[all-commits] [llvm/llvm-project] 3a5adf: [ARM] Add MVE insert-of-extract pattern

[David Green via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 3a5adf84834a2b6fad57214278e4ec743977356c
      https://github.com/llvm/llvm-project/commit/3a5adf84834a2b6fad57214278e4ec743977356c
  Author: David Green <david.green at arm.com>
  Date:   2021-02-02 (Tue, 02 Feb 2021)

  Changed paths:
    M llvm/lib/Target/ARM/ARMInstrMVE.td
    M llvm/test/CodeGen/Thumb2/mve-vecreduce-add.ll

  Log Message:
  -----------
  [ARM] Add MVE insert-of-extract pattern

A v4i32 insert of an extract can become a simple lane move, as opposed
to round-tripping via a GPR. This adds a patterns that turns an v4i32
insert-extract pair into a EXTRACT_SUBREG/INSERT_SUBREG, with the
required COPY_TO_REGCLASS. These get better optimized into a simple lane
move by the rest of the backend.

Differential Revision: https://reviews.llvm.org/D95428