tree a612b7821ec48ad99836304a01125d59b3433bef
parent a226405a70c31a418be2243487d8d3882fa5e03e
author Vyacheslav Egorov <vegorov@google.com> 1749786414 -0700
committer Commit Queue <dart-scoped@luci-project-accounts.iam.gserviceaccount.com> 1749786414 -0700

[vm] Use dual mapping of code pages on certain OS versions

Heap references always point into R/RW mapping (this simplifies the
marker) and entry points are retargeted into RX.

To simplify implementation we assume that there are no image pages
created - which means we can always go from Instructions to the start of
the page and check where it is dual mapped to.

TEST=vm/dart/macos_dual_mapping_smoke_test and manually on physical
device

Change-Id: Idbe02b7b695b3c048072cf92f7d062f5ab6e1beb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/433940
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>