diff options
Diffstat (limited to 'lib/Transforms/Scalar/NewGVN.cpp')
| -rw-r--r-- | lib/Transforms/Scalar/NewGVN.cpp | 210 |
1 files changed, 124 insertions, 86 deletions
diff --git a/lib/Transforms/Scalar/NewGVN.cpp b/lib/Transforms/Scalar/NewGVN.cpp index 3c9850b156ac..5e0a705782ea 100644 --- a/lib/Transforms/Scalar/NewGVN.cpp +++ b/lib/Transforms/Scalar/NewGVN.cpp @@ -283,7 +283,6 @@ public: // Forward propagation info const Expression *getDefiningExpr() const { return DefiningExpr; } - void setDefiningExpr(const Expression *E) { DefiningExpr = E; } // Value member set bool empty() const { return Members.empty(); } @@ -317,6 +316,9 @@ public: --StoreCount; } + // True if this class has no memory members. + bool definesNoMemory() const { return StoreCount == 0 && memory_empty(); } + // Return true if two congruence classes are equivalent to each other. This // means // that every field but the ID number and the dead field are equivalent. @@ -401,9 +403,12 @@ class NewGVN { MemorySSAWalker *MSSAWalker; const DataLayout &DL; std::unique_ptr<PredicateInfo> PredInfo; - BumpPtrAllocator ExpressionAllocator; - ArrayRecycler<Value *> ArgRecycler; - TarjanSCC SCCFinder; + + // These are the only two things the create* functions should have + // side-effects on due to allocating memory. + mutable BumpPtrAllocator ExpressionAllocator; + mutable ArrayRecycler<Value *> ArgRecycler; + mutable TarjanSCC SCCFinder; const SimplifyQuery SQ; // Number of function arguments, used by ranking @@ -430,11 +435,12 @@ class NewGVN { // In order to correctly ensure propagation, we must keep track of what // comparisons we used, so that when the values of the comparisons change, we // propagate the information to the places we used the comparison. - DenseMap<const Value *, SmallPtrSet<Instruction *, 2>> PredicateToUsers; - // Mapping from MemoryAccess we used to the MemoryAccess we used it with. Has + mutable DenseMap<const Value *, SmallPtrSet<Instruction *, 2>> + PredicateToUsers; // the same reasoning as PredicateToUsers. When we skip MemoryAccesses for // stores, we no longer can rely solely on the def-use chains of MemorySSA. - DenseMap<const MemoryAccess *, SmallPtrSet<MemoryAccess *, 2>> MemoryToUsers; + mutable DenseMap<const MemoryAccess *, SmallPtrSet<MemoryAccess *, 2>> + MemoryToUsers; // A table storing which memorydefs/phis represent a memory state provably // equivalent to another memory state. @@ -457,7 +463,7 @@ class NewGVN { DenseMap<const MemoryPhi *, MemoryPhiState> MemoryPhiState; enum PhiCycleState { PCS_Unknown, PCS_CycleFree, PCS_Cycle }; - DenseMap<const PHINode *, PhiCycleState> PhiCycleState; + mutable DenseMap<const PHINode *, PhiCycleState> PhiCycleState; // Expression to class mapping. using ExpressionClassMap = DenseMap<const Expression *, CongruenceClass *>; ExpressionClassMap ExpressionToClass; @@ -511,21 +517,24 @@ public: private: // Expression handling. - const Expression *createExpression(Instruction *); - const Expression *createBinaryExpression(unsigned, Type *, Value *, Value *); - PHIExpression *createPHIExpression(Instruction *, bool &HasBackedge, - bool &AllConstant); - const VariableExpression *createVariableExpression(Value *); - const ConstantExpression *createConstantExpression(Constant *); - const Expression *createVariableOrConstant(Value *V); - const UnknownExpression *createUnknownExpression(Instruction *); + const Expression *createExpression(Instruction *) const; + const Expression *createBinaryExpression(unsigned, Type *, Value *, + Value *) const; + PHIExpression *createPHIExpression(Instruction *, bool &HasBackEdge, + bool &AllConstant) const; + const VariableExpression *createVariableExpression(Value *) const; + const ConstantExpression *createConstantExpression(Constant *) const; + const Expression *createVariableOrConstant(Value *V) const; + const UnknownExpression *createUnknownExpression(Instruction *) const; const StoreExpression *createStoreExpression(StoreInst *, - const MemoryAccess *); + const MemoryAccess *) const; LoadExpression *createLoadExpression(Type *, Value *, LoadInst *, - const MemoryAccess *); - const CallExpression *createCallExpression(CallInst *, const MemoryAccess *); - const AggregateValueExpression *createAggregateValueExpression(Instruction *); - bool setBasicExpressionInfo(Instruction *, BasicExpression *); + const MemoryAccess *) const; + const CallExpression *createCallExpression(CallInst *, + const MemoryAccess *) const; + const AggregateValueExpression * + createAggregateValueExpression(Instruction *) const; + bool setBasicExpressionInfo(Instruction *, BasicExpression *) const; // Congruence class handling. CongruenceClass *createCongruenceClass(Value *Leader, const Expression *E) { @@ -560,17 +569,18 @@ private: // Symbolic evaluation. const Expression *checkSimplificationResults(Expression *, Instruction *, - Value *); - const Expression *performSymbolicEvaluation(Value *); + Value *) const; + const Expression *performSymbolicEvaluation(Value *) const; const Expression *performSymbolicLoadCoercion(Type *, Value *, LoadInst *, - Instruction *, MemoryAccess *); - const Expression *performSymbolicLoadEvaluation(Instruction *); - const Expression *performSymbolicStoreEvaluation(Instruction *); - const Expression *performSymbolicCallEvaluation(Instruction *); - const Expression *performSymbolicPHIEvaluation(Instruction *); - const Expression *performSymbolicAggrValueEvaluation(Instruction *); - const Expression *performSymbolicCmpEvaluation(Instruction *); - const Expression *performSymbolicPredicateInfoEvaluation(Instruction *); + Instruction *, + MemoryAccess *) const; + const Expression *performSymbolicLoadEvaluation(Instruction *) const; + const Expression *performSymbolicStoreEvaluation(Instruction *) const; + const Expression *performSymbolicCallEvaluation(Instruction *) const; + const Expression *performSymbolicPHIEvaluation(Instruction *) const; + const Expression *performSymbolicAggrValueEvaluation(Instruction *) const; + const Expression *performSymbolicCmpEvaluation(Instruction *) const; + const Expression *performSymbolicPredicateInfoEvaluation(Instruction *) const; // Congruence finding. bool someEquivalentDominates(const Instruction *, const Instruction *) const; @@ -620,8 +630,8 @@ private: void markPredicateUsersTouched(Instruction *); void markValueLeaderChangeTouched(CongruenceClass *CC); void markMemoryLeaderChangeTouched(CongruenceClass *CC); - void addPredicateUsers(const PredicateBase *, Instruction *); - void addMemoryUsers(const MemoryAccess *To, MemoryAccess *U); + void addPredicateUsers(const PredicateBase *, Instruction *) const; + void addMemoryUsers(const MemoryAccess *To, MemoryAccess *U) const; // Main loop of value numbering void iterateTouchedInstructions(); @@ -634,7 +644,7 @@ private: void verifyIterationSettled(Function &F); bool singleReachablePHIPath(const MemoryAccess *, const MemoryAccess *) const; BasicBlock *getBlockForValue(Value *V) const; - void deleteExpression(const Expression *E); + void deleteExpression(const Expression *E) const; unsigned InstrToDFSNum(const Value *V) const { assert(isa<Instruction>(V) && "This should not be used for MemoryAccesses"); return InstrDFS.lookup(V); @@ -654,7 +664,7 @@ private: ? InstrToDFSNum(cast<MemoryUseOrDef>(MA)->getMemoryInst()) : InstrDFS.lookup(MA); } - bool isCycleFree(const PHINode *PN); + bool isCycleFree(const PHINode *PN) const; template <class T, class Range> T *getMinDFSOfRange(const Range &) const; // Debug counter info. When verifying, we have to reset the value numbering // debug counter to the same state it started in to get the same results. @@ -702,7 +712,7 @@ BasicBlock *NewGVN::getBlockForValue(Value *V) const { // Delete a definitely dead expression, so it can be reused by the expression // allocator. Some of these are not in creation functions, so we have to accept // const versions. -void NewGVN::deleteExpression(const Expression *E) { +void NewGVN::deleteExpression(const Expression *E) const { assert(isa<BasicExpression>(E)); auto *BE = cast<BasicExpression>(E); const_cast<BasicExpression *>(BE)->deallocateOperands(ArgRecycler); @@ -710,7 +720,7 @@ void NewGVN::deleteExpression(const Expression *E) { } PHIExpression *NewGVN::createPHIExpression(Instruction *I, bool &HasBackedge, - bool &AllConstant) { + bool &AllConstant) const { BasicBlock *PHIBlock = I->getParent(); auto *PN = cast<PHINode>(I); auto *E = @@ -722,30 +732,46 @@ PHIExpression *NewGVN::createPHIExpression(Instruction *I, bool &HasBackedge, unsigned PHIRPO = RPOOrdering.lookup(DT->getNode(PHIBlock)); + // NewGVN assumes the operands of a PHI node are in a consistent order across + // PHIs. LLVM doesn't seem to always guarantee this. While we need to fix + // this in LLVM at some point we don't want GVN to find wrong congruences. + // Therefore, here we sort uses in predecessor order. + // We're sorting the values by pointer. In theory this might be cause of + // non-determinism, but here we don't rely on the ordering for anything + // significant, e.g. we don't create new instructions based on it so we're + // fine. + SmallVector<const Use *, 4> PHIOperands; + for (const Use &U : PN->operands()) + PHIOperands.push_back(&U); + std::sort(PHIOperands.begin(), PHIOperands.end(), + [&](const Use *U1, const Use *U2) { + return PN->getIncomingBlock(*U1) < PN->getIncomingBlock(*U2); + }); + // Filter out unreachable phi operands. - auto Filtered = make_filter_range(PN->operands(), [&](const Use &U) { - return ReachableEdges.count({PN->getIncomingBlock(U), PHIBlock}); + auto Filtered = make_filter_range(PHIOperands, [&](const Use *U) { + return ReachableEdges.count({PN->getIncomingBlock(*U), PHIBlock}); }); std::transform(Filtered.begin(), Filtered.end(), op_inserter(E), - [&](const Use &U) -> Value * { - auto *BB = PN->getIncomingBlock(U); + [&](const Use *U) -> Value * { + auto *BB = PN->getIncomingBlock(*U); auto *DTN = DT->getNode(BB); if (RPOOrdering.lookup(DTN) >= PHIRPO) HasBackedge = true; - AllConstant &= isa<UndefValue>(U) || isa<Constant>(U); + AllConstant &= isa<UndefValue>(*U) || isa<Constant>(*U); // Don't try to transform self-defined phis. - if (U == PN) + if (*U == PN) return PN; - return lookupOperandLeader(U); + return lookupOperandLeader(*U); }); return E; } // Set basic expression info (Arguments, type, opcode) for Expression // E from Instruction I in block B. -bool NewGVN::setBasicExpressionInfo(Instruction *I, BasicExpression *E) { +bool NewGVN::setBasicExpressionInfo(Instruction *I, BasicExpression *E) const { bool AllConstant = true; if (auto *GEP = dyn_cast<GetElementPtrInst>(I)) E->setType(GEP->getSourceElementType()); @@ -766,7 +792,8 @@ bool NewGVN::setBasicExpressionInfo(Instruction *I, BasicExpression *E) { } const Expression *NewGVN::createBinaryExpression(unsigned Opcode, Type *T, - Value *Arg1, Value *Arg2) { + Value *Arg1, + Value *Arg2) const { auto *E = new (ExpressionAllocator) BasicExpression(2); E->setType(T); @@ -795,7 +822,8 @@ const Expression *NewGVN::createBinaryExpression(unsigned Opcode, Type *T, // TODO: Once finished, this should not take an Instruction, we only // use it for printing. const Expression *NewGVN::checkSimplificationResults(Expression *E, - Instruction *I, Value *V) { + Instruction *I, + Value *V) const { if (!V) return nullptr; if (auto *C = dyn_cast<Constant>(V)) { @@ -827,7 +855,7 @@ const Expression *NewGVN::checkSimplificationResults(Expression *E, return nullptr; } -const Expression *NewGVN::createExpression(Instruction *I) { +const Expression *NewGVN::createExpression(Instruction *I) const { auto *E = new (ExpressionAllocator) BasicExpression(I->getNumOperands()); bool AllConstant = setBasicExpressionInfo(I, E); @@ -913,7 +941,7 @@ const Expression *NewGVN::createExpression(Instruction *I) { } const AggregateValueExpression * -NewGVN::createAggregateValueExpression(Instruction *I) { +NewGVN::createAggregateValueExpression(Instruction *I) const { if (auto *II = dyn_cast<InsertValueInst>(I)) { auto *E = new (ExpressionAllocator) AggregateValueExpression(I->getNumOperands(), II->getNumIndices()); @@ -932,32 +960,32 @@ NewGVN::createAggregateValueExpression(Instruction *I) { llvm_unreachable("Unhandled type of aggregate value operation"); } -const VariableExpression *NewGVN::createVariableExpression(Value *V) { +const VariableExpression *NewGVN::createVariableExpression(Value *V) const { auto *E = new (ExpressionAllocator) VariableExpression(V); E->setOpcode(V->getValueID()); return E; } -const Expression *NewGVN::createVariableOrConstant(Value *V) { +const Expression *NewGVN::createVariableOrConstant(Value *V) const { if (auto *C = dyn_cast<Constant>(V)) return createConstantExpression(C); return createVariableExpression(V); } -const ConstantExpression *NewGVN::createConstantExpression(Constant *C) { +const ConstantExpression *NewGVN::createConstantExpression(Constant *C) const { auto *E = new (ExpressionAllocator) ConstantExpression(C); E->setOpcode(C->getValueID()); return E; } -const UnknownExpression *NewGVN::createUnknownExpression(Instruction *I) { +const UnknownExpression *NewGVN::createUnknownExpression(Instruction *I) const { auto *E = new (ExpressionAllocator) UnknownExpression(I); E->setOpcode(I->getOpcode()); return E; } -const CallExpression *NewGVN::createCallExpression(CallInst *CI, - const MemoryAccess *MA) { +const CallExpression * +NewGVN::createCallExpression(CallInst *CI, const MemoryAccess *MA) const { // FIXME: Add operand bundles for calls. auto *E = new (ExpressionAllocator) CallExpression(CI->getNumOperands(), CI, MA); @@ -1017,9 +1045,8 @@ Value *NewGVN::lookupOperandLeader(Value *V) const { const MemoryAccess *NewGVN::lookupMemoryLeader(const MemoryAccess *MA) const { auto *CC = getMemoryClass(MA); assert(CC->getMemoryLeader() && - "Every MemoryAccess should be mapped to a " - "congruence class with a represenative memory " - "access"); + "Every MemoryAccess should be mapped to a congruence class with a " + "representative memory access"); return