This CL enables tree shaking of `Struct` sub classes by simulating the
native behavior in Dart code.
We call the struct constructors in let expressions where FFI trampolines
are created which allocate these struct objects in native code. This way
TFA is instructed about the native behavior. The VM recognizes these
constructor calls as dead code and removes them.
For more info see go/dart-ffi-struct-treeshaking.
Closes: https://github.com/dart-lang/sdk/issues/38721
This CL fixes the types on the generated #fromTypedDataBase constructors.
Also, this CL also cleans up the struct naming:
* _addressOf -> _typedDataBase
* _fromPointer -> _fromTypedDataBase
* #pointer -> #typedDataBase
These cleanups are not split into a separate CL to prevent updating
the .expect files multiple times.
Finally, this CL enables running a single transformer test through:
`dart pkg/vm/test/transformations/type_flow/transformer_test.dart name`
TEST=pkg/vm/testcases/transformations/type_flow/transformer/ffi_struct_constructors.dart
TEST=tests/ffi(_2)/function_callbacks_structs_by_value_generated_test.dart
TEST=tests/ffi(_2)/function_structs_by_value_generated_test.dart
Change-Id: I418d0d73bc86b234dfe5b7b04ae726c33d2b8aeb
Cq-Include-Trybots: luci.dart.try:vm-precomp-ffi-qemu-linux-release-arm-try,vm-ffi-android-debug-arm64-try,vm-kernel-precomp-asan-linux-release-x64-try,vm-kernel-precomp-dwarf-linux-product-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-obfuscate-linux-release-x64-try,analyzer-analysis-server-linux-try,analyzer-linux-release-try,dart-sdk-linux-try,vm-kernel-reload-rollback-linux-debug-x64-try,vm-kernel-reload-linux-debug-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/193661
Commit-Queue: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Daco Harkes
d27f166b75