diff options
| author | David Greene <greened@obbligato.org> | 2009-05-05 20:22:36 +0000 |
|---|---|---|
| committer | David Greene <greened@obbligato.org> | 2009-05-05 20:22:36 +0000 |
| commit | 58deef5559db65f742fc67adcdaba04ce83f0764 (patch) | |
| tree | 96a70492ad59983bc77c40d53ba036f2d72fb8f1 /lib/Transforms | |
| parent | 1777d0c6c555fb20177b3a60b40eef265c2b842a (diff) | |
Handle overflow of 64-bit loop conditions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71008 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Transforms')
| -rw-r--r-- | lib/Transforms/Scalar/LoopStrengthReduce.cpp | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp index 4365adc629..23f75630b7 100644 --- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -2027,9 +2027,10 @@ ICmpInst *LoopStrengthReduce::ChangeCompareStride(Loop *L, ICmpInst *Cond, Scale = SSInt / CmpSSInt; int64_t NewCmpVal = CmpVal * Scale; - APInt Mul = APInt(BitWidth, NewCmpVal); + APInt Mul = APInt(BitWidth*2, CmpVal); + Mul = Mul * APInt(BitWidth*2, Scale); // Check for overflow. - if (Mul.getSExtValue() != NewCmpVal) + if (!Mul.isSignedIntN(BitWidth)) continue; // Watch out for overflow. |