RFR: 8343214: Fix encoding errors in APX New Data Destination Instructions Support

[Srinivas Vamsi Parasa]

On Wed, 30 Oct 2024 07:46:26 GMT, Jatin Bhateja <jbhateja at openjdk.org> wrote:

>> The goal of this PR is to fix instruction encoding errors for some of the instructions which support the APX New Data Destination (NDD) and No Flags (NF) features (added in [JDK-8329035](https://bugs.openjdk.org/browse/JDK-8329035))
>
> src/hotspot/cpu/x86/assembler_x86.cpp line 2632:
> 
>> 2630:   InstructionAttr attributes(AVX_128bit, /* vex_w */ false, /* legacy_mode */ false, /* no_mask_reg */ true, /* uses_vl */ false);
>> 2631:   attributes.set_address_attributes(/* tuple_type */ EVEX_NOSCALE, /* input_size_in_bits */ EVEX_32bit);
>> 2632:   evex_prefix_nf(src, 0, dst->encoding(), VEX_SIMD_NONE, VEX_OPCODE_0F_3C, &attributes, no_flags);
> 
> Could you also replace VEX_OPCODE_OF_3C with the standard naming convention of VEX_OPCODE_MAP4?
> I added /*MAP4*/ in the comments after the prefix for the setzuCC instruction, but it's better to make this change consistently in all places.

Hi Jatin,

If I understand correctly, are you suggesting that I add a comment in front like `/* MAP4 */VEX_OPCODE_0F_3C` for all occurrences of VEX_OPCODE_OF_3C in this PR?

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PR Review Comment: https://git.openjdk.org/jdk/pull/21770#discussion_r1823509217