SIL: Remove SILWitnessTable::AssociatedConformanceWitness::SubstType

slavapestov · slavapestov · commit ec82f6bf4dd3 · 2025-04-07T21:36:06.000-04:00
diff --git a/SwiftCompilerSources/Sources/Optimizer/Utilities/GenericSpecialization.swift b/SwiftCompilerSources/Sources/Optimizer/Utilities/GenericSpecialization.swift
@@ -144,7 +144,7 @@ func specializeWitnessTable(forConformance conformance: Conformance,
     case .associatedType(let requirement, let witness):
       let substType = witness.subst(with: conformance.specializedSubstitutions)
       return .associatedType(requirement: requirement, witness: substType)
-    case .associatedConformance(let requirement, let substType, let assocConf):
+    case .associatedConformance(let requirement, let assocConf):
       // FIXME: let concreteAssociateConf = assocConf.subst(with: conformance.specializedSubstitutions)
       let concreteAssociateConf = conformance.getAssociatedConformance(ofAssociatedType: requirement.rawType, to: assocConf.proto)
       if concreteAssociateConf.isSpecialized {
@@ -153,7 +153,6 @@ func specializeWitnessTable(forConformance conformance: Conformance,
                                context, notifyNewWitnessTable)
       }
       return .associatedConformance(requirement: requirement,
-                                    substType: substType.subst(with: conformance.specializedSubstitutions),
                                     witness: concreteAssociateConf)
     }
   }
diff --git a/SwiftCompilerSources/Sources/SIL/WitnessTable.swift b/SwiftCompilerSources/Sources/SIL/WitnessTable.swift
@@ -31,7 +31,7 @@ public struct WitnessTable : CustomStringConvertible, NoReflectionChildren {
     case associatedType(requirement: AssociatedTypeDecl, witness: CanonicalType)
 
     /// A witness table entry describing the witness for an associated type's protocol requirement.
-    case associatedConformance(requirement: CanonicalType, substType: CanonicalType, witness: Conformance)
+    case associatedConformance(requirement: CanonicalType, witness: Conformance)
 
     /// A witness table entry referencing the protocol conformance for a refined base protocol.
     case baseProtocol(requirement: ProtocolDecl, witness: Conformance)
@@ -48,7 +48,6 @@ public struct WitnessTable : CustomStringConvertible, NoReflectionChildren {
                                witness: CanonicalType(bridged: bridged.getAssociatedTypeWitness()))
       case .associatedConformance:
         self = .associatedConformance(requirement: CanonicalType(bridged: bridged.getAssociatedConformanceRequirement()),
-                                      substType: CanonicalType(bridged: bridged.getAssociatedConformanceSubstType()),
                                       witness: Conformance(bridged: bridged.getAssociatedConformanceWitness()))
       case .baseProtocol:
         self = .baseProtocol(requirement: bridged.getBaseProtocolRequirement().getAs(ProtocolDecl.self),
@@ -71,9 +70,8 @@ public struct WitnessTable : CustomStringConvertible, NoReflectionChildren {
                                                      OptionalBridgedFunction(obj: witness?.bridged.obj))
       case .associatedType(let requirement, let witness):
         return BridgedWitnessTableEntry.createAssociatedType(requirement.bridged, witness.bridged)
-      case .associatedConformance(let requirement, let substType, let witness):
+      case .associatedConformance(let requirement, let witness):
         return BridgedWitnessTableEntry.createAssociatedConformance(requirement.bridged,
-                                                                    substType.bridged,
                                                                     witness.bridged)
       case .baseProtocol(let requirement, let witness):
         return BridgedWitnessTableEntry.createBaseProtocol(requirement.bridged, witness.bridged)
diff --git a/include/swift/SIL/SILBridging.h b/include/swift/SIL/SILBridging.h
@@ -1062,7 +1062,6 @@ struct BridgedWitnessTableEntry {
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE BridgedDeclObj getAssociatedTypeRequirement() const;
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE BridgedCanType getAssociatedTypeWitness() const;
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE BridgedCanType getAssociatedConformanceRequirement() const;
-  SWIFT_IMPORT_UNSAFE BRIDGED_INLINE BridgedCanType getAssociatedConformanceSubstType() const;
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE BridgedConformance getAssociatedConformanceWitness() const;
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE BridgedDeclObj getBaseProtocolRequirement() const;
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE BridgedConformance getBaseProtocolWitness() const;
@@ -1077,7 +1076,6 @@ struct BridgedWitnessTableEntry {
                                                        BridgedCanType witness);
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE
   static BridgedWitnessTableEntry createAssociatedConformance(BridgedCanType requirement,
-                                                              BridgedCanType substType,
                                                               BridgedConformance witness);
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE
   static BridgedWitnessTableEntry createBaseProtocol(BridgedDeclObj requirement,
diff --git a/include/swift/SIL/SILBridgingImpl.h b/include/swift/SIL/SILBridgingImpl.h
@@ -1922,10 +1922,6 @@ BridgedCanType BridgedWitnessTableEntry::getAssociatedConformanceRequirement() c
   return unbridged().getAssociatedConformanceWitness().Requirement;
 }
 
