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| author | Florian Hahn <flo@fhahn.com> | 2021-06-30 19:41:57 +0100 |
|---|---|---|
| committer | Florian Hahn <flo@fhahn.com> | 2021-06-30 20:04:39 +0100 |
| commit | e6d22d0174e09fa01342d9ed1dca47bc1eb58303 (patch) | |
| tree | dc2abb58391ae6feec5137305b223f543dbae1ba /llvm/lib/Analysis/BasicAliasAnalysis.cpp | |
| parent | f4ea6531e677b1a3c107d7009a7e2f195c8fa915 (diff) | |
| download | llvm-e6d22d0174e09fa01342d9ed1dca47bc1eb58303.zip llvm-e6d22d0174e09fa01342d9ed1dca47bc1eb58303.tar.gz llvm-e6d22d0174e09fa01342d9ed1dca47bc1eb58303.tar.bz2 | |
[BasicAA] Use separate scale variable for GCD.
Use separate variable for adjusted scale used for GCD computations. This
fixes an issue where we incorrectly determined that all indices are
non-negative and returned noalias because of that.
Follow up to 91fa3565da16.
Diffstat (limited to 'llvm/lib/Analysis/BasicAliasAnalysis.cpp')
| -rw-r--r-- | llvm/lib/Analysis/BasicAliasAnalysis.cpp | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp index da489b8..d79df62 100644 --- a/llvm/lib/Analysis/BasicAliasAnalysis.cpp +++ b/llvm/lib/Analysis/BasicAliasAnalysis.cpp @@ -1148,14 +1148,15 @@ AliasResult BasicAAResult::aliasGEP( bool AllNonPositive = DecompGEP1.Offset.isNonPositive(); for (unsigned i = 0, e = DecompGEP1.VarIndices.size(); i != e; ++i) { APInt Scale = DecompGEP1.VarIndices[i].Scale; + APInt ScaleForGDC = DecompGEP1.VarIndices[i].Scale; if (!DecompGEP1.VarIndices[i].IsNSW) - Scale = APInt::getOneBitSet(Scale.getBitWidth(), - Scale.countTrailingZeros()); + ScaleForGDC = APInt::getOneBitSet(Scale.getBitWidth(), + Scale.countTrailingZeros()); if (i == 0) - GCD = Scale.abs(); + GCD = ScaleForGDC.abs(); else - GCD = APIntOps::GreatestCommonDivisor(GCD, Scale.abs()); + GCD = APIntOps::GreatestCommonDivisor(GCD, ScaleForGDC.abs()); if (AllNonNegative || AllNonPositive) { // If the Value could change between cycles, then any reasoning about |