Merge pull request swiftlang#39864 from slavapestov/rqm-refactor-protocol-linear-order

RequirementMachine: Protocol reduction order refactoring

Author: slavapestov

lib/AST/CMakeLists.txt

@@ -79,7 +79,6 @@ add_swift_host_library(swiftAST STATIC
   RequirementMachine/GenericSignatureQueries.cpp
   RequirementMachine/PropertyMap.cpp
   RequirementMachine/PropertyUnification.cpp
-  RequirementMachine/ProtocolGraph.cpp
   RequirementMachine/RequirementMachine.cpp
   RequirementMachine/RequirementMachineRequests.cpp
   RequirementMachine/RewriteContext.cpp

lib/AST/RequirementMachine/GenericSignatureQueries.cpp

@@ -37,22 +37,20 @@ RequirementMachine::getLocalRequirements(
   System.simplify(term);
   verify(term);
 
-  auto &protos = System.getProtocols();
-
   GenericSignature::LocalRequirements result;
-  result.anchor = Context.getTypeForTerm(term, genericParams, protos);
+  result.anchor = Context.getTypeForTerm(term, genericParams);
 
   auto *props = Map.lookUpProperties(term);
   if (!props)
     return result;
 
   if (props->isConcreteType()) {
-    result.concreteType = props->getConcreteType({}, term, protos, Context);
+    result.concreteType = props->getConcreteType({}, term, Context);
     return result;
   }
 
   if (props->hasSuperclassBound()) {
-    result.superclass = props->getSuperclassBound({}, term, protos, Context);
+    result.superclass = props->getSuperclassBound({}, term, Context);
   }
 
   for (const auto *proto : props->getConformsToExcludingSuperclassConformances())
@@ -154,8 +152,7 @@ getSuperclassBound(Type depType,
   if (!props->hasSuperclassBound())
     return Type();
 
-  auto &protos = System.getProtocols();
-  return props->getSuperclassBound(genericParams, term, protos, Context);
+  return props->getSuperclassBound(genericParams, term, Context);
 }
 
 bool RequirementMachine::isConcreteType(Type depType) const {
@@ -186,8 +183,7 @@ getConcreteType(Type depType,
   if (!props->isConcreteType())
     return Type();
 
-  auto &protos = System.getProtocols();
-  return props->getConcreteType(genericParams, term, protos, Context);
+  return props->getConcreteType(genericParams, term, Context);
 }
 
 bool RequirementMachine::areSameTypeParameterInContext(Type depType1,
@@ -217,9 +213,6 @@ RequirementMachine::getLongestValidPrefix(const MutableTerm &term) const {
     case Symbol::Kind::Protocol:
       assert(prefix.empty() &&
              "Protocol symbol can only appear at the start of a type term");
-      if (!System.getProtocols().isKnownProtocol(symbol.getProtocol()))
-        return prefix;
-
       break;
 
     case Symbol::Kind::GenericParam:
@@ -235,9 +228,6 @@ RequirementMachine::getLongestValidPrefix(const MutableTerm &term) const {
       auto conformsTo = props->getConformsTo();
 
       for (const auto *proto : symbol.getProtocols()) {
-        if (!System.getProtocols().isKnownProtocol(proto))
-          return prefix;
-
         // T.[P:A] is valid iff T conforms to P.
         if (std::find(conformsTo.begin(), conformsTo.end(), proto)
               == conformsTo.end())
@@ -268,8 +258,6 @@ RequirementMachine::getLongestValidPrefix(const MutableTerm &term) const {
 /// not considered canonical, since they can be replaced with their
 /// concrete type).
 bool RequirementMachine::isCanonicalTypeInContext(Type type) const {
-  auto &protos = System.getProtocols();
-
   // Look for non-canonical type parameters.
   return !type.findIf([&](Type component) -> bool {
     if (!component->isTypeParameter())
@@ -288,7 +276,7 @@ bool RequirementMachine::isCanonicalTypeInContext(Type type) const {
     if (props->isConcreteType())
       return true;
 
-    auto anchor = Context.getTypeForTerm(term, {}, protos);
+    auto anchor = Context.getTypeForTerm(term, {});
     return CanType(anchor) != CanType(component);
   });
 }
@@ -304,7 +292,6 @@ bool RequirementMachine::isCanonicalTypeInContext(Type type) const {
 Type RequirementMachine::getCanonicalTypeInContext(
     Type type,
     TypeArrayView<GenericTypeParamType> genericParams) const {
-  const auto &protos = System.getProtocols();
 
   return type.transformRec([&](Type t) -> Optional<Type> {
     if (!t->isTypeParameter())
@@ -353,8 +340,7 @@ Type RequirementMachine::getCanonicalTypeInContext(
       if (props) {
         if (props->isConcreteType()) {
           auto concreteType = props->getConcreteType(genericParams,
-                                                     prefix, protos,
-                                                     Context);
+                                                     prefix, Context);
           if (!concreteType->hasTypeParameter())
             return concreteType;
 
@@ -369,8 +355,7 @@ Type RequirementMachine::getCanonicalTypeInContext(
         if (props->hasSuperclassBound() &&
             prefix.size() != term.size()) {
           auto superclass = props->getSuperclassBound(genericParams,
-                                                      prefix, protos,
-                                                      Context);
+                                                      prefix, Context);
           if (!superclass->hasTypeParameter())
             return superclass;
 
