1 files changed, 123 insertions, 0 deletions
diff --git a/js/src/vm/ModuleBuilder.h b/js/src/vm/ModuleBuilder.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef vm_ModuleBuilder_h
+#define vm_ModuleBuilder_h
+
+#include "mozilla/Attributes.h"  // MOZ_STACK_CLASS
+
+#include "jstypes.h"               // JS_PUBLIC_API
+#include "builtin/ModuleObject.h"  // js::{{Im,Ex}portEntry,Requested{Module,}}Object
+#include "frontend/EitherParser.h"  // js::frontend::EitherParser
+#include "frontend/ParserAtom.h"  // js::frontend::{ParserAtom, TaggedParserAtomIndex}
+#include "frontend/Stencil.h"  // js::frontend::StencilModuleEntry
+#include "js/GCHashTable.h"    // JS::GCHash{Map,Set}
+#include "js/GCVector.h"       // JS::GCVector
+#include "js/RootingAPI.h"     // JS::{Handle,Rooted}
+#include "vm/AtomsTable.h"     // js::AtomSet
+
+struct JS_PUBLIC_API JSContext;
+class JS_PUBLIC_API JSAtom;
+
+namespace js {
+
+namespace frontend {
+
+class BinaryNode;
+class ListNode;
+class ParseNode;
+
+}  // namespace frontend
+
+class TaggedParserAtomIndexHasher {
+ public:
+  using Lookup = frontend::TaggedParserAtomIndex;
+
+  static inline HashNumber hash(const Lookup& l) {
+    return HashNumber(
+        *const_cast<frontend::TaggedParserAtomIndex&>(l).rawData());
+  }
+  static inline bool match(frontend::TaggedParserAtomIndex entry,
+                           const Lookup& l) {
+    return l == entry;
+  }
+};
+
+// Process a module's parse tree to collate the import and export data used when
+// creating a ModuleObject.
+class MOZ_STACK_CLASS ModuleBuilder {
+  explicit ModuleBuilder(JSContext* cx,
+                         const frontend::EitherParser& eitherParser);
+
+ public:
+  template <class Parser>
+  explicit ModuleBuilder(JSContext* cx, Parser* parser)
+      : ModuleBuilder(cx, frontend::EitherParser(parser)) {}
+
+  bool processImport(frontend::BinaryNode* importNode);
+  bool processExport(frontend::ParseNode* exportNode);
+  bool processExportFrom(frontend::BinaryNode* exportNode);
+
+  bool hasExportedName(const frontend::ParserAtom* name) const;
+
+  bool buildTables(frontend::StencilModuleMetadata& metadata);
+
+  // During BytecodeEmitter we note top-level functions, and afterwards we must
+  // call finishFunctionDecls on the list.
+  bool noteFunctionDeclaration(JSContext* cx, uint32_t funIndex);
+  void finishFunctionDecls(frontend::StencilModuleMetadata& metadata);
+
+  void noteAsync(frontend::StencilModuleMetadata& metadata);
+
+ private:
+  using RequestedModuleVector =
+      Vector<frontend::StencilModuleEntry, 0, js::SystemAllocPolicy>;
+  using AtomSet = HashSet<const frontend::ParserAtom*>;
+  using ExportEntryVector = Vector<frontend::StencilModuleEntry>;
+  using ImportEntryMap =
+      HashMap<frontend::TaggedParserAtomIndex, frontend::StencilModuleEntry,
+              TaggedParserAtomIndexHasher>;
+
+  JSContext* cx_;
+  frontend::EitherParser eitherParser_;
+
+  // These are populated while parsing.
+  AtomSet requestedModuleSpecifiers_;
+  RequestedModuleVector requestedModules_;
+  ImportEntryMap importEntries_;
+  ExportEntryVector exportEntries_;
+  AtomSet exportNames_;
+
+  // These are populated while emitting bytecode.
+  frontend::FunctionDeclarationVector functionDecls_;
+
+  frontend::StencilModuleEntry* importEntryFor(
+      frontend::TaggedParserAtomIndex localName) const;
+
+  bool processExportBinding(frontend::ParseNode* pn);
+  bool processExportArrayBinding(frontend::ListNode* array);
+  bool processExportObjectBinding(frontend::ListNode* obj);
+
+  bool appendExportEntry(const frontend::ParserAtom* exportName,
+                         const frontend::ParserAtom* localName,
+                         frontend::ParseNode* node = nullptr);
+
+  bool appendExportFromEntry(const frontend::ParserAtom* exportName,
+                             const frontend::ParserAtom* moduleRequest,
+                             const frontend::ParserAtom* importName,
+                             frontend::ParseNode* node);
+
+  bool maybeAppendRequestedModule(const frontend::ParserAtom* specifier,
+                                  frontend::ParseNode* node);
+};
+
+template <typename T>
+ArrayObject* CreateArray(JSContext* cx,
+                         const JS::Rooted<JS::GCVector<T>>& vector);
+
+}  // namespace js
+
+#endif  // vm_ModuleBuilder_h