fix(code-splitting): make strict transitive init registration deterministic and constant-time - #10320
Merged
Conversation
Merging this PR will not alter performance
Comparing 
Footnotes
|
graphite-app
Bot
force-pushed
the
codex/vite-chunk-execution-order-plan
branch
from
July 17, 2026 08:56
2ee23cc to
1d86ffe
Compare
hyfdev
force-pushed
the
codex/strict-transitive-init-determinism
branch
from
July 20, 2026 14:07
56f76bc to
d427f05
Compare
✅ Deploy Preview for rolldown-rs canceled.
|
hyfdev
force-pushed
the
codex/strict-transitive-init-determinism
branch
from
July 22, 2026 03:38
d427f05 to
4039bf3
Compare
IWANABETHATGUY
approved these changes
Jul 22, 2026
Member
Author
Merge activity
|
…nistic and constant-time (#10320) ## Summary Two independent, cheap fixes to the strict-execution-order cross-chunk link pass (review items 3 and 4): - **Cross-target determinism.** `add_transitive_esm_init_depended_symbols` iterated an `FxHashMap` via `.values()`, whose bucket order follows FxHash layout. FxHash is unseeded but hashes differently on 32-bit vs 64-bit, so that order — which flows into the chunk's `depended_symbols` `FxIndexSet` and thence into imported-symbol rename order (the `$1`/`$2` suffixes) in `deconflict_chunk_symbols` — could diverge between native and wasm32/WASI builds. Now iterated sorted by the owning `StmtInfoIdx`, pinning one order everywhere. It is the single hash-ordered site three review passes converged on; every other hash-ordered effect is already sorted before use. - **Quadratic strict-mode hot loop.** `module_is_in_live_chunk` did a linear `chunk.modules.contains` scan, called for every canonical referenced symbol of every included statement under strict — quadratic on large chunks. Replaced with an O(1) `module_to_chunk` + liveness check. The O(1) rewrite is verified semantically equivalent: `add_module_to_chunk` sets `module_to_chunk[m]` and pushes `m` onto `c.modules` together, and every site that later removes a module from a chunk's `modules` list preserves the invariant (`module_to_chunk[m] == Some(c) && c live ⟹ c.modules ∋ m`) by pairing the removal with clearing `module_to_chunk[m]` (unused-runtime sweep), reassigning it to the destination chunk via `add_module_to_chunk` (runtime relocation, runtime→target merge, `apply_common_chunk_merges`), or marking the emptied chunk `Removed`. No site leaves `module_to_chunk` pointed at a still-live chunk that no longer contains the module, so no removed-module set is needed. The invariant is documented in the function's doc comment. ## Behavior / snapshot impact **None.** Zero fixture snapshot changes. The determinism fix is invisible on native 64-bit (its value is native-vs-wasm parity, which the native suite cannot exercise); the O(1) change is a pure performance rewrite with identical results. ## Validation - `cargo test -p rolldown` — 1868 passed; snapshot-stable (zero deltas). The only failures are 5 pre-existing environmental ones unrelated to this change (`cjs_module_lexer_compat` ×3 and `npm_packages/util_deprecate` need an installed `cjs-module-lexer`; `test262` needs the test262 submodule). - `cargo fmt --all --check` — clean. - `cargo clippy -p rolldown --all-targets -- -D warnings` — clean. --- Follow-up to #10104; addresses the two "cheap pre-merge fixes" (items 3 and 4) from the review discussion: #10104 (comment)
graphite-app
Bot
force-pushed
the
codex/strict-transitive-init-determinism
branch
from
July 22, 2026 06:58
4039bf3 to
1ed58f4
Compare
7 of 19 tasks
Merged
shulaoda
added a commit
that referenced
this pull request
Jul 29, 2026
## [1.2.1] - 2026-07-29 ### 🚀 Features - dev: support `hotUpdate` hook (#10305) by @h-a-n-a - dev: expose `disableWatcher` through the dev engine bindings (#10474) by @shulaoda - plugin: surface output-option callbacks in [PLUGIN_TIMINGS] (#10411) by @IWANABETHATGUY - `import.meta.ROLLDOWN_FILE_URL_<referenceId>_<urlId>` support to pass context to `resolveFileUrl` hook (#10297) by @sapphi-red - dev: skip the HMR update when a module's rebuilt output is unchanged (#10333) by @h-a-n-a - code-splitting: wrap strict execution order modules on demand (#10104) by @hyfdev - support `import.meta.ROLLDOWN_FILE_URL_*` (#10296) by @sapphi-red - implement `resolveFileUrl` plugin hook (#10291) by @sapphi-red - magic-string: support storeName on overwrite/update (#10312) by @IWANABETHATGUY ### 🐛 Bug Fixes - external: keep `__toESM` when the importing module is tree-shaken (#10516) by @IWANABETHATGUY - dev: resolve re-exports from externals through a real import (#10489) by @tbvjaos510 - code-splitting: