On 32-bit arm, when generating subtype test cache stub,
[delayed_type_args_reg] could be the same as [TypeTestABI::kInstanceReg]
(due to lack of registers).
As a result, when loading delayed type arguments from an instantiated
generic closure, [TypeTestABI::kInstanceReg] is eagerly overwritten,
which results in garbage delayed type arguments.
With the linear probe cache this would cause repeated cache misses.
With the hash-based cache this would cause a crash.
Bug: b/507666702
Change-Id: I1093f9277d874154a121ef644ecd7aa76320f789
TEST=runtime/tests/vm/dart/regress_b_507666702_test.dart
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/500842
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Alexander Markov
69b84908a5