tree c8551cca7ea14f12092e018e1ce5f01df19c8c71
parent eec96f9076c552112ccb0b8ff3f8aa36523e9377
author Vyacheslav Egorov <vegorov@google.com> 1536946752 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1536946752 +0000

[vm/compiler] Support materializing unboxed variables when entering catch.

Previously we tried to rely on the assumption that all variables would be
boxed - so the machinery for setting correct catch-entry state only
supported tagged values and constants. However this both leads to worse code
and is not entirely correct assumption.

This also:

- renames various confusingly named classes: we move away from talking
about "catch entry state" to "catch entry moves" - because we only
record a subset of moves that needs to be performed and that does
not describe the whole state;
- refactors a bunch of associated code to be more readable and maintainable;
- adds documentation about catch implementation in optimized code
to runtime/docs/compiler;

Fixes https://github.com/flutter/flutter/issues/21685.

Change-Id: I03ae361a1bb7710acbd9f661ae014e663a163c59
Reviewed-on: https://dart-review.googlesource.com/74860
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>