Re: [PATCH 08/13] [APX EGPR] Handle GPR16 only vector move insns
On Fri, Sep 01, 2023 at 07:34:16PM +0800, Hongyu Wang wrote:
> > On Fri, Sep 01, 2023 at 05:07:53PM +0800, Hongyu Wang wrote:
> > > Jakub Jelinek via Gcc-patches 于2023年8月31日周四
> > > 17:44写道：
> > > >
> > > > On Thu, Aug 31, 2023 at 04:20:19PM +0800, Hongyu Wang via Gcc-patches
> > > > wrote:
> > > > > For vector move insns like vmovdqa/vmovdqu, their evex counterparts
> > > > > requrire explicit suffix 64/32/16/8. The usage of these instruction
> > > > > are prohibited under AVX10_1 or AVX512F, so for AVX2+APX_F we select
> > > > > vmovaps/vmovups for vector load/store insns that contains EGPR.
> > > >
> > > > Why not make it dependent on AVX512VL?
> > > > I.e. if egpr_p && TARGET_AVX512VL, still use vmovdqu16 or vmovdqa16
> > > > and the like, and only if !evex_reg_p && egpr_p && !TARGET_AVX512VL
> > > > fall back to what you're doing?
> > >
> > > I'm not sure if it is necessary, as on hardware there is no difference
> > > between
> > > vmovdqu16/vmovups. If vmovups already has the capability to represent
> > > EGPR why do we need to distinguish them under VL?
> >
> > On the Intel HW you're currently planning.
> > Will that be the case for AMD as well?
> > Some insns are documented to move float or double vectors while others
> > integer vectors (of different element sizes).
> > Or is vmovups with GPR32 at least encoded smaller than vmovdqu{16,32,64}?
>
> With GPR32 they have same encoding size. If we need to strictly follow
> the meaning of mnemonics,
> I will adjust as you suggested. Thanks.
I think it is useful, even if just for those who try to read the
assembler/disassembler. Of course, if there are cases where only one of
those has to be used (say -mavx -mno-avx2 and 256-bit integer vector moves),
there is no way around that and one just uses what is available.
Jakub
Re: [PATCH 08/13] [APX EGPR] Handle GPR16 only vector move insns
Jakub Jelinek 于2023年9月1日周五 17:20写道：
>
> On Fri, Sep 01, 2023 at 05:07:53PM +0800, Hongyu Wang wrote:
> > Jakub Jelinek via Gcc-patches 于2023年8月31日周四
> > 17:44写道：
> > >
> > > On Thu, Aug 31, 2023 at 04:20:19PM +0800, Hongyu Wang via Gcc-patches
> > > wrote:
> > > > For vector move insns like vmovdqa/vmovdqu, their evex counterparts
> > > > requrire explicit suffix 64/32/16/8. The usage of these instruction
> > > > are prohibited under AVX10_1 or AVX512F, so for AVX2+APX_F we select
> > > > vmovaps/vmovups for vector load/store insns that contains EGPR.
> > >
> > > Why not make it dependent on AVX512VL?
> > > I.e. if egpr_p && TARGET_AVX512VL, still use vmovdqu16 or vmovdqa16
> > > and the like, and only if !evex_reg_p && egpr_p && !TARGET_AVX512VL
> > > fall back to what you're doing?
> >
> > I'm not sure if it is necessary, as on hardware there is no difference
> > between
> > vmovdqu16/vmovups. If vmovups already has the capability to represent
> > EGPR why do we need to distinguish them under VL?
>
> On the Intel HW you're currently planning.
> Will that be the case for AMD as well?
> Some insns are documented to move float or double vectors while others
> integer vectors (of different element sizes).
> Or is vmovups with GPR32 at least encoded smaller than vmovdqu{16,32,64}?
With GPR32 they have same encoding size. If we need to strictly follow
the meaning of mnemonics,
I will adjust as you suggested. Thanks.
