CALLOC) { | ||||
5971 | auto *BI = new BitCastInst(Alloca, AI.CB->getType(), "calloc_bc", | ||||
5972 | Alloca->getNextNode()); | ||||
5973 | Value *Ops[] = { | ||||
5974 | BI, ConstantInt::get(F->getContext(), APInt(8, 0, false)), Size, | ||||
5975 | ConstantInt::get(Type::getInt1Ty(F->getContext()), false)}; | ||||
5976 | |||||
5977 | Type *Tys[] = {BI->getType(), AI.CB->getOperand(0)->getType()}; | ||||
5978 | Module *M = F->getParent(); | ||||
5979 | Function *Fn = Intrinsic::getDeclaration(M, Intrinsic::memset, Tys); | ||||
5980 | CallInst::Create(Fn, Ops, "", BI->getNextNode()); | ||||
5981 | } | ||||
5982 | HasChanged = ChangeStatus::CHANGED; | ||||
5983 | } | ||||
5984 | |||||
5985 | return HasChanged; | ||||
5986 | } | ||||
5987 | |||||
5988 | Optional<APInt> getAPInt(Attributor &A, const AbstractAttribute &AA, | ||||
5989 | Value &V) { | ||||
5990 | bool UsedAssumedInformation = false; | ||||
5991 | Optional<Constant *> SimpleV = | ||||
5992 | A.getAssumedConstant(V, AA, UsedAssumedInformation); | ||||
5993 | if (!SimpleV.hasValue()) | ||||
5994 | return APInt(64, 0); | ||||
5995 | if (auto *CI = dyn_cast_or_null<ConstantInt>(SimpleV.getValue())) | ||||
5996 | return CI->getValue(); | ||||
5997 | return llvm::None; | ||||
5998 | } | ||||
5999 | |||||
6000 | Optional<APInt> getSize(Attributor &A, const AbstractAttribute &AA, | ||||
6001 | AllocationInfo &AI) { | ||||
6002 | |||||
6003 | if (AI.Kind == AllocationInfo::AllocationKind::MALLOC) | ||||
6004 | return getAPInt(A, AA, *AI.CB->getArgOperand(0)); | ||||
6005 | |||||
6006 | if (AI.Kind == AllocationInfo::AllocationKind::ALIGNED_ALLOC) | ||||
6007 | // Only if the alignment is also constant we return a size. | ||||
6008 | return getAPInt(A, AA, *AI.CB->getArgOperand(0)).hasValue() | ||||
6009 | ? getAPInt(A, AA, *AI.CB->getArgOperand(1)) | ||||
6010 | : llvm::None; | ||||
6011 | |||||
6012 | assert(AI.Kind == AllocationInfo::AllocationKind::CALLOC &&(static_cast<void> (0)) | ||||
6013 | "Expected only callocs are left")(static_cast<void> (0)); | ||||
6014 | Optional<APInt> Num = getAPInt(A, AA, *AI.CB->getArgOperand(0)); | ||||
6015 | Optional<APInt> Size = getAPInt(A, AA, *AI.CB->getArgOperand(1)); | ||||
6016 | if (!Num.hasValue() || !Size.hasValue()) | ||||
6017 | return llvm::None; | ||||
6018 | bool Overflow = false; | ||||
6019 | Size = Size.getValue().umul_ov(Num.getValue(), Overflow); | ||||
6020 | return Overflow ? llvm::None : Size; | ||||
6021 | } | ||||
6022 | |||||
6023 | /// Collection of all malloc-like calls in a function with associated | ||||
6024 | /// information. | ||||
6025 | DenseMap<CallBase *, AllocationInfo *> AllocationInfos; | ||||
6026 | |||||
6027 | /// Collection of all free-like calls in a function with associated | ||||
6028 | /// information. | ||||
6029 | DenseMap<CallBase *, DeallocationInfo *> DeallocationInfos; | ||||
6030 | |||||
6031 | ChangeStatus updateImpl(Attributor &A) override; | ||||
6032 | }; | ||||
6033 | |||||
6034 | ChangeStatus AAHeapToStackFunction::updateImpl(Attributor &A) { | ||||
6035 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
6036 | const Function *F = getAnchorScope(); | ||||
6037 | |||||
6038 | const auto &LivenessAA = | ||||
6039 | A.getAAFor<AAIsDead>(*this, IRPosition::function(*F), DepClassTy::NONE); | ||||
6040 | |||||
6041 | MustBeExecutedContextExplorer &Explorer = | ||||
6042 | A.getInfoCache().getMustBeExecutedContextExplorer(); | ||||
6043 | |||||
6044 | bool StackIsAccessibleByOtherThreads = | ||||
6045 | A.getInfoCache().stackIsAccessibleByOtherThreads(); | ||||
6046 | |||||
6047 | // Flag to ensure we update our deallocation information at most once per | ||||
6048 | // updateImpl call and only if we use the free check reasoning. | ||||
6049 | bool HasUpdatedFrees = false; | ||||
6050 | |||||
6051 | auto UpdateFrees = [&]() { | ||||
6052 | HasUpdatedFrees = true; | ||||
6053 | |||||
6054 | for (auto &It : DeallocationInfos) { | ||||
6055 | DeallocationInfo &DI = *It.second; | ||||
6056 | // For now we cannot use deallocations that have unknown inputs, skip | ||||
6057 | // them. | ||||
6058 | if (DI.MightFreeUnknownObjects) | ||||
6059 | continue; | ||||
6060 | |||||
6061 | // No need to analyze dead calls, ignore them instead. | ||||
6062 | bool UsedAssumedInformation = false; | ||||
6063 | if (A.isAssumedDead(*DI.CB, this, &LivenessAA, UsedAssumedInformation, | ||||
6064 | /* CheckBBLivenessOnly */ true)) | ||||
6065 | continue; | ||||
6066 | |||||
6067 | // Use the optimistic version to get the freed objects, ignoring dead | ||||
6068 | // branches etc. | ||||
6069 | SmallVector<Value *, 8> Objects; | ||||
6070 | if (!AA::getAssumedUnderlyingObjects(A, *DI.CB->getArgOperand(0), Objects, | ||||
6071 | *this, DI.CB)) { | ||||
6072 | LLVM_DEBUG(do { } while (false) | ||||
6073 | dbgs()do { } while (false) | ||||
6074 | << "[H2S] Unexpected failure in getAssumedUnderlyingObjects!\n")do { } while (false); | ||||
6075 | DI.MightFreeUnknownObjects = true; | ||||
6076 | continue; | ||||
6077 | } | ||||
6078 | |||||
6079 | // Check each object explicitly. | ||||
6080 | for (auto *Obj : Objects) { | ||||
6081 | // Free of null and undef can be ignored as no-ops (or UB in the latter | ||||
6082 | // case). | ||||
6083 | if (isa<ConstantPointerNull>(Obj) || isa<UndefValue>(Obj)) | ||||
6084 | continue; | ||||
6085 | |||||
6086 | CallBase *ObjCB = dyn_cast<CallBase>(Obj); | ||||
6087 | if (!ObjCB) { | ||||
6088 | LLVM_DEBUG(dbgs()do { } while (false) | ||||
6089 | << "[H2S] Free of a non-call object: " << *Obj << "\n")do { } while (false); | ||||
6090 | DI.MightFreeUnknownObjects = true; | ||||
6091 | continue; | ||||
6092 | } | ||||
6093 | |||||
6094 | AllocationInfo *AI = AllocationInfos.lookup(ObjCB); | ||||
6095 | if (!AI) { | ||||
6096 | LLVM_DEBUG(dbgs() << "[H2S] Free of a non-allocation object: " << *Objdo { } while (false) | ||||
6097 | << "\n")do { } while (false); | ||||
6098 | DI.MightFreeUnknownObjects = true; | ||||
6099 | continue; | ||||
6100 | } | ||||
6101 | |||||
6102 | DI.PotentialAllocationCalls.insert(ObjCB); | ||||
6103 | } | ||||
6104 | } | ||||
6105 | }; | ||||
6106 | |||||
6107 | auto FreeCheck = [&](AllocationInfo &AI) { | ||||
6108 | // If the stack is not accessible by other threads, the "must-free" logic | ||||
6109 | // doesn't apply as the pointer could be shared and needs to be places in | ||||
6110 | // "shareable" memory. | ||||
6111 | if (!StackIsAccessibleByOtherThreads) { | ||||
6112 | auto &NoSyncAA = | ||||
6113 | A.getAAFor<AANoSync>(*this, getIRPosition(), DepClassTy::OPTIONAL); | ||||
6114 | if (!NoSyncAA.isAssumedNoSync()) { | ||||
6115 | LLVM_DEBUG(do { } while (false) | ||||
6116 | dbgs() << "[H2S] found an escaping use, stack is not accessible by "do { } while (false) | ||||
6117 | "other threads and function is not nosync:\n")do { } while (false); | ||||
6118 | return false; | ||||
6119 | } | ||||
6120 | } | ||||
6121 | if (!HasUpdatedFrees) | ||||
6122 | UpdateFrees(); | ||||
6123 | |||||
6124 | // TODO: Allow multi exit functions that have different free calls. | ||||
6125 | if (AI.PotentialFreeCalls.size() != 1) { | ||||
6126 | LLVM_DEBUG(dbgs() << "[H2S] did not find one free call but "do { } while (false) | ||||
6127 | << AI.PotentialFreeCalls.size() << "\n")do { } while (false); | ||||
6128 | return false; | ||||
6129 | } | ||||
6130 | CallBase *UniqueFree = *AI.PotentialFreeCalls.begin(); | ||||
6131 | DeallocationInfo *DI = DeallocationInfos.lookup(UniqueFree); | ||||
6132 | if (!DI) { | ||||
6133 | LLVM_DEBUG(do { } while (false) | ||||
6134 | dbgs() << "[H2S] unique free call was not known as deallocation call "do { } while (false) | ||||
6135 | << *UniqueFree << "\n")do { } while (false); | ||||
6136 | return false; | ||||
6137 | } | ||||
6138 | if (DI->MightFreeUnknownObjects) { | ||||
6139 | LLVM_DEBUG(do { } while (false) | ||||
6140 | dbgs() << "[H2S] unique free call might free unknown allocations\n")do { } while (false); | ||||
6141 | return false; | ||||
6142 | } | ||||
6143 | if (DI->PotentialAllocationCalls.size() > 1) { | ||||
6144 | LLVM_DEBUG(dbgs() << "[H2S] unique free call might free "do { } while (false) | ||||
6145 | << DI->PotentialAllocationCalls.size()do { } while (false) | ||||
6146 | << " different allocations\n")do { } while (false); | ||||
6147 | return false; | ||||
6148 | } | ||||
6149 | if (*DI->PotentialAllocationCalls.begin() != AI.CB) { | ||||
6150 | LLVM_DEBUG(do { } while (false) | ||||
6151 | dbgs()do { } while (false) | ||||
6152 | << "[H2S] unique free call not known to free this allocation but "do { } while (false) | ||||
6153 | << **DI->PotentialAllocationCalls.begin() << "\n")do { } while (false); | ||||
6154 | return false; | ||||
6155 | } | ||||
6156 | Instruction *CtxI = isa<InvokeInst>(AI.CB) ? AI.CB : AI.CB->getNextNode(); | ||||
6157 | if (!Explorer.findInContextOf(UniqueFree, CtxI)) { | ||||
6158 | LLVM_DEBUG(do { } while (false) | ||||
6159 | dbgs()do { } while (false) | ||||
6160 | << "[H2S] unique free call might not be executed with the allocation "do { } while (false) | ||||
6161 | << *UniqueFree << "\n")do { } while (false); | ||||
6162 | return false; | ||||
6163 | } | ||||
6164 | return true; | ||||
6165 | }; | ||||
6166 | |||||
6167 | auto UsesCheck = [&](AllocationInfo &AI) { | ||||
6168 | bool ValidUsesOnly = true; | ||||
6169 | |||||
6170 | auto Pred = [&](const Use &U, bool &Follow) -> bool { | ||||
6171 | Instruction *UserI = cast<Instruction>(U.getUser()); | ||||
6172 | if (isa<LoadInst>(UserI)) | ||||
6173 | return true; | ||||
6174 | if (auto *SI = dyn_cast<StoreInst>(UserI)) { | ||||
6175 | if (SI->getValueOperand() == U.get()) { | ||||
6176 | LLVM_DEBUG(dbgs()do { } while (false) | ||||
6177 | << "[H2S] escaping store to memory: " << *UserI << "\n")do { } while (false); | ||||
6178 | ValidUsesOnly = false; | ||||
6179 | } else { | ||||
6180 | // A store into the malloc'ed memory is fine. | ||||
6181 | } | ||||
6182 | return true; | ||||
6183 | } | ||||
6184 | if (auto *CB = dyn_cast<CallBase>(UserI)) { | ||||
6185 | if (!CB->isArgOperand(&U) || CB->isLifetimeStartOrEnd()) | ||||
6186 | return true; | ||||
6187 | if (DeallocationInfos.count(CB)) { | ||||
6188 | AI.PotentialFreeCalls.insert(CB); | ||||
6189 | return true; | ||||
6190 | } | ||||
6191 | |||||
6192 | unsigned ArgNo = CB->getArgOperandNo(&U); | ||||
6193 | |||||
6194 | const auto &NoCaptureAA = A.getAAFor<AANoCapture>( | ||||
6195 | *this, IRPosition::callsite_argument(*CB, ArgNo), | ||||
6196 | DepClassTy::OPTIONAL); | ||||
6197 | |||||
6198 | // If a call site argument use is nofree, we are fine. | ||||
6199 | const auto &ArgNoFreeAA = A.getAAFor<AANoFree>( | ||||
6200 | *this, IRPosition::callsite_argument(*CB, ArgNo), | ||||
6201 | DepClassTy::OPTIONAL); | ||||
6202 | |||||
6203 | bool MaybeCaptured = !NoCaptureAA.isAssumedNoCapture(); | ||||
6204 | bool MaybeFreed = !ArgNoFreeAA.isAssumedNoFree(); | ||||
6205 | if (MaybeCaptured || | ||||
6206 | (AI.LibraryFunctionId != LibFunc___kmpc_alloc_shared && | ||||
6207 | MaybeFreed)) { | ||||
6208 | AI.HasPotentiallyFreeingUnknownUses |= MaybeFreed; | ||||
6209 | |||||
6210 | // Emit a missed remark if this is missed OpenMP globalization. | ||||
6211 | auto Remark = [&](OptimizationRemarkMissed ORM) { | ||||
6212 | return ORM | ||||
6213 | << "Could not move globalized variable to the stack. " | ||||
6214 | "Variable is potentially captured in call. Mark " | ||||
6215 | "parameter as `__attribute__((noescape))` to override."; | ||||
6216 | }; | ||||
6217 | |||||
6218 | if (ValidUsesOnly && | ||||
6219 | AI.LibraryFunctionId == LibFunc___kmpc_alloc_shared) | ||||
6220 | A.emitRemark<OptimizationRemarkMissed>(AI.CB, "OMP113", Remark); | ||||
6221 | |||||
6222 | LLVM_DEBUG(dbgs() << "[H2S] Bad user: " << *UserI << "\n")do { } while (false); | ||||
6223 | ValidUsesOnly = false; | ||||
6224 | } | ||||
6225 | return true; | ||||
6226 | } | ||||
6227 | |||||
6228 | if (isa<GetElementPtrInst>(UserI) || isa<BitCastInst>(UserI) || | ||||
6229 | isa<PHINode>(UserI) || isa<SelectInst>(UserI)) { | ||||
6230 | Follow = true; | ||||
6231 | return true; | ||||
6232 | } | ||||
6233 | // Unknown user for which we can not track uses further (in a way that | ||||
6234 | // makes sense). | ||||
6235 | LLVM_DEBUG(dbgs() << "[H2S] Unknown user: " << *UserI << "\n")do { } while (false); | ||||
6236 | ValidUsesOnly = false; | ||||
6237 | return true; | ||||
6238 | }; | ||||
6239 | if (!A.checkForAllUses(Pred, *this, *AI.CB)) | ||||
6240 | return false; | ||||
6241 | return ValidUsesOnly; | ||||
6242 | }; | ||||
6243 | |||||
6244 | // The actual update starts here. We look at all allocations and depending on | ||||
6245 | // their status perform the appropriate check(s). | ||||
6246 | for (auto &It : AllocationInfos) { | ||||
6247 | AllocationInfo &AI = *It.second; | ||||
6248 | if (AI.Status == AllocationInfo::INVALID) | ||||
6249 | continue; | ||||
6250 | |||||
6251 | if (MaxHeapToStackSize == -1) { | ||||
6252 | if (AI.Kind == AllocationInfo::AllocationKind::ALIGNED_ALLOC) | ||||
6253 | if (!getAPInt(A, *this, *AI.CB->getArgOperand(0)).hasValue()) { | ||||
6254 | LLVM_DEBUG(dbgs() << "[H2S] Unknown allocation alignment: " << *AI.CBdo { } while (false) | ||||
6255 | << "\n")do { } while (false); | ||||
6256 | AI.Status = AllocationInfo::INVALID; | ||||
6257 | Changed = ChangeStatus::CHANGED; | ||||
6258 | continue; | ||||
6259 | } | ||||
6260 | } else { | ||||
6261 | Optional<APInt> Size = getSize(A, *this, AI); | ||||
6262 | if (!Size.hasValue() || Size.getValue().ugt(MaxHeapToStackSize)) { | ||||
6263 | LLVM_DEBUG({do { } while (false) | ||||
6264 | if (!Size.hasValue())do { } while (false) | ||||
6265 | dbgs() << "[H2S] Unknown allocation size (or alignment): " << *AI.CBdo { } while (false) | ||||
6266 | << "\n";do { } while (false) | ||||
6267 | elsedo { } while (false) | ||||
6268 | dbgs() << "[H2S] Allocation size too large: " << *AI.CB << " vs. "do { } while (false) | ||||
6269 | << MaxHeapToStackSize << "\n";do { } while (false) | ||||
6270 | })do { } while (false); | ||||
6271 | |||||
6272 | AI.Status = AllocationInfo::INVALID; | ||||
6273 | Changed = ChangeStatus::CHANGED; | ||||
6274 | continue; | ||||
6275 | } | ||||
6276 | } | ||||
6277 | |||||
6278 | switch (AI.Status) { | ||||
6279 | case AllocationInfo::STACK_DUE_TO_USE: | ||||
6280 | if (UsesCheck(AI)) | ||||
6281 | continue; | ||||
6282 | AI.Status = AllocationInfo::STACK_DUE_TO_FREE; | ||||
6283 | LLVM_FALLTHROUGH[[gnu::fallthrough]]; | ||||
6284 | case AllocationInfo::STACK_DUE_TO_FREE: | ||||
6285 | if (FreeCheck(AI)) | ||||
6286 | continue; | ||||
6287 | AI.Status = AllocationInfo::INVALID; | ||||
6288 | Changed = ChangeStatus::CHANGED; | ||||
6289 | continue; | ||||
6290 | case AllocationInfo::INVALID: | ||||
6291 | llvm_unreachable("Invalid allocations should never reach this point!")__builtin_unreachable(); | ||||
6292 | }; | ||||
6293 | } | ||||
6294 | |||||
6295 | return Changed; | ||||
6296 | } | ||||
6297 | |||||
6298 | /// ----------------------- Privatizable Pointers ------------------------------ | ||||
6299 | struct AAPrivatizablePtrImpl : public AAPrivatizablePtr { | ||||
6300 | AAPrivatizablePtrImpl(const IRPosition &IRP, Attributor &A) | ||||
6301 | : AAPrivatizablePtr(IRP, A), PrivatizableType(llvm::None) {} | ||||
6302 | |||||
6303 | ChangeStatus indicatePessimisticFixpoint() override { | ||||
6304 | AAPrivatizablePtr::indicatePessimisticFixpoint(); | ||||
6305 | PrivatizableType = nullptr; | ||||
6306 | return ChangeStatus::CHANGED; | ||||
6307 | } | ||||
6308 | |||||
6309 | /// Identify the type we can chose for a private copy of the underlying | ||||
6310 | /// argument. None means it is not clear yet, nullptr means there is none. | ||||
6311 | virtual Optional<Type *> identifyPrivatizableType(Attributor &A) = 0; | ||||
6312 | |||||
6313 | /// Return a privatizable type that encloses both T0 and T1. | ||||
6314 | /// TODO: This is merely a stub for now as we should manage a mapping as well. | ||||
6315 | Optional<Type *> combineTypes(Optional<Type *> T0, Optional<Type *> T1) { | ||||
6316 | if (!T0.hasValue()) | ||||
6317 | return T1; | ||||
6318 | if (!T1.hasValue()) | ||||
6319 | return T0; | ||||
6320 | if (T0 == T1) | ||||
6321 | return T0; | ||||
6322 | return nullptr; | ||||
6323 | } | ||||
6324 | |||||
6325 | Optional<Type *> getPrivatizableType() const override { | ||||
6326 | return PrivatizableType; | ||||
6327 | } | ||||
6328 | |||||
6329 | const std::string getAsStr() const override { | ||||
6330 | return isAssumedPrivatizablePtr() ? "[priv]" : "[no-priv]"; | ||||
6331 | } | ||||
6332 | |||||
6333 | protected: | ||||
6334 | Optional<Type *> PrivatizableType; | ||||
6335 | }; | ||||
6336 | |||||
6337 | // TODO: Do this for call site arguments (probably also other values) as well. | ||||
6338 | |||||
6339 | struct AAPrivatizablePtrArgument final : public AAPrivatizablePtrImpl { | ||||
6340 | AAPrivatizablePtrArgument(const IRPosition &IRP, Attributor &A) | ||||
6341 | : AAPrivatizablePtrImpl(IRP, A) {} | ||||
6342 | |||||
6343 | /// See AAPrivatizablePtrImpl::identifyPrivatizableType(...) | ||||
6344 | Optional<Type *> identifyPrivatizableType(Attributor &A) override { | ||||
6345 | // If this is a byval argument and we know all the call sites (so we can | ||||
6346 | // rewrite them), there is no need to check them explicitly. | ||||
6347 | bool AllCallSitesKnown; | ||||
6348 | if (getIRPosition().hasAttr(Attribute::ByVal) && | ||||
6349 | A.checkForAllCallSites([](AbstractCallSite ACS) { return true; }, *this, | ||||
6350 | true, AllCallSitesKnown)) | ||||
6351 | return getAssociatedValue().getType()->getPointerElementType(); | ||||
6352 | |||||
6353 | Optional<Type *> Ty; | ||||
6354 | unsigned ArgNo = getIRPosition().getCallSiteArgNo(); | ||||
6355 | |||||
6356 | // Make sure the associated call site argument has the same type at all call | ||||
6357 | // sites and it is an allocation we know is safe to privatize, for now that | ||||
6358 | // means we only allow alloca instructions. | ||||
6359 | // TODO: We can additionally analyze the accesses in the callee to create | ||||
6360 | // the type from that information instead. That is a little more | ||||
6361 | // involved and will be done in a follow up patch. | ||||
6362 | auto CallSiteCheck = [&](AbstractCallSite ACS) { | ||||
6363 | IRPosition ACSArgPos = IRPosition::callsite_argument(ACS, ArgNo); | ||||
6364 | // Check if a coresponding argument was found or if it is one not | ||||
6365 | // associated (which can happen for callback calls). | ||||
6366 | if (ACSArgPos.getPositionKind() == IRPosition::IRP_INVALID) | ||||
6367 | return false; | ||||
6368 | |||||
6369 | // Check that all call sites agree on a type. | ||||
6370 | auto &PrivCSArgAA = | ||||
6371 | A.getAAFor<AAPrivatizablePtr>(*this, ACSArgPos, DepClassTy::REQUIRED); | ||||
6372 | Optional<Type *> CSTy = PrivCSArgAA.getPrivatizableType(); | ||||
6373 | |||||
6374 | LLVM_DEBUG({do { } while (false) | ||||
6375 | dbgs() << "[AAPrivatizablePtr] ACSPos: " << ACSArgPos << ", CSTy: ";do { } while (false) | ||||
6376 | if (CSTy.hasValue() && CSTy.getValue())do { } while (false) | ||||
6377 | CSTy.getValue()->print(dbgs());do { } while (false) | ||||
6378 | else if (CSTy.hasValue())do { } while (false) | ||||
6379 | dbgs() << "<nullptr>";do { } while (false) | ||||
6380 | elsedo { } while (false) | ||||
6381 | dbgs() << "<none>";do { } while (false) | ||||
6382 | })do { } while (false); | ||||
6383 | |||||
6384 | Ty = combineTypes(Ty, CSTy); | ||||
6385 | |||||
6386 | LLVM_DEBUG({do { } while (false) | ||||
6387 | dbgs() << " : New Type: ";do { } while (false) | ||||
6388 | if (Ty.hasValue() && Ty.getValue())do { } while (false) | ||||
6389 | Ty.getValue()->print(dbgs());do { } while (false) | ||||
6390 | else if (Ty.hasValue())do { } while (false) | ||||
6391 | dbgs() << "<nullptr>";do { } while (false) | ||||
6392 | elsedo { } while (false) | ||||
6393 | dbgs() << "<none>";do { } while (false) | ||||
6394 | dbgs() << "\n";do { } while (false) | ||||
6395 | })do { } while (false); | ||||
6396 | |||||
6397 | return !Ty.hasValue() || Ty.getValue(); | ||||
6398 | }; | ||||
6399 | |||||
6400 | if (!A.checkForAllCallSites(CallSiteCheck, *this, true, AllCallSitesKnown)) | ||||
6401 | return nullptr; | ||||
6402 | return Ty; | ||||
6403 | } | ||||
6404 | |||||
6405 | /// See AbstractAttribute::updateImpl(...). | ||||
6406 | ChangeStatus updateImpl(Attributor &A) override { | ||||
6407 | PrivatizableType = identifyPrivatizableType(A); | ||||
6408 | if (!PrivatizableType.hasValue()) | ||||
6409 | return ChangeStatus::UNCHANGED; | ||||
6410 | if (!PrivatizableType.getValue()) | ||||
6411 | return indicatePessimisticFixpoint(); | ||||
6412 | |||||
6413 | // The dependence is optional so we don't give up once we give up on the | ||||
6414 | // alignment. | ||||
6415 | A.getAAFor<AAAlign>(*this, IRPosition::value(getAssociatedValue()), | ||||
6416 | DepClassTy::OPTIONAL); | ||||
6417 | |||||
6418 | // Avoid arguments with padding for now. | ||||
6419 | if (!getIRPosition().hasAttr(Attribute::ByVal) && | ||||
6420 | !ArgumentPromotionPass::isDenselyPacked(PrivatizableType.getValue(), | ||||
6421 | A.getInfoCache().getDL())) { | ||||
6422 | LLVM_DEBUG(dbgs() << "[AAPrivatizablePtr] Padding detected\n")do { } while (false); | ||||
6423 | return indicatePessimisticFixpoint(); | ||||
6424 | } | ||||
6425 | |||||
6426 | // Verify callee and caller agree on how the promoted argument would be | ||||
6427 | // passed. | ||||
6428 | // TODO: The use of the ArgumentPromotion interface here is ugly, we need a | ||||
6429 | // specialized form of TargetTransformInfo::areFunctionArgsABICompatible | ||||
6430 | // which doesn't require the arguments ArgumentPromotion wanted to pass. | ||||
6431 | Function &Fn = *getIRPosition().getAnchorScope(); | ||||
6432 | SmallPtrSet<Argument *, 1> ArgsToPromote, Dummy; | ||||
6433 | ArgsToPromote.insert(getAssociatedArgument()); | ||||
6434 | const auto *TTI = | ||||
6435 | A.getInfoCache().getAnalysisResultForFunction<TargetIRAnalysis>(Fn); | ||||
6436 | if (!TTI || | ||||
6437 | !ArgumentPromotionPass::areFunctionArgsABICompatible( | ||||
6438 | Fn, *TTI, ArgsToPromote, Dummy) || | ||||
6439 | ArgsToPromote.empty()) { | ||||
6440 | LLVM_DEBUG(do { } while (false) | ||||
6441 | dbgs() << "[AAPrivatizablePtr] ABI incompatibility detected for "do { } while (false) | ||||
6442 | << Fn.getName() << "\n")do { } while (false); | ||||
6443 | return indicatePessimisticFixpoint(); | ||||
6444 | } | ||||
6445 | |||||
6446 | // Collect the types that will replace the privatizable type in the function | ||||
6447 | // signature. | ||||
6448 | SmallVector<Type *, 16> ReplacementTypes; | ||||
6449 | identifyReplacementTypes(PrivatizableType.getValue(), ReplacementTypes); | ||||
6450 | |||||
6451 | // Register a rewrite of the argument. | ||||
6452 | Argument *Arg = getAssociatedArgument(); | ||||
6453 | if (!A.isValidFunctionSignatureRewrite(*Arg, ReplacementTypes)) { | ||||
6454 | LLVM_DEBUG(dbgs() << "[AAPrivatizablePtr] Rewrite not valid\n")do { } while (false); | ||||
6455 | return indicatePessimisticFixpoint(); | ||||
6456 | } | ||||
6457 | |||||
6458 | unsigned ArgNo = Arg->getArgNo(); | ||||
6459 | |||||
6460 | // Helper to check if for the given call site the associated argument is | ||||
6461 | // passed to a callback where the privatization would be different. | ||||
6462 | auto IsCompatiblePrivArgOfCallback = [&](CallBase &CB) { | ||||
6463 | SmallVector<const Use *, 4> CallbackUses; | ||||
6464 | AbstractCallSite::getCallbackUses(CB, CallbackUses); | ||||
6465 | for (const Use *U : CallbackUses) { | ||||
6466 | AbstractCallSite CBACS(U); | ||||
6467 | assert(CBACS && CBACS.isCallbackCall())(static_cast<void> (0)); | ||||
6468 | for (Argument &CBArg : CBACS.getCalledFunction()->args()) { | ||||
6469 | int CBArgNo = CBACS.getCallArgOperandNo(CBArg); | ||||
6470 | |||||
6471 | LLVM_DEBUG({do { } while (false) | ||||
6472 | dbgs()do { } while (false) | ||||
6473 | << "[AAPrivatizablePtr] Argument " << *Argdo { } while (false) | ||||
6474 | << "check if can be privatized in the context of its parent ("do { } while (false) | ||||
6475 | << Arg->getParent()->getName()do { } while (false) | ||||
6476 | << ")\n[AAPrivatizablePtr] because it is an argument in a "do { } while (false) | ||||
6477 | "callback ("do { } while (false) | ||||
6478 | << CBArgNo << "@" << CBACS.getCalledFunction()->getName()do { } while (false) | ||||
6479 | << ")\n[AAPrivatizablePtr] " << CBArg << " : "do { } while (false) | ||||
6480 | << CBACS.getCallArgOperand(CBArg) << " vs "do { } while (false) | ||||
6481 | << CB.getArgOperand(ArgNo) << "\n"do { } while (false) | ||||
6482 | << "[AAPrivatizablePtr] " << CBArg << " : "do { } while (false) | ||||
6483 | << CBACS.getCallArgOperandNo(CBArg) << " vs " << ArgNo << "\n";do { } while (false) | ||||
6484 | })do { } while (false); | ||||
6485 | |||||
6486 | if (CBArgNo != int(ArgNo)) | ||||
6487 | continue; | ||||
6488 | const auto &CBArgPrivAA = A.getAAFor<AAPrivatizablePtr>( | ||||
6489 | *this, IRPosition::argument(CBArg), DepClassTy::REQUIRED); | ||||
6490 | if (CBArgPrivAA.isValidState()) { | ||||
6491 | auto CBArgPrivTy = CBArgPrivAA.getPrivatizableType(); | ||||
6492 | if (!CBArgPrivTy.hasValue()) | ||||
6493 | continue; | ||||
6494 | if (CBArgPrivTy.getValue() == PrivatizableType) | ||||
6495 | continue; | ||||
6496 | } | ||||
6497 | |||||
6498 | LLVM_DEBUG({do { } while (false) | ||||
6499 | dbgs() << "[AAPrivatizablePtr] Argument " << *Argdo { } while (false) | ||||
6500 | << " cannot be privatized in the context of its parent ("do { } while (false) | ||||
6501 | << Arg->getParent()->getName()do { } while (false) | ||||
6502 | << ")\n[AAPrivatizablePtr] because it is an argument in a "do { } while (false) | ||||
6503 | "callback ("do { } while (false) | ||||
6504 | << CBArgNo << "@" << CBACS.getCalledFunction()->getName()do { } while (false) | ||||
6505 | << ").\n[AAPrivatizablePtr] for which the argument "do { } while (false) | ||||
6506 | "privatization is not compatible.\n";do { } while (false) | ||||
6507 | })do { } while (false); | ||||
6508 | return false; | ||||
6509 | } | ||||
6510 | } | ||||
6511 | return true; | ||||
6512 | }; | ||||
6513 | |||||
6514 | // Helper to check if for the given call site the associated argument is | ||||
6515 | // passed to a direct call where the privatization would be different. | ||||
6516 | auto IsCompatiblePrivArgOfDirectCS = [&](AbstractCallSite ACS) { | ||||
6517 | CallBase *DC = cast<CallBase>(ACS.getInstruction()); | ||||
6518 | int DCArgNo = ACS.getCallArgOperandNo(ArgNo); | ||||
6519 | assert(DCArgNo >= 0 && unsigned(DCArgNo) < DC->getNumArgOperands() &&(static_cast<void> (0)) | ||||
6520 | "Expected a direct call operand for callback call operand")(static_cast<void> (0)); | ||||
6521 | |||||
6522 | LLVM_DEBUG({do { } while (false) | ||||
6523 | dbgs() << "[AAPrivatizablePtr] Argument " << *Argdo { } while (false) | ||||
6524 | << " check if be privatized in the context of its parent ("do { } while (false) | ||||
6525 | << Arg->getParent()->getName()do { } while (false) | ||||
6526 | << ")\n[AAPrivatizablePtr] because it is an argument in a "do { } while (false) | ||||
6527 | "direct call of ("do { } while (false) | ||||
6528 | << DCArgNo << "@" << DC->getCalledFunction()->getName()do { } while (false) | ||||
6529 | << ").\n";do { } while (false) | ||||
6530 | })do { } while (false); | ||||
6531 | |||||
6532 | Function *DCCallee = DC->getCalledFunction(); | ||||
6533 | if (unsigned(DCArgNo) < DCCallee->arg_size()) { | ||||
6534 | const auto &DCArgPrivAA = A.getAAFor<AAPrivatizablePtr>( | ||||
6535 | *this, IRPosition::argument(*DCCallee->getArg(DCArgNo)), | ||||
6536 | DepClassTy::REQUIRED); | ||||
6537 | if (DCArgPrivAA.isValidState()) { | ||||
6538 | auto DCArgPrivTy = DCArgPrivAA.getPrivatizableType(); | ||||
6539 | if (!DCArgPrivTy.hasValue()) | ||||
6540 | return true; | ||||
6541 | if (DCArgPrivTy.getValue() == PrivatizableType) | ||||
6542 | return true; | ||||
6543 | } | ||||
6544 | } | ||||
6545 | |||||
6546 | LLVM_DEBUG({do { } while (false) | ||||
6547 | dbgs() << "[AAPrivatizablePtr] Argument " << *Argdo { } while (false) | ||||
6548 | << " cannot be privatized in the context of its parent ("do { } while (false) | ||||
6549 | << Arg->getParent()->getName()do { } while (false) | ||||
6550 | << ")\n[AAPrivatizablePtr] because it is an argument in a "do { } while (false) | ||||
6551 | "direct call of ("do { } while (false) | ||||
6552 | << ACS.getInstruction()->getCalledFunction()->getName()do { } while (false) | ||||
6553 | << ").\n[AAPrivatizablePtr] for which the argument "do { } while (false) | ||||
6554 | "privatization is not compatible.\n";do { } while (false) | ||||
6555 | })do { } while (false); | ||||
6556 | return false; | ||||
6557 | }; | ||||
6558 | |||||
6559 | // Helper to check if the associated argument is used at the given abstract | ||||
6560 | // call site in a way that is incompatible with the privatization assumed | ||||
6561 | // here. | ||||
6562 | auto IsCompatiblePrivArgOfOtherCallSite = [&](AbstractCallSite ACS) { | ||||
6563 | if (ACS.isDirectCall()) | ||||
6564 | return IsCompatiblePrivArgOfCallback(*ACS.getInstruction()); | ||||
6565 | if (ACS.isCallbackCall()) | ||||
6566 | return IsCompatiblePrivArgOfDirectCS(ACS); | ||||
6567 | return false; | ||||
6568 | }; | ||||
6569 | |||||
6570 | bool AllCallSitesKnown; | ||||
6571 | if (!A.checkForAllCallSites(IsCompatiblePrivArgOfOtherCallSite, *this, true, | ||||
6572 | AllCallSitesKnown)) | ||||
6573 | return indicatePessimisticFixpoint(); | ||||
6574 | |||||
6575 | return ChangeStatus::UNCHANGED; | ||||
6576 | } | ||||
6577 | |||||
6578 | /// Given a type to private \p PrivType, collect the constituates (which are | ||||
