fix: move structProjCases pass before extendJoinPointContext #8752
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algebraic-dev
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Jun 18, 2025
…ver#8752) This PR fixes an issue where the `extendJoinPointContext` pass can lift join points containing projections to the top level, as siblings of `cases` constructs matching on other projections of the same base value. This prevents the `structProjCases` pass from projecting both at once, extending the lifetime of the parent value and breaking linearity at runtime. This would theoretically be possible to fix in `structProjCases`, but it would require some better infrastructure for handling join points. It's also likely that the IR passes dealing with reference counting would have similar bugs that pessimize the code. For this reason, the simplest thing is to just perform the `structProjCases` pass earlier, which prevents `extendJoinPointContext` from lifting these join points.
wkrozowski
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Jun 24, 2025
…ver#8752) This PR fixes an issue where the `extendJoinPointContext` pass can lift join points containing projections to the top level, as siblings of `cases` constructs matching on other projections of the same base value. This prevents the `structProjCases` pass from projecting both at once, extending the lifetime of the parent value and breaking linearity at runtime. This would theoretically be possible to fix in `structProjCases`, but it would require some better infrastructure for handling join points. It's also likely that the IR passes dealing with reference counting would have similar bugs that pessimize the code. For this reason, the simplest thing is to just perform the `structProjCases` pass earlier, which prevents `extendJoinPointContext` from lifting these join points.
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This PR fixes an issue where the
extendJoinPointContextpass can lift join points containing projections to the top level, as siblings ofcasesconstructs matching on other projections of the same base value. This prevents thestructProjCasespass from projecting both at once, extending the lifetime of the parent value and breaking linearity at runtime.This would theoretically be possible to fix in
structProjCases, but it would require some better infrastructure for handling join points. It's also likely that the IR passes dealing with reference counting would have similar bugs that pessimize the code. For this reason, the simplest thing is to just perform thestructProjCasespass earlier, which preventsextendJoinPointContextfrom lifting these join points.