1
0
Fork 0
mirror of https://github.com/denoland/deno.git synced 2024-11-25 15:29:32 -05:00
denoland-deno/ops/lib.rs
Divy Srivastava 38f0b41e7d
perf(web): optimize single pass utf8 decoding (#16593)
- [x] Avoid copying buffers.

https://encoding.spec.whatwg.org/#dom-textdecoder-decode

> Implementations are strongly encouraged to use an implementation
strategy that avoids this copy. When doing so they will have to make
sure that changes to input do not affect future calls to
[decode()](https://encoding.spec.whatwg.org/#dom-textdecoder-decode).

- [x] Special op to avoid string label deserialization and parsing.
(Ideally we should map labels to integers in JS)
- [x] Avoid webidl `Object.assign` when options is undefined.
2022-11-11 20:07:18 +05:30

670 lines
18 KiB
Rust

// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
use attrs::Attributes;
use once_cell::sync::Lazy;
use optimizer::{BailoutReason, Optimizer};
use proc_macro::TokenStream;
use proc_macro2::{Span, TokenStream as TokenStream2};
use quote::{quote, ToTokens};
use regex::Regex;
use syn::{
parse, parse_macro_input, punctuated::Punctuated, token::Comma, FnArg,
GenericParam, Ident, ItemFn, Lifetime, LifetimeDef,
};
mod attrs;
mod deno;
mod fast_call;
mod optimizer;
#[cfg(test)]
mod tests;
const SCOPE_LIFETIME: &str = "'scope";
/// Add the 'scope lifetime to the function signature.
fn add_scope_lifetime(func: &mut ItemFn) {
let span = Span::call_site();
let lifetime = LifetimeDef::new(Lifetime::new(SCOPE_LIFETIME, span));
let generics = &mut func.sig.generics;
if !generics.lifetimes().any(|def| *def == lifetime) {
generics.params.push(GenericParam::Lifetime(lifetime));
}
}
struct Op {
orig: ItemFn,
item: ItemFn,
/// Is this an async op?
/// - `async fn`
/// - returns a Future
is_async: bool,
type_params: Punctuated<GenericParam, Comma>,
// optimizer: Optimizer,
core: TokenStream2,
attrs: Attributes,
}
impl Op {
fn new(mut item: ItemFn, attrs: Attributes) -> Self {
add_scope_lifetime(&mut item);
// Preserve the original function. Change the name to `call`.
//
// impl op_foo {
// fn call() {}
// ...
// }
let mut orig = item.clone();
orig.sig.ident = Ident::new("call", Span::call_site());
let is_async = item.sig.asyncness.is_some() || is_future(&item.sig.output);
let type_params = exclude_lifetime_params(&item.sig.generics.params);
let core = deno::import();
Self {
orig,
item,
type_params,
is_async,
core,
attrs,
}
}
fn gen(mut self) -> TokenStream2 {
let mut optimizer = Optimizer::new();
match optimizer.analyze(&mut self) {
Ok(_) | Err(BailoutReason::MustBeSingleSegment) => {}
Err(BailoutReason::FastUnsupportedParamType) => {
optimizer.fast_compatible = false;
}
};
let Self {
core,
item,
is_async,
orig,
attrs,
type_params,
} = self;
let name = &item.sig.ident;
let generics = &item.sig.generics;
let where_clause = &item.sig.generics.where_clause;
// First generate fast call bindings to opt-in to error handling in slow call
let fast_call::FastImplItems {
impl_and_fn,
decl,
active,
} = fast_call::generate(&core, &mut optimizer, &item);
let has_fallible_fast_call = active && optimizer.returns_result;
let (v8_body, argc) = if is_async {
codegen_v8_async(
&core,
&item,
attrs,
item.sig.asyncness.is_some(),
attrs.deferred,
)
} else {
codegen_v8_sync(&core, &item, attrs, has_fallible_fast_call)
};
let is_v8 = attrs.is_v8;
let is_unstable = attrs.is_unstable;
let docline = format!("Use `{name}::decl()` to get an op-declaration");
// Generate wrapper
quote! {
#[allow(non_camel_case_types)]
#[doc="Auto-generated by `deno_ops`, i.e: `#[op]`"]
#[doc=""]
#[doc=#docline]
#[doc="you can include in a `deno_core::Extension`."]