route CJS barrel initialization per consumer (#10488) by @hyfdev - error: align filename-pattern diagnostics with Rollup's wording (#10501) by @IWANABETHATGUY - plugin: validate emitted prebuilt-chunk file names (#10399) by @IWANABETHATGUY - code-splitting: point a two-argument dynamic import at the chunk that holds the module (#10479) by @hyfdev - common: align is_path_fragment with Rollup's isPathFragment (#10398) by @IWANABETHATGUY - code-splitting: never name an internal chunk export `then` (#10480) by @hyfdev - code-splitting: avoid creating call-site-triggered entry facades (#10485) by @hyfdev - code-splitting: collect top-level eager order reasons in every strict build (#10463) by @hyfdev - code-splitting: let a cross-chunk dynamic importer carry the order trigger (#10456) by @hyfdev - code-splitting: avoid the dynamic-entry facade when the same-chunk collapse carries the trigger (#10433) by @hyfdev - binding: forward resolveId options.kind to callable builtin plugins (#10440) by @martijnwalraven - dev: keep the export name of `export * as ns from` (#10476) by @tbvjaos510 - code-splitting: only split an entry facade when something else can load its chunk (#10441) by @hyfdev - code-splitting: fold the runtime chunk back after order lowering (#10414) by @hyfdev - runtime: don't leave default undefined for cjs that fakes __esModule (#10453) by @IWANABETHATGUY - import-glob: escape generated string literals (#10438) by @shantanuraj - preserve-modules: don't assume every chunk mirrors a module (#10442) by @hyfdev - filter: treat missing hook inputs as non-matches, not panics (#10443) by @IWANABETHATGUY - code-splitting: keep CommonJS modules wrapped under strict execution order (#10405) by @hyfdev - code-splitting: align dynamicImports metadata with the rewritten import() specifier (#10430) by @hyfdev - dev: skip user plugin hooks for ?rolldown-lazy proxy modules (#10426) by @unknownjedi - treeshake: preserve side-effect-free spread arguments in manual-pure chains (#10432) by @IWANABETHATGUY - treeshake: preserve eagerly evaluated child effects of manual pure chains (#10427) by @Nic-Polumeyv - code-splitting: initialize pure definers behind star re-export barrels under strict execution order (#10409) by @hyfdev - resolveId: reject string `id` filters (must be a RegExp) (#10412) by @IWANABETHATGUY - code-splitting: collect eager order reasons for on-demand wrapping (#10387) by @hyfdev - rolldown: apply output.paths to CJS export-star of external modules (#10406) by @IWANABETHATGUY - dev: sourcemaps of lazily compiled chunks (#10386) by @tbvjaos510 - plugin: validate emitted file names at emitFile time (#10377) by @Nic-Polumeyv - guarantee tokio runtime release when close rejects (#10381) by @shulaoda - code-splitting: make strict transitive init registration deterministic and constant-time (#10320) by @hyfdev - pair tokio runtime acquire and release on wasm to prevent premature shutdown (#10363) by @shulaoda - don't body-demand modules from simulated facade chunk includes (#10351) by @IWANABETHATGUY - tracing: invalid RD_LOG filter and RD_LOG_OUTPUT=json no longer panic (#10343) by @Brooooooklyn - code-splitting: treat class definition-time global reads as order-sensitive (#10322) by @hyfdev - code-splitting: deconflict force-included runtime helper statements (#10336) by @hyfdev - binding: forward all missing parallel JS plugin hooks (#10345) by @Brooooooklyn - code-splitting: re-derive chunk exec order after the runtime sweep (#10334) by @hyfdev - types: add undefined to ExistingRawSourceMap optional properties (#10355) by @ocavue - magic-string: validate relocate ranges before rewiring (#10327) by @IWANABETHATGUY - add EMPTY_IMPORT_META warning for non-node CJS output (#10222) by @sapphi-red - call `resolveFileUrl` in a deterministic order (#10330) by @sapphi-red - magic-string: refuse repeated sendMagicString on a consumed instance (#10331) by @IWANABETHATGUY - magic-string: refuse to use a MagicString after sendMagicString consumed it (#10326) by @IWANABETHATGUY - magic-string: reject non-contiguous moves before rewiring the chunk list (#10311) by @IWANABETHATGUY - handle `./foo/bar` glob pattern the same as `foo/bar` (#10313) by @sapphi-red - magic-string: throw instead of panicking when append/prepend splits an edited chunk (#10301) by @IWANABETHATGUY - output: skip separator for empty hoisted functions (#10310) by @hyfdev - magic-string: don't report a change when edits cancel out (#10299) by @IWANABETHATGUY - sourcemap: map wrapped imported callees (#10288) by @hyfdev - magic-string: count positional inserts at index 0 on an empty source (#10306) by @IWANABETHATGUY - magic-string: return UTF-16 code units from length() (#10295) by @IWANABETHATGUY - output: skip separator for empty import prelude (#10289) by @hyfdev ### 🚜 Refactor - dev: make it easier to customize the runtime (#10338) by @sapphi-red - code-splitting: declare CJS carrier namespaces initializer-free (#10513) by @hyfdev - rollup-tests: avoid relying on `NODE_PATH` env var resolution (#10496) by @sapphi-red - code-splitting: derive symbol chunk ownership as pass-local link data (#10449) by @hyfdev - plugin: share asset emission helpers between copy_module and asset_module (#10450) by @Nic-Polumeyv - plugin: dedupe hook binding boilerplate (#10428) by @Nic-Polumeyv - plugin: share the oxc parse preamble between import-glob and dynamic-import-vars (#10452) by @Nic-Polumeyv - implement `GetAstBuilder` on visitor/pass types (#10424) by @overlookmotel - pass arrays to AST builder methods (#10419) by @overlookmotel - shorten AST builder code (#10418) by @overlookmotel - centralize final ESM init metadata (#10376) by @hyfdev - descriptor-based parallel-plugin detection (getParallelPluginInfo) (#10349) by @Brooooooklyn - remove AstFactory in favor of new_* construction traits (#10353) by @Boshen - enable oxc_ast's `disable_old_builder` feature (#10316) by @Boshen ### 📚 Documentation - development-guide: update config.json link line reference (#10523) by @dogledogle - clarify slash normalization for id hook filter (#10511) by @sapphi-red - code-splitting: record the thenable-namespace rule (#10502) by @hyfdev - clarify that `esmExternalRequirePlugin` must own its externals (#10439) by @TheAlexLichter - add troubleshooting entry for the @rolldown/binding-... resolution error (#10390) by @Nic-Polumeyv - add Code Splitting API reference category (#10382) by @vittorioexp ### ⚡ Performance - use VisitJsMut in JavaScript-only AST passes (#10507) by @Boshen - cache the resolved glob matcher for Id/ImporterId filters (#10410) by @IWANABETHATGUY - scope_hoisting: remove `alloc` field from `ScopeHoistingFinalizer` (#10425) by @overlookmotel - reduce string allocations (#10423) by @overlookmotel - hmr: remove unnecessary string allocations (#10422) by @overlookmotel - avoid allocating static strings via custom builder methods (#10421) by @overlookmotel - pass string literals to AST builder methods (#10420) by @overlookmotel - use VisitJs in JavaScript-only AST passes (#10396) by @Boshen - plugin: shrink erased plugin debug vtables (#10370) by @Boshen - reuse normalized path buffers (#10315) by @hyfdev ### 🧪 Testing - code-splitting: pin CJS barrel fallback triggers and flag-off equivalence (#10514) by @hyfdev - plugin: cover chunk fileName, absolute chunk name, and Windows drive names (#10400) by @IWANABETHATGUY - code-splitting: cover a single-chunk dynamic import of a wrapped module (#10505) by @hyfdev - file: remove the unused .dynamic_import fixture (#10481) by @hyfdev - treeshake: reduce manual-pure fixture to a minimal smoke test, move matrix to unit tests (#10436) by @IWANABETHATGUY - dev: run vite playgrounds under bundled dev (test-serve-bundled) (#10434) by @h-a-n-a - stop snapshots from silently hiding user code inside the runtime region (#10431) by @hyfdev - wasi: add tokio runtime lifecycle regression test (#10379) by @shulaoda - dev: expect preserved hot.data in hmr-whole-chain-dispose (#10380) by @h-a-n-a - code-splitting: pin flag-off wrapped-esm init emission (#10324) by @hyfdev - sourcemap: fix Windows-only failures in composition fixtures (#10368) by @shulaoda - generated-code: mark assert external in symbols_ns2 for deterministic output (#10339) by @hyfdev - code-splitting: cover entries-aware strict init cycle (#10307) by @hyfdev - make `just setup-vite` the only entry point that touches `vite/` (#10332) by @shulaoda - vite-tests: reuse the shared root vite checkout (#10325) by @shulaoda - test-dev-server: drop the vite submodule, track rolldown-canary (#10319) by @shulaoda - vite-tests: track the latest rolldown-canary rebased onto vite main (#10318) by @shulaoda - unify Vite in vite-test and test-dev-server (#10293) by @h-a-n-a ### ⚙️ Miscellaneous Tasks - scope the binding artifact download to `bindings-*` (#10525) by @shulaoda - deps: update napi (#10506) by @renovate[bot] - deps: update rollup submodule for tests to v4.62.3 (#10494) by @rolldown-guard[bot] - deps: upgrade oxc to 0.142.0 (#10497) by @shulaoda - deps: update test262 submodule for tests (#10495) by @rolldown-guard[bot] - deps: update github