diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp index 2722a66aebf3..d98693a88571 100644 --- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp +++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp @@ -625,10 +625,10 @@ void IndVarSimplify::SinkUnusedInvariants(Loop *L) { /// Return true if it is OK to use SIToFPInst for an induction variable /// with given initial and exit values. -static bool useSIToFPInst(ConstantFP &InitV, ConstantFP &ExitV, +static bool useSIToFPInst(ConstantFP *InitV, ConstantFP *ExitV, uint64_t intIV, uint64_t intEV) { - if (InitV.getValueAPF().isNegative() || ExitV.getValueAPF().isNegative()) + if (InitV->getValueAPF().isNegative() || ExitV->getValueAPF().isNegative()) return true; // If the iteration range can be handled by SIToFPInst then use it. @@ -640,19 +640,16 @@ static bool useSIToFPInst(ConstantFP &InitV, ConstantFP &ExitV, } /// convertToInt - Convert APF to an integer, if possible. -static bool convertToInt(const APFloat &APF, uint64_t *intVal) { - +static bool convertToInt(const APFloat &APF, uint64_t &intVal) { bool isExact = false; if (&APF.getSemantics() == &APFloat::PPCDoubleDouble) return false; - if (APF.convertToInteger(intVal, 32, APF.isNegative(), - APFloat::rmTowardZero, &isExact) - != APFloat::opOK) + if (APF.convertToInteger(&intVal, 32, APF.isNegative(), + APFloat::rmTowardZero, &isExact) != APFloat::opOK) return false; if (!isExact) return false; return true; - } /// HandleFloatingPointIV - If the loop has floating induction variable @@ -665,64 +662,53 @@ static bool convertToInt(const APFloat &APF, uint64_t *intVal) { /// bar((double)i); /// void IndVarSimplify::HandleFloatingPointIV(Loop *L, PHINode *PH) { - unsigned IncomingEdge = L->contains(PH->getIncomingBlock(0)); unsigned BackEdge = IncomingEdge^1; // Check incoming value. - ConstantFP *InitValue = dyn_cast(PH->getIncomingValue(IncomingEdge)); + ConstantFP *InitValue = + dyn_cast(PH->getIncomingValue(IncomingEdge)); if (!InitValue) return; - uint64_t newInitValue = - Type::getInt32Ty(PH->getContext())->getPrimitiveSizeInBits(); - if (!convertToInt(InitValue->getValueAPF(), &newInitValue)) + + uint64_t newInitValue; + if (!convertToInt(InitValue->getValueAPF(), newInitValue)) return; // Check IV increment. Reject this PH if increment operation is not // an add or increment value can not be represented by an integer. BinaryOperator *Incr = dyn_cast(PH->getIncomingValue(BackEdge)); - if (!Incr) return; - if (Incr->getOpcode() != Instruction::FAdd) return; - ConstantFP *IncrValue = NULL; - unsigned IncrVIndex = 1; - if (Incr->getOperand(1) == PH) - IncrVIndex = 0; - IncrValue = dyn_cast(Incr->getOperand(IncrVIndex)); - if (!IncrValue) return; - uint64_t newIncrValue = - Type::getInt32Ty(PH->getContext())->getPrimitiveSizeInBits(); - if (!convertToInt(IncrValue->getValueAPF(), &newIncrValue)) + if (Incr == 0 || Incr->getOpcode() != Instruction::FAdd) return; + + // If this is not an add of the PHI with a constantfp, or if the constant fp + // is not an integer, bail out. + ConstantFP *IncrValue = dyn_cast(Incr->getOperand(1)); + uint64_t newIncrValue; + if (IncrValue == 0 || Incr->getOperand(0) != PH || + !convertToInt(IncrValue->getValueAPF(), newIncrValue)) return; - // Check Incr uses. One user is PH and the other users is exit condition used - // by the conditional terminator. + // Check Incr uses. One user is PH and the other user is an exit condition + // used by the conditional terminator. Value::use_iterator IncrUse = Incr->use_begin(); Instruction *U1 = cast(IncrUse++); if (IncrUse == Incr->use_end()) return; Instruction *U2 = cast(IncrUse++); if (IncrUse != Incr->use_end()) return; - // Find exit condition. + // Find exit condition, which is an fcmp. If it doesn't exist, or if it isn't + // only used by a branch, we can't transform it. FCmpInst *EC = dyn_cast(U1); if (!EC) EC = dyn_cast(U2); - if (!EC) return; + if (EC == 0 || !EC->hasOneUse() || !isa(EC->use_back())) + return; - if (BranchInst *BI = dyn_cast(EC->getParent()->getTerminator())) { - if (!BI->isConditional()) return; - if (BI->getCondition() != EC) return; - } - - // Find exit value. If exit value can not be represented as an integer then - // do not handle this floating point PH. - ConstantFP *EV = NULL; - unsigned EVIndex = 1; - if (EC->getOperand(1) == Incr) - EVIndex = 0; - EV = dyn_cast(EC->getOperand(EVIndex)); - if (!EV) return; - uint64_t intEV = Type::getInt32Ty(PH->getContext())->getPrimitiveSizeInBits(); - if (!convertToInt(EV->getValueAPF(), &intEV)) + // If it isn't a comparison with an integer-as-fp (the exit value), we can't + // transform it. + ConstantFP *ExitValueVal = dyn_cast(EC->getOperand(1)); + uint64_t ExitValue; + if (ExitValueVal == 0 || !convertToInt(ExitValueVal->getValueAPF(),ExitValue)) return; // Find new predicate for integer comparison. @@ -769,9 +755,11 @@ void IndVarSimplify::HandleFloatingPointIV(Loop *L, PHINode *PH) { // The back edge is edge 1 of newPHI, whatever it may have been in the // original PHI. ConstantInt *NewEV = ConstantInt::get(Type::getInt32Ty(PH->getContext()), - intEV); - Value *LHS = (EVIndex == 1 ? NewPHI->getIncomingValue(1) : NewEV); - Value *RHS = (EVIndex == 1 ? NewEV : NewPHI->getIncomingValue(1)); + ExitValue); + + // FIXME: This is probably wrong. + Value *LHS = NewPHI->getIncomingValue(1); + Value *RHS = NewEV; ICmpInst *NewEC = new ICmpInst(EC->getParent()->getTerminator(), NewPred, LHS, RHS, EC->getName()); @@ -792,7 +780,7 @@ void IndVarSimplify::HandleFloatingPointIV(Loop *L, PHINode *PH) { // Give SIToFPInst preference over UIToFPInst because it is faster on // platforms that are widely used. if (WeakPH && !PH->use_empty()) { - if (useSIToFPInst(*InitValue, *EV, newInitValue, intEV)) { + if (useSIToFPInst(InitValue, ExitValueVal, newInitValue, ExitValue)) { SIToFPInst *Conv = new SIToFPInst(NewPHI, PH->getType(), "indvar.conv", PH->getParent()->getFirstNonPHI()); PH->replaceAllUsesWith(Conv); diff --git a/llvm/test/Transforms/IndVarSimplify/crash.ll b/llvm/test/Transforms/IndVarSimplify/crash.ll new file mode 100644 index 000000000000..14f79fefb180 --- /dev/null +++ b/llvm/test/Transforms/IndVarSimplify/crash.ll @@ -0,0 +1,19 @@ +; RUN: opt -indvars %s -disable-output + +declare i32 @putchar(i8) nounwind + +define void @t2(i1* %P) nounwind { +;