[all-commits] [llvm/llvm-project] 482283: [AArch64] Remove custom zext/sext legalization code.

[Florian Hahn via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 482283042f795ecc27838a3b2f76b5494991401c
      https://github.com/llvm/llvm-project/commit/482283042f795ecc27838a3b2f76b5494991401c
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2021-03-29 (Mon, 29 Mar 2021)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
    M llvm/test/CodeGen/AArch64/arm64-subvector-extend.ll

  Log Message:
  -----------
  [AArch64] Remove custom zext/sext legalization code.

Currently performExtendCombine assumes that the src-element bitwidth * 2
is a valid MVT. But this is not the case for i1 and it causes a crash on
the v64i1 test cases added in this patch.

It turns out that this code appears to not be needed; the same patterns are
handled by other code and we end up with the same results, even without the
custom lowering. I also added additional test cases in a50037aaa6d5df.

Let's just remove the unneeded code.

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D99437