[all-commits] [llvm/llvm-project] 5ea357: [AArch64] Split out processor/tuning features

[david-arm via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 5ea35791e6642f6160819c930f79b0f57ad0e907
      https://github.com/llvm/llvm-project/commit/5ea35791e6642f6160819c930f79b0f57ad0e907
  Author: David Sherwood <david.sherwood at arm.com>
  Date:   2021-10-19 (Tue, 19 Oct 2021)

  Changed paths:
    M llvm/lib/Target/AArch64/AArch64.td
    M llvm/lib/Target/AArch64/AArch64Subtarget.h
    M llvm/lib/Target/AArch64/AArch64SystemOperands.td
    A llvm/test/CodeGen/AArch64/misched-fusion-addr-tune.ll

  Log Message:
  -----------
  [AArch64] Split out processor/tuning features

Following on from an earlier patch that introduced support for -mtune
for AArch64 backends, this patch splits out the tuning features
from the processor features. This gives us the ability to enable
architectural feature set A for a given processor with "-mcpu=A"
and define the set of tuning features B with "-mtune=B".

It's quite difficult to write a test that proves we select the
right features according to the tuning attribute because most
of these relate to scheduling. I have created a test here:

  CodeGen/AArch64/misched-fusion-addr-tune.ll

that demonstrates the different scheduling choices based upon
the tuning.

Differential Revision: https://reviews.llvm.org/D111551