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During FFI leaf calls, the Dart GC will not run. This means that we can pass pointers into `TypedData` to FFI calls that take `Pointer` arguments. After this CL, we have three types of arguments that can flow into `Pointer` argument in an FFI call: * `Pointer`. * `TypedData`: Any typed data including views. * `_Compound`: A TypedData/Pointer and an offset in bytes. The is only possible for `@Native external` functions, `asFunction` does not support passing in `TypedData`. (See related GitHub issues for discussion. TLDR: FFIgen should generate bindings without config.) `.address` expressions on `TypedData` and `Array` elements do _not_ introduce bounds checks, even though `TypedData` and `Array` have bounds information. E.g. `ffiNative(Uint8List(10)[20].address)` does not throw. Implementation details: The CFE analyzes call-sites to `@Native external` functions. If the arguments are `.address` expressions, it transforms the call site to pass the compound or `TypedData`. If an additional offset needs to be applied, the CFE constructs a new `_Compound` with the correct offset in bytes. The CFE then also creates a new `@Native external` function which have `TypedData`s and `_Compound`s parameters. To avoid name clashes, these functions are postfixed with `#` and `P`, `T`, or `C` for each Pointer parameter. TEST=pkg/vm/testcases/transformations/ffi/address_of_* In the VM, `TypedData` arguments are passed as tagged values, and the address is loaded inside the `FfiCallInstr`. `_Compound` arguments turn into two IL definitions, one for the `TypedDataBase` (tagged), and one for the offset in bytes (unboxed). The address is then loaded inside the `FfiCallInstr` and the offset in bytes is applied. Adding the offset in bytes required an extra temp register for ia32. Also, it uncovered that the temp register in arm32 was conflicting with the argument registers. However, TMP should suffice instead. TEST=tests/ffi/address_of_array_generated_test.dart TEST=tests/ffi/address_of_struct_generated_test.dart TEST=tests/ffi/address_of_typeddata_generated_test.dart Closes: https://github.com/dart-lang/sdk/issues/44589 Closes: https://github.com/dart-lang/sdk/issues/54771 CoreLibraryReviewExempt: VM only, unsupported in dart2wasm Change-Id: I01fb428cfd6f9096a34689c2819c124a8003cb6b Cq-Include-Trybots: dart/try:vm-aot-android-release-arm64c-try,vm-aot-android-release-arm_x64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-release-arm64-try,vm-aot-mac-release-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-aot-win-debug-x64c-try,vm-aot-win-release-x64-try,vm-appjit-linux-debug-x64-try,vm-asan-linux-release-x64-try,vm-checked-mac-release-arm64-try,vm-eager-optimization-linux-release-ia32-try,vm-eager-optimization-linux-release-x64-try,vm-ffi-android-debug-arm64c-try,vm-ffi-qemu-linux-release-arm-try,vm-ffi-qemu-linux-release-riscv64-try,vm-linux-debug-ia32-try,vm-linux-debug-x64-try,vm-linux-debug-x64c-try,vm-mac-debug-arm64-try,vm-mac-debug-x64-try,vm-msan-linux-release-x64-try,vm-reload-linux-debug-x64-try,vm-reload-rollback-linux-debug-x64-try,vm-ubsan-linux-release-x64-try,vm-win-debug-arm64-try,vm-win-debug-x64-try,vm-win-debug-x64c-try,vm-win-release-ia32-try Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/360882 Reviewed-by: Jens Johansen <jensj@google.com> Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Reviewed-by: Martin Kustermann <kustermann@google.com> Commit-Queue: Daco Harkes <dacoharkes@google.com> Reviewed-by: Tess Strickland <sstrickl@google.com> Reviewed-by: Lasse Nielsen <lrn@google.com> |
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| .. | ||
| abi.dart | ||
| abi_specific.dart | ||
| allocation.dart | ||
| annotations.dart | ||
| c_type.dart | ||
| dynamic_library.dart | ||
| ffi.dart | ||
| ffi_sources.gni | ||
| native_finalizer.dart | ||
| native_type.dart | ||
| struct.dart | ||
| union.dart | ||