Changes in directory llvm/lib/VMCore:
ConstantFold.cpp updated: 1.140 -> 1.141 --- Log message: For PR1205: http://llvm.org/PR1205 : Implement review feedback: 1. Use new APInt::RoundDoubleToAPInt interface to specify the bit width so that we don't have to truncate or extend in constant folding. 2. Fix a pasteo in SDiv that prevented a check for overflow. 3. Fix the shift operators: undef happens when the shift amount is equal to the bitwidth. --- Diffs of the changes: (+5 -14) ConstantFold.cpp | 19 +++++-------------- 1 files changed, 5 insertions(+), 14 deletions(-) Index: llvm/lib/VMCore/ConstantFold.cpp diff -u llvm/lib/VMCore/ConstantFold.cpp:1.140 llvm/lib/VMCore/ConstantFold.cpp:1.141 --- llvm/lib/VMCore/ConstantFold.cpp:1.140 Tue Feb 27 00:23:51 2007 +++ llvm/lib/VMCore/ConstantFold.cpp Tue Feb 27 13:29:54 2007 @@ -176,23 +176,15 @@ return 0; // Can't fold. case Instruction::FPToUI: if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V)) { - APInt Val(APIntOps::RoundDoubleToAPInt(FPC->getValue())); uint32_t DestBitWidth = cast<IntegerType>(DestTy)->getBitWidth(); - if (Val.getBitWidth() > DestBitWidth) - Val.trunc(DestBitWidth); - else if (Val.getBitWidth() < DestBitWidth) - Val.zext(DestBitWidth); + APInt Val(APIntOps::RoundDoubleToAPInt(FPC->getValue(), DestBitWidth)); return ConstantInt::get(DestTy, Val); } return 0; // Can't fold. case Instruction::FPToSI: if (const ConstantFP *FPC = dyn_cast<ConstantFP>(V)) { - APInt Val(APIntOps::RoundDoubleToAPInt(FPC->getValue())); uint32_t DestBitWidth = cast<IntegerType>(DestTy)->getBitWidth(); - if (Val.getBitWidth() > DestBitWidth) - Val.trunc(DestBitWidth); - else if (Val.getBitWidth() < DestBitWidth) - Val.sext(DestBitWidth); + APInt Val(APIntOps::RoundDoubleToAPInt(FPC->getValue(), DestBitWidth)); return ConstantInt::get(DestTy, Val); } return 0; // Can't fold. @@ -604,7 +596,6 @@ case Instruction::SDiv: if (CI2->isNullValue()) return 0; // X / 0 -> can't fold - return ConstantInt::get(C1->getType(), C1V.sdiv(C2V)); if (C2V.isAllOnesValue() && C1V.isMinSignedValue()) return 0; // MIN_INT / -1 -> overflow return ConstantInt::get(C1->getType(), C1V.sdiv(C2V)); @@ -626,21 +617,21 @@ return ConstantInt::get(C1->getType(), C1V ^ C2V); case Instruction::Shl: if (uint32_t shiftAmt = C2V.getZExtValue()) - if (shiftAmt <= C1V.getBitWidth()) + if (shiftAmt < C1V.getBitWidth()) return ConstantInt::get(C1->getType(), C1V.shl(shiftAmt)); else return UndefValue::get(C1->getType()); // too big shift is undef return const_cast<ConstantInt*>(CI1); // Zero shift is identity case Instruction::LShr: if (uint32_t shiftAmt = C2V.getZExtValue()) - if (shiftAmt <= C1V.getBitWidth()) + if (shiftAmt < C1V.getBitWidth()) return ConstantInt::get(C1->getType(), C1V.lshr(shiftAmt)); else return UndefValue::get(C1->getType()); // too big shift is undef return const_cast<ConstantInt*>(CI1); // Zero shift is identity case Instruction::AShr: if (uint32_t shiftAmt = C2V.getZExtValue()) - if (shiftAmt <= C1V.getBitWidth()) + if (shiftAmt < C1V.getBitWidth()) return ConstantInt::get(C1->getType(), C1V.ashr(shiftAmt)); else return UndefValue::get(C1->getType()); // too big shift is undef _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
