[all-commits] [llvm/llvm-project] 016092: Reapply "[X86][AMX] Try to hoist AMX shapes' def"

[Pengfei Wang via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 016092d786f226f403fce5b5d0888dfa939b3f21
      https://github.com/llvm/llvm-project/commit/016092d786f226f403fce5b5d0888dfa939b3f21
  Author: Wang, Pengfei <pengfei.wang at intel.com>
  Date:   2021-04-27 (Tue, 27 Apr 2021)

  Changed paths:
    M llvm/lib/Target/X86/X86PreTileConfig.cpp
    M llvm/test/CodeGen/X86/AMX/amx-sched.ll

  Log Message:
  -----------
  Reapply "[X86][AMX] Try to hoist AMX shapes' def"

We request no intersections between AMX instructions and their shapes'
def when we insert ldtilecfg. However, this is not always ture resulting
from not only users don't follow AMX API model, but also optimizations.

This patch adds a mechanism that tries to hoist AMX shapes' def as well.
It only hoists shapes inside a BB, we can improve it for cases across
BBs in future. Currently, it only hoists shapes of which all sources' def
above the first AMX instruction. We can improve for the case that only
source that moves an immediate value to a register below AMX instruction.

Reviewed By: xiangzhangllvm

Differential Revision: https://reviews.llvm.org/D101067