6579 | /// used) in \p ReplacementTypes. | ||||
6580 | static void | ||||
6581 | identifyReplacementTypes(Type *PrivType, | ||||
6582 | SmallVectorImpl<Type *> &ReplacementTypes) { | ||||
6583 | // TODO: For now we expand the privatization type to the fullest which can | ||||
6584 | // lead to dead arguments that need to be removed later. | ||||
6585 | assert(PrivType && "Expected privatizable type!")(static_cast<void> (0)); | ||||
6586 | |||||
6587 | // Traverse the type, extract constituate types on the outermost level. | ||||
6588 | if (auto *PrivStructType = dyn_cast<StructType>(PrivType)) { | ||||
6589 | for (unsigned u = 0, e = PrivStructType->getNumElements(); u < e; u++) | ||||
6590 | ReplacementTypes.push_back(PrivStructType->getElementType(u)); | ||||
6591 | } else if (auto *PrivArrayType = dyn_cast<ArrayType>(PrivType)) { | ||||
6592 | ReplacementTypes.append(PrivArrayType->getNumElements(), | ||||
6593 | PrivArrayType->getElementType()); | ||||
6594 | } else { | ||||
6595 | ReplacementTypes.push_back(PrivType); | ||||
6596 | } | ||||
6597 | } | ||||
6598 | |||||
6599 | /// Initialize \p Base according to the type \p PrivType at position \p IP. | ||||
6600 | /// The values needed are taken from the arguments of \p F starting at | ||||
6601 | /// position \p ArgNo. | ||||
6602 | static void createInitialization(Type *PrivType, Value &Base, Function &F, | ||||
6603 | unsigned ArgNo, Instruction &IP) { | ||||
6604 | assert(PrivType && "Expected privatizable type!")(static_cast<void> (0)); | ||||
6605 | |||||
6606 | IRBuilder<NoFolder> IRB(&IP); | ||||
6607 | const DataLayout &DL = F.getParent()->getDataLayout(); | ||||
6608 | |||||
6609 | // Traverse the type, build GEPs and stores. | ||||
6610 | if (auto *PrivStructType = dyn_cast<StructType>(PrivType)) { | ||||
6611 | const StructLayout *PrivStructLayout = DL.getStructLayout(PrivStructType); | ||||
6612 | for (unsigned u = 0, e = PrivStructType->getNumElements(); u < e; u++) { | ||||
6613 | Type *PointeeTy = PrivStructType->getElementType(u)->getPointerTo(); | ||||
6614 | Value *Ptr = | ||||
6615 | constructPointer(PointeeTy, PrivType, &Base, | ||||
6616 | PrivStructLayout->getElementOffset(u), IRB, DL); | ||||
6617 | new StoreInst(F.getArg(ArgNo + u), Ptr, &IP); | ||||
6618 | } | ||||
6619 | } else if (auto *PrivArrayType = dyn_cast<ArrayType>(PrivType)) { | ||||
6620 | Type *PointeeTy = PrivArrayType->getElementType(); | ||||
6621 | Type *PointeePtrTy = PointeeTy->getPointerTo(); | ||||
6622 | uint64_t PointeeTySize = DL.getTypeStoreSize(PointeeTy); | ||||
6623 | for (unsigned u = 0, e = PrivArrayType->getNumElements(); u < e; u++) { | ||||
6624 | Value *Ptr = constructPointer(PointeePtrTy, PrivType, &Base, | ||||
6625 | u * PointeeTySize, IRB, DL); | ||||
6626 | new StoreInst(F.getArg(ArgNo + u), Ptr, &IP); | ||||
6627 | } | ||||
6628 | } else { | ||||
6629 | new StoreInst(F.getArg(ArgNo), &Base, &IP); | ||||
6630 | } | ||||
6631 | } | ||||
6632 | |||||
6633 | /// Extract values from \p Base according to the type \p PrivType at the | ||||
6634 | /// call position \p ACS. The values are appended to \p ReplacementValues. | ||||
6635 | void createReplacementValues(Align Alignment, Type *PrivType, | ||||
6636 | AbstractCallSite ACS, Value *Base, | ||||
6637 | SmallVectorImpl<Value *> &ReplacementValues) { | ||||
6638 | assert(Base && "Expected base value!")(static_cast<void> (0)); | ||||
6639 | assert(PrivType && "Expected privatizable type!")(static_cast<void> (0)); | ||||
6640 | Instruction *IP = ACS.getInstruction(); | ||||
6641 | |||||
6642 | IRBuilder<NoFolder> IRB(IP); | ||||
6643 | const DataLayout &DL = IP->getModule()->getDataLayout(); | ||||
6644 | |||||
6645 | if (Base->getType()->getPointerElementType() != PrivType) | ||||
6646 | Base = BitCastInst::CreateBitOrPointerCast(Base, PrivType->getPointerTo(), | ||||
6647 | "", ACS.getInstruction()); | ||||
6648 | |||||
6649 | // Traverse the type, build GEPs and loads. | ||||
6650 | if (auto *PrivStructType = dyn_cast<StructType>(PrivType)) { | ||||
6651 | const StructLayout *PrivStructLayout = DL.getStructLayout(PrivStructType); | ||||
6652 | for (unsigned u = 0, e = PrivStructType->getNumElements(); u < e; u++) { | ||||
6653 | Type *PointeeTy = PrivStructType->getElementType(u); | ||||
6654 | Value *Ptr = | ||||
6655 | constructPointer(PointeeTy->getPointerTo(), PrivType, Base, | ||||
6656 | PrivStructLayout->getElementOffset(u), IRB, DL); | ||||
6657 | LoadInst *L = new LoadInst(PointeeTy, Ptr, "", IP); | ||||
6658 | L->setAlignment(Alignment); | ||||
6659 | ReplacementValues.push_back(L); | ||||
6660 | } | ||||
6661 | } else if (auto *PrivArrayType = dyn_cast<ArrayType>(PrivType)) { | ||||
6662 | Type *PointeeTy = PrivArrayType->getElementType(); | ||||
6663 | uint64_t PointeeTySize = DL.getTypeStoreSize(PointeeTy); | ||||
6664 | Type *PointeePtrTy = PointeeTy->getPointerTo(); | ||||
6665 | for (unsigned u = 0, e = PrivArrayType->getNumElements(); u < e; u++) { | ||||
6666 | Value *Ptr = constructPointer(PointeePtrTy, PrivType, Base, | ||||
6667 | u * PointeeTySize, IRB, DL); | ||||
6668 | LoadInst *L = new LoadInst(PointeeTy, Ptr, "", IP); | ||||
6669 | L->setAlignment(Alignment); | ||||
6670 | ReplacementValues.push_back(L); | ||||
6671 | } | ||||
6672 | } else { | ||||
6673 | LoadInst *L = new LoadInst(PrivType, Base, "", IP); | ||||
6674 | L->setAlignment(Alignment); | ||||
6675 | ReplacementValues.push_back(L); | ||||
6676 | } | ||||
6677 | } | ||||
6678 | |||||
6679 | /// See AbstractAttribute::manifest(...) | ||||
6680 | ChangeStatus manifest(Attributor &A) override { | ||||
6681 | if (!PrivatizableType.hasValue()) | ||||
6682 | return ChangeStatus::UNCHANGED; | ||||
6683 | assert(PrivatizableType.getValue() && "Expected privatizable type!")(static_cast<void> (0)); | ||||
6684 | |||||
6685 | // Collect all tail calls in the function as we cannot allow new allocas to | ||||
6686 | // escape into tail recursion. | ||||
6687 | // TODO: Be smarter about new allocas escaping into tail calls. | ||||
6688 | SmallVector<CallInst *, 16> TailCalls; | ||||
6689 | bool UsedAssumedInformation = false; | ||||
6690 | if (!A.checkForAllInstructions( | ||||
6691 | [&](Instruction &I) { | ||||
6692 | CallInst &CI = cast<CallInst>(I); | ||||
6693 | if (CI.isTailCall()) | ||||
6694 | TailCalls.push_back(&CI); | ||||
6695 | return true; | ||||
6696 | }, | ||||
6697 | *this, {Instruction::Call}, UsedAssumedInformation)) | ||||
6698 | return ChangeStatus::UNCHANGED; | ||||
6699 | |||||
6700 | Argument *Arg = getAssociatedArgument(); | ||||
6701 | // Query AAAlign attribute for alignment of associated argument to | ||||
6702 | // determine the best alignment of loads. | ||||
6703 | const auto &AlignAA = | ||||
6704 | A.getAAFor<AAAlign>(*this, IRPosition::value(*Arg), DepClassTy::NONE); | ||||
6705 | |||||
6706 | // Callback to repair the associated function. A new alloca is placed at the | ||||
6707 | // beginning and initialized with the values passed through arguments. The | ||||
6708 | // new alloca replaces the use of the old pointer argument. | ||||
6709 | Attributor::ArgumentReplacementInfo::CalleeRepairCBTy FnRepairCB = | ||||
6710 | [=](const Attributor::ArgumentReplacementInfo &ARI, | ||||
6711 | Function &ReplacementFn, Function::arg_iterator ArgIt) { | ||||
6712 | BasicBlock &EntryBB = ReplacementFn.getEntryBlock(); | ||||
6713 | Instruction *IP = &*EntryBB.getFirstInsertionPt(); | ||||
6714 | Instruction *AI = new AllocaInst(PrivatizableType.getValue(), 0, | ||||
6715 | Arg->getName() + ".priv", IP); | ||||
6716 | createInitialization(PrivatizableType.getValue(), *AI, ReplacementFn, | ||||
6717 | ArgIt->getArgNo(), *IP); | ||||
6718 | |||||
6719 | if (AI->getType() != Arg->getType()) | ||||
6720 | AI = | ||||
6721 | BitCastInst::CreateBitOrPointerCast(AI, Arg->getType(), "", IP); | ||||
6722 | Arg->replaceAllUsesWith(AI); | ||||
6723 | |||||
6724 | for (CallInst *CI : TailCalls) | ||||
6725 | CI->setTailCall(false); | ||||
6726 | }; | ||||
6727 | |||||
6728 | // Callback to repair a call site of the associated function. The elements | ||||
6729 | // of the privatizable type are loaded prior to the call and passed to the | ||||
6730 | // new function version. | ||||
6731 | Attributor::ArgumentReplacementInfo::ACSRepairCBTy ACSRepairCB = | ||||
6732 | [=, &AlignAA](const Attributor::ArgumentReplacementInfo &ARI, | ||||
6733 | AbstractCallSite ACS, | ||||
6734 | SmallVectorImpl<Value *> &NewArgOperands) { | ||||
6735 | // When no alignment is specified for the load instruction, | ||||
6736 | // natural alignment is assumed. | ||||
6737 | createReplacementValues( | ||||
6738 | assumeAligned(AlignAA.getAssumedAlign()), | ||||
6739 | PrivatizableType.getValue(), ACS, | ||||
6740 | ACS.getCallArgOperand(ARI.getReplacedArg().getArgNo()), | ||||
6741 | NewArgOperands); | ||||
6742 | }; | ||||
6743 | |||||
6744 | // Collect the types that will replace the privatizable type in the function | ||||
6745 | // signature. | ||||
6746 | SmallVector<Type *, 16> ReplacementTypes; | ||||
6747 | identifyReplacementTypes(PrivatizableType.getValue(), ReplacementTypes); | ||||
6748 | |||||
6749 | // Register a rewrite of the argument. | ||||
6750 | if (A.registerFunctionSignatureRewrite(*Arg, ReplacementTypes, | ||||
6751 | std::move(FnRepairCB), | ||||
6752 | std::move(ACSRepairCB))) | ||||
6753 | return ChangeStatus::CHANGED; | ||||
6754 | return ChangeStatus::UNCHANGED; | ||||
6755 | } | ||||
6756 | |||||
6757 | /// See AbstractAttribute::trackStatistics() | ||||
6758 | void trackStatistics() const override { | ||||
6759 | STATS_DECLTRACK_ARG_ATTR(privatizable_ptr){ static llvm::Statistic NumIRArguments_privatizable_ptr = {"attributor" , "NumIRArguments_privatizable_ptr", ("Number of " "arguments" " marked '" "privatizable_ptr" "'")};; ++(NumIRArguments_privatizable_ptr ); }; | ||||
6760 | } | ||||
6761 | }; | ||||
6762 | |||||
6763 | struct AAPrivatizablePtrFloating : public AAPrivatizablePtrImpl { | ||||
6764 | AAPrivatizablePtrFloating(const IRPosition &IRP, Attributor &A) | ||||
6765 | : AAPrivatizablePtrImpl(IRP, A) {} | ||||
6766 | |||||
6767 | /// See AbstractAttribute::initialize(...). | ||||
6768 | virtual void initialize(Attributor &A) override { | ||||
6769 | // TODO: We can privatize more than arguments. | ||||
6770 | indicatePessimisticFixpoint(); | ||||
6771 | } | ||||
6772 | |||||
6773 | ChangeStatus updateImpl(Attributor &A) override { | ||||
6774 | llvm_unreachable("AAPrivatizablePtr(Floating|Returned|CallSiteReturned)::"__builtin_unreachable() | ||||
6775 | "updateImpl will not be called")__builtin_unreachable(); | ||||
6776 | } | ||||
6777 | |||||
6778 | /// See AAPrivatizablePtrImpl::identifyPrivatizableType(...) | ||||
6779 | Optional<Type *> identifyPrivatizableType(Attributor &A) override { | ||||
6780 | Value *Obj = getUnderlyingObject(&getAssociatedValue()); | ||||
6781 | if (!Obj) { | ||||
6782 | LLVM_DEBUG(dbgs() << "[AAPrivatizablePtr] No underlying object found!\n")do { } while (false); | ||||
6783 | return nullptr; | ||||
6784 | } | ||||
6785 | |||||
6786 | if (auto *AI = dyn_cast<AllocaInst>(Obj)) | ||||
6787 | if (auto *CI = dyn_cast<ConstantInt>(AI->getArraySize())) | ||||
6788 | if (CI->isOne()) | ||||
6789 | return Obj->getType()->getPointerElementType(); | ||||
6790 | if (auto *Arg = dyn_cast<Argument>(Obj)) { | ||||
6791 | auto &PrivArgAA = A.getAAFor<AAPrivatizablePtr>( | ||||
6792 | *this, IRPosition::argument(*Arg), DepClassTy::REQUIRED); | ||||
6793 | if (PrivArgAA.isAssumedPrivatizablePtr()) | ||||
6794 | return Obj->getType()->getPointerElementType(); | ||||
6795 | } | ||||
6796 | |||||
6797 | LLVM_DEBUG(dbgs() << "[AAPrivatizablePtr] Underlying object neither valid "do { } while (false) | ||||
6798 | "alloca nor privatizable argument: "do { } while (false) | ||||
6799 | << *Obj << "!\n")do { } while (false); | ||||
6800 | return nullptr; | ||||
6801 | } | ||||
6802 | |||||
6803 | /// See AbstractAttribute::trackStatistics() | ||||
6804 | void trackStatistics() const override { | ||||
6805 | STATS_DECLTRACK_FLOATING_ATTR(privatizable_ptr){ static llvm::Statistic NumIRFloating_privatizable_ptr = {"attributor" , "NumIRFloating_privatizable_ptr", ("Number of floating values known to be '" "privatizable_ptr" "'")};; ++(NumIRFloating_privatizable_ptr ); }; | ||||
6806 | } | ||||
6807 | }; | ||||
6808 | |||||
6809 | struct AAPrivatizablePtrCallSiteArgument final | ||||
6810 | : public AAPrivatizablePtrFloating { | ||||
6811 | AAPrivatizablePtrCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
6812 | : AAPrivatizablePtrFloating(IRP, A) {} | ||||
6813 | |||||
6814 | /// See AbstractAttribute::initialize(...). | ||||
6815 | void initialize(Attributor &A) override { | ||||
6816 | if (getIRPosition().hasAttr(Attribute::ByVal)) | ||||
6817 | indicateOptimisticFixpoint(); | ||||
6818 | } | ||||
6819 | |||||
6820 | /// See AbstractAttribute::updateImpl(...). | ||||
6821 | ChangeStatus updateImpl(Attributor &A) override { | ||||
6822 | PrivatizableType = identifyPrivatizableType(A); | ||||
6823 | if (!PrivatizableType.hasValue()) | ||||
6824 | return ChangeStatus::UNCHANGED; | ||||
6825 | if (!PrivatizableType.getValue()) | ||||
6826 | return indicatePessimisticFixpoint(); | ||||
6827 | |||||
6828 | const IRPosition &IRP = getIRPosition(); | ||||
6829 | auto &NoCaptureAA = | ||||
6830 | A.getAAFor<AANoCapture>(*this, IRP, DepClassTy::REQUIRED); | ||||
6831 | if (!NoCaptureAA.isAssumedNoCapture()) { | ||||
6832 | LLVM_DEBUG(dbgs() << "[AAPrivatizablePtr] pointer might be captured!\n")do { } while (false); | ||||
6833 | return indicatePessimisticFixpoint(); | ||||
6834 | } | ||||
6835 | |||||
6836 | auto &NoAliasAA = A.getAAFor<AANoAlias>(*this, IRP, DepClassTy::REQUIRED); | ||||
6837 | if (!NoAliasAA.isAssumedNoAlias()) { | ||||
6838 | LLVM_DEBUG(dbgs() << "[AAPrivatizablePtr] pointer might alias!\n")do { } while (false); | ||||
6839 | return indicatePessimisticFixpoint(); | ||||
6840 | } | ||||
6841 | |||||
6842 | const auto &MemBehaviorAA = | ||||
6843 | A.getAAFor<AAMemoryBehavior>(*this, IRP, DepClassTy::REQUIRED); | ||||
6844 | if (!MemBehaviorAA.isAssumedReadOnly()) { | ||||
6845 | LLVM_DEBUG(dbgs() << "[AAPrivatizablePtr] pointer is written!\n")do { } while (false); | ||||
6846 | return indicatePessimisticFixpoint(); | ||||
6847 | } | ||||
6848 | |||||
6849 | return ChangeStatus::UNCHANGED; | ||||
6850 | } | ||||
6851 | |||||
6852 | /// See AbstractAttribute::trackStatistics() | ||||
6853 | void trackStatistics() const override { | ||||
6854 | STATS_DECLTRACK_CSARG_ATTR(privatizable_ptr){ static llvm::Statistic NumIRCSArguments_privatizable_ptr = { "attributor", "NumIRCSArguments_privatizable_ptr", ("Number of " "call site arguments" " marked '" "privatizable_ptr" "'")};; ++(NumIRCSArguments_privatizable_ptr); }; | ||||
6855 | } | ||||
6856 | }; | ||||
6857 | |||||
6858 | struct AAPrivatizablePtrCallSiteReturned final | ||||
6859 | : public AAPrivatizablePtrFloating { | ||||
6860 | AAPrivatizablePtrCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
6861 | : AAPrivatizablePtrFloating(IRP, A) {} | ||||
6862 | |||||
6863 | /// See AbstractAttribute::initialize(...). | ||||
6864 | void initialize(Attributor &A) override { | ||||
6865 | // TODO: We can privatize more than arguments. | ||||
6866 | indicatePessimisticFixpoint(); | ||||
6867 | } | ||||
6868 | |||||
6869 | /// See AbstractAttribute::trackStatistics() | ||||
6870 | void trackStatistics() const override { | ||||
6871 | STATS_DECLTRACK_CSRET_ATTR(privatizable_ptr){ static llvm::Statistic NumIRCSReturn_privatizable_ptr = {"attributor" , "NumIRCSReturn_privatizable_ptr", ("Number of " "call site returns" " marked '" "privatizable_ptr" "'")};; ++(NumIRCSReturn_privatizable_ptr ); }; | ||||
6872 | } | ||||
6873 | }; | ||||
6874 | |||||
6875 | struct AAPrivatizablePtrReturned final : public AAPrivatizablePtrFloating { | ||||
6876 | AAPrivatizablePtrReturned(const IRPosition &IRP, Attributor &A) | ||||
6877 | : AAPrivatizablePtrFloating(IRP, A) {} | ||||
6878 | |||||
6879 | /// See AbstractAttribute::initialize(...). | ||||
6880 | void initialize(Attributor &A) override { | ||||
6881 | // TODO: We can privatize more than arguments. | ||||
6882 | indicatePessimisticFixpoint(); | ||||
6883 | } | ||||
6884 | |||||
6885 | /// See AbstractAttribute::trackStatistics() | ||||
6886 | void trackStatistics() const override { | ||||
6887 | STATS_DECLTRACK_FNRET_ATTR(privatizable_ptr){ static llvm::Statistic NumIRFunctionReturn_privatizable_ptr = {"attributor", "NumIRFunctionReturn_privatizable_ptr", ("Number of " "function returns" " marked '" "privatizable_ptr" "'")};; ++ (NumIRFunctionReturn_privatizable_ptr); }; | ||||
6888 | } | ||||
6889 | }; | ||||
6890 | |||||
6891 | /// -------------------- Memory Behavior Attributes ---------------------------- | ||||
6892 | /// Includes read-none, read-only, and write-only. | ||||
6893 | /// ---------------------------------------------------------------------------- | ||||
6894 | struct AAMemoryBehaviorImpl : public AAMemoryBehavior { | ||||
6895 | AAMemoryBehaviorImpl(const IRPosition &IRP, Attributor &A) | ||||
6896 | : AAMemoryBehavior(IRP, A) {} | ||||
6897 | |||||
6898 | /// See AbstractAttribute::initialize(...). | ||||
6899 | void initialize(Attributor &A) override { | ||||
6900 | intersectAssumedBits(BEST_STATE); | ||||
6901 | getKnownStateFromValue(getIRPosition(), getState()); | ||||
6902 | AAMemoryBehavior::initialize(A); | ||||
6903 | } | ||||
6904 | |||||
6905 | /// Return the memory behavior information encoded in the IR for \p IRP. | ||||
6906 | static void getKnownStateFromValue(const IRPosition &IRP, | ||||
6907 | BitIntegerState &State, | ||||
6908 | bool IgnoreSubsumingPositions = false) { | ||||
6909 | SmallVector<Attribute, 2> Attrs; | ||||
6910 | IRP.getAttrs(AttrKinds, Attrs, IgnoreSubsumingPositions); | ||||
6911 | for (const Attribute &Attr : Attrs) { | ||||
6912 | switch (Attr.getKindAsEnum()) { | ||||
6913 | case Attribute::ReadNone: | ||||
6914 | State.addKnownBits(NO_ACCESSES); | ||||
6915 | break; | ||||
6916 | case Attribute::ReadOnly: | ||||
6917 | State.addKnownBits(NO_WRITES); | ||||
6918 | break; | ||||
6919 | case Attribute::WriteOnly: | ||||
6920 | State.addKnownBits(NO_READS); | ||||
6921 | break; | ||||
6922 | default: | ||||
6923 | llvm_unreachable("Unexpected attribute!")__builtin_unreachable(); | ||||
6924 | } | ||||
6925 | } | ||||
6926 | |||||
6927 | if (auto *I = dyn_cast<Instruction>(&IRP.getAnchorValue())) { | ||||
6928 | if (!I->mayReadFromMemory()) | ||||
6929 | State.addKnownBits(NO_READS); | ||||
6930 | if (!I->mayWriteToMemory()) | ||||
6931 | State.addKnownBits(NO_WRITES); | ||||
6932 | } | ||||
6933 | } | ||||
6934 | |||||
6935 | /// See AbstractAttribute::getDeducedAttributes(...). | ||||
6936 | void getDeducedAttributes(LLVMContext &Ctx, | ||||
6937 | SmallVectorImpl<Attribute> &Attrs) const override { | ||||
6938 | assert(Attrs.size() == 0)(static_cast<void> (0)); | ||||
6939 | if (isAssumedReadNone()) | ||||
6940 | Attrs.push_back(Attribute::get(Ctx, Attribute::ReadNone)); | ||||
6941 | else if (isAssumedReadOnly()) | ||||
6942 | Attrs.push_back(Attribute::get(Ctx, Attribute::ReadOnly)); | ||||
6943 | else if (isAssumedWriteOnly()) | ||||
6944 | Attrs.push_back(Attribute::get(Ctx, Attribute::WriteOnly)); | ||||
6945 | assert(Attrs.size() <= 1)(static_cast<void> (0)); | ||||
6946 | } | ||||
6947 | |||||
6948 | /// See AbstractAttribute::manifest(...). | ||||
6949 | ChangeStatus manifest(Attributor &A) override { | ||||
6950 | if (hasAttr(Attribute::ReadNone, /* IgnoreSubsumingPositions */ true)) | ||||
6951 | return ChangeStatus::UNCHANGED; | ||||
6952 | |||||
6953 | const IRPosition &IRP = getIRPosition(); | ||||
6954 | |||||
6955 | // Check if we would improve the existing attributes first. | ||||
6956 | SmallVector<Attribute, 4> DeducedAttrs; | ||||
6957 | getDeducedAttributes(IRP.getAnchorValue().getContext(), DeducedAttrs); | ||||
6958 | if (llvm::all_of(DeducedAttrs, [&](const Attribute &Attr) { | ||||
6959 | return IRP.hasAttr(Attr.getKindAsEnum(), | ||||
6960 | /* IgnoreSubsumingPositions */ true); | ||||
6961 | })) | ||||
6962 | return ChangeStatus::UNCHANGED; | ||||
6963 | |||||
6964 | // Clear existing attributes. | ||||
6965 | IRP.removeAttrs(AttrKinds); | ||||
6966 | |||||
6967 | // Use the generic manifest method. | ||||
6968 | return IRAttribute::manifest(A); | ||||
6969 | } | ||||
6970 | |||||
6971 | /// See AbstractState::getAsStr(). | ||||
6972 | const std::string getAsStr() const override { | ||||
6973 | if (isAssumedReadNone()) | ||||
6974 | return "readnone"; | ||||
6975 | if (isAssumedReadOnly()) | ||||
6976 | return "readonly"; | ||||
6977 | if (isAssumedWriteOnly()) | ||||
6978 | return "writeonly"; | ||||
6979 | return "may-read/write"; | ||||
6980 | } | ||||
6981 | |||||
6982 | /// The set of IR attributes AAMemoryBehavior deals with. | ||||
6983 | static const Attribute::AttrKind AttrKinds[3]; | ||||
6984 | }; | ||||
6985 | |||||
6986 | const Attribute::AttrKind AAMemoryBehaviorImpl::AttrKinds[] = { | ||||
6987 | Attribute::ReadNone, Attribute::ReadOnly, Attribute::WriteOnly}; | ||||
6988 | |||||
6989 | /// Memory behavior attribute for a floating value. | ||||
6990 | struct AAMemoryBehaviorFloating : AAMemoryBehaviorImpl { | ||||
6991 | AAMemoryBehaviorFloating(const IRPosition &IRP, Attributor &A) | ||||
6992 | : AAMemoryBehaviorImpl(IRP, A) {} | ||||
6993 | |||||
6994 | /// See AbstractAttribute::updateImpl(...). | ||||
6995 | ChangeStatus updateImpl(Attributor &A) override; | ||||
6996 | |||||
6997 | /// See AbstractAttribute::trackStatistics() | ||||
6998 | void trackStatistics() const override { | ||||
6999 | if (isAssumedReadNone()) | ||||
7000 | STATS_DECLTRACK_FLOATING_ATTR(readnone){ static llvm::Statistic NumIRFloating_readnone = {"attributor" , "NumIRFloating_readnone", ("Number of floating values known to be '" "readnone" "'")};; ++(NumIRFloating_readnone); } | ||||
7001 | else if (isAssumedReadOnly()) | ||||
7002 | STATS_DECLTRACK_FLOATING_ATTR(readonly){ static llvm::Statistic NumIRFloating_readonly = {"attributor" , "NumIRFloating_readonly", ("Number of floating values known to be '" "readonly" "'")};; ++(NumIRFloating_readonly); } | ||||
7003 | else if (isAssumedWriteOnly()) | ||||
7004 | STATS_DECLTRACK_FLOATING_ATTR(writeonly){ static llvm::Statistic NumIRFloating_writeonly = {"attributor" , "NumIRFloating_writeonly", ("Number of floating values known to be '" "writeonly" "'")};; ++(NumIRFloating_writeonly); } | ||||
7005 | } | ||||
7006 | |||||
7007 | private: | ||||
7008 | /// Return true if users of \p UserI might access the underlying | ||||
7009 | /// variable/location described by \p U and should therefore be analyzed. | ||||
7010 | bool followUsersOfUseIn(Attributor &A, const Use &U, | ||||
7011 | const Instruction *UserI); | ||||
7012 | |||||
7013 | /// Update the state according to the effect of use \p U in \p UserI. | ||||
7014 | void analyzeUseIn(Attributor &A, const Use &U, const Instruction *UserI); | ||||
7015 | }; | ||||
7016 | |||||
7017 | /// Memory behavior attribute for function argument. | ||||
7018 | struct AAMemoryBehaviorArgument : AAMemoryBehaviorFloating { | ||||
7019 | AAMemoryBehaviorArgument(const IRPosition &IRP, Attributor &A) | ||||
7020 | : AAMemoryBehaviorFloating(IRP, A) {} | ||||
7021 | |||||
7022 | /// See AbstractAttribute::initialize(...). | ||||
7023 | void initialize(Attributor &A) override { | ||||
7024 | intersectAssumedBits(BEST_STATE); | ||||
7025 | const IRPosition &IRP = getIRPosition(); | ||||
7026 | // TODO: Make IgnoreSubsumingPositions a property of an IRAttribute so we | ||||
7027 | // can query it when we use has/getAttr. That would allow us to reuse the | ||||
7028 | // initialize of the base class here. | ||||
7029 | bool HasByVal = | ||||
7030 | IRP.hasAttr({Attribute::ByVal}, /* IgnoreSubsumingPositions */ true); | ||||
7031 | getKnownStateFromValue(IRP, getState(), | ||||
7032 | /* IgnoreSubsumingPositions */ HasByVal); | ||||
7033 | |||||
7034 | // Initialize the use vector with all direct uses of the associated value. | ||||
7035 | Argument *Arg = getAssociatedArgument(); | ||||
7036 | if (!Arg || !A.isFunctionIPOAmendable(*(Arg->getParent()))) | ||||
7037 | indicatePessimisticFixpoint(); | ||||
7038 | } | ||||
7039 | |||||
7040 | ChangeStatus manifest(Attributor &A) override { | ||||
7041 | // TODO: Pointer arguments are not supported on vectors of pointers yet. | ||||
7042 | if (!getAssociatedValue().getType()->isPointerTy()) | ||||
7043 | return ChangeStatus::UNCHANGED; | ||||
7044 | |||||
7045 | // TODO: From readattrs.ll: "inalloca parameters are always | ||||
7046 | // considered written" | ||||
7047 | if (hasAttr({Attribute::InAlloca, Attribute::Preallocated})) { | ||||
7048 | removeKnownBits(NO_WRITES); | ||||
7049 | removeAssumedBits(NO_WRITES); | ||||
7050 | } | ||||
7051 | return AAMemoryBehaviorFloating::manifest(A); | ||||
7052 | } | ||||
7053 | |||||
7054 | /// See AbstractAttribute::trackStatistics() | ||||
7055 | void trackStatistics() const override { | ||||
7056 | if (isAssumedReadNone()) | ||||
7057 | STATS_DECLTRACK_ARG_ATTR(readnone){ static llvm::Statistic NumIRArguments_readnone = {"attributor" , "NumIRArguments_readnone", ("Number of " "arguments" " marked '" "readnone" "'")};; ++(NumIRArguments_readnone); } | ||||
7058 | else if (isAssumedReadOnly()) | ||||
7059 | STATS_DECLTRACK_ARG_ATTR(readonly){ static llvm::Statistic NumIRArguments_readonly = {"attributor" , "NumIRArguments_readonly", ("Number of " "arguments" " marked '" "readonly" "'")};; ++(NumIRArguments_readonly); } | ||||
7060 | else if (isAssumedWriteOnly()) | ||||
7061 | STATS_DECLTRACK_ARG_ATTR(writeonly){ static llvm::Statistic NumIRArguments_writeonly = {"attributor" , "NumIRArguments_writeonly", ("Number of " "arguments" " marked '" "writeonly" "'")};; ++(NumIRArguments_writeonly); } | ||||
7062 | } | ||||
7063 | }; | ||||
7064 | |||||
7065 | struct AAMemoryBehaviorCallSiteArgument final : AAMemoryBehaviorArgument { | ||||
7066 | AAMemoryBehaviorCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
7067 | : AAMemoryBehaviorArgument(IRP, A) {} | ||||
7068 | |||||
7069 | /// See AbstractAttribute::initialize(...). | ||||
7070 | void initialize(Attributor &A) override { | ||||
7071 | // If we don't have an associated attribute this is either a variadic call | ||||
7072 | // or an indirect call, either way, nothing to do here. | ||||
7073 | Argument *Arg = getAssociatedArgument(); | ||||
7074 | if (!Arg) { | ||||
7075 | indicatePessimisticFixpoint(); | ||||
7076 | return; | ||||
7077 | } | ||||
7078 | if (Arg->hasByValAttr()) { | ||||
7079 | addKnownBits(NO_WRITES); | ||||
7080 | removeKnownBits(NO_READS); | ||||
7081 | removeAssumedBits(NO_READS); | ||||
7082 | } | ||||
7083 | AAMemoryBehaviorArgument::initialize(A); | ||||
7084 | if (getAssociatedFunction()->isDeclaration()) | ||||
7085 | indicatePessimisticFixpoint(); | ||||
7086 | } | ||||
7087 | |||||
7088 | /// See AbstractAttribute::updateImpl(...). | ||||
7089 | ChangeStatus updateImpl(Attributor &A) override { | ||||
7090 | // TODO: Once we have call site specific value information we can provide | ||||
7091 | // call site specific liveness liveness information and then it makes | ||||
7092 | // sense to specialize attributes for call sites arguments instead of | ||||
7093 | // redirecting requests to the callee argument. | ||||
7094 | Argument *Arg = getAssociatedArgument(); | ||||
7095 | const IRPosition &ArgPos = IRPosition::argument(*Arg); | ||||
7096 | auto &ArgAA = | ||||
7097 | A.getAAFor<AAMemoryBehavior>(*this, ArgPos, DepClassTy::REQUIRED); | ||||
7098 | return clampStateAndIndicateChange(getState(), ArgAA.getState()); | ||||
7099 | } | ||||
7100 | |||||
7101 | /// See AbstractAttribute::trackStatistics() | ||||
7102 | void trackStatistics() const override { | ||||
7103 | if (isAssumedReadNone()) | ||||
7104 | STATS_DECLTRACK_CSARG_ATTR(readnone){ static llvm::Statistic NumIRCSArguments_readnone = {"attributor" , "NumIRCSArguments_readnone", ("Number of " "call site arguments" " marked '" "readnone" "'")};; ++(NumIRCSArguments_readnone) ; } | ||||
7105 | else if (isAssumedReadOnly()) | ||||
7106 | STATS_DECLTRACK_CSARG_ATTR(readonly){ static llvm::Statistic NumIRCSArguments_readonly = {"attributor" , "NumIRCSArguments_readonly", ("Number of " "call site arguments" " marked '" "readonly" "'")};; ++(NumIRCSArguments_readonly) ; } | ||||
7107 | else if (isAssumedWriteOnly()) | ||||
7108 | STATS_DECLTRACK_CSARG_ATTR(writeonly){ static llvm::Statistic NumIRCSArguments_writeonly = {"attributor" , "NumIRCSArguments_writeonly", ("Number of " "call site arguments" " marked '" "writeonly" "'")};; ++(NumIRCSArguments_writeonly ); } | ||||
7109 | } | ||||
7110 | }; | ||||
7111 | |||||
7112 | /// Memory behavior attribute for a call site return position. | ||||
7113 | struct AAMemoryBehaviorCallSiteReturned final : AAMemoryBehaviorFloating { | ||||
7114 | AAMemoryBehaviorCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
7115 | : AAMemoryBehaviorFloating(IRP, A) {} | ||||
7116 | |||||
7117 | /// See AbstractAttribute::initialize(...). | ||||
7118 | void initialize(Attributor &A) override { | ||||
7119 | AAMemoryBehaviorImpl::initialize(A); | ||||
7120 | Function *F = getAssociatedFunction(); | ||||
7121 | if (!F || F->isDeclaration()) | ||||
7122 | indicatePessimisticFixpoint(); | ||||
7123 | } | ||||
7124 | |||||
7125 | /// See AbstractAttribute::manifest(...). | ||||
7126 | ChangeStatus manifest(Attributor &A) override { | ||||
7127 | // We do not annotate returned values. | ||||
7128 | return ChangeStatus::UNCHANGED; | ||||
7129 | } | ||||
7130 | |||||
7131 | /// See AbstractAttribute::trackStatistics() | ||||
