Parse: Remove parse-time name lookup

Author: slavapestov

include/swift/Basic/LangOptions.h

@@ -258,9 +258,6 @@ namespace swift {
     /// This is a staging flag; eventually it will be removed.
     bool EnableDeserializationRecovery = true;
 
-    /// Someday, ASTScopeLookup will supplant lookup in the parser
-    bool DisableParserLookup = false;
-
     /// Whether to enable the new operator decl and precedencegroup lookup
     /// behavior. This is a staging flag, and will be removed in the future.
     bool EnableNewOperatorLookup = false;

include/swift/Option/Options.td

@@ -1118,14 +1118,6 @@ def emit_supported_features : Flag<["-"], "emit-supported-features">,
   HelpText<"Emit a JSON file including all supported compiler features">, ModeOpt,
   Flags<[FrontendOption, NoInteractiveOption, DoesNotAffectIncrementalBuild]>;
 
-def disable_parser_lookup : Flag<["-"], "disable-parser-lookup">,
-  Flags<[FrontendOption]>,
-  HelpText<"Disable parser lookup & use ASTScope lookup only (experimental)">;
-
-def enable_parser_lookup : Flag<["-"], "enable-parser-lookup">,
-  Flags<[FrontendOption]>,
-  HelpText<"Enable parser lookup">;
-
 def enable_request_based_incremental_dependencies : Flag<["-"],
   "enable-request-based-incremental-dependencies">,
   Flags<[FrontendOption]>,

include/swift/Parse/Parser.h

@@ -136,13 +136,6 @@ class Parser {
 
   void recordTokenHash(StringRef token);
 
-  /// DisabledVars is a list of variables for whom local name lookup is
-  /// disabled.  This is used when parsing a PatternBindingDecl to reject self
-  /// uses and to disable uses of the bound variables in a let/else block.  The
-  /// diagnostic to emit is stored in DisabledVarReason.
-  ArrayRef<VarDecl *> DisabledVars;
-  Diag<> DisabledVarReason;
-  
   enum {
     /// InVarOrLetPattern has this value when not parsing a pattern.
     IVOLP_NotInVarOrLet,
@@ -790,23 +783,6 @@ class Parser {
   consumeStartingCharacterOfCurrentToken(tok Kind = tok::oper_binary_unspaced,
                                          size_t Len = 1);
 
-  swift::ScopeInfo &getScopeInfo() { return State->getScopeInfo(); }
-
-  /// Add the given Decl to the current scope.
-  void addToScope(ValueDecl *D, bool diagnoseRedefinitions = true) {
-    if (Context.LangOpts.DisableParserLookup)
-      return;
-
-    getScopeInfo().addToScope(D, *this, diagnoseRedefinitions);
-  }
-
-  ValueDecl *lookupInScope(DeclNameRef Name) {
-    if (Context.LangOpts.DisableParserLookup)
-          return nullptr;
-
-    return getScopeInfo().lookupValueName(Name);
-  }
-
   //===--------------------------------------------------------------------===//
   // Primitive Parsing
 
@@ -1171,9 +1147,6 @@ class Parser {
   ParserResult<DestructorDecl>
   parseDeclDeinit(ParseDeclOptions Flags, DeclAttributes &Attributes);
 
-  void addPatternVariablesToScope(ArrayRef<Pattern *> Patterns);
-  void addParametersToScope(ParameterList *PL);
-
   ParserResult<OperatorDecl> parseDeclOperator(ParseDeclOptions Flags,
                                                DeclAttributes &Attributes);
   ParserResult<OperatorDecl> parseDeclOperatorImpl(SourceLoc OperatorLoc,
@@ -1224,8 +1197,7 @@ class Parser {
   ParserResult<TypeRepr> parseOldStyleProtocolComposition();
   ParserResult<TypeRepr> parseAnyType();
   ParserResult<TypeRepr> parseSILBoxType(GenericParamList *generics,
-                                         const TypeAttributes &attrs,
-                                         Optional<Scope> &GenericsScope);
+                                         const TypeAttributes &attrs);
 
   ParserResult<TypeRepr> parseTypeTupleBody();
   ParserResult<TypeRepr> parseTypeArray(TypeRepr *Base);

include/swift/Parse/PersistentParserState.h

@@ -19,7 +19,6 @@
 
 #include "swift/Basic/SourceLoc.h"
 #include "swift/Parse/LocalContext.h"
-#include "swift/Parse/Scope.h"
 
 namespace swift {
 
@@ -38,33 +37,27 @@ class CodeCompletionDelayedDeclState {
   CodeCompletionDelayedDeclKind Kind;
   unsigned Flags;
   DeclContext *ParentContext;
-  SavedScope Scope;
   unsigned StartOffset;
   unsigned EndOffset;
   unsigned PrevOffset;
 