pub struct #name;
#[doc(hidden)]
impl #name {
pub fn name() -> &'static str {
stringify!(#name)
}
pub fn v8_fn_ptr #generics () -> #core::v8::FunctionCallback #where_clause {
use #core::v8::MapFnTo;
Self::v8_func::<#type_params>.map_fn_to()
}
pub fn decl #generics () -> #core::OpDecl #where_clause {
#core::OpDecl {
name: Self::name(),
v8_fn_ptr: Self::v8_fn_ptr::<#type_params>(),
enabled: true,
fast_fn: #decl,
is_async: #is_async,
is_unstable: #is_unstable,
is_v8: #is_v8,
argc: #argc,
}
}
#[inline]
#[allow(clippy::too_many_arguments)]
#orig
pub fn v8_func #generics (
scope: &mut #core::v8::HandleScope<'scope>,
args: #core::v8::FunctionCallbackArguments,
mut rv: #core::v8::ReturnValue,
) #where_clause {
#v8_body
}
}
#impl_and_fn
}
}
}
#[proc_macro_attribute]
pub fn op(attr: TokenStream, item: TokenStream) -> TokenStream {
let margs = parse_macro_input!(attr as Attributes);
let func = parse::<ItemFn>(item).expect("expected a function");
let op = Op::new(func, margs);
op.gen().into()
}
/// Generate the body of a v8 func for an async op
fn codegen_v8_async(
core: &TokenStream2,
f: &syn::ItemFn,
margs: Attributes,
asyncness: bool,
deferred: bool,
) -> (TokenStream2, usize) {
let Attributes { is_v8, .. } = margs;
let special_args = f
.sig
.inputs
.iter()
.map_while(|a| {
(if is_v8 { scope_arg(a) } else { None }).or_else(|| opstate_arg(a))
})
.collect::<Vec<_>>();
let rust_i0 = special_args.len();
let args_head = special_args.into_iter().collect::<TokenStream2>();
let (arg_decls, args_tail, argc) = codegen_args(core, f, rust_i0, 1);
let type_params = exclude_lifetime_params(&f.sig.generics.params);
let (pre_result, mut result_fut) = match asyncness {
true => (
quote! {},
quote! { Self::call::<#type_params>(#args_head #args_tail).await; },
),
false => (
quote! { let result_fut = Self::call::<#type_params>(#args_head #args_tail); },
quote! { result_fut.await; },
),
};
let result_wrapper = match is_result(&f.sig.output) {
true => {
// Support `Result<impl Future<Output = Result<T, AnyError>> + 'static, AnyError>`
if !asyncness {
result_fut = quote! { result_fut; };
quote! {
let result = match result {
Ok(fut) => fut.await,
Err(e) => return (promise_id, op_id, #core::_ops::to_op_result::<()>(get_class, Err(e))),
};
}
} else {
quote! {}
}
}
false => quote! { let result = Ok(result); },
};
(
quote! {
use #core::futures::FutureExt;
// SAFETY: #core guarantees args.data() is a v8 External pointing to an OpCtx for the isolates lifetime
let ctx = unsafe {
&*(#core::v8::Local::<#core::v8::External>::cast(args.data()).value()
as *const #core::_ops::OpCtx)
};
let op_id = ctx.id;
let promise_id = args.get(0);
let promise_id = #core::v8::Local::<#core::v8::Integer>::try_from(promise_id)
.map(|l| l.value() as #core::PromiseId)
.map_err(#core::anyhow::Error::from);
// Fail if promise id invalid (not an int)
let promise_id: #core::PromiseId = match promise_id {
Ok(promise_id) => promise_id,
Err(err) => {
#core::_ops::throw_type_error(scope, format!("invalid promise id: {}", err));
return;
}
};
#arg_decls
// Track async call & get copy of get_error_class_fn
let get_class = {
let state = ::std::cell::RefCell::borrow(&ctx.state);
state.tracker.track_async(op_id);
state.get_error_class_fn
};
#pre_result
#core::_ops::queue_async_op(ctx, scope, #deferred, async move {
let result = #result_fut
#result_wrapper
(promise_id, op_id, #core::_ops::to_op_result(get_class, result))
});
},
argc,
)
}
fn scope_arg(arg: &FnArg) -> Option<TokenStream2> {
if is_handle_scope(arg) {
Some(quote! { scope, })
} else {
None
