[llvm-commits] CVS: llvm/lib/Transforms/Utils/Local.cpp

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Utils:

Local.cpp updated: 1.34 -> 1.35
---
Log message:

Enhance hasConstantValue to ignore undef values in phi nodes.  This allows it
to think that PHI[4, undef] == 4.



---
Diffs of the changes:  (+3 -2)

Index: llvm/lib/Transforms/Utils/Local.cpp
diff -u llvm/lib/Transforms/Utils/Local.cpp:1.34 llvm/lib/Transforms/Utils/Local.cpp:1.35
--- llvm/lib/Transforms/Utils/Local.cpp:1.34	Wed Sep  1 17:55:36 2004
+++ llvm/lib/Transforms/Utils/Local.cpp	Sun Oct 17 16:23:26 2004
@@ -353,7 +353,8 @@
   //
   Value *InVal = 0;
   for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
-    if (PN->getIncomingValue(i) != PN)  // Not the PHI node itself...
+    if (PN->getIncomingValue(i) != PN &&  // Not the PHI node itself...
+        !isa<UndefValue>(PN->getIncomingValue(i)))
       if (InVal && PN->getIncomingValue(i) != InVal)
         return 0;  // Not the same, bail out.
       else
@@ -363,7 +364,7 @@
   // that only has entries for itself.  In this case, there is no entry into the
   // loop, so kill the PHI.
   //
-  if (InVal == 0) InVal = Constant::getNullValue(PN->getType());
+  if (InVal == 0) InVal = UndefValue::get(PN->getType());
 
   // All of the incoming values are the same, return the value now.
   return InVal;