tree 19ae40b36b5e73db9d41bc27c8aa6bdf1ddadd2f
parent e3707b846d4b72f4199b35e43b6e1d543f7f93ae
author Nirav Dave <niravd@google.com> 1552496829 +0000
committer Nirav Dave <niravd@google.com> 1552496829 +0000

[DAGCombiner] If a TokenFactor would be merged into its user, consider the user later.

Summary:
A number of optimizations are inhibited by single-use TokenFactors not
being merged into the TokenFactor using it. This makes we consider if
we can do the merge immediately.

Most tests changes here are due to the change in visitation causing
minor reorderings and associated reassociation of paired memory
operations.

CodeGen tests with non-reordering changes:

  X86/aligned-variadic.ll -- memory-based add folded into stored leaq
  value.

  X86/constant-combiners.ll -- Optimizes out overlap between stores.

  X86/pr40631_deadstore_elision -- folds constant byte store into
  preceding quad word constant store.

Reviewers: RKSimon, craig.topper, spatel, efriedma, courbet

Reviewed By: courbet

Subscribers: dylanmckay, sdardis, nemanjai, jvesely, nhaehnle, javed.absar, eraman, hiraditya, kbarton, jrtc27, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59260

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356068 91177308-0d34-0410-b5e6-96231b3b80d8