This CL enables dart:ffi on Fuchsia.
It has the necessary VM changes for x64 and arm64.
- Allocate VM callback trampoline memory pages with RX.
- Do not use x18 on arm64.
- Save x18 on arm64 in Thread to be able to restore it on exceptions.
We do not have a bot testing this
https://github.com/dart-lang/sdk/issues/38752.
The bot only tests the build, it does not run the emulator.
Manual build and test steps x64 Fuchsia emulator:
```
tools/build.py --os=fuchsia -m debug fuchsia_ffi_test_package
xvfb-run third_party/fuchsia/sdk/linux/bin/femu.sh --image qemu-x64 -N --headless
third_party/fuchsia/sdk/linux/bin/fserve.sh --bucket fuchsia-sdk --image qemu-x64 --device-name step-atom-yard-juicy
third_party/fuchsia/sdk/linux/bin/fpublish.sh out/DebugFuchsiaX64/gen/dart_ffi_test_debug/dart_ffi_test_debug.far
third_party/fuchsia/sdk/linux/bin/fssh.sh --device-name step-atom-yard-juicy run fuchsia-pkg://fuchsia.com/dart_ffi_test_debug#meta/dart.cmx --ignore-unrecognized-flags --packages=/pkg/data/.packages --disable-dart-dev /pkg/data/tests/ffi/all_positive.dart
```
Manual build and test steps arm64 Fuchsia emulator:
```
tools/build.py --no-start-goma --os=fuchsia -m debug -a arm64 fuchsia_ffi_test_package
xvfb-run third_party/fuchsia/sdk/linux/bin/femu.sh --image qemu-arm64 -N --headless --experiment-arm64
third_party/fuchsia/sdk/linux/bin/fserve.sh --bucket fuchsia-sdk --image qemu-arm64 --device-name step-atom-yard-juicy
third_party/fuchsia/sdk/linux/bin/fpublish.sh out/DebugFuchsiaARM64/gen/dart_ffi_test_debug/dart_ffi_test_debug.far
third_party/fuchsia/sdk/linux/bin/fssh.sh --device-name step-atom-yard-juicy run fuchsia-pkg://fuchsia.com/dart_ffi_test_debug#meta/dart.cmx --ignore-unrecognized-flags --packages=/pkg/data/.packages --disable-dart-dev /pkg/data/tests/ffi/all_positive.dart
```
Note that running on the arm64 emulator takes over an hour.
This has been tested on an Estelle device.
TEST=Manual test steps above.
The AOT mode has seen an initial test in g3 by rolling gen_snapshot and
the flutter runner.
Arm64 x18 treatment along the lines of
https://dart-review.googlesource.com/c/sdk/+/119481:
- FfiCallInstr, does not modify x18 at all. We do not have to do
anything special when having a C++ frame on top of a Dart frame.
- NativeEntryInstr and NativeReturnInstr, saves and restores x18 with
PushNativeCalleeSavedRegisters && PopNativeCalleeSavedRegisters. Also
save to the thread field in both places. That way the JumpToFrame stub
can load from the thread field.
Closes: https://github.com/dart-lang/sdk/issues/44434
Change-Id: Ide29369c878fed5909a0d6f7d4c3f7508e179f25
Cq-Include-Trybots: luci.dart.try:vm-fuchsia-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/173273
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Daco Harkes
15dfcca89f