serializer.unstable_inlineDependencyMap: Add opt-in serialise-time module id inlining to the serialiser (#1786) - #1786
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serializer.unstable_inlineDependencyMap: Add opt-in serialise-time module id inlining to the serialiser (#1786)#1786robhogan wants to merge 2 commits into
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…g helper Summary: Upstream `inlineModuleIdReferences`, a pure string helper, from Metro-Buck to the OSS serialiser. This utility replaces `dependencyMapReservedName[i]` references in a module body with the resolved numeric module ID of dependency `i`, without any reparse or AST manipulation, with padding to preserve source map correctness. The safety of pure string replacement is guaranteed by `unstable_dependencyMapReservedName` (optional, enforces that that string cannot appear in user code) - this utility will throw if that's not set. In Metro-Buck, this powers an a runtime optimisation that replaces an array access with the literal. Immediately, this saves a bunch of array accesses during startup (especially if `inlineRequires` is disabled), and provides a modest bundle size reduction. On top of that, it unlocks `$SHBuiltin`-based optimisations (`unstable_enableStaticHermesOptimizedRequire`), which currently rely on matching a `require(<literal>)`. The OSS serialiser itself is not yet wired to use the helper; that opt-in wiring lands in the next diff. Changelog: [Internal] Reviewed By: huntie Differential Revision: D112353888
…dule id inlining to the serialiser (#1786) Summary: Wires the `inlineModuleIdReferences` helper (previous diff) into the OSS serialiser behind a new opt-in `serializer.unstable_inlineDependencyMap`, porting this Metro-Buck optimisation to core. When `serializer.unstable_inlineDependencyMap` AND `transformer.unstable_dependencyMapReservedName` is set, each module body has its `<reservedName>[i]` references replaced with the resolved numeric module ID (right-padded to preserve source-map columns), and the dependency-map array argument is dropped from the `__d(...)` call (where it is empty AND the last argument). For dev bundles, a `null` keeps that slot occupied so the verbose-name argument stays in position. With the flag off, output is unchanged. Threading: - `SerializerConfigT` (+ default) gains `unstable_inlineDependencyMap`. - `SerializerOptions` gains optional `unstable_inlineDependencyMap` and `dependencyMapReservedName`. - `Server.js` populates both at all three serialiser-options construction sites from resolved config (the reserved name is already resolved at serialise time). - `baseJSBundle` -> `processModules` -> `wrapModule`/`getModuleParams` thread the options. Changelog: ``` - **[Experimental]**: Add `serializer.unstable_inlineDependencyMap` for an opt-in runtime optimisation. ``` Reviewed By: motiz88, huntie Differential Revision: D112353887
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Summary:
Wires the
inlineModuleIdReferenceshelper (previous diff) into the OSS serialiser behind a new opt-inserializer.unstable_inlineDependencyMap, porting this Metro-Buck optimisation to core.When
serializer.unstable_inlineDependencyMapANDtransformer.unstable_dependencyMapReservedNameis set, each module body has its<reservedName>[i]references replaced with the resolved numeric module ID (right-padded to preserve source-map columns), and the dependency-map array argument is dropped from the__d(...)call (where it is empty AND the last argument).For dev bundles, a
nullkeeps that slot occupied so the verbose-name argument stays in position.With the flag off, output is unchanged.
Threading:
SerializerConfigT(+ default) gainsunstable_inlineDependencyMap.SerializerOptionsgains optionalunstable_inlineDependencyMapanddependencyMapReservedName.Server.jspopulates both at all three serialiser-options construction sites from resolved config (the reserved name is already resolved at serialise time).baseJSBundle->processModules->wrapModule/getModuleParamsthread the options.Changelog:
Reviewed By: motiz88, huntie
Differential Revision: D112353887