tarantool / luajit / 7119175130

70%

tarantool/master: 93%

Build Type

push

github

Committed by igormunkin

Commit Message

Fix HREFK forwarding vs. table.clear().

Reported by XmiliaH.

(cherry-picked from commit d5a237eae)

When performing HREFK (and also ALOAD, HLOAD) forwarding optimization,
the `table.clear()` function call may be performed on the table operand
from HREFK between table creation and IR, from which value is forwarded.
This call isn't taken in the account, so it may lead to too optimistic
value-forwarding from NEWREF (and also ASTORE, HSTORE), or the omitted
type guard for HREFK operation. Therefore, this leads to incorrect trace
behaviour (for example, taking a non-nil value from the cleared table).

This patch adds necessary checks for `table.clear()` calls.

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

Part of tarantool/tarantool#9145

Reviewed-by: Maxim Kokryashkin <m.kokryashkin@tarantool.org>
Reviewed-by: Sergey Bronnikov <sergeyb@tarantool.org>
Signed-off-by: Igor Munkin <imun@tarantool.org>
(cherry picked from commit aed147cd9)

Run Details

5361 of 5969 branches covered (0.0%)

Branch coverage included in aggregate %.

12 of 12 new or added lines in 1 file covered. (100.0%)

6 existing lines in 2 files now uncovered.

20533 of 23266 relevant lines covered (88.25%)

705930.85 hits per line