blob: f958cc12f8f3b01db9bb1d2005b2ec64d2f289fa [file] [log] [blame]
// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <stddef.h>
#include <stdint.h>
// COURGETTE_HISTOGRAM_TARGETS prints out a histogram of how frequently
// different target addresses are referenced. Purely for debugging.
namespace courgette {
typedef uint32_t RVA;
const RVA kUnassignedRVA = 0xFFFFFFFFU;
// A Label is a symbolic reference to an address. Unlike a conventional
// assembly language, we always know the address. The address will later be
// stored in a table and the Label will be replaced with the index into the
// table.
// TODO(huangs): Make this a struct, and remove "_" from member names.
class Label {
enum : int { kNoIndex = -1 };
explicit Label(RVA rva) : rva_(rva) {}
Label(RVA rva, int index) : rva_(rva), index_(index) {}
Label(RVA rva, int index, int32_t count)
: rva_(rva), index_(index), count_(count) {}
bool operator==(const Label& other) const {
return rva_ == other.rva_ && index_ == other.index_ &&
count_ == other.count_;
RVA rva_ = kUnassignedRVA; // Address referred to by the label.
int index_ = kNoIndex; // Index of address in address table.
int32_t count_ = 0;
// These helper functions avoid the need for casts in the main code.
inline uint16_t ReadU16(const uint8_t* address, size_t offset) {
return *reinterpret_cast<const uint16_t*>(address + offset);
inline uint32_t ReadU32(const uint8_t* address, size_t offset) {
return *reinterpret_cast<const uint32_t*>(address + offset);
inline uint64_t ReadU64(const uint8_t* address, size_t offset) {
return *reinterpret_cast<const uint64_t*>(address + offset);
inline uint16_t Read16LittleEndian(const void* address) {
return *reinterpret_cast<const uint16_t*>(address);
inline uint32_t Read32LittleEndian(const void* address) {
return *reinterpret_cast<const uint32_t*>(address);
inline uint64_t Read64LittleEndian(const void* address) {
return *reinterpret_cast<const uint64_t*>(address);
} // namespace courgette