On Wed, 18 Feb 2026 16:28:48 GMT, Marc Chevalier <[email protected]> wrote:

>> Patricio Chilano Mateo has updated the pull request with a new target base 
>> due to a merge or a rebase. The pull request now contains three commits:
>> 
>>  - Review comments
>>  - Merge branch 'lworld' into JDK-8377714
>>  - v1
>
> src/hotspot/share/runtime/continuationFreezeThaw.cpp line 2893:
> 
>> 2891:   // As a result, f.is_deoptimized_frame() is always false and we must 
>> test hf to know if the frame is deoptimized.
>> 2892:   frame f = new_stack_frame<ContinuationHelper::CompiledFrame>(hf, 
>> caller, is_bottom_frame, augmented ? fsize - hf.cb()->frame_size() : 0);
>> 2893:   assert((int)(caller.sp() - f.sp()) == (augmented ? fsize : 
>> f.cb()->frame_size()), "");
> 
> The expression `f.cb()->frame_size()` is not crashing only if `f` is compiled 
> otherwise `f.cb() == nullptr`. But `f` seems to be a compiled frame (since 
> `new_stack_frame<ContinuationHelper::CompiledFrame>`), so why 
> `f.cb()->frame_size()` isn't always what we want?

Right, `f` is a compiled frame. So before this change, `caller.sp()` was always 
set to `f.sp() + f.cb()->frame_size()`, even when `f` was an extended frame. 
The reason for this is that we needed to keep a reference to the saved 
`rbp/rfp` in `f`, because we might needed to patch it later (we need to thaw 
the callee first before patching the caller's saved `rbp/rfp`). But now, the 
saved `rbp/rfp` is stored together with the saved return pc. So `caller.sp()` 
is set to point to `f`'s actual caller `sp`. The difference between 
`caller.sp()` and `f.sp()` should then be the real size of `f` (stored in 
`fsize` for extended frames).

-------------

PR Review Comment: 
https://git.openjdk.org/valhalla/pull/2085#discussion_r2830815120

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