[PATCH] x86: Remove "%!" before ret

Uros Bizjak ubizjak@gmail.com
Wed Nov 17 19:46:12 GMT 2021


On Wed, Nov 17, 2021 at 8:44 PM H.J. Lu <hjl.tools@gmail.com> wrote:
>
> Before MPX was removed, "%!" was mapped to
>
>         case '!':
>           if (ix86_bnd_prefixed_insn_p (current_output_insn))
>             fputs ("bnd ", file);
>           return;
>
> After CET was added and MPX was removed, "%!" was mapped to
>
>        case '!':
>           if (ix86_notrack_prefixed_insn_p (current_output_insn))
>             fputs ("notrack ", file);
>           return;
>
> ix86_notrack_prefixed_insn_p always returns false on ret since the
> notrack prefix is only for indirect branches.  Remove the unused "%!"
> before ret.
>
>         PR target/103307
>         * config/i386/i386.c (ix86_code_end): Remove "%!" before ret.
>         (ix86_output_function_return): Likewise.
>         * config/i386/i386.md (simple_return_pop_internal): Likewise.
> ---
>  gcc/config/i386/i386.c  | 4 ++--
>  gcc/config/i386/i386.md | 2 +-
>  2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> index 73c4d5115bb..95d238e9efc 100644
> --- a/gcc/config/i386/i386.c
> +++ b/gcc/config/i386/i386.c
> @@ -6116,7 +6116,7 @@ ix86_code_end (void)
>        xops[0] = gen_rtx_REG (Pmode, regno);
>        xops[1] = gen_rtx_MEM (Pmode, stack_pointer_rtx);
>        output_asm_insn ("mov%z0\t{%1, %0|%0, %1}", xops);
> -      output_asm_insn ("%!ret", NULL);
> +      output_asm_insn ("ret", NULL);

This can use fputs.

Uros.

>        final_end_function ();
>        init_insn_lengths ();
>        free_after_compilation (cfun);
> @@ -16278,7 +16278,7 @@ ix86_output_function_return (bool long_p)
>      }
>
>    if (!long_p)
> -    return "%!ret";
> +    return "ret";
>
>    return "rep%; ret";
>  }
> diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
> index 73d15de88b2..7b2de60706d 100644
> --- a/gcc/config/i386/i386.md
> +++ b/gcc/config/i386/i386.md
> @@ -14705,7 +14705,7 @@ (define_insn_and_split "simple_return_pop_internal"
>    [(simple_return)
>     (use (match_operand:SI 0 "const_int_operand"))]
>    "reload_completed"
> -  "%!ret\t%0"
> +  "ret\t%0"
>    "&& cfun->machine->function_return_type != indirect_branch_keep"
>    [(const_int 0)]
>    "ix86_split_simple_return_pop_internal (operands[0]); DONE;"
> --
> 2.33.1
>


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