RFR: JDK-8302320: AsyncGetCallTrace obtains too few frames in sanity test

Tue Feb 14 09:24:43 UTC 2023

On Tue, 14 Feb 2023 07:38:21 GMT, Johannes Bechberger <duke at openjdk.org> wrote:

>> The test fails without this relaxation and the relaxation has been used on PPC to solve a similar issue a few years back.
>
> The original assumption does not always hold anymore and should therefore relaxed.

I think `unextended_sp < sp` is possible on x86 when interpreter entries generated by `MethodHandles::generate_method_handle_interpreter_entry()` are executed. They modify `sp` ([here for example](https://github.com/openjdk/jdk/blob/7f71a1040d9c03f72d082e329ccaf2c4a3c060a6/src/hotspot/cpu/x86/methodHandles_x86.cpp#L310-L314)) but not `sender_sp` (`InterpreterMacroAssembler ::_bcp_register`).

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PR: https://git.openjdk.org/jdk/pull/12535