From 747032522f9f3b2d9bae71aa303c1a0fd953eee9 Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Wed, 20 Jul 2011 21:57:23 +0000 Subject: Clean up includes of llvm/Analysis/ConstantFolding.h so it's included where it's used and not included where it isn't. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135628 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/InstCombine/InstCombineShifts.cpp | 1 + 1 file changed, 1 insertion(+) (limited to 'lib/Transforms/InstCombine/InstCombineShifts.cpp') diff --git a/lib/Transforms/InstCombine/InstCombineShifts.cpp b/lib/Transforms/InstCombine/InstCombineShifts.cpp index 65d1a66..628d7a8 100644 --- a/lib/Transforms/InstCombine/InstCombineShifts.cpp +++ b/lib/Transforms/InstCombine/InstCombineShifts.cpp @@ -13,6 +13,7 @@ #include "InstCombine.h" #include "llvm/IntrinsicInst.h" +#include "llvm/Analysis/ConstantFolding.h" #include "llvm/Analysis/InstructionSimplify.h" #include "llvm/Support/PatternMatch.h" using namespace llvm; -- cgit v1.1 From ef715972423a57febb7aa9b056d9bf6320e74817 Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Fri, 29 Jul 2011 00:18:19 +0000 Subject: Make sure to correctly clear the exact/nuw/nsw flags off of shifts when they are combined together. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136435 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/InstCombine/InstCombineShifts.cpp | 46 ++++++++++++++---------- 1 file changed, 27 insertions(+), 19 deletions(-) (limited to 'lib/Transforms/InstCombine/InstCombineShifts.cpp') diff --git a/lib/Transforms/InstCombine/InstCombineShifts.cpp b/lib/Transforms/InstCombine/InstCombineShifts.cpp index 628d7a8..6d85add 100644 --- a/lib/Transforms/InstCombine/InstCombineShifts.cpp +++ b/lib/Transforms/InstCombine/InstCombineShifts.cpp @@ -208,11 +208,12 @@ static Value *GetShiftedValue(Value *V, unsigned NumBits, bool isLeftShift, return I; case Instruction::Shl: { - unsigned TypeWidth = I->getType()->getScalarSizeInBits(); + BinaryOperator *BO = cast(I); + unsigned TypeWidth = BO->getType()->getScalarSizeInBits(); // We only accept shifts-by-a-constant in CanEvaluateShifted. - ConstantInt *CI = cast(I->getOperand(1)); - + ConstantInt *CI = cast(BO->getOperand(1)); + // We can always fold shl(c1)+shl(c2) -> shl(c1+c2). if (isLeftShift) { // If this is oversized composite shift, then unsigned shifts get 0. @@ -220,7 +221,9 @@ static Value *GetShiftedValue(Value *V, unsigned NumBits, bool isLeftShift, if (NewShAmt >= TypeWidth) return Constant::getNullValue(I->getType()); - I->setOperand(1, ConstantInt::get(I->getType(), NewShAmt)); + BO->setOperand(1, ConstantInt::get(BO->getType(), NewShAmt)); + BO->setHasNoUnsignedWrap(false); + BO->setHasNoSignedWrap(false); return I; } @@ -228,11 +231,11 @@ static Value *GetShiftedValue(Value *V, unsigned NumBits, bool isLeftShift, // zeros. if (CI->getValue() == NumBits) { APInt Mask(APInt::getLowBitsSet(TypeWidth, TypeWidth - NumBits)); - V = IC.Builder->CreateAnd(I->getOperand(0), - ConstantInt::get(I->getContext(), Mask)); + V = IC.Builder->CreateAnd(BO->getOperand(0), + ConstantInt::get(BO->getContext(), Mask)); if (Instruction *VI = dyn_cast(V)) { - VI->moveBefore(I); - VI->takeName(I); + VI->moveBefore(BO); + VI->takeName(BO); } return V; } @@ -240,23 +243,27 @@ static Value *GetShiftedValue(Value *V, unsigned NumBits, bool isLeftShift, // We turn shl(c1)+shr(c2) -> shl(c3)+and(c4), but only when we know that // the and won't be needed. assert(CI->getZExtValue() > NumBits); - I->setOperand(1, ConstantInt::get(I->getType(), - CI->getZExtValue() - NumBits)); - return I; + BO->setOperand(1, ConstantInt::get(BO->getType(), + CI->getZExtValue() - NumBits)); + BO->setHasNoUnsignedWrap(false); + BO->setHasNoSignedWrap(false); + return BO; } case Instruction::LShr: { - unsigned TypeWidth = I->getType()->getScalarSizeInBits(); + BinaryOperator *BO = cast(I); + unsigned TypeWidth = BO->getType()->getScalarSizeInBits(); // We only accept shifts-by-a-constant in CanEvaluateShifted. - ConstantInt *CI = cast(I->getOperand(1)); + ConstantInt *CI = cast(BO->getOperand(1)); // We can always fold lshr(c1)+lshr(c2) -> lshr(c1+c2). if (!isLeftShift) { // If this is oversized composite shift, then unsigned shifts get 0. unsigned NewShAmt = NumBits+CI->getZExtValue(); if (NewShAmt >= TypeWidth) - return Constant::getNullValue(I->getType()); + return Constant::getNullValue(BO->getType()); - I->setOperand(1, ConstantInt::get(I->getType(), NewShAmt)); + BO->setOperand(1, ConstantInt::get(BO->getType(), NewShAmt)); + BO->setIsExact(false); return I; } @@ -265,7 +272,7 @@ static Value *GetShiftedValue(Value *V, unsigned NumBits, bool isLeftShift, if (CI->getValue() == NumBits) { APInt Mask(APInt::getHighBitsSet(TypeWidth, TypeWidth - NumBits)); V = IC.Builder->CreateAnd(I->getOperand(0), - ConstantInt::get(I->getContext(), Mask)); + ConstantInt::get(BO->getContext(), Mask)); if (Instruction *VI = dyn_cast(V)) { VI->moveBefore(I); VI->takeName(I); @@ -276,9 +283,10 @@ static Value *GetShiftedValue(Value *V, unsigned NumBits, bool isLeftShift, // We turn lshr(c1)+shl(c2) -> lshr(c3)+and(c4), but only when we know that // the and won't be needed. assert(CI->getZExtValue() > NumBits); - I->setOperand(1, ConstantInt::get(I->getType(), - CI->getZExtValue() - NumBits)); - return I; + BO->setOperand(1, ConstantInt::get(BO->getType(), + CI->getZExtValue() - NumBits)); + BO->setIsExact(false); + return BO; } case Instruction::Select: -- cgit v1.1