CC->getMemoryLeader(); } @@ -1032,7 +1059,7 @@ bool NewGVN::isMemoryAccessTop(const MemoryAccess *MA) const { LoadExpression *NewGVN::createLoadExpression(Type *LoadType, Value *PointerOp, LoadInst *LI, - const MemoryAccess *MA) { + const MemoryAccess *MA) const { auto *E = new (ExpressionAllocator) LoadExpression(1, LI, lookupMemoryLeader(MA)); E->allocateOperands(ArgRecycler, ExpressionAllocator); @@ -1050,8 +1077,8 @@ LoadExpression *NewGVN::createLoadExpression(Type *LoadType, Value *PointerOp, return E; } -const StoreExpression *NewGVN::createStoreExpression(StoreInst *SI, - const MemoryAccess *MA) { +const StoreExpression * +NewGVN::createStoreExpression(StoreInst *SI, const MemoryAccess *MA) const { auto *StoredValueLeader = lookupOperandLeader(SI->getValueOperand()); auto *E = new (ExpressionAllocator) StoreExpression(SI->getNumOperands(), SI, StoredValueLeader, MA); @@ -1068,7 +1095,7 @@ const StoreExpression *NewGVN::createStoreExpression(StoreInst *SI, return E; } -const Expression *NewGVN::performSymbolicStoreEvaluation(Instruction *I) { +const Expression *NewGVN::performSymbolicStoreEvaluation(Instruction *I) const { // Unlike loads, we never try to eliminate stores, so we do not check if they // are simple and avoid value numbering them. auto *SI = cast<StoreInst>(I); @@ -1126,7 +1153,7 @@ const Expression *NewGVN::performSymbolicStoreEvaluation(Instruction *I) { const Expression * NewGVN::performSymbolicLoadCoercion(Type *LoadType, Value *LoadPtr, LoadInst *LI, Instruction *DepInst, - MemoryAccess *DefiningAccess) { + MemoryAccess *DefiningAccess) const { assert((!LI || LI->isSimple()) && "Not a simple load"); if (auto *DepSI = dyn_cast<StoreInst>(DepInst)) { // Can't forward from non-atomic to atomic without violating memory model. @@ -1201,7 +1228,7 @@ NewGVN::performSymbolicLoadCoercion(Type *LoadType, Value *LoadPtr, return nullptr; } -const Expression *NewGVN::performSymbolicLoadEvaluation(Instruction *I) { +const Expression *NewGVN::performSymbolicLoadEvaluation(Instruction *I) const { auto *LI = cast<LoadInst>(I); // We can eliminate in favor of non-simple loads, but we won't be able to @@ -1239,7 +1266,7 @@ const Expression *NewGVN::performSymbolicLoadEvaluation(Instruction *I) { } const Expression * -NewGVN::performSymbolicPredicateInfoEvaluation(Instruction *I) { +NewGVN::performSymbolicPredicateInfoEvaluation(Instruction *I) const { auto *PI = PredInfo->getPredicateInfoFor(I); if (!PI) return nullptr; @@ -1284,7 +1311,7 @@ NewGVN::performSymbolicPredicateInfoEvaluation(Instruction *I) { return nullptr; if (CopyOf != Cmp->getOperand(0) && CopyOf != Cmp->getOperand(1)) { - DEBUG(dbgs() << "Copy is not of any condition operands!"); + DEBUG(dbgs() << "Copy is not of any condition operands!\n"); return nullptr; } Value *FirstOp = lookupOperandLeader(Cmp->getOperand(0)); @@ -1329,7 +1356,7 @@ NewGVN::performSymbolicPredicateInfoEvaluation(Instruction *I) { } // Evaluate read only and pure calls, and create an expression result. -const Expression *NewGVN::performSymbolicCallEvaluation(Instruction *I) { +const Expression *NewGVN::performSymbolicCallEvaluation(Instruction *I) const { auto *CI = cast<CallInst>(I); if (auto *II = dyn_cast<IntrinsicInst>(I)) { // Instrinsics with the returned attribute are copies of arguments. @@ -1366,8 +1393,7 @@ bool NewGVN::setMemoryClass(const MemoryAccess *From, DEBUG(dbgs() << "Setting " << *From); DEBUG(dbgs() << " equivalent to congruence class "); DEBUG(dbgs() << NewClass->getID() << " with