diff options
Diffstat (limited to 'llvm/lib/Analysis/ScalarEvolution.cpp')
-rw-r--r-- | llvm/lib/Analysis/ScalarEvolution.cpp | 27 |
1 files changed, 7 insertions, 20 deletions
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp index 6480c2c..38bac43 100644 --- a/llvm/lib/Analysis/ScalarEvolution.cpp +++ b/llvm/lib/Analysis/ScalarEvolution.cpp @@ -2244,35 +2244,22 @@ StrengthenNoWrapFlags(ScalarEvolution *SE, SCEVTypes Type, SignOrUnsignWrap = ScalarEvolution::maskFlags(Flags, SignOrUnsignMask); - if (SignOrUnsignWrap != SignOrUnsignMask && - (Type == scAddExpr || Type == scMulExpr) && Ops.size() == 2 && - isa<SCEVConstant>(Ops[0])) { - - auto Opcode = [&] { - switch (Type) { - case scAddExpr: - return Instruction::Add; - case scMulExpr: - return Instruction::Mul; - default: - llvm_unreachable("Unexpected SCEV op."); - } - }(); + if (SignOrUnsignWrap != SignOrUnsignMask && Type == scAddExpr && + Ops.size() == 2 && isa<SCEVConstant>(Ops[0])) { - const APInt &C = cast<SCEVConstant>(Ops[0])->getAPInt(); + // (A + C) --> (A + C)<nsw> if the addition does not sign overflow + // (A + C) --> (A + C)<nuw> if the addition does not unsign overflow - // (A <opcode> C) --> (A <opcode> C)<nsw> if the op doesn't sign overflow. + const APInt &C = cast<SCEVConstant>(Ops[0])->getAPInt(); if (!(SignOrUnsignWrap & SCEV::FlagNSW)) { auto NSWRegion = ConstantRange::makeGuaranteedNoWrapRegion( - Opcode, C, OBO::NoSignedWrap); + Instruction::Add, C, OBO::NoSignedWrap); if (NSWRegion.contains(SE->getSignedRange(Ops[1]))) Flags = ScalarEvolution::setFlags(Flags, SCEV::FlagNSW); } - - // (A <opcode> C) --> (A <opcode> C)<nuw> if the op doesn't unsign overflow. if (!(SignOrUnsignWrap & SCEV::FlagNUW)) { auto NUWRegion = ConstantRange::makeGuaranteedNoWrapRegion( - Opcode, C, OBO::NoUnsignedWrap); + Instruction::Add, C, OBO::NoUnsignedWrap); if (NUWRegion.contains(SE->getUnsignedRange(Ops[1]))) Flags = ScalarEvolution::setFlags(Flags, SCEV::FlagNUW); } |