WebAssembly - post MVP features and goals

Slides for a talk presented at ParisJS meetup, link to the talk: https://www.youtube.com/watch?v=nOG0lHpRxQ8

Topics:
- WebAssembly working group
- Threads
- WebAssembly runtime performance
- WebAssembly load perfomrnace
- High-level language features

Transcript

1. WebAssembly post MVP features and goals
2. Elia Maino Software Engineer @eliamain
3. WASM MVP 2017
4. emscripten C/C++ code JS (asm.js)
5. Any code Agnostic Compile target For a virtual machine
6. WASM
7. WASM Fast Browser security Memory management execution load
8. WASM MVP
9. WASM MVP Was it the final version? Is it feature complete?
10. WASM MVP Works fine for some application Not enough for other ones
11. We need more https://github.com/WebAssembly/design/blob/master/FutureFeatures.md https://github.com/WebAssembly/design
13. Features proposals
14. The mission of the WebAssembly Working Group is to standardize a size- and load-time-efficient format and execution environment, allowing compilation to the web with consistent behavior across a variety of implementations.
15. Features proposals WebAssembly W3C process https://github.com/WebAssembly/meetings/blob/master/process/phases.md “ A feature is a substantial change to WebAssembly, such that it for example requires additional opcodes, types, tests, or module sections. ”
16. WebAssembly W3C process https://github.com/WebAssembly/meetings/blob/master/process/phases.md Pre-proposal Feature proposal Proposed Spec Text Available Implementation Phase Standardize the feature Feature is standardized
17. Performance
18. Performance MULTI THREADING Take advantage of multi cores architectures https://github.com/WebAssembly/threads Status: Proposed spec text available
19. Performance MULTI THREADING Status: Proposed spec text available Experimental feature https://developers.google.com/web/updates/2018/10/wasm-threads Security issues with SharedArrayBuffer https://github.com/emscripten-core/emscripten/wiki/Pthreads-with-WebAssembly https://blog.mozilla.org/security/2018/01/03/mitigations-landing-new-class-timing- attack/
20. https://web.dev/earth-webassembly/
21. https://github.com/rhysd/vim.wasm
22. Please access from desktop Chrome, Firefox, Safari or Chromium based browsers since this project uses SharedArrayBuffer and Atomics. On Firefox or Safari, feature flags (javascript.options.shared_memory for Firefox) must be enabled for now.
24. Performance SIMD Single Instruction Multiple Data: process things in parallel https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md Status: Feature proposal
25. VS data parallelism concurrency (multithreading) (SIMD)
26. data parallelism concurrency
27. Performance 64-bit addressing Remove the artificial limitation of addressable space From WebAssembly https://github.com/WebAssembly/design/blob/master/FutureFeatures.md#linear- memory-bigger-than-4-gib Status: Pre-proposal
28. Language Features FRAMEWORKS COMPILE TO-JS
29. Language Features GARBAGE COLLECTOR EXCEPTION HANDLING DEBUGGING TAIL CALLS
30. Language Features GARBAGE COLLECTOR Add an integration with the browser garbage collector JS needs a way to describe an object fixed structure Typed objects: https://github.com/tschneidereit/proposal-typed-objects WebAssembly GC: https://github.com/WebAssembly/gc Status: Feature proposal
31. Language Features EXCEPTION HANDLING Proper support for languages exceptions By default disabled in WebAssembly when compiling (there’s an heavy polyfill) Hard to handle the case when WASM calls some JS code which throws an exception :/
32. Language Features EXCEPTION HANDLING Proper support for languages exceptions Status: Feature proposal https://github.com/WebAssembly/exception-handling
33. Language Features DEBUGGING DevTools for JS debugging are great Support a similar level of debugging for WebAssembly https://github.com/WebAssembly/debugging
34. Loadtime ⏳
35. Why is that even needed?
36. Why is that even needed? PREDICTABLE PERFORMANCE CODE IS COMPILED AHEAD OF TIME
37. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded
38. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded .wasm browser compiler
39. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
40. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
41. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
42. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
43. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
44. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
45. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded .wasm browser compiler
46. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
47. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
48. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
49. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded browser compiler
50. Loadtime STREAMING COMPILATION Compile a WebAssembly file while it’s still being downloaded Status: Shipped (depends on the browser)
51. Loadtime STREAMING COMPILATION Status: Shipped (depends on the browser) https://v8.dev/blog/v8-release-65 Shipped https://hacks.mozilla.org/2018/01/making-webassembly-even-faster-firefoxs-new- streaming-and-tiering-compiler/ Shipped
52. Loadtime TIERED COMPILATION Having more than one compiler in action
53. Loadtime TIERED COMPILATION Having more than one compiler in action .wasm browser compiler
54. Loadtime TIERED COMPILATION Having more than one compiler in action browser compiler
55. Loadtime TIERED COMPILATION Having more than one compiler in action browser compiler
56. Loadtime TIERED COMPILATION Having more than one compiler in action browser basic compiler optimizing compiler
57. Loadtime TIERED COMPILATION Having more than one compiler in action browser basic compiler optimizing compiler ✨
58. Loadtime TIERED COMPILATION Having more than one compiler in action browser optimizing compiler ✨ basic compiler
59. Loadtime TIERED COMPILATION Having more than one compiler in action Status: Shipped (depends on the browser)
60. Loadtime TIERED COMPILATION Status: Shipped (depends on the browser) https://v8.dev/blog/liftoff https://hacks.mozilla.org/2018/01/making-webassembly-even-faster-firefoxs-new- streaming-and-tiering-compiler/ https://github.com/CraneStation/cranelift https://webkit.org/blog/7691/webassembly/ (OMG! BBQ!)
61. Loadtime Implicit HTTP caching Take advantage of WebAssembly predictable compilation output Using the already compiled machine code Instead of the .wasm file Status: Work in progress
62. Loadtime Implicit HTTP caching Status: Work in progress https://v8.dev/blog/wasm-code-caching Work in progress https://bugzilla.mozilla.org/show_bug.cgi?id=1487113 Shipped
63. Modules
64. Modules Calls between JS and WASM Calls between the two environments where working in the MVP But weren’t optimized to be fast https://hacks.mozilla.org/2018/10/calls-between-javascript-and-webassembly-are-finally-fast- %f0%9f%8e%89/ Status: Shipped (in )
66. Modules Data exchange between JS and WASM WASM only understands numbers, add a way to pass/ reference objects too https://github.com/WebAssembly/reference-types/blob/master/proposals/reference-types/ Overview.md Status: Implementation Phase
67. Modules ES Modules integration Load WebAssembly from a JavaScript import statement, or a <script type=module> tag https://github.com/WebAssembly/esm-integration/tree/master/proposals/esm- integration Status: Feature proposal
69. is WebAssembly only useful in the browser?
70. browsers portability security
72. portability security
74. WebAssembly System Interface https://wasi.dev/ https://hacks.mozilla.org/2019/03/standardizing-wasi-a-webassembly-system-interface/ https://github.com/WebAssembly/WASI
75. Threads GC SIMD Modules Tiered compilation Exceptions Debugging ✨
76. Thank you! @eliamain