More SubstitutionList => SubstitutionMap cleanups #7969
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ASTContext::getSpecializedConformance() already copies the substitutions, so remove some AllocateCopy() calls. Also, add a new overload taking a SubstitutionMap instead. This allows removing some gatherAllSubstitutions() calls, which have an allocation inside them. Finally, remove the now-unused ModuleDecl parameter from ProtocolConformance::subst() and make it public.
Extract this from Substitution::subst(), which is going away.
This will replace Substitution::subst().
…Cloner This also fixes a latent bug; we were substituting opened existentials inside the replacement type of a Substitution, but not inside the conformances.
I want to get rid of Substitution entirely, and now we have the right abstractions to do everything with SubstitutionMap.
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@swift-ci Please test |
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@swiftix Please take a look. |
| @@ -351,6 +349,11 @@ bool SILPerformanceInliner::isProfitableToInline(FullApplySite AI, | |||
| int BaseBenefit = RemovedCallBenefit; | |||
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| SubstitutionMap CalleeSubstMap; | |||
| if (IsGeneric) { | |||
| CalleeSubstMap = Callee->getGenericEnvironment() | |||
| ->getSubstitutionMap(AI.getSubstitutions()); | |||
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@slavapestov please construct this map only on demand. There is no need to always create it.
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Once the new representation is done, going from a list to a map will be O(1), and going from a map to a list will just be a memcpy :-)
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I like that we can now perform substitutions on the whole SubstitutionMap and on conformances. This is very useful. |
| auto newConformance = | ||
| conformance.subst(ty, | ||
| [&](SubstitutableType *t) -> Type { | ||
| if (t->isOpenedExistential()) { |
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Use llvm's early return style here. if (!t-> isOpenedExistential()) return t; This will reduce the indentation.
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Build failed |
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Looks like we hit a non deterministic crasher. I'll make a separate PR to disable it. |
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@swift-ci Please smoke test macOS |
The goal here is to eliminate a few calls to TypeBase::gatherAllSubstitutions() and entirely kill off Substitution::subst(), dealing with the fallout along the way.
The main improvement is that we now have public APIs to substitute conformances, as well as a SubstitutionMap::subst() that substitutes all replacement types. Also, some unnecessary allocations in the permanent arena are now eliminated.