RFR: 8344068: Windows x86-64: Out of CodeBuffer space when generating final stubs

[Vladimir Kozlov]

On Tue, 3 Dec 2024 17:26:36 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

>> src/hotspot/cpu/x86/stubRoutines_x86.hpp line 41:
>> 
>>> 39:   // Windows have more code to save/restore registers
>>> 40:   _compiler_stubs_code_size     = 20000 LP64_ONLY(+47000) WINDOWS_ONLY(+2000),
>>> 41:   _final_stubs_code_size        = 10000 LP64_ONLY(+20000) WINDOWS_ONLY(+22000) ZGC_ONLY(+20000)
>> 
>> Do you know which particular stubs cause out of space?
>> Most stubs are generated for `compiler` intrinsics. I would assume that they are causing the issue and not `final` 6 stubs.
>
> Scratch that. I see call stack in the bug report. It is indeed final stubs for upcall stub when ZGC is enabled.
> Should we increase ZGC_ONLY(+20000) value instead?

ZGC save/restores XMM registers regardless OS: [x86/gc/z/zBarrierSetAssembler_x86.cpp#L70](https://github.com/openjdk/jdk/blob/master/src/hotspot/cpu/x86/gc/z/zBarrierSetAssembler_x86.cpp#L70)

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PR Review Comment: https://git.openjdk.org/jdk/pull/22516#discussion_r1868234509