[llvm-commits] [llvm] r80017 - /llvm/trunk/lib/Analysis/ScalarEvolution.cpp

[Dan Gohman]

Author: djg
Date: Tue Aug 25 12:56:57 2009
New Revision: 80017

URL: http://llvm.org/viewvc/llvm-project?rev=80017&view=rev
Log:
Don't assume that two identical instructions that read from memory
will always return the same value. This isn't currently necessary,
since this code doesn't currently ever get called under circumstances
where it would matter, but it may some day.

Modified:
    llvm/trunk/lib/Analysis/ScalarEvolution.cpp

Modified: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolution.cpp?rev=80017&r1=80016&r2=80017&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp Tue Aug 25 12:56:57 2009
@@ -4349,7 +4349,7 @@
     if (const SCEVUnknown *BU = dyn_cast<SCEVUnknown>(B))
       if (const Instruction *AI = dyn_cast<Instruction>(AU->getValue()))
         if (const Instruction *BI = dyn_cast<Instruction>(BU->getValue()))
-          if (AI->isIdenticalTo(BI))
+          if (AI->isIdenticalTo(BI) && !AI->mayReadFromMemory())
             return true;
 
   // Otherwise assume they may have a different value.