diff options
| -rw-r--r-- | lib/Analysis/BasicAliasAnalysis.cpp | 6 | ||||
| -rw-r--r-- | test/Analysis/BasicAA/2010-09-15-GEP-SignedArithmetic.ll | 15 |
2 files changed, 18 insertions, 3 deletions
diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp index 69a1c0c..32a1726 100644 --- a/lib/Analysis/BasicAliasAnalysis.cpp +++ b/lib/Analysis/BasicAliasAnalysis.cpp @@ -386,8 +386,8 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs, // The GEP index scale ("Scale") scales C1*V+C2, yielding (C1*V+C2)*Scale. // This gives us an aggregate computation of (C1*Scale)*V + C2*Scale. - BaseOffs += IndexOffset.getZExtValue()*Scale; - Scale *= IndexScale.getZExtValue(); + BaseOffs += IndexOffset.getSExtValue()*Scale; + Scale *= IndexScale.getSExtValue(); // If we already had an occurrance of this index variable, merge this @@ -407,7 +407,7 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs, // pointer size. if (unsigned ShiftBits = 64-TD->getPointerSizeInBits()) { Scale <<= ShiftBits; - Scale >>= ShiftBits; + Scale = (int64_t)Scale >> ShiftBits; } if (Scale) { diff --git a/test/Analysis/BasicAA/2010-09-15-GEP-SignedArithmetic.ll b/test/Analysis/BasicAA/2010-09-15-GEP-SignedArithmetic.ll new file mode 100644 index 0000000..2b0cd78 --- /dev/null +++ b/test/Analysis/BasicAA/2010-09-15-GEP-SignedArithmetic.ll @@ -0,0 +1,15 @@ +; RUN: opt < %s -basicaa -aa-eval -print-all-alias-modref-info -disable-output |& grep {1 may alias} +; PR7959 + +target datalayout = "e-p:32:32:32" + +define i32 @test(i32* %tab, i32 %indvar) nounwind { + %tmp31 = mul i32 %indvar, -2 + %tmp32 = add i32 %tmp31, 30 + %t.5 = getelementptr i32* %tab, i32 %tmp32 + %loada = load i32* %tab + store i32 0, i32* %t.5 + %loadb = load i32* %tab + %rval = add i32 %loada, %loadb + ret i32 %rval +} |