1 files changed, 118 insertions, 0 deletions
diff --git a/js/src/vm/ModuleBuilder.h b/js/src/vm/ModuleBuilder.h
new file mode 100644
index 0000000000..3716a6cdd2
--- /dev/null
+++ b/js/src/vm/ModuleBuilder.h
@@ -0,0 +1,118 @@
+/* -*- 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 "frontend/EitherParser.h"  // js::frontend::EitherParser
+#include "frontend/ParserAtom.h"    // js::frontend::TaggedParserAtomIndex
+#include "frontend/Stencil.h"       // js::frontend::StencilModuleEntry
+#include "frontend/TaggedParserAtomIndexHasher.h"  // frontend::TaggedParserAtomIndexHasher
+#include "js/GCVector.h"                           // JS::GCVector
+
+struct JS_PUBLIC_API JSContext;
+class JS_PUBLIC_API JSAtom;
+
+namespace js {
+
+namespace frontend {
+
+class BinaryNode;
+class ListNode;
+class ParseNode;
+
+}  // namespace frontend
+
+// 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(FrontendContext* fc,
+                         const frontend::EitherParser& eitherParser);
+
+ public:
+  template <class Parser>
+  explicit ModuleBuilder(FrontendContext* fc, Parser* parser)
+      : ModuleBuilder(fc, frontend::EitherParser(parser)) {}
+
+  bool processImport(frontend::BinaryNode* importNode);
+  bool processExport(frontend::ParseNode* exportNode);
+  bool processExportFrom(frontend::BinaryNode* exportNode);
+
+  bool hasExportedName(frontend::TaggedParserAtomIndex 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(FrontendContext* fc, uint32_t funIndex);
+  void finishFunctionDecls(frontend::StencilModuleMetadata& metadata);
+
+  void noteAsync(frontend::StencilModuleMetadata& metadata);
+
+ private:
+  using MaybeModuleRequestIndex = frontend::MaybeModuleRequestIndex;
+  using ModuleRequestVector = frontend::StencilModuleMetadata::RequestVector;
+  using RequestedModuleVector = frontend::StencilModuleMetadata::EntryVector;
+
+  using AtomSet = HashSet<frontend::TaggedParserAtomIndex,
+                          frontend::TaggedParserAtomIndexHasher>;
+  using ExportEntryVector = Vector<frontend::StencilModuleEntry>;
+  using ImportEntryMap =
+      HashMap<frontend::TaggedParserAtomIndex, frontend::StencilModuleEntry,
+              frontend::TaggedParserAtomIndexHasher>;
+
+  FrontendContext* fc_;
+  frontend::EitherParser eitherParser_;
+
+  // These are populated while parsing.
+  ModuleRequestVector moduleRequests_;
+  AtomSet requestedModuleSpecifiers_;
+  RequestedModuleVector requestedModules_;
+  ImportEntryMap importEntries_;
+  ExportEntryVector exportEntries_;
+  AtomSet exportNames_;
+
+  // These are populated while emitting bytecode.
+  FunctionDeclarationVector functionDecls_;
+
+  frontend::StencilModuleEntry* importEntryFor(
+      frontend::TaggedParserAtomIndex localName) const;
+
+  bool processExportBinding(frontend::ParseNode* binding);
+  bool processExportArrayBinding(frontend::ListNode* array);
+  bool processExportObjectBinding(frontend::ListNode* obj);
+
+  MaybeModuleRequestIndex appendModuleRequest(
+      frontend::TaggedParserAtomIndex specifier,
+      frontend::ListNode* assertionList);
+
+  bool appendExportEntry(frontend::TaggedParserAtomIndex exportName,
+                         frontend::TaggedParserAtomIndex localName,
+                         frontend::ParseNode* node = nullptr);
+
+  bool maybeAppendRequestedModule(MaybeModuleRequestIndex moduleRequest,
+                                  frontend::ParseNode* node);
+
+  void markUsedByStencil(frontend::TaggedParserAtomIndex name);
+
+  [[nodiscard]] bool processAssertions(frontend::StencilModuleRequest& request,
+                                       frontend::ListNode* assertionList);
+
+  [[nodiscard]] bool isAssertionSupported(
+      JS::ImportAssertion supportedAssertion,
+      frontend::TaggedParserAtomIndex key);
+};
+
+template <typename T>
+ArrayObject* CreateArray(JSContext* cx,
+                         const JS::Rooted<JS::GCVector<T>>& vector);
+
+}  // namespace js
+
+#endif  // vm_ModuleBuilder_h