7132 | void trackStatistics() const override {} | ||||
7133 | }; | ||||
7134 | |||||
7135 | /// An AA to represent the memory behavior function attributes. | ||||
7136 | struct AAMemoryBehaviorFunction final : public AAMemoryBehaviorImpl { | ||||
7137 | AAMemoryBehaviorFunction(const IRPosition &IRP, Attributor &A) | ||||
7138 | : AAMemoryBehaviorImpl(IRP, A) {} | ||||
7139 | |||||
7140 | /// See AbstractAttribute::updateImpl(Attributor &A). | ||||
7141 | virtual ChangeStatus updateImpl(Attributor &A) override; | ||||
7142 | |||||
7143 | /// See AbstractAttribute::manifest(...). | ||||
7144 | ChangeStatus manifest(Attributor &A) override { | ||||
7145 | Function &F = cast<Function>(getAnchorValue()); | ||||
7146 | if (isAssumedReadNone()) { | ||||
7147 | F.removeFnAttr(Attribute::ArgMemOnly); | ||||
7148 | F.removeFnAttr(Attribute::InaccessibleMemOnly); | ||||
7149 | F.removeFnAttr(Attribute::InaccessibleMemOrArgMemOnly); | ||||
7150 | } | ||||
7151 | return AAMemoryBehaviorImpl::manifest(A); | ||||
7152 | } | ||||
7153 | |||||
7154 | /// See AbstractAttribute::trackStatistics() | ||||
7155 | void trackStatistics() const override { | ||||
7156 | if (isAssumedReadNone()) | ||||
7157 | STATS_DECLTRACK_FN_ATTR(readnone){ static llvm::Statistic NumIRFunction_readnone = {"attributor" , "NumIRFunction_readnone", ("Number of " "functions" " marked '" "readnone" "'")};; ++(NumIRFunction_readnone); } | ||||
7158 | else if (isAssumedReadOnly()) | ||||
7159 | STATS_DECLTRACK_FN_ATTR(readonly){ static llvm::Statistic NumIRFunction_readonly = {"attributor" , "NumIRFunction_readonly", ("Number of " "functions" " marked '" "readonly" "'")};; ++(NumIRFunction_readonly); } | ||||
7160 | else if (isAssumedWriteOnly()) | ||||
7161 | STATS_DECLTRACK_FN_ATTR(writeonly){ static llvm::Statistic NumIRFunction_writeonly = {"attributor" , "NumIRFunction_writeonly", ("Number of " "functions" " marked '" "writeonly" "'")};; ++(NumIRFunction_writeonly); } | ||||
7162 | } | ||||
7163 | }; | ||||
7164 | |||||
7165 | /// AAMemoryBehavior attribute for call sites. | ||||
7166 | struct AAMemoryBehaviorCallSite final : AAMemoryBehaviorImpl { | ||||
7167 | AAMemoryBehaviorCallSite(const IRPosition &IRP, Attributor &A) | ||||
7168 | : AAMemoryBehaviorImpl(IRP, A) {} | ||||
7169 | |||||
7170 | /// See AbstractAttribute::initialize(...). | ||||
7171 | void initialize(Attributor &A) override { | ||||
7172 | AAMemoryBehaviorImpl::initialize(A); | ||||
7173 | Function *F = getAssociatedFunction(); | ||||
7174 | if (!F || F->isDeclaration()) | ||||
7175 | indicatePessimisticFixpoint(); | ||||
7176 | } | ||||
7177 | |||||
7178 | /// See AbstractAttribute::updateImpl(...). | ||||
7179 | ChangeStatus updateImpl(Attributor &A) override { | ||||
7180 | // TODO: Once we have call site specific value information we can provide | ||||
7181 | // call site specific liveness liveness information and then it makes | ||||
7182 | // sense to specialize attributes for call sites arguments instead of | ||||
7183 | // redirecting requests to the callee argument. | ||||
7184 | Function *F = getAssociatedFunction(); | ||||
7185 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
7186 | auto &FnAA = | ||||
7187 | A.getAAFor<AAMemoryBehavior>(*this, FnPos, DepClassTy::REQUIRED); | ||||
7188 | return clampStateAndIndicateChange(getState(), FnAA.getState()); | ||||
7189 | } | ||||
7190 | |||||
7191 | /// See AbstractAttribute::trackStatistics() | ||||
7192 | void trackStatistics() const override { | ||||
7193 | if (isAssumedReadNone()) | ||||
7194 | STATS_DECLTRACK_CS_ATTR(readnone){ static llvm::Statistic NumIRCS_readnone = {"attributor", "NumIRCS_readnone" , ("Number of " "call site" " marked '" "readnone" "'")};; ++ (NumIRCS_readnone); } | ||||
7195 | else if (isAssumedReadOnly()) | ||||
7196 | STATS_DECLTRACK_CS_ATTR(readonly){ static llvm::Statistic NumIRCS_readonly = {"attributor", "NumIRCS_readonly" , ("Number of " "call site" " marked '" "readonly" "'")};; ++ (NumIRCS_readonly); } | ||||
7197 | else if (isAssumedWriteOnly()) | ||||
7198 | STATS_DECLTRACK_CS_ATTR(writeonly){ static llvm::Statistic NumIRCS_writeonly = {"attributor", "NumIRCS_writeonly" , ("Number of " "call site" " marked '" "writeonly" "'")};; ++ (NumIRCS_writeonly); } | ||||
7199 | } | ||||
7200 | }; | ||||
7201 | |||||
7202 | ChangeStatus AAMemoryBehaviorFunction::updateImpl(Attributor &A) { | ||||
7203 | |||||
7204 | // The current assumed state used to determine a change. | ||||
7205 | auto AssumedState = getAssumed(); | ||||
7206 | |||||
7207 | auto CheckRWInst = [&](Instruction &I) { | ||||
7208 | // If the instruction has an own memory behavior state, use it to restrict | ||||
7209 | // the local state. No further analysis is required as the other memory | ||||
7210 | // state is as optimistic as it gets. | ||||
7211 | if (const auto *CB = dyn_cast<CallBase>(&I)) { | ||||
7212 | const auto &MemBehaviorAA = A.getAAFor<AAMemoryBehavior>( | ||||
7213 | *this, IRPosition::callsite_function(*CB), DepClassTy::REQUIRED); | ||||
7214 | intersectAssumedBits(MemBehaviorAA.getAssumed()); | ||||
7215 | return !isAtFixpoint(); | ||||
7216 | } | ||||
7217 | |||||
7218 | // Remove access kind modifiers if necessary. | ||||
7219 | if (I.mayReadFromMemory()) | ||||
7220 | removeAssumedBits(NO_READS); | ||||
7221 | if (I.mayWriteToMemory()) | ||||
7222 | removeAssumedBits(NO_WRITES); | ||||
7223 | return !isAtFixpoint(); | ||||
7224 | }; | ||||
7225 | |||||
7226 | bool UsedAssumedInformation = false; | ||||
7227 | if (!A.checkForAllReadWriteInstructions(CheckRWInst, *this, | ||||
7228 | UsedAssumedInformation)) | ||||
7229 | return indicatePessimisticFixpoint(); | ||||
7230 | |||||
7231 | return (AssumedState != getAssumed()) ? ChangeStatus::CHANGED | ||||
7232 | : ChangeStatus::UNCHANGED; | ||||
7233 | } | ||||
7234 | |||||
7235 | ChangeStatus AAMemoryBehaviorFloating::updateImpl(Attributor &A) { | ||||
7236 | |||||
7237 | const IRPosition &IRP = getIRPosition(); | ||||
7238 | const IRPosition &FnPos = IRPosition::function_scope(IRP); | ||||
7239 | AAMemoryBehavior::StateType &S = getState(); | ||||
7240 | |||||
7241 | // First, check the function scope. We take the known information and we avoid | ||||
7242 | // work if the assumed information implies the current assumed information for | ||||
7243 | // this attribute. This is a valid for all but byval arguments. | ||||
7244 | Argument *Arg = IRP.getAssociatedArgument(); | ||||
7245 | AAMemoryBehavior::base_t FnMemAssumedState = | ||||
7246 | AAMemoryBehavior::StateType::getWorstState(); | ||||
7247 | if (!Arg || !Arg->hasByValAttr()) { | ||||
7248 | const auto &FnMemAA = | ||||
7249 | A.getAAFor<AAMemoryBehavior>(*this, FnPos, DepClassTy::OPTIONAL); | ||||
7250 | FnMemAssumedState = FnMemAA.getAssumed(); | ||||
7251 | S.addKnownBits(FnMemAA.getKnown()); | ||||
7252 | if ((S.getAssumed() & FnMemAA.getAssumed()) == S.getAssumed()) | ||||
7253 | return ChangeStatus::UNCHANGED; | ||||
7254 | } | ||||
7255 | |||||
7256 | // The current assumed state used to determine a change. | ||||
7257 | auto AssumedState = S.getAssumed(); | ||||
7258 | |||||
7259 | // Make sure the value is not captured (except through "return"), if | ||||
7260 | // it is, any information derived would be irrelevant anyway as we cannot | ||||
7261 | // check the potential aliases introduced by the capture. However, no need | ||||
7262 | // to fall back to anythign less optimistic than the function state. | ||||
7263 | const auto &ArgNoCaptureAA = | ||||
7264 | A.getAAFor<AANoCapture>(*this, IRP, DepClassTy::OPTIONAL); | ||||
7265 | if (!ArgNoCaptureAA.isAssumedNoCaptureMaybeReturned()) { | ||||
7266 | S.intersectAssumedBits(FnMemAssumedState); | ||||
7267 | return (AssumedState != getAssumed()) ? ChangeStatus::CHANGED | ||||
7268 | : ChangeStatus::UNCHANGED; | ||||
7269 | } | ||||
7270 | |||||
7271 | // Visit and expand uses until all are analyzed or a fixpoint is reached. | ||||
7272 | auto UsePred = [&](const Use &U, bool &Follow) -> bool { | ||||
7273 | Instruction *UserI = cast<Instruction>(U.getUser()); | ||||
7274 | LLVM_DEBUG(dbgs() << "[AAMemoryBehavior] Use: " << *U << " in " << *UserIdo { } while (false) | ||||
7275 | << " \n")do { } while (false); | ||||
7276 | |||||
7277 | // Droppable users, e.g., llvm::assume does not actually perform any action. | ||||
7278 | if (UserI->isDroppable()) | ||||
7279 | return true; | ||||
7280 | |||||
7281 | // Check if the users of UserI should also be visited. | ||||
7282 | Follow = followUsersOfUseIn(A, U, UserI); | ||||
7283 | |||||
7284 | // If UserI might touch memory we analyze the use in detail. | ||||
7285 | if (UserI->mayReadOrWriteMemory()) | ||||
7286 | analyzeUseIn(A, U, UserI); | ||||
7287 | |||||
7288 | return !isAtFixpoint(); | ||||
7289 | }; | ||||
7290 | |||||
7291 | if (!A.checkForAllUses(UsePred, *this, getAssociatedValue())) | ||||
7292 | return indicatePessimisticFixpoint(); | ||||
7293 | |||||
7294 | return (AssumedState != getAssumed()) ? ChangeStatus::CHANGED | ||||
7295 | : ChangeStatus::UNCHANGED; | ||||
7296 | } | ||||
7297 | |||||
7298 | bool AAMemoryBehaviorFloating::followUsersOfUseIn(Attributor &A, const Use &U, | ||||
7299 | const Instruction *UserI) { | ||||
7300 | // The loaded value is unrelated to the pointer argument, no need to | ||||
7301 | // follow the users of the load. | ||||
7302 | if (isa<LoadInst>(UserI)) | ||||
7303 | return false; | ||||
7304 | |||||
7305 | // By default we follow all uses assuming UserI might leak information on U, | ||||
7306 | // we have special handling for call sites operands though. | ||||
7307 | const auto *CB = dyn_cast<CallBase>(UserI); | ||||
7308 | if (!CB || !CB->isArgOperand(&U)) | ||||
7309 | return true; | ||||
7310 | |||||
7311 | // If the use is a call argument known not to be captured, the users of | ||||
7312 | // the call do not need to be visited because they have to be unrelated to | ||||
7313 | // the input. Note that this check is not trivial even though we disallow | ||||
7314 | // general capturing of the underlying argument. The reason is that the | ||||
7315 | // call might the argument "through return", which we allow and for which we | ||||
7316 | // need to check call users. | ||||
7317 | if (U.get()->getType()->isPointerTy()) { | ||||
7318 | unsigned ArgNo = CB->getArgOperandNo(&U); | ||||
7319 | const auto &ArgNoCaptureAA = A.getAAFor<AANoCapture>( | ||||
7320 | *this, IRPosition::callsite_argument(*CB, ArgNo), DepClassTy::OPTIONAL); | ||||
7321 | return !ArgNoCaptureAA.isAssumedNoCapture(); | ||||
7322 | } | ||||
7323 | |||||
7324 | return true; | ||||
7325 | } | ||||
7326 | |||||
7327 | void AAMemoryBehaviorFloating::analyzeUseIn(Attributor &A, const Use &U, | ||||
7328 | const Instruction *UserI) { | ||||
7329 | assert(UserI->mayReadOrWriteMemory())(static_cast<void> (0)); | ||||
7330 | |||||
7331 | switch (UserI->getOpcode()) { | ||||
7332 | default: | ||||
7333 | // TODO: Handle all atomics and other side-effect operations we know of. | ||||
7334 | break; | ||||
7335 | case Instruction::Load: | ||||
7336 | // Loads cause the NO_READS property to disappear. | ||||
7337 | removeAssumedBits(NO_READS); | ||||
7338 | return; | ||||
7339 | |||||
7340 | case Instruction::Store: | ||||
7341 | // Stores cause the NO_WRITES property to disappear if the use is the | ||||
7342 | // pointer operand. Note that we do assume that capturing was taken care of | ||||
7343 | // somewhere else. | ||||
7344 | if (cast<StoreInst>(UserI)->getPointerOperand() == U.get()) | ||||
7345 | removeAssumedBits(NO_WRITES); | ||||
7346 | return; | ||||
7347 | |||||
7348 | case Instruction::Call: | ||||
7349 | case Instruction::CallBr: | ||||
7350 | case Instruction::Invoke: { | ||||
7351 | // For call sites we look at the argument memory behavior attribute (this | ||||
7352 | // could be recursive!) in order to restrict our own state. | ||||
7353 | const auto *CB = cast<CallBase>(UserI); | ||||
7354 | |||||
7355 | // Give up on operand bundles. | ||||
7356 | if (CB->isBundleOperand(&U)) { | ||||
7357 | indicatePessimisticFixpoint(); | ||||
7358 | return; | ||||
7359 | } | ||||
7360 | |||||
7361 | // Calling a function does read the function pointer, maybe write it if the | ||||
7362 | // function is self-modifying. | ||||
7363 | if (CB->isCallee(&U)) { | ||||
7364 | removeAssumedBits(NO_READS); | ||||
7365 | break; | ||||
7366 | } | ||||
7367 | |||||
7368 | // Adjust the possible access behavior based on the information on the | ||||
7369 | // argument. | ||||
7370 | IRPosition Pos; | ||||
7371 | if (U.get()->getType()->isPointerTy()) | ||||
7372 | Pos = IRPosition::callsite_argument(*CB, CB->getArgOperandNo(&U)); | ||||
7373 | else | ||||
7374 | Pos = IRPosition::callsite_function(*CB); | ||||
7375 | const auto &MemBehaviorAA = | ||||
7376 | A.getAAFor<AAMemoryBehavior>(*this, Pos, DepClassTy::OPTIONAL); | ||||
7377 | // "assumed" has at most the same bits as the MemBehaviorAA assumed | ||||
7378 | // and at least "known". | ||||
7379 | intersectAssumedBits(MemBehaviorAA.getAssumed()); | ||||
7380 | return; | ||||
7381 | } | ||||
7382 | }; | ||||
7383 | |||||
7384 | // Generally, look at the "may-properties" and adjust the assumed state if we | ||||
7385 | // did not trigger special handling before. | ||||
7386 | if (UserI->mayReadFromMemory()) | ||||
7387 | removeAssumedBits(NO_READS); | ||||
7388 | if (UserI->mayWriteToMemory()) | ||||
7389 | removeAssumedBits(NO_WRITES); | ||||
7390 | } | ||||
7391 | |||||
7392 | /// -------------------- Memory Locations Attributes --------------------------- | ||||
7393 | /// Includes read-none, argmemonly, inaccessiblememonly, | ||||
7394 | /// inaccessiblememorargmemonly | ||||
7395 | /// ---------------------------------------------------------------------------- | ||||
7396 | |||||
7397 | std::string AAMemoryLocation::getMemoryLocationsAsStr( | ||||
7398 | AAMemoryLocation::MemoryLocationsKind MLK) { | ||||
7399 | if (0 == (MLK & AAMemoryLocation::NO_LOCATIONS)) | ||||
7400 | return "all memory"; | ||||
7401 | if (MLK == AAMemoryLocation::NO_LOCATIONS) | ||||
7402 | return "no memory"; | ||||
7403 | std::string S = "memory:"; | ||||
7404 | if (0 == (MLK & AAMemoryLocation::NO_LOCAL_MEM)) | ||||
7405 | S += "stack,"; | ||||
7406 | if (0 == (MLK & AAMemoryLocation::NO_CONST_MEM)) | ||||
7407 | S += "constant,"; | ||||
7408 | if (0 == (MLK & AAMemoryLocation::NO_GLOBAL_INTERNAL_MEM)) | ||||
7409 | S += "internal global,"; | ||||
7410 | if (0 == (MLK & AAMemoryLocation::NO_GLOBAL_EXTERNAL_MEM)) | ||||
7411 | S += "external global,"; | ||||
7412 | if (0 == (MLK & AAMemoryLocation::NO_ARGUMENT_MEM)) | ||||
7413 | S += "argument,"; | ||||
7414 | if (0 == (MLK & AAMemoryLocation::NO_INACCESSIBLE_MEM)) | ||||
7415 | S += "inaccessible,"; | ||||
7416 | if (0 == (MLK & AAMemoryLocation::NO_MALLOCED_MEM)) | ||||
7417 | S += "malloced,"; | ||||
7418 | if (0 == (MLK & AAMemoryLocation::NO_UNKOWN_MEM)) | ||||
7419 | S += "unknown,"; | ||||
7420 | S.pop_back(); | ||||
7421 | return S; | ||||
7422 | } | ||||
7423 | |||||
7424 | namespace { | ||||
7425 | struct AAMemoryLocationImpl : public AAMemoryLocation { | ||||
7426 | |||||
7427 | AAMemoryLocationImpl(const IRPosition &IRP, Attributor &A) | ||||
7428 | : AAMemoryLocation(IRP, A), Allocator(A.Allocator) { | ||||
7429 | for (unsigned u = 0; u < llvm::CTLog2<VALID_STATE>(); ++u) | ||||
7430 | AccessKind2Accesses[u] = nullptr; | ||||
7431 | } | ||||
7432 | |||||
7433 | ~AAMemoryLocationImpl() { | ||||
7434 | // The AccessSets are allocated via a BumpPtrAllocator, we call | ||||
7435 | // the destructor manually. | ||||
7436 | for (unsigned u = 0; u < llvm::CTLog2<VALID_STATE>(); ++u) | ||||
7437 | if (AccessKind2Accesses[u]) | ||||
7438 | AccessKind2Accesses[u]->~AccessSet(); | ||||
7439 | } | ||||
7440 | |||||
7441 | /// See AbstractAttribute::initialize(...). | ||||
7442 | void initialize(Attributor &A) override { | ||||
7443 | intersectAssumedBits(BEST_STATE); | ||||
7444 | getKnownStateFromValue(A, getIRPosition(), getState()); | ||||
7445 | AAMemoryLocation::initialize(A); | ||||
7446 | } | ||||
7447 | |||||
7448 | /// Return the memory behavior information encoded in the IR for \p IRP. | ||||
7449 | static void getKnownStateFromValue(Attributor &A, const IRPosition &IRP, | ||||
7450 | BitIntegerState &State, | ||||
7451 | bool IgnoreSubsumingPositions = false) { | ||||
7452 | // For internal functions we ignore `argmemonly` and | ||||
7453 | // `inaccessiblememorargmemonly` as we might break it via interprocedural | ||||
7454 | // constant propagation. It is unclear if this is the best way but it is | ||||
7455 | // unlikely this will cause real performance problems. If we are deriving | ||||
7456 | // attributes for the anchor function we even remove the attribute in | ||||
7457 | // addition to ignoring it. | ||||
7458 | bool UseArgMemOnly = true; | ||||
7459 | Function *AnchorFn = IRP.getAnchorScope(); | ||||
7460 | if (AnchorFn && A.isRunOn(*AnchorFn)) | ||||
7461 | UseArgMemOnly = !AnchorFn->hasLocalLinkage(); | ||||
7462 | |||||
7463 | SmallVector<Attribute, 2> Attrs; | ||||
7464 | IRP.getAttrs(AttrKinds, Attrs, IgnoreSubsumingPositions); | ||||
7465 | for (const Attribute &Attr : Attrs) { | ||||
7466 | switch (Attr.getKindAsEnum()) { | ||||
7467 | case Attribute::ReadNone: | ||||
7468 | State.addKnownBits(NO_LOCAL_MEM | NO_CONST_MEM); | ||||
7469 | break; | ||||
7470 | case Attribute::InaccessibleMemOnly: | ||||
7471 | State.addKnownBits(inverseLocation(NO_INACCESSIBLE_MEM, true, true)); | ||||
7472 | break; | ||||
7473 | case Attribute::ArgMemOnly: | ||||
7474 | if (UseArgMemOnly) | ||||
7475 | State.addKnownBits(inverseLocation(NO_ARGUMENT_MEM, true, true)); | ||||
7476 | else | ||||
7477 | IRP.removeAttrs({Attribute::ArgMemOnly}); | ||||
7478 | break; | ||||
7479 | case Attribute::InaccessibleMemOrArgMemOnly: | ||||
7480 | if (UseArgMemOnly) | ||||
7481 | State.addKnownBits(inverseLocation( | ||||
7482 | NO_INACCESSIBLE_MEM | NO_ARGUMENT_MEM, true, true)); | ||||
7483 | else | ||||
7484 | IRP.removeAttrs({Attribute::InaccessibleMemOrArgMemOnly}); | ||||
7485 | break; | ||||
7486 | default: | ||||
7487 | llvm_unreachable("Unexpected attribute!")__builtin_unreachable(); | ||||
7488 | } | ||||
7489 | } | ||||
7490 | } | ||||
7491 | |||||
7492 | /// See AbstractAttribute::getDeducedAttributes(...). | ||||
7493 | void getDeducedAttributes(LLVMContext &Ctx, | ||||
7494 | SmallVectorImpl<Attribute> &Attrs) const override { | ||||
7495 | assert(Attrs.size() == 0)(static_cast<void> (0)); | ||||
7496 | if (isAssumedReadNone()) { | ||||
7497 | Attrs.push_back(Attribute::get(Ctx, Attribute::ReadNone)); | ||||
7498 | } else if (getIRPosition().getPositionKind() == IRPosition::IRP_FUNCTION) { | ||||
7499 | if (isAssumedInaccessibleMemOnly()) | ||||
7500 | Attrs.push_back(Attribute::get(Ctx, Attribute::InaccessibleMemOnly)); | ||||
7501 | else if (isAssumedArgMemOnly()) | ||||
7502 | Attrs.push_back(Attribute::get(Ctx, Attribute::ArgMemOnly)); | ||||
7503 | else if (isAssumedInaccessibleOrArgMemOnly()) | ||||
7504 | Attrs.push_back( | ||||
7505 | Attribute::get(Ctx, Attribute::InaccessibleMemOrArgMemOnly)); | ||||
7506 | } | ||||
7507 | assert(Attrs.size() <= 1)(static_cast<void> (0)); | ||||
7508 | } | ||||
7509 | |||||
7510 | /// See AbstractAttribute::manifest(...). | ||||
7511 | ChangeStatus manifest(Attributor &A) override { | ||||
7512 | const IRPosition &IRP = getIRPosition(); | ||||
7513 | |||||
7514 | // Check if we would improve the existing attributes first. | ||||
7515 | SmallVector<Attribute, 4> DeducedAttrs; | ||||
7516 | getDeducedAttributes(IRP.getAnchorValue().getContext(), DeducedAttrs); | ||||
7517 | if (llvm::all_of(DeducedAttrs, [&](const Attribute &Attr) { | ||||
7518 | return IRP.hasAttr(Attr.getKindAsEnum(), | ||||
7519 | /* IgnoreSubsumingPositions */ true); | ||||
7520 | })) | ||||
7521 | return ChangeStatus::UNCHANGED; | ||||
7522 | |||||
7523 | // Clear existing attributes. | ||||
7524 | IRP.removeAttrs(AttrKinds); | ||||
7525 | if (isAssumedReadNone()) | ||||
7526 | IRP.removeAttrs(AAMemoryBehaviorImpl::AttrKinds); | ||||
7527 | |||||
7528 | // Use the generic manifest method. | ||||
7529 | return IRAttribute::manifest(A); | ||||
7530 | } | ||||
7531 | |||||
7532 | /// See AAMemoryLocation::checkForAllAccessesToMemoryKind(...). | ||||
7533 | bool checkForAllAccessesToMemoryKind( | ||||
7534 | function_ref<bool(const Instruction *, const Value *, AccessKind, | ||||
7535 | MemoryLocationsKind)> | ||||
7536 | Pred, | ||||
7537 | MemoryLocationsKind RequestedMLK) const override { | ||||
7538 | if (!isValidState()) | ||||
7539 | return false; | ||||
7540 | |||||
7541 | MemoryLocationsKind AssumedMLK = getAssumedNotAccessedLocation(); | ||||
7542 | if (AssumedMLK == NO_LOCATIONS) | ||||
7543 | return true; | ||||
7544 | |||||
7545 | unsigned Idx = 0; | ||||
7546 | for (MemoryLocationsKind CurMLK = 1; CurMLK < NO_LOCATIONS; | ||||
7547 | CurMLK *= 2, ++Idx) { | ||||
7548 | if (CurMLK & RequestedMLK) | ||||
7549 | continue; | ||||
7550 | |||||
7551 | if (const AccessSet *Accesses = AccessKind2Accesses[Idx]) | ||||
7552 | for (const AccessInfo &AI : *Accesses) | ||||
7553 | if (!Pred(AI.I, AI.Ptr, AI.Kind, CurMLK)) | ||||
7554 | return false; | ||||
7555 | } | ||||
7556 | |||||
7557 | return true; | ||||
7558 | } | ||||
7559 | |||||
7560 | ChangeStatus indicatePessimisticFixpoint() override { | ||||
7561 | // If we give up and indicate a pessimistic fixpoint this instruction will | ||||
7562 | // become an access for all potential access kinds: | ||||
7563 | // TODO: Add pointers for argmemonly and globals to improve the results of | ||||
7564 | // checkForAllAccessesToMemoryKind. | ||||
7565 | bool Changed = false; | ||||
7566 | MemoryLocationsKind KnownMLK = getKnown(); | ||||
7567 | Instruction *I = dyn_cast<Instruction>(&getAssociatedValue()); | ||||
7568 | for (MemoryLocationsKind CurMLK = 1; CurMLK < NO_LOCATIONS; CurMLK *= 2) | ||||
7569 | if (!(CurMLK & KnownMLK)) | ||||
7570 | updateStateAndAccessesMap(getState(), CurMLK, I, nullptr, Changed, | ||||
7571 | getAccessKindFromInst(I)); | ||||
7572 | return AAMemoryLocation::indicatePessimisticFixpoint(); | ||||
7573 | } | ||||
7574 | |||||
7575 | protected: | ||||
7576 | /// Helper struct to tie together an instruction that has a read or write | ||||
7577 | /// effect with the pointer it accesses (if any). | ||||
7578 | struct AccessInfo { | ||||
7579 | |||||
7580 | /// The instruction that caused the access. | ||||
7581 | const Instruction *I; | ||||
7582 | |||||
7583 | /// The base pointer that is accessed, or null if unknown. | ||||
7584 | const Value *Ptr; | ||||
7585 | |||||
7586 | /// The kind of access (read/write/read+write). | ||||
7587 | AccessKind Kind; | ||||
7588 | |||||
7589 | bool operator==(const AccessInfo &RHS) const { | ||||
7590 | return I == RHS.I && Ptr == RHS.Ptr && Kind == RHS.Kind; | ||||
7591 | } | ||||
7592 | bool operator()(const AccessInfo &LHS, const AccessInfo &RHS) const { | ||||
7593 | if (LHS.I != RHS.I) | ||||
7594 | return LHS.I < RHS.I; | ||||
7595 | if (LHS.Ptr != RHS.Ptr) | ||||
7596 | return LHS.Ptr < RHS.Ptr; | ||||
7597 | if (LHS.Kind != RHS.Kind) | ||||
7598 | return LHS.Kind < RHS.Kind; | ||||
7599 | return false; | ||||
7600 | } | ||||
7601 | }; | ||||
7602 | |||||
7603 | /// Mapping from *single* memory location kinds, e.g., LOCAL_MEM with the | ||||
7604 | /// value of NO_LOCAL_MEM, to the accesses encountered for this memory kind. | ||||
7605 | using AccessSet = SmallSet<AccessInfo, 2, AccessInfo>; | ||||
7606 | AccessSet *AccessKind2Accesses[llvm::CTLog2<VALID_STATE>()]; | ||||
7607 | |||||
7608 | /// Categorize the pointer arguments of CB that might access memory in | ||||
7609 | /// AccessedLoc and update the state and access map accordingly. | ||||
7610 | void | ||||
7611 | categorizeArgumentPointerLocations(Attributor &A, CallBase &CB, | ||||
7612 | AAMemoryLocation::StateType &AccessedLocs, | ||||
7613 | bool &Changed); | ||||
7614 | |||||
7615 | /// Return the kind(s) of location that may be accessed by \p V. | ||||
7616 | AAMemoryLocation::MemoryLocationsKind | ||||
7617 | categorizeAccessedLocations(Attributor &A, Instruction &I, bool &Changed); | ||||
7618 | |||||
7619 | /// Return the access kind as determined by \p I. | ||||
7620 | AccessKind getAccessKindFromInst(const Instruction *I) { | ||||
7621 | AccessKind AK = READ_WRITE; | ||||
7622 | if (I) { | ||||
7623 | AK = I->mayReadFromMemory() ? READ : NONE; | ||||
7624 | AK = AccessKind(AK | (I->mayWriteToMemory() ? WRITE : NONE)); | ||||
7625 | } | ||||
7626 | return AK; | ||||
7627 | } | ||||
7628 | |||||
7629 | /// Update the state \p State and the AccessKind2Accesses given that \p I is | ||||
7630 | /// an access of kind \p AK to a \p MLK memory location with the access | ||||
7631 | /// pointer \p Ptr. | ||||
7632 | void updateStateAndAccessesMap(AAMemoryLocation::StateType &State, | ||||
7633 | MemoryLocationsKind MLK, const Instruction *I, | ||||
7634 | const Value *Ptr, bool &Changed, | ||||
7635 | AccessKind AK = READ_WRITE) { | ||||
7636 | |||||
7637 | assert(isPowerOf2_32(MLK) && "Expected a single location set!")(static_cast<void> (0)); | ||||
7638 | auto *&Accesses = AccessKind2Accesses[llvm::Log2_32(MLK)]; | ||||
7639 | if (!Accesses) | ||||
7640 | Accesses = new (Allocator) AccessSet(); | ||||
7641 | Changed |= Accesses->insert(AccessInfo{I, Ptr, AK}).second; | ||||
7642 | State.removeAssumedBits(MLK); | ||||
7643 | } | ||||
7644 | |||||
7645 | /// Determine the underlying locations kinds for \p Ptr, e.g., globals or | ||||
7646 | /// arguments, and update the state and access map accordingly. | ||||
7647 | void categorizePtrValue(Attributor &A, const Instruction &I, const Value &Ptr, | ||||
7648 | AAMemoryLocation::StateType &State, bool &Changed); | ||||
7649 | |||||
7650 | /// Used to allocate access sets. | ||||
7651 | BumpPtrAllocator &Allocator; | ||||
7652 | |||||
7653 | /// The set of IR attributes AAMemoryLocation deals with. | ||||
7654 | static const Attribute::AttrKind AttrKinds[4]; | ||||
7655 | }; | ||||
7656 | |||||
7657 | const Attribute::AttrKind AAMemoryLocationImpl::AttrKinds[] = { | ||||
7658 | Attribute::ReadNone, Attribute::InaccessibleMemOnly, Attribute::ArgMemOnly, | ||||
7659 | Attribute::InaccessibleMemOrArgMemOnly}; | ||||
7660 | |||||
7661 | void AAMemoryLocationImpl::categorizePtrValue( | ||||
7662 | Attributor &A, const Instruction &I, const Value &Ptr, | ||||
7663 | AAMemoryLocation::StateType &State, bool &Changed) { | ||||
7664 | LLVM_DEBUG(dbgs() << "[AAMemoryLocation] Categorize pointer locations for "do { } while (false) | ||||
7665 | << Ptr << " ["do { } while (false) | ||||
7666 | << getMemoryLocationsAsStr(State.getAssumed()) << "]\n")do { } while (false); | ||||
7667 | |||||
7668 | SmallVector<Value *, 8> Objects; | ||||
7669 | if (!AA::getAssumedUnderlyingObjects(A, Ptr, Objects, *this, &I)) { | ||||
7670 | LLVM_DEBUG(do { } while (false) | ||||
7671 | dbgs() << "[AAMemoryLocation] Pointer locations not categorized\n")do { } while (false); | ||||
7672 | updateStateAndAccessesMap(State, NO_UNKOWN_MEM, &I, nullptr, Changed, | ||||
7673 | getAccessKindFromInst(&I)); | ||||
7674 | return; | ||||
7675 | } | ||||
7676 | |||||
7677 | for (Value *Obj : Objects) { | ||||
7678 | // TODO: recognize the TBAA used for constant accesses. | ||||
7679 | MemoryLocationsKind MLK = NO_LOCATIONS; | ||||
7680 | assert(!isa<GEPOperator>(Obj) && "GEPs should have been stripped.")(static_cast<void> (0)); | ||||
7681 | if (isa<UndefValue>(Obj)) | ||||
7682 | continue; | ||||
7683 | if (isa<Argument>(Obj)) { | ||||
7684 | // TODO: For now we do not treat byval arguments as local copies performed | ||||
7685 | // on the call edge, though, we should. To make that happen we need to | ||||
7686 | // teach various passes, e.g., DSE, about the copy effect of a byval. That | ||||
7687 | // would also allow us to mark functions only accessing byval arguments as | ||||
7688 | // readnone again, atguably their acceses have no effect outside of the | ||||
7689 | // function, like accesses to allocas. | ||||
7690 | MLK = NO_ARGUMENT_MEM; | ||||
7691 | } else if (auto *GV = dyn_cast<GlobalValue>(Obj)) { | ||||
7692 | // Reading constant memory is not treated as a read "effect" by the | ||||
7693 | // function attr pass so we won't neither. Constants defined by TBAA are | ||||
7694 | // similar. (We know we do not write it because it is constant.) | ||||
7695 | if (auto *GVar = dyn_cast<GlobalVariable>(GV)) | ||||
7696 | if (GVar->isConstant()) | ||||
7697 | continue; | ||||
7698 | |||||
7699 | if (GV->hasLocalLinkage()) | ||||
7700 | MLK = NO_GLOBAL_INTERNAL_MEM; | ||||
7701 | else | ||||
7702 | MLK = NO_GLOBAL_EXTERNAL_MEM; | ||||
7703 | } else if (isa<ConstantPointerNull>(Obj) && | ||||
7704 | !NullPointerIsDefined(getAssociatedFunction(), | ||||
7705 | Ptr.getType()->getPointerAddressSpace())) { | ||||
7706 | continue; | ||||
7707 | } else if (isa<AllocaInst>(Obj)) { | ||||
7708 | MLK = NO_LOCAL_MEM; | ||||
7709 | } else if (const auto *CB = dyn_cast<CallBase>(Obj)) { | ||||
7710 | const auto &NoAliasAA = A.getAAFor<AANoAlias>( | ||||
7711 | *this, IRPosition::callsite_returned(*CB), DepClassTy::OPTIONAL); | ||||
7712 | if (NoAliasAA.isAssumedNoAlias()) | ||||
7713 | MLK = NO_MALLOCED_MEM; | ||||
7714 | else | ||||
7715 | MLK = NO_UNKOWN_MEM; | ||||
7716 | } else { | ||||
7717 | MLK = NO_UNKOWN_MEM; | ||||
7718 | } | ||||
7719 | |||||
7720 | assert(MLK != NO_LOCATIONS && "No location specified!")(static_cast<void> (0)); | ||||
7721 | LLVM_DEBUG(dbgs() << "[AAMemoryLocation] Ptr value can be categorized: "do { } while (false) | ||||
7722 | << *Obj << " -> " << getMemoryLocationsAsStr(MLK)do { } while (false) | ||||
7723 | << "\n")do { } while (false); | ||||
7724 | updateStateAndAccessesMap(getState(), MLK, &I, Obj, Changed, | ||||
