Run another local value numbering phase after redundancy elimination


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2625 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/gccas/gccas.cpp b/tools/gccas/gccas.cpp
index c2f7a8c..1a0067e 100644
--- a/tools/gccas/gccas.cpp
+++ b/tools/gccas/gccas.cpp
@@ -83,6 +83,10 @@
     Passes.add(createLICMPass());                   // Hoist loop invariants
     Passes.add(createGCSEPass());                   // Remove common subexprs
     Passes.add(createSCCPPass());                   // Constant prop with SCCP
+
+    // Run instcombine after redundancy elimination to exploit opportunities
+    // opened up by them.
+    Passes.add(createInstructionCombiningPass());
     Passes.add(createDeadCodeEliminationPass());    // Remove Dead code/vars
   }
   Passes.add(new WriteBytecodePass(&Out));        // Write bytecode to file...