perf(web): optimize single pass utf8 decoding #16593
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| let stream = false; | ||
| if (options !== undefined) { | ||
| options = webidl.converters.TextDecodeOptions(options, { | ||
| prefix, | ||
| context: "Argument 2", | ||
| }); | ||
| stream = options.stream; | ||
| } |
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We should come up with a general improvement in webidl for cases like this. I think the optimal way would require new Function codegen.
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For what it's worth, Evan (Discord) had been saying that for over a year. The entire WebIDL bindings setup should be via JiT-compiled codegen.
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yeah :(
never too late though
| input.buffer, | ||
| input.byteOffset, | ||
| input.byteLength, |
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Well... now these are all polymorphic...
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wasn't this already the case before this patch?
| ObjectPrototypeIsPrototypeOf( | ||
| SharedArrayBuffer.prototype, |
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| ObjectPrototypeIsPrototypeOf( | |
| SharedArrayBuffer.prototype, | |
| ObjectPrototypeIsPrototypeOf( | |
| SharedArrayBufferPrototype, |
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can we please defer these primordials changes? I don't want to make the code any slower
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Sure; I'll introduce these next month, myself.
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lets see what others think. i personally don't like primordials in fast paths for mitigating a hypothetical case. Node.js has also removed primoridals in hot paths previously nodejs/node#38248
| if ( | ||
| ObjectPrototypeIsPrototypeOf( | ||
| SharedArrayBuffer.prototype, | ||
| input.buffer, | ||
| input || input.buffer, |
- [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.
https://encoding.spec.whatwg.org/#dom-textdecoder-decode
Object.assignwhen options is undefined.