7725 | getAccessKindFromInst(&I)); | ||||
7726 | } | ||||
7727 | |||||
7728 | LLVM_DEBUG(do { } while (false) | ||||
7729 | dbgs() << "[AAMemoryLocation] Accessed locations with pointer locations: "do { } while (false) | ||||
7730 | << getMemoryLocationsAsStr(State.getAssumed()) << "\n")do { } while (false); | ||||
7731 | } | ||||
7732 | |||||
7733 | void AAMemoryLocationImpl::categorizeArgumentPointerLocations( | ||||
7734 | Attributor &A, CallBase &CB, AAMemoryLocation::StateType &AccessedLocs, | ||||
7735 | bool &Changed) { | ||||
7736 | for (unsigned ArgNo = 0, E = CB.getNumArgOperands(); ArgNo < E; ++ArgNo) { | ||||
7737 | |||||
7738 | // Skip non-pointer arguments. | ||||
7739 | const Value *ArgOp = CB.getArgOperand(ArgNo); | ||||
7740 | if (!ArgOp->getType()->isPtrOrPtrVectorTy()) | ||||
7741 | continue; | ||||
7742 | |||||
7743 | // Skip readnone arguments. | ||||
7744 | const IRPosition &ArgOpIRP = IRPosition::callsite_argument(CB, ArgNo); | ||||
7745 | const auto &ArgOpMemLocationAA = | ||||
7746 | A.getAAFor<AAMemoryBehavior>(*this, ArgOpIRP, DepClassTy::OPTIONAL); | ||||
7747 | |||||
7748 | if (ArgOpMemLocationAA.isAssumedReadNone()) | ||||
7749 | continue; | ||||
7750 | |||||
7751 | // Categorize potentially accessed pointer arguments as if there was an | ||||
7752 | // access instruction with them as pointer. | ||||
7753 | categorizePtrValue(A, CB, *ArgOp, AccessedLocs, Changed); | ||||
7754 | } | ||||
7755 | } | ||||
7756 | |||||
7757 | AAMemoryLocation::MemoryLocationsKind | ||||
7758 | AAMemoryLocationImpl::categorizeAccessedLocations(Attributor &A, Instruction &I, | ||||
7759 | bool &Changed) { | ||||
7760 | LLVM_DEBUG(dbgs() << "[AAMemoryLocation] Categorize accessed locations for "do { } while (false) | ||||
7761 | << I << "\n")do { } while (false); | ||||
7762 | |||||
7763 | AAMemoryLocation::StateType AccessedLocs; | ||||
7764 | AccessedLocs.intersectAssumedBits(NO_LOCATIONS); | ||||
7765 | |||||
7766 | if (auto *CB = dyn_cast<CallBase>(&I)) { | ||||
7767 | |||||
7768 | // First check if we assume any memory is access is visible. | ||||
7769 | const auto &CBMemLocationAA = A.getAAFor<AAMemoryLocation>( | ||||
7770 | *this, IRPosition::callsite_function(*CB), DepClassTy::OPTIONAL); | ||||
7771 | LLVM_DEBUG(dbgs() << "[AAMemoryLocation] Categorize call site: " << Ido { } while (false) | ||||
7772 | << " [" << CBMemLocationAA << "]\n")do { } while (false); | ||||
7773 | |||||
7774 | if (CBMemLocationAA.isAssumedReadNone()) | ||||
7775 | return NO_LOCATIONS; | ||||
7776 | |||||
7777 | if (CBMemLocationAA.isAssumedInaccessibleMemOnly()) { | ||||
7778 | updateStateAndAccessesMap(AccessedLocs, NO_INACCESSIBLE_MEM, &I, nullptr, | ||||
7779 | Changed, getAccessKindFromInst(&I)); | ||||
7780 | return AccessedLocs.getAssumed(); | ||||
7781 | } | ||||
7782 | |||||
7783 | uint32_t CBAssumedNotAccessedLocs = | ||||
7784 | CBMemLocationAA.getAssumedNotAccessedLocation(); | ||||
7785 | |||||
7786 | // Set the argmemonly and global bit as we handle them separately below. | ||||
7787 | uint32_t CBAssumedNotAccessedLocsNoArgMem = | ||||
7788 | CBAssumedNotAccessedLocs | NO_ARGUMENT_MEM | NO_GLOBAL_MEM; | ||||
7789 | |||||
7790 | for (MemoryLocationsKind CurMLK = 1; CurMLK < NO_LOCATIONS; CurMLK *= 2) { | ||||
7791 | if (CBAssumedNotAccessedLocsNoArgMem & CurMLK) | ||||
7792 | continue; | ||||
7793 | updateStateAndAccessesMap(AccessedLocs, CurMLK, &I, nullptr, Changed, | ||||
7794 | getAccessKindFromInst(&I)); | ||||
7795 | } | ||||
7796 | |||||
7797 | // Now handle global memory if it might be accessed. This is slightly tricky | ||||
7798 | // as NO_GLOBAL_MEM has multiple bits set. | ||||
7799 | bool HasGlobalAccesses = ((~CBAssumedNotAccessedLocs) & NO_GLOBAL_MEM); | ||||
7800 | if (HasGlobalAccesses) { | ||||
7801 | auto AccessPred = [&](const Instruction *, const Value *Ptr, | ||||
7802 | AccessKind Kind, MemoryLocationsKind MLK) { | ||||
7803 | updateStateAndAccessesMap(AccessedLocs, MLK, &I, Ptr, Changed, | ||||
7804 | getAccessKindFromInst(&I)); | ||||
7805 | return true; | ||||
7806 | }; | ||||
7807 | if (!CBMemLocationAA.checkForAllAccessesToMemoryKind( | ||||
7808 | AccessPred, inverseLocation(NO_GLOBAL_MEM, false, false))) | ||||
7809 | return AccessedLocs.getWorstState(); | ||||
7810 | } | ||||
7811 | |||||
7812 | LLVM_DEBUG(do { } while (false) | ||||
7813 | dbgs() << "[AAMemoryLocation] Accessed state before argument handling: "do { } while (false) | ||||
7814 | << getMemoryLocationsAsStr(AccessedLocs.getAssumed()) << "\n")do { } while (false); | ||||
7815 | |||||
7816 | // Now handle argument memory if it might be accessed. | ||||
7817 | bool HasArgAccesses = ((~CBAssumedNotAccessedLocs) & NO_ARGUMENT_MEM); | ||||
7818 | if (HasArgAccesses) | ||||
7819 | categorizeArgumentPointerLocations(A, *CB, AccessedLocs, Changed); | ||||
7820 | |||||
7821 | LLVM_DEBUG(do { } while (false) | ||||
7822 | dbgs() << "[AAMemoryLocation] Accessed state after argument handling: "do { } while (false) | ||||
7823 | << getMemoryLocationsAsStr(AccessedLocs.getAssumed()) << "\n")do { } while (false); | ||||
7824 | |||||
7825 | return AccessedLocs.getAssumed(); | ||||
7826 | } | ||||
7827 | |||||
7828 | if (const Value *Ptr = getPointerOperand(&I, /* AllowVolatile */ true)) { | ||||
7829 | LLVM_DEBUG(do { } while (false) | ||||
7830 | dbgs() << "[AAMemoryLocation] Categorize memory access with pointer: "do { } while (false) | ||||
7831 | << I << " [" << *Ptr << "]\n")do { } while (false); | ||||
7832 | categorizePtrValue(A, I, *Ptr, AccessedLocs, Changed); | ||||
7833 | return AccessedLocs.getAssumed(); | ||||
7834 | } | ||||
7835 | |||||
7836 | LLVM_DEBUG(dbgs() << "[AAMemoryLocation] Failed to categorize instruction: "do { } while (false) | ||||
7837 | << I << "\n")do { } while (false); | ||||
7838 | updateStateAndAccessesMap(AccessedLocs, NO_UNKOWN_MEM, &I, nullptr, Changed, | ||||
7839 | getAccessKindFromInst(&I)); | ||||
7840 | return AccessedLocs.getAssumed(); | ||||
7841 | } | ||||
7842 | |||||
7843 | /// An AA to represent the memory behavior function attributes. | ||||
7844 | struct AAMemoryLocationFunction final : public AAMemoryLocationImpl { | ||||
7845 | AAMemoryLocationFunction(const IRPosition &IRP, Attributor &A) | ||||
7846 | : AAMemoryLocationImpl(IRP, A) {} | ||||
7847 | |||||
7848 | /// See AbstractAttribute::updateImpl(Attributor &A). | ||||
7849 | virtual ChangeStatus updateImpl(Attributor &A) override { | ||||
7850 | |||||
7851 | const auto &MemBehaviorAA = | ||||
7852 | A.getAAFor<AAMemoryBehavior>(*this, getIRPosition(), DepClassTy::NONE); | ||||
7853 | if (MemBehaviorAA.isAssumedReadNone()) { | ||||
7854 | if (MemBehaviorAA.isKnownReadNone()) | ||||
7855 | return indicateOptimisticFixpoint(); | ||||
7856 | assert(isAssumedReadNone() &&(static_cast<void> (0)) | ||||
7857 | "AAMemoryLocation was not read-none but AAMemoryBehavior was!")(static_cast<void> (0)); | ||||
7858 | A.recordDependence(MemBehaviorAA, *this, DepClassTy::OPTIONAL); | ||||
7859 | return ChangeStatus::UNCHANGED; | ||||
7860 | } | ||||
7861 | |||||
7862 | // The current assumed state used to determine a change. | ||||
7863 | auto AssumedState = getAssumed(); | ||||
7864 | bool Changed = false; | ||||
7865 | |||||
7866 | auto CheckRWInst = [&](Instruction &I) { | ||||
7867 | MemoryLocationsKind MLK = categorizeAccessedLocations(A, I, Changed); | ||||
7868 | LLVM_DEBUG(dbgs() << "[AAMemoryLocation] Accessed locations for " << Ido { } while (false) | ||||
7869 | << ": " << getMemoryLocationsAsStr(MLK) << "\n")do { } while (false); | ||||
7870 | removeAssumedBits(inverseLocation(MLK, false, false)); | ||||
7871 | // Stop once only the valid bit set in the *not assumed location*, thus | ||||
7872 | // once we don't actually exclude any memory locations in the state. | ||||
7873 | return getAssumedNotAccessedLocation() != VALID_STATE; | ||||
7874 | }; | ||||
7875 | |||||
7876 | bool UsedAssumedInformation = false; | ||||
7877 | if (!A.checkForAllReadWriteInstructions(CheckRWInst, *this, | ||||
7878 | UsedAssumedInformation)) | ||||
7879 | return indicatePessimisticFixpoint(); | ||||
7880 | |||||
7881 | Changed |= AssumedState != getAssumed(); | ||||
7882 | return Changed ? ChangeStatus::CHANGED : ChangeStatus::UNCHANGED; | ||||
7883 | } | ||||
7884 | |||||
7885 | /// See AbstractAttribute::trackStatistics() | ||||
7886 | void trackStatistics() const override { | ||||
7887 | if (isAssumedReadNone()) | ||||
7888 | STATS_DECLTRACK_FN_ATTR(readnone){ static llvm::Statistic NumIRFunction_readnone = {"attributor" , "NumIRFunction_readnone", ("Number of " "functions" " marked '" "readnone" "'")};; ++(NumIRFunction_readnone); } | ||||
7889 | else if (isAssumedArgMemOnly()) | ||||
7890 | STATS_DECLTRACK_FN_ATTR(argmemonly){ static llvm::Statistic NumIRFunction_argmemonly = {"attributor" , "NumIRFunction_argmemonly", ("Number of " "functions" " marked '" "argmemonly" "'")};; ++(NumIRFunction_argmemonly); } | ||||
7891 | else if (isAssumedInaccessibleMemOnly()) | ||||
7892 | STATS_DECLTRACK_FN_ATTR(inaccessiblememonly){ static llvm::Statistic NumIRFunction_inaccessiblememonly = { "attributor", "NumIRFunction_inaccessiblememonly", ("Number of " "functions" " marked '" "inaccessiblememonly" "'")};; ++(NumIRFunction_inaccessiblememonly ); } | ||||
7893 | else if (isAssumedInaccessibleOrArgMemOnly()) | ||||
7894 | STATS_DECLTRACK_FN_ATTR(inaccessiblememorargmemonly){ static llvm::Statistic NumIRFunction_inaccessiblememorargmemonly = {"attributor", "NumIRFunction_inaccessiblememorargmemonly" , ("Number of " "functions" " marked '" "inaccessiblememorargmemonly" "'")};; ++(NumIRFunction_inaccessiblememorargmemonly); } | ||||
7895 | } | ||||
7896 | }; | ||||
7897 | |||||
7898 | /// AAMemoryLocation attribute for call sites. | ||||
7899 | struct AAMemoryLocationCallSite final : AAMemoryLocationImpl { | ||||
7900 | AAMemoryLocationCallSite(const IRPosition &IRP, Attributor &A) | ||||
7901 | : AAMemoryLocationImpl(IRP, A) {} | ||||
7902 | |||||
7903 | /// See AbstractAttribute::initialize(...). | ||||
7904 | void initialize(Attributor &A) override { | ||||
7905 | AAMemoryLocationImpl::initialize(A); | ||||
7906 | Function *F = getAssociatedFunction(); | ||||
7907 | if (!F || F->isDeclaration()) | ||||
7908 | indicatePessimisticFixpoint(); | ||||
7909 | } | ||||
7910 | |||||
7911 | /// See AbstractAttribute::updateImpl(...). | ||||
7912 | ChangeStatus updateImpl(Attributor &A) override { | ||||
7913 | // TODO: Once we have call site specific value information we can provide | ||||
7914 | // call site specific liveness liveness information and then it makes | ||||
7915 | // sense to specialize attributes for call sites arguments instead of | ||||
7916 | // redirecting requests to the callee argument. | ||||
7917 | Function *F = getAssociatedFunction(); | ||||
7918 | const IRPosition &FnPos = IRPosition::function(*F); | ||||
7919 | auto &FnAA = | ||||
7920 | A.getAAFor<AAMemoryLocation>(*this, FnPos, DepClassTy::REQUIRED); | ||||
7921 | bool Changed = false; | ||||
7922 | auto AccessPred = [&](const Instruction *I, const Value *Ptr, | ||||
7923 | AccessKind Kind, MemoryLocationsKind MLK) { | ||||
7924 | updateStateAndAccessesMap(getState(), MLK, I, Ptr, Changed, | ||||
7925 | getAccessKindFromInst(I)); | ||||
7926 | return true; | ||||
7927 | }; | ||||
7928 | if (!FnAA.checkForAllAccessesToMemoryKind(AccessPred, ALL_LOCATIONS)) | ||||
7929 | return indicatePessimisticFixpoint(); | ||||
7930 | return Changed ? ChangeStatus::CHANGED : ChangeStatus::UNCHANGED; | ||||
7931 | } | ||||
7932 | |||||
7933 | /// See AbstractAttribute::trackStatistics() | ||||
7934 | void trackStatistics() const override { | ||||
7935 | if (isAssumedReadNone()) | ||||
7936 | STATS_DECLTRACK_CS_ATTR(readnone){ static llvm::Statistic NumIRCS_readnone = {"attributor", "NumIRCS_readnone" , ("Number of " "call site" " marked '" "readnone" "'")};; ++ (NumIRCS_readnone); } | ||||
7937 | } | ||||
7938 | }; | ||||
7939 | |||||
7940 | /// ------------------ Value Constant Range Attribute ------------------------- | ||||
7941 | |||||
7942 | struct AAValueConstantRangeImpl : AAValueConstantRange { | ||||
7943 | using StateType = IntegerRangeState; | ||||
7944 | AAValueConstantRangeImpl(const IRPosition &IRP, Attributor &A) | ||||
7945 | : AAValueConstantRange(IRP, A) {} | ||||
7946 | |||||
7947 | /// See AbstractAttribute::initialize(..). | ||||
7948 | void initialize(Attributor &A) override { | ||||
7949 | if (A.hasSimplificationCallback(getIRPosition())) { | ||||
7950 | indicatePessimisticFixpoint(); | ||||
7951 | return; | ||||
7952 | } | ||||
7953 | |||||
7954 | // Intersect a range given by SCEV. | ||||
7955 | intersectKnown(getConstantRangeFromSCEV(A, getCtxI())); | ||||
7956 | |||||
7957 | // Intersect a range given by LVI. | ||||
7958 | intersectKnown(getConstantRangeFromLVI(A, getCtxI())); | ||||
7959 | } | ||||
7960 | |||||
7961 | /// See AbstractAttribute::getAsStr(). | ||||
7962 | const std::string getAsStr() const override { | ||||
7963 | std::string Str; | ||||
7964 | llvm::raw_string_ostream OS(Str); | ||||
7965 | OS << "range(" << getBitWidth() << ")<"; | ||||
7966 | getKnown().print(OS); | ||||
7967 | OS << " / "; | ||||
7968 | getAssumed().print(OS); | ||||
7969 | OS << ">"; | ||||
7970 | return OS.str(); | ||||
7971 | } | ||||
7972 | |||||
7973 | /// Helper function to get a SCEV expr for the associated value at program | ||||
7974 | /// point \p I. | ||||
7975 | const SCEV *getSCEV(Attributor &A, const Instruction *I = nullptr) const { | ||||
7976 | if (!getAnchorScope()) | ||||
7977 | return nullptr; | ||||
7978 | |||||
7979 | ScalarEvolution *SE = | ||||
7980 | A.getInfoCache().getAnalysisResultForFunction<ScalarEvolutionAnalysis>( | ||||
7981 | *getAnchorScope()); | ||||
7982 | |||||
7983 | LoopInfo *LI = A.getInfoCache().getAnalysisResultForFunction<LoopAnalysis>( | ||||
7984 | *getAnchorScope()); | ||||
7985 | |||||
7986 | if (!SE || !LI) | ||||
7987 | return nullptr; | ||||
7988 | |||||
7989 | const SCEV *S = SE->getSCEV(&getAssociatedValue()); | ||||
7990 | if (!I) | ||||
7991 | return S; | ||||
7992 | |||||
7993 | return SE->getSCEVAtScope(S, LI->getLoopFor(I->getParent())); | ||||
7994 | } | ||||
7995 | |||||
7996 | /// Helper function to get a range from SCEV for the associated value at | ||||
7997 | /// program point \p I. | ||||
7998 | ConstantRange getConstantRangeFromSCEV(Attributor &A, | ||||
7999 | const Instruction *I = nullptr) const { | ||||
8000 | if (!getAnchorScope()) | ||||
8001 | return getWorstState(getBitWidth()); | ||||
8002 | |||||
8003 | ScalarEvolution *SE = | ||||
8004 | A.getInfoCache().getAnalysisResultForFunction<ScalarEvolutionAnalysis>( | ||||
8005 | *getAnchorScope()); | ||||
8006 | |||||
8007 | const SCEV *S = getSCEV(A, I); | ||||
8008 | if (!SE || !S) | ||||
8009 | return getWorstState(getBitWidth()); | ||||
8010 | |||||
8011 | return SE->getUnsignedRange(S); | ||||
8012 | } | ||||
8013 | |||||
8014 | /// Helper function to get a range from LVI for the associated value at | ||||
8015 | /// program point \p I. | ||||
8016 | ConstantRange | ||||
8017 | getConstantRangeFromLVI(Attributor &A, | ||||
8018 | const Instruction *CtxI = nullptr) const { | ||||
8019 | if (!getAnchorScope()) | ||||
8020 | return getWorstState(getBitWidth()); | ||||
8021 | |||||
8022 | LazyValueInfo *LVI = | ||||
8023 | A.getInfoCache().getAnalysisResultForFunction<LazyValueAnalysis>( | ||||
8024 | *getAnchorScope()); | ||||
8025 | |||||
8026 | if (!LVI || !CtxI) | ||||
8027 | return getWorstState(getBitWidth()); | ||||
8028 | return LVI->getConstantRange(&getAssociatedValue(), | ||||
8029 | const_cast<Instruction *>(CtxI)); | ||||
8030 | } | ||||
8031 | |||||
8032 | /// Return true if \p CtxI is valid for querying outside analyses. | ||||
8033 | /// This basically makes sure we do not ask intra-procedural analysis | ||||
8034 | /// about a context in the wrong function or a context that violates | ||||
8035 | /// dominance assumptions they might have. The \p AllowAACtxI flag indicates | ||||
8036 | /// if the original context of this AA is OK or should be considered invalid. | ||||
8037 | bool isValidCtxInstructionForOutsideAnalysis(Attributor &A, | ||||
8038 | const Instruction *CtxI, | ||||
8039 | bool AllowAACtxI) const { | ||||
8040 | if (!CtxI || (!AllowAACtxI && CtxI == getCtxI())) | ||||
8041 | return false; | ||||
8042 | |||||
8043 | // Our context might be in a different function, neither intra-procedural | ||||
8044 | // analysis (ScalarEvolution nor LazyValueInfo) can handle that. | ||||
8045 | if (!AA::isValidInScope(getAssociatedValue(), CtxI->getFunction())) | ||||
8046 | return false; | ||||
8047 | |||||
8048 | // If the context is not dominated by the value there are paths to the | ||||
8049 | // context that do not define the value. This cannot be handled by | ||||
8050 | // LazyValueInfo so we need to bail. | ||||
8051 | if (auto *I = dyn_cast<Instruction>(&getAssociatedValue())) { | ||||
8052 | InformationCache &InfoCache = A.getInfoCache(); | ||||
8053 | const DominatorTree *DT = | ||||
8054 | InfoCache.getAnalysisResultForFunction<DominatorTreeAnalysis>( | ||||
8055 | *I->getFunction()); | ||||
8056 | return DT && DT->dominates(I, CtxI); | ||||
8057 | } | ||||
8058 | |||||
8059 | return true; | ||||
8060 | } | ||||
8061 | |||||
8062 | /// See AAValueConstantRange::getKnownConstantRange(..). | ||||
8063 | ConstantRange | ||||
8064 | getKnownConstantRange(Attributor &A, | ||||
8065 | const Instruction *CtxI = nullptr) const override { | ||||
8066 | if (!isValidCtxInstructionForOutsideAnalysis(A, CtxI, | ||||
8067 | /* AllowAACtxI */ false)) | ||||
8068 | return getKnown(); | ||||
8069 | |||||
8070 | ConstantRange LVIR = getConstantRangeFromLVI(A, CtxI); | ||||
8071 | ConstantRange SCEVR = getConstantRangeFromSCEV(A, CtxI); | ||||
8072 | return getKnown().intersectWith(SCEVR).intersectWith(LVIR); | ||||
8073 | } | ||||
8074 | |||||
8075 | /// See AAValueConstantRange::getAssumedConstantRange(..). | ||||
8076 | ConstantRange | ||||
8077 | getAssumedConstantRange(Attributor &A, | ||||
8078 | const Instruction *CtxI = nullptr) const override { | ||||
8079 | // TODO: Make SCEV use Attributor assumption. | ||||
8080 | // We may be able to bound a variable range via assumptions in | ||||
8081 | // Attributor. ex.) If x is assumed to be in [1, 3] and y is known to | ||||
8082 | // evolve to x^2 + x, then we can say that y is in [2, 12]. | ||||
8083 | if (!isValidCtxInstructionForOutsideAnalysis(A, CtxI, | ||||
8084 | /* AllowAACtxI */ false)) | ||||
8085 | return getAssumed(); | ||||
8086 | |||||
8087 | ConstantRange LVIR = getConstantRangeFromLVI(A, CtxI); | ||||
8088 | ConstantRange SCEVR = getConstantRangeFromSCEV(A, CtxI); | ||||
8089 | return getAssumed().intersectWith(SCEVR).intersectWith(LVIR); | ||||
8090 | } | ||||
8091 | |||||
8092 | /// Helper function to create MDNode for range metadata. | ||||
8093 | static MDNode * | ||||
8094 | getMDNodeForConstantRange(Type *Ty, LLVMContext &Ctx, | ||||
8095 | const ConstantRange &AssumedConstantRange) { | ||||
8096 | Metadata *LowAndHigh[] = {ConstantAsMetadata::get(ConstantInt::get( | ||||
8097 | Ty, AssumedConstantRange.getLower())), | ||||
8098 | ConstantAsMetadata::get(ConstantInt::get( | ||||
8099 | Ty, AssumedConstantRange.getUpper()))}; | ||||
8100 | return MDNode::get(Ctx, LowAndHigh); | ||||
8101 | } | ||||
8102 | |||||
8103 | /// Return true if \p Assumed is included in \p KnownRanges. | ||||
8104 | static bool isBetterRange(const ConstantRange &Assumed, MDNode *KnownRanges) { | ||||
8105 | |||||
8106 | if (Assumed.isFullSet()) | ||||
8107 | return false; | ||||
8108 | |||||
8109 | if (!KnownRanges) | ||||
8110 | return true; | ||||
8111 | |||||
8112 | // If multiple ranges are annotated in IR, we give up to annotate assumed | ||||
8113 | // range for now. | ||||
8114 | |||||
8115 | // TODO: If there exists a known range which containts assumed range, we | ||||
8116 | // can say assumed range is better. | ||||
8117 | if (KnownRanges->getNumOperands() > 2) | ||||
8118 | return false; | ||||
8119 | |||||
8120 | ConstantInt *Lower = | ||||
8121 | mdconst::extract<ConstantInt>(KnownRanges->getOperand(0)); | ||||
8122 | ConstantInt *Upper = | ||||
8123 | mdconst::extract<ConstantInt>(KnownRanges->getOperand(1)); | ||||
8124 | |||||
8125 | ConstantRange Known(Lower->getValue(), Upper->getValue()); | ||||
8126 | return Known.contains(Assumed) && Known != Assumed; | ||||
8127 | } | ||||
8128 | |||||
8129 | /// Helper function to set range metadata. | ||||
8130 | static bool | ||||
8131 | setRangeMetadataIfisBetterRange(Instruction *I, | ||||
8132 | const ConstantRange &AssumedConstantRange) { | ||||
8133 | auto *OldRangeMD = I->getMetadata(LLVMContext::MD_range); | ||||
8134 | if (isBetterRange(AssumedConstantRange, OldRangeMD)) { | ||||
8135 | if (!AssumedConstantRange.isEmptySet()) { | ||||
8136 | I->setMetadata(LLVMContext::MD_range, | ||||
8137 | getMDNodeForConstantRange(I->getType(), I->getContext(), | ||||
8138 | AssumedConstantRange)); | ||||
8139 | return true; | ||||
8140 | } | ||||
8141 | } | ||||
8142 | return false; | ||||
8143 | } | ||||
8144 | |||||
8145 | /// See AbstractAttribute::manifest() | ||||
8146 | ChangeStatus manifest(Attributor &A) override { | ||||
8147 | ChangeStatus Changed = ChangeStatus::UNCHANGED; | ||||
8148 | ConstantRange AssumedConstantRange = getAssumedConstantRange(A); | ||||
8149 | assert(!AssumedConstantRange.isFullSet() && "Invalid state")(static_cast<void> (0)); | ||||
8150 | |||||
8151 | auto &V = getAssociatedValue(); | ||||
8152 | if (!AssumedConstantRange.isEmptySet() && | ||||
8153 | !AssumedConstantRange.isSingleElement()) { | ||||
8154 | if (Instruction *I = dyn_cast<Instruction>(&V)) { | ||||
8155 | assert(I == getCtxI() && "Should not annotate an instruction which is "(static_cast<void> (0)) | ||||
8156 | "not the context instruction")(static_cast<void> (0)); | ||||
8157 | if (isa<CallInst>(I) || isa<LoadInst>(I)) | ||||
8158 | if (setRangeMetadataIfisBetterRange(I, AssumedConstantRange)) | ||||
8159 | Changed = ChangeStatus::CHANGED; | ||||
8160 | } | ||||
8161 | } | ||||
8162 | |||||
8163 | return Changed; | ||||
8164 | } | ||||
8165 | }; | ||||
8166 | |||||
8167 | struct AAValueConstantRangeArgument final | ||||
8168 | : AAArgumentFromCallSiteArguments< | ||||
8169 | AAValueConstantRange, AAValueConstantRangeImpl, IntegerRangeState, | ||||
8170 | true /* BridgeCallBaseContext */> { | ||||
8171 | using Base = AAArgumentFromCallSiteArguments< | ||||
8172 | AAValueConstantRange, AAValueConstantRangeImpl, IntegerRangeState, | ||||
8173 | true /* BridgeCallBaseContext */>; | ||||
8174 | AAValueConstantRangeArgument(const IRPosition &IRP, Attributor &A) | ||||
8175 | : Base(IRP, A) {} | ||||
8176 | |||||
8177 | /// See AbstractAttribute::initialize(..). | ||||
8178 | void initialize(Attributor &A) override { | ||||
8179 | if (!getAnchorScope() || getAnchorScope()->isDeclaration()) { | ||||
8180 | indicatePessimisticFixpoint(); | ||||
8181 | } else { | ||||
8182 | Base::initialize(A); | ||||
8183 | } | ||||
8184 | } | ||||
8185 | |||||
8186 | /// See AbstractAttribute::trackStatistics() | ||||
8187 | void trackStatistics() const override { | ||||
8188 | STATS_DECLTRACK_ARG_ATTR(value_range){ static llvm::Statistic NumIRArguments_value_range = {"attributor" , "NumIRArguments_value_range", ("Number of " "arguments" " marked '" "value_range" "'")};; ++(NumIRArguments_value_range); } | ||||
8189 | } | ||||
8190 | }; | ||||
8191 | |||||
8192 | struct AAValueConstantRangeReturned | ||||
8193 | : AAReturnedFromReturnedValues<AAValueConstantRange, | ||||
8194 | AAValueConstantRangeImpl, | ||||
8195 | AAValueConstantRangeImpl::StateType, | ||||
8196 | /* PropogateCallBaseContext */ true> { | ||||
8197 | using Base = | ||||
8198 | AAReturnedFromReturnedValues<AAValueConstantRange, | ||||
8199 | AAValueConstantRangeImpl, | ||||
8200 | AAValueConstantRangeImpl::StateType, | ||||
8201 | /* PropogateCallBaseContext */ true>; | ||||
8202 | AAValueConstantRangeReturned(const IRPosition &IRP, Attributor &A) | ||||
8203 | : Base(IRP, A) {} | ||||
8204 | |||||
8205 | /// See AbstractAttribute::initialize(...). | ||||
8206 | void initialize(Attributor &A) override {} | ||||
8207 | |||||
8208 | /// See AbstractAttribute::trackStatistics() | ||||
8209 | void trackStatistics() const override { | ||||
8210 | STATS_DECLTRACK_FNRET_ATTR(value_range){ static llvm::Statistic NumIRFunctionReturn_value_range = {"attributor" , "NumIRFunctionReturn_value_range", ("Number of " "function returns" " marked '" "value_range" "'")};; ++(NumIRFunctionReturn_value_range ); } | ||||
8211 | } | ||||
8212 | }; | ||||
8213 | |||||
8214 | struct AAValueConstantRangeFloating : AAValueConstantRangeImpl { | ||||
8215 | AAValueConstantRangeFloating(const IRPosition &IRP, Attributor &A) | ||||
8216 | : AAValueConstantRangeImpl(IRP, A) {} | ||||
8217 | |||||
8218 | /// See AbstractAttribute::initialize(...). | ||||
8219 | void initialize(Attributor &A) override { | ||||
8220 | AAValueConstantRangeImpl::initialize(A); | ||||
8221 | if (isAtFixpoint()) | ||||
8222 | return; | ||||
8223 | |||||
8224 | Value &V = getAssociatedValue(); | ||||
8225 | |||||
8226 | if (auto *C = dyn_cast<ConstantInt>(&V)) { | ||||
8227 | unionAssumed(ConstantRange(C->getValue())); | ||||
8228 | indicateOptimisticFixpoint(); | ||||
8229 | return; | ||||
8230 | } | ||||
8231 | |||||
8232 | if (isa<UndefValue>(&V)) { | ||||
8233 | // Collapse the undef state to 0. | ||||
8234 | unionAssumed(ConstantRange(APInt(getBitWidth(), 0))); | ||||
8235 | indicateOptimisticFixpoint(); | ||||
8236 | return; | ||||
8237 | } | ||||
8238 | |||||
8239 | if (isa<CallBase>(&V)) | ||||
8240 | return; | ||||
8241 | |||||
8242 | if (isa<BinaryOperator>(&V) || isa<CmpInst>(&V) || isa<CastInst>(&V)) | ||||
8243 | return; | ||||
8244 | |||||
8245 | // If it is a load instruction with range metadata, use it. | ||||
8246 | if (LoadInst *LI = dyn_cast<LoadInst>(&V)) | ||||
8247 | if (auto *RangeMD = LI->getMetadata(LLVMContext::MD_range)) { | ||||
8248 | intersectKnown(getConstantRangeFromMetadata(*RangeMD)); | ||||
8249 | return; | ||||
8250 | } | ||||
8251 | |||||
8252 | // We can work with PHI and select instruction as we traverse their operands | ||||
8253 | // during update. | ||||
8254 | if (isa<SelectInst>(V) || isa<PHINode>(V)) | ||||
8255 | return; | ||||
8256 | |||||
8257 | // Otherwise we give up. | ||||
8258 | indicatePessimisticFixpoint(); | ||||
8259 | |||||
8260 | LLVM_DEBUG(dbgs() << "[AAValueConstantRange] We give up: "do { } while (false) | ||||
8261 | << getAssociatedValue() << "\n")do { } while (false); | ||||
8262 | } | ||||
8263 | |||||
8264 | bool calculateBinaryOperator( | ||||
8265 | Attributor &A, BinaryOperator *BinOp, IntegerRangeState &T, | ||||
8266 | const Instruction *CtxI, | ||||
8267 | SmallVectorImpl<const AAValueConstantRange *> &QuerriedAAs) { | ||||
8268 | Value *LHS = BinOp->getOperand(0); | ||||
8269 | Value *RHS = BinOp->getOperand(1); | ||||
8270 | |||||
8271 | // Simplify the operands first. | ||||
8272 | bool UsedAssumedInformation = false; | ||||
8273 | const auto &SimplifiedLHS = | ||||
8274 | A.getAssumedSimplified(IRPosition::value(*LHS, getCallBaseContext()), | ||||
8275 | *this, UsedAssumedInformation); | ||||
8276 | if (!SimplifiedLHS.hasValue()) | ||||
8277 | return true; | ||||
8278 | if (!SimplifiedLHS.getValue()) | ||||
8279 | return false; | ||||
8280 | LHS = *SimplifiedLHS; | ||||
8281 | |||||
8282 | const auto &SimplifiedRHS = | ||||
8283 | A.getAssumedSimplified(IRPosition::value(*RHS, getCallBaseContext()), | ||||
8284 | *this, UsedAssumedInformation); | ||||
8285 | if (!SimplifiedRHS.hasValue()) | ||||
8286 | return true; | ||||
8287 | if (!SimplifiedRHS.getValue()) | ||||
8288 | return false; | ||||
8289 | RHS = *SimplifiedRHS; | ||||
8290 | |||||
8291 | // TODO: Allow non integers as well. | ||||
8292 | if (!LHS->getType()->isIntegerTy() || !RHS->getType()->isIntegerTy()) | ||||
8293 | return false; | ||||
8294 | |||||
8295 | auto &LHSAA = A.getAAFor<AAValueConstantRange>( | ||||
8296 | *this, IRPosition::value(*LHS, getCallBaseContext()), | ||||
8297 | DepClassTy::REQUIRED); | ||||
8298 | QuerriedAAs.push_back(&LHSAA); | ||||
8299 | auto LHSAARange = LHSAA.getAssumedConstantRange(A, CtxI); | ||||
8300 | |||||
8301 | auto &RHSAA = A.getAAFor<AAValueConstantRange>( | ||||
8302 | *this, IRPosition::value(*RHS, getCallBaseContext()), | ||||
8303 | DepClassTy::REQUIRED); | ||||
8304 | QuerriedAAs.push_back(&RHSAA); | ||||
8305 | auto RHSAARange = RHSAA.getAssumedConstantRange(A, CtxI); | ||||
8306 | |||||
8307 | auto AssumedRange = LHSAARange.binaryOp(BinOp->getOpcode(), RHSAARange); | ||||
8308 | |||||
8309 | T.unionAssumed(AssumedRange); | ||||
8310 | |||||
8311 | // TODO: Track a known state too. | ||||
8312 | |||||
8313 | return T.isValidState(); | ||||
8314 | } | ||||
8315 | |||||
8316 | bool calculateCastInst( | ||||
8317 | Attributor &A, CastInst *CastI, IntegerRangeState &T, | ||||
8318 | const Instruction *CtxI, | ||||
8319 | SmallVectorImpl<const AAValueConstantRange *> &QuerriedAAs) { | ||||
8320 | assert(CastI->getNumOperands() == 1 && "Expected cast to be unary!")(static_cast<void> (0)); | ||||
8321 | // TODO: Allow non integers as well. | ||||
8322 | Value *OpV = CastI->getOperand(0); | ||||
8323 | |||||
8324 | // Simplify the operand first. | ||||
8325 | bool UsedAssumedInformation = false; | ||||
8326 | const auto &SimplifiedOpV = | ||||
8327 | A.getAssumedSimplified(IRPosition::value(*OpV, getCallBaseContext()), | ||||
8328 | *this, UsedAssumedInformation); | ||||
8329 | if (!SimplifiedOpV.hasValue()) | ||||
8330 | return true; | ||||
8331 | if (!SimplifiedOpV.getValue()) | ||||
8332 | return false; | ||||
8333 | OpV = *SimplifiedOpV; | ||||
