RequirementMachine: Preliminary support for minimizing layout, superclass and concrete type requirements

Author: slavapestov

lib/AST/RequirementMachine/RequirementMachineRequests.cpp

@@ -50,12 +50,13 @@ RequirementMachine::buildRequirementSignature(ArrayRef<unsigned> rules,
   llvm::SmallDenseMap<TypeBase *, llvm::SmallVector<Type, 2>> sameTypeReqs;
 
   auto genericParams = proto->getGenericSignature().getGenericParams();
+  const auto &protos = System.getProtocols();
 
   // Convert a rewrite rule into a requirement.
   auto createRequirementFromRule = [&](const Rule &rule) {
     if (auto prop = rule.isPropertyRule()) {
       auto subjectType = Context.getTypeForTerm(rule.getRHS(), genericParams,
-                                                System.getProtocols());
+                                                protos);
 
       switch (prop->getKind()) {
       case Symbol::Kind::Protocol:
@@ -65,9 +66,29 @@ RequirementMachine::buildRequirementSignature(ArrayRef<unsigned> rules,
         return;
 
       case Symbol::Kind::Layout:
-      case Symbol::Kind::ConcreteType:
+        reqs.emplace_back(RequirementKind::Layout,
+                          subjectType,
+                          prop->getLayoutConstraint());
+        return;
+
       case Symbol::Kind::Superclass:
-        // FIXME
+        reqs.emplace_back(RequirementKind::Superclass,
+                          subjectType,
+                          Context.getTypeFromSubstitutionSchema(
+                              prop->getSuperclass(),
+                              prop->getSubstitutions(),
+                              genericParams, MutableTerm(),
+                              protos));
+        return;
+
+      case Symbol::Kind::ConcreteType:
+        reqs.emplace_back(RequirementKind::SameType,
+                          subjectType,
+                          Context.getTypeFromSubstitutionSchema(
+                              prop->getConcreteType(),
+                              prop->getSubstitutions(),
+                              genericParams, MutableTerm(),
+                              protos));
         return;
 
       case Symbol::Kind::Name:
@@ -79,9 +100,9 @@ RequirementMachine::buildRequirementSignature(ArrayRef<unsigned> rules,
       llvm_unreachable("Invalid symbol kind");
     } else if (rule.getLHS().back().getKind() != Symbol::Kind::Protocol) {
       auto constraintType = Context.getTypeForTerm(rule.getLHS(), genericParams,
-                                                   System.getProtocols());
+                                                   protos);
       auto subjectType = Context.getTypeForTerm(rule.getRHS(), genericParams,
-                                                System.getProtocols());
+                                                protos);
 
       sameTypeReqs[subjectType.getPointer()].push_back(constraintType);
     }

test/Generics/sr14580.swift

@@ -1,5 +1,5 @@
-// RUN: %target-typecheck-verify-swift
-// RUN: %target-swift-frontend -typecheck -debug-generic-signatures %s 2>&1 | %FileCheck %s
+// RUN: %target-typecheck-verify-swift -requirement-machine-protocol-signatures=on
+// RUN: %target-swift-frontend -typecheck -debug-generic-signatures -requirement-machine-protocol-signatures=on %s 2>&1 | %FileCheck %s
 
 public protocol ScalarProtocol: ScalarMultiplicative where Self == Scalar {
 }
@@ -13,10 +13,8 @@ public protocol MapReduceArithmetic: ScalarMultiplicative, Collection where Elem
 public protocol Tensor: MapReduceArithmetic where Element == Scalar {
 }
 
-// FIXME: The same-type requirement canonicalization still produces bugus results here, but
-// at least we don't crash.
-
-// CHECK-LABEL: Requirement signature: <Self where Self : Tensor, Self == Self.Float16Components.Model, Self.Element == Double, Self.Float16Components : ColorComponents, Self.Float32Components : ColorComponents, Self.Float16Components.Element == Double, Self.Float16Components.Model == Self.Float32Components.Model, Self.Float32Components.Element == Double, Self.Float32Components.Indices == Self.Float32Components.Indices.SubSequence, Self.Float32Components.SubSequence == Self.Float32Components.SubSequence.SubSequence, Self.Float32Components.Indices.Indices == Self.Float32Components.Indices.Indices.SubSequence, Self.Float32Components.SubSequence.Indices == Self.Float32Components.SubSequence.Indices.SubSequence, Self.Float32Components.SubSequence.Indices.Indices == Self.Float32Components.SubSequence.Indices.Indices.SubSequence>
+// CHECK-LABEL: sr14580.(file).ColorModel@
+// CHECK-LABEL: Requirement signature: <Self where Self : Tensor, Self == Self.Float16Components.Model, Self.Element == Double, Self.Float16Components : ColorComponents, Self.Float32Components : ColorComponents, Self.Float16Components.Element == Double, Self.Float16Components.Model == Self.Float32Components.Model, Self.Float32Components.Element == Double>
 public protocol ColorModel: Tensor where Scalar == Double {
   associatedtype Float16Components: ColorComponents where Float16Components.Model == Self, Float16Components.Scalar == Double
   associatedtype Float32Components: ColorComponents where Float32Components.Model == Self, Float32Components.Scalar == Double