Integrate the readonly/readnone logic more deeply

into alias analysis.  This meant updating the API
which now has versions of the getModRefBehavior,
doesNotAccessMemory and onlyReadsMemory methods
which take a callsite parameter.  These should be
used unless the callsite is not known, since in
general they can do a better job than the versions
that take a function.  Also, users should no longer
call the version of getModRefBehavior that takes
both a function and a callsite.  To reduce the
chance of misuse it is now protected.

llvm-svn: 44487

1 files changed, 2 insertions, 3 deletions

diff --git a/llvm/lib/Analysis/LoadValueNumbering.cpp b/llvm/lib/Analysis/LoadValueNumbering.cpp
index 3af92bc11cb..67d4dd22bba 100644
--- a/llvm/lib/Analysis/LoadValueNumbering.cpp
+++ b/llvm/lib/Analysis/LoadValueNumbering.cpp
@@ -148,7 +148,7 @@ void LoadVN::getCallEqualNumberNodes(CallInst *CI,
   Function *CF = CI->getCalledFunction();
   if (CF == 0) return;  // Indirect call.
   AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
-  AliasAnalysis::ModRefBehavior MRB = AA.getModRefBehavior(CF, CI);
+  AliasAnalysis::ModRefBehavior MRB = AA.getModRefBehavior(CI);
   if (MRB != AliasAnalysis::DoesNotAccessMemory &&
       MRB != AliasAnalysis::OnlyReadsMemory)
     return;  // Nothing we can do for now.
@@ -227,8 +227,7 @@ void LoadVN::getCallEqualNumberNodes(CallInst *CI,
               CantEqual = true;
               break;
             } else if (CallInst *CI = dyn_cast<CallInst>(I)) {
-              if (CI->getCalledFunction() == 0 ||
-                  !AA.onlyReadsMemory(CI->getCalledFunction())) {
+              if (!AA.onlyReadsMemory(CI)) {
                 CantEqual = true;
                 break;
               }