Handle intrinsics in GlobalsModRef. Fixes pr12351.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153604 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 0 deletions

diff --git a/lib/Analysis/IPA/GlobalsModRef.cpp b/lib/Analysis/IPA/GlobalsModRef.cpp
index b226d66cd7..c1d8e3e65a 100644
--- a/lib/Analysis/IPA/GlobalsModRef.cpp
+++ b/lib/Analysis/IPA/GlobalsModRef.cpp
@@ -21,6 +21,7 @@
 #include "llvm/Instructions.h"
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
+#include "llvm/IntrinsicInst.h"
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Analysis/CallGraph.h"
 #include "llvm/Analysis/MemoryBuiltins.h"
@@ -467,6 +468,11 @@ void GlobalsModRef::AnalyzeCallGraph(CallGraph &CG, Module &M) {
         } else if (isMalloc(&cast<Instruction>(*II)) ||
                    isFreeCall(&cast<Instruction>(*II))) {
           FunctionEffect |= ModRef;
+        } else if (IntrinsicInst *Intrinsic = dyn_cast<IntrinsicInst>(&*II)) {
+          // The callgraph doesn't include intrinsic calls.
+          Function *Callee = Intrinsic->getCalledFunction();
+          ModRefBehavior Behaviour = AliasAnalysis::getModRefBehavior(Callee);
+          FunctionEffect |= (Behaviour & ModRef);
         }
 
     if ((FunctionEffect & Mod) == 0)