[llvm-commits] [llvm] r122600 - /llvm/trunk/include/llvm/Analysis/LoopInfo.h

[Duncan Sands]

Author: baldrick
Date: Tue Dec 28 12:00:24 2010
New Revision: 122600

URL: http://llvm.org/viewvc/llvm-project?rev=122600&view=rev
Log:
Small optimization to speed up replacementPreservesLCSSAForm.

Modified:
    llvm/trunk/include/llvm/Analysis/LoopInfo.h

Modified: llvm/trunk/include/llvm/Analysis/LoopInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/LoopInfo.h?rev=122600&r1=122599&r2=122600&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/LoopInfo.h (original)
+++ llvm/trunk/include/llvm/Analysis/LoopInfo.h Tue Dec 28 12:00:24 2010
@@ -1029,6 +1029,10 @@
     // instruction.
     Instruction *I = dyn_cast<Instruction>(To);
     if (!I) return true;
+    // If both instructions are defined in the same basic block then replacement
+    // cannot break LCSSA form.
+    if (I->getParent() == From->getParent())
+      return true;
     // If the instruction is not defined in a loop then it can safely replace
     // anything.
     Loop *ToLoop = getLoopFor(I->getParent());