RFR: 8160821: VarHandle accesses are penalized when argument conversion is required [v13]

[John R Rose]

On Fri, 23 Jan 2026 20:08:58 GMT, Chen Liang <liach at openjdk.org> wrote:

>> Since access descriptor is created for each VH operation site, we can optimistically cache the adapted method handle in a site if the site operates on a constant VH.  Used a C2 IR test to verify such a setup through an inexact VarHandle invocation can be constant folded through (previously, it was blocked by `asType`)
>
> Chen Liang has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Wording update, thanks Jorn

make/jdk/src/classes/build/tools/methodhandle/VarHandleGuardMethodGenerator.java line 130:

> 128: 
> 129:     // The void bypass is necessary if a (name + return-dropping type) combination has multiple call sites, each
> 130:     // having its own constant VarHandle. In that case, the AccessMode::adaptedMethodHandle adaption mechanism

wrong word:  s/adaption/adaptation/

https://grammarist.com/usage/adaption-adaptation/

(Wiktionary implies they are the same, but they apply to different areas of discourse.  The grammarist article indicates that "adaptation" is the more correct word here.  Also, the word "adaption" seems to be mostly obsolete.)

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PR Review Comment: https://git.openjdk.org/jdk/pull/28585#discussion_r2723023261