[ConstraintSystem] Adjust ConformanceRequirement locator to carry ProtocolConformance

Author: xedin

include/swift/Sema/ConstraintLocator.h

@@ -39,6 +39,7 @@ class TypeLoc;
 class VarDecl;
 class Pattern;
 class SourceManager;
+class ProtocolConformance;
 
 namespace constraints {
 
@@ -763,13 +764,13 @@ class LocatorPathElt::ArgumentAttribute final : public StoredIntegerElement<1> {
 };
 
 class LocatorPathElt::ConformanceRequirement final
-    : public StoredPointerElement<ProtocolDecl> {
+    : public StoredPointerElement<ProtocolConformance> {
 public:
-  ConformanceRequirement(ProtocolDecl *protocol)
+  ConformanceRequirement(ProtocolConformance *conformance)
       : StoredPointerElement(PathElementKind::ConformanceRequirement,
-                             protocol) {}
+                             conformance) {}
 
-  ProtocolDecl *getRequirement() const { return getStoredPointer(); }
+  ProtocolConformance *getConformance() const { return getStoredPointer(); }
 
   static bool classof(const LocatorPathElt *elt) {
     return elt->getKind() == ConstraintLocator::ConformanceRequirement;

lib/Sema/ConstraintLocator.cpp

@@ -18,6 +18,7 @@
 #include "swift/AST/Decl.h"
 #include "swift/AST/Expr.h"
 #include "swift/AST/Types.h"
+#include "swift/AST/ProtocolConformance.h"
 #include "swift/Sema/ConstraintLocator.h"
 #include "swift/Sema/ConstraintSystem.h"
 #include "llvm/ADT/StringExtras.h"
@@ -399,9 +400,10 @@ void ConstraintLocator::dump(SourceManager *sm, raw_ostream &out) const {
     }
 
     case ConformanceRequirement: {
-      auto reqElt = elt.castTo<LocatorPathElt::ConformanceRequirement>();
+      auto *conformance =
+          elt.castTo<LocatorPathElt::ConformanceRequirement>().getConformance();
       out << "conformance requirement (";
-      reqElt.getRequirement()->dumpRef(out);
+      conformance->getProtocol()->dumpRef(out);
       out << ")";
       break;
     }