DaddyFrosty/yoga
1
0
Fork 0
Code Issues 96 Pull Requests 31 Actions Packages Projects Releases 33 Wiki Activity

Build WebAssembly with SINGLE_FILE=1 (#1310)

Browse Source 
Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1310

Emscripten normally compiles a binary into a `.js` file and a `.wasm` file. The `.js` file contains a shim to load the WebAssembly file for the target platform, along with passing some environment information to the underlying assembly.

Under Node this would use APIs like `fs.readFile` and its WebAssembly APIs to load the binary. In a browser, APIs like `instantiateStreaming` are used to start downloading and compiling the binary at the same time.

This format creates many, many, headaches, and manual bundler configuration. E.g. we must tell Webpack to treat WASM files as auxilary files instead of WebAssembly, cannot use Emscripten's loader directly, and would need to add more variants of the binary, since (or Node polyfills in the browser) `-s ENVIRONMENT='web,node'` emits code that looks like `if (isNode) {require('fs')}`.

This change makes us instead pack the WebAssembly as base64 inline with the JS loader. This adds a size penalty, and means we cannot start async compilation until the entire file is present, but should work out of the box when using different bundlers and configurations, and the size is small enough where it likely makes sense to inline into the bundle anyway.

There is a [proposal for integration of WebAssembly and ES Modules](https://github.com/WebAssembly/esm-integration/tree/main/proposals/esm-integration) that Node has experimental support for, and bundlers are veering towards supporting. It is the eventual solution we should target, but does not seem mature enough yet. E.g. WebPack [does not support](https://github.com/webpack/webpack/issues/11893) WebAssembly import objects, and will instead try to import each of the named imports as modules.

Reviewed By: rozele

Differential Revision: D46884398

fbshipit-source-id: a1c93c122c255b913f426bfb6bdb38fd9f9dfd41
This commit is contained in:
Nick Gerleman
2023-06-21 17:18:26 -07:00
committed by Facebook GitHub Bot
parent 8c8235cfcf
commit b8a0240aaf
1 changed files with 2 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
javascript/CMakeLists.txt
View File

@@ -64,9 +64,11 @@ target_link_options(asmjs-async PUBLIC
add_executable(wasm-sync $<TARGET_OBJECTS:yogaObjLib>)
target_link_options(wasm-sync PUBLIC
"SHELL:-s WASM=1"
"SHELL:-s SINGLE_FILE=1"
"SHELL:-s WASM_ASYNC_COMPILATION=0")
add_executable(wasm-async $<TARGET_OBJECTS:yogaObjLib>)
target_link_options(wasm-async PUBLIC
"SHELL:-s WASM=1"
"SHELL:-s SINGLE_FILE=1"
"SHELL:-s WASM_ASYNC_COMPILATION=1")