8334 | |||||
8335 | if (!OpV->getType()->isIntegerTy()) | ||||
8336 | return false; | ||||
8337 | |||||
8338 | auto &OpAA = A.getAAFor<AAValueConstantRange>( | ||||
8339 | *this, IRPosition::value(*OpV, getCallBaseContext()), | ||||
8340 | DepClassTy::REQUIRED); | ||||
8341 | QuerriedAAs.push_back(&OpAA); | ||||
8342 | T.unionAssumed( | ||||
8343 | OpAA.getAssumed().castOp(CastI->getOpcode(), getState().getBitWidth())); | ||||
8344 | return T.isValidState(); | ||||
8345 | } | ||||
8346 | |||||
8347 | bool | ||||
8348 | calculateCmpInst(Attributor &A, CmpInst *CmpI, IntegerRangeState &T, | ||||
8349 | const Instruction *CtxI, | ||||
8350 | SmallVectorImpl<const AAValueConstantRange *> &QuerriedAAs) { | ||||
8351 | Value *LHS = CmpI->getOperand(0); | ||||
8352 | Value *RHS = CmpI->getOperand(1); | ||||
8353 | |||||
8354 | // Simplify the operands first. | ||||
8355 | bool UsedAssumedInformation = false; | ||||
8356 | const auto &SimplifiedLHS = | ||||
8357 | A.getAssumedSimplified(IRPosition::value(*LHS, getCallBaseContext()), | ||||
8358 | *this, UsedAssumedInformation); | ||||
8359 | if (!SimplifiedLHS.hasValue()) | ||||
8360 | return true; | ||||
8361 | if (!SimplifiedLHS.getValue()) | ||||
8362 | return false; | ||||
8363 | LHS = *SimplifiedLHS; | ||||
8364 | |||||
8365 | const auto &SimplifiedRHS = | ||||
8366 | A.getAssumedSimplified(IRPosition::value(*RHS, getCallBaseContext()), | ||||
8367 | *this, UsedAssumedInformation); | ||||
8368 | if (!SimplifiedRHS.hasValue()) | ||||
8369 | return true; | ||||
8370 | if (!SimplifiedRHS.getValue()) | ||||
8371 | return false; | ||||
8372 | RHS = *SimplifiedRHS; | ||||
8373 | |||||
8374 | // TODO: Allow non integers as well. | ||||
8375 | if (!LHS->getType()->isIntegerTy() || !RHS->getType()->isIntegerTy()) | ||||
8376 | return false; | ||||
8377 | |||||
8378 | auto &LHSAA = A.getAAFor<AAValueConstantRange>( | ||||
8379 | *this, IRPosition::value(*LHS, getCallBaseContext()), | ||||
8380 | DepClassTy::REQUIRED); | ||||
8381 | QuerriedAAs.push_back(&LHSAA); | ||||
8382 | auto &RHSAA = A.getAAFor<AAValueConstantRange>( | ||||
8383 | *this, IRPosition::value(*RHS, getCallBaseContext()), | ||||
8384 | DepClassTy::REQUIRED); | ||||
8385 | QuerriedAAs.push_back(&RHSAA); | ||||
8386 | auto LHSAARange = LHSAA.getAssumedConstantRange(A, CtxI); | ||||
8387 | auto RHSAARange = RHSAA.getAssumedConstantRange(A, CtxI); | ||||
8388 | |||||
8389 | // If one of them is empty set, we can't decide. | ||||
8390 | if (LHSAARange.isEmptySet() || RHSAARange.isEmptySet()) | ||||
8391 | return true; | ||||
8392 | |||||
8393 | bool MustTrue = false, MustFalse = false; | ||||
8394 | |||||
8395 | auto AllowedRegion = | ||||
8396 | ConstantRange::makeAllowedICmpRegion(CmpI->getPredicate(), RHSAARange); | ||||
8397 | |||||
8398 | if (AllowedRegion.intersectWith(LHSAARange).isEmptySet()) | ||||
8399 | MustFalse = true; | ||||
8400 | |||||
8401 | if (LHSAARange.icmp(CmpI->getPredicate(), RHSAARange)) | ||||
8402 | MustTrue = true; | ||||
8403 | |||||
8404 | assert((!MustTrue || !MustFalse) &&(static_cast<void> (0)) | ||||
8405 | "Either MustTrue or MustFalse should be false!")(static_cast<void> (0)); | ||||
8406 | |||||
8407 | if (MustTrue) | ||||
8408 | T.unionAssumed(ConstantRange(APInt(/* numBits */ 1, /* val */ 1))); | ||||
8409 | else if (MustFalse) | ||||
8410 | T.unionAssumed(ConstantRange(APInt(/* numBits */ 1, /* val */ 0))); | ||||
8411 | else | ||||
8412 | T.unionAssumed(ConstantRange(/* BitWidth */ 1, /* isFullSet */ true)); | ||||
8413 | |||||
8414 | LLVM_DEBUG(dbgs() << "[AAValueConstantRange] " << *CmpI << " " << LHSAAdo { } while (false) | ||||
8415 | << " " << RHSAA << "\n")do { } while (false); | ||||
8416 | |||||
8417 | // TODO: Track a known state too. | ||||
8418 | return T.isValidState(); | ||||
8419 | } | ||||
8420 | |||||
8421 | /// See AbstractAttribute::updateImpl(...). | ||||
8422 | ChangeStatus updateImpl(Attributor &A) override { | ||||
8423 | auto VisitValueCB = [&](Value &V, const Instruction *CtxI, | ||||
8424 | IntegerRangeState &T, bool Stripped) -> bool { | ||||
8425 | Instruction *I = dyn_cast<Instruction>(&V); | ||||
8426 | if (!I || isa<CallBase>(I)) { | ||||
8427 | |||||
8428 | // Simplify the operand first. | ||||
8429 | bool UsedAssumedInformation = false; | ||||
8430 | const auto &SimplifiedOpV = | ||||
8431 | A.getAssumedSimplified(IRPosition::value(V, getCallBaseContext()), | ||||
8432 | *this, UsedAssumedInformation); | ||||
8433 | if (!SimplifiedOpV.hasValue()) | ||||
8434 | return true; | ||||
8435 | if (!SimplifiedOpV.getValue()) | ||||
8436 | return false; | ||||
8437 | Value *VPtr = *SimplifiedOpV; | ||||
8438 | |||||
8439 | // If the value is not instruction, we query AA to Attributor. | ||||
8440 | const auto &AA = A.getAAFor<AAValueConstantRange>( | ||||
8441 | *this, IRPosition::value(*VPtr, getCallBaseContext()), | ||||
8442 | DepClassTy::REQUIRED); | ||||
8443 | |||||
8444 | // Clamp operator is not used to utilize a program point CtxI. | ||||
8445 | T.unionAssumed(AA.getAssumedConstantRange(A, CtxI)); | ||||
8446 | |||||
8447 | return T.isValidState(); | ||||
8448 | } | ||||
8449 | |||||
8450 | SmallVector<const AAValueConstantRange *, 4> QuerriedAAs; | ||||
8451 | if (auto *BinOp = dyn_cast<BinaryOperator>(I)) { | ||||
8452 | if (!calculateBinaryOperator(A, BinOp, T, CtxI, QuerriedAAs)) | ||||
8453 | return false; | ||||
8454 | } else if (auto *CmpI = dyn_cast<CmpInst>(I)) { | ||||
8455 | if (!calculateCmpInst(A, CmpI, T, CtxI, QuerriedAAs)) | ||||
8456 | return false; | ||||
8457 | } else if (auto *CastI = dyn_cast<CastInst>(I)) { | ||||
8458 | if (!calculateCastInst(A, CastI, T, CtxI, QuerriedAAs)) | ||||
8459 | return false; | ||||
8460 | } else { | ||||
8461 | // Give up with other instructions. | ||||
8462 | // TODO: Add other instructions | ||||
8463 | |||||
8464 | T.indicatePessimisticFixpoint(); | ||||
8465 | return false; | ||||
8466 | } | ||||
8467 | |||||
8468 | // Catch circular reasoning in a pessimistic way for now. | ||||
8469 | // TODO: Check how the range evolves and if we stripped anything, see also | ||||
8470 | // AADereferenceable or AAAlign for similar situations. | ||||
8471 | for (const AAValueConstantRange *QueriedAA : QuerriedAAs) { | ||||
8472 | if (QueriedAA != this) | ||||
8473 | continue; | ||||
8474 | // If we are in a stady state we do not need to worry. | ||||
8475 | if (T.getAssumed() == getState().getAssumed()) | ||||
8476 | continue; | ||||
8477 | T.indicatePessimisticFixpoint(); | ||||
8478 | } | ||||
8479 | |||||
8480 | return T.isValidState(); | ||||
8481 | }; | ||||
8482 | |||||
8483 | IntegerRangeState T(getBitWidth()); | ||||
8484 | |||||
8485 | if (!genericValueTraversal<IntegerRangeState>(A, getIRPosition(), *this, T, | ||||
8486 | VisitValueCB, getCtxI(), | ||||
8487 | /* UseValueSimplify */ false)) | ||||
8488 | return indicatePessimisticFixpoint(); | ||||
8489 | |||||
8490 | return clampStateAndIndicateChange(getState(), T); | ||||
8491 | } | ||||
8492 | |||||
8493 | /// See AbstractAttribute::trackStatistics() | ||||
8494 | void trackStatistics() const override { | ||||
8495 | STATS_DECLTRACK_FLOATING_ATTR(value_range){ static llvm::Statistic NumIRFloating_value_range = {"attributor" , "NumIRFloating_value_range", ("Number of floating values known to be '" "value_range" "'")};; ++(NumIRFloating_value_range); } | ||||
8496 | } | ||||
8497 | }; | ||||
8498 | |||||
8499 | struct AAValueConstantRangeFunction : AAValueConstantRangeImpl { | ||||
8500 | AAValueConstantRangeFunction(const IRPosition &IRP, Attributor &A) | ||||
8501 | : AAValueConstantRangeImpl(IRP, A) {} | ||||
8502 | |||||
8503 | /// See AbstractAttribute::initialize(...). | ||||
8504 | ChangeStatus updateImpl(Attributor &A) override { | ||||
8505 | llvm_unreachable("AAValueConstantRange(Function|CallSite)::updateImpl will "__builtin_unreachable() | ||||
8506 | "not be called")__builtin_unreachable(); | ||||
8507 | } | ||||
8508 | |||||
8509 | /// See AbstractAttribute::trackStatistics() | ||||
8510 | void trackStatistics() const override { STATS_DECLTRACK_FN_ATTR(value_range){ static llvm::Statistic NumIRFunction_value_range = {"attributor" , "NumIRFunction_value_range", ("Number of " "functions" " marked '" "value_range" "'")};; ++(NumIRFunction_value_range); } } | ||||
8511 | }; | ||||
8512 | |||||
8513 | struct AAValueConstantRangeCallSite : AAValueConstantRangeFunction { | ||||
8514 | AAValueConstantRangeCallSite(const IRPosition &IRP, Attributor &A) | ||||
8515 | : AAValueConstantRangeFunction(IRP, A) {} | ||||
8516 | |||||
8517 | /// See AbstractAttribute::trackStatistics() | ||||
8518 | void trackStatistics() const override { STATS_DECLTRACK_CS_ATTR(value_range){ static llvm::Statistic NumIRCS_value_range = {"attributor", "NumIRCS_value_range", ("Number of " "call site" " marked '" "value_range" "'")};; ++(NumIRCS_value_range); } } | ||||
8519 | }; | ||||
8520 | |||||
8521 | struct AAValueConstantRangeCallSiteReturned | ||||
8522 | : AACallSiteReturnedFromReturned<AAValueConstantRange, | ||||
8523 | AAValueConstantRangeImpl, | ||||
8524 | AAValueConstantRangeImpl::StateType, | ||||
8525 | /* IntroduceCallBaseContext */ true> { | ||||
8526 | AAValueConstantRangeCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
8527 | : AACallSiteReturnedFromReturned<AAValueConstantRange, | ||||
8528 | AAValueConstantRangeImpl, | ||||
8529 | AAValueConstantRangeImpl::StateType, | ||||
8530 | /* IntroduceCallBaseContext */ true>(IRP, | ||||
8531 | A) { | ||||
8532 | } | ||||
8533 | |||||
8534 | /// See AbstractAttribute::initialize(...). | ||||
8535 | void initialize(Attributor &A) override { | ||||
8536 | // If it is a load instruction with range metadata, use the metadata. | ||||
8537 | if (CallInst *CI = dyn_cast<CallInst>(&getAssociatedValue())) | ||||
8538 | if (auto *RangeMD = CI->getMetadata(LLVMContext::MD_range)) | ||||
8539 | intersectKnown(getConstantRangeFromMetadata(*RangeMD)); | ||||
8540 | |||||
8541 | AAValueConstantRangeImpl::initialize(A); | ||||
8542 | } | ||||
8543 | |||||
8544 | /// See AbstractAttribute::trackStatistics() | ||||
8545 | void trackStatistics() const override { | ||||
8546 | STATS_DECLTRACK_CSRET_ATTR(value_range){ static llvm::Statistic NumIRCSReturn_value_range = {"attributor" , "NumIRCSReturn_value_range", ("Number of " "call site returns" " marked '" "value_range" "'")};; ++(NumIRCSReturn_value_range ); } | ||||
8547 | } | ||||
8548 | }; | ||||
8549 | struct AAValueConstantRangeCallSiteArgument : AAValueConstantRangeFloating { | ||||
8550 | AAValueConstantRangeCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
8551 | : AAValueConstantRangeFloating(IRP, A) {} | ||||
8552 | |||||
8553 | /// See AbstractAttribute::manifest() | ||||
8554 | ChangeStatus manifest(Attributor &A) override { | ||||
8555 | return ChangeStatus::UNCHANGED; | ||||
8556 | } | ||||
8557 | |||||
8558 | /// See AbstractAttribute::trackStatistics() | ||||
8559 | void trackStatistics() const override { | ||||
8560 | STATS_DECLTRACK_CSARG_ATTR(value_range){ static llvm::Statistic NumIRCSArguments_value_range = {"attributor" , "NumIRCSArguments_value_range", ("Number of " "call site arguments" " marked '" "value_range" "'")};; ++(NumIRCSArguments_value_range ); } | ||||
8561 | } | ||||
8562 | }; | ||||
8563 | |||||
8564 | /// ------------------ Potential Values Attribute ------------------------- | ||||
8565 | |||||
8566 | struct AAPotentialValuesImpl : AAPotentialValues { | ||||
8567 | using StateType = PotentialConstantIntValuesState; | ||||
8568 | |||||
8569 | AAPotentialValuesImpl(const IRPosition &IRP, Attributor &A) | ||||
8570 | : AAPotentialValues(IRP, A) {} | ||||
8571 | |||||
8572 | /// See AbstractAttribute::initialize(..). | ||||
8573 | void initialize(Attributor &A) override { | ||||
8574 | if (A.hasSimplificationCallback(getIRPosition())) | ||||
8575 | indicatePessimisticFixpoint(); | ||||
8576 | else | ||||
8577 | AAPotentialValues::initialize(A); | ||||
8578 | } | ||||
8579 | |||||
8580 | /// See AbstractAttribute::getAsStr(). | ||||
8581 | const std::string getAsStr() const override { | ||||
8582 | std::string Str; | ||||
8583 | llvm::raw_string_ostream OS(Str); | ||||
8584 | OS << getState(); | ||||
8585 | return OS.str(); | ||||
8586 | } | ||||
8587 | |||||
8588 | /// See AbstractAttribute::updateImpl(...). | ||||
8589 | ChangeStatus updateImpl(Attributor &A) override { | ||||
8590 | return indicatePessimisticFixpoint(); | ||||
8591 | } | ||||
8592 | }; | ||||
8593 | |||||
8594 | struct AAPotentialValuesArgument final | ||||
8595 | : AAArgumentFromCallSiteArguments<AAPotentialValues, AAPotentialValuesImpl, | ||||
8596 | PotentialConstantIntValuesState> { | ||||
8597 | using Base = | ||||
8598 | AAArgumentFromCallSiteArguments<AAPotentialValues, AAPotentialValuesImpl, | ||||
8599 | PotentialConstantIntValuesState>; | ||||
8600 | AAPotentialValuesArgument(const IRPosition &IRP, Attributor &A) | ||||
8601 | : Base(IRP, A) {} | ||||
8602 | |||||
8603 | /// See AbstractAttribute::initialize(..). | ||||
8604 | void initialize(Attributor &A) override { | ||||
8605 | if (!getAnchorScope() || getAnchorScope()->isDeclaration()) { | ||||
8606 | indicatePessimisticFixpoint(); | ||||
8607 | } else { | ||||
8608 | Base::initialize(A); | ||||
8609 | } | ||||
8610 | } | ||||
8611 | |||||
8612 | /// See AbstractAttribute::trackStatistics() | ||||
8613 | void trackStatistics() const override { | ||||
8614 | STATS_DECLTRACK_ARG_ATTR(potential_values){ static llvm::Statistic NumIRArguments_potential_values = {"attributor" , "NumIRArguments_potential_values", ("Number of " "arguments" " marked '" "potential_values" "'")};; ++(NumIRArguments_potential_values ); } | ||||
8615 | } | ||||
8616 | }; | ||||
8617 | |||||
8618 | struct AAPotentialValuesReturned | ||||
8619 | : AAReturnedFromReturnedValues<AAPotentialValues, AAPotentialValuesImpl> { | ||||
8620 | using Base = | ||||
8621 | AAReturnedFromReturnedValues<AAPotentialValues, AAPotentialValuesImpl>; | ||||
8622 | AAPotentialValuesReturned(const IRPosition &IRP, Attributor &A) | ||||
8623 | : Base(IRP, A) {} | ||||
8624 | |||||
8625 | /// See AbstractAttribute::trackStatistics() | ||||
8626 | void trackStatistics() const override { | ||||
8627 | STATS_DECLTRACK_FNRET_ATTR(potential_values){ static llvm::Statistic NumIRFunctionReturn_potential_values = {"attributor", "NumIRFunctionReturn_potential_values", ("Number of " "function returns" " marked '" "potential_values" "'")};; ++ (NumIRFunctionReturn_potential_values); } | ||||
8628 | } | ||||
8629 | }; | ||||
8630 | |||||
8631 | struct AAPotentialValuesFloating : AAPotentialValuesImpl { | ||||
8632 | AAPotentialValuesFloating(const IRPosition &IRP, Attributor &A) | ||||
8633 | : AAPotentialValuesImpl(IRP, A) {} | ||||
8634 | |||||
8635 | /// See AbstractAttribute::initialize(..). | ||||
8636 | void initialize(Attributor &A) override { | ||||
8637 | AAPotentialValuesImpl::initialize(A); | ||||
8638 | if (isAtFixpoint()) | ||||
8639 | return; | ||||
8640 | |||||
8641 | Value &V = getAssociatedValue(); | ||||
8642 | |||||
8643 | if (auto *C = dyn_cast<ConstantInt>(&V)) { | ||||
8644 | unionAssumed(C->getValue()); | ||||
8645 | indicateOptimisticFixpoint(); | ||||
8646 | return; | ||||
8647 | } | ||||
8648 | |||||
8649 | if (isa<UndefValue>(&V)) { | ||||
8650 | unionAssumedWithUndef(); | ||||
8651 | indicateOptimisticFixpoint(); | ||||
8652 | return; | ||||
8653 | } | ||||
8654 | |||||
8655 | if (isa<BinaryOperator>(&V) || isa<ICmpInst>(&V) || isa<CastInst>(&V)) | ||||
8656 | return; | ||||
8657 | |||||
8658 | if (isa<SelectInst>(V) || isa<PHINode>(V) || isa<LoadInst>(V)) | ||||
8659 | return; | ||||
8660 | |||||
8661 | indicatePessimisticFixpoint(); | ||||
8662 | |||||
8663 | LLVM_DEBUG(dbgs() << "[AAPotentialValues] We give up: "do { } while (false) | ||||
8664 | << getAssociatedValue() << "\n")do { } while (false); | ||||
8665 | } | ||||
8666 | |||||
8667 | static bool calculateICmpInst(const ICmpInst *ICI, const APInt &LHS, | ||||
8668 | const APInt &RHS) { | ||||
8669 | ICmpInst::Predicate Pred = ICI->getPredicate(); | ||||
8670 | switch (Pred) { | ||||
8671 | case ICmpInst::ICMP_UGT: | ||||
8672 | return LHS.ugt(RHS); | ||||
8673 | case ICmpInst::ICMP_SGT: | ||||
8674 | return LHS.sgt(RHS); | ||||
8675 | case ICmpInst::ICMP_EQ: | ||||
8676 | return LHS.eq(RHS); | ||||
8677 | case ICmpInst::ICMP_UGE: | ||||
8678 | return LHS.uge(RHS); | ||||
8679 | case ICmpInst::ICMP_SGE: | ||||
8680 | return LHS.sge(RHS); | ||||
8681 | case ICmpInst::ICMP_ULT: | ||||
8682 | return LHS.ult(RHS); | ||||
8683 | case ICmpInst::ICMP_SLT: | ||||
8684 | return LHS.slt(RHS); | ||||
8685 | case ICmpInst::ICMP_NE: | ||||
8686 | return LHS.ne(RHS); | ||||
8687 | case ICmpInst::ICMP_ULE: | ||||
8688 | return LHS.ule(RHS); | ||||
8689 | case ICmpInst::ICMP_SLE: | ||||
8690 | return LHS.sle(RHS); | ||||
8691 | default: | ||||
8692 | llvm_unreachable("Invalid ICmp predicate!")__builtin_unreachable(); | ||||
8693 | } | ||||
8694 | } | ||||
8695 | |||||
8696 | static APInt calculateCastInst(const CastInst *CI, const APInt &Src, | ||||
8697 | uint32_t ResultBitWidth) { | ||||
8698 | Instruction::CastOps CastOp = CI->getOpcode(); | ||||
8699 | switch (CastOp) { | ||||
8700 | default: | ||||
8701 | llvm_unreachable("unsupported or not integer cast")__builtin_unreachable(); | ||||
8702 | case Instruction::Trunc: | ||||
8703 | return Src.trunc(ResultBitWidth); | ||||
8704 | case Instruction::SExt: | ||||
8705 | return Src.sext(ResultBitWidth); | ||||
8706 | case Instruction::ZExt: | ||||
8707 | return Src.zext(ResultBitWidth); | ||||
8708 | case Instruction::BitCast: | ||||
8709 | return Src; | ||||
8710 | } | ||||
8711 | } | ||||
8712 | |||||
8713 | static APInt calculateBinaryOperator(const BinaryOperator *BinOp, | ||||
8714 | const APInt &LHS, const APInt &RHS, | ||||
8715 | bool &SkipOperation, bool &Unsupported) { | ||||
8716 | Instruction::BinaryOps BinOpcode = BinOp->getOpcode(); | ||||
8717 | // Unsupported is set to true when the binary operator is not supported. | ||||
8718 | // SkipOperation is set to true when UB occur with the given operand pair | ||||
8719 | // (LHS, RHS). | ||||
8720 | // TODO: we should look at nsw and nuw keywords to handle operations | ||||
8721 | // that create poison or undef value. | ||||
8722 | switch (BinOpcode) { | ||||
8723 | default: | ||||
8724 | Unsupported = true; | ||||
8725 | return LHS; | ||||
8726 | case Instruction::Add: | ||||
8727 | return LHS + RHS; | ||||
8728 | case Instruction::Sub: | ||||
8729 | return LHS - RHS; | ||||
8730 | case Instruction::Mul: | ||||
8731 | return LHS * RHS; | ||||
8732 | case Instruction::UDiv: | ||||
8733 | if (RHS.isNullValue()) { | ||||
8734 | SkipOperation = true; | ||||
8735 | return LHS; | ||||
8736 | } | ||||
8737 | return LHS.udiv(RHS); | ||||
8738 | case Instruction::SDiv: | ||||
8739 | if (RHS.isNullValue()) { | ||||
8740 | SkipOperation = true; | ||||
8741 | return LHS; | ||||
8742 | } | ||||
8743 | return LHS.sdiv(RHS); | ||||
8744 | case Instruction::URem: | ||||
8745 | if (RHS.isNullValue()) { | ||||
8746 | SkipOperation = true; | ||||
8747 | return LHS; | ||||
8748 | } | ||||
8749 | return LHS.urem(RHS); | ||||
8750 | case Instruction::SRem: | ||||
8751 | if (RHS.isNullValue()) { | ||||
8752 | SkipOperation = true; | ||||
8753 | return LHS; | ||||
8754 | } | ||||
8755 | return LHS.srem(RHS); | ||||
8756 | case Instruction::Shl: | ||||
8757 | return LHS.shl(RHS); | ||||
8758 | case Instruction::LShr: | ||||
8759 | return LHS.lshr(RHS); | ||||
8760 | case Instruction::AShr: | ||||
8761 | return LHS.ashr(RHS); | ||||
8762 | case Instruction::And: | ||||
8763 | return LHS & RHS; | ||||
8764 | case Instruction::Or: | ||||
8765 | return LHS | RHS; | ||||
8766 | case Instruction::Xor: | ||||
8767 | return LHS ^ RHS; | ||||
8768 | } | ||||
8769 | } | ||||
8770 | |||||
8771 | bool calculateBinaryOperatorAndTakeUnion(const BinaryOperator *BinOp, | ||||
8772 | const APInt &LHS, const APInt &RHS) { | ||||
8773 | bool SkipOperation = false; | ||||
8774 | bool Unsupported = false; | ||||
8775 | APInt Result = | ||||
8776 | calculateBinaryOperator(BinOp, LHS, RHS, SkipOperation, Unsupported); | ||||
8777 | if (Unsupported) | ||||
8778 | return false; | ||||
8779 | // If SkipOperation is true, we can ignore this operand pair (L, R). | ||||
8780 | if (!SkipOperation) | ||||
8781 | unionAssumed(Result); | ||||
8782 | return isValidState(); | ||||
8783 | } | ||||
8784 | |||||
8785 | ChangeStatus updateWithICmpInst(Attributor &A, ICmpInst *ICI) { | ||||
8786 | auto AssumedBefore = getAssumed(); | ||||
8787 | Value *LHS = ICI->getOperand(0); | ||||
8788 | Value *RHS = ICI->getOperand(1); | ||||
8789 | |||||
8790 | // Simplify the operands first. | ||||
8791 | bool UsedAssumedInformation = false; | ||||
8792 | const auto &SimplifiedLHS = | ||||
8793 | A.getAssumedSimplified(IRPosition::value(*LHS, getCallBaseContext()), | ||||
8794 | *this, UsedAssumedInformation); | ||||
8795 | if (!SimplifiedLHS.hasValue()) | ||||
8796 | return ChangeStatus::UNCHANGED; | ||||
8797 | if (!SimplifiedLHS.getValue()) | ||||
8798 | return indicatePessimisticFixpoint(); | ||||
8799 | LHS = *SimplifiedLHS; | ||||
8800 | |||||
8801 | const auto &SimplifiedRHS = | ||||
8802 | A.getAssumedSimplified(IRPosition::value(*RHS, getCallBaseContext()), | ||||
8803 | *this, UsedAssumedInformation); | ||||
8804 | if (!SimplifiedRHS.hasValue()) | ||||
8805 | return ChangeStatus::UNCHANGED; | ||||
8806 | if (!SimplifiedRHS.getValue()) | ||||
8807 | return indicatePessimisticFixpoint(); | ||||
8808 | RHS = *SimplifiedRHS; | ||||
8809 | |||||
8810 | if (!LHS->getType()->isIntegerTy() || !RHS->getType()->isIntegerTy()) | ||||
8811 | return indicatePessimisticFixpoint(); | ||||
8812 | |||||
8813 | auto &LHSAA = A.getAAFor<AAPotentialValues>(*this, IRPosition::value(*LHS), | ||||
8814 | DepClassTy::REQUIRED); | ||||
8815 | if (!LHSAA.isValidState()) | ||||
8816 | return indicatePessimisticFixpoint(); | ||||
8817 | |||||
8818 | auto &RHSAA = A.getAAFor<AAPotentialValues>(*this, IRPosition::value(*RHS), | ||||
8819 | DepClassTy::REQUIRED); | ||||
8820 | if (!RHSAA.isValidState()) | ||||
8821 | return indicatePessimisticFixpoint(); | ||||
8822 | |||||
8823 | const DenseSet<APInt> &LHSAAPVS = LHSAA.getAssumedSet(); | ||||
8824 | const DenseSet<APInt> &RHSAAPVS = RHSAA.getAssumedSet(); | ||||
8825 | |||||
8826 | // TODO: make use of undef flag to limit potential values aggressively. | ||||
8827 | bool MaybeTrue = false, MaybeFalse = false; | ||||
8828 | const APInt Zero(RHS->getType()->getIntegerBitWidth(), 0); | ||||
8829 | if (LHSAA.undefIsContained() && RHSAA.undefIsContained()) { | ||||
8830 | // The result of any comparison between undefs can be soundly replaced | ||||
8831 | // with undef. | ||||
8832 | unionAssumedWithUndef(); | ||||
8833 | } else if (LHSAA.undefIsContained()) { | ||||
8834 | for (const APInt &R : RHSAAPVS) { | ||||
8835 | bool CmpResult = calculateICmpInst(ICI, Zero, R); | ||||
8836 | MaybeTrue |= CmpResult; | ||||
8837 | MaybeFalse |= !CmpResult; | ||||
8838 | if (MaybeTrue & MaybeFalse) | ||||
8839 | return indicatePessimisticFixpoint(); | ||||
8840 | } | ||||
8841 | } else if (RHSAA.undefIsContained()) { | ||||
8842 | for (const APInt &L : LHSAAPVS) { | ||||
8843 | bool CmpResult = calculateICmpInst(ICI, L, Zero); | ||||
8844 | MaybeTrue |= CmpResult; | ||||
8845 | MaybeFalse |= !CmpResult; | ||||
8846 | if (MaybeTrue & MaybeFalse) | ||||
8847 | return indicatePessimisticFixpoint(); | ||||
8848 | } | ||||
8849 | } else { | ||||
8850 | for (const APInt &L : LHSAAPVS) { | ||||
8851 | for (const APInt &R : RHSAAPVS) { | ||||
8852 | bool CmpResult = calculateICmpInst(ICI, L, R); | ||||
8853 | MaybeTrue |= CmpResult; | ||||
8854 | MaybeFalse |= !CmpResult; | ||||
8855 | if (MaybeTrue & MaybeFalse) | ||||
8856 | return indicatePessimisticFixpoint(); | ||||
8857 | } | ||||
8858 | } | ||||
8859 | } | ||||
8860 | if (MaybeTrue) | ||||
8861 | unionAssumed(APInt(/* numBits */ 1, /* val */ 1)); | ||||
8862 | if (MaybeFalse) | ||||
8863 | unionAssumed(APInt(/* numBits */ 1, /* val */ 0)); | ||||
8864 | return AssumedBefore == getAssumed() ? ChangeStatus::UNCHANGED | ||||
8865 | : ChangeStatus::CHANGED; | ||||
8866 | } | ||||
8867 | |||||
8868 | ChangeStatus updateWithSelectInst(Attributor &A, SelectInst *SI) { | ||||
8869 | auto AssumedBefore = getAssumed(); | ||||
8870 | Value *LHS = SI->getTrueValue(); | ||||
8871 | Value *RHS = SI->getFalseValue(); | ||||
8872 | |||||
8873 | // Simplify the operands first. | ||||
8874 | bool UsedAssumedInformation = false; | ||||
8875 | const auto &SimplifiedLHS = | ||||
8876 | A.getAssumedSimplified(IRPosition::value(*LHS, getCallBaseContext()), | ||||
8877 | *this, UsedAssumedInformation); | ||||
8878 | if (!SimplifiedLHS.hasValue()) | ||||
8879 | return ChangeStatus::UNCHANGED; | ||||
8880 | if (!SimplifiedLHS.getValue()) | ||||
8881 | return indicatePessimisticFixpoint(); | ||||
8882 | LHS = *SimplifiedLHS; | ||||
8883 | |||||
8884 | const auto &SimplifiedRHS = | ||||
8885 | A.getAssumedSimplified(IRPosition::value(*RHS, getCallBaseContext()), | ||||
8886 | *this, UsedAssumedInformation); | ||||
8887 | if (!SimplifiedRHS.hasValue()) | ||||
8888 | return ChangeStatus::UNCHANGED; | ||||
8889 | if (!SimplifiedRHS.getValue()) | ||||
8890 | return indicatePessimisticFixpoint(); | ||||
8891 | RHS = *SimplifiedRHS; | ||||
8892 | |||||
8893 | if (!LHS->getType()->isIntegerTy() || !RHS->getType()->isIntegerTy()) | ||||
8894 | return indicatePessimisticFixpoint(); | ||||
8895 | |||||
8896 | Optional<Constant *> C = A.getAssumedConstant(*SI->getCondition(), *this, | ||||
8897 | UsedAssumedInformation); | ||||
8898 | |||||
8899 | // Check if we only need one operand. | ||||
8900 | bool OnlyLeft = false, OnlyRight = false; | ||||
8901 | if (C.hasValue() && *C && (*C)->isOneValue()) | ||||
8902 | OnlyLeft = true; | ||||
8903 | else if (C.hasValue() && *C && (*C)->isZeroValue()) | ||||
8904 | OnlyRight = true; | ||||
8905 | |||||
8906 | const AAPotentialValues *LHSAA = nullptr, *RHSAA = nullptr; | ||||
8907 | if (!OnlyRight) { | ||||
8908 | LHSAA = &A.getAAFor<AAPotentialValues>(*this, IRPosition::value(*LHS), | ||||
8909 | DepClassTy::REQUIRED); | ||||
8910 | if (!LHSAA->isValidState()) | ||||
8911 | return indicatePessimisticFixpoint(); | ||||
8912 | } | ||||
8913 | if (!OnlyLeft) { | ||||
8914 | RHSAA = &A.getAAFor<AAPotentialValues>(*this, IRPosition::value(*RHS), | ||||
8915 | DepClassTy::REQUIRED); | ||||
8916 | if (!RHSAA->isValidState()) | ||||
8917 | return indicatePessimisticFixpoint(); | ||||
8918 | } | ||||
8919 | |||||
8920 | if (!LHSAA || !RHSAA) { | ||||
8921 | // select (true/false), lhs, rhs | ||||
8922 | auto *OpAA = LHSAA ? LHSAA : RHSAA; | ||||
8923 | |||||
8924 | if (OpAA->undefIsContained()) | ||||
8925 | unionAssumedWithUndef(); | ||||
8926 | else | ||||
8927 | unionAssumed(*OpAA); | ||||
8928 | |||||
8929 | } else if (LHSAA->undefIsContained() && RHSAA->undefIsContained()) { | ||||
8930 | // select i1 *, undef , undef => undef | ||||
8931 | unionAssumedWithUndef(); | ||||
8932 | } else { | ||||
8933 | unionAssumed(*LHSAA); | ||||
8934 | unionAssumed(*RHSAA); | ||||
8935 | } | ||||
8936 | return AssumedBefore == getAssumed() ? ChangeStatus::UNCHANGED | ||||
8937 | : ChangeStatus::CHANGED; | ||||
8938 | } | ||||
8939 | |||||
8940 | ChangeStatus updateWithCastInst(Attributor &A, CastInst *CI) { | ||||
8941 | auto AssumedBefore = getAssumed(); | ||||
8942 | if (!CI->isIntegerCast()) | ||||
8943 | return indicatePessimisticFixpoint(); | ||||
8944 | assert(CI->getNumOperands() == 1 && "Expected cast to be unary!")(static_cast<void> (0)); | ||||
8945 | uint32_t ResultBitWidth = CI->getDestTy()->getIntegerBitWidth(); | ||||
8946 | Value *Src = CI->getOperand(0); | ||||
8947 | |||||
8948 | // Simplify the operand first. | ||||
8949 | bool UsedAssumedInformation = false; | ||||
8950 | const auto &SimplifiedSrc = | ||||
8951 | A.getAssumedSimplified(IRPosition::value(*Src, getCallBaseContext()), | ||||
8952 | *this, UsedAssumedInformation); | ||||
8953 | if (!SimplifiedSrc.hasValue()) | ||||
8954 | return ChangeStatus::UNCHANGED; | ||||
8955 | if (!SimplifiedSrc.getValue()) | ||||
8956 | return indicatePessimisticFixpoint(); | ||||
8957 | Src = *SimplifiedSrc; | ||||
8958 | |||||
8959 | auto &SrcAA = A.getAAFor<AAPotentialValues>(*this, IRPosition::value(*Src), | ||||
8960 | DepClassTy::REQUIRED); | ||||
8961 | if (!SrcAA.isValidState()) | ||||
8962 | return indicatePessimisticFixpoint(); | ||||
8963 | const DenseSet<APInt> &SrcAAPVS = SrcAA.getAssumedSet(); | ||||
8964 | if (SrcAA.undefIsContained()) | ||||
8965 | unionAssumedWithUndef(); | ||||
8966 | else { | ||||
8967 | for (const APInt &S : SrcAAPVS) { | ||||
8968 | APInt T = calculateCastInst(CI, S, ResultBitWidth); | ||||
8969 | unionAssumed(T); | ||||
8970 | } | ||||
8971 | } | ||||
8972 | return AssumedBefore == getAssumed() ? ChangeStatus::UNCHANGED | ||||
8973 | : ChangeStatus::CHANGED; | ||||
8974 | } | ||||
8975 | |||||
8976 | ChangeStatus updateWithBinaryOperator(Attributor &A, BinaryOperator *BinOp) { | ||||
8977 | auto AssumedBefore = getAssumed(); | ||||
8978 | Value *LHS = BinOp->getOperand(0); | ||||
8979 | Value *RHS = BinOp->getOperand(1); | ||||
8980 | |||||
8981 | // Simplify the operands first. | ||||
8982 | bool UsedAssumedInformation = false; | ||||
8983 | const auto &SimplifiedLHS = | ||||
8984 | A.getAssumedSimplified(IRPosition::value(*LHS, getCallBaseContext()), | ||||
8985 | *this, UsedAssumedInformation); | ||||
8986 | if (!SimplifiedLHS.hasValue()) | ||||
8987 | return ChangeStatus::UNCHANGED; | ||||
8988 | if (!SimplifiedLHS.getValue()) | ||||
8989 | return indicatePessimisticFixpoint(); | ||||
8990 | LHS = *SimplifiedLHS; | ||||
8991 | |||||
8992 | const auto &SimplifiedRHS = | ||||
