RFR: 8300002: Performance regression caused by non-inlined hot methods due to post call noop instructions

Thu Jan 12 18:14:24 UTC 2023

On Thu, 12 Jan 2023 02:52:17 GMT, Sergey Kuksenko <skuksenko at openjdk.org> wrote:

> 8300002: Performance regression caused by non-inlined hot methods due to post call noop instructions

As an alternative way to count nops, have you considered iterating over relocations and counting `post_call_nop_Reolcation`s then multiplying the count by `NativePostCallNop::instruction_size`? (So far, there's no `NativePostCallNop::instruction_size` declared on aarch64 and ppc, but that's the common pattern in nativeInst_*.hpp.)

BTW I'm curious why there's no relocation registered on PPC while both x86 and aarch64 have it.

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PR: https://git.openjdk.org/jdk/pull/11958