>
> Jakub
>
Re: [PATCH 08/13] [APX EGPR] Handle GPR16 only vector move insns
On Fri, Sep 01, 2023 at 05:07:53PM +0800, Hongyu Wang wrote:
> Jakub Jelinek via Gcc-patches 于2023年8月31日周四 17:44写道：
> >
> > On Thu, Aug 31, 2023 at 04:20:19PM +0800, Hongyu Wang via Gcc-patches wrote:
> > > For vector move insns like vmovdqa/vmovdqu, their evex counterparts
> > > requrire explicit suffix 64/32/16/8. The usage of these instruction
> > > are prohibited under AVX10_1 or AVX512F, so for AVX2+APX_F we select
> > > vmovaps/vmovups for vector load/store insns that contains EGPR.
> >
> > Why not make it dependent on AVX512VL?
> > I.e. if egpr_p && TARGET_AVX512VL, still use vmovdqu16 or vmovdqa16
> > and the like, and only if !evex_reg_p && egpr_p && !TARGET_AVX512VL
> > fall back to what you're doing?
>
> I'm not sure if it is necessary, as on hardware there is no difference between
> vmovdqu16/vmovups. If vmovups already has the capability to represent
> EGPR why do we need to distinguish them under VL?
On the Intel HW you're currently planning.
Will that be the case for AMD as well?
Some insns are documented to move float or double vectors while others
integer vectors (of different element sizes).
Or is vmovups with GPR32 at least encoded smaller than vmovdqu{16,32,64}?
Jakub
Re: [PATCH 08/13] [APX EGPR] Handle GPR16 only vector move insns
Jakub Jelinek via Gcc-patches 于2023年8月31日周四 17:44写道： > > On Thu, Aug 31, 2023 at 04:20:19PM +0800, Hongyu Wang via Gcc-patches wrote: > > For vector move insns like vmovdqa/vmovdqu, their evex counterparts > > requrire explicit suffix 64/32/16/8. The usage of these instruction > > are prohibited under AVX10_1 or AVX512F, so for AVX2+APX_F we select > > vmovaps/vmovups for vector load/store insns that contains EGPR. > > Why not make it dependent on AVX512VL? > I.e. if egpr_p && TARGET_AVX512VL, still use vmovdqu16 or vmovdqa16 > and the like, and only if !evex_reg_p && egpr_p && !TARGET_AVX512VL > fall back to what you're doing? I'm not sure if it is necessary, as on hardware there is no difference between vmovdqu16/vmovups. If vmovups already has the capability to represent EGPR why do we need to distinguish them under VL? > > > > gcc/ChangeLog: > > > > * config/i386/i386.cc (ix86_get_ssemov): Check if egpr is used, > > adjust mnemonic for vmovduq/vmovdqa. > > * config/i386/sse.md > > (*_vinsert_0): > > Check if egpr is used, adjust mnemonic for vmovdqu/vmovdqa. > > (avx_vec_concat): Likewise, and separate alternative 0 to > > avx_noavx512f. > > Jakub >
Re: [PATCH 08/13] [APX EGPR] Handle GPR16 only vector move insns
On Thu, Aug 31, 2023 at 04:20:19PM +0800, Hongyu Wang via Gcc-patches wrote: > For vector move insns like vmovdqa/vmovdqu, their evex counterparts > requrire explicit suffix 64/32/16/8. The usage of these instruction > are prohibited under AVX10_1 or AVX512F, so for AVX2+APX_F we select > vmovaps/vmovups for vector load/store insns that contains EGPR. Why not make it dependent on AVX512VL? I.e. if egpr_p && TARGET_AVX512VL, still use vmovdqu16 or vmovdqa16 and the like, and only if !evex_reg_p && egpr_p && !TARGET_AVX512VL fall back to what you're doing? > > gcc/ChangeLog: > > * config/i386/i386.cc (ix86_get_ssemov): Check if egpr is used, > adjust mnemonic for vmovduq/vmovdqa. > * config/i386/sse.md > (*_vinsert_0): > Check if egpr is used, adjust mnemonic for vmovdqu/vmovdqa. > (avx_vec_concat): Likewise, and separate alternative 0 to > avx_noavx512f. Jakub
