[all-commits] [llvm/llvm-project] 80c351: [InstCombine] Transform to undef incorrect atomic ...

[serguei-katkov via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 80c351cdb6eaa1a243693d98f24b559fb69746ba
      https://github.com/llvm/llvm-project/commit/80c351cdb6eaa1a243693d98f24b559fb69746ba
  Author: Serguei Katkov <serguei.katkov at azul.com>
  Date:   2020-03-17 (Tue, 17 Mar 2020)

  Changed paths:
    M llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
    M llvm/test/Transforms/InstCombine/element-atomic-memintrins.ll

  Log Message:
  -----------
  [InstCombine] Transform to undef incorrect atomic unordered mem intrinsics

According to LangRef:
If len is not a positive integer multiple of element_size, then the behaviour of the intrinsic is undefined.

Add InstCombine rule to transform intrinsic to undef operation.

This is a follow-up for D76116.

Reviewers: reames
Reviewed By: reames
Subscribers: hiraditya, jfb, dantrushin, llvm-commits
Differential Revision: https://reviews.llvm.org/D76215