mirror of
https://github.com/fluencelabs/wasm-bindgen
synced 2025-06-15 05:51:23 +00:00
Optimize JsValue::{from_bool, undefined, null} constructors (#220)
This commit optimizes constructing an instance of `JsValue` which is one of `null`, `undefined`, `true`, or `false`. These are commonly created on the Rust side of things and since there's only a limited set of values we can easily prepopulate the global slab with a few entries and use hardcoded indices to refer to these constants. This should avoid the need to travel into JS to insert a `null` or and `undefined` into the global slab.
This commit is contained in:
Alex Crichton
GitHub
@ -690,17 +690,23 @@ impl<'a> Context<'a> {
|
||||
if !self.exposed_globals.insert("slab") {
|
||||
return;
|
||||
}
|
||||
self.global(&format!("let slab = [];"));
|
||||
let initial_values = [
|
||||
"{ obj: null }",
|
||||
"{ obj: undefined }",
|
||||
"{ obj: true }",
|
||||
"{ obj: false }",
|
||||
];
|
||||
self.global(&format!("let slab = [{}];", initial_values.join(", ")));
|
||||
if self.config.debug {
|
||||
self.export("assertSlabEmpty", "
|
||||
function() {
|
||||
for (let i = 0; i < slab.length; i++) {
|
||||
self.export("assertSlabEmpty", &format!("
|
||||
function() {{
|
||||
for (let i = {}; i < slab.length; i++) {{
|
||||
if (typeof(slab[i]) === 'number')
|
||||
continue;
|
||||
throw new Error('slab is not currently empty');
|
||||
}
|
||||
}
|
||||
");
|
||||
}}
|
||||
}}
|
||||
", initial_values.len()));
|
||||
}
|
||||
}
|
||||
|
||||
@ -708,8 +714,9 @@ impl<'a> Context<'a> {
|
||||
if !self.exposed_globals.insert("slab_next") {
|
||||
return;
|
||||
}
|
||||
self.expose_global_slab();
|
||||
self.global(&format!("
|
||||
let slab_next = 0;
|
||||
let slab_next = slab.length;
|
||||
"));
|
||||
}
|
||||
|
||||
|
||||
41
package-lock.json
generated
41
package-lock.json
generated
@ -2717,8 +2717,7 @@
|
||||
"ansi-regex": {
|
||||
"version": "2.1.1",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"aproba": {
|
||||
"version": "1.2.0",
|
||||
@ -2739,14 +2738,12 @@
|
||||
"balanced-match": {
|
||||
"version": "1.0.0",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"brace-expansion": {
|
||||
"version": "1.1.11",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true,
|
||||
"requires": {
|
||||
"balanced-match": "^1.0.0",
|
||||
"concat-map": "0.0.1"
|
||||
@ -2761,20 +2758,17 @@
|
||||
"code-point-at": {
|
||||
"version": "1.1.0",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"concat-map": {
|
||||
"version": "0.0.1",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"console-control-strings": {
|
||||
"version": "1.1.0",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"core-util-is": {
|
||||
"version": "1.0.2",
|
||||
@ -2891,8 +2885,7 @@
|
||||
"inherits": {
|
||||
"version": "2.0.3",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"ini": {
|
||||
"version": "1.3.5",
|
||||
@ -2904,7 +2897,6 @@
|
||||
"version": "1.0.0",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true,
|
||||
"requires": {
|
||||
"number-is-nan": "^1.0.0"
|
||||
}
|
||||
@ -2919,7 +2911,6 @@
|
||||
"version": "3.0.4",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true,
|
||||
"requires": {
|
||||
"brace-expansion": "^1.1.7"
|
||||
}
|
||||
@ -2927,14 +2918,12 @@
|
||||
"minimist": {
|
||||
"version": "0.0.8",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"minipass": {
|
||||
