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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/. */
#include "frontend/TDZCheckCache.h"
#include "frontend/BytecodeEmitter.h"
using namespace js;
using namespace js::frontend;
using mozilla::Maybe;
using mozilla::Nothing;
using mozilla::Some;
TDZCheckCache::TDZCheckCache(BytecodeEmitter* bce)
: Nestable<TDZCheckCache>(&bce->innermostTDZCheckCache),
cache_(bce->fc->nameCollectionPool()) {}
bool TDZCheckCache::ensureCache(BytecodeEmitter* bce) {
return cache_ || cache_.acquire(bce->fc);
}
Maybe<MaybeCheckTDZ> TDZCheckCache::needsTDZCheck(BytecodeEmitter* bce,
TaggedParserAtomIndex name) {
if (!ensureCache(bce)) {
return Nothing();
}
CheckTDZMap::AddPtr p = cache_->lookupForAdd(name);
if (p) {
return Some(p->value().wrapped);
}
MaybeCheckTDZ rv = CheckTDZ;
for (TDZCheckCache* it = enclosing(); it; it = it->enclosing()) {
if (it->cache_) {
if (CheckTDZMap::Ptr p2 = it->cache_->lookup(name)) {
rv = p2->value();
break;
}
}
}
if (!cache_->add(p, name, rv)) {
ReportOutOfMemory(bce->fc);
return Nothing();
}
return Some(rv);
}
bool TDZCheckCache::noteTDZCheck(BytecodeEmitter* bce,
TaggedParserAtomIndex name,
MaybeCheckTDZ check) {
if (!ensureCache(bce)) {
return false;
}
CheckTDZMap::AddPtr p = cache_->lookupForAdd(name);
if (p) {
MOZ_ASSERT(
!check,
"TDZ only needs to be checked once per binding per basic block.");
p->value() = check;
} else {
if (!cache_->add(p, name, check)) {
ReportOutOfMemory(bce->fc);
return false;
}
}
return true;
}