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# Conflicts: # hkmc2DiffTests/src/test/scala/hkmc2/MLsDiffMaker.scala
…into hkmc2-deforest-new-new
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| // pre-process: assign each node an id | ||
| val edgesSet = edges.toSet | ||
| val nodesUniq = (edgesSet.flatMap { case (a, b) => Set(a, b) } ++ nodes.toSet).toList | ||
| val nodesUniq = { |
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I think this file is part of the core subproject, which uses Scala 2.
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Pull request overview
This PR adds a deforestation optimization pass to the hkmc2 compiler. Deforestation is an optimization that eliminates intermediate data structures by fusing producers (constructors) with consumers (pattern matches/selections). The PR supersedes PR #335.
Changes:
- Adds a complete deforestation pipeline: pre-analysis, constraint collection, constraint solving, and rewriting phases
- Integrates the deforestation pass into the lowering pipeline, controlled by a
:deforestcommand - Fixes determinism in the SCC partitioning algorithm and adds supporting infrastructure changes
Reviewed changes
Copilot reviewed 27 out of 27 changed files in this pull request and generated no comments.
Show a summary per file
| File | Description |
|---|---|
hkmc2/shared/src/main/scala/hkmc2/Config.scala |
Adds Deforest config case class and deforest field to Config |
hkmc2DiffTests/src/test/scala/hkmc2/MLsDiffMaker.scala |
Adds :deforest command for test files |
hkmc2/shared/src/main/scala/hkmc2/Uid.scala |
Adds Result and StratVar UID handlers for deforestation |
hkmc2/shared/src/main/scala/hkmc2/codegen/Block.scala |
Sets tsym on BlockMemberSymbol in FunDefn.withFreshSymbol |
hkmc2/shared/src/main/scala/hkmc2/codegen/LambdaRewriter.scala |
Refactors to use FunDefn.withFreshSymbol |
hkmc2/shared/src/main/scala/utils/TraceLogger.scala |
Widens emitDbg visibility to protected[hkmc2] |
core/shared/main/scala/utils/algorithms.scala |
Fixes nondeterminism in SCC by using LinkedHashSet |
hkmc2/shared/src/main/scala/hkmc2/codegen/Lowering.scala |
Integrates deforestation pass into lowering pipeline |
hkmc2/shared/src/main/scala/hkmc2/codegen/deforest/Deforest.scala |
Core types, extractors, and entry point for deforestation |
hkmc2/shared/src/main/scala/hkmc2/codegen/deforest/Analyze.scala |
Pre-analysis, constraint collection, and constraint solving |
hkmc2/shared/src/main/scala/hkmc2/codegen/deforest/Rewrite.scala |
Rewriting pass that applies deforestation transformations |
hkmc2/shared/src/test/mlscript/deforest/*.mls |
Comprehensive test suite for deforestation (12 test files) |
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Supersedes and closes #335