"version": "2.2.4",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true,
|
||||
"requires": {
|
||||
"safe-buffer": "^5.1.1",
|
||||
"yallist": "^3.0.0"
|
||||
@ -2953,7 +2942,6 @@
|
||||
"version": "0.5.1",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true,
|
||||
"requires": {
|
||||
"minimist": "0.0.8"
|
||||
}
|
||||
@ -3034,8 +3022,7 @@
|
||||
"number-is-nan": {
|
||||
"version": "1.0.1",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"object-assign": {
|
||||
"version": "4.1.1",
|
||||
@ -3047,7 +3034,6 @@
|
||||
"version": "1.4.0",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true,
|
||||
"requires": {
|
||||
"wrappy": "1"
|
||||
}
|
||||
@ -3133,8 +3119,7 @@
|
||||
"safe-buffer": {
|
||||
"version": "5.1.1",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"safer-buffer": {
|
||||
"version": "2.1.2",
|
||||
@ -3170,7 +3155,6 @@
|
||||
"version": "1.0.2",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true,
|
||||
"requires": {
|
||||
"code-point-at": "^1.0.0",
|
||||
"is-fullwidth-code-point": "^1.0.0",
|
||||
@ -3190,7 +3174,6 @@
|
||||
"version": "3.0.1",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true,
|
||||
"requires": {
|
||||
"ansi-regex": "^2.0.0"
|
||||
}
|
||||
@ -3234,14 +3217,12 @@
|
||||
"wrappy": {
|
||||
"version": "1.0.2",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
},
|
||||
"yallist": {
|
||||
"version": "3.0.2",
|
||||
"bundled": true,
|
||||
"dev": true,
|
||||
"optional": true
|
||||
"dev": true
|
||||
}
|
||||
}
|
||||
},
|
||||
|
||||
23
src/lib.rs
23
src/lib.rs
@ -60,6 +60,12 @@ pub struct JsValue {
|
||||
idx: u32,
|
||||
}
|
||||
|
||||
const JSIDX_NULL: u32 = 0;
|
||||
const JSIDX_UNDEFINED: u32 = 2;
|
||||
const JSIDX_TRUE: u32 = 4;
|
||||
const JSIDX_FALSE: u32 = 6;
|
||||
const JSIDX_RESERVED: u32 = 8;
|
||||
|
||||
impl JsValue {
|
||||
/// Creates a new JS value which is a string.
|
||||
///
|
||||
@ -86,23 +92,17 @@ impl JsValue {
|
||||
/// This function creates a JS object representing a boolean (a heap
|
||||
/// allocated boolean) and returns a handle to the JS version of it.
|
||||
pub fn from_bool(b: bool) -> JsValue {
|
||||
unsafe {
|
||||
JsValue { idx: __wbindgen_boolean_new(b as u32) }
|
||||
}
|
||||
JsValue { idx: if b { JSIDX_TRUE } else { JSIDX_FALSE } }
|
||||
}
|
||||
|
||||
/// Creates a new JS value representing `undefined`.
|
||||
pub fn undefined() -> JsValue {
|
||||
unsafe {
|
||||
JsValue { idx: __wbindgen_undefined_new() }
|
||||
}
|
||||
JsValue { idx: JSIDX_UNDEFINED }
|
||||
}
|
||||
|
||||
/// Creates a new JS value representing `null`.
|
||||
pub fn null() -> JsValue {
|
||||
unsafe {
|
||||
JsValue { idx: __wbindgen_null_new() }
|
||||
}
|
||||
JsValue { idx: JSIDX_NULL }
|
||||
}
|
||||
|
||||
/// Creates a new JS symbol with the optional description specified.
|
||||
@ -331,9 +331,14 @@ impl Clone for JsValue {
|
||||
impl Drop for JsValue {
|
||||
fn drop(&mut self) {
|
||||
unsafe {
|
||||
// if the first bit is set then this is a stack value, so we for
|
||||
// sure need to drop it. Otherwise if this is one of the special
|
||||
// reserved values there's no need to drop it.
|
||||
if (self.idx & 1) == 1 || self.idx >= JSIDX_RESERVED {
|
||||
__wbindgen_object_drop_ref(self.idx);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Wrapper type for imported statics.
|
||||
|
||||
Reference in New Issue
Block a user