[llvm-commits] [llvm] r118627 - in /llvm/trunk: lib/Transforms/IPO/FunctionAttrs.cpp test/Analysis/TypeBasedAliasAnalysis/functionattrs.ll

[Dan Gohman]

Author: djg
Date: Tue Nov  9 14:17:38 2010
New Revision: 118627

URL: http://llvm.org/viewvc/llvm-project?rev=118627&view=rev
Log:
Teach FunctionAttrs about the VAArg instruction.

Modified:
    llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp
    llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/functionattrs.ll

Modified: llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp?rev=118627&r1=118626&r2=118627&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp Tue Nov  9 14:17:38 2010
@@ -195,6 +195,13 @@
           if (AA->pointsToConstantMemory(Loc, /*OrLocal=*/true))
             continue;
         }
+      } else if (VAArgInst *VI = dyn_cast<VAArgInst>(I)) {
+        // Ignore vaargs on local memory.
+        AliasAnalysis::Location Loc(VI->getPointerOperand(),
+                                    AliasAnalysis::UnknownSize,
+                                    VI->getMetadata(LLVMContext::MD_tbaa));
+        if (AA->pointsToConstantMemory(Loc, /*OrLocal=*/true))
+          continue;
       }
 
       // Any remaining instructions need to be taken seriously!  Check if they

Modified: llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/functionattrs.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/functionattrs.ll?rev=118627&r1=118626&r2=118627&view=diff
==============================================================================
--- llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/functionattrs.ll (original)
+++ llvm/trunk/test/Analysis/TypeBasedAliasAnalysis/functionattrs.ll Tue Nov  9 14:17:38 2010
@@ -55,6 +55,20 @@
   ret void
 }
 
+; Similar to the others, va_arg only accesses memory through its operand.
+
+; CHECK: define i32 @test3_yes(i8* nocapture %p) nounwind readnone {
+define i32 @test3_yes(i8* %p) nounwind {
+  %t = va_arg i8* %p, i32, !tbaa !1
+  ret i32 %t
+}
+
+; CHECK: define i32 @test3_no(i8* nocapture %p) nounwind {
+define i32 @test3_no(i8* %p) nounwind {
+  %t = va_arg i8* %p, i32, !tbaa !2
+  ret i32 %t
+}
+
 declare void @callee(i32* %p) nounwind
 declare void @llvm.memcpy.p0i8.p0i8.i64(i8*, i8*, i64, i32, i1) nounwind