diff options
| -rw-r--r-- | lib/Transforms/IPO/FunctionAttrs.cpp | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/lib/Transforms/IPO/FunctionAttrs.cpp b/lib/Transforms/IPO/FunctionAttrs.cpp index a2173933ef..71671d6fe9 100644 --- a/lib/Transforms/IPO/FunctionAttrs.cpp +++ b/lib/Transforms/IPO/FunctionAttrs.cpp @@ -152,6 +152,25 @@ bool FunctionAttrs::AddReadAttrs(const CallGraphSCC &SCC) { } // Only reads and writes local memory. continue; + case AliasAnalysis::AccessesArgumentsReadonly: + // Check whether all pointer arguments point to local memory, and + // ignore calls that only access local memory. + for (CallSite::arg_iterator CI = CS.arg_begin(), CE = CS.arg_end(); + CI != CE; ++CI) { + Value *Arg = *CI; + if (Arg->getType()->isPointerTy()) { + AliasAnalysis::Location Loc(Arg, + AliasAnalysis::UnknownSize, + I->getMetadata(LLVMContext::MD_tbaa)); + if (!AA->pointsToConstantMemory(Loc, /*OrLocal=*/true)) { + // Reads non-local memory. + ReadsMemory = true; + break; + } + } + } + // Only reads memory. + continue; default: // Otherwise, be conservative. break; |