current MemoryAccess leader "); - DEBUG(dbgs() << *NewClass->getMemoryLeader()); - DEBUG(dbgs() << "\n"); + DEBUG(dbgs() << *NewClass->getMemoryLeader() << "\n"); auto LookupResult = MemoryAccessToClass.find(From); bool Changed = false; @@ -1381,7 +1407,7 @@ bool NewGVN::setMemoryClass(const MemoryAccess *From, NewClass->memory_insert(MP); // This may have killed the class if it had no non-memory members if (OldClass->getMemoryLeader() == From) { - if (OldClass->memory_empty()) { + if (OldClass->definesNoMemory()) { OldClass->setMemoryLeader(nullptr); } else { OldClass->setMemoryLeader(getNextMemoryLeader(OldClass)); @@ -1406,7 +1432,7 @@ bool NewGVN::setMemoryClass(const MemoryAccess *From, // Determine if a phi is cycle-free. That means the values in the phi don't // depend on any expressions that can change value as a result of the phi. // For example, a non-cycle free phi would be v = phi(0, v+1). -bool NewGVN::isCycleFree(const PHINode *PN) { +bool NewGVN::isCycleFree(const PHINode *PN) const { // In order to compute cycle-freeness, we do SCC finding on the phi, and see // what kind of SCC it ends up in. If it is a singleton, it is cycle-free. // If it is not in a singleton, it is only cycle free if the other members are @@ -1436,7 +1462,7 @@ bool NewGVN::isCycleFree(const PHINode *PN) { } // Evaluate PHI nodes symbolically, and create an expression result. -const Expression *NewGVN::performSymbolicPHIEvaluation(Instruction *I) { +const Expression *NewGVN::performSymbolicPHIEvaluation(Instruction *I) const { // True if one of the incoming phi edges is a backedge. bool HasBackedge = false; // All constant tracks the state of whether all the *original* phi operands @@ -1510,7 +1536,8 @@ const Expression *NewGVN::performSymbolicPHIEvaluation(Instruction *I) { return E; } -const Expression *NewGVN::performSymbolicAggrValueEvaluation(Instruction *I) { +const Expression * +NewGVN::performSymbolicAggrValueEvaluation(Instruction *I) const { if (auto *EI = dyn_cast<ExtractValueInst>(I)) { auto *II = dyn_cast<IntrinsicInst>(EI->getAggregateOperand()); if (II && EI->getNumIndices() == 1 && *EI->idx_begin() == 0) { @@ -1548,7 +1575,7 @@ const Expression *NewGVN::performSymbolicAggrValueEvaluation(Instruction *I) { return createAggregateValueExpression(I); } -const Expression *NewGVN::performSymbolicCmpEvaluation(Instruction *I) { +const Expression *NewGVN::performSymbolicCmpEvaluation(Instruction *I) const { auto *CI = dyn_cast<CmpInst>(I); // See if our operands are equal to those of a previous predicate, and if so, // if it implies true or false. @@ -1663,7 +1690,7 @@ const Expression *NewGVN::performSymbolicCmpEvaluation(Instruction *I) { } // Substitute and symbolize the value before value numbering. -const Expression *NewGVN::performSymbolicEvaluation(Value *V) { +const Expression *NewGVN::performSymbolicEvaluation(Value *V) const { const Expression *E = nullptr; if (auto *C = dyn_cast<Constant>(V)) E = createConstantExpression(C); @@ -1749,7 +1776,7 @@ void NewGVN::markUsersTouched(Value *V) { } } -void NewGVN::addMemoryUsers(const MemoryAccess *To, MemoryAccess *U) { +void NewGVN::addMemoryUsers(const MemoryAccess *To, MemoryAccess *U) const { DEBUG(dbgs() << "Adding memory user " << *U << " to " << *To << "\n"); MemoryToUsers[To].insert(U); } @@ -1772,7 +1799,7 @@ void NewGVN::markMemoryUsersTouched(const MemoryAccess *MA) { } // Add I to the set of users of a given predicate. -void NewGVN::addPredicateUsers(const PredicateBase *PB, Instruction *I) { +void NewGVN::addPredicateUsers(const PredicateBase *PB, Instruction *I) const { if (auto *PBranch = dyn_cast<PredicateBranch>(PB)) PredicateToUsers[PBranch->Condition].insert(I); else if (auto *PAssume = dyn_cast<PredicateBranch>(PB)) @@ -1825,8 +1852,7 @@ const MemoryAccess *NewGVN::getNextMemoryLeader(CongruenceClass *CC) const { // TODO: If this ends up to slow, we can maintain a next memory leader like we // do for regular leaders. // Make sure there will be a leader to find - assert((CC->getStoreCount() > 0 || !CC->memory_empty()) && - "Can't get next leader if there is none"); + assert(!CC->definesNoMemory() && "Can't get next leader if there is none"); if (CC->getStoreCount() > 0) { if (auto *NL = dyn_cast_or_null<StoreInst>(CC->getNextLeader().first)) return MSSA->getMemoryAccess(NL); @@ -1898,7 +1924,7 @@ void NewGVN::moveMemoryToNewCongruenceClass(Instruction *I, setMemoryClass(InstMA, NewClass); // Now, fixup the old class if necessary if (OldClass->getMemoryLeader() == InstMA) { - if (OldClass->getStoreCount() != 0 || !OldClass->memory_empty()) { + if (!OldClass->definesNoMemory()) { OldClass->setMemoryLeader(getNextMemoryLeader(OldClass)); DEBUG(dbgs() << "Memory class leader change for class " << OldClass->getID() << " to " @@ -1956,10 +1982,9 @@ void NewGVN::moveValueToNewCongruenceClass(Instruction *I, const Expression *E, if (NewClass->getStoreCount() == 0 && !NewClass->getStoredValue()) { // If it's a store expression we are using, it means we are not equivalent // to something earlier. - if (isa<StoreExpression>(E)) { - assert(lookupOperandLeader(SI->getValueOperand()) != - NewClass->getLeader()); - NewClass->setStoredValue(lookupOperandLeader(SI->getValueOperand())); + if (auto *SE = dyn_cast<StoreExpression>(E)) { + assert(SE->getStoredValue() != NewClass->getLeader()); + NewClass->setStoredValue(SE->getStoredValue()); markValueLeaderChangeTouched(NewClass); // Shift the new class leader to be the store DEBUG(dbgs() << "Changing leader of congruence class " @@ -1985,7 +2010,7 @@ void NewGVN::moveValueToNewCongruenceClass(Instruction *I, const Expression *E, // See if we destroyed the class or need to swap leaders. if (OldClass->empty() && OldClass != TOPClass) { if (OldClass->getDefiningExpr()) { - DEBUG(dbgs() << "Erasing expression " << OldClass->getDefiningExpr() + DEBUG(dbgs() << "Erasing expression " << *OldClass->getDefiningExpr() << " from table\n"); ExpressionToClass.erase(OldClass->getDefiningExpr()); } @@ -2064,7 +2089,7 @@ void NewGVN::performCongruenceFinding(Instruction *I, const Expression *E) { } else if (const auto *SE = dyn_cast<StoreExpression>(E)) { StoreInst *SI = SE->getStoreInst(); NewClass->setLeader(SI); - NewClass->setStoredValue(lookupOperandLeader(SI->getValueOperand())); + NewClass->setStoredValue(SE->getStoredValue()); // The RepMemoryAccess field will be filled in properly by the // moveValueToNewCongruenceClass call. } else { @@ -2523,6 +2548,19 @@ void NewGVN::verifyMemoryCongruency() const { return false; if (auto *MemDef = dyn_cast<MemoryDef>(Pair.first)) return !isInstructionTriviallyDead(MemDef->getMemoryInst()); + + // We could have phi nodes which operands are all trivially dead, + // so we don't process them. + if (auto *MemPHI = dyn_cast<MemoryPhi>(Pair.first)) { + for (auto &U : MemPHI->incoming_values()) { + if (Instruction *I = dyn_cast<Instruction>(U.get())) { + if (!isInstructionTriviallyDead(I)) + return true; + } + } + return false; + } + return true; }; |