tree 221c8006eca18e3f9e1e0cfc653907c3c40c8fdc
parent 20fde9a6a863dd761b8875723fba6f8354751bd1
author Alexander Markov <alexmarkov@google.com> 1555612309 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1555612309 +0000

[vm/compiler] Do not generate unnecessary field length guards

GuardFieldLengthInstr::EmitNativeCode aborts background compilation
if we're not tracking list length for a field
(guarded_list_length() == Field::kNoFixedLength).
I'm seeing a lot of aborted background compilations on a Flutter app with
the reason "GuardFieldLengthInstr: field state changed while compiling".

This CL avoids generating these useless (and harmful) GuardFieldLengthInstr
if not tracking list length for a field.

Change-Id: I2a083c5df35e89893c9e787bebe4e3e7d8177c83
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/99737
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Aart Bik <ajcbik@google.com>