[all-commits] [llvm/llvm-project] bcdd40: [AsmParser][SystemZ][z/OS] Introducing HLASM Comme...

[Kai Nacke via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: bcdd40f802a5dfd7b3ac11304e6099bfcdd25b1e
      https://github.com/llvm/llvm-project/commit/bcdd40f802a5dfd7b3ac11304e6099bfcdd25b1e
  Author: Anirudh Prasad <Anirudh.Prasad at ibm.com>
  Date:   2021-03-12 (Fri, 12 Mar 2021)

  Changed paths:
    M llvm/include/llvm/MC/MCAsmInfo.h
    M llvm/lib/MC/MCParser/AsmLexer.cpp
    M llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmInfo.cpp
    A llvm/unittests/MC/SystemZ/CMakeLists.txt
    A llvm/unittests/MC/SystemZ/SystemZAsmLexerTest.cpp

  Log Message:
  -----------
  [AsmParser][SystemZ][z/OS] Introducing HLASM Comment Syntax

- This patch adds in support for the ordinary HLASM comment syntax asm
  statements (Reference - Chapter 7, Comment Statements, Ordinary Comment
  Statements)
- In brief, the ordinary comment syntax if used, must begin with the "*"
  character
- To achieve this, this patch makes use of the CommentString attribute
  provided in the base MCAsmInfo class
- In the SystemZMCAsmInfo class, the CommentString attribute was set to
  "*" based on the assembler dialect
- Furthermore, a new attribute RestrictCommentString, is provided to only
  treat a string as a comment if it appears at the start of the asm
  statement. Example: "jo *-4" is valid in HLASM (jump back 4 bytes from
  current point - similar to jo -4 in gnu asm) and we don't want "*-4" to
  be treated as a comment.
- RFC for HLASM Parser support implementation: https://lists.llvm.org/pipermail/llvm-dev/2021-January/147686.html

Reviewed By: scott.linder, Kai

Differential Revision: https://reviews.llvm.org/D97703