On Thu, Jan 11, 2024 at 7:06 AM Andi Kleen <a...@linux.intel.com> wrote: > > Hongtao Liu <crazy...@gmail.com> writes: > >> > >> +@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. > > BTW I think we would need a way to specify this individually per inline > asm statement too. > > Otherwise a library which wants to use APX inline asm in the header > never can do so until all its users set the option, which will be > awkward to deploy. > > Perhaps it could be a magic clobber string. We do have new constraints string for gpr32 or gpr16 for registers, but not for memory due to restrictiction of GCC RA infrastructure which assumes universal BASE_REG_CLASS/INDEX_REG_CLASS for all inline asm. > > -andi
-- BR, Hongtao