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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 frontend_BytecodeCompiler_h
+#define frontend_BytecodeCompiler_h
+
+#include "mozilla/Maybe.h"
+#include "mozilla/Utf8.h"  // mozilla::Utf8Unit
+
+#include "NamespaceImports.h"
+
+#include "ds/LifoAlloc.h"
+#include "frontend/FunctionSyntaxKind.h"
+#include "js/SourceText.h"
+#include "js/UniquePtr.h"  // js::UniquePtr
+
+/*
+ * Structure of all of the support classes.
+ *
+ * Parser: described in Parser.h.
+ *
+ * BytecodeCompiler.cpp: BytecodeCompiler.h *and* BytecodeCompilation.h.
+ * This is the "driver", the high-level operations like "compile this source to
+ * bytecode". It calls the parser, bytecode emitter, etc.
+ *
+ * ParseContext.h and SharedContext.h: Both have similar purposes. They're split
+ * because ParseContext contains information used only by the parser, and
+ * SharedContext contains information used by both the parser and
+ * BytecodeEmitter.
+ *
+ * SharedContext.h: class Directives: this contains boolean flags for tracking
+ * if we're in asm.js or "use strict" code. The "use strict" bit is stored in
+ * SharedContext, and additionally, the full Directives class is stored in
+ * ParseContext - if a direcive is encountered while parsing, this is updated,
+ * and checked in GeneralParser::functionDefinition, and if it changed, the
+ * whole function is re-parsed with the new flags.
+ *
+ * SharedContext.h: abstract class SharedContext: This class contains two
+ * different groups of flags:
+ *
+ * Parse context information. This is information conceptually "passed down"
+ * into parsing sub-nodes. This is like "are we parsing strict code?", and so
+ * the parser can make decisions of how to parse based off that.
+ *
+ * Gathered-while-parsing information. This is information conceptually
+ * "returned up" from parsing sub-nodes. This is like "did we see a use strict
+ * directive"?
+ *
+ * Additionally, subclasses (GlobalSharedContext, ModuleSharedContext,
+ * EvalSharedContext, and FunctionBox) contain binding information, scope
+ * information, and other such bits of data.
+ *
+ * ParseContext.h: class UsedNameTracker: Track which bindings are used in which
+ * scopes. This helps determine which bindings are closed-over, which affects
+ * how they're stored; and whether special bindings like `this` and `arguments`
+ * can be optimized away.
+ *
+ * ParseContext.h: class ParseContext: Extremely complex class that serves a lot
+ * of purposes, but it's a single class - essentially no derived classes - so
+ * it's a little easier to comprehend all at once. (SourceParseContext does
+ * derive from ParseContext, but they does nothing except adjust the
+ * constructor's arguments).
+ * Note it uses a thing called Nestable, which implements a stack of objects:
+ * you can push (and pop) instances to a stack (linked list) as you parse
+ * further into the parse tree. You may push to this stack via calling the
+ * constructor with a GeneralParser as an argument (usually `this`), which
+ * pushes itself onto `this->pc` (so it does get assigned/pushed, even though no
+ * assignment ever appears directly in the parser)
+ *
+ * ParseContext contains a pointer to a SharedContext.
+ *
+ * There's a decent chunk of flags/data collection in here too, some "pass-down"
+ * data and some "return-up" data.
+ *
+ * ParseContext also contains a significant number of *sub*-Nestables as fields
+ * of itself (nestables inside nestables). Note you also push/pop to these via
+ * passing `Parser->pc`, which the constructor of the sub-nestable knows which
+ * ParseContext field to push to. The sub-nestables are:
+ *
+ * ParseContext::Statement: stack of statements.
+ * `if (x) { while (true) { try { ..stack of [if, while, try].. } ... } }`
+ *
+ * ParseContext::LabelStatement: interspersed in Statement stack, for labeled
+ * statements, for e.g. `label: while (true) { break label; }`
+ *
+ * ParseContext::ClassStatement: interspersed in Statement stack, for classes
+ * the parser is currently inside of.
+ *
+ * ParseContext::Scope: Set of variables in each scope (stack of sets):
+ * `{ let a; let b; { let c; } }`
+ * (this gets complicated with `var`, etc., check the class for docs)
+ */
+
+class JSLinearString;
+
+namespace JS {
+class JS_PUBLIC_API ReadOnlyCompileOptions;
+}
+
+namespace js {
+
+class ModuleObject;
+class ScriptSourceObject;
+class FrontendContext;
+
+namespace frontend {
+
+struct CompilationInput;
+struct CompilationStencil;
+struct ExtensibleCompilationStencil;
+struct CompilationGCOutput;
+class ErrorReporter;
+class FunctionBox;
+class ParseNode;
+class TaggedParserAtomIndex;
+class ScopeBindingCache;
+
+// Compile a module of the given source using the given options.
+ModuleObject* CompileModule(JSContext* cx, FrontendContext* fc,
+                            const JS::ReadOnlyCompileOptions& options,
+                            JS::SourceText<char16_t>& srcBuf);
+ModuleObject* CompileModule(JSContext* cx, FrontendContext* fc,
+                            const JS::ReadOnlyCompileOptions& options,
+                            JS::SourceText<mozilla::Utf8Unit>& srcBuf);
+
+// Parse a module of the given source.  This is an internal API; if you want to
+// compile a module as a user, use CompileModule above.