8993 | A.getAssumedSimplified(IRPosition::value(*RHS, getCallBaseContext()), | ||||
8994 | *this, UsedAssumedInformation); | ||||
8995 | if (!SimplifiedRHS.hasValue()) | ||||
8996 | return ChangeStatus::UNCHANGED; | ||||
8997 | if (!SimplifiedRHS.getValue()) | ||||
8998 | return indicatePessimisticFixpoint(); | ||||
8999 | RHS = *SimplifiedRHS; | ||||
9000 | |||||
9001 | if (!LHS->getType()->isIntegerTy() || !RHS->getType()->isIntegerTy()) | ||||
9002 | return indicatePessimisticFixpoint(); | ||||
9003 | |||||
9004 | auto &LHSAA = A.getAAFor<AAPotentialValues>(*this, IRPosition::value(*LHS), | ||||
9005 | DepClassTy::REQUIRED); | ||||
9006 | if (!LHSAA.isValidState()) | ||||
9007 | return indicatePessimisticFixpoint(); | ||||
9008 | |||||
9009 | auto &RHSAA = A.getAAFor<AAPotentialValues>(*this, IRPosition::value(*RHS), | ||||
9010 | DepClassTy::REQUIRED); | ||||
9011 | if (!RHSAA.isValidState()) | ||||
9012 | return indicatePessimisticFixpoint(); | ||||
9013 | |||||
9014 | const DenseSet<APInt> &LHSAAPVS = LHSAA.getAssumedSet(); | ||||
9015 | const DenseSet<APInt> &RHSAAPVS = RHSAA.getAssumedSet(); | ||||
9016 | const APInt Zero = APInt(LHS->getType()->getIntegerBitWidth(), 0); | ||||
9017 | |||||
9018 | // TODO: make use of undef flag to limit potential values aggressively. | ||||
9019 | if (LHSAA.undefIsContained() && RHSAA.undefIsContained()) { | ||||
9020 | if (!calculateBinaryOperatorAndTakeUnion(BinOp, Zero, Zero)) | ||||
9021 | return indicatePessimisticFixpoint(); | ||||
9022 | } else if (LHSAA.undefIsContained()) { | ||||
9023 | for (const APInt &R : RHSAAPVS) { | ||||
9024 | if (!calculateBinaryOperatorAndTakeUnion(BinOp, Zero, R)) | ||||
9025 | return indicatePessimisticFixpoint(); | ||||
9026 | } | ||||
9027 | } else if (RHSAA.undefIsContained()) { | ||||
9028 | for (const APInt &L : LHSAAPVS) { | ||||
9029 | if (!calculateBinaryOperatorAndTakeUnion(BinOp, L, Zero)) | ||||
9030 | return indicatePessimisticFixpoint(); | ||||
9031 | } | ||||
9032 | } else { | ||||
9033 | for (const APInt &L : LHSAAPVS) { | ||||
9034 | for (const APInt &R : RHSAAPVS) { | ||||
9035 | if (!calculateBinaryOperatorAndTakeUnion(BinOp, L, R)) | ||||
9036 | return indicatePessimisticFixpoint(); | ||||
9037 | } | ||||
9038 | } | ||||
9039 | } | ||||
9040 | return AssumedBefore == getAssumed() ? ChangeStatus::UNCHANGED | ||||
9041 | : ChangeStatus::CHANGED; | ||||
9042 | } | ||||
9043 | |||||
9044 | ChangeStatus updateWithPHINode(Attributor &A, PHINode *PHI) { | ||||
9045 | auto AssumedBefore = getAssumed(); | ||||
9046 | for (unsigned u = 0, e = PHI->getNumIncomingValues(); u < e; u++) { | ||||
9047 | Value *IncomingValue = PHI->getIncomingValue(u); | ||||
9048 | |||||
9049 | // Simplify the operand first. | ||||
9050 | bool UsedAssumedInformation = false; | ||||
9051 | const auto &SimplifiedIncomingValue = A.getAssumedSimplified( | ||||
9052 | IRPosition::value(*IncomingValue, getCallBaseContext()), *this, | ||||
9053 | UsedAssumedInformation); | ||||
9054 | if (!SimplifiedIncomingValue.hasValue()) | ||||
9055 | continue; | ||||
9056 | if (!SimplifiedIncomingValue.getValue()) | ||||
9057 | return indicatePessimisticFixpoint(); | ||||
9058 | IncomingValue = *SimplifiedIncomingValue; | ||||
9059 | |||||
9060 | auto &PotentialValuesAA = A.getAAFor<AAPotentialValues>( | ||||
9061 | *this, IRPosition::value(*IncomingValue), DepClassTy::REQUIRED); | ||||
9062 | if (!PotentialValuesAA.isValidState()) | ||||
9063 | return indicatePessimisticFixpoint(); | ||||
9064 | if (PotentialValuesAA.undefIsContained()) | ||||
9065 | unionAssumedWithUndef(); | ||||
9066 | else | ||||
9067 | unionAssumed(PotentialValuesAA.getAssumed()); | ||||
9068 | } | ||||
9069 | return AssumedBefore == getAssumed() ? ChangeStatus::UNCHANGED | ||||
9070 | : ChangeStatus::CHANGED; | ||||
9071 | } | ||||
9072 | |||||
9073 | ChangeStatus updateWithLoad(Attributor &A, LoadInst &L) { | ||||
9074 | if (!L.getType()->isIntegerTy()) | ||||
9075 | return indicatePessimisticFixpoint(); | ||||
9076 | |||||
9077 | auto Union = [&](Value &V) { | ||||
9078 | if (isa<UndefValue>(V)) { | ||||
9079 | unionAssumedWithUndef(); | ||||
9080 | return true; | ||||
9081 | } | ||||
9082 | if (ConstantInt *CI = dyn_cast<ConstantInt>(&V)) { | ||||
9083 | unionAssumed(CI->getValue()); | ||||
9084 | return true; | ||||
9085 | } | ||||
9086 | return false; | ||||
9087 | }; | ||||
9088 | auto AssumedBefore = getAssumed(); | ||||
9089 | |||||
9090 | if (!AAValueSimplifyImpl::handleLoad(A, *this, L, Union)) | ||||
9091 | return indicatePessimisticFixpoint(); | ||||
9092 | |||||
9093 | return AssumedBefore == getAssumed() ? ChangeStatus::UNCHANGED | ||||
9094 | : ChangeStatus::CHANGED; | ||||
9095 | } | ||||
9096 | |||||
9097 | /// See AbstractAttribute::updateImpl(...). | ||||
9098 | ChangeStatus updateImpl(Attributor &A) override { | ||||
9099 | Value &V = getAssociatedValue(); | ||||
9100 | Instruction *I = dyn_cast<Instruction>(&V); | ||||
9101 | |||||
9102 | if (auto *ICI = dyn_cast<ICmpInst>(I)) | ||||
9103 | return updateWithICmpInst(A, ICI); | ||||
9104 | |||||
9105 | if (auto *SI = dyn_cast<SelectInst>(I)) | ||||
9106 | return updateWithSelectInst(A, SI); | ||||
9107 | |||||
9108 | if (auto *CI = dyn_cast<CastInst>(I)) | ||||
9109 | return updateWithCastInst(A, CI); | ||||
9110 | |||||
9111 | if (auto *BinOp = dyn_cast<BinaryOperator>(I)) | ||||
9112 | return updateWithBinaryOperator(A, BinOp); | ||||
9113 | |||||
9114 | if (auto *PHI = dyn_cast<PHINode>(I)) | ||||
9115 | return updateWithPHINode(A, PHI); | ||||
9116 | |||||
9117 | if (auto *L = dyn_cast<LoadInst>(I)) | ||||
9118 | return updateWithLoad(A, *L); | ||||
9119 | |||||
9120 | return indicatePessimisticFixpoint(); | ||||
9121 | } | ||||
9122 | |||||
9123 | /// See AbstractAttribute::trackStatistics() | ||||
9124 | void trackStatistics() const override { | ||||
9125 | STATS_DECLTRACK_FLOATING_ATTR(potential_values){ static llvm::Statistic NumIRFloating_potential_values = {"attributor" , "NumIRFloating_potential_values", ("Number of floating values known to be '" "potential_values" "'")};; ++(NumIRFloating_potential_values ); } | ||||
9126 | } | ||||
9127 | }; | ||||
9128 | |||||
9129 | struct AAPotentialValuesFunction : AAPotentialValuesImpl { | ||||
9130 | AAPotentialValuesFunction(const IRPosition &IRP, Attributor &A) | ||||
9131 | : AAPotentialValuesImpl(IRP, A) {} | ||||
9132 | |||||
9133 | /// See AbstractAttribute::initialize(...). | ||||
9134 | ChangeStatus updateImpl(Attributor &A) override { | ||||
9135 | llvm_unreachable("AAPotentialValues(Function|CallSite)::updateImpl will "__builtin_unreachable() | ||||
9136 | "not be called")__builtin_unreachable(); | ||||
9137 | } | ||||
9138 | |||||
9139 | /// See AbstractAttribute::trackStatistics() | ||||
9140 | void trackStatistics() const override { | ||||
9141 | STATS_DECLTRACK_FN_ATTR(potential_values){ static llvm::Statistic NumIRFunction_potential_values = {"attributor" , "NumIRFunction_potential_values", ("Number of " "functions" " marked '" "potential_values" "'")};; ++(NumIRFunction_potential_values ); } | ||||
9142 | } | ||||
9143 | }; | ||||
9144 | |||||
9145 | struct AAPotentialValuesCallSite : AAPotentialValuesFunction { | ||||
9146 | AAPotentialValuesCallSite(const IRPosition &IRP, Attributor &A) | ||||
9147 | : AAPotentialValuesFunction(IRP, A) {} | ||||
9148 | |||||
9149 | /// See AbstractAttribute::trackStatistics() | ||||
9150 | void trackStatistics() const override { | ||||
9151 | STATS_DECLTRACK_CS_ATTR(potential_values){ static llvm::Statistic NumIRCS_potential_values = {"attributor" , "NumIRCS_potential_values", ("Number of " "call site" " marked '" "potential_values" "'")};; ++(NumIRCS_potential_values); } | ||||
9152 | } | ||||
9153 | }; | ||||
9154 | |||||
9155 | struct AAPotentialValuesCallSiteReturned | ||||
9156 | : AACallSiteReturnedFromReturned<AAPotentialValues, AAPotentialValuesImpl> { | ||||
9157 | AAPotentialValuesCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
9158 | : AACallSiteReturnedFromReturned<AAPotentialValues, | ||||
9159 | AAPotentialValuesImpl>(IRP, A) {} | ||||
9160 | |||||
9161 | /// See AbstractAttribute::trackStatistics() | ||||
9162 | void trackStatistics() const override { | ||||
9163 | STATS_DECLTRACK_CSRET_ATTR(potential_values){ static llvm::Statistic NumIRCSReturn_potential_values = {"attributor" , "NumIRCSReturn_potential_values", ("Number of " "call site returns" " marked '" "potential_values" "'")};; ++(NumIRCSReturn_potential_values ); } | ||||
9164 | } | ||||
9165 | }; | ||||
9166 | |||||
9167 | struct AAPotentialValuesCallSiteArgument : AAPotentialValuesFloating { | ||||
9168 | AAPotentialValuesCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
9169 | : AAPotentialValuesFloating(IRP, A) {} | ||||
9170 | |||||
9171 | /// See AbstractAttribute::initialize(..). | ||||
9172 | void initialize(Attributor &A) override { | ||||
9173 | AAPotentialValuesImpl::initialize(A); | ||||
9174 | if (isAtFixpoint()) | ||||
9175 | return; | ||||
9176 | |||||
9177 | Value &V = getAssociatedValue(); | ||||
9178 | |||||
9179 | if (auto *C = dyn_cast<ConstantInt>(&V)) { | ||||
9180 | unionAssumed(C->getValue()); | ||||
9181 | indicateOptimisticFixpoint(); | ||||
9182 | return; | ||||
9183 | } | ||||
9184 | |||||
9185 | if (isa<UndefValue>(&V)) { | ||||
9186 | unionAssumedWithUndef(); | ||||
9187 | indicateOptimisticFixpoint(); | ||||
9188 | return; | ||||
9189 | } | ||||
9190 | } | ||||
9191 | |||||
9192 | /// See AbstractAttribute::updateImpl(...). | ||||
9193 | ChangeStatus updateImpl(Attributor &A) override { | ||||
9194 | Value &V = getAssociatedValue(); | ||||
9195 | auto AssumedBefore = getAssumed(); | ||||
9196 | auto &AA = A.getAAFor<AAPotentialValues>(*this, IRPosition::value(V), | ||||
9197 | DepClassTy::REQUIRED); | ||||
9198 | const auto &S = AA.getAssumed(); | ||||
9199 | unionAssumed(S); | ||||
9200 | return AssumedBefore == getAssumed() ? ChangeStatus::UNCHANGED | ||||
9201 | : ChangeStatus::CHANGED; | ||||
9202 | } | ||||
9203 | |||||
9204 | /// See AbstractAttribute::trackStatistics() | ||||
9205 | void trackStatistics() const override { | ||||
9206 | STATS_DECLTRACK_CSARG_ATTR(potential_values){ static llvm::Statistic NumIRCSArguments_potential_values = { "attributor", "NumIRCSArguments_potential_values", ("Number of " "call site arguments" " marked '" "potential_values" "'")};; ++(NumIRCSArguments_potential_values); } | ||||
9207 | } | ||||
9208 | }; | ||||
9209 | |||||
9210 | /// ------------------------ NoUndef Attribute --------------------------------- | ||||
9211 | struct AANoUndefImpl : AANoUndef { | ||||
9212 | AANoUndefImpl(const IRPosition &IRP, Attributor &A) : AANoUndef(IRP, A) {} | ||||
9213 | |||||
9214 | /// See AbstractAttribute::initialize(...). | ||||
9215 | void initialize(Attributor &A) override { | ||||
9216 | if (getIRPosition().hasAttr({Attribute::NoUndef})) { | ||||
9217 | indicateOptimisticFixpoint(); | ||||
9218 | return; | ||||
9219 | } | ||||
9220 | Value &V = getAssociatedValue(); | ||||
9221 | if (isa<UndefValue>(V)) | ||||
9222 | indicatePessimisticFixpoint(); | ||||
9223 | else if (isa<FreezeInst>(V)) | ||||
9224 | indicateOptimisticFixpoint(); | ||||
9225 | else if (getPositionKind() != IRPosition::IRP_RETURNED && | ||||
9226 | isGuaranteedNotToBeUndefOrPoison(&V)) | ||||
9227 | indicateOptimisticFixpoint(); | ||||
9228 | else | ||||
9229 | AANoUndef::initialize(A); | ||||
9230 | } | ||||
9231 | |||||
9232 | /// See followUsesInMBEC | ||||
9233 | bool followUseInMBEC(Attributor &A, const Use *U, const Instruction *I, | ||||
9234 | AANoUndef::StateType &State) { | ||||
9235 | const Value *UseV = U->get(); | ||||
9236 | const DominatorTree *DT = nullptr; | ||||
9237 | AssumptionCache *AC = nullptr; | ||||
9238 | InformationCache &InfoCache = A.getInfoCache(); | ||||
9239 | if (Function *F = getAnchorScope()) { | ||||
9240 | DT = InfoCache.getAnalysisResultForFunction<DominatorTreeAnalysis>(*F); | ||||
9241 | AC = InfoCache.getAnalysisResultForFunction<AssumptionAnalysis>(*F); | ||||
9242 | } | ||||
9243 | State.setKnown(isGuaranteedNotToBeUndefOrPoison(UseV, AC, I, DT)); | ||||
9244 | bool TrackUse = false; | ||||
9245 | // Track use for instructions which must produce undef or poison bits when | ||||
9246 | // at least one operand contains such bits. | ||||
9247 | if (isa<CastInst>(*I) || isa<GetElementPtrInst>(*I)) | ||||
9248 | TrackUse = true; | ||||
9249 | return TrackUse; | ||||
9250 | } | ||||
9251 | |||||
9252 | /// See AbstractAttribute::getAsStr(). | ||||
9253 | const std::string getAsStr() const override { | ||||
9254 | return getAssumed() ? "noundef" : "may-undef-or-poison"; | ||||
9255 | } | ||||
9256 | |||||
9257 | ChangeStatus manifest(Attributor &A) override { | ||||
9258 | // We don't manifest noundef attribute for dead positions because the | ||||
9259 | // associated values with dead positions would be replaced with undef | ||||
9260 | // values. | ||||
9261 | bool UsedAssumedInformation = false; | ||||
9262 | if (A.isAssumedDead(getIRPosition(), nullptr, nullptr, | ||||
9263 | UsedAssumedInformation)) | ||||
9264 | return ChangeStatus::UNCHANGED; | ||||
9265 | // A position whose simplified value does not have any value is | ||||
9266 | // considered to be dead. We don't manifest noundef in such positions for | ||||
9267 | // the same reason above. | ||||
9268 | if (!A.getAssumedSimplified(getIRPosition(), *this, UsedAssumedInformation) | ||||
9269 | .hasValue()) | ||||
9270 | return ChangeStatus::UNCHANGED; | ||||
9271 | return AANoUndef::manifest(A); | ||||
9272 | } | ||||
9273 | }; | ||||
9274 | |||||
9275 | struct AANoUndefFloating : public AANoUndefImpl { | ||||
9276 | AANoUndefFloating(const IRPosition &IRP, Attributor &A) | ||||
9277 | : AANoUndefImpl(IRP, A) {} | ||||
9278 | |||||
9279 | /// See AbstractAttribute::initialize(...). | ||||
9280 | void initialize(Attributor &A) override { | ||||
9281 | AANoUndefImpl::initialize(A); | ||||
9282 | if (!getState().isAtFixpoint()) | ||||
9283 | if (Instruction *CtxI = getCtxI()) | ||||
9284 | followUsesInMBEC(*this, A, getState(), *CtxI); | ||||
9285 | } | ||||
9286 | |||||
9287 | /// See AbstractAttribute::updateImpl(...). | ||||
9288 | ChangeStatus updateImpl(Attributor &A) override { | ||||
9289 | auto VisitValueCB = [&](Value &V, const Instruction *CtxI, | ||||
9290 | AANoUndef::StateType &T, bool Stripped) -> bool { | ||||
9291 | const auto &AA = A.getAAFor<AANoUndef>(*this, IRPosition::value(V), | ||||
9292 | DepClassTy::REQUIRED); | ||||
9293 | if (!Stripped && this == &AA) { | ||||
9294 | T.indicatePessimisticFixpoint(); | ||||
9295 | } else { | ||||
9296 | const AANoUndef::StateType &S = | ||||
9297 | static_cast<const AANoUndef::StateType &>(AA.getState()); | ||||
9298 | T ^= S; | ||||
9299 | } | ||||
9300 | return T.isValidState(); | ||||
9301 | }; | ||||
9302 | |||||
9303 | StateType T; | ||||
9304 | if (!genericValueTraversal<StateType>(A, getIRPosition(), *this, T, | ||||
| |||||
9305 | VisitValueCB, getCtxI())) | ||||
9306 | return indicatePessimisticFixpoint(); | ||||
9307 | |||||
9308 | return clampStateAndIndicateChange(getState(), T); | ||||
9309 | } | ||||
9310 | |||||
9311 | /// See AbstractAttribute::trackStatistics() | ||||
9312 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(noundef){ static llvm::Statistic NumIRFunctionReturn_noundef = {"attributor" , "NumIRFunctionReturn_noundef", ("Number of " "function returns" " marked '" "noundef" "'")};; ++(NumIRFunctionReturn_noundef ); } } | ||||
9313 | }; | ||||
9314 | |||||
9315 | struct AANoUndefReturned final | ||||
9316 | : AAReturnedFromReturnedValues<AANoUndef, AANoUndefImpl> { | ||||
9317 | AANoUndefReturned(const IRPosition &IRP, Attributor &A) | ||||
9318 | : AAReturnedFromReturnedValues<AANoUndef, AANoUndefImpl>(IRP, A) {} | ||||
9319 | |||||
9320 | /// See AbstractAttribute::trackStatistics() | ||||
9321 | void trackStatistics() const override { STATS_DECLTRACK_FNRET_ATTR(noundef){ static llvm::Statistic NumIRFunctionReturn_noundef = {"attributor" , "NumIRFunctionReturn_noundef", ("Number of " "function returns" " marked '" "noundef" "'")};; ++(NumIRFunctionReturn_noundef ); } } | ||||
9322 | }; | ||||
9323 | |||||
9324 | struct AANoUndefArgument final | ||||
9325 | : AAArgumentFromCallSiteArguments<AANoUndef, AANoUndefImpl> { | ||||
9326 | AANoUndefArgument(const IRPosition &IRP, Attributor &A) | ||||
9327 | : AAArgumentFromCallSiteArguments<AANoUndef, AANoUndefImpl>(IRP, A) {} | ||||
9328 | |||||
9329 | /// See AbstractAttribute::trackStatistics() | ||||
9330 | void trackStatistics() const override { STATS_DECLTRACK_ARG_ATTR(noundef){ static llvm::Statistic NumIRArguments_noundef = {"attributor" , "NumIRArguments_noundef", ("Number of " "arguments" " marked '" "noundef" "'")};; ++(NumIRArguments_noundef); } } | ||||
9331 | }; | ||||
9332 | |||||
9333 | struct AANoUndefCallSiteArgument final : AANoUndefFloating { | ||||
9334 | AANoUndefCallSiteArgument(const IRPosition &IRP, Attributor &A) | ||||
9335 | : AANoUndefFloating(IRP, A) {} | ||||
9336 | |||||
9337 | /// See AbstractAttribute::trackStatistics() | ||||
9338 | void trackStatistics() const override { STATS_DECLTRACK_CSARG_ATTR(noundef){ static llvm::Statistic NumIRCSArguments_noundef = {"attributor" , "NumIRCSArguments_noundef", ("Number of " "call site arguments" " marked '" "noundef" "'")};; ++(NumIRCSArguments_noundef); } } | ||||
9339 | }; | ||||
9340 | |||||
9341 | struct AANoUndefCallSiteReturned final | ||||
9342 | : AACallSiteReturnedFromReturned<AANoUndef, AANoUndefImpl> { | ||||
9343 | AANoUndefCallSiteReturned(const IRPosition &IRP, Attributor &A) | ||||
9344 | : AACallSiteReturnedFromReturned<AANoUndef, AANoUndefImpl>(IRP, A) {} | ||||
9345 | |||||
9346 | /// See AbstractAttribute::trackStatistics() | ||||
9347 | void trackStatistics() const override { STATS_DECLTRACK_CSRET_ATTR(noundef){ static llvm::Statistic NumIRCSReturn_noundef = {"attributor" , "NumIRCSReturn_noundef", ("Number of " "call site returns" " marked '" "noundef" "'")};; ++(NumIRCSReturn_noundef); } } | ||||
9348 | }; | ||||
9349 | |||||
9350 | struct AACallEdgesFunction : public AACallEdges { | ||||
9351 | AACallEdgesFunction(const IRPosition &IRP, Attributor &A) | ||||
9352 | : AACallEdges(IRP, A) {} | ||||
9353 | |||||
9354 | /// See AbstractAttribute::updateImpl(...). | ||||
9355 | ChangeStatus updateImpl(Attributor &A) override { | ||||
9356 | ChangeStatus Change = ChangeStatus::UNCHANGED; | ||||
9357 | bool OldHasUnknownCallee = HasUnknownCallee; | ||||
9358 | bool OldHasUnknownCalleeNonAsm = HasUnknownCalleeNonAsm; | ||||
9359 | |||||
9360 | auto AddCalledFunction = [&](Function *Fn) { | ||||
9361 | if (CalledFunctions.insert(Fn)) { | ||||
9362 | Change = ChangeStatus::CHANGED; | ||||
9363 | LLVM_DEBUG(dbgs() << "[AACallEdges] New call edge: " << Fn->getName()do { } while (false) | ||||
9364 | << "\n")do { } while (false); | ||||
9365 | } | ||||
9366 | }; | ||||
9367 | |||||
9368 | auto VisitValue = [&](Value &V, const Instruction *CtxI, bool &HasUnknown, | ||||
9369 | bool Stripped) -> bool { | ||||
9370 | if (Function *Fn = dyn_cast<Function>(&V)) { | ||||
9371 | AddCalledFunction(Fn); | ||||
9372 | } else { | ||||
9373 | LLVM_DEBUG(dbgs() << "[AACallEdges] Unrecognized value: " << V << "\n")do { } while (false); | ||||
9374 | HasUnknown = true; | ||||
9375 | HasUnknownCalleeNonAsm = true; | ||||
9376 | } | ||||
9377 | |||||
9378 | // Explore all values. | ||||
9379 | return true; | ||||
9380 | }; | ||||
9381 | |||||
9382 | // Process any value that we might call. | ||||
9383 | auto ProcessCalledOperand = [&](Value *V, Instruction *Ctx) { | ||||
9384 | if (!genericValueTraversal<bool>(A, IRPosition::value(*V), *this, | ||||
9385 | HasUnknownCallee, VisitValue, nullptr, | ||||
9386 | false)) { | ||||
9387 | // If we haven't gone through all values, assume that there are unknown | ||||
9388 | // callees. | ||||
9389 | HasUnknownCallee = true; | ||||
9390 | HasUnknownCalleeNonAsm = true; | ||||
9391 | } | ||||
9392 | }; | ||||
9393 | |||||
9394 | auto ProcessCallInst = [&](Instruction &Inst) { | ||||
9395 | CallBase &CB = static_cast<CallBase &>(Inst); | ||||
9396 | if (CB.isInlineAsm()) { | ||||
9397 | HasUnknownCallee = true; | ||||
9398 | return true; | ||||
9399 | } | ||||
9400 | |||||
9401 | // Process callee metadata if available. | ||||
9402 | if (auto *MD = Inst.getMetadata(LLVMContext::MD_callees)) { | ||||
9403 | for (auto &Op : MD->operands()) { | ||||
9404 | Function *Callee = mdconst::extract_or_null<Function>(Op); | ||||
9405 | if (Callee) | ||||
9406 | AddCalledFunction(Callee); | ||||
9407 | } | ||||
9408 | // Callees metadata grantees that the called function is one of its | ||||
9409 | // operands, So we are done. | ||||
9410 | return true; | ||||
9411 | } | ||||
9412 | |||||
9413 | // The most simple case. | ||||
9414 | ProcessCalledOperand(CB.getCalledOperand(), &Inst); | ||||
9415 | |||||
9416 | // Process callback functions. | ||||
9417 | SmallVector<const Use *, 4u> CallbackUses; | ||||
9418 | AbstractCallSite::getCallbackUses(CB, CallbackUses); | ||||
9419 | for (const Use *U : CallbackUses) | ||||
9420 | ProcessCalledOperand(U->get(), &Inst); | ||||
9421 | |||||
9422 | return true; | ||||
9423 | }; | ||||
9424 | |||||
9425 | // Visit all callable instructions. | ||||
9426 | bool UsedAssumedInformation = false; | ||||
9427 | if (!A.checkForAllCallLikeInstructions(ProcessCallInst, *this, | ||||
9428 | UsedAssumedInformation)) { | ||||
9429 | // If we haven't looked at all call like instructions, assume that there | ||||
9430 | // are unknown callees. | ||||
9431 | HasUnknownCallee = true; | ||||
9432 | HasUnknownCalleeNonAsm = true; | ||||
9433 | } | ||||
9434 | |||||
9435 | // Track changes. | ||||
9436 | if (OldHasUnknownCallee != HasUnknownCallee || | ||||
9437 | OldHasUnknownCalleeNonAsm != HasUnknownCalleeNonAsm) | ||||
9438 | Change = ChangeStatus::CHANGED; | ||||
9439 | |||||
9440 | return Change; | ||||
9441 | } | ||||
9442 | |||||
9443 | virtual const SetVector<Function *> &getOptimisticEdges() const override { | ||||
9444 | return CalledFunctions; | ||||
9445 | }; | ||||
9446 | |||||
9447 | virtual bool hasUnknownCallee() const override { return HasUnknownCallee; } | ||||
9448 | |||||
9449 | virtual bool hasNonAsmUnknownCallee() const override { | ||||
9450 | return HasUnknownCalleeNonAsm; | ||||
9451 | } | ||||
9452 | |||||
9453 | const std::string getAsStr() const override { | ||||
9454 | return "CallEdges[" + std::to_string(HasUnknownCallee) + "," + | ||||
9455 | std::to_string(CalledFunctions.size()) + "]"; | ||||
9456 | } | ||||
9457 | |||||
9458 | void trackStatistics() const override {} | ||||
9459 | |||||
9460 | /// Optimistic set of functions that might be called by this function. | ||||
9461 | SetVector<Function *> CalledFunctions; | ||||
9462 | |||||
9463 | /// Is there any call with a unknown callee. | ||||
9464 | bool HasUnknownCallee = false; | ||||
9465 | |||||
9466 | /// Is there any call with a unknown callee, excluding any inline asm. | ||||
9467 | bool HasUnknownCalleeNonAsm = false; | ||||
9468 | }; | ||||
9469 | |||||
9470 | struct AAFunctionReachabilityFunction : public AAFunctionReachability { | ||||
9471 | AAFunctionReachabilityFunction(const IRPosition &IRP, Attributor &A) | ||||
9472 | : AAFunctionReachability(IRP, A) {} | ||||
9473 | |||||
9474 | bool canReach(Attributor &A, Function *Fn) const override { | ||||
9475 | // Assume that we can reach any function if we can reach a call with | ||||
9476 | // unknown callee. | ||||
9477 | if (CanReachUnknownCallee) | ||||
9478 | return true; | ||||
9479 | |||||
9480 | if (ReachableQueries.count(Fn)) | ||||
9481 | return true; | ||||
9482 | |||||
9483 | if (UnreachableQueries.count(Fn)) | ||||
9484 | return false; | ||||
9485 | |||||
9486 | const AACallEdges &AAEdges = | ||||
9487 | A.getAAFor<AACallEdges>(*this, getIRPosition(), DepClassTy::REQUIRED); | ||||
9488 | |||||
9489 | const SetVector<Function *> &Edges = AAEdges.getOptimisticEdges(); | ||||
9490 | bool Result = checkIfReachable(A, Edges, Fn); | ||||
9491 | |||||
9492 | // Attributor returns attributes as const, so this function has to be | ||||
9493 | // const for users of this attribute to use it without having to do | ||||
9494 | // a const_cast. | ||||
9495 | // This is a hack for us to be able to cache queries. | ||||
9496 | auto *NonConstThis = const_cast<AAFunctionReachabilityFunction *>(this); | ||||
9497 | |||||
9498 | if (Result) | ||||
9499 | NonConstThis->ReachableQueries.insert(Fn); | ||||
9500 | else | ||||
9501 | NonConstThis->UnreachableQueries.insert(Fn); | ||||
9502 | |||||
9503 | return Result; | ||||
9504 | } | ||||
9505 | |||||
9506 | /// See AbstractAttribute::updateImpl(...). | ||||
9507 | ChangeStatus updateImpl(Attributor &A) override { | ||||
9508 | if (CanReachUnknownCallee) | ||||
9509 | return ChangeStatus::UNCHANGED; | ||||
9510 | |||||
9511 | const AACallEdges &AAEdges = | ||||
9512 | A.getAAFor<AACallEdges>(*this, getIRPosition(), DepClassTy::REQUIRED); | ||||
9513 | const SetVector<Function *> &Edges = AAEdges.getOptimisticEdges(); | ||||
9514 | ChangeStatus Change = ChangeStatus::UNCHANGED; | ||||
9515 | |||||
9516 | if (AAEdges.hasUnknownCallee()) { | ||||
9517 | bool OldCanReachUnknown = CanReachUnknownCallee; | ||||
9518 | CanReachUnknownCallee = true; | ||||
9519 | return OldCanReachUnknown ? ChangeStatus::UNCHANGED | ||||
9520 | : ChangeStatus::CHANGED; | ||||
9521 | } | ||||
9522 | |||||
9523 | // Check if any of the unreachable functions become reachable. | ||||
9524 | for (auto Current = UnreachableQueries.begin(); | ||||
9525 | Current != UnreachableQueries.end();) { | ||||
9526 | if (!checkIfReachable(A, Edges, *Current)) { | ||||
9527 | Current++; | ||||
9528 | continue; | ||||
9529 | } | ||||
9530 | ReachableQueries.insert(*Current); | ||||
9531 | UnreachableQueries.erase(*Current++); | ||||
9532 | Change = ChangeStatus::CHANGED; | ||||
9533 | } | ||||
9534 | |||||
9535 | return Change; | ||||
9536 | } | ||||
9537 | |||||
9538 | const std::string getAsStr() const override { | ||||
9539 | size_t QueryCount = ReachableQueries.size() + UnreachableQueries.size(); | ||||
9540 | |||||
9541 | return "FunctionReachability [" + std::to_string(ReachableQueries.size()) + | ||||
9542 | "," + std::to_string(QueryCount) + "]"; | ||||
9543 | } | ||||
9544 | |||||
9545 | void trackStatistics() const override {} | ||||
9546 | |||||
9547 | private: | ||||
9548 | bool canReachUnknownCallee() const override { return CanReachUnknownCallee; } | ||||
9549 | |||||
9550 | bool checkIfReachable(Attributor &A, const SetVector<Function *> &Edges, | ||||
9551 | Function *Fn) const { | ||||
9552 | if (Edges.count(Fn)) | ||||
9553 | return true; | ||||
9554 | |||||
9555 | for (Function *Edge : Edges) { | ||||
9556 | // We don't need a dependency if the result is reachable. | ||||
9557 | const AAFunctionReachability &EdgeReachability = | ||||
9558 | A.getAAFor<AAFunctionReachability>(*this, IRPosition::function(*Edge), | ||||
9559 | DepClassTy::NONE); | ||||
9560 | |||||
9561 | if (EdgeReachability.canReach(A, Fn)) | ||||
9562 | return true; | ||||
9563 | } | ||||
9564 | for (Function *Fn : Edges) | ||||
9565 | A.getAAFor<AAFunctionReachability>(*this, IRPosition::function(*Fn), | ||||
9566 | DepClassTy::REQUIRED); | ||||
9567 | |||||
9568 | return false; | ||||
9569 | } | ||||
9570 | |||||
9571 | /// Set of functions that we know for sure is reachable. | ||||
9572 | SmallPtrSet<Function *, 8> ReachableQueries; | ||||
9573 | |||||
9574 | /// Set of functions that are unreachable, but might become reachable. | ||||
9575 | SmallPtrSet<Function *, 8> UnreachableQueries; | ||||
9576 | |||||
9577 | /// If we can reach a function with a call to a unknown function we assume | ||||
9578 | /// that we can reach any function. | ||||
9579 | bool CanReachUnknownCallee = false; | ||||
9580 | }; | ||||
9581 | |||||
9582 | } // namespace | ||||
9583 | |||||
9584 | AACallGraphNode *AACallEdgeIterator::operator*() const { | ||||
9585 | return static_cast<AACallGraphNode *>(const_cast<AACallEdges *>( | ||||
9586 | &A.getOrCreateAAFor<AACallEdges>(IRPosition::function(**I)))); | ||||
9587 | } | ||||
9588 | |||||
9589 | void AttributorCallGraph::print() { llvm::WriteGraph(outs(), this); } | ||||
9590 | |||||
9591 | const char AAReturnedValues::ID = 0; | ||||
9592 | const char AANoUnwind::ID = 0; | ||||
9593 | const char AANoSync::ID = 0; | ||||
9594 | const char AANoFree::ID = 0; | ||||
9595 | const char AANonNull::ID = 0; | ||||
9596 | const char AANoRecurse::ID = 0; | ||||
9597 | const char AAWillReturn::ID = 0; | ||||
9598 | const char AAUndefinedBehavior::ID = 0; | ||||
9599 | const char AANoAlias::ID = 0; | ||||
9600 | const char AAReachability::ID = 0; | ||||
9601 | const char AANoReturn::ID = 0; | ||||
9602 | const char AAIsDead::ID = 0; | ||||
9603 | const char AADereferenceable::ID = 0; | ||||
9604 | const char AAAlign::ID = 0; | ||||
9605 | const char AANoCapture::ID = 0; | ||||
9606 | const char AAValueSimplify::ID = 0; | ||||
9607 | const char AAHeapToStack::ID = 0; | ||||
9608 | const char AAPrivatizablePtr::ID = 0; | ||||
9609 | const char AAMemoryBehavior::ID = 0; | ||||
9610 | const char AAMemoryLocation::ID = 0; | ||||
9611 | const char AAValueConstantRange::ID = 0; | ||||
9612 | const char AAPotentialValues::ID = 0; | ||||
9613 | const char AANoUndef::ID = 0; | ||||
9614 | const char AACallEdges::ID = 0; | ||||
9615 | const char AAFunctionReachability::ID = 0; | ||||
9616 | const char AAPointerInfo::ID = 0; | ||||
9617 | |||||
9618 | // Macro magic to create the static generator function for attributes that | ||||
9619 | // follow the naming scheme. | ||||
9620 | |||||
9621 | #define SWITCH_PK_INV(CLASS, PK, POS_NAME) \ | ||||
9622 | case IRPosition::PK: \ | ||||
