[llvm] r244622 - Enable EliminateAvailableExternally pass in the LTO pipeline.

[Teresa Johnson via llvm-commits]

Author: tejohnson
Date: Tue Aug 11 11:26:41 2015
New Revision: 244622

URL: http://llvm.org/viewvc/llvm-project?rev=244622&view=rev
Log:
Enable EliminateAvailableExternally pass in the LTO pipeline.

Summary:
For LTO we need to enable this pass in the LTO pipeline,
as it is skipped during the "-flto -c" compile step (when PrepareForLTO is
set).

Reviewers: rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D11919

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=244622&r1=244621&r2=244622&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/PassManagerBuilder.cpp Tue Aug 11 11:26:41 2015
@@ -556,6 +556,9 @@ void PassManagerBuilder::addLateLTOOptim
   // Delete basic blocks, which optimization passes may have killed.
   PM.add(createCFGSimplificationPass());
 
+  // Drop bodies of available externally objects to improve GlobalDCE.
+  PM.add(createEliminateAvailableExternallyPass());
+
   // Now that we have optimized the program, discard unreachable functions.
   PM.add(createGlobalDCEPass());