[Bug target/112891] [10/11/12/13/14 Regression] Missing vzeroupper insert.

[liuhongt at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112891

--- Comment #3 from Hongtao Liu <liuhongt at gcc dot gnu.org> ---
(In reply to Hongtao Liu from comment #2)
> (In reply to Hongtao Liu from comment #1)
> > Aaused by r10-3477-g2a2e3a0dfcbe08, Can be fixed by revert the patch.
> > 
> > --- a/gcc/config/i386/i386.cc
> > +++ b/gcc/config/i386/i386.cc
> > @@ -15032,14 +15032,7 @@ ix86_avx_u128_mode_needed (rtx_insn *insn)
> >        if (avx_upper_reg_found)
> >         return AVX_U128_DIRTY;
> > 
> > -      /* If the function is known to preserve some SSE registers,
> > -        RA and previous passes can legitimately rely on that for
> > -        modes wider than 256 bits.  It's only safe to issue a
> > -        vzeroupper if all SSE registers are clobbered.  */
> > -      const function_abi &abi = insn_callee_abi (insn);
> > -      if (vzeroupper_pattern (PATTERN (insn), VOIDmode)
> > -         || !hard_reg_set_subset_p (reg_class_contents[SSE_REGS],
> > -                                    abi.mode_clobbers (V4DImode)))
> > +      if (vzeroupper_pattern (PATTERN (insn), VOIDmode))
> >         return AVX_U128_ANY;
> > 
> >        return AVX_U128_CLEAN;
> Remove this regressed many testcases
> 
> So it looks like we need to handle ix86_avx_u128_mode_after 
> 
> --- a/gcc/config/i386/i386.cc
> +++ b/gcc/config/i386/i386.cc
> @@ -15177,7 +15177,14 @@ ix86_avx_u128_mode_after (int mode, rtx_insn *insn)
>        bool avx_upper_reg_found = false;
>        note_stores (insn, ix86_check_avx_upper_stores, &avx_upper_reg_found);
> 
> -      return avx_upper_reg_found ? AVX_U128_DIRTY : AVX_U128_CLEAN;
> +      if (avx_upper_reg_found)
> +       return AVX_U128_DIRTY;
> +
> +      const function_abi &abi = insn_callee_abi (insn);
> +      if (!hard_reg_set_subset_p (reg_class_contents[SSE_REGS],
> +                                 abi.mode_clobbers (V4DImode)))
> +       return AVX_U128_ANY;
> +      return  AVX_U128_CLEAN;
>      }

Also for sibcall, we should return AVX_U128_CLEAN for
ix86_avx_u128_mode_needed.