[all-commits] [llvm/llvm-project] 2e9a04: [X86]Add NO_REVERSE attribute to X86 RMW instrs in...

[XinWang10 via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 2e9a04b985e856c5ba4ec60951ebe4c3590d187f
      https://github.com/llvm/llvm-project/commit/2e9a04b985e856c5ba4ec60951ebe4c3590d187f
  Author: XinWang10 <108658776+XinWang10 at users.noreply.github.com>
  Date:   2023-09-27 (Wed, 27 Sep 2023)

  Changed paths:
    M llvm/test/TableGen/x86-fold-tables.inc
    M llvm/utils/TableGen/X86FoldTablesEmitter.cpp

  Log Message:
  -----------
  [X86]Add NO_REVERSE attribute to X86 RMW instrs in memfold table (#67288)

X86 don't want to unfold RMW instrs to 1 load + 1 op + 1 store, because
RMW could save code size and benefit RA when reg pressure is high.
And from all the call position analysis, we could find we didn't unfold
RMW in current code.