/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * vim: set ts=8 sts=4 et sw=4 tw=99: * 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 jsfuninlines_h #define jsfuninlines_h #include "jsfun.h" #include "vm/EnvironmentObject.h" namespace js { inline const char* GetFunctionNameBytes(JSContext* cx, JSFunction* fun, JSAutoByteString* bytes) { if (JSAtom* name = fun->explicitName()) return bytes->encodeLatin1(cx, name); return js_anonymous_str; } static inline JSObject* SkipEnvironmentObjects(JSObject* env) { if (!env) return nullptr; while (env->is<EnvironmentObject>()) env = &env->as<EnvironmentObject>().enclosingEnvironment(); return env; } inline bool CanReuseFunctionForClone(JSContext* cx, HandleFunction fun) { if (!fun->isSingleton()) return false; if (fun->isInterpretedLazy()) { LazyScript* lazy = fun->lazyScript(); if (lazy->hasBeenCloned()) return false; lazy->setHasBeenCloned(); } else { JSScript* script = fun->nonLazyScript(); if (script->hasBeenCloned()) return false; script->setHasBeenCloned(); } return true; } inline JSFunction* CloneFunctionObjectIfNotSingleton(JSContext* cx, HandleFunction fun, HandleObject parent, HandleObject proto = nullptr, NewObjectKind newKind = GenericObject) { /* * For attempts to clone functions at a function definition opcode, * try to avoid the the clone if the function has singleton type. This * was called pessimistically, and we need to preserve the type's * property that if it is singleton there is only a single object * with its type in existence. * * For functions inner to run once lambda, it may be possible that * the lambda runs multiple times and we repeatedly clone it. In these * cases, fall through to CloneFunctionObject, which will deep clone * the function's script. */ if (CanReuseFunctionForClone(cx, fun)) { RootedObject obj(cx, SkipEnvironmentObjects(parent)); ObjectOpResult succeeded; if (proto && !SetPrototype(cx, fun, proto, succeeded)) return nullptr; MOZ_ASSERT(!proto || succeeded); fun->setEnvironment(parent); return fun; } // These intermediate variables are needed to avoid link errors on some // platforms. Sigh. gc::AllocKind finalizeKind = gc::AllocKind::FUNCTION; gc::AllocKind extendedFinalizeKind = gc::AllocKind::FUNCTION_EXTENDED; gc::AllocKind kind = fun->isExtended() ? extendedFinalizeKind : finalizeKind; if (CanReuseScriptForClone(cx->compartment(), fun, parent)) return CloneFunctionReuseScript(cx, fun, parent, kind, newKind, proto); RootedScript script(cx, fun->getOrCreateScript(cx)); if (!script) return nullptr; RootedScope enclosingScope(cx, script->enclosingScope()); return CloneFunctionAndScript(cx, fun, parent, enclosingScope, kind, proto); } } /* namespace js */ #endif /* jsfuninlines_h */