/* -*- 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 "js/ProfilingStack.h"
#include "mozilla/IntegerRange.h"
#include "mozilla/MathAlgorithms.h"
#include <algorithm>
using namespace js;
ProfilingStack::~ProfilingStack() {
// The label macros keep a reference to the ProfilingStack to avoid a TLS
// access. If these are somehow not all cleared we will get a
// use-after-free so better to crash now.
MOZ_RELEASE_ASSERT(stackPointer == 0);
delete[] frames;
}
void ProfilingStack::ensureCapacitySlow() {
MOZ_ASSERT(stackPointer >= capacity);
const uint32_t kInitialCapacity = 4096 /
sizeof(ProfilingStackFrame);
uint32_t sp = stackPointer;
uint32_t newCapacity;
if (!capacity) {
newCapacity = kInitialCapacity;
}
else {
size_t memoryGoal =
mozilla::RoundUpPow2(capacity * 2 *
sizeof(ProfilingStackFrame));
newCapacity = memoryGoal /
sizeof(ProfilingStackFrame);
}
newCapacity = std::max(sp + 1, newCapacity);
auto* newFrames =
new js::ProfilingStackFrame[newCapacity];
// It's important that `frames` / `capacity` / `stackPointer` remain
// consistent here at all times.
for (
auto i : mozilla::IntegerRange(capacity)) {
newFrames[i] = frames[i];
}
js::ProfilingStackFrame* oldFrames = frames;
frames = newFrames;
capacity = newCapacity;
delete[] oldFrames;
}
