[llvm-commits] [llvm] r41817 - /llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp

[Devang Patel]

Author: dpatel
Date: Mon Sep 10 18:34:06 2007
New Revision: 41817

URL: http://llvm.org/viewvc/llvm-project?rev=41817&view=rev
Log:
Swap exit condition operands if it works.

Modified:
    llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp?rev=41817&r1=41816&r2=41817&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp Mon Sep 10 18:34:06 2007
@@ -328,14 +328,24 @@
   if (!CI)
     return;
 
-  // FIXME 
+  // FIXME
+  if (CI->getPredicate() == ICmpInst::ICMP_EQ
+      || CI->getPredicate() == ICmpInst::ICMP_NE)
+    return;
+
   if (CI->getPredicate() == ICmpInst::ICMP_SGT
       || CI->getPredicate() == ICmpInst::ICMP_UGT
       || CI->getPredicate() == ICmpInst::ICMP_SGE
-      || CI->getPredicate() == ICmpInst::ICMP_UGE
-      || CI->getPredicate() == ICmpInst::ICMP_EQ
-      || CI->getPredicate() == ICmpInst::ICMP_NE)
-    return;
+      || CI->getPredicate() == ICmpInst::ICMP_UGE) {
+
+    BasicBlock *FirstSuccessor = BR->getSuccessor(0);
+    // splitLoop() is expecting LT/LE as exit condition predicate.
+    // Swap operands here if possible to meet this requirement.
+    if (!L->contains(FirstSuccessor)) 
+      CI->swapOperands();
+    else
+      return;
+  }
 
   ExitCondition = CI;