When analyzing functions known to only access argument pointees,

only check arguments with pointer types. Update the documentation
of IntrReadArgMem reflect this.

While here, add support for TBAA tags on intrinsic calls.

llvm-svn: 130317

1 files changed, 28 insertions, 9 deletions

diff --git a/llvm/lib/Analysis/AliasAnalysis.cpp b/llvm/lib/Analysis/AliasAnalysis.cpp
index be02ddbaa53..c189a004292 100644
--- a/llvm/lib/Analysis/AliasAnalysis.cpp
+++ b/llvm/lib/Analysis/AliasAnalysis.cpp
@@ -86,14 +86,20 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS,
 
   if (onlyAccessesArgPointees(MRB)) {
     bool doesAlias = false;
-    if (doesAccessArgPointees(MRB))
+    if (doesAccessArgPointees(MRB)) {
+      MDNode *CSTag = CS.getInstruction()->getMetadata(LLVMContext::MD_tbaa);
       for (ImmutableCallSite::arg_iterator AI = CS.arg_begin(), AE = CS.arg_end();
-           AI != AE; ++AI)
-        if (!isNoAlias(Location(*AI), Loc)) {
+           AI != AE; ++AI) {
+        const Value *Arg = *AI;
+        if (!Arg->getType()->isPointerTy())
+          continue;
+        Location CSLoc(Arg, UnknownSize, CSTag);
+        if (!isNoAlias(CSLoc, Loc)) {
           doesAlias = true;
           break;
         }
-
+      }
+    }
     if (!doesAlias)
       return NoModRef;
   }
@@ -138,13 +144,19 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS1, ImmutableCallSite CS2) {
   // CS2's arguments.
   if (onlyAccessesArgPointees(CS2B)) {
     AliasAnalysis::ModRefResult R = NoModRef;
-    if (doesAccessArgPointees(CS2B))
+    if (doesAccessArgPointees(CS2B)) {
+      MDNode *CS2Tag = CS2.getInstruction()->getMetadata(LLVMContext::MD_tbaa);
       for (ImmutableCallSite::arg_iterator
            I = CS2.arg_begin(), E = CS2.arg_end(); I != E; ++I) {
-        R = ModRefResult((R | getModRefInfo(CS1, *I, UnknownSize)) & Mask);
+        const Value *Arg = *I;
+        if (!Arg->getType()->isPointerTy())
+          continue;
+        Location CS2Loc(Arg, UnknownSize, CS2Tag);
+        R = ModRefResult((R | getModRefInfo(CS1, CS2Loc)) & Mask);
         if (R == Mask)
           break;
       }
+    }
     return R;
   }
 
@@ -152,13 +164,20 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS1, ImmutableCallSite CS2) {
   // any of the memory referenced by CS1's arguments. If not, return NoModRef.
   if (onlyAccessesArgPointees(CS1B)) {
     AliasAnalysis::ModRefResult R = NoModRef;
-    if (doesAccessArgPointees(CS1B))
+    if (doesAccessArgPointees(CS1B)) {
+      MDNode *CS1Tag = CS1.getInstruction()->getMetadata(LLVMContext::MD_tbaa);
       for (ImmutableCallSite::arg_iterator
-           I = CS1.arg_begin(), E = CS1.arg_end(); I != E; ++I)
-        if (getModRefInfo(CS2, *I, UnknownSize) != NoModRef) {
+           I = CS1.arg_begin(), E = CS1.arg_end(); I != E; ++I) {
+        const Value *Arg = *I;
+        if (!Arg->getType()->isPointerTy())
+          continue;
+        Location CS1Loc(Arg, UnknownSize, CS1Tag);
+        if (getModRefInfo(CS2, CS1Loc) != NoModRef) {
           R = Mask;
           break;
         }
+      }
+    }
     if (R == NoModRef)
       return R;
   }