Fix for 2005-08-12-rlwimi-crash.ll.  Make allowance for masks being shifted to
zero.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22773 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelPattern.cpp b/lib/Target/PowerPC/PPCISelPattern.cpp
index 500333f..9725c2c 100644
--- a/lib/Target/PowerPC/PPCISelPattern.cpp
+++ b/lib/Target/PowerPC/PPCISelPattern.cpp
@@ -640,7 +640,7 @@
   }
   
   // if the mask doesn't intersect any Indeterminant bits
-  if (!(Mask & Indeterminant)) {
+  if (Mask && !(Mask & Indeterminant)) {
     SH = Shift;
     // make sure the mask is still a mask (wrap arounds may not be)
     return isRunOfOnes(Mask, MB, ME);