[all-commits] [llvm/llvm-project] cb7fb7: [AArch64] Assembly Support for FEAT_GCS/FEAT_CHK

[Sam Elliott via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: cb7fb737858cdfdc90406f9675c8470ea98417ed
      https://github.com/llvm/llvm-project/commit/cb7fb737858cdfdc90406f9675c8470ea98417ed
  Author: Archibald Elliott <archibald.elliott at arm.com>
  Date:   2023-03-15 (Wed, 15 Mar 2023)

  Changed paths:
    M clang/lib/Basic/Targets/AArch64.cpp
    M clang/lib/Basic/Targets/AArch64.h
    M llvm/include/llvm/TargetParser/AArch64TargetParser.h
    M llvm/lib/Target/AArch64/AArch64.td
    M llvm/lib/Target/AArch64/AArch64InstrInfo.td
    M llvm/lib/Target/AArch64/AArch64SystemOperands.td
    M llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp
    A llvm/test/MC/AArch64/armv9.4a-chk.s
    A llvm/test/MC/AArch64/armv9.4a-gcs.s
    M llvm/test/MC/AArch64/directive-arch_extension-negative.s
    M llvm/test/MC/AArch64/directive-arch_extension.s
    A llvm/test/MC/Disassembler/AArch64/armv9.4a-chk.txt
    A llvm/test/MC/Disassembler/AArch64/armv9.4a-gcs.txt
    M llvm/unittests/TargetParser/TargetParserTest.cpp

  Log Message:
  -----------
  [AArch64] Assembly Support for FEAT_GCS/FEAT_CHK

This implements support for two new 2022 A-profile extensions:
- FEAT_CHK - Check Feature Status Extension
- FEAT_GCS - Guarded Control Stacks

FEAT_CHK is mandatory from armv8.0-a, but is in the hint space so
there's no clang command-line flag for it, and we only print the hint as
`chkfeat x16` at v8.9a and above, to be compatible when using a
non-integrated assembler that might not yet know about the extension.

FEAT_GCS is optional from armv9.4-a onwards. It is enabled using `+gcs`
in a clang `-march=` or `-mcpu=` option string, or using a
`.arch_extension gcs` assembly directive.

This patch includes changes by Ties Stuij, Tomas Matheson, and Keith
Walker.

Differential Revision: https://reviews.llvm.org/D145563