@@ -379,7 +364,7 @@ Type RequirementMachine::getCanonicalTypeInContext(
         }
       }
 
-      return Context.getTypeForTerm(prefix, genericParams, protos);
+      return Context.getTypeForTerm(prefix, genericParams);
     }();
 
     // If T is already valid, the longest valid prefix U of T is T itself, and
@@ -404,8 +389,7 @@ Type RequirementMachine::getCanonicalTypeInContext(
 
     // Compute the type of the unresolved suffix term V, rooted in the
     // generic parameter τ_0_0.
-    auto origType = Context.getRelativeTypeForTerm(
-        term, prefix, System.getProtocols());
+    auto origType = Context.getRelativeTypeForTerm(term, prefix);
 
     // Substitute τ_0_0 in the above relative type with the concrete type
     // for U.

lib/AST/RequirementMachine/HomotopyReduction.cpp

@@ -676,7 +676,7 @@ findRuleToDelete(bool firstPass,
       const auto &otherRule = getRule(*found);
 
       // Prefer to delete "less canonical" rules.
-      if (rule.compare(otherRule, Protos) > 0)
+      if (rule.compare(otherRule, Context) > 0)
         found = ruleID;
     }
 

lib/AST/RequirementMachine/PropertyMap.cpp

@@ -152,13 +152,11 @@ PropertyBag::getPrefixAfterStrippingKey(const MutableTerm &lookupTerm) const {
 Type PropertyBag::getSuperclassBound(
     TypeArrayView<GenericTypeParamType> genericParams,
     const MutableTerm &lookupTerm,
-    const ProtocolGraph &protos,
     RewriteContext &ctx) const {
   MutableTerm prefix = getPrefixAfterStrippingKey(lookupTerm);
   return ctx.getTypeFromSubstitutionSchema(Superclass->getSuperclass(),
                                            Superclass->getSubstitutions(),
-                                           genericParams, prefix,
-                                           protos);
+                                           genericParams, prefix);
 }
 
 /// Get the concrete type of the term represented by this property bag.
@@ -173,13 +171,11 @@ Type PropertyBag::getSuperclassBound(
 Type PropertyBag::getConcreteType(
     TypeArrayView<GenericTypeParamType> genericParams,
     const MutableTerm &lookupTerm,
-    const ProtocolGraph &protos,
     RewriteContext &ctx) const {
   MutableTerm prefix = getPrefixAfterStrippingKey(lookupTerm);
   return ctx.getTypeFromSubstitutionSchema(ConcreteType->getConcreteType(),
                                            ConcreteType->getSubstitutions(),
-                                           genericParams, prefix,
-                                           protos);
+                                           genericParams, prefix);
 }
 
 void PropertyBag::copyPropertiesFrom(const PropertyBag *next,

lib/AST/RequirementMachine/PropertyMap.h

@@ -26,7 +26,6 @@
 #include <vector>
 
 #include "Debug.h"
-#include "ProtocolGraph.h"
 #include "RewriteContext.h"
 #include "RewriteSystem.h"
 
@@ -102,7 +101,6 @@ class PropertyBag {
   Type getSuperclassBound(
       TypeArrayView<GenericTypeParamType> genericParams,
       const MutableTerm &lookupTerm,
-      const ProtocolGraph &protos,
       RewriteContext &ctx) const;
 
   bool isConcreteType() const {
@@ -116,7 +114,6 @@ class PropertyBag {
   Type getConcreteType(
       TypeArrayView<GenericTypeParamType> genericParams,
       const MutableTerm &lookupTerm,
-      const ProtocolGraph &protos,
       RewriteContext &ctx) const;
 
   LayoutConstraint getLayoutConstraint() const {
@@ -146,7 +143,6 @@ class PropertyMap {
   using ConcreteTypeInDomain = std::pair<CanType, ArrayRef<const ProtocolDecl *>>;
   llvm::DenseMap<ConcreteTypeInDomain, Term> ConcreteTypeInDomainMap;
 
-  const ProtocolGraph &Protos;
   DebugOptions Debug;
 
   PropertyBag *getOrCreateProperties(Term key);
@@ -159,8 +155,7 @@ class PropertyMap {
 public:
   explicit PropertyMap(RewriteSystem &system)
       : Context(system.getRewriteContext()),
-        System(system),
-        Protos(system.getProtocols()) {
+        System(system) {
     Debug = Context.getDebugOptions();
   }
 

lib/AST/RequirementMachine/PropertyUnification.cpp

@@ -501,7 +501,7 @@ void PropertyMap::concretizeNestedTypesFromConcreteParent(
     // PropertyBag::getConformsToExcludingSuperclassConformances().
     conformances.push_back(concrete);
 
-    auto assocTypes = Protos.getProtocolInfo(proto).AssociatedTypes;
+    auto assocTypes = proto->getAssociatedTypeMembers();
     if (assocTypes.empty())
       continue;
 
@@ -543,7 +543,7 @@ void PropertyMap::concretizeNestedTypesFromConcreteParent(
           auto term = Context.getRelativeTermForType(t->getCanonicalType(),
                                                      substitutions);
           System.simplify(term);
-          return Context.getTypeForTerm(term, { }, Protos);
+          return Context.getTypeForTerm(term, { });
         }));
       };