[all-commits] [llvm/llvm-project] 907871: [llvm] [CodeGen] Fixed vector halving bug for mask...

[Aart Bik via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 907871d9ad2dfc5bc96fb49e897aa68c45f32e80
      https://github.com/llvm/llvm-project/commit/907871d9ad2dfc5bc96fb49e897aa68c45f32e80
  Author: aartbik <ajcbik at google.com>
  Date:   2020-04-23 (Thu, 23 Apr 2020)

  Changed paths:
    M llvm/include/llvm/CodeGen/SelectionDAG.h
    M llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
    M llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
    A llvm/test/CodeGen/X86/pr45563-2.ll

  Log Message:
  -----------
  [llvm] [CodeGen] Fixed vector halving bug for masked load

Summary:
Given a VL=14 that is enveloped by a proper VL=16, splitting the
masked load using the enveloping halving VL=8/8 should yields
should eventually yield V=8/5. This fixes various assert failures
in getHalfNumVectorElementsVT() and IncrementMemoryAddress().

Note, I suspect similar fixes will be needed for other masked
operations, but for now I send out a fix for masked load only.

Bugzilla issue 45563
https://bugs.llvm.org/show_bug.cgi?id=45563

Reviewers: craig.topper, mehdi_amini, nicolasvasilache

Reviewed By: craig.topper

Subscribers: hiraditya, dmgreen, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78608