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8fe9b8a4cc
Implements `Result` in fast-calls. Note that the approach here is slightly different. Rather than store the last result in the `OpState`, we put it into the `OpCtx` which saves us a lookup and lock in the error case. We do not have to lock this field as it's guaranteed only one runtime and thread can ever access it. The fastcall path for many ops can avoid doing a great deal of work, even for `Result` return values. In the previous iteration of `ops`, all `Result`-returning functions would fetch and lock the `OpState`, regardless of whether it was used or not. |
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.. | ||
op2 | ||
optimizer_tests | ||
tests/compile_fail | ||
attrs.rs | ||
Cargo.toml | ||
deno.rs | ||
fast_call.rs | ||
lib.rs | ||
optimizer.rs | ||
README.md |
deno_ops
proc_macro
for generating highly optimized V8 functions from Deno ops.
// Declare an op.
#[op(fast)]
pub fn op_add(_: &mut OpState, a: i32, b: i32) -> i32 {
a + b
}
// Register with an extension.
Extension::builder()
.ops(vec![op_add::decl()])
.build();
Performance
The macro can optimize away code, short circuit fast paths and generate a Fast API impl.
Cases where code is optimized away:
-> ()
skips serde_v8 andrv.set
calls.-> Result<(), E>
skips serde_v8 andrv.set
calls forOk()
branch.-> ResourceId
or-> [int]
types will use specialized method likev8::ReturnValue::set_uint32
. A fast path for SMI.-> Result<ResourceId, E>
or-> Result<[int], E>
types will be optimized like above for theOk()
branch.
Fast calls
The macro will infer and try to auto generate V8 fast API call trait impl for
sync
ops with:
- arguments: integers, bool,
&mut OpState
,&[u8]
,&mut [u8]
,&[u32]
,&mut [u32]
- return_type: integers, bool
The #[op(fast)]
attribute should be used to enforce fast call generation at
compile time.
Trait gen for async
ops & a ZeroCopyBuf equivalent type is planned and will be
added soon.
Wasm calls
The #[op(wasm)]
attribute should be used for calls expected to be called from
Wasm. This enables the fast call generation and allows seamless WasmMemory
integration for generic and fast calls.
#[op(wasm)]
pub fn op_args_get(
offset: i32,
buffer_offset: i32,
memory: Option<&[u8]>, // Must be last parameter. Some(..) when entered from Wasm.
) {
// ...
}