-  SavedScope takeScope() { return std::move(Scope); }
-
   CodeCompletionDelayedDeclState(CodeCompletionDelayedDeclKind Kind,
                                  unsigned Flags, DeclContext *ParentContext,
-                                 SavedScope &&Scope, unsigned StartOffset,
-                                 unsigned EndOffset, unsigned PrevOffset)
+                                 unsigned StartOffset, unsigned EndOffset,
+                                 unsigned PrevOffset)
       : Kind(Kind), Flags(Flags), ParentContext(ParentContext),
-        Scope(std::move(Scope)), StartOffset(StartOffset), EndOffset(EndOffset),
+        StartOffset(StartOffset), EndOffset(EndOffset),
         PrevOffset(PrevOffset) {}
 };
 
 /// Parser state persistent across multiple parses.
 class PersistentParserState {
-  swift::ScopeInfo ScopeInfo;
-
   std::unique_ptr<CodeCompletionDelayedDeclState> CodeCompletionDelayedDeclStat;
 
   /// The local context for all top-level code.
   TopLevelContext TopLevelCode;
 
 public:
-  swift::ScopeInfo &getScopeInfo() { return ScopeInfo; }
   PersistentParserState();
   PersistentParserState(ASTContext &ctx) : PersistentParserState() { }
   ~PersistentParserState();

include/swift/Parse/Scope.h

@@ -268,8 +268,6 @@ void ToolChain::addCommonFrontendArgs(const OutputInfo &OI,
   inputArgs.AddLastArg(arguments, options::OPT_debug_diagnostic_names);
   inputArgs.AddLastArg(arguments, options::OPT_print_educational_notes);
   inputArgs.AddLastArg(arguments, options::OPT_diagnostic_style);
-  inputArgs.AddLastArg(arguments, options::OPT_disable_parser_lookup);
-  inputArgs.AddLastArg(arguments, options::OPT_enable_parser_lookup);
   inputArgs.AddLastArg(arguments,
                        options::OPT_enable_experimental_concise_pound_file);
   inputArgs.AddLastArg(

lib/Driver/ToolChains.cpp

@@ -434,9 +434,6 @@ static bool ParseLangArgs(LangOptions &Opts, ArgList &Args,
       = A->getOption().matches(OPT_enable_target_os_checking);
   }
 
-  Opts.DisableParserLookup |= Args.hasFlag(OPT_disable_parser_lookup,
-                                           OPT_enable_parser_lookup,
-                                           /*default*/ true);
   Opts.EnableNewOperatorLookup = Args.hasFlag(OPT_enable_new_operator_lookup,
                                               OPT_disable_new_operator_lookup,
                                               /*default*/ false);

lib/Frontend/CompilerInvocation.cpp

@@ -366,7 +366,6 @@ bool CompletionInstance::performCachedOperationIfPossible(
   tmpSM.setCodeCompletionPoint(tmpBufferID, Offset);
 
   LangOptions langOpts = CI.getASTContext().LangOpts;
-  langOpts.DisableParserLookup = true;
   TypeCheckerOptions typeckOpts = CI.getASTContext().TypeCheckerOpts;
   SearchPathOptions searchPathOpts = CI.getASTContext().SearchPathOpts;
   DiagnosticEngine tmpDiags(tmpSM);
@@ -444,17 +443,6 @@ bool CompletionInstance::performCachedOperationIfPossible(
                            1);
     SM.setCodeCompletionPoint(newBufferID, newOffset);
 
-    // Construct dummy scopes. We don't need to restore the original scope
-    // because they are probably not 'isResolvable()' anyway.
-    auto &SI = oldState->getScopeInfo();
-    assert(SI.getCurrentScope() == nullptr);
-    Scope Top(SI, ScopeKind::TopLevel);
-    Scope Body(SI, ScopeKind::FunctionBody);
-
-    assert(oldInfo.Kind == CodeCompletionDelayedDeclKind::FunctionBody &&
-           "If the interface hash is the same as old one, the previous kind "
-           "must be FunctionBody too. Otherwise, hashing is too weak");
-    oldInfo.Kind = CodeCompletionDelayedDeclKind::FunctionBody;
     oldInfo.ParentContext = DC;
     oldInfo.StartOffset = newInfo.StartOffset;
     oldInfo.EndOffset = newInfo.EndOffset;

lib/IDE/CompletionInstance.cpp

@@ -22,7 +22,6 @@ add_swift_host_library(swiftParse STATIC
   ParseStmt.cpp
   ParseType.cpp
   PersistentParserState.cpp
-  Scope.cpp
   SyntaxParsingCache.cpp
   SyntaxParsingContext.cpp)
 _swift_gyb_target_sources(swiftParse PRIVATE