Only materialize reachable code for back passes - #3039
Draft
plajjan wants to merge 9 commits into
Draft
Conversation
The synchronous output path still checked generation eligibility after announcing that a write had started. An implementation refresh could also commit its rows before forcing the restored module values used by the following back pass. Decide synchronous-write eligibility once, then always finish the announced action and report its timing. Force restored module values before the refreshed transaction commits, so front completion remains a single reliable boundary for every later row reader.
plajjan
changed the title
added 7 commits
July 25, 2026 09:17
Split inferred modules into validated top, member, constructor-fragment, and compact-header rows that preserve source order and lowering semantics. Expose the type checker's constructor analysis as the canonical boundary for attribute initialization, and share actor-state classification with Deactorizer. This lets later projections restore only the declarations and initialization fragments they need.
Derive witness-forwarding plans before code generation and walk inferred modules with their type environments to record exact top-level, member, constructor, provider, shape, and reflection obligations. Store typed rows, reachability, hash inputs, and generation identity in one interface snapshot. Resolve aliases while classifying receivers, record Normalizer's truth conversions, and retain inherited property declarations needed to keep whole and selective layouts identical. Missing or impossible typed targets remain compiler errors; selection never widens to wildcard interest. Bump the interface version so caches written without these rows are rebuilt.
Close typed reachability with an exact-key, order-independent worklist, including inherited providers, constructors, witness dictionaries, reflection, fields, initializer fragments, and generated slots. Restore only selected rows from one interface snapshot and assemble a coherent module and environment for the existing back pipeline. Missing, ambiguous or generation-shifted rows are errors rather than reasons to widen the projection.
Plan whole and projected provider work separately, run projections against their captured interface generation, and serialize generated output by destination across the CLI, language server, tests, and benchmarks. Keep one generation-bound read session per projection and query only the public names, headers, bodies, reachability rows, and opaque hashes demanded by its worklist. Install declaration-only bindings in projected environments and preserve empty projected imports as module initialization dependencies. Directly requested rootless modules stop after interface work unless a declared library or diagnostic output requires a back pass. They do not seed provider work; executable roots still drive exact selection.
Run reachability, row reconstruction, worklist closure, projection, and witness-forwarding checks through one selective library test executable. Compile and run end-to-end projects across deferred scheduling, generated C, incremental invalidation, inheritance, native providers, output locking, and consumer-specific provider output. Cover aliases, optional truth conversion, inherited property layouts, module initialization, declaration-only ABI types, and rootless module requests. The fixtures include the important cases carried over from dce2.
The deferred compiler now separates front-pass persistence, typed reachability closure, selective materialization, and generation-bound code generation. The old cache documentation described monolithic interfaces and whole-module implementation hashes. Describe exact interface rows and keys, module-owned hash components, consumer-specific projections, constructor fragments, opaque and native boundaries, snapshot validation, output locks, and the codegen hash. Missing exact rows remain errors and never widen to wildcard interest.
Selective compilation computes both a closed project selection and per-module dependency facts, but neither was available for inspection. Let acton sig --reachability with no target print the project selection without running back jobs or mixing the report with build progress. Accept "." as an explicit project target. Module and exact-name targets inspect cached TYDB facts. That inspection may enumerate a requested module; normal selection continues to use exact-key reads. Render both views deterministically for human review and regression testing.
The lock test assumed a child compiler reached the project lock within 500 ms. Compiler startup can take longer on macOS, letting the parent release the lock before the child attempts acquisition. Read the child's line-buffered output until it reports waiting for the lock, then release it and require the build to succeed. This proves the failed immediate acquisition without depending on startup timing.
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
1 participant
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.
Front passes run on 100% of a module. This changes so that for back passes, we only load and process names that are reachable.
Reachability facts are stored as exact TYDB rows and selected interfaces are reconstructed on demand. Rootless modules stop after front-pass persistence, while executable builds generate consumer-specific provider projections.
The project selection can be inspected with acton sig --reachability. Module and exact-name targets show the cached reachability facts stored in a TYDB.