9623 | llvm_unreachable("Cannot create " #CLASS " for a " POS_NAME " position!")__builtin_unreachable(); | ||||
9624 | |||||
9625 | #define SWITCH_PK_CREATE(CLASS, IRP, PK, SUFFIX) \ | ||||
9626 | case IRPosition::PK: \ | ||||
9627 | AA = new (A.Allocator) CLASS##SUFFIX(IRP, A); \ | ||||
9628 | ++NumAAs; \ | ||||
9629 | break; | ||||
9630 | |||||
9631 | #define CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION(CLASS) \ | ||||
9632 | CLASS &CLASS::createForPosition(const IRPosition &IRP, Attributor &A) { \ | ||||
9633 | CLASS *AA = nullptr; \ | ||||
9634 | switch (IRP.getPositionKind()) { \ | ||||
9635 | SWITCH_PK_INV(CLASS, IRP_INVALID, "invalid") \ | ||||
9636 | SWITCH_PK_INV(CLASS, IRP_FLOAT, "floating") \ | ||||
9637 | SWITCH_PK_INV(CLASS, IRP_ARGUMENT, "argument") \ | ||||
9638 | SWITCH_PK_INV(CLASS, IRP_RETURNED, "returned") \ | ||||
9639 | SWITCH_PK_INV(CLASS, IRP_CALL_SITE_RETURNED, "call site returned") \ | ||||
9640 | SWITCH_PK_INV(CLASS, IRP_CALL_SITE_ARGUMENT, "call site argument") \ | ||||
9641 | SWITCH_PK_CREATE(CLASS, IRP, IRP_FUNCTION, Function) \ | ||||
9642 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE, CallSite) \ | ||||
9643 | } \ | ||||
9644 | return *AA; \ | ||||
9645 | } | ||||
9646 | |||||
9647 | #define CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(CLASS) \ | ||||
9648 | CLASS &CLASS::createForPosition(const IRPosition &IRP, Attributor &A) { \ | ||||
9649 | CLASS *AA = nullptr; \ | ||||
9650 | switch (IRP.getPositionKind()) { \ | ||||
9651 | SWITCH_PK_INV(CLASS, IRP_INVALID, "invalid") \ | ||||
9652 | SWITCH_PK_INV(CLASS, IRP_FUNCTION, "function") \ | ||||
9653 | SWITCH_PK_INV(CLASS, IRP_CALL_SITE, "call site") \ | ||||
9654 | SWITCH_PK_CREATE(CLASS, IRP, IRP_FLOAT, Floating) \ | ||||
9655 | SWITCH_PK_CREATE(CLASS, IRP, IRP_ARGUMENT, Argument) \ | ||||
9656 | SWITCH_PK_CREATE(CLASS, IRP, IRP_RETURNED, Returned) \ | ||||
9657 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE_RETURNED, CallSiteReturned) \ | ||||
9658 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE_ARGUMENT, CallSiteArgument) \ | ||||
9659 | } \ | ||||
9660 | return *AA; \ | ||||
9661 | } | ||||
9662 | |||||
9663 | #define CREATE_ALL_ABSTRACT_ATTRIBUTE_FOR_POSITION(CLASS) \ | ||||
9664 | CLASS &CLASS::createForPosition(const IRPosition &IRP, Attributor &A) { \ | ||||
9665 | CLASS *AA = nullptr; \ | ||||
9666 | switch (IRP.getPositionKind()) { \ | ||||
9667 | SWITCH_PK_INV(CLASS, IRP_INVALID, "invalid") \ | ||||
9668 | SWITCH_PK_CREATE(CLASS, IRP, IRP_FUNCTION, Function) \ | ||||
9669 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE, CallSite) \ | ||||
9670 | SWITCH_PK_CREATE(CLASS, IRP, IRP_FLOAT, Floating) \ | ||||
9671 | SWITCH_PK_CREATE(CLASS, IRP, IRP_ARGUMENT, Argument) \ | ||||
9672 | SWITCH_PK_CREATE(CLASS, IRP, IRP_RETURNED, Returned) \ | ||||
9673 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE_RETURNED, CallSiteReturned) \ | ||||
9674 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE_ARGUMENT, CallSiteArgument) \ | ||||
9675 | } \ | ||||
9676 | return *AA; \ | ||||
9677 | } | ||||
9678 | |||||
9679 | #define CREATE_FUNCTION_ONLY_ABSTRACT_ATTRIBUTE_FOR_POSITION(CLASS) \ | ||||
9680 | CLASS &CLASS::createForPosition(const IRPosition &IRP, Attributor &A) { \ | ||||
9681 | CLASS *AA = nullptr; \ | ||||
9682 | switch (IRP.getPositionKind()) { \ | ||||
9683 | SWITCH_PK_INV(CLASS, IRP_INVALID, "invalid") \ | ||||
9684 | SWITCH_PK_INV(CLASS, IRP_ARGUMENT, "argument") \ | ||||
9685 | SWITCH_PK_INV(CLASS, IRP_FLOAT, "floating") \ | ||||
9686 | SWITCH_PK_INV(CLASS, IRP_RETURNED, "returned") \ | ||||
9687 | SWITCH_PK_INV(CLASS, IRP_CALL_SITE_RETURNED, "call site returned") \ | ||||
9688 | SWITCH_PK_INV(CLASS, IRP_CALL_SITE_ARGUMENT, "call site argument") \ | ||||
9689 | SWITCH_PK_INV(CLASS, IRP_CALL_SITE, "call site") \ | ||||
9690 | SWITCH_PK_CREATE(CLASS, IRP, IRP_FUNCTION, Function) \ | ||||
9691 | } \ | ||||
9692 | return *AA; \ | ||||
9693 | } | ||||
9694 | |||||
9695 | #define CREATE_NON_RET_ABSTRACT_ATTRIBUTE_FOR_POSITION(CLASS) \ | ||||
9696 | CLASS &CLASS::createForPosition(const IRPosition &IRP, Attributor &A) { \ | ||||
9697 | CLASS *AA = nullptr; \ | ||||
9698 | switch (IRP.getPositionKind()) { \ | ||||
9699 | SWITCH_PK_INV(CLASS, IRP_INVALID, "invalid") \ | ||||
9700 | SWITCH_PK_INV(CLASS, IRP_RETURNED, "returned") \ | ||||
9701 | SWITCH_PK_CREATE(CLASS, IRP, IRP_FUNCTION, Function) \ | ||||
9702 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE, CallSite) \ | ||||
9703 | SWITCH_PK_CREATE(CLASS, IRP, IRP_FLOAT, Floating) \ | ||||
9704 | SWITCH_PK_CREATE(CLASS, IRP, IRP_ARGUMENT, Argument) \ | ||||
9705 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE_RETURNED, CallSiteReturned) \ | ||||
9706 | SWITCH_PK_CREATE(CLASS, IRP, IRP_CALL_SITE_ARGUMENT, CallSiteArgument) \ | ||||
9707 | } \ | ||||
9708 | return *AA; \ | ||||
9709 | } | ||||
9710 | |||||
9711 | CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANoUnwind) | ||||
9712 | CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANoSync) | ||||
9713 | CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANoRecurse) | ||||
9714 | CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAWillReturn) | ||||
9715 | CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANoReturn) | ||||
9716 | CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAReturnedValues) | ||||
9717 | CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAMemoryLocation) | ||||
9718 | |||||
9719 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANonNull) | ||||
9720 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANoAlias) | ||||
9721 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAPrivatizablePtr) | ||||
9722 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AADereferenceable) | ||||
9723 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAAlign) | ||||
9724 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANoCapture) | ||||
9725 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAValueConstantRange) | ||||
9726 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAPotentialValues) | ||||
9727 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANoUndef) | ||||
9728 | CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAPointerInfo) | ||||
9729 | |||||
9730 | CREATE_ALL_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAValueSimplify) | ||||
9731 | CREATE_ALL_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAIsDead) | ||||
9732 | CREATE_ALL_ABSTRACT_ATTRIBUTE_FOR_POSITION(AANoFree) | ||||
9733 | |||||
9734 | CREATE_FUNCTION_ONLY_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAHeapToStack) | ||||
9735 | CREATE_FUNCTION_ONLY_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAReachability) | ||||
9736 | CREATE_FUNCTION_ONLY_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAUndefinedBehavior) | ||||
9737 | CREATE_FUNCTION_ONLY_ABSTRACT_ATTRIBUTE_FOR_POSITION(AACallEdges) | ||||
9738 | CREATE_FUNCTION_ONLY_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAFunctionReachability) | ||||
9739 | |||||
9740 | CREATE_NON_RET_ABSTRACT_ATTRIBUTE_FOR_POSITION(AAMemoryBehavior) | ||||
9741 | |||||
9742 | #undef CREATE_FUNCTION_ONLY_ABSTRACT_ATTRIBUTE_FOR_POSITION | ||||
9743 | #undef CREATE_FUNCTION_ABSTRACT_ATTRIBUTE_FOR_POSITION | ||||
9744 | #undef CREATE_NON_RET_ABSTRACT_ATTRIBUTE_FOR_POSITION | ||||
9745 | #undef CREATE_VALUE_ABSTRACT_ATTRIBUTE_FOR_POSITION | ||||
9746 | #undef CREATE_ALL_ABSTRACT_ATTRIBUTE_FOR_POSITION | ||||
9747 | #undef SWITCH_PK_CREATE | ||||
9748 | #undef SWITCH_PK_INV |
1 | //===- llvm/ADT/SmallVector.h - 'Normally small' vectors --------*- C++ -*-===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // |
9 | // This file defines the SmallVector class. |
10 | // |
11 | //===----------------------------------------------------------------------===// |
12 | |
13 | #ifndef LLVM_ADT_SMALLVECTOR_H |
14 | #define LLVM_ADT_SMALLVECTOR_H |
15 | |
16 | #include "llvm/ADT/iterator_range.h" |
17 | #include "llvm/Support/Compiler.h" |
18 | #include "llvm/Support/ErrorHandling.h" |
19 | #include "llvm/Support/MemAlloc.h" |
20 | #include "llvm/Support/type_traits.h" |
21 | #include <algorithm> |
22 | #include <cassert> |
23 | #include <cstddef> |
24 | #include <cstdlib> |
25 | #include <cstring> |
26 | #include <functional> |
27 | #include <initializer_list> |
28 | #include <iterator> |
29 | #include <limits> |
30 | #include <memory> |
31 | #include <new> |
32 | #include <type_traits> |
33 | #include <utility> |
34 | |
35 | namespace llvm { |
36 | |
37 | /// This is all the stuff common to all SmallVectors. |
38 | /// |
39 | /// The template parameter specifies the type which should be used to hold the |
40 | /// Size and Capacity of the SmallVector, so it can be adjusted. |
41 | /// Using 32 bit size is desirable to shrink the size of the SmallVector. |
42 | /// Using 64 bit size is desirable for cases like SmallVector<char>, where a |
43 | /// 32 bit size would limit the vector to ~4GB. SmallVectors are used for |
44 | /// buffering bitcode output - which can exceed 4GB. |
45 | template <class Size_T> class SmallVectorBase { |
46 | protected: |
47 | void *BeginX; |
48 | Size_T Size = 0, Capacity; |
49 | |
50 | /// The maximum value of the Size_T used. |
51 | static constexpr size_t SizeTypeMax() { |
52 | return std::numeric_limits<Size_T>::max(); |
53 | } |
54 | |
55 | SmallVectorBase() = delete; |
56 | SmallVectorBase(void *FirstEl, size_t TotalCapacity) |
57 | : BeginX(FirstEl), Capacity(TotalCapacity) {} |
58 | |
59 | /// This is a helper for \a grow() that's out of line to reduce code |
60 | /// duplication. This function will report a fatal error if it can't grow at |
61 | /// least to \p MinSize. |
62 | void *mallocForGrow(size_t MinSize, size_t TSize, size_t &NewCapacity); |
63 | |
64 | /// This is an implementation of the grow() method which only works |
65 | /// on POD-like data types and is out of line to reduce code duplication. |
66 | /// This function will report a fatal error if it cannot increase capacity. |
67 | void grow_pod(void *FirstEl, size_t MinSize, size_t TSize); |
68 | |
69 | public: |
70 | size_t size() const { return Size; } |
71 | size_t capacity() const { return Capacity; } |
72 | |
73 | LLVM_NODISCARD[[clang::warn_unused_result]] bool empty() const { return !Size; } |
74 | |
75 | /// Set the array size to \p N, which the current array must have enough |
76 | /// capacity for. |
77 | /// |
78 | /// This does not construct or destroy any elements in the vector. |
79 | /// |
80 | /// Clients can use this in conjunction with capacity() to write past the end |
81 | /// of the buffer when they know that more elements are available, and only |
82 | /// update the size later. This avoids the cost of value initializing elements |
83 | /// which will only be overwritten. |
84 | void set_size(size_t N) { |
85 | assert(N <= capacity())(static_cast<void> (0)); |
86 | Size = N; |
87 | } |
88 | }; |
89 | |
90 | template <class T> |
91 | using SmallVectorSizeType = |
92 | typename std::conditional<sizeof(T) < 4 && sizeof(void *) >= 8, uint64_t, |
93 | uint32_t>::type; |
94 | |
95 | /// Figure out the offset of the first element. |
96 | template <class T, typename = void> struct SmallVectorAlignmentAndSize { |
97 | alignas(SmallVectorBase<SmallVectorSizeType<T>>) char Base[sizeof( |
98 | SmallVectorBase<SmallVectorSizeType<T>>)]; |
99 | alignas(T) char FirstEl[sizeof(T)]; |
100 | }; |
101 | |
102 | /// This is the part of SmallVectorTemplateBase which does not depend on whether |
103 | /// the type T is a POD. The extra dummy template argument is used by ArrayRef |
104 | /// to avoid unnecessarily requiring T to be complete. |
105 | template <typename T, typename = void> |
106 | class SmallVectorTemplateCommon |
107 | : public SmallVectorBase<SmallVectorSizeType<T>> { |
108 | using Base = SmallVectorBase<SmallVectorSizeType<T>>; |
109 | |
110 | /// Find the address of the first element. For this pointer math to be valid |
111 | /// with small-size of 0 for T with lots of alignment, it's important that |
112 | /// SmallVectorStorage is properly-aligned even for small-size of 0. |
113 | void *getFirstEl() const { |
114 | return const_cast<void *>(reinterpret_cast<const void *>( |
115 | reinterpret_cast<const char *>(this) + |
116 | offsetof(SmallVectorAlignmentAndSize<T>, FirstEl)__builtin_offsetof(SmallVectorAlignmentAndSize<T>, FirstEl ))); |
117 | } |
118 | // Space after 'FirstEl' is clobbered, do not add any instance vars after it. |
119 | |
120 | protected: |
121 | SmallVectorTemplateCommon(size_t Size) : Base(getFirstEl(), Size) {} |
122 | |
123 | void grow_pod(size_t MinSize, size_t TSize) { |
124 | Base::grow_pod(getFirstEl(), MinSize, TSize); |
125 | } |
126 | |
127 | /// Return true if this is a smallvector which has not had dynamic |
128 | /// memory allocated for it. |
129 | bool isSmall() const { return this->BeginX == getFirstEl(); } |
130 | |
131 | /// Put this vector in a state of being small. |
132 | void resetToSmall() { |
133 | this->BeginX = getFirstEl(); |
134 | this->Size = this->Capacity = 0; // FIXME: Setting Capacity to 0 is suspect. |
135 | } |
136 | |
137 | /// Return true if V is an internal reference to the given range. |
138 | bool isReferenceToRange(const void *V, const void *First, const void *Last) const { |
139 | // Use std::less to avoid UB. |
140 | std::less<> LessThan; |
141 | return !LessThan(V, First) && LessThan(V, Last); |
142 | } |
143 | |
144 | /// Return true if V is an internal reference to this vector. |
145 | bool isReferenceToStorage(const void *V) const { |
146 | return isReferenceToRange(V, this->begin(), this->end()); |
147 | } |
148 | |
149 | /// Return true if First and Last form a valid (possibly empty) range in this |
150 | /// vector's storage. |
151 | bool isRangeInStorage(const void *First, const void *Last) const { |
152 | // Use std::less to avoid UB. |
153 | std::less<> LessThan; |
154 | return !LessThan(First, this->begin()) && !LessThan(Last, First) && |
155 | !LessThan(this->end(), Last); |
156 | } |
157 | |
158 | /// Return true unless Elt will be invalidated by resizing the vector to |
159 | /// NewSize. |
160 | bool isSafeToReferenceAfterResize(const void *Elt, size_t NewSize) { |
161 | // Past the end. |
162 | if (LLVM_LIKELY(!isReferenceToStorage(Elt))__builtin_expect((bool)(!isReferenceToStorage(Elt)), true)) |
163 | return true; |
164 | |
165 | // Return false if Elt will be destroyed by shrinking. |
166 | if (NewSize <= this->size()) |
167 | return Elt < this->begin() + NewSize; |
168 | |
169 | // Return false if we need to grow. |
170 | return NewSize <= this->capacity(); |
171 | } |
172 | |
173 | /// Check whether Elt will be invalidated by resizing the vector to NewSize. |
174 | void assertSafeToReferenceAfterResize(const void *Elt, size_t NewSize) { |
175 | assert(isSafeToReferenceAfterResize(Elt, NewSize) &&(static_cast<void> (0)) |
176 | "Attempting to reference an element of the vector in an operation "(static_cast<void> (0)) |
177 | "that invalidates it")(static_cast<void> (0)); |
178 | } |
179 | |
180 | /// Check whether Elt will be invalidated by increasing the size of the |
181 | /// vector by N. |
182 | void assertSafeToAdd(const void *Elt, size_t N = 1) { |
183 | this->assertSafeToReferenceAfterResize(Elt, this->size() + N); |
184 | } |
185 | |
186 | /// Check whether any part of the range will be invalidated by clearing. |
187 | void assertSafeToReferenceAfterClear(const T *From, const T *To) { |
188 | if (From == To) |
189 | return; |
190 | this->assertSafeToReferenceAfterResize(From, 0); |
191 | this->assertSafeToReferenceAfterResize(To - 1, 0); |
192 | } |
193 | template < |
194 | class ItTy, |
195 | std::enable_if_t<!std::is_same<std::remove_const_t<ItTy>, T *>::value, |
196 | bool> = false> |
197 | void assertSafeToReferenceAfterClear(ItTy, ItTy) {} |
198 | |
199 | /// Check whether any part of the range will be invalidated by growing. |
200 | void assertSafeToAddRange(const T *From, const T *To) { |
201 | if (From == To) |
202 | return; |
203 | this->assertSafeToAdd(From, To - From); |
204 | this->assertSafeToAdd(To - 1, To - From); |
205 | } |
206 | template < |
207 | class ItTy, |
208 | std::enable_if_t<!std::is_same<std::remove_const_t<ItTy>, T *>::value, |
209 | bool> = false> |
210 | void assertSafeToAddRange(ItTy, ItTy) {} |
211 | |
212 | /// Reserve enough space to add one element, and return the updated element |
213 | /// pointer in case it was a reference to the storage. |
214 | template <class U> |
215 | static const T *reserveForParamAndGetAddressImpl(U *This, const T &Elt, |
216 | size_t N) { |
217 | size_t NewSize = This->size() + N; |
218 | if (LLVM_LIKELY(NewSize <= This->capacity())__builtin_expect((bool)(NewSize <= This->capacity()), true )) |
219 | return &Elt; |
220 | |
221 | bool ReferencesStorage = false; |
222 | int64_t Index = -1; |
223 | if (!U::TakesParamByValue) { |
224 | if (LLVM_UNLIKELY(This->isReferenceToStorage(&Elt))__builtin_expect((bool)(This->isReferenceToStorage(&Elt )), false)) { |
225 | ReferencesStorage = true; |
226 | Index = &Elt - This->begin(); |
227 | } |
228 | } |
229 | This->grow(NewSize); |
230 | return ReferencesStorage ? This->begin() + Index : &Elt; |
231 | } |
232 | |
233 | public: |
234 | using size_type = size_t; |
235 | using difference_type = ptrdiff_t; |
236 | using value_type = T; |
237 | using iterator = T *; |
238 | using const_iterator = const T *; |
239 | |
240 | using const_reverse_iterator = std::reverse_iterator<const_iterator>; |
241 | using reverse_iterator = std::reverse_iterator<iterator>; |
242 | |
243 | using reference = T &; |
244 | using const_reference = const T &; |
245 | using pointer = T *; |
246 | using const_pointer = const T *; |
247 | |
248 | using Base::capacity; |
249 | using Base::empty; |
250 | using Base::size; |
251 | |
252 | // forward iterator creation methods. |
253 | iterator begin() { return (iterator)this->BeginX; } |
254 | const_iterator begin() const { return (const_iterator)this->BeginX; } |
255 | iterator end() { return begin() + size(); } |
256 | const_iterator end() const { return begin() + size(); } |
257 | |
258 | // reverse iterator creation methods. |
259 | reverse_iterator rbegin() { return reverse_iterator(end()); } |
260 | const_reverse_iterator rbegin() const{ return const_reverse_iterator(end()); } |
261 | reverse_iterator rend() { return reverse_iterator(begin()); } |
262 | const_reverse_iterator rend() const { return const_reverse_iterator(begin());} |
263 | |
264 | size_type size_in_bytes() const { return size() * sizeof(T); } |
265 | size_type max_size() const { |
266 | return std::min(this->SizeTypeMax(), size_type(-1) / sizeof(T)); |
267 | } |
268 | |
269 | size_t capacity_in_bytes() const { return capacity() * sizeof(T); } |
270 | |
271 | /// Return a pointer to the vector's buffer, even if empty(). |
272 | pointer data() { return pointer(begin()); } |
273 | /// Return a pointer to the vector's buffer, even if empty(). |
274 | const_pointer data() const { return const_pointer(begin()); } |
275 | |
276 | reference operator[](size_type idx) { |
277 | assert(idx < size())(static_cast<void> (0)); |
278 | return begin()[idx]; |
279 | } |
280 | const_reference operator[](size_type idx) const { |
281 | assert(idx < size())(static_cast<void> (0)); |
282 | return begin()[idx]; |
283 | } |
284 | |
285 | reference front() { |
286 | assert(!empty())(static_cast<void> (0)); |
287 | return begin()[0]; |
288 | } |
289 | const_reference front() const { |
290 | assert(!empty())(static_cast<void> (0)); |
291 | return begin()[0]; |
292 | } |
293 | |
294 | reference back() { |
295 | assert(!empty())(static_cast<void> (0)); |
296 | return end()[-1]; |
297 | } |
298 | const_reference back() const { |
299 | assert(!empty())(static_cast<void> (0)); |
300 | return end()[-1]; |
301 | } |
302 | }; |
303 | |
304 | /// SmallVectorTemplateBase<TriviallyCopyable = false> - This is where we put |
305 | /// method implementations that are designed to work with non-trivial T's. |
306 | /// |
307 | /// We approximate is_trivially_copyable with trivial move/copy construction and |
308 | /// trivial destruction. While the standard doesn't specify that you're allowed |
309 | /// copy these types with memcpy, there is no way for the type to observe this. |
310 | /// This catches the important case of std::pair<POD, POD>, which is not |
311 | /// trivially assignable. |
312 | template <typename T, bool = (is_trivially_copy_constructible<T>::value) && |
313 | (is_trivially_move_constructible<T>::value) && |
314 | std::is_trivially_destructible<T>::value> |
315 | class SmallVectorTemplateBase : public SmallVectorTemplateCommon<T> { |
316 | friend class SmallVectorTemplateCommon<T>; |
317 | |
318 | protected: |
319 | static constexpr bool TakesParamByValue = false; |
320 | using ValueParamT = const T &; |
321 | |
322 | SmallVectorTemplateBase(size_t Size) : SmallVectorTemplateCommon<T>(Size) {} |
323 | |
324 | static void destroy_range(T *S, T *E) { |
325 | while (S != E) { |
326 | --E; |
327 | E->~T(); |
328 | } |
329 | } |
330 | |
331 | /// Move the range [I, E) into the uninitialized memory starting with "Dest", |
332 | /// constructing elements as needed. |
333 | template<typename It1, typename It2> |
334 | static void uninitialized_move(It1 I, It1 E, It2 Dest) { |
335 | std::uninitialized_copy(std::make_move_iterator(I), |
336 | std::make_move_iterator(E), Dest); |
337 | } |
338 | |
339 | /// Copy the range [I, E) onto the uninitialized memory starting with "Dest", |
340 | /// constructing elements as needed. |
341 | template<typename It1, typename It2> |
342 | static void uninitialized_copy(It1 I, It1 E, It2 Dest) { |
343 | std::uninitialized_copy(I, E, Dest); |
344 | } |
345 | |
346 | /// Grow the allocated memory (without initializing new elements), doubling |
347 | /// the size of the allocated memory. Guarantees space for at least one more |
348 | /// element, or MinSize more elements if specified. |
349 | void grow(size_t MinSize = 0); |
350 | |
351 | /// Create a new allocation big enough for \p MinSize and pass back its size |
352 | /// in \p NewCapacity. This is the first section of \a grow(). |
353 | T *mallocForGrow(size_t MinSize, size_t &NewCapacity) { |
354 | return static_cast<T *>( |
355 | SmallVectorBase<SmallVectorSizeType<T>>::mallocForGrow( |
356 | MinSize, sizeof(T), NewCapacity)); |
357 | } |
358 | |
359 | /// Move existing elements over to the new allocation \p NewElts, the middle |
360 | /// section of \a grow(). |
361 | void moveElementsForGrow(T *NewElts); |
362 | |
363 | /// Transfer ownership of the allocation, finishing up \a grow(). |
364 | void takeAllocationForGrow(T *NewElts, size_t NewCapacity); |
365 | |
366 | /// Reserve enough space to add one element, and return the updated element |
367 | /// pointer in case it was a reference to the storage. |
368 | const T *reserveForParamAndGetAddress(const T &Elt, size_t N = 1) { |
369 | return this->reserveForParamAndGetAddressImpl(this, Elt, N); |
370 | } |
371 | |
372 | /// Reserve enough space to add one element, and return the updated element |
373 | /// pointer in case it was a reference to the storage. |
374 | T *reserveForParamAndGetAddress(T &Elt, size_t N = 1) { |
375 | return const_cast<T *>( |
376 | this->reserveForParamAndGetAddressImpl(this, Elt, N)); |
377 | } |
378 | |
379 | static T &&forward_value_param(T &&V) { return std::move(V); } |
380 | static const T &forward_value_param(const T &V) { return V; } |
381 | |
382 | void growAndAssign(size_t NumElts, const T &Elt) { |
383 | // Grow manually in case Elt is an internal reference. |
384 | size_t NewCapacity; |
385 | T *NewElts = mallocForGrow(NumElts, NewCapacity); |
386 | std::uninitialized_fill_n(NewElts, NumElts, Elt); |
387 | this->destroy_range(this->begin(), this->end()); |
388 | takeAllocationForGrow(NewElts, NewCapacity); |
389 | this->set_size(NumElts); |
390 | } |
391 | |
392 | template <typename... ArgTypes> T &growAndEmplaceBack(ArgTypes &&... Args) { |
393 | // Grow manually in case one of Args is an internal reference. |
394 | size_t NewCapacity; |
395 | T *NewElts = mallocForGrow(0, NewCapacity); |
396 | ::new ((void *)(NewElts + this->size())) T(std::forward<ArgTypes>(Args)...); |
397 | moveElementsForGrow(NewElts); |
398 | takeAllocationForGrow(NewElts, NewCapacity); |
399 | this->set_size(this->size() + 1); |
400 | return this->back(); |
401 | } |
402 | |
403 | public: |
404 | void push_back(const T &Elt) { |
405 | const T *EltPtr = reserveForParamAndGetAddress(Elt); |
406 | ::new ((void *)this->end()) T(*EltPtr); |
407 | this->set_size(this->size() + 1); |
408 | } |
409 | |
410 | void push_back(T &&Elt) { |
411 | T *EltPtr = reserveForParamAndGetAddress(Elt); |
412 | ::new ((void *)this->end()) T(::std::move(*EltPtr)); |
413 | this->set_size(this->size() + 1); |
414 | } |
415 | |
416 | void pop_back() { |
417 | this->set_size(this->size() - 1); |
418 | this->end()->~T(); |
419 | } |
420 | }; |
421 | |
422 | // Define this out-of-line to dissuade the C++ compiler from inlining it. |
423 | template <typename T, bool TriviallyCopyable> |
424 | void SmallVectorTemplateBase<T, TriviallyCopyable>::grow(size_t MinSize) { |
425 | size_t NewCapacity; |
426 | T *NewElts = mallocForGrow(MinSize, NewCapacity); |
427 | moveElementsForGrow(NewElts); |
428 | takeAllocationForGrow(NewElts, NewCapacity); |
429 | } |
430 | |
431 | // Define this out-of-line to dissuade the C++ compiler from inlining it. |
432 | template <typename T, bool TriviallyCopyable> |
433 | void SmallVectorTemplateBase<T, TriviallyCopyable>::moveElementsForGrow( |
434 | T *NewElts) { |
435 | // Move the elements over. |
436 | this->uninitialized_move(this->begin(), this->end(), NewElts); |
437 | |
438 | // Destroy the original elements. |
439 | destroy_range(this->begin(), this->end()); |
440 | } |
441 | |
442 | // Define this out-of-line to dissuade the C++ compiler from inlining it. |
443 | template <typename T, bool TriviallyCopyable> |
444 | void SmallVectorTemplateBase<T, TriviallyCopyable>::takeAllocationForGrow( |
445 | T *NewElts, size_t NewCapacity) { |
446 | // If this wasn't grown from the inline copy, deallocate the old space. |
447 | if (!this->isSmall()) |
448 | free(this->begin()); |
449 | |
450 | this->BeginX = NewElts; |
451 | this->Capacity = NewCapacity; |
452 | } |
453 | |
454 | /// SmallVectorTemplateBase<TriviallyCopyable = true> - This is where we put |
455 | /// method implementations that are designed to work with trivially copyable |
456 | /// T's. This allows using memcpy in place of copy/move construction and |
457 | /// skipping destruction. |
458 | template <typename T> |
459 | class SmallVectorTemplateBase<T, true> : public SmallVectorTemplateCommon<T> { |
460 | friend class SmallVectorTemplateCommon<T>; |
461 | |
462 | protected: |
463 | /// True if it's cheap enough to take parameters by value. Doing so avoids |
464 | /// overhead related to mitigations for reference invalidation. |
465 | static constexpr bool TakesParamByValue = sizeof(T) <= 2 * sizeof(void *); |
466 | |
467 | /// Either const T& or T, depending on whether it's cheap enough to take |
468 | /// parameters by value. |
469 | using ValueParamT = |
470 | typename std::conditional<TakesParamByValue, T, const T &>::type; |
471 | |
472 | SmallVectorTemplateBase(size_t Size) : SmallVectorTemplateCommon<T>(Size) {} |
473 | |
474 | // No need to do a destroy loop for POD's. |
475 | static void destroy_range(T *, T *) {} |
476 | |
477 | /// Move the range [I, E) onto the uninitialized memory |
478 | /// starting with "Dest", constructing elements into it as needed. |
479 | template<typename It1, typename It2> |
480 | static void uninitialized_move(It1 I, It1 E, It2 Dest) { |
481 | // Just do a copy. |
482 | uninitialized_copy(I, E, Dest); |
483 | } |
484 | |
485 | /// Copy the range [I, E) onto the uninitialized memory |
486 | /// starting with "Dest", constructing elements into it as needed. |
487 | template<typename It1, typename It2> |
488 | static void uninitialized_copy(It1 I, It1 E, It2 Dest) { |
489 | // Arbitrary iterator types; just use the basic implementation. |
490 | std::uninitialized_copy(I, E, Dest); |
491 | } |
492 | |
493 | /// Copy the range [I, E) onto the uninitialized memory |
494 | /// starting with "Dest", constructing elements into it as needed. |
495 | template <typename T1, typename T2> |
496 | static void uninitialized_copy( |
497 | T1 *I, T1 *E, T2 *Dest, |
498 | std::enable_if_t<std::is_same<typename std::remove_const<T1>::type, |
499 | T2>::value> * = nullptr) { |
500 | // Use memcpy for PODs iterated by pointers (which includes SmallVector |
501 | // iterators): std::uninitialized_copy optimizes to memmove, but we can |
502 | // use memcpy here. Note that I and E are iterators and thus might be |
503 | // invalid for memcpy if they are equal. |
504 | if (I != E) |
505 | memcpy(reinterpret_cast<void *>(Dest), I, (E - I) * sizeof(T)); |
506 | } |
507 | |
508 | /// Double the size of the allocated memory, guaranteeing space for at |
509 | /// least one more element or MinSize if specified. |
510 | void grow(size_t MinSize = 0) { this->grow_pod(MinSize, sizeof(T)); } |
511 | |
512 | /// Reserve enough space to add one element, and return the updated element |
513 | /// pointer in case it was a reference to the storage. |
514 | const T *reserveForParamAndGetAddress(const T &Elt, size_t N = 1) { |
515 | return this->reserveForParamAndGetAddressImpl(this, Elt, N); |
516 | } |
517 | |
518 | /// Reserve enough space to add one element, and return the updated element |
519 | /// pointer in case it was a reference to the storage. |
520 | T *reserveForParamAndGetAddress(T &Elt, size_t N = 1) { |
521 | return const_cast<T *>( |
522 | this->reserveForParamAndGetAddressImpl(this, Elt, N)); |
523 | } |
524 | |