-BridgedCanType BridgedWitnessTableEntry::getAssociatedConformanceSubstType() const {
-  return {unbridged().getAssociatedConformanceWitness().SubstType};
-}
-
 BridgedConformance BridgedWitnessTableEntry::getAssociatedConformanceWitness() const {
   return {unbridged().getAssociatedConformanceWitness().Witness};
 }
@@ -1957,11 +1953,9 @@ BridgedWitnessTableEntry BridgedWitnessTableEntry::createAssociatedType(BridgedD
 }
 
 BridgedWitnessTableEntry BridgedWitnessTableEntry::createAssociatedConformance(BridgedCanType requirement,
-                                                                               BridgedCanType substType,
                                                                                BridgedConformance witness) {
   return bridge(swift::SILWitnessTable::Entry(
     swift::SILWitnessTable::AssociatedConformanceWitness{requirement.unbridged(),
-                                                         substType.unbridged(),
                                                          witness.unbridged()}));
 }
 
diff --git a/include/swift/SIL/SILWitnessTable.h b/include/swift/SIL/SILWitnessTable.h
@@ -66,8 +66,6 @@ class SILWitnessTable : public llvm::ilist_node<SILWitnessTable>,
   struct AssociatedConformanceWitness {
     /// The subject type of the associated requirement.
     CanType Requirement;
-    /// FIXME: Temporary.
-    CanType SubstType;
     /// The ProtocolConformanceRef satisfying the requirement.
     ProtocolConformanceRef Witness;
   };
diff --git a/lib/SIL/IR/SILPrinter.cpp b/lib/SIL/IR/SILPrinter.cpp
@@ -4350,7 +4350,7 @@ void SILWitnessTable::Entry::print(llvm::raw_ostream &out, bool verbose,
       conformance.getConcrete()->printName(out, options);
     else {
       out << "dependent ";
-      assocProtoWitness.SubstType->print(out, options);
+      assocProtoWitness.Witness.getType()->print(out, options);
     }
     break;
   }
diff --git a/lib/SIL/Parser/ParseSIL.cpp b/lib/SIL/Parser/ParseSIL.cpp
@@ -8229,15 +8229,13 @@ static bool parseSILWitnessTableEntry(
         P.parseToken(tok::colon, diag::expected_sil_witness_colon))
       return true;
 
-    CanType substType;
     ProtocolConformanceRef conformance;
     if (P.Tok.getText() != "dependent") {
       auto concrete =
         witnessState.parseProtocolConformance();
       // Ignore invalid and abstract witness entries.
       if (concrete.isInvalid() || !concrete.isConcrete())
         return false;
-      substType = concrete.getConcrete()->getType()->getCanonicalType();
       conformance = concrete;
     } else {
       P.consumeToken();
@@ -8261,15 +8259,13 @@ static bool parseSILWitnessTableEntry(
       if (Ty->hasError())
         return true;
 
