NFC: Rename NameBinding to ImportResolution (swiftlang#30717)

NFC: Rename NameBinding to ImportResolution

Author: hamishknight

docs/CompilerPerformance.md

@@ -570,7 +570,7 @@ compilers on hand while you're working.
     Total Execution Time: 0.0876 seconds (0.0877 wall clock)
 
      ---User Time---   --System Time--   --User+System--   ---Wall Time---  --- Name ---
-     0.0241 ( 53.9%)   0.0394 ( 92.0%)   0.0635 ( 72.5%)   0.0635 ( 72.5%)  Name binding
+     0.0241 ( 53.9%)   0.0394 ( 92.0%)   0.0635 ( 72.5%)   0.0635 ( 72.5%)  Import resolution
      0.0170 ( 38.0%)   0.0025 (  5.8%)   0.0195 ( 22.3%)   0.0195 ( 22.2%)  Type checking / Semantic analysis
      0.0013 (  3.0%)   0.0004 (  0.8%)   0.0017 (  1.9%)   0.0017 (  1.9%)  LLVM output
      0.0010 (  2.3%)   0.0003 (  0.7%)   0.0013 (  1.5%)   0.0013 (  1.5%)  SILGen

include/swift/AST/DiagnosticsSema.def

@@ -661,7 +661,7 @@ NOTE(add_return_type_note,none,
      "did you mean to add a return type?", ())
 
 //------------------------------------------------------------------------------
-// MARK: Name Binding
+// MARK: Import Resolution
 //------------------------------------------------------------------------------
 
 ERROR(sema_no_import,Fatal,

include/swift/AST/Expr.h

@@ -1333,9 +1333,9 @@ class SuperRefExpr : public Expr {
   }
 };
 
-/// A reference to a type in expression context, spelled out as a TypeLoc. Sema
-/// forms this expression as a result of name binding.  This always has
-/// MetaTypetype.
+/// A reference to a type in expression context, spelled out as a TypeLoc.
+///
+/// The type of this expression is always \c MetaTypeType.
 class TypeExpr : public Expr {
   TypeLoc Info;
   TypeExpr(Type Ty);
@@ -4831,7 +4831,7 @@ class AssignExpr : public Expr {
 };
 
 /// A pattern production that has been parsed but hasn't been resolved
-/// into a complete pattern. Name binding converts these into standalone pattern
+/// into a complete pattern. Pattern checking converts these into standalone pattern
 /// nodes or raises an error if a pattern production appears in an invalid
 /// position.
 class UnresolvedPatternExpr : public Expr {

include/swift/AST/ImportCache.h

@@ -148,7 +148,7 @@ class alignas(ModuleDecl::ImportedModule) ImportCache {
                                  const DeclContext *dc);
 
   /// This is a hack to cope with main file parsing and REPL parsing, where
-  /// we can add ImportDecls after name binding.
+  /// we can add ImportDecls after import resolution.
   void clear() {
     ImportSetForDC.clear();
   }

include/swift/AST/SourceFile.h

@@ -23,9 +23,8 @@ class PersistentParserState;
 /// A file containing Swift source code.
 ///
 /// This is a .swift or .sil file (or a virtual file, such as the contents of
-/// the REPL). Since it contains raw source, it must be parsed and name-bound
-/// before being used for anything; a full type-check is also necessary for
-/// IR generation.
+/// the REPL). Since it contains raw source, it must be type checked for IR
+/// generation.
 class SourceFile final : public FileUnit {
   friend class ParseSourceFileRequest;
 
@@ -128,7 +127,7 @@ class SourceFile final : public FileUnit {
 
   /// This is the list of modules that are imported by this module.
   ///
-  /// This is filled in by the Name Binding phase.
+  /// This is filled in by the import resolution phase.
   ArrayRef<ImportedModuleDesc> Imports;
 
   /// A unique identifier representing this file; used to mark private decls
@@ -316,10 +315,10 @@ class SourceFile final : public FileUnit {
   const SourceFileKind Kind;
 
   enum ASTStage_t {
-    /// The source file is not name bound or type checked.
+    /// The source file has not had its imports resolved or been type checked.
     Unprocessed,
-    /// Name binding has completed.
-    NameBound,
+    /// Import resolution has completed.
+    ImportsResolved,
     /// Type checking has completed.
     TypeChecked
   };

include/swift/AST/TypeRepr.h

@@ -263,7 +263,7 @@ class ComponentIdentTypeRepr : public IdentTypeRepr {
   /// component.
   ///
   /// The initial parsed representation is always an identifier, and
-  /// name binding will resolve this to a specific declaration.
+  /// name lookup will resolve this to a specific declaration.
   llvm::PointerUnion<DeclNameRef, TypeDecl *> IdOrDecl;
 
   /// The declaration context from which the bound declaration was
@@ -282,7 +282,8 @@ class ComponentIdentTypeRepr : public IdentTypeRepr {
   /// correction.
   void overwriteNameRef(DeclNameRef newId) { IdOrDecl = newId; }
 