}
}
fn opstate_arg(arg: &FnArg) -> Option<TokenStream2> {
match arg {
arg if is_rc_refcell_opstate(arg) => Some(quote! { ctx.state.clone(), }),
arg if is_mut_ref_opstate(arg) => {
Some(quote! { &mut std::cell::RefCell::borrow_mut(&ctx.state), })
}
_ => None,
}
}
/// Generate the body of a v8 func for a sync op
fn codegen_v8_sync(
core: &TokenStream2,
f: &syn::ItemFn,
margs: Attributes,
has_fallible_fast_call: bool,
) -> (TokenStream2, usize) {
let Attributes { is_v8, .. } = margs;
let special_args = f
.sig
.inputs
.iter()
.map_while(|a| {
(if is_v8 { scope_arg(a) } else { None }).or_else(|| opstate_arg(a))
})
.collect::<Vec<_>>();
let rust_i0 = special_args.len();
let args_head = special_args.into_iter().collect::<TokenStream2>();
let (arg_decls, args_tail, argc) = codegen_args(core, f, rust_i0, 0);
let ret = codegen_sync_ret(core, &f.sig.output);
let type_params = exclude_lifetime_params(&f.sig.generics.params);
let fast_error_handler = if has_fallible_fast_call {
quote! {
{
let op_state = &mut std::cell::RefCell::borrow_mut(&ctx.state);
if let Some(err) = op_state.last_fast_op_error.take() {
let exception = #core::error::to_v8_error(scope, op_state.get_error_class_fn, &err);
scope.throw_exception(exception);
return;
}
}
}
} else {
quote! {}
};
(
quote! {
// SAFETY: #core guarantees args.data() is a v8 External pointing to an OpCtx for the isolates lifetime
let ctx = unsafe {
&*(#core::v8::Local::<#core::v8::External>::cast(args.data()).value()
as *const #core::_ops::OpCtx)
};
#fast_error_handler
#arg_decls
let result = Self::call::<#type_params>(#args_head #args_tail);
// use RefCell::borrow instead of state.borrow to avoid clash with std::borrow::Borrow
let op_state = ::std::cell::RefCell::borrow(&*ctx.state);
op_state.tracker.track_sync(ctx.id);
#ret
},
argc,
)
}
/// (full declarations, idents, v8 argument count)
type ArgumentDecl = (TokenStream2, TokenStream2, usize);
fn codegen_args(
core: &TokenStream2,
f: &syn::ItemFn,
rust_i0: usize, // Index of first generic arg in rust
v8_i0: usize, // Index of first generic arg in v8/js
) -> ArgumentDecl {
let inputs = &f.sig.inputs.iter().skip(rust_i0).enumerate();
let ident_seq: TokenStream2 = inputs
.clone()
.map(|(i, _)| format!("arg_{i}"))
.collect::<Vec<_>>()
.join(", ")
.parse()
.unwrap();
let decls: TokenStream2 = inputs
.clone()
.map(|(i, arg)| {
codegen_arg(core, arg, format!("arg_{i}").as_ref(), v8_i0 + i)
})
.collect();
(decls, ident_seq, inputs.len())
}
fn codegen_arg(
core: &TokenStream2,
arg: &syn::FnArg,
name: &str,
idx: usize,
) -> TokenStream2 {
let ident = quote::format_ident!("{name}");
let (pat, ty) = match arg {
syn::FnArg::Typed(pat) => {
if is_optional_fast_callback_option(&pat.ty) {
return quote! { let #ident = None; };
}
(&pat.pat, &pat.ty)
}
_ => unreachable!(),
};
// Fast path if arg should be skipped
if matches!(**pat, syn::Pat::Wild(_)) {
return quote! { let #ident = (); };
}
// Fast path for `String`
if is_string(&**ty) {
return quote! {
let #ident = match #core::v8::Local::<#core::v8::String>::try_from(args.get(#idx as i32)) {
Ok(v8_string) => #core::serde_v8::to_utf8(v8_string, scope),
Err(_) => {
return #core::_ops::throw_type_error(scope, format!("Expected string at position {}", #idx));
}
};
};
}
// Fast path for `Option<String>`
if is_option_string(&**ty) {
return quote! {
let #ident = match #core::v8::Local::<#core::v8::String>::try_from(args.get(#idx as i32)) {
Ok(v8_string) => Some(#core::serde_v8::to_utf8(v8_string, scope)),
Err(_) => None
};
};
}
// Fast path for &/&mut [u8] and &/&mut [u32]