+already_AddRefed<CompilationStencil> ParseModuleToStencil(
+    JSContext* maybeCx, FrontendContext* fc, js::LifoAlloc& tempLifoAlloc,
+    CompilationInput& input, ScopeBindingCache* scopeCache,
+    JS::SourceText<char16_t>& srcBuf);
+already_AddRefed<CompilationStencil> ParseModuleToStencil(
+    JSContext* maybeCx, FrontendContext* fc, js::LifoAlloc& tempLifoAlloc,
+    CompilationInput& input, ScopeBindingCache* scopeCache,
+    JS::SourceText<mozilla::Utf8Unit>& srcBuf);
+
+UniquePtr<ExtensibleCompilationStencil> ParseModuleToExtensibleStencil(
+    JSContext* cx, FrontendContext* fc, js::LifoAlloc& tempLifoAlloc,
+    CompilationInput& input, ScopeBindingCache* scopeCache,
+    JS::SourceText<char16_t>& srcBuf);
+UniquePtr<ExtensibleCompilationStencil> ParseModuleToExtensibleStencil(
+    JSContext* cx, FrontendContext* fc, js::LifoAlloc& tempLifoAlloc,
+    CompilationInput& input, ScopeBindingCache* scopeCache,
+    JS::SourceText<mozilla::Utf8Unit>& srcBuf);
+
+//
+// Compile a single function. The source in srcBuf must match the ECMA-262
+// FunctionExpression production.
+//
+// If nonzero, parameterListEnd is the offset within srcBuf where the parameter
+// list is expected to end. During parsing, if we find that it ends anywhere
+// else, it's a SyntaxError. This is used to implement the Function constructor;
+// it's how we detect that these weird cases are SyntaxErrors:
+//
+//     Function("/*", "*/x) {")
+//     Function("x){ if (3", "return x;}")
+//
+[[nodiscard]] JSFunction* CompileStandaloneFunction(
+    JSContext* cx, const JS::ReadOnlyCompileOptions& options,
+    JS::SourceText<char16_t>& srcBuf,
+    const mozilla::Maybe<uint32_t>& parameterListEnd,
+    frontend::FunctionSyntaxKind syntaxKind);
+
+[[nodiscard]] JSFunction* CompileStandaloneGenerator(
+    JSContext* cx, const JS::ReadOnlyCompileOptions& options,
+    JS::SourceText<char16_t>& srcBuf,
+    const mozilla::Maybe<uint32_t>& parameterListEnd,
+    frontend::FunctionSyntaxKind syntaxKind);
+
+[[nodiscard]] JSFunction* CompileStandaloneAsyncFunction(
+    JSContext* cx, const JS::ReadOnlyCompileOptions& options,
+    JS::SourceText<char16_t>& srcBuf,
+    const mozilla::Maybe<uint32_t>& parameterListEnd,
+    frontend::FunctionSyntaxKind syntaxKind);
+
+[[nodiscard]] JSFunction* CompileStandaloneAsyncGenerator(
+    JSContext* cx, const JS::ReadOnlyCompileOptions& options,
+    JS::SourceText<char16_t>& srcBuf,
+    const mozilla::Maybe<uint32_t>& parameterListEnd,
+    frontend::FunctionSyntaxKind syntaxKind);
+
+// Compile a single function in given enclosing non-syntactic scope.
+[[nodiscard]] JSFunction* CompileStandaloneFunctionInNonSyntacticScope(
+    JSContext* cx, const JS::ReadOnlyCompileOptions& options,
+    JS::SourceText<char16_t>& srcBuf,
+    const mozilla::Maybe<uint32_t>& parameterListEnd,
+    frontend::FunctionSyntaxKind syntaxKind, Handle<Scope*> enclosingScope);
+
+/*
+ * True if str consists of an IdentifierStart character, followed by one or
+ * more IdentifierPart characters, i.e. it matches the IdentifierName production
+ * in the language spec.
+ *
+ * This returns true even if str is a keyword like "if".
+ *
+ * Defined in TokenStream.cpp.
+ */
+bool IsIdentifier(JSLinearString* str);
+
+bool IsIdentifierNameOrPrivateName(JSLinearString* str);
+
+/*
+ * As above, but taking chars + length.
+ */
+bool IsIdentifier(const Latin1Char* chars, size_t length);
+bool IsIdentifier(const char16_t* chars, size_t length);
+
+/*
+ * ASCII variant with known length.
+ */
+bool IsIdentifierASCII(char c);
+bool IsIdentifierASCII(char c1, char c2);
+
+bool IsIdentifierNameOrPrivateName(const Latin1Char* chars, size_t length);
+bool IsIdentifierNameOrPrivateName(const char16_t* chars, size_t length);
+
+/* True if str is a keyword. Defined in TokenStream.cpp. */
+bool IsKeyword(TaggedParserAtomIndex atom);
+
+} /* namespace frontend */
+} /* namespace js */
+
+#endif /* frontend_BytecodeCompiler_h */