[all-commits] [llvm/llvm-project] 0a3716: [GlobalISel] Add scalar widening for G_MERGE_VALUE...

[Jessica Paquette via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 0a37163d1d855a2db41e1f46ddbc3f4570bd7ca6
      https://github.com/llvm/llvm-project/commit/0a37163d1d855a2db41e1f46ddbc3f4570bd7ca6
  Author: Jessica Paquette <jpaquette at apple.com>
  Date:   2021-07-26 (Mon, 26 Jul 2021)

  Changed paths:
    M llvm/include/llvm/CodeGen/GlobalISel/LegalizerHelper.h
    M llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp
    M llvm/test/CodeGen/AArch64/GlobalISel/legalize-merge-values.mir

  Log Message:
  -----------
  [GlobalISel] Add scalar widening for G_MERGE_VALUES destination

This adds support for the case where

WideSize = DstSize + K * SrcSize

In this case, we can pad the G_MERGE_VALUES instruction with K extra undef
values with width SrcSize. Then the destination can be handled via
widenScalarDst.

Differential Revision: https://reviews.llvm.org/D106814