match is_ref_slice(&**ty) {
None => {}
Some(SliceType::U32Mut) => {
let blck = codegen_u32_mut_slice(core, idx);
return quote! {
let #ident = #blck;
};
}
Some(_) => {
let blck = codegen_u8_slice(core, idx);
return quote! {
let #ident = #blck;
};
}
}
// Otherwise deserialize it via serde_v8
quote! {
let #ident = args.get(#idx as i32);
let #ident = match #core::serde_v8::from_v8(scope, #ident) {
Ok(v) => v,
Err(err) => {
let msg = format!("Error parsing args at position {}: {}", #idx, #core::anyhow::Error::from(err));
return #core::_ops::throw_type_error(scope, msg);
}
};
}
}
fn codegen_u8_slice(core: &TokenStream2, idx: usize) -> TokenStream2 {
quote! {{
let value = args.get(#idx as i32);
match #core::v8::Local::<#core::v8::ArrayBuffer>::try_from(value) {
Ok(b) => {
// Handles detached buffers.
let byte_length = b.byte_length();
let store = b.data() as *mut u8;
// SAFETY: rust guarantees that lifetime of slice is no longer than the call.
unsafe { ::std::slice::from_raw_parts_mut(store, byte_length) }
},
Err(_) => {
if let Ok(view) = #core::v8::Local::<#core::v8::ArrayBufferView>::try_from(value) {
let len = view.byte_length();
let offset = view.byte_offset();
let buffer = match view.buffer(scope) {
Some(v) => v,
None => {
return #core::_ops::throw_type_error(scope, format!("Expected ArrayBufferView at position {}", #idx));
}
};
let store = buffer.data() as *mut u8;
// SAFETY: rust guarantees that lifetime of slice is no longer than the call.
unsafe { ::std::slice::from_raw_parts_mut(store.add(offset), len) }
} else {
return #core::_ops::throw_type_error(scope, format!("Expected ArrayBufferView at position {}", #idx));
}
}
}}
}
}
fn codegen_u32_mut_slice(core: &TokenStream2, idx: usize) -> TokenStream2 {
quote! {
if let Ok(view) = #core::v8::Local::<#core::v8::Uint32Array>::try_from(args.get(#idx as i32)) {
let (offset, len) = (view.byte_offset(), view.byte_length());
let buffer = match view.buffer(scope) {
Some(v) => v,
None => {
return #core::_ops::throw_type_error(scope, format!("Expected Uint32Array at position {}", #idx));
}
};
let store = buffer.data() as *mut u8;
// SAFETY: buffer from Uint32Array. Rust guarantees that lifetime of slice is no longer than the call.
unsafe { ::std::slice::from_raw_parts_mut(store.add(offset) as *mut u32, len / 4) }
} else {
return #core::_ops::throw_type_error(scope, format!("Expected Uint32Array at position {}", #idx));
}
}
}
fn codegen_sync_ret(
core: &TokenStream2,
output: &syn::ReturnType,
) -> TokenStream2 {
if is_void(output) {
return quote! {};
}
if is_u32_rv(output) {
return quote! {
rv.set_uint32(result as u32);
};
}
// Optimize Result<(), Err> to skip serde_v8 when Ok(...)
let ok_block = if is_unit_result(output) {
quote! {}
} else if is_u32_rv_result(output) {
quote! {
rv.set_uint32(result as u32);
}
} else {
quote! {
match #core::serde_v8::to_v8(scope, result) {
Ok(ret) => rv.set(ret),
Err(err) => #core::_ops::throw_type_error(
scope,
format!("Error serializing return: {}", #core::anyhow::Error::from(err)),
),
};
}
};
if !is_result(output) {
return ok_block;
}
quote! {
match result {
Ok(result) => {
#ok_block
},
Err(err) => {
let exception = #core::error::to_v8_error(scope, op_state.get_error_class_fn, &err);
scope.throw_exception(exception);
},
};
}
}
fn is_void(ty: impl ToTokens) -> bool {
tokens(ty).is_empty()
}
fn is_result(ty: impl ToTokens) -> bool {
let tokens = tokens(ty);
if tokens.trim_start_matches("-> ").starts_with("Result <") {
return true;
}
// Detect `io::Result<...>`, `anyhow::Result<...>`, etc...
