GH #49: Run GVN again after InstCombine.

rust-lang · Jun 27, 2017 · c782feb · c782feb
1 parent 318ccee
commit c782feb
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/lib/Transforms/IPO/PassManagerBuilder.cpp b/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -342,6 +342,8 @@ void PassManagerBuilder::addFunctionSimplificationPasses(
  // Run instcombine after redundancy elimination to exploit opportunities
  // opened up by them.
  addInstructionCombiningPass(MPM);
+ if (OptLevel > 1)
+ MPM.add(createGVNPass(DisableGVNLoadPRE)); // Remove redundancies
  addExtensionsToPM(EP_Peephole, MPM);
  MPM.add(createJumpThreadingPass()); // Thread jumps
  MPM.add(createCorrelatedValuePropagationPass());