[llvm-commits] CVS: llvm/lib/Transforms/Scalar/InstructionCombining.cpp

[Chris Lattner]

Changes in directory llvm/lib/Transforms/Scalar:

InstructionCombining.cpp updated: 1.602 -> 1.603
---
Log message:

Fix InstCombine/2007-01-18-VectorInfLoop.ll, a case where instcombine
infinitely loops.


---
Diffs of the changes:  (+9 -3)

 InstructionCombining.cpp |   12 +++++++++---
 1 files changed, 9 insertions(+), 3 deletions(-)


Index: llvm/lib/Transforms/Scalar/InstructionCombining.cpp
diff -u llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.602 llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.603
--- llvm/lib/Transforms/Scalar/InstructionCombining.cpp:1.602	Thu Jan 18 12:54:33 2007
+++ llvm/lib/Transforms/Scalar/InstructionCombining.cpp	Thu Jan 18 16:16:33 2007
@@ -3062,10 +3062,16 @@
   // See if we can simplify any instructions used by the instruction whose sole 
   // purpose is to compute bits we don't care about.
   uint64_t KnownZero, KnownOne;
-  if (!isa<PackedType>(I.getType()) &&
-      SimplifyDemandedBits(&I, I.getType()->getIntegerTypeMask(),
-                           KnownZero, KnownOne))
+  if (!isa<PackedType>(I.getType())) {
+    if (SimplifyDemandedBits(&I, I.getType()->getIntegerTypeMask(),
+                             KnownZero, KnownOne))
     return &I;
+  } else {
+    if (ConstantPacked *CP = dyn_cast<ConstantPacked>(Op1)) {
+      if (CP->isAllOnesValue())
+        return ReplaceInstUsesWith(I, I.getOperand(0));
+    }
+  }
   
   if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(Op1)) {
     uint64_t AndRHSMask = AndRHS->getZExtValue();