chromium/base/trace_event/heap_profiler_allocation_context.h

// Copyright 2015 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef BASE_TRACE_EVENT_HEAP_PROFILER_ALLOCATION_CONTEXT_H_
#define BASE_TRACE_EVENT_HEAP_PROFILER_ALLOCATION_CONTEXT_H_

#include <stddef.h>
#include <stdint.h>

#include <functional>

#include "base/base_export.h"
#include "base/memory/raw_ptr.h"

namespace base {
namespace trace_event {

// When heap profiling is enabled, tracing keeps track of the allocation
// context for each allocation intercepted. It is generated by the
// |AllocationContextTracker| which keeps stacks of context in TLS.
// The tracker is initialized lazily.

// The backtrace in the allocation context is a snapshot of the native call
// stack.

// Represents a stack frame. Used in Backtrace class below.
//
// Conceptually stack frame is identified by its value, and type is used
// mostly to properly format the value. Value is expected to be a valid
// pointer from process' address space.
struct BASE_EXPORT StackFrame { … };

bool BASE_EXPORT operator < (const StackFrame& lhs, const StackFrame& rhs);
bool BASE_EXPORT operator == (const StackFrame& lhs, const StackFrame& rhs);
bool BASE_EXPORT operator != (const StackFrame& lhs, const StackFrame& rhs);

struct BASE_EXPORT Backtrace { … };

bool BASE_EXPORT operator==(const Backtrace& lhs, const Backtrace& rhs);
bool BASE_EXPORT operator!=(const Backtrace& lhs, const Backtrace& rhs);

// The |AllocationContext| is context metadata that is kept for every allocation
// when heap profiling is enabled. To simplify memory management for book-
// keeping, this struct has a fixed size.
struct BASE_EXPORT AllocationContext { … };

bool BASE_EXPORT operator==(const AllocationContext& lhs,
                            const AllocationContext& rhs);
bool BASE_EXPORT operator!=(const AllocationContext& lhs,
                            const AllocationContext& rhs);

// Struct to store the size and count of the allocations.
struct AllocationMetrics { … };

}  // namespace trace_event
}  // namespace base

namespace std {

template <>
struct BASE_EXPORT hash<base::trace_event::StackFrame> { … };

template <>
struct BASE_EXPORT hash<base::trace_event::Backtrace> { … };

template <>
struct BASE_EXPORT hash<base::trace_event::AllocationContext> { … };

}  // namespace std

#endif  // BASE_TRACE_EVENT_HEAP_PROFILER_ALLOCATION_CONTEXT_H_