-      substType = Ty->getCanonicalType();
       conformance = ProtocolConformanceRef::forAbstract(
           Ty->getCanonicalType(), proto);
     }
 
     if (EntryKeyword.str() == "associated_conformance")
       witnessEntries.push_back(
           SILWitnessTable::AssociatedConformanceWitness{assocOrSubject,
-                                                        substType,
                                                         conformance});
     else
       conditionalConformances.push_back(conformance);
diff --git a/lib/SILGen/SILGenType.cpp b/lib/SILGen/SILGenType.cpp
@@ -692,12 +692,8 @@ class SILGenConformance : public SILGenWitnessTable<SILGenConformance> {
       Conformance->getAssociatedConformance(req.getAssociation(),
                                             req.getAssociatedRequirement());
     SGM.useConformance(assocConformance);
-
-    auto substType = (assocConformance
-                      ? assocConformance.getType()
-                      : ErrorType::get(SGM.getASTContext()))->getCanonicalType();
     Entries.push_back(SILWitnessTable::AssociatedConformanceWitness{
-        req.getAssociation(), substType, assocConformance});
+        req.getAssociation(), assocConformance});
   }
 
   void addConditionalRequirements() {
@@ -1125,7 +1121,7 @@ class SILGenDefaultWitnessTable
       return addMissingDefault();
 
     auto entry = SILWitnessTable::AssociatedConformanceWitness{
-        req.getAssociation(), req.getAssociation(), witness};
+        req.getAssociation(), witness};
     DefaultWitnesses.push_back(entry);
   }
 };
diff --git a/lib/Serialization/DeserializeSIL.cpp b/lib/Serialization/DeserializeSIL.cpp
@@ -4488,15 +4488,12 @@ void SILDeserializer::readWitnessTableEntries(
       });
     } else if (kind == SIL_WITNESS_ASSOC_PROTOCOL) {
       TypeID origTypeId;
-      DeclID substTypeId;
       ProtocolConformanceID conformanceId;
-      WitnessAssocProtocolLayout::readRecord(scratch, origTypeId, substTypeId,
-                                             conformanceId);
+      WitnessAssocProtocolLayout::readRecord(scratch, origTypeId, conformanceId);
       CanType origType = MF->getType(origTypeId)->getCanonicalType();
-      CanType substType = MF->getType(substTypeId)->getCanonicalType();
       auto conformance = MF->getConformance(conformanceId);
       witnessEntries.push_back(SILWitnessTable::AssociatedConformanceWitness{
-        origType, substType, conformance
+        origType, conformance
       });
     } else if (kind == SIL_WITNESS_ASSOC_ENTRY) {
       DeclID assocId;
diff --git a/lib/Serialization/ModuleFormat.h b/lib/Serialization/ModuleFormat.h
@@ -58,7 +58,7 @@ const uint16_t SWIFTMODULE_VERSION_MAJOR = 0;
 /// describe what change you made. The content of this comment isn't important;
 /// it just ensures a conflict if two people change the module format.
 /// Don't worry about adhering to the 80-column limit for this line.
-const uint16_t SWIFTMODULE_VERSION_MINOR = 936; // Remove SILWitnessTable::ConditionalConformance
+const uint16_t SWIFTMODULE_VERSION_MINOR = 937; // Simplify SILWitnessTable
 
 /// A standard hash seed used for all string hashes in a serialized module.
 ///
diff --git a/lib/Serialization/SILFormat.h b/lib/Serialization/SILFormat.h
@@ -249,7 +249,6 @@ namespace sil_block {
   using WitnessAssocProtocolLayout = BCRecordLayout<
     SIL_WITNESS_ASSOC_PROTOCOL,
     TypeIDField, // ID of requirement subject type
-    TypeIDField, // ID of substituted subject type
     ProtocolConformanceIDField
   >;
 
diff --git a/lib/Serialization/SerializeSIL.cpp b/lib/Serialization/SerializeSIL.cpp
@@ -3401,13 +3401,12 @@ void SILSerializer::writeSILWitnessTableEntry(
     auto &assoc = entry.getAssociatedConformanceWitness();
 
     auto requirementID = S.addTypeRef(assoc.Requirement);
-    auto substTypeID = S.addTypeRef(assoc.SubstType);
     auto conformanceID = S.addConformanceRef(assoc.Witness);
 