525 | /// Copy \p V or return a reference, depending on \a ValueParamT. |
526 | static ValueParamT forward_value_param(ValueParamT V) { return V; } |
527 | |
528 | void growAndAssign(size_t NumElts, T Elt) { |
529 | // Elt has been copied in case it's an internal reference, side-stepping |
530 | // reference invalidation problems without losing the realloc optimization. |
531 | this->set_size(0); |
532 | this->grow(NumElts); |
533 | std::uninitialized_fill_n(this->begin(), NumElts, Elt); |
534 | this->set_size(NumElts); |
535 | } |
536 | |
537 | template <typename... ArgTypes> T &growAndEmplaceBack(ArgTypes &&... Args) { |
538 | // Use push_back with a copy in case Args has an internal reference, |
539 | // side-stepping reference invalidation problems without losing the realloc |
540 | // optimization. |
541 | push_back(T(std::forward<ArgTypes>(Args)...)); |
542 | return this->back(); |
543 | } |
544 | |
545 | public: |
546 | void push_back(ValueParamT Elt) { |
547 | const T *EltPtr = reserveForParamAndGetAddress(Elt); |
548 | memcpy(reinterpret_cast<void *>(this->end()), EltPtr, sizeof(T)); |
549 | this->set_size(this->size() + 1); |
550 | } |
551 | |
552 | void pop_back() { this->set_size(this->size() - 1); } |
553 | }; |
554 | |
555 | /// This class consists of common code factored out of the SmallVector class to |
556 | /// reduce code duplication based on the SmallVector 'N' template parameter. |
557 | template <typename T> |
558 | class SmallVectorImpl : public SmallVectorTemplateBase<T> { |
559 | using SuperClass = SmallVectorTemplateBase<T>; |
560 | |
561 | public: |
562 | using iterator = typename SuperClass::iterator; |
563 | using const_iterator = typename SuperClass::const_iterator; |
564 | using reference = typename SuperClass::reference; |
565 | using size_type = typename SuperClass::size_type; |
566 | |
567 | protected: |
568 | using SmallVectorTemplateBase<T>::TakesParamByValue; |
569 | using ValueParamT = typename SuperClass::ValueParamT; |
570 | |
571 | // Default ctor - Initialize to empty. |
572 | explicit SmallVectorImpl(unsigned N) |
573 | : SmallVectorTemplateBase<T>(N) {} |
574 | |
575 | public: |
576 | SmallVectorImpl(const SmallVectorImpl &) = delete; |
577 | |
578 | ~SmallVectorImpl() { |
579 | // Subclass has already destructed this vector's elements. |
580 | // If this wasn't grown from the inline copy, deallocate the old space. |
581 | if (!this->isSmall()) |
582 | free(this->begin()); |
583 | } |
584 | |
585 | void clear() { |
586 | this->destroy_range(this->begin(), this->end()); |
587 | this->Size = 0; |
588 | } |
589 | |
590 | private: |
591 | template <bool ForOverwrite> void resizeImpl(size_type N) { |
592 | if (N < this->size()) { |
593 | this->pop_back_n(this->size() - N); |
594 | } else if (N > this->size()) { |
595 | this->reserve(N); |
596 | for (auto I = this->end(), E = this->begin() + N; I != E; ++I) |
597 | if (ForOverwrite) |
598 | new (&*I) T; |
599 | else |
600 | new (&*I) T(); |
601 | this->set_size(N); |
602 | } |
603 | } |
604 | |
605 | public: |
606 | void resize(size_type N) { resizeImpl<false>(N); } |
607 | |
608 | /// Like resize, but \ref T is POD, the new values won't be initialized. |
609 | void resize_for_overwrite(size_type N) { resizeImpl<true>(N); } |
610 | |
611 | void resize(size_type N, ValueParamT NV) { |
612 | if (N == this->size()) |
613 | return; |
614 | |
615 | if (N < this->size()) { |
616 | this->pop_back_n(this->size() - N); |
617 | return; |
618 | } |
619 | |
620 | // N > this->size(). Defer to append. |
621 | this->append(N - this->size(), NV); |
622 | } |
623 | |
624 | void reserve(size_type N) { |
625 | if (this->capacity() < N) |
626 | this->grow(N); |
627 | } |
628 | |
629 | void pop_back_n(size_type NumItems) { |
630 | assert(this->size() >= NumItems)(static_cast<void> (0)); |
631 | this->destroy_range(this->end() - NumItems, this->end()); |
632 | this->set_size(this->size() - NumItems); |
633 | } |
634 | |
635 | LLVM_NODISCARD[[clang::warn_unused_result]] T pop_back_val() { |
636 | T Result = ::std::move(this->back()); |
637 | this->pop_back(); |
638 | return Result; |
639 | } |
640 | |
641 | void swap(SmallVectorImpl &RHS); |
642 | |
643 | /// Add the specified range to the end of the SmallVector. |
644 | template <typename in_iter, |
645 | typename = std::enable_if_t<std::is_convertible< |
646 | typename std::iterator_traits<in_iter>::iterator_category, |
647 | std::input_iterator_tag>::value>> |
648 | void append(in_iter in_start, in_iter in_end) { |
649 | this->assertSafeToAddRange(in_start, in_end); |
650 | size_type NumInputs = std::distance(in_start, in_end); |
651 | this->reserve(this->size() + NumInputs); |
652 | this->uninitialized_copy(in_start, in_end, this->end()); |
653 | this->set_size(this->size() + NumInputs); |
654 | } |
655 | |
656 | /// Append \p NumInputs copies of \p Elt to the end. |
657 | void append(size_type NumInputs, ValueParamT Elt) { |
658 | const T *EltPtr = this->reserveForParamAndGetAddress(Elt, NumInputs); |
659 | std::uninitialized_fill_n(this->end(), NumInputs, *EltPtr); |
660 | this->set_size(this->size() + NumInputs); |
661 | } |
662 | |
663 | void append(std::initializer_list<T> IL) { |
664 | append(IL.begin(), IL.end()); |
665 | } |
666 | |
667 | void append(const SmallVectorImpl &RHS) { append(RHS.begin(), RHS.end()); } |
668 | |
669 | void assign(size_type NumElts, ValueParamT Elt) { |
670 | // Note that Elt could be an internal reference. |
671 | if (NumElts > this->capacity()) { |
672 | this->growAndAssign(NumElts, Elt); |
673 | return; |
674 | } |
675 | |
676 | // Assign over existing elements. |
677 | std::fill_n(this->begin(), std::min(NumElts, this->size()), Elt); |
678 | if (NumElts > this->size()) |
679 | std::uninitialized_fill_n(this->end(), NumElts - this->size(), Elt); |
680 | else if (NumElts < this->size()) |
681 | this->destroy_range(this->begin() + NumElts, this->end()); |
682 | this->set_size(NumElts); |
683 | } |
684 | |
685 | // FIXME: Consider assigning over existing elements, rather than clearing & |
686 | // re-initializing them - for all assign(...) variants. |
687 | |
688 | template <typename in_iter, |
689 | typename = std::enable_if_t<std::is_convertible< |
690 | typename std::iterator_traits<in_iter>::iterator_category, |
691 | std::input_iterator_tag>::value>> |
692 | void assign(in_iter in_start, in_iter in_end) { |
693 | this->assertSafeToReferenceAfterClear(in_start, in_end); |
694 | clear(); |
695 | append(in_start, in_end); |
696 | } |
697 | |
698 | void assign(std::initializer_list<T> IL) { |
699 | clear(); |
700 | append(IL); |
701 | } |
702 | |
703 | void assign(const SmallVectorImpl &RHS) { assign(RHS.begin(), RHS.end()); } |
704 | |
705 | iterator erase(const_iterator CI) { |
706 | // Just cast away constness because this is a non-const member function. |
707 | iterator I = const_cast<iterator>(CI); |
708 | |
709 | assert(this->isReferenceToStorage(CI) && "Iterator to erase is out of bounds.")(static_cast<void> (0)); |
710 | |
711 | iterator N = I; |
712 | // Shift all elts down one. |
713 | std::move(I+1, this->end(), I); |
714 | // Drop the last elt. |
715 | this->pop_back(); |
716 | return(N); |
717 | } |
718 | |
719 | iterator erase(const_iterator CS, const_iterator CE) { |
720 | // Just cast away constness because this is a non-const member function. |
721 | iterator S = const_cast<iterator>(CS); |
722 | iterator E = const_cast<iterator>(CE); |
723 | |
724 | assert(this->isRangeInStorage(S, E) && "Range to erase is out of bounds.")(static_cast<void> (0)); |
725 | |
726 | iterator N = S; |
727 | // Shift all elts down. |
728 | iterator I = std::move(E, this->end(), S); |
729 | // Drop the last elts. |
730 | this->destroy_range(I, this->end()); |
731 | this->set_size(I - this->begin()); |
732 | return(N); |
733 | } |
734 | |
735 | private: |
736 | template <class ArgType> iterator insert_one_impl(iterator I, ArgType &&Elt) { |
737 | // Callers ensure that ArgType is derived from T. |
738 | static_assert( |
739 | std::is_same<std::remove_const_t<std::remove_reference_t<ArgType>>, |
740 | T>::value, |
741 | "ArgType must be derived from T!"); |
742 | |
743 | if (I == this->end()) { // Important special case for empty vector. |
744 | this->push_back(::std::forward<ArgType>(Elt)); |
745 | return this->end()-1; |
746 | } |
747 | |
748 | assert(this->isReferenceToStorage(I) && "Insertion iterator is out of bounds.")(static_cast<void> (0)); |
749 | |
750 | // Grow if necessary. |
751 | size_t Index = I - this->begin(); |
752 | std::remove_reference_t<ArgType> *EltPtr = |
753 | this->reserveForParamAndGetAddress(Elt); |
754 | I = this->begin() + Index; |
755 | |
756 | ::new ((void*) this->end()) T(::std::move(this->back())); |
757 | // Push everything else over. |
758 | std::move_backward(I, this->end()-1, this->end()); |
759 | this->set_size(this->size() + 1); |
760 | |
761 | // If we just moved the element we're inserting, be sure to update |
762 | // the reference (never happens if TakesParamByValue). |
763 | static_assert(!TakesParamByValue || std::is_same<ArgType, T>::value, |
764 | "ArgType must be 'T' when taking by value!"); |
765 | if (!TakesParamByValue && this->isReferenceToRange(EltPtr, I, this->end())) |
766 | ++EltPtr; |
767 | |
768 | *I = ::std::forward<ArgType>(*EltPtr); |
769 | return I; |
770 | } |
771 | |
772 | public: |
773 | iterator insert(iterator I, T &&Elt) { |
774 | return insert_one_impl(I, this->forward_value_param(std::move(Elt))); |
775 | } |
776 | |
777 | iterator insert(iterator I, const T &Elt) { |
778 | return insert_one_impl(I, this->forward_value_param(Elt)); |
779 | } |
780 | |
781 | iterator insert(iterator I, size_type NumToInsert, ValueParamT Elt) { |
782 | // Convert iterator to elt# to avoid invalidating iterator when we reserve() |
783 | size_t InsertElt = I - this->begin(); |
784 | |
785 | if (I == this->end()) { // Important special case for empty vector. |
786 | append(NumToInsert, Elt); |
787 | return this->begin()+InsertElt; |
788 | } |
789 | |
790 | assert(this->isReferenceToStorage(I) && "Insertion iterator is out of bounds.")(static_cast<void> (0)); |
791 | |
792 | // Ensure there is enough space, and get the (maybe updated) address of |
793 | // Elt. |
794 | const T *EltPtr = this->reserveForParamAndGetAddress(Elt, NumToInsert); |
795 | |
796 | // Uninvalidate the iterator. |
797 | I = this->begin()+InsertElt; |
798 | |
799 | // If there are more elements between the insertion point and the end of the |
800 | // range than there are being inserted, we can use a simple approach to |
801 | // insertion. Since we already reserved space, we know that this won't |
802 | // reallocate the vector. |
803 | if (size_t(this->end()-I) >= NumToInsert) { |
804 | T *OldEnd = this->end(); |
805 | append(std::move_iterator<iterator>(this->end() - NumToInsert), |
806 | std::move_iterator<iterator>(this->end())); |
807 | |
808 | // Copy the existing elements that get replaced. |
809 | std::move_backward(I, OldEnd-NumToInsert, OldEnd); |
810 | |
811 | // If we just moved the element we're inserting, be sure to update |
812 | // the reference (never happens if TakesParamByValue). |
813 | if (!TakesParamByValue && I <= EltPtr && EltPtr < this->end()) |
814 | EltPtr += NumToInsert; |
815 | |
816 | std::fill_n(I, NumToInsert, *EltPtr); |
817 | return I; |
818 | } |
819 | |
820 | // Otherwise, we're inserting more elements than exist already, and we're |
821 | // not inserting at the end. |
822 | |
823 | // Move over the elements that we're about to overwrite. |
824 | T *OldEnd = this->end(); |
825 | this->set_size(this->size() + NumToInsert); |
826 | size_t NumOverwritten = OldEnd-I; |
827 | this->uninitialized_move(I, OldEnd, this->end()-NumOverwritten); |
828 | |
829 | // If we just moved the element we're inserting, be sure to update |
830 | // the reference (never happens if TakesParamByValue). |
831 | if (!TakesParamByValue && I <= EltPtr && EltPtr < this->end()) |
832 | EltPtr += NumToInsert; |
833 | |
834 | // Replace the overwritten part. |
835 | std::fill_n(I, NumOverwritten, *EltPtr); |
836 | |
837 | // Insert the non-overwritten middle part. |
838 | std::uninitialized_fill_n(OldEnd, NumToInsert - NumOverwritten, *EltPtr); |
839 | return I; |
840 | } |
841 | |
842 | template <typename ItTy, |
843 | typename = std::enable_if_t<std::is_convertible< |
844 | typename std::iterator_traits<ItTy>::iterator_category, |
845 | std::input_iterator_tag>::value>> |
846 | iterator insert(iterator I, ItTy From, ItTy To) { |
847 | // Convert iterator to elt# to avoid invalidating iterator when we reserve() |
848 | size_t InsertElt = I - this->begin(); |
849 | |
850 | if (I == this->end()) { // Important special case for empty vector. |
851 | append(From, To); |
852 | return this->begin()+InsertElt; |
853 | } |
854 | |
855 | assert(this->isReferenceToStorage(I) && "Insertion iterator is out of bounds.")(static_cast<void> (0)); |
856 | |
857 | // Check that the reserve that follows doesn't invalidate the iterators. |
858 | this->assertSafeToAddRange(From, To); |
859 | |
860 | size_t NumToInsert = std::distance(From, To); |
861 | |
862 | // Ensure there is enough space. |
863 | reserve(this->size() + NumToInsert); |
864 | |
865 | // Uninvalidate the iterator. |
866 | I = this->begin()+InsertElt; |
867 | |
868 | // If there are more elements between the insertion point and the end of the |
869 | // range than there are being inserted, we can use a simple approach to |
870 | // insertion. Since we already reserved space, we know that this won't |
871 | // reallocate the vector. |
872 | if (size_t(this->end()-I) >= NumToInsert) { |
873 | T *OldEnd = this->end(); |
874 | append(std::move_iterator<iterator>(this->end() - NumToInsert), |
875 | std::move_iterator<iterator>(this->end())); |
876 | |
877 | // Copy the existing elements that get replaced. |
878 | std::move_backward(I, OldEnd-NumToInsert, OldEnd); |
879 | |
880 | std::copy(From, To, I); |
881 | return I; |
882 | } |
883 | |
884 | // Otherwise, we're inserting more elements than exist already, and we're |
885 | // not inserting at the end. |
886 | |
887 | // Move over the elements that we're about to overwrite. |
888 | T *OldEnd = this->end(); |
889 | this->set_size(this->size() + NumToInsert); |
890 | size_t NumOverwritten = OldEnd-I; |
891 | this->uninitialized_move(I, OldEnd, this->end()-NumOverwritten); |
892 | |
893 | // Replace the overwritten part. |
894 | for (T *J = I; NumOverwritten > 0; --NumOverwritten) { |
895 | *J = *From; |
896 | ++J; ++From; |
897 | } |
898 | |
899 | // Insert the non-overwritten middle part. |
900 | this->uninitialized_copy(From, To, OldEnd); |
901 | return I; |
902 | } |
903 | |
904 | void insert(iterator I, std::initializer_list<T> IL) { |
905 | insert(I, IL.begin(), IL.end()); |
906 | } |
907 | |
908 | template <typename... ArgTypes> reference emplace_back(ArgTypes &&... Args) { |
909 | if (LLVM_UNLIKELY(this->size() >= this->capacity())__builtin_expect((bool)(this->size() >= this->capacity ()), false)) |
910 | return this->growAndEmplaceBack(std::forward<ArgTypes>(Args)...); |
911 | |
912 | ::new ((void *)this->end()) T(std::forward<ArgTypes>(Args)...); |
913 | this->set_size(this->size() + 1); |
914 | return this->back(); |
915 | } |
916 | |
917 | SmallVectorImpl &operator=(const SmallVectorImpl &RHS); |
918 | |
919 | SmallVectorImpl &operator=(SmallVectorImpl &&RHS); |
920 | |
921 | bool operator==(const SmallVectorImpl &RHS) const { |
922 | if (this->size() != RHS.size()) return false; |
923 | return std::equal(this->begin(), this->end(), RHS.begin()); |
924 | } |
925 | bool operator!=(const SmallVectorImpl &RHS) const { |
926 | return !(*this == RHS); |
927 | } |
928 | |
929 | bool operator<(const SmallVectorImpl &RHS) const { |
930 | return std::lexicographical_compare(this->begin(), this->end(), |
931 | RHS.begin(), RHS.end()); |
932 | } |
933 | }; |
934 | |
935 | template <typename T> |
936 | void SmallVectorImpl<T>::swap(SmallVectorImpl<T> &RHS) { |
937 | if (this == &RHS) return; |
938 | |
939 | // We can only avoid copying elements if neither vector is small. |
940 | if (!this->isSmall() && !RHS.isSmall()) { |
941 | std::swap(this->BeginX, RHS.BeginX); |
942 | std::swap(this->Size, RHS.Size); |
943 | std::swap(this->Capacity, RHS.Capacity); |
944 | return; |
945 | } |
946 | this->reserve(RHS.size()); |
947 | RHS.reserve(this->size()); |
948 | |
949 | // Swap the shared elements. |
950 | size_t NumShared = this->size(); |
951 | if (NumShared > RHS.size()) NumShared = RHS.size(); |
952 | for (size_type i = 0; i != NumShared; ++i) |
953 | std::swap((*this)[i], RHS[i]); |
954 | |
955 | // Copy over the extra elts. |
956 | if (this->size() > RHS.size()) { |
957 | size_t EltDiff = this->size() - RHS.size(); |
958 | this->uninitialized_copy(this->begin()+NumShared, this->end(), RHS.end()); |
959 | RHS.set_size(RHS.size() + EltDiff); |
960 | this->destroy_range(this->begin()+NumShared, this->end()); |
961 | this->set_size(NumShared); |
962 | } else if (RHS.size() > this->size()) { |
963 | size_t EltDiff = RHS.size() - this->size(); |
964 | this->uninitialized_copy(RHS.begin()+NumShared, RHS.end(), this->end()); |
965 | this->set_size(this->size() + EltDiff); |
966 | this->destroy_range(RHS.begin()+NumShared, RHS.end()); |
967 | RHS.set_size(NumShared); |
968 | } |
969 | } |
970 | |
971 | template <typename T> |
972 | SmallVectorImpl<T> &SmallVectorImpl<T>:: |
973 | operator=(const SmallVectorImpl<T> &RHS) { |
974 | // Avoid self-assignment. |
975 | if (this == &RHS) return *this; |
976 | |
977 | // If we already have sufficient space, assign the common elements, then |
978 | // destroy any excess. |
979 | size_t RHSSize = RHS.size(); |
980 | size_t CurSize = this->size(); |
981 | if (CurSize >= RHSSize) { |
982 | // Assign common elements. |
983 | iterator NewEnd; |
984 | if (RHSSize) |
985 | NewEnd = std::copy(RHS.begin(), RHS.begin()+RHSSize, this->begin()); |
986 | else |
987 | NewEnd = this->begin(); |
988 | |
989 | // Destroy excess elements. |
990 | this->destroy_range(NewEnd, this->end()); |
991 | |
992 | // Trim. |
993 | this->set_size(RHSSize); |
994 | return *this; |
995 | } |
996 | |
997 | // If we have to grow to have enough elements, destroy the current elements. |
998 | // This allows us to avoid copying them during the grow. |
999 | // FIXME: don't do this if they're efficiently moveable. |
1000 | if (this->capacity() < RHSSize) { |
1001 | // Destroy current elements. |
1002 | this->clear(); |
1003 | CurSize = 0; |
1004 | this->grow(RHSSize); |
1005 | } else if (CurSize) { |
1006 | // Otherwise, use assignment for the already-constructed elements. |
1007 | std::copy(RHS.begin(), RHS.begin()+CurSize, this->begin()); |
1008 | } |
1009 | |
1010 | // Copy construct the new elements in place. |
1011 | this->uninitialized_copy(RHS.begin()+CurSize, RHS.end(), |
1012 | this->begin()+CurSize); |
1013 | |
1014 | // Set end. |
1015 | this->set_size(RHSSize); |
1016 | return *this; |
1017 | } |
1018 | |
1019 | template <typename T> |
1020 | SmallVectorImpl<T> &SmallVectorImpl<T>::operator=(SmallVectorImpl<T> &&RHS) { |
1021 | // Avoid self-assignment. |
1022 | if (this == &RHS) return *this; |
1023 | |
1024 | // If the RHS isn't small, clear this vector and then steal its buffer. |
1025 | if (!RHS.isSmall()) { |
1026 | this->destroy_range(this->begin(), this->end()); |
1027 | if (!this->isSmall()) free(this->begin()); |
1028 | this->BeginX = RHS.BeginX; |
1029 | this->Size = RHS.Size; |
1030 | this->Capacity = RHS.Capacity; |
1031 | RHS.resetToSmall(); |
1032 | return *this; |
1033 | } |
1034 | |
1035 | // If we already have sufficient space, assign the common elements, then |
1036 | // destroy any excess. |
1037 | size_t RHSSize = RHS.size(); |
1038 | size_t CurSize = this->size(); |
1039 | if (CurSize >= RHSSize) { |
1040 | // Assign common elements. |
1041 | iterator NewEnd = this->begin(); |
1042 | if (RHSSize) |
1043 | NewEnd = std::move(RHS.begin(), RHS.end(), NewEnd); |
1044 | |
1045 | // Destroy excess elements and trim the bounds. |
1046 | this->destroy_range(NewEnd, this->end()); |
1047 | this->set_size(RHSSize); |
1048 | |
1049 | // Clear the RHS. |
1050 | RHS.clear(); |
1051 | |
1052 | return *this; |
1053 | } |
1054 | |
1055 | // If we have to grow to have enough elements, destroy the current elements. |
1056 | // This allows us to avoid copying them during the grow. |
1057 | // FIXME: this may not actually make any sense if we can efficiently move |
1058 | // elements. |
1059 | if (this->capacity() < RHSSize) { |
1060 | // Destroy current elements. |
1061 | this->clear(); |
1062 | CurSize = 0; |
1063 | this->grow(RHSSize); |
1064 | } else if (CurSize) { |
1065 | // Otherwise, use assignment for the already-constructed elements. |
1066 | std::move(RHS.begin(), RHS.begin()+CurSize, this->begin()); |
1067 | } |
1068 | |
1069 | // Move-construct the new elements in place. |
1070 | this->uninitialized_move(RHS.begin()+CurSize, RHS.end(), |
1071 | this->begin()+CurSize); |
1072 | |
1073 | // Set end. |
1074 | this->set_size(RHSSize); |
1075 | |
1076 | RHS.clear(); |
1077 | return *this; |
1078 | } |
1079 | |
1080 | /// Storage for the SmallVector elements. This is specialized for the N=0 case |
1081 | /// to avoid allocating unnecessary storage. |
1082 | template <typename T, unsigned N> |
1083 | struct SmallVectorStorage { |
1084 | alignas(T) char InlineElts[N * sizeof(T)]; |
1085 | }; |
1086 | |
1087 | /// We need the storage to be properly aligned even for small-size of 0 so that |
1088 | /// the pointer math in \a SmallVectorTemplateCommon::getFirstEl() is |
1089 | /// well-defined. |
1090 | template <typename T> struct alignas(T) SmallVectorStorage<T, 0> {}; |
1091 | |
1092 | /// Forward declaration of SmallVector so that |
1093 | /// calculateSmallVectorDefaultInlinedElements can reference |
1094 | /// `sizeof(SmallVector<T, 0>)`. |
1095 | template <typename T, unsigned N> class LLVM_GSL_OWNER[[gsl::Owner]] SmallVector; |
1096 | |
1097 | /// Helper class for calculating the default number of inline elements for |
1098 | /// `SmallVector<T>`. |
1099 | /// |
1100 | /// This should be migrated to a constexpr function when our minimum |
1101 | /// compiler support is enough for multi-statement constexpr functions. |
1102 | template <typename T> struct CalculateSmallVectorDefaultInlinedElements { |
1103 | // Parameter controlling the default number of inlined elements |
1104 | // for `SmallVector<T>`. |
1105 | // |
1106 | // The default number of inlined elements ensures that |
1107 | // 1. There is at least one inlined element. |
1108 | // 2. `sizeof(SmallVector<T>) <= kPreferredSmallVectorSizeof` unless |
1109 | // it contradicts 1. |
1110 | static constexpr size_t kPreferredSmallVectorSizeof = 64; |
1111 | |
1112 | // static_assert that sizeof(T) is not "too big". |
1113 | // |
1114 | // Because our policy guarantees at least one inlined element, it is possible |
1115 | // for an arbitrarily large inlined element to allocate an arbitrarily large |
1116 | // amount of inline storage. We generally consider it an antipattern for a |
1117 | // SmallVector to allocate an excessive amount of inline storage, so we want |
1118 | // to call attention to these cases and make sure that users are making an |
1119 | // intentional decision if they request a lot of inline storage. |
1120 | // |
1121 | // We want this assertion to trigger in pathological cases, but otherwise |
1122 | // not be too easy to hit. To accomplish that, the cutoff is actually somewhat |
1123 | // larger than kPreferredSmallVectorSizeof (otherwise, |
1124 | // `SmallVector<SmallVector<T>>` would be one easy way to trip it, and that |
1125 | // pattern seems useful in practice). |
1126 | // |
1127 | // One wrinkle is that this assertion is in theory non-portable, since |
1128 | // sizeof(T) is in general platform-dependent. However, we don't expect this |
1129 | // to be much of an issue, because most LLVM development happens on 64-bit |
1130 | // hosts, and therefore sizeof(T) is expected to *decrease* when compiled for |
1131 | // 32-bit hosts, dodging the issue. The reverse situation, where development |
1132 | // happens on a 32-bit host and then fails due to sizeof(T) *increasing* on a |
1133 | // 64-bit host, is expected to be very rare. |
1134 | static_assert( |
1135 | sizeof(T) <= 256, |
1136 | "You are trying to use a default number of inlined elements for " |
1137 | "`SmallVector<T>` but `sizeof(T)` is really big! Please use an " |
1138 | "explicit number of inlined elements with `SmallVector<T, N>` to make " |
1139 | "sure you really want that much inline storage."); |
1140 | |
1141 | // Discount the size of the header itself when calculating the maximum inline |
1142 | // bytes. |
1143 | static constexpr size_t PreferredInlineBytes = |
1144 | kPreferredSmallVectorSizeof - sizeof(SmallVector<T, 0>); |
1145 | static constexpr size_t NumElementsThatFit = PreferredInlineBytes / sizeof(T); |
1146 | static constexpr size_t value = |
1147 | NumElementsThatFit == 0 ? 1 : NumElementsThatFit; |
1148 | }; |
1149 | |
1150 | /// This is a 'vector' (really, a variable-sized array), optimized |
1151 | /// for the case when the array is small. It contains some number of elements |
1152 | /// in-place, which allows it to avoid heap allocation when the actual number of |
1153 | /// elements is below that threshold. This allows normal "small" cases to be |
1154 | /// fast without losing generality for large inputs. |
1155 | /// |
1156 | /// \note |
1157 | /// In the absence of a well-motivated choice for the number of inlined |
1158 | /// elements \p N, it is recommended to use \c SmallVector<T> (that is, |
1159 | /// omitting the \p N). This will choose a default number of inlined elements |
1160 | /// reasonable for allocation on the stack (for example, trying to keep \c |
1161 | /// sizeof(SmallVector<T>) around 64 bytes). |
1162 | /// |
1163 | /// \warning This does not attempt to be exception safe. |
1164 | /// |
1165 | /// \see https://llvm.org/docs/ProgrammersManual.html#llvm-adt-smallvector-h |
1166 | template <typename T, |
1167 | unsigned N = CalculateSmallVectorDefaultInlinedElements<T>::value> |
1168 | class LLVM_GSL_OWNER[[gsl::Owner]] SmallVector : public SmallVectorImpl<T>, |
1169 | SmallVectorStorage<T, N> { |
1170 | public: |
1171 | SmallVector() : SmallVectorImpl<T>(N) {} |
1172 | |
1173 | ~SmallVector() { |
1174 | // Destroy the constructed elements in the vector. |
1175 | this->destroy_range(this->begin(), this->end()); |
1176 | } |
1177 | |
1178 | explicit SmallVector(size_t Size, const T &Value = T()) |
1179 | : SmallVectorImpl<T>(N) { |
1180 | this->assign(Size, Value); |
1181 | } |
1182 | |
1183 | template <typename ItTy, |
1184 | typename = std::enable_if_t<std::is_convertible< |
1185 | typename std::iterator_traits<ItTy>::iterator_category, |
1186 | std::input_iterator_tag>::value>> |
1187 | SmallVector(ItTy S, ItTy E) : SmallVectorImpl<T>(N) { |
1188 | this->append(S, E); |
1189 | } |
1190 | |
1191 | template <typename RangeTy> |
1192 | explicit SmallVector(const iterator_range<RangeTy> &R) |
1193 | : SmallVectorImpl<T>(N) { |
1194 | this->append(R.begin(), R.end()); |
1195 | } |
1196 | |
1197 | SmallVector(std::initializer_list<T> IL) : SmallVectorImpl<T>(N) { |
1198 | this->assign(IL); |
1199 | } |
1200 | |
1201 | SmallVector(const SmallVector &RHS) : SmallVectorImpl<T>(N) { |
1202 | if (!RHS.empty()) |
1203 | SmallVectorImpl<T>::operator=(RHS); |
1204 | } |
1205 | |
1206 | SmallVector &operator=(const SmallVector &RHS) { |
1207 | SmallVectorImpl<T>::operator=(RHS); |
1208 | return *this; |
1209 | } |
1210 | |
1211 | SmallVector(SmallVector &&RHS) : SmallVectorImpl<T>(N) { |
1212 | if (!RHS.empty()) |
1213 | SmallVectorImpl<T>::operator=(::std::move(RHS)); |
1214 | } |
1215 | |
1216 | SmallVector(SmallVectorImpl<T> &&RHS) : SmallVectorImpl<T>(N) { |
1217 | if (!RHS.empty()) |
1218 | SmallVectorImpl<T>::operator=(::std::move(RHS)); |
1219 | } |
1220 | |
1221 | SmallVector &operator=(SmallVector &&RHS) { |
1222 | SmallVectorImpl<T>::operator=(::std::move(RHS)); |
1223 | return *this; |
1224 | } |
1225 | |
1226 | SmallVector &operator=(SmallVectorImpl<T> &&RHS) { |
1227 | SmallVectorImpl<T>::operator=(::std::move(RHS)); |
1228 | return *this; |
1229 | } |
1230 | |
1231 | SmallVector &operator=(std::initializer_list<T> IL) { |
1232 | this->assign(IL); |
1233 | return *this; |
1234 | } |
1235 | }; |
1236 | |
1237 | template <typename T, unsigned N> |
1238 | inline size_t capacity_in_bytes(const SmallVector<T, N> &X) { |
1239 | return X.capacity_in_bytes(); |
1240 | } |
1241 | |
1242 | /// Given a range of type R, iterate the entire range and return a |
1243 | /// SmallVector with elements of the vector. This is useful, for example, |
1244 | /// when you want to iterate a range and then sort the results. |
1245 | template <unsigned Size, typename R> |
1246 | SmallVector<typename std::remove_const<typename std::remove_reference< |
1247 | decltype(*std::begin(std::declval<R &>()))>::type>::type, |
1248 | Size> |
1249 | to_vector(R &&Range) { |
1250 | return {std::begin(Range), std::end(Range)}; |
1251 | } |
1252 | |
1253 | } // end namespace llvm |
1254 | |
1255 | namespace std { |
1256 | |
1257 | /// Implement std::swap in terms of SmallVector swap. |
1258 | template<typename T> |
1259 | inline void |
1260 | swap(llvm::SmallVectorImpl<T> &LHS, llvm::SmallVectorImpl<T> &RHS) { |
1261 | LHS.swap(RHS); |
1262 | } |
1263 | |
1264 | /// Implement std::swap in terms of SmallVector swap. |
1265 | template<typename T, unsigned N> |
1266 | inline void |
1267 | swap(llvm::SmallVector<T, N> &LHS, llvm::SmallVector<T, N> &RHS) { |
1268 | LHS.swap(RHS); |
1269 | } |
1270 | |
1271 | } // end namespace std |
1272 | |
1273 | #endif // LLVM_ADT_SMALLVECTOR_H |