tarantool / luajit / 23743685268

93%

tarantool/master: 93%

Build Type

push

github

Committed by Buristan

Commit Message

Avoid recording interference due to invocation of VM hooks.

Thanks to Sergey Kaplun.

(cherry picked from commit ab834de8b)

If the VM event contains a trace, it may cause several inconsistencies
during the recording of another trace:

- If there is an exit from the trace in the VM event for the 'trace
  start' VM event, the JIT engine converts the newly recorded trace to
  the "side trace". So, when this side exit is taken, the JIT returns
  from the VM event in the middle of another frame.

- Stitching semantics are broken for the VM events due to an
  inconsistent frame link chain.

This patch fixes these issues by forbidding stitching in the VM event
and saving the context of the JIT engine at the VM event for trace
start.

Sergey Kaplun:
* added the description and the test for the problem

Part of tarantool/tarantool#12134

Coverage Stats

5721 of 6056 branches covered (94.47%)

Branch coverage included in aggregate %.

11 of 11 new or added lines in 2 files covered. (100.0%)

2 existing lines in 1 file now uncovered.

21836 of 23545 relevant lines covered (92.74%)

3973024.85 hits per line