tc39/ecmascript_simd

SIMD numeric type for EcmaScript

JavaScript

546

485 commits

updated Sep 7, 2018

See the code

See what people are saying

SourceMessageScoreDate

The JavaScript Midlife Crisis

1) Google Sheets use case Long story short they are comparing the performance of server-side Java to client-side JS (Java transpiled through GWT/J2CL). So something like: Java -> Hotspot -> native vs Java -> GWT/J2CL -> JS -> V8 (in Chrome) -> native Apples to oranges. They then used J2CL (I…

0

Sep 24, 2026

README

SIMD.js

===============

SIMD.js has been taken out of active development in TC39 and removed from Stage 3, and is not being pursued by web browsers for implementation. SIMD operations exposed to the web are under active development within WebAssembly, with operations based on the SIMD.js operations. With WebAssembly in advanced development or shipping in multiple browsers, it seems like an adequate vehicle to subsume asm.js use cases, which are judged to be the broader cases. Although some developers have expressed interest in using SIMD.js outside of asm.js, implementers have found that implementing and optimizing for this case reliably creates a lot of complexity, and have made the decision to focus instead on delivering WebAssembly and SIMD instructions in WASM.

See https://github.com/WebAssembly/simd for current development.

This repository retains a historical snapshot of the SIMD.js specification work:

  • The authoritative API reference documentation is generated from tc39/spec.html. You can view a rendered copy at http://tc39.github.io/ecmascript_simd/ .
  • A polyfill at src/ecmascript_simd.js, which can't implement value semantics, but includes a correct implementation of all functions
  • Extensive tests at src/ecmascript_simd_tests.js, which can be run using other files in src/. Benchmarks and example code live in the same directory.
  • A presentation explaining the motivation and outlining the approach at tc39/SIMD-128 TC-39.pdf

Contributors

johnmccutchan

135 commits

littledan

114 commits

sunfishcode

95 commits

P-Jensen

42 commits

tc39/ecmascript_simd

SIMD numeric type for EcmaScript

JavaScript

546

485 commits

updated Sep 7, 2018

See the code

See what people are saying

SourceMessageScoreDate

The JavaScript Midlife Crisis

1) Google Sheets use case Long story short they are comparing the performance of server-side Java to client-side JS (Java transpiled through GWT/J2CL). So something like: Java -> Hotspot -> native vs Java -> GWT/J2CL -> JS -> V8 (in Chrome) -> native Apples to oranges. They then used J2CL (I…

0

Sep 24, 2026

README

SIMD.js

===============

SIMD.js has been taken out of active development in TC39 and removed from Stage 3, and is not being pursued by web browsers for implementation. SIMD operations exposed to the web are under active development within WebAssembly, with operations based on the SIMD.js operations. With WebAssembly in advanced development or shipping in multiple browsers, it seems like an adequate vehicle to subsume asm.js use cases, which are judged to be the broader cases. Although some developers have expressed interest in using SIMD.js outside of asm.js, implementers have found that implementing and optimizing for this case reliably creates a lot of complexity, and have made the decision to focus instead on delivering WebAssembly and SIMD instructions in WASM.

See https://github.com/WebAssembly/simd for current development.

This repository retains a historical snapshot of the SIMD.js specification work:

  • The authoritative API reference documentation is generated from tc39/spec.html. You can view a rendered copy at http://tc39.github.io/ecmascript_simd/ .
  • A polyfill at src/ecmascript_simd.js, which can't implement value semantics, but includes a correct implementation of all functions
  • Extensive tests at src/ecmascript_simd_tests.js, which can be run using other files in src/. Benchmarks and example code live in the same directory.
  • A presentation explaining the motivation and outlining the approach at tc39/SIMD-128 TC-39.pdf

Contributors

johnmccutchan

135 commits

littledan

114 commits

sunfishcode

95 commits

P-Jensen

42 commits

Languages

JavaScript

65.2%

HTML

34.8%