     WitnessAssocProtocolLayout::emitRecord(
       Out, ScratchRecord,
       SILAbbrCodes[WitnessAssocProtocolLayout::Code],
-      requirementID, substTypeID, conformanceID);
+      requirementID, conformanceID);
     return;
   }
 

Original file line number	Diff line number	Diff line change
`@@ -144,7 +144,7 @@ func specializeWitnessTable(forConformance conformance: Conformance,`
`144`	`144`	`case .associatedType(let requirement, let witness):`
`145`	`145`	`let substType = witness.subst(with: conformance.specializedSubstitutions)`
`146`	`146`	`return .associatedType(requirement: requirement, witness: substType)`
`147`		`- case .associatedConformance(let requirement, let substType, let assocConf):`
	`147`	`+ case .associatedConformance(let requirement, let assocConf):`
`148`	`148`	`// FIXME: let concreteAssociateConf = assocConf.subst(with: conformance.specializedSubstitutions)`
`149`	`149`	`let concreteAssociateConf = conformance.getAssociatedConformance(ofAssociatedType: requirement.rawType, to: assocConf.proto)`
`150`	`150`	`if concreteAssociateConf.isSpecialized {`
`@@ -153,7 +153,6 @@ func specializeWitnessTable(forConformance conformance: Conformance,`
`153`	`153`	`context, notifyNewWitnessTable)`
`154`	`154`	`}`
`155`	`155`	`return .associatedConformance(requirement: requirement,`
`156`		`- substType: substType.subst(with: conformance.specializedSubstitutions),`
`157`	`156`	`witness: concreteAssociateConf)`
`158`	`157`	`}`
`159`	`158`	`}`
Original file line number	Diff line number	Diff line change
`@@ -1922,10 +1922,6 @@ BridgedCanType BridgedWitnessTableEntry::getAssociatedConformanceRequirement() c`
`1922`	`1922`	`return unbridged().getAssociatedConformanceWitness().Requirement;`
`1923`	`1923`	`}`
`1924`	`1924`
`1925`		`-BridgedCanType BridgedWitnessTableEntry::getAssociatedConformanceSubstType() const {`
`1926`		`- return {unbridged().getAssociatedConformanceWitness().SubstType};`
`1927`		`-}`
`1928`		`-`
`1929`	`1925`	`BridgedConformance BridgedWitnessTableEntry::getAssociatedConformanceWitness() const {`
`1930`	`1926`	`return {unbridged().getAssociatedConformanceWitness().Witness};`
`1931`	`1927`	`}`
`@@ -1957,11 +1953,9 @@ BridgedWitnessTableEntry BridgedWitnessTableEntry::createAssociatedType(BridgedD`
`1957`	`1953`	`}`
`1958`	`1954`
`1959`	`1955`	`BridgedWitnessTableEntry BridgedWitnessTableEntry::createAssociatedConformance(BridgedCanType requirement,`
`1960`		`- BridgedCanType substType,`
`1961`	`1956`	`BridgedConformance witness) {`
`1962`	`1957`	`return bridge(swift::SILWitnessTable::Entry(`
`1963`	`1958`	`swift::SILWitnessTable::AssociatedConformanceWitness{requirement.unbridged(),`
`1964`		`- substType.unbridged(),`
`1965`	`1959`	`witness.unbridged()}));`
`1966`	`1960`	`}`
`1967`	`1961`
Original file line number	Diff line number	Diff line change
`@@ -4350,7 +4350,7 @@ void SILWitnessTable::Entry::print(llvm::raw_ostream &out, bool verbose,`
`4350`	`4350`	`conformance.getConcrete()->printName(out, options);`
`4351`	`4351`	`else {`
`4352`	`4352`	`out << "dependent ";`
`4353`		`- assocProtoWitness.SubstType->print(out, options);`
	`4353`	`+ assocProtoWitness.Witness.getType()->print(out, options);`
`4354`	`4354`	`}`
`4355`	`4355`	`break;`
`4356`	`4356`	`}`