On Tue, Jan 9, 2024 at 3:09 PM Hongyu Wang <hongyu.w...@intel.com> wrote:
>
> Hi,
>
> For APX, the inline asm behavior was not mentioned in any document
> before. Add description for it.
>
> Ok for trunk?
>
> gcc/ChangeLog:
>
> * config/i386/i386.opt: Adjust document.
> * doc/invoke.texi: Add description for
> -mapx-inline-asm-use-gpr32.
> ---
> gcc/config/i386/i386.opt | 3 +--
> gcc/doc/invoke.texi | 7 +++++++
> 2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/gcc/config/i386/i386.opt b/gcc/config/i386/i386.opt
> index a38e92baf92..5b4f1bff25f 100644
> --- a/gcc/config/i386/i386.opt
> +++ b/gcc/config/i386/i386.opt
> @@ -1357,8 +1357,7 @@ Enum(apx_features) String(all) Value(apx_all) Set(1)
>
> mapx-inline-asm-use-gpr32
> Target Var(ix86_apx_inline_asm_use_gpr32) Init(0)
> -Enable GPR32 in inline asm when APX_EGPR enabled, do not
> -hook reg or mem constraint in inline asm to GPR16.
> +Enable GPR32 in inline asm when APX_F enabled.
>
> mevex512
> Target Mask(ISA2_EVEX512) Var(ix86_isa_flags2) Save
> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
> index 68d1f364ac0..47fd96648d8 100644
> --- a/gcc/doc/invoke.texi
> +++ b/gcc/doc/invoke.texi
> @@ -35272,6 +35272,13 @@ r8-r15 registers so that the call and jmp
> instruction length is 6 bytes
> to allow them to be replaced with @samp{lfence; call *%r8-r15} or
> @samp{lfence; jmp *%r8-r15} at run-time.
>
> +@opindex mapx-inline-asm-use-gpr32
> +@item -mapx-inline-asm-use-gpr32
> +When APX_F enabled, EGPR usage was by default disabled to prevent
> +unexpected EGPR generation in instructions that does not support it.
> +To invoke EGPR usage in inline asm, use this switch to allow EGPR in
> +inline asm, while user should ensure the asm actually supports EGPR.
Please align with
https://gcc.gnu.org/pipermail/gcc-patches/2024-January/642228.html.
Ok after changing that.
> +
> @end table
>
> These @samp{-m} switches are supported in addition to the above
> --
> 2.31.1
>
--
BR,
Hongtao
