[llvm-commits] [llvm] r81164 - /llvm/trunk/lib/Transforms/IPO/GlobalOpt.cpp

[Dan Gohman]

Author: djg
Date: Mon Sep  7 17:42:05 2009
New Revision: 81164

URL: http://llvm.org/viewvc/llvm-project?rev=81164&view=rev
Log:
Don't commit addresses of aggregate values. This avoids problems with
an aggregate store overlapping a different aggregate store, despite
the stores having distinct addresses.

Modified:
    llvm/trunk/lib/Transforms/IPO/GlobalOpt.cpp

Modified: llvm/trunk/lib/Transforms/IPO/GlobalOpt.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/GlobalOpt.cpp?rev=81164&r1=81163&r2=81164&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/IPO/GlobalOpt.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/GlobalOpt.cpp Mon Sep  7 17:42:05 2009
@@ -2024,6 +2024,11 @@
 /// we punt.  We basically just support direct accesses to globals and GEP's of
 /// globals.  This should be kept up to date with CommitValueTo.
 static bool isSimpleEnoughPointerToCommit(Constant *C, LLVMContext &Context) {
+  // Conservatively, avoid aggregate types. This is because we don't
+  // want to worry about them partially overlapping other stores.
+  if (!cast<PointerType>(C->getType())->getElementType()->isSingleValueType())
+    return false;
+
   if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C))
     // Do not allow weak/linkonce/dllimport/dllexport linkage or
     // external globals.