[llvm-commits] [llvm] r99699 - /llvm/trunk/lib/Transforms/IPO/ArgumentPromotion.cpp

[Eric Christopher]

Author: echristo
Date: Fri Mar 26 20:54:00 2010
New Revision: 99699

URL: http://llvm.org/viewvc/llvm-project?rev=99699&view=rev
Log:
When we promote a load of an argument make sure to take the alignment
of the previous load - it's usually important.  For example, we don't want
to blindly turn an unaligned load into an aligned one.

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

Modified: llvm/trunk/lib/Transforms/IPO/ArgumentPromotion.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/ArgumentPromotion.cpp?rev=99699&r1=99698&r2=99699&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/ArgumentPromotion.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/ArgumentPromotion.cpp Fri Mar 26 20:54:00 2010
@@ -687,7 +687,11 @@
             Ops.clear();
             AA.copyValue(OrigLoad->getOperand(0), V);
           }
-          Args.push_back(new LoadInst(V, V->getName()+".val", Call));
+          // Since we're replacing a load make sure we take the alignment
+          // of the previous load.
+          LoadInst *newLoad = new LoadInst(V, V->getName()+".val", Call);
+          newLoad->setAlignment(OrigLoad->getAlignment());
+          Args.push_back(newLoad);
           AA.copyValue(OrigLoad, Args.back());
         }
       }