src/third_party/mozjs-45/js/src/frontend/ParseMaps.cpp

/* -*- 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/. */

#include "frontend/ParseMaps-inl.h"

#include "jscntxt.h"

#include "frontend/FullParseHandler.h"
#include "frontend/SyntaxParseHandler.h"

using namespace js;
using namespace js::frontend;

void
ParseMapPool::checkInvariants()
{
    /*
     * Having all values be of the same size permits us to easily reuse the
     * allocated space for each of the map types.
     */
    JS_STATIC_ASSERT(sizeof(Definition*) == sizeof(jsatomid));
    JS_STATIC_ASSERT(sizeof(Definition*) == sizeof(DefinitionList));
    JS_STATIC_ASSERT(sizeof(AtomDefnMap::Entry) == sizeof(AtomIndexMap::Entry));
    JS_STATIC_ASSERT(sizeof(AtomDefnMap::Entry) == sizeof(AtomDefnListMap::Entry));
    JS_STATIC_ASSERT(sizeof(AtomMapT::Entry) == sizeof(AtomDefnListMap::Entry));
    /* Ensure that the HasTable::clear goes quickly via memset. */
    JS_STATIC_ASSERT(mozilla::IsPod<AtomIndexMap::WordMap::Entry>::value);
    JS_STATIC_ASSERT(mozilla::IsPod<AtomDefnListMap::WordMap::Entry>::value);
    JS_STATIC_ASSERT(mozilla::IsPod<AtomDefnMap::WordMap::Entry>::value);
}

void
ParseMapPool::purgeAll()
{
    void** end = all.end();
    for (void** it = all.begin(); it != end; ++it)
        js_delete<AtomMapT>(asAtomMap(*it));

    all.clearAndFree();
    recyclable.clearAndFree();
}

void*
ParseMapPool::allocateFresh()
{
    size_t newAllLength = all.length() + 1;
    if (!all.reserve(newAllLength) || !recyclable.reserve(newAllLength))
        return nullptr;

    AtomMapT* map = js_new<AtomMapT>();
    if (!map)
        return nullptr;

    all.infallibleAppend(map);
    return (void*) map;
}

DefinitionList::Node*
DefinitionList::allocNode(ExclusiveContext* cx, LifoAlloc& alloc, uintptr_t head, Node* tail)
{
    Node* result = alloc.new_<Node>(head, tail);
    if (!result)
        ReportOutOfMemory(cx);
    return result;
}

#ifdef DEBUG
template <typename ParseHandler>
void
AtomDecls<ParseHandler>::dump()
{
    for (AtomDefnListRange r = map->all(); !r.empty(); r.popFront()) {
        fprintf(stderr, "atom: ");
        DumpAtom(r.front().key());
        const DefinitionList& dlist = r.front().value();
        for (DefinitionList::Range dr = dlist.all(); !dr.empty(); dr.popFront()) {
            fprintf(stderr, "    defn: %p\n", (void*) dr.front<ParseHandler>());
        }
    }
}

void
DumpAtomDefnMap(const AtomDefnMapPtr& map)
{
    if (map->empty()) {
        fprintf(stderr, "empty\n");
        return;
    }

    for (AtomDefnRange r = map->all(); !r.empty(); r.popFront()) {
        fprintf(stderr, "atom: ");
        DumpAtom(r.front().key());
        fprintf(stderr, "defn: %p\n", (void*) r.front().value().get<FullParseHandler>());
    }
}
#endif

template <typename ParseHandler>
bool
AtomDecls<ParseHandler>::addShadow(JSAtom* atom, typename ParseHandler::DefinitionNode defn)
{
    AtomDefnListAddPtr p = map->lookupForAdd(atom);
    if (!p)
        return map->add(p, atom, DefinitionList(ParseHandler::definitionToBits(defn)));

    return p.value().pushFront<ParseHandler>(cx, alloc, defn);
}

void
frontend::InitAtomMap(frontend::AtomIndexMap* indices, HeapPtrAtom* atoms)
{
    if (indices->isMap()) {
        typedef AtomIndexMap::WordMap WordMap;
        const WordMap& wm = indices->asMap();
        for (WordMap::Range r = wm.all(); !r.empty(); r.popFront()) {
            JSAtom* atom = r.front().key();
            jsatomid index = r.front().value();
            MOZ_ASSERT(index < indices->count());
            atoms[index].init(atom);
        }
    } else {
        const AtomIndexMap::InlineElem* end = indices->inlineEnd();
        for (const AtomIndexMap::InlineElem* it = indices->asInline(); it != end; ++it) {
            JSAtom* atom = it->key;
            if (!atom)
                continue;
            MOZ_ASSERT(it->value < indices->count());
            atoms[it->value].init(atom);
        }
    }
}

template class js::frontend::AtomDecls<FullParseHandler>;
template class js::frontend::AtomDecls<SyntaxParseHandler>;