1619932a65
Migrate to op2. Making a few decisions to get this across the line: - Empty slices, no matter where the come from, are null pointers. The v8 bugs (https://bugs.chromium.org/p/v8/issues/detail?id=13489) and (https://bugs.chromium.org/p/v8/issues/detail?id=13488) make passing around zero-length slice pointers too dangerous as they might be uninitialized or null data. - Offsets and lengths are `#[number] isize` and `#[number] usize` respectively -- 53 bits should be enough for anyone - Pointers are bigints. This is a u64 in the fastcall world, and can accept Integer/Int32/Number/BigInt v8 types in the slow world. |
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|---|---|---|
| .. | ||
| 00_ffi.js | ||
| call.rs | ||
| callback.rs | ||
| Cargo.toml | ||
| dlfcn.rs | ||
| ir.rs | ||
| lib.rs | ||
| README.md | ||
| repr.rs | ||
| static.rs | ||
| symbol.rs | ||
| turbocall.rs | ||
deno_ffi
This crate implements dynamic library ffi.
Performance
Deno FFI calls have extremely low overhead (~1ns on M1 16GB RAM) and perform on par with native code. Deno leverages V8 fast api calls and JIT compiled bindings to achieve these high speeds.
Deno.dlopen generates an optimized and a fallback path. Optimized paths are
triggered when V8 decides to optimize the function, hence call through the Fast
API. Fallback paths handle types like function callbacks and implement proper
error handling for unexpected types, that is not supported in Fast calls.
Optimized calls enter a JIT compiled function "trampoline" that translates Fast
API values directly for symbol calls. JIT compilation itself is super fast,
thanks to tinycc. Currently, the optimized path is only supported on Linux and
MacOS.
To run benchmarks:
target/release/deno bench --allow-ffi --allow-read --unstable ./test_ffi/tests/bench.js