Make ModRefBehavior a lattice. Use this to clean up AliasAnalysis
chaining and simplify FunctionAttrs' GetModRefBehavior logic.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118660 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/IPA/GlobalsModRef.cpp b/lib/Analysis/IPA/GlobalsModRef.cpp
index 6e4fff7..456a80a 100644
--- a/lib/Analysis/IPA/GlobalsModRef.cpp
+++ b/lib/Analysis/IPA/GlobalsModRef.cpp
@@ -120,28 +120,33 @@
/// called from the specified call site. The call site may be null in which
/// case the most generic behavior of this function should be returned.
ModRefBehavior getModRefBehavior(const Function *F) {
+ ModRefBehavior Min = UnknownModRefBehavior;
+
if (FunctionRecord *FR = getFunctionInfo(F)) {
if (FR->FunctionEffect == 0)
- return DoesNotAccessMemory;
+ Min = DoesNotAccessMemory;
else if ((FR->FunctionEffect & Mod) == 0)
- return OnlyReadsMemory;
+ Min = OnlyReadsMemory;
}
- return AliasAnalysis::getModRefBehavior(F);
+
+ return ModRefBehavior(AliasAnalysis::getModRefBehavior(F) & Min);
}
/// getModRefBehavior - Return the behavior of the specified function if
/// called from the specified call site. The call site may be null in which
/// case the most generic behavior of this function should be returned.
ModRefBehavior getModRefBehavior(ImmutableCallSite CS) {
- const Function* F = CS.getCalledFunction();
- if (!F) return AliasAnalysis::getModRefBehavior(CS);
- if (FunctionRecord *FR = getFunctionInfo(F)) {
- if (FR->FunctionEffect == 0)
- return DoesNotAccessMemory;
- else if ((FR->FunctionEffect & Mod) == 0)
- return OnlyReadsMemory;
- }
- return AliasAnalysis::getModRefBehavior(CS);
+ ModRefBehavior Min = UnknownModRefBehavior;
+
+ if (const Function* F = CS.getCalledFunction())
+ if (FunctionRecord *FR = getFunctionInfo(F)) {
+ if (FR->FunctionEffect == 0)
+ Min = DoesNotAccessMemory;
+ else if ((FR->FunctionEffect & Mod) == 0)
+ Min = OnlyReadsMemory;
+ }
+
+ return ModRefBehavior(AliasAnalysis::getModRefBehavior(CS) & Min);
}
virtual void deleteValue(Value *V);