RFR: 8357258: x86: Improve receiver type profiling reliability [v3]

[Vladimir Kozlov]

On Fri, 21 Nov 2025 19:19:20 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

>> Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains four commits:
>> 
>>  - Merge branch 'master' into JDK-8357258-x86-c1-optimize-virt-calls
>>  - Merge branch 'master' into JDK-8357258-x86-c1-optimize-virt-calls
>>  - Drop atomic counters
>>  - Initial version
>
> src/hotspot/cpu/x86/c1_LIRAssembler_x86.cpp line 1258:
> 
>> 1256:                                         Register recv) {
>> 1257:   int mdp_offset = md->byte_offset_of_slot(data, in_ByteSize(0));
>> 1258:   __ type_profile(recv, mdo, mdp_offset);
> 
> I looked on callers and `mdo` is not used after this code. I think we can convert it into `mdp` by adding `mdp_offset` so you don't need 3rd parameter for `type_profile()`.

Hmm, but it will be additional instruction. I withdraw this suggestion.

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PR Review Comment: https://git.openjdk.org/jdk/pull/25305#discussion_r2550940821