![]() Updates to use rust 1.85. Doesn't move to the 2024 edition, as that's a fair bit more involved. A nice side benefit is that the new rustc version seems to lead to a slight reduction in binary size (at least on mac): ``` FILE SIZE -------------- +4.3% +102Ki __DATA_CONST,__const [NEW] +69.3Ki __TEXT,__literals [NEW] +68.5Ki Rebase Info +5.0% +39.9Ki __TEXT,__unwind_info +57% +8.85Ki [__TEXT] [NEW] +8.59Ki Lazy Binding Info [NEW] +5.16Ki __TEXT,__stub_helper [NEW] +3.58Ki Export Info [NEW] +3.42Ki __DATA,__la_symbol_ptr -0.1% -726 [12 Others] -21.4% -3.10Ki [__DATA_CONST] -95.8% -3.39Ki __DATA_CONST,__got -20.9% -3.43Ki [__DATA] -0.5% -4.52Ki Code Signature -100.0% -11.6Ki [__LINKEDIT] -1.0% -43.5Ki Symbol Table -1.6% -44.0Ki __TEXT,__gcc_except_tab -0.2% -48.1Ki __TEXT,__const -3.3% -78.6Ki __TEXT,__eh_frame -0.7% -320Ki __TEXT,__text -1.5% -334Ki String Table -0.5% -586Ki TOTAL ``` |
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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-ffi ./tests/ffi/tests/bench.js