[all-commits] [llvm/llvm-project] 6b9662: [GlobalISel] fix crash in narrowScalarExtract if D...

[Dominik Montada via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 6b96623dcb0cdb092eccf27b4d0fff25ed28f4b5
      https://github.com/llvm/llvm-project/commit/6b96623dcb0cdb092eccf27b4d0fff25ed28f4b5
  Author: Dominik Montada <dominik.montada at hightec-rt.com>
  Date:   2020-03-12 (Thu, 12 Mar 2020)

  Changed paths:
    M llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
    M llvm/unittests/CodeGen/GlobalISel/LegalizerHelperTest.cpp

  Log Message:
  -----------
  [GlobalISel] fix crash in narrowScalarExtract if DstRegs only has one register

Summary: When narrowing a scalar G_EXTRACT where the destination lines up perfectly with a single result of the emitted G_UNMERGE_VALUES a COPY should be emitted instead of unconditionally trying to emit a G_MERGE_VALUES.

Reviewers: arsenm, dsanders

Reviewed By: arsenm

Subscribers: wdng, rovka, hiraditya, volkan, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75743