[PM] Add pgo-memop-opt pass to the new pass manager

[xur]

Summary

This pass adds pgo-memop-opt pass to the new pass manager.
It is in the old pass manager but somehow left out in the new pass manager.

[davide]

Is it expected that we run this pass in the default -O1/-O2 pipeline?
I thought this was enabled only when -fprofile-instr-{generate/use} is specified.

[davidxl]

lib/Passes/PassBuilder.cpp

365

check PGOOpt && !PGOOpt->ProfileUseFile.empty()

[xur]

Thanks for the review. Here is the updated patch.

[davide]

Don't we have a test for this? We should (I thought the PGO pipeline was tested, if it's not, you can probably add a test in a follow-up)

[davidxl]

lib/Passes/PassBuilder.cpp

366

Should checkProfileUseFile instead of SampleProfileFile.

[xur]

Updated the patch with review comments.

@davidxl: I meant to use PGOOpt->SampleProfileFile.empty(), instead of !PGOOpt->SampleProfileFile.empty().
But !PGOOpt->ProfileUseFile.empty() is definitely better here.

@davide: Added the check in PGO use pipeline.

Thanks!

[davide]

LGTM now, thanks.

[davide]

lib/Passes/PassBuilder.cpp

365

Bonus point if you add a comment :)

[davidxl]

lgtm

lib/Passes/PassBuilder.cpp

PassBuilder::buildFunctionSimplificationPipeline(OptimizationLevel Level,
   FPM.addPass(SimplifyCFGPass());
   FPM.addPass(InstCombinePass());
 
   if (!isOptimizingForSize(Level))
     FPM.addPass(LibCallsShrinkWrapPass());
 
   invokePeepholeEPCallbacks(FPM, Level);
 
+  if (PGOOpt && !isOptimizingForSize(Level) &&
+      !PGOOpt->SampleProfileFile.empty())
+    FPM.addPass(PGOMemOPSizeOpt());
+
   FPM.addPass(TailCallElimPass());
   FPM.addPass(SimplifyCFGPass());
 
   // Form canonically associated expression trees, and simplify the trees using
   // basic mathematical properties. For example, this will form (nearly)
   // minimal multiplication trees.
   FPM.addPass(ReassociatePass());