// i.e: Result aliases/shorthands which are unfortunately "opaque" at macro-time
match tokens.find(":: Result <") {
Some(idx) => !tokens.split_at(idx).0.contains('<'),
None => false,
}
}
fn is_string(ty: impl ToTokens) -> bool {
tokens(ty) == "String"
}
fn is_option_string(ty: impl ToTokens) -> bool {
tokens(ty) == "Option < String >"
}
enum SliceType {
U8,
U8Mut,
U32Mut,
}
fn is_ref_slice(ty: impl ToTokens) -> Option<SliceType> {
if is_u8_slice(&ty) {
return Some(SliceType::U8);
}
if is_u8_slice_mut(&ty) {
return Some(SliceType::U8Mut);
}
if is_u32_slice_mut(&ty) {
return Some(SliceType::U32Mut);
}
None
}
fn is_u8_slice(ty: impl ToTokens) -> bool {
tokens(ty) == "& [u8]"
}
fn is_u8_slice_mut(ty: impl ToTokens) -> bool {
tokens(ty) == "& mut [u8]"
}
fn is_u32_slice_mut(ty: impl ToTokens) -> bool {
tokens(ty) == "& mut [u32]"
}
fn is_optional_fast_callback_option(ty: impl ToTokens) -> bool {
tokens(&ty).contains("Option < & mut FastApiCallbackOptions")
}
/// Detects if the type can be set using `rv.set_uint32` fast path
fn is_u32_rv(ty: impl ToTokens) -> bool {
["u32", "u8", "u16"].iter().any(|&s| tokens(&ty) == s) || is_resource_id(&ty)
}
/// Detects if the type is of the format Result<u32/u8/u16, Err>
fn is_u32_rv_result(ty: impl ToTokens) -> bool {
is_result(&ty)
&& (tokens(&ty).contains("Result < u32")
|| tokens(&ty).contains("Result < u8")
|| tokens(&ty).contains("Result < u16")
|| is_resource_id(&ty))
}
/// Detects if a type is of the form Result<(), Err>
fn is_unit_result(ty: impl ToTokens) -> bool {
is_result(&ty) && tokens(&ty).contains("Result < ()")
}
fn is_resource_id(arg: impl ToTokens) -> bool {
static RE: Lazy<Regex> =
Lazy::new(|| Regex::new(r#": (?:deno_core :: )?ResourceId$"#).unwrap());
RE.is_match(&tokens(arg))
}
fn is_mut_ref_opstate(arg: impl ToTokens) -> bool {
static RE: Lazy<Regex> =
Lazy::new(|| Regex::new(r#": & mut (?:deno_core :: )?OpState$"#).unwrap());
RE.is_match(&tokens(arg))
}
fn is_rc_refcell_opstate(arg: &syn::FnArg) -> bool {
static RE: Lazy<Regex> = Lazy::new(|| {
Regex::new(r#": Rc < RefCell < (?:deno_core :: )?OpState > >$"#).unwrap()
});
RE.is_match(&tokens(arg))
}
fn is_handle_scope(arg: &syn::FnArg) -> bool {
static RE: Lazy<Regex> = Lazy::new(|| {
Regex::new(r#": & mut (?:deno_core :: )?v8 :: HandleScope(?: < '\w+ >)?$"#)
.unwrap()
});
RE.is_match(&tokens(arg))
}
fn is_future(ty: impl ToTokens) -> bool {
tokens(&ty).contains("impl Future < Output =")
}
fn tokens(x: impl ToTokens) -> String {
x.to_token_stream().to_string()
}
fn exclude_lifetime_params(
generic_params: &Punctuated<GenericParam, Comma>,
) -> Punctuated<GenericParam, Comma> {
generic_params
.iter()
.filter(|t| !tokens(t).starts_with('\''))
.cloned()
.collect::<Punctuated<GenericParam, Comma>>()
}