On Fri, 25 Jun 2021 17:38:32 GMT, Jorn Vernee <[email protected]> wrote:
> This patch rewrites the prologue and epilogue of panama upcalls, in order to
> fix the test failure from the title.
>
> Previously, we did a call to potentially attach the current thread to the VM,
> and then afterwards did the same suspend and stack reguard checks that we do
> on the back-edge of a native downcall. Then, on the back edge of the upcall
> we did another conditional call to detach the thread.
>
> The suspend and reguard checks on the front-edge are incorrect, so I've
> changed the 2 calls to mimic what is done by JavaCallWrapper instead (with
> attach and detach included), and removed the old suspend and stack reguard
> checks.
>
> FWIW, this removes the JavaFrameAnchor save/restore MacroAssembler code. This
> is now written in C++. Also, MacroAssembler code was added to save/restore
> the result of the upcall around the call on the back-edge, which was
> previously missing. Since the new code allocates a handle block as well, I've
> added handling for those oops to frame & OptimizedUpcallBlob.
>
> Testing: local running of `jdk_foreign` on Windows and Linux (WSL). Tier 1-3
Looks good.
src/hotspot/cpu/x86/frame_x86.cpp line 356:
> 354: }
> 355:
> 356: OptimizedEntryBlob::FrameData*
> OptimizedEntryBlob::frame_data_for_frame(const frame& frame) const {
It makes sense to assert that `frame` refers to optimized entry frame
(`assert(frame->is_optimized_entry_frame(), "wrong frame");`.
src/hotspot/share/runtime/thread.hpp line 1128:
> 1126:
> 1127: private:
> 1128: DEBUG_ONLY(void verify_frame_info();)
If you declare `verify_frame_info` as returning a `bool` (and just put a
`return true;` at the end of `JavaThread::verify_frame_info()`), you can call
it as:
assert(verify_frame_info(), "unexpected frame info");
-------------
Marked as reviewed by vlivanov (Reviewer).
PR: https://git.openjdk.java.net/jdk17/pull/149