diff options
Diffstat (limited to 'lib/Transforms/InstCombine/InstructionCombining.cpp')
-rw-r--r-- | lib/Transforms/InstCombine/InstructionCombining.cpp | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp index dc7fe5cf6b..c6115e3e91 100644 --- a/lib/Transforms/InstCombine/InstructionCombining.cpp +++ b/lib/Transforms/InstCombine/InstructionCombining.cpp @@ -162,6 +162,21 @@ static bool MaintainNoSignedWrap(BinaryOperator &I, Value *B, Value *C) { return !Overflow; } +/// Conservatively clears subclassOptionalData after a reassociation or +/// commutation. We preserve fast-math flags when applicable as they can be +/// preserved. +static void ClearSubclassDataAfterReassociation(BinaryOperator &I) { + FPMathOperator *FPMO = dyn_cast<FPMathOperator>(&I); + if (!FPMO) { + I.clearSubclassOptionalData(); + return; + } + + FastMathFlags FMF = I.getFastMathFlags(); + I.clearSubclassOptionalData(); + I.setFastMathFlags(FMF); +} + /// SimplifyAssociativeOrCommutative - This performs a few simplifications for /// operators which are associative or commutative: // @@ -219,7 +234,7 @@ bool InstCombiner::SimplifyAssociativeOrCommutative(BinaryOperator &I) { I.clearSubclassOptionalData(); I.setHasNoSignedWrap(true); } else { - I.clearSubclassOptionalData(); + ClearSubclassDataAfterReassociation(I); } Changed = true; @@ -241,7 +256,7 @@ bool InstCombiner::SimplifyAssociativeOrCommutative(BinaryOperator &I) { I.setOperand(1, C); // Conservatively clear the optional flags, since they may not be // preserved by the reassociation. - I.clearSubclassOptionalData(); + ClearSubclassDataAfterReassociation(I); Changed = true; ++NumReassoc; continue; @@ -263,7 +278,7 @@ bool InstCombiner::SimplifyAssociativeOrCommutative(BinaryOperator &I) { I.setOperand(1, B); // Conservatively clear the optional flags, since they may not be // preserved by the reassociation. - I.clearSubclassOptionalData(); + ClearSubclassDataAfterReassociation(I); Changed = true; ++NumReassoc; continue; @@ -283,7 +298,7 @@ bool InstCombiner::SimplifyAssociativeOrCommutative(BinaryOperator &I) { I.setOperand(1, V); // Conservatively clear the optional flags, since they may not be // preserved by the reassociation. - I.clearSubclassOptionalData(); + ClearSubclassDataAfterReassociation(I); Changed = true; ++NumReassoc; continue; @@ -310,7 +325,7 @@ bool InstCombiner::SimplifyAssociativeOrCommutative(BinaryOperator &I) { I.setOperand(1, Folded); // Conservatively clear the optional flags, since they may not be // preserved by the reassociation. - I.clearSubclassOptionalData(); + ClearSubclassDataAfterReassociation(I); Changed = true; continue; |