[AST] Make LifetimeDescriptor hold Identifier instead of StringRef

No reason to keep the name as a StringRef

Author: rintaro

include/swift/AST/DiagnosticsSema.def

@@ -8035,7 +8035,7 @@ ERROR(pack_iteration_where_clause_not_supported, none,
 //------------------------------------------------------------------------------
 
 ERROR(lifetime_dependence_invalid_param_name, none,
-      "invalid parameter name specified '%0'", (StringRef))
+      "invalid parameter name specified %0", (Identifier))
 ERROR(lifetime_dependence_invalid_param_index, none,
       "invalid parameter index specified '%0'", (unsigned))
 ERROR(lifetime_dependence_invalid_self_in_static, none,

include/swift/AST/LifetimeDependence.h

@@ -47,14 +47,14 @@ enum class LifetimeDependenceKind : uint8_t { Inherit = 0, Scope };
 struct LifetimeDescriptor {
   union Value {
     struct {
-      StringRef name;
+      Identifier name;
     } Named;
     struct {
       unsigned index;
     } Ordered;
     struct {
     } Self;
-    Value(StringRef name) : Named({name}) {}
+    Value(Identifier name) : Named({name}) {}
     Value(unsigned index) : Ordered({index}) {}
     Value() : Self() {}
   } value;
@@ -66,7 +66,7 @@ struct LifetimeDescriptor {
   SourceLoc loc;
 
 private:
-  LifetimeDescriptor(StringRef name,
+  LifetimeDescriptor(Identifier name,
                      ParsedLifetimeDependenceKind parsedLifetimeDependenceKind,
                      SourceLoc loc)
       : value{name}, kind(DescriptorKind::Named),
@@ -83,7 +83,7 @@ struct LifetimeDescriptor {
 
 public:
   static LifetimeDescriptor
-  forNamed(StringRef name,
+  forNamed(Identifier name,
            ParsedLifetimeDependenceKind parsedLifetimeDependenceKind,
            SourceLoc loc) {
     return {name, parsedLifetimeDependenceKind, loc};
@@ -104,7 +104,7 @@ struct LifetimeDescriptor {
     return parsedLifetimeDependenceKind;
   }
 
-  StringRef getName() const {
+  Identifier getName() const {
     assert(kind == DescriptorKind::Named);
     return value.Named.name;
   }
@@ -122,13 +122,13 @@ struct LifetimeDescriptor {
     if (getDescriptorKind() != LifetimeDescriptor::DescriptorKind::Named) {
       return false;
     }
-    return getName() == "immortal";
+    return getName().str() == "immortal";
   }
 
   std::string getString() const {
     switch (kind) {
     case DescriptorKind::Named:
-      return getName().str();
+      return getName().str().str();
     case DescriptorKind::Ordered:
       return std::to_string(getIndex());
     case DescriptorKind::Self:

lib/AST/Bridging/DeclAttributeBridging.cpp

@@ -376,9 +376,8 @@ unbridged(BridgedParsedLifetimeDependenceKind kind) {
 swift::LifetimeDescriptor BridgedLifetimeDescriptor::unbridged() {
   switch (kind) {
   case DescriptorKind::Named:
-    return LifetimeDescriptor::forNamed(value.name.unbridged().str(),
-                                        ::unbridged(dependenceKind),
-                                        loc.unbridged());
+    return LifetimeDescriptor::forNamed(
+        value.name.unbridged(), ::unbridged(dependenceKind), loc.unbridged());
   case DescriptorKind::Ordered:
     return LifetimeDescriptor::forOrdered(
         value.index, ::unbridged(dependenceKind), loc.unbridged());

lib/AST/LifetimeDependence.cpp

@@ -271,7 +271,7 @@ getParamDeclFromDescriptor(AbstractFunctionDecl *afd,
     unsigned paramIndex = 0;
     ParamDecl *candidateParam = nullptr;
     for (auto *param : *afd->getParameters()) {
-      if (param->getParameterName().str() == descriptor.getName()) {
+      if (param->getParameterName() == descriptor.getName()) {
         candidateParam = param;
         break;
       }

lib/Parse/ParseDecl.cpp

@@ -2480,8 +2480,7 @@ parseLifetimeDescriptor(Parser &P,
   case tok::identifier: {
     Identifier name;
     auto loc = P.consumeIdentifier(name, /*diagnoseDollarPrefix=*/false);
-    return LifetimeDescriptor::forNamed(name.str(), lifetimeDependenceKind,
-                                        loc);
+    return LifetimeDescriptor::forNamed(name, lifetimeDependenceKind, loc);
   }
   case tok::integer_literal: {
     SourceLoc loc;