-  /// Return true if this has been name-bound already.
+  /// Return true if this name has been resolved to a type decl. This happens
+  /// during type resolution.
   bool isBound() const { return IdOrDecl.is<TypeDecl *>(); }
 
   TypeDecl *getBoundDecl() const { return IdOrDecl.dyn_cast<TypeDecl*>(); }

include/swift/AST/Types.h

@@ -1271,10 +1271,11 @@ class NominalOrBoundGenericNominalType : public AnyGenericType {
 };
 DEFINE_EMPTY_CAN_TYPE_WRAPPER(NominalOrBoundGenericNominalType, AnyGenericType)
 
-/// ErrorType - This represents a type that was erroneously constructed.  This
-/// is produced when parsing types and when name binding type aliases, and is
-/// installed in declaration that use these erroneous types.  All uses of a
-/// declaration of invalid type should be ignored and not re-diagnosed.
+/// ErrorType - Represents the type of an erroneously constructed declaration,
+/// expression, or type. When creating ErrorTypes, an associated error
+/// diagnostic should always be emitted. That way when later stages of
+/// compilation encounter an ErrorType installed by earlier phases they do not
+/// have to emit further diagnostics to abort compilation.
 class ErrorType final : public TypeBase {
   friend class ASTContext;
   // The Error type is always canonical.
@@ -6410,11 +6411,11 @@ inline ArrayRef<AnyFunctionType::Param> AnyFunctionType::getParams() const {
     llvm_unreachable("Undefined function type");
   }
 }
-  
+
 /// If this is a method in a type or extension thereof, compute
 /// and return a parameter to be used for the 'self' argument.  The type of
 /// the parameter is the empty Type() if no 'self' argument should exist. This
-/// can only be used after name binding has resolved types.
+/// can only be used after types have been resolved.
 ///
 /// \param isInitializingCtor Specifies whether we're computing the 'self'
 /// type of an initializing constructor, which accepts an instance 'self'

include/swift/Frontend/Frontend.h

@@ -623,7 +623,7 @@ class CompilerInstance {
   void performParseOnly(bool EvaluateConditionals = false,
                         bool CanDelayBodies = true);
 
-  /// Parses and performs name binding on all input files.
+  /// Parses and performs import resolution on all input files.
   ///
   /// This is similar to a parse-only invocation, but module imports will also
   /// be processed.

include/swift/Parse/Scope.h

@@ -170,7 +170,7 @@ inline ValueDecl *ScopeInfo::lookupValueName(DeclNameRef Name) {
   assert(CurScope && "no scope");
   // If we found nothing, or we found a decl at the top-level, return nothing.
   // We ignore results at the top-level because we may have overloading that
-  // will be resolved properly by name binding.
+  // will be resolved properly by name lookup.
   std::pair<unsigned, ValueDecl *> Res = HT.lookup(CurScope->HTScope,
                                                    Name.getFullName());
   if (Res.first < ResolvableDepth)

include/swift/Subsystems.h

@@ -118,33 +118,32 @@ namespace swift {
                               bool TokenizeInterpolatedString = true,
                               ArrayRef<Token> SplitTokens = ArrayRef<Token>());
 
-  /// Once parsing is complete, this walks the AST to resolve imports, record
-  /// operators, and do other top-level validation.
-  void performNameBinding(SourceFile &SF);
+  /// This walks the AST to resolve imports.
+  void performImportResolution(SourceFile &SF);
 
   /// Once type-checking is complete, this instruments code with calls to an
   /// intrinsic that record the expected values of local variables so they can
   /// be compared against the results from the debugger.
   void performDebuggerTestingTransform(SourceFile &SF);
 
-  /// Once parsing and name-binding are complete, this optionally transforms the
-  /// ASTs to add calls to external logging functions.
+  /// Once type checking is complete, this optionally transforms the ASTs to add
+  /// calls to external logging functions.
   ///
   /// \param HighPerformance True if the playground transform should omit
   /// instrumentation that has a high runtime performance impact.
   void performPlaygroundTransform(SourceFile &SF, bool HighPerformance);
 
-  /// Once parsing and name-binding are complete this optionally walks the ASTs
-  /// to add calls to externally provided functions that simulate
-  /// "program counter"-like debugging events. See the comment at the top of
-  /// lib/Sema/PCMacro.cpp for a description of the calls inserted.
+  /// Once type checking is complete this optionally walks the ASTs to add calls
+  /// to externally provided functions that simulate "program counter"-like
+  /// debugging events. See the comment at the top of lib/Sema/PCMacro.cpp for a
+  /// description of the calls inserted.
   void performPCMacro(SourceFile &SF);
 
   /// Bind all 'extension' visible from \p SF to the extended nominal.
   void bindExtensions(SourceFile &SF);
 
-  /// Once parsing and name-binding are complete, this walks the AST to resolve
-  /// types and diagnose problems therein.
+  /// Once import resolution is complete, this walks the AST to resolve types
+  /// and diagnose problems therein.
   void performTypeChecking(SourceFile &SF);
 
   /// Now that we have type-checked an entire module, perform any type