This is a revert of b6bbfff8c0c6c44cdab0d7d78 which temporarily disabled
this.
Turns out that a non-TSAN gen_snapshot would - when emitting code via
`Assembler::TsanLoadAcquire` - use an incorrect `Thread`-offset:
It calculated the offset via `Thread::OffsetFromThread`. That function
took a `dart::RuntimeEntry*` and tried to find its offset.
We happen to have the following leaf runtime entries:
#define LEAF_RUNTIME_ENTRY_LIST(V)
...
V(void, MsanUnpoison, void*, size_t)
V(void, MsanUnpoisonParam, size_t)
V(void, TsanLoadAcquire, void*)
V(void, TsanStoreRelease, void*)
...
It loops over all runtime entries and finds the first one that has the
identical `dart::RuntimeEntry::function_` pointer.
Though all 4 of them are `nullptr` at `gen_snapshot` time, so when
searching for offset for
`Thread::OffsetFromThread(kTsanLoadAcquireRuntimeEntry)`
it looked for the first runtime entry with `nullptr` function pointer -
which turned out to be `MsanUnpoison` (instead of `TsanLoadAcquire`).
=> The obvious fix is to use the `dart::RuntimeEntry*` pointer for
comparison instead of it's `function_` member.
TEST=ci
Issue b/287638965
Change-Id: I85c06674927978ef8561e9e7bdfab4823c0a8e1c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/312902
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Martin Kustermann
389aab624d