Add instcombine after global optimizations.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51611 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/lto2/LTOCodeGenerator.cpp b/tools/lto2/LTOCodeGenerator.cpp
index ae97694..13ba0db 100644
--- a/tools/lto2/LTOCodeGenerator.cpp
+++ b/tools/lto2/LTOCodeGenerator.cpp
@@ -360,6 +360,12 @@
     // Remove unused arguments from functions...
     passes.add(createDeadArgEliminationPass());
 
+    // Reduce the code after globalopt and ipsccp.  Both can open up significant
+    // simplification opportunities, and both can propagate functions through
+    // function pointers.  When this happens, we often have to resolve varargs
+    // calls, etc, so let instcombine do this.
+    passes.add(createInstructionCombiningPass());
+
     passes.add(createFunctionInliningPass()); // Inline small functions
 
     passes.add(createPruneEHPass());            // Remove dead EH info