[llvm-commits] [llvm] r122740 - /llvm/trunk/include/llvm/Support/StandardPasses.h

[Chris Lattner]

Author: lattner
Date: Mon Jan  3 00:19:09 2011
New Revision: 122740

URL: http://llvm.org/viewvc/llvm-project?rev=122740&view=rev
Log:
Turn on earlycse by default.  This seems to be a small performance
improvement in the generated code, and speeds up 'opt -std-compile-opts'
compile time on 176.gcc from 24.84s to 23.2s (about 7%).

This also resolves a specific code quality issue in rdar://7352081 which
was generating poor code for:

int t(int a, int b) {
  if (a & b & 1)
    return a & b;
  return 3;
}


Modified:
    llvm/trunk/include/llvm/Support/StandardPasses.h

Modified: llvm/trunk/include/llvm/Support/StandardPasses.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/StandardPasses.h?rev=122740&r1=122739&r2=122740&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/StandardPasses.h (original)
+++ llvm/trunk/include/llvm/Support/StandardPasses.h Mon Jan  3 00:19:09 2011
@@ -129,9 +129,9 @@
     
     // Start of function pass.
     PM->add(createScalarReplAggregatesPass());  // Break up aggregate allocas
+    PM->add(createEarlyCSEPass());              // Catch trivial redundancies
     if (SimplifyLibCalls)
       PM->add(createSimplifyLibCallsPass());    // Library Call Optimizations
-    PM->add(createInstructionCombiningPass());  // Cleanup for scalarrepl.
     PM->add(createJumpThreadingPass());         // Thread jumps.
     PM->add(createCorrelatedValuePropagationPass()); // Propagate conditionals
     PM->add(createCFGSimplificationPass());     // Merge & remove BBs