actions (#10460) by @renovate[bot] - deps: update rust crates (#10462) by @renovate[bot] - deps: update npm packages (#10461) by @renovate[bot] - metric: alert Discord when the metric workflow fails (#10447) by @IWANABETHATGUY - metric: mint a short-lived GitHub App token instead of a PAT (#10446) by @IWANABETHATGUY - repo: repair dangling CLAUDE.md symlink (#10451) by @hanayashiki - publint/package-metadata fixes and small correctness fixes (#10344) by @Brooooooklyn - deps: update dependency vite-plus to v0.2.6 (#10404) by @renovate[bot] - add Semgrep scan workflow (#10395) by @Boshen - enable Windows CI with a PR label (#10375) by @hyfdev - deps: upgrade oxc to 0.141.0 (#10373) by @camc314 - deps: update napi (#10369) by @renovate[bot] - deps: update test262 submodule for tests (#10367) by @rolldown-guard[bot] - deps: update taiki-e/install-action action to v2.83.3 (#10358) by @renovate[bot] - deps: update rust crates (#10357) by @renovate[bot] - deps: update npm packages (#10359) by @renovate[bot] - deps: update rust crate syn to v3 (#10362) by @renovate[bot] - deps: update rust crate oxc_sourcemap to v8.1.2 (#10356) by @renovate[bot] - deps: update dependency vite-plus to v0.2.5 (#10329) by @renovate[bot] - docs: migrate Netlify redirects to Void config (#10282) by @tux-tn - deps: update dependency rust to v1.97.1 (#10317) by @renovate[bot] - runtime: remove unused `runtime/index.js` (#10302) by @IWANABETHATGUY ### ❤️ New Contributors * @dogledogle made their first contribution in [#10523](#10523) * @tbvjaos510 made their first contribution in [#10489](#10489) * @martijnwalraven made their first contribution in [#10440](#10440) * @shantanuraj made their first contribution in [#10438](#10438) * @Nic-Polumeyv made their first contribution in [#10450](#10450) * @hanayashiki made their first contribution in [#10451](#10451) * @unknownjedi made their first contribution in [#10426](#10426) * @vittorioexp made their first contribution in [#10382](#10382) * @tux-tn made their first contribution in [#10282](#10282) Co-authored-by: shulaoda <165626830+shulaoda@users.noreply.github.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
Two independent, cheap fixes to the strict-execution-order cross-chunk link pass (review items 3 and 4):
add_transitive_esm_init_depended_symbolsiterated anFxHashMapvia.values(), whose bucket order follows FxHash layout. FxHash is unseeded but hashes differently on 32-bit vs 64-bit, so that order — which flows into the chunk'sdepended_symbolsFxIndexSetand thence into imported-symbol rename order (the$1/$2suffixes) indeconflict_chunk_symbols— could diverge between native and wasm32/WASI builds. Now iterated sorted by the owningStmtInfoIdx, pinning one order everywhere. It is the single hash-ordered site three review passes converged on; every other hash-ordered effect is already sorted before use.module_is_in_live_chunkdid a linearchunk.modules.containsscan, called for every canonical referenced symbol of every included statement under strict — quadratic on large chunks. Replaced with an O(1)module_to_chunk+ liveness check.The O(1) rewrite is verified semantically equivalent:
add_module_to_chunksetsmodule_to_chunk[m]and pushesmontoc.modulestogether, and every site that later removes a module from a chunk'smoduleslist preserves the invariant (module_to_chunk[m] == Some(c) && c live ⟹ c.modules ∋ m) by pairing the removal with clearingmodule_to_chunk[m](unused-runtime sweep), reassigning it to the destination chunk viaadd_module_to_chunk(runtime relocation, runtime→target merge,apply_common_chunk_merges), or marking the emptied chunkRemoved. No site leavesmodule_to_chunkpointed at a still-live chunk that no longer contains the module, so no removed-module set is needed. The invariant is documented in the function's doc comment.Behavior / snapshot impact
None. Zero fixture snapshot changes. The determinism fix is invisible on native 64-bit (its value is native-vs-wasm parity, which the native suite cannot exercise); the O(1) change is a pure performance rewrite with identical results.
Validation
cargo test -p rolldown— 1868 passed; snapshot-stable (zero deltas). The only failures are 5 pre-existing environmental ones unrelated to this change (cjs_module_lexer_compat×3 andnpm_packages/util_deprecateneed an installedcjs-module-lexer;test262needs the test262 submodule).cargo fmt --all --check— clean.cargo clippy -p rolldown --all-targets -- -D warnings— clean.Follow-up to #10104; addresses the two "cheap pre-merge fixes" (items 3 and 4) from the review discussion: #10104 (comment)