[ConstraintSystem] Add a new locator element - type for body of a closure

Author: xedin

lib/Sema/ConstraintLocator.cpp

@@ -67,7 +67,8 @@ void ConstraintLocator::Profile(llvm::FoldingSetNodeID &id, Expr *anchor,
     case TypeParameterRequirement:
     case ContextualType:
     case SynthesizedArgument:
-    case TernaryBranch: {
+    case TernaryBranch:
+    case ClosureBody: {
       auto numValues = numNumericValuesInPathElement(elt.getKind());
       for (unsigned i = 0; i < numValues; ++i)
         id.AddInteger(elt.getValue(i));
@@ -87,6 +88,7 @@ unsigned LocatorPathElt::getNewSummaryFlags() const {
   case ConstraintLocator::ApplyFunction:
   case ConstraintLocator::SequenceElementType:
   case ConstraintLocator::ClosureResult:
+  case ConstraintLocator::ClosureBody:
   case ConstraintLocator::ConstructorMember:
   case ConstraintLocator::InstanceType:
   case ConstraintLocator::AutoclosureResult:
@@ -327,6 +329,10 @@ void ConstraintLocator::dump(SourceManager *sm, raw_ostream &out) const {
       out << "closure result";
       break;
 
+    case ClosureBody:
+      out << "type of a closure body";
+      break;
+
     case ConstructorMember:
       out << "constructor member";
       break;

lib/Sema/ConstraintLocator.h

@@ -71,6 +71,7 @@ class ConstraintLocator : public llvm::FoldingSetNode {
     case PatternMatch:
       return 0;
 
+    case ClosureBody:
     case ContextualType:
     case OpenedGeneric:
     case GenericArgument:
@@ -717,6 +718,20 @@ class LocatorPathElt::TypeParameterRequirement final
   }
 };
 
+class LocatorPathElt::ClosureBody final : public LocatorPathElt {
+  public:
+  ClosureBody(bool hasExplicitReturn = false)
+    : LocatorPathElt(ConstraintLocator::ClosureBody,
+                     hasExplicitReturn) {}
+
+  /// Indicates whether body of the closure has any `return` statements.
+  bool hasExplicitReturn() const { return bool(getValue(0)); }
+
+  static bool classof(const LocatorPathElt *elt) {
+    return elt->getKind() == ConstraintLocator::ClosureBody;
+  }
+};
+
 class LocatorPathElt::ContextualType final : public LocatorPathElt {
 public:
   ContextualType(bool isForSingleExprFunction = false)

lib/Sema/ConstraintLocatorPathElts.def

@@ -54,6 +54,9 @@ SIMPLE_LOCATOR_PATH_ELT(AutoclosureResult)
 /// The result of a closure.
 SIMPLE_LOCATOR_PATH_ELT(ClosureResult)
 
+/// The type of a closure body.
+CUSTOM_LOCATOR_PATH_ELT(ClosureBody)
+
 /// The lookup for a constructor member.
 SIMPLE_LOCATOR_PATH_ELT(ConstructorMember)