tree 49e1c9e218d6e0065570e51b4954f4d88f920c69
parent 67e71d02c89333be1d9daad53109da051bb84ef8
author Vyacheslav Egorov <vegorov@google.com> 1611659009 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1611659009 +0000

[vm] Fix problems with TTS specialization

* Correctly handle _Smi type when producing TTS for it.
 Previously it would not correctly establish that an instance
 of _Smi is assignable to _Smi causing it to always fall through
 into runtime system;
* Correctly handle Null type as a type argument when checking C<Null>
 is C<X>, if Null is assignable to X we need to explicitly check if
 type argument is Null because cid ranges don't really handle this
 check.
* Strengthen the assert checking that TTS specialization succeeded:
 check that specialization is (bitwise) different from the previous
 version of the stub. If they are equal that means specialization
 failed.

TEST=vm/cc/TTS_SubtypeRangeCheck,vm/cc/TTS_Smi

Change-Id: I151a89b52ae07d7e5acce14f59bcb3226bfa1f36
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/180842
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>