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| author | Chen Zheng <czhengsz@cn.ibm.com> | 2019-04-08 12:08:03 +0000 |
|---|---|---|
| committer | Chen Zheng <czhengsz@cn.ibm.com> | 2019-04-08 12:08:03 +0000 |
| commit | 923c7c9daaa5d90be4f2bcc58652a2c925a3c4db (patch) | |
| tree | 12b82871558d051f2dd0a601aaa6f536cf0a3f50 /llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp | |
| parent | 0df95d2d31279fdeb6370e0c6d71003607af9c8d (diff) | |
| download | bcm5719-llvm-923c7c9daaa5d90be4f2bcc58652a2c925a3c4db.tar.gz bcm5719-llvm-923c7c9daaa5d90be4f2bcc58652a2c925a3c4db.zip | |
[InstCombine] sdiv exact flag fixup.
Differential Revision: https://reviews.llvm.org/D60396
llvm-svn: 357904
Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp index 6d743a26098..d5a36e025f6 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp @@ -1693,8 +1693,11 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) { // 0 - (X sdiv C) -> (X sdiv -C) provided the negation doesn't overflow. if (match(Op1, m_SDiv(m_Value(X), m_Constant(C))) && match(Op0, m_Zero()) && - C->isNotMinSignedValue() && !C->isOneValue()) - return BinaryOperator::CreateSDiv(X, ConstantExpr::getNeg(C)); + C->isNotMinSignedValue() && !C->isOneValue()) { + auto *BO = BinaryOperator::CreateSDiv(X, ConstantExpr::getNeg(C)); + BO->setIsExact(cast<BinaryOperator>(Op1)->isExact()); + return BO; + } // 0 - (X << Y) -> (-X << Y) when X is freely negatable. if (match(Op1, m_Shl(m_Value(X), m_Value(Y))) && match(Op0, m_Zero())) |
