[PATCH, rs6000] Update "prefix" attribute for Power10

[Pat Haugen]

Ping2.

On 1/26/21 11:28 AM, Pat Haugen via Gcc-patches wrote:
> Ping.
> 
> On 12/10/20 3:32 PM, Pat Haugen via Gcc-patches wrote:
>> Update prefixed attribute for Power10.
>>
>>
>> This patch was broken out from my larger patch to update various attributes for
>> Power10, in order to make the review process hopefully easier. This patch only
>> updates the prefix attribute for various new instructions. Changes in this
>> version include missed updates to rs6000_insn_cost and
>> rs6000_adjust_insn_length. I stayed with the new 'always' keyword but added
>> additional commentary so hopefully is more clear.
>>
>> Bootstrap/regtest on powerpc64le (Power8/Power10) with no new regressions. Ok for trunk?
>>
>> -Pat
>>
>>
>> 2020-11-10  Pat Haugen  <pthaugen@linux.ibm.com>
>>
>> gcc/
>> 	* config/rs6000/altivec.md (xxspltiw_v4si, xxspltiw_v4sf_inst,
>> 	xxspltidp_v2df_inst, xxsplti32dx_v4si_inst, xxsplti32dx_v4sf_inst,
>> 	xxblend_<mode>, xxpermx_inst, xxeval): Mark prefixed "always".
>> 	* config/rs6000/mma.md (mma_<vvi4i4i8>, mma_<avvi4i4i8>,
>> 	mma_<vvi4i4i2>, mma_<avvi4i4i2>, mma_<vvi4i4>, mma_<avvi4i4>,
>> 	mma_<pvi4i2>, mma_<apvi4i2>, mma_<vvi4i4i4>, mma_<avvi4i4i4>):
>> 	Likewise.
>> 	* config/rs6000/rs6000.c (rs6000_insn_cost): Update test for prefixed
>> 	insn.
>> 	(next_insn_prefixed_p): Rename to prefix_next_insn_p.
>> 	(rs6000_final_prescan_insn): Only add 'p' for PREFIXED_YES.
>> 	(rs6000_asm_output_opcode): Adjust.
>> 	(rs6000_adjust_insn_length): Update test for prefixed insns.
>> 	* config/rs6000/rs6000.md (define_attr "prefixed"): Add 'always'
>> 	and update commentary.
>>
>