commit 317f054531c9f09c08825f5db0b522532d1595af
author Dan Gohman <gohman@apple.com> Sat Jun 27 22:58:27 2009 +0000
committer Dan Gohman <gohman@apple.com> Sat Jun 27 22:58:27 2009 +0000
tree 7e13908efe58c3e557c8ff47792c63049682e4d6
parent ffdcba3dbdc3d87ef95e309fc158ee08c0edd0ed

Don't try to split a loop when the controlling icmp instruction
doesn't have an IV-based operand. This fixes PR4471.

llvm-svn: 74399

llvm/lib/Transforms/Scalar/LoopIndexSplit.cpp

diff --git a/llvm/lib/Transforms/Scalar/LoopIndexSplit.cpp b/llvm/lib/Transforms/Scalar/LoopIndexSplit.cpp
index 6f7a7f8..ff0ec6d 100644
--- a/llvm/lib/Transforms/Scalar/LoopIndexSplit.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopIndexSplit.cpp
@@ -258,6 +258,9 @@
     IVExitValue = ExitCondition->getOperand(0);
   if (!L->isLoopInvariant(IVExitValue))
     return false;
+  if (!IVBasedValues.count(
+        ExitCondition->getOperand(IVExitValue == ExitCondition->getOperand(0))))
+    return false;
 
   // If start value is more then exit value where induction variable
   // increments by 1 then we are potentially dealing with an infinite loop.