RFR: 8373697: AArch64: Remove deoptimization stub code for nmethods with small stack frames

[Dean Long]

On Tue, 16 Dec 2025 23:15:12 GMT, Ruben <duke at openjdk.org> wrote:

> Removal of deoptimization stub codes improves density of compiled code.
> It is possible at least for methods with relatively small stack frames.

I can see what you did, and it is very clever, but it would be nice to have it described, at least at a high level, in the comments somewhere and here in the PR.  Also, should we consider alternative solutions, like putting the original pc at a fixed slot in the compiled frames?

src/hotspot/share/opto/output.cpp line 1794:

> 1792:     }
> 1793:     // Emit the deopt handler code if needed.
> 1794:     if (AlwaysEmitDeoptStubCode

I count 5 times this same expression is repeated.  Maybe it would make sense to move it to an inlined helper function.

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PR Comment: https://git.openjdk.org/jdk/pull/28857#issuecomment-3663343041
PR Review Comment: https://git.openjdk.org/jdk/pull/28857#discussion_r2625364847