[llvm] r173730 - Unroll again after running BBVectorize

[Hal Finkel]

Author: hfinkel
Date: Mon Jan 28 18:22:49 2013
New Revision: 173730

URL: http://llvm.org/viewvc/llvm-project?rev=173730&view=rev
Log:
Unroll again after running BBVectorize

Because BBVectorize may significantly shorten a loop body, unroll
again after vectorization. This is especially important when using
runtime or partial unrolling.

Modified:
    llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp

Modified: llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp?rev=173730&r1=173729&r2=173730&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp Mon Jan 28 18:22:49 2013
@@ -214,6 +214,10 @@ void PassManagerBuilder::populateModuleP
       MPM.add(createGVNPass());                   // Remove redundancies
     else
       MPM.add(createEarlyCSEPass());              // Catch trivial redundancies
+
+    // BBVectorize may have significantly shortened a loop body; unroll again.
+    if (!DisableUnrollLoops)
+      MPM.add(createLoopUnrollPass());
   }
 
   MPM.add(createAggressiveDCEPass());         // Delete dead instructions