SIL: Remove SILWitnessTable::AssociatedConformanceWitness::SubstType

Author: slavapestov

SwiftCompilerSources/Sources/SIL/WitnessTable.swift

@@ -71,9 +71,8 @@ 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)

include/swift/SIL/SILBridging.h

@@ -1076,7 +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,

include/swift/SIL/SILBridgingImpl.h

@@ -1918,8 +1918,9 @@ BridgedCanType BridgedWitnessTableEntry::getAssociatedConformanceRequirement() c
   return unbridged().getAssociatedConformanceWitness().Requirement;
 }
 
+// FIXME: This is now redundant
 BridgedCanType BridgedWitnessTableEntry::getAssociatedConformanceSubstType() const {
-  return {unbridged().getAssociatedConformanceWitness().SubstType};
+  return {unbridged().getAssociatedConformanceWitness().Witness.getType()->getCanonicalType()};
 }
 
 BridgedConformance BridgedWitnessTableEntry::getAssociatedConformanceWitness() const {
@@ -1953,11 +1954,9 @@ 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()}));
 }
 

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;
   };

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;
   }

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);

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);
   }
 };

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;

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.
 ///

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
   >;
 

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;
   }