diff options
| -rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 3c260d310c..a4d3c54e1c 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -51,6 +51,10 @@ namespace { CombinerAA("combiner-alias-analysis", cl::Hidden, cl::desc("Turn on alias analysis during testing")); + static cl::opt<bool> + CombinerGlobalAA("combiner-global-alias-analysis", cl::Hidden, + cl::desc("Include global information in alias analysis")); + //------------------------------ DAGCombiner ---------------------------------// class VISIBILITY_HIDDEN DAGCombiner { @@ -4036,13 +4040,15 @@ bool DAGCombiner::isAlias(SDOperand Ptr1, int64_t Size1, // If we know both bases then they can't alias. if (KnownBase1 && KnownBase2) return false; - // Use alias analysis information. - int Overlap1 = Size1 + SrcValueOffset1 + Offset1; - int Overlap2 = Size2 + SrcValueOffset2 + Offset2; - AliasAnalysis::AliasResult AAResult = + if (CombinerGlobalAA) { + // Use alias analysis information. + int Overlap1 = Size1 + SrcValueOffset1 + Offset1; + int Overlap2 = Size2 + SrcValueOffset2 + Offset2; + AliasAnalysis::AliasResult AAResult = AA.alias(SrcValue1, Overlap1, SrcValue2, Overlap2); - if (AAResult == AliasAnalysis::NoAlias) - return false; + if (AAResult == AliasAnalysis::NoAlias) + return false; + } // Otherwise we have to assume they alias. return true; |