* Disable RX workarounds on simulators: they cause host OS to crash;
* Remove Mac OS test for RX workarounds: it can cause host OS to crash;
* Remove old outdated code paths for OS versions that don't
need workarounds.
* Add code which detects whether workaround worked or not by intercepting EXC_BAD_ACCESS.
* Avoid using vm_remap in FFI callbacks when JITing, it does not work.
Instead restore old logic which manually copies page content, but adjust
FFI callbacks implementation to respect possible dual mapping.
This reworks changes done in commit
d194fcecaf after additional testing on a
wider range of hardware.
TEST=manually on physical devices and simulators
Change-Id: I339379386183c532fec25e88fa436ff0b970c2cf
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/435120
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
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>
i.e. #ifndef VM_WHATEVER -> #ifndef RUNTIME_VM_WHATEVER
This lets us remove a hack from the PRESUBMIT.py script that existed
for reasons that are no longer valid, and sets us up to add some
presubmit checks for the GN build.
R=asiva@google.com, rmacnak@google.com
Review URL: https://codereview.chromium.org/2450713004 .