In async/async* methods synthetic :try_finally_return_value variable
(which is used to hold return value across finally) could be
captured, so flow graph builder needs to have correct context_depth_
in order to access it using LoadLocal(finally_return_variable)
when building flow graph for return statement.
Previously, flow graph builder left context in an unspecified state
and depth after TranslateFinallyFinalizers(NULL, -1), which caused
incorrect code being generated for LoadLocal(finally_return_variable).
This change fixes this problem by
* passing correct target_context_depth to TranslateFinallyFinalizers
so context is adjusted to a known depth regardless of context
depth which is used by finally;
* setting context_depth_ for LoadLocal(finally_return_variable)
and then restoring it (to be able to continue building flow graph
for the enclosing AST nodes).
TEST=tests/language/async_star/regression_47610_test.dart
Fixes https://github.com/dart-lang/sdk/issues/47610
Change-Id: Id15ea719ddda892eaff0b06f6450b1a8de36e8da
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/219283
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Alexander Markov
9b7caf3b93