Re: [PATCH 09/10] Support Intel AMX-FP16

[Jan Beulich <jbeulich@suse.com>]

On 19.10.2022 16:05, Cui, Lili wrote:
> 
>>>> I guess my comment here was a little misleading (I'm sorry for that),
>>>> in that in addition I was expecting you to consider the comment
>>>> regarding the need for the *_ANY_* constants that I did give for several of
>> the patches in this series.
>>>> I think the question applies here as well: Are there dependent
>>>> features known to appear? If not, there's no need for the extra constant.
>>>>
>>> Get you, there are no known dependencies now, and I will pay attention on
>> it in future ISAs.
>>
>> Despite this reply, ...
>>
>>> --- a/gas/config/tc-i386.c
>>> +++ b/gas/config/tc-i386.c
>>> @@ -1076,6 +1076,7 @@ static const arch_entry cpu_arch[] =
>>>    SUBARCH (cldemote, CLDEMOTE, CLDEMOTE, false),
>>>    SUBARCH (amx_int8, AMX_INT8, ANY_AMX_INT8, false),
>>>    SUBARCH (amx_bf16, AMX_BF16, ANY_AMX_BF16, false),
>>> +  SUBARCH (amx_fp16, AMX_FP16, ANY_AMX_FP16, false),
>>
>> ... you still use ANY_... here and ...
>>
>>> --- a/opcodes/i386-gen.c
>>> +++ b/opcodes/i386-gen.c
>>> @@ -319,6 +319,8 @@ static initializer cpu_flag_init[] =
>>>      "CPU_AMX_TILE_FLAGS|CpuAMX_INT8" },
>>>    { "CPU_AMX_BF16_FLAGS",
>>>      "CPU_AMX_TILE_FLAGS|CpuAMX_BF16" },
>>> +  { "CPU_AMX_FP16_FLAGS",
>>> +    "CPU_AMX_TILE_FLAGS|CpuAMX_FP16" },
>>>    { "CPU_AMX_TILE_FLAGS",
>>>      "CpuAMX_TILE" },
>>>    { "CPU_MOVDIRI_FLAGS",
>>> @@ -425,8 +427,10 @@ static initializer cpu_flag_init[] =
>>>      "CpuAMX_INT8" },
>>>    { "CPU_ANY_AMX_BF16_FLAGS",
>>>      "CpuAMX_BF16" },
>>> +  { "CPU_ANY_AMX_FP16_FLAGS",
>>> +    "CpuAMX_FP16" },
>>
>> ... you request it to be constructed here.
> 
> HAHA, you mean if there is no instruction that depends on CpuAMX_FP16, we don’t need to add *ANY* for it in arch_entry cpu_arch[]?  Maybe when the dependency happens, we need to change it back.

Right, that's why I did ask whether there are dependent features known to
appear. If you go look you'll find that we don't have ANY_* for a fair
part (if not a majority) of the features).

Jan