// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_BASE_LOGGING_H_
#define V8_BASE_LOGGING_H_
#include <cstring>
#include <sstream>
#include <string>
#include "src/base/base-export.h"
#include "src/base/build_config.h"
#include "src/base/compiler-specific.h"
#include "src/base/template-utils.h"
[[noreturn]] PRINTF_FORMAT(3, 4) V8_BASE_EXPORT V8_NOINLINE
void V8_Fatal(const char* file, int line, const char* format, ...);
V8_BASE_EXPORT V8_NOINLINE void V8_Dcheck(const char* file, int line,
const char* message);
#ifdef DEBUG
#define FATAL(...) V8_Fatal(__FILE__, __LINE__, __VA_ARGS__)
#else
#define FATAL(...) V8_Fatal("", 0, __VA_ARGS__)
#endif
#define UNIMPLEMENTED() FATAL("unimplemented code")
#define UNREACHABLE() FATAL("unreachable code")
namespace v8 {
namespace base {
// Overwrite the default function that prints a stack trace.
V8_BASE_EXPORT void SetPrintStackTrace(void (*print_stack_trace_)());
// Override the default function that handles DCHECKs.
V8_BASE_EXPORT void SetDcheckFunction(void (*dcheck_Function)(const char*, int,
const char*));
// CHECK dies with a fatal error if condition is not true. It is *not*
// controlled by DEBUG, so the check will be executed regardless of
// compilation mode.
//
// We make sure CHECK et al. always evaluates their arguments, as
// doing CHECK(FunctionWithSideEffect()) is a common idiom.
#define CHECK_WITH_MSG(condition, message) \
do { \
if (V8_UNLIKELY(!(condition))) { \
FATAL("Check failed: %s.", message); \
} \
} while (0)
#define CHECK(condition) CHECK_WITH_MSG(condition, #condition)
#ifdef DEBUG
#define DCHECK_WITH_MSG(condition, message) \
do { \
if (V8_UNLIKELY(!(condition))) { \
V8_Dcheck(__FILE__, __LINE__, message); \
} \
} while (0)
#define DCHECK(condition) DCHECK_WITH_MSG(condition, #condition)
// Helper macro for binary operators.
// Don't use this macro directly in your code, use CHECK_EQ et al below.
#define CHECK_OP(name, op, lhs, rhs) \
do { \
if (std::string* _msg = ::v8::base::Check##name##Impl< \
typename ::v8::base::pass_value_or_ref<decltype(lhs)>::type, \
typename ::v8::base::pass_value_or_ref<decltype(rhs)>::type>( \
(lhs), (rhs), #lhs " " #op " " #rhs)) { \
FATAL("Check failed: %s.", _msg->c_str()); \
delete _msg; \
} \
} while (0)
#define DCHECK_OP(name, op, lhs, rhs) \
do { \
if (std::string* _msg = ::v8::base::Check##name##Impl< \
typename ::v8::base::pass_value_or_ref<decltype(lhs)>::type, \
typename ::v8::base::pass_value_or_ref<decltype(rhs)>::type>( \
(lhs), (rhs), #lhs " " #op " " #rhs)) { \
V8_Dcheck(__FILE__, __LINE__, _msg->c_str()); \
delete _msg; \
} \
} while (0)
#else
// Make all CHECK functions discard their log strings to reduce code
// bloat for official release builds.
#define CHECK_OP(name, op, lhs, rhs) \
do { \
bool _cmp = ::v8::base::Cmp##name##Impl< \
typename ::v8::base::pass_value_or_ref<decltype(lhs)>::type, \
typename ::v8::base::pass_value_or_ref<decltype(rhs)>::type>((lhs), \
(rhs)); \
CHECK_WITH_MSG(_cmp, #lhs " " #op " " #rhs); \
} while (0)
#define DCHECK_WITH_MSG(condition, msg) void(0);
#endif
// Define PrintCheckOperand<T> for each T which defines operator<< for ostream.
template <typename T>
typename std::enable_if<
!std::is_function<typename std::remove_pointer<T>::type>::value &&
has_output_operator<T>::value>::type
PrintCheckOperand(std::ostream& os, T val) {
os << std::forward<T>(val);
}
// Provide an overload for functions and function pointers. Function pointers
// don't implicitly convert to void* but do implicitly convert to bool, so
// without this function pointers are always printed as 1 or 0. (MSVC isn't
// standards-conforming here and converts function pointers to regular
// pointers, so this is a no-op for MSVC.)
template <typename T>
typename std::enable_if<
std::is_function<typename std::remove_pointer<T>::type>::value>::type
PrintCheckOperand(std::ostream& os, T val) {
os << reinterpret_cast<const void*>(val);
}
// Define PrintCheckOperand<T> for enums which have no operator<<.
template <typename T>
typename std::enable_if<std::is_enum<T>::value &&
!has_output_operator<T>::value>::type
PrintCheckOperand(std::ostream& os, T val) {
using underlying_t = typename std::underlying_type<T>::type;
// 8-bit types are not printed as number, so extend them to 16 bit.
using int_t = typename std::conditional<
std::is_same<underlying_t, uint8_t>::value, uint16_t,
typename std::conditional<std::is_same<underlying_t, int8_t>::value,
int16_t, underlying_t>::type>::type;
PrintCheckOperand(os, static_cast<int_t>(static_cast<underlying_t>(val)));
}
// Define default PrintCheckOperand<T> for non-printable types.
template <typename T>
typename std::enable_if<!has_output_operator<T>::value &&
!std::is_enum<T>::value>::type
PrintCheckOperand(std::ostream& os, T val) {
os << "<unprintable>";
}
// Define specializations for character types, defined in logging.cc.
#define DEFINE_PRINT_CHECK_OPERAND_CHAR(type) \
template <> \
V8_BASE_EXPORT void PrintCheckOperand<type>(std::ostream & os, type ch); \
template <> \
V8_BASE_EXPORT void PrintCheckOperand<type*>(std::ostream & os, \
type * cstr); \
template <> \
V8_BASE_EXPORT void PrintCheckOperand<const type*>(std::ostream & os, \
const type* cstr);
DEFINE_PRINT_CHECK_OPERAND_CHAR(char)
DEFINE_PRINT_CHECK_OPERAND_CHAR(signed char)
DEFINE_PRINT_CHECK_OPERAND_CHAR(unsigned char)
#undef DEFINE_PRINT_CHECK_OPERAND_CHAR
// Build the error message string. This is separate from the "Impl"
// function template because it is not performance critical and so can
// be out of line, while the "Impl" code should be inline. Caller
// takes ownership of the returned string.
template <typename Lhs, typename Rhs>
std::string* MakeCheckOpString(Lhs lhs, Rhs rhs, char const* msg) {
std::ostringstream ss;
ss << msg << " (";
PrintCheckOperand<Lhs>(ss, lhs);
ss << " vs. ";
PrintCheckOperand<Rhs>(ss, rhs);
ss << ")";
return new std::string(ss.str());
}
// Commonly used instantiations of MakeCheckOpString<>. Explicitly instantiated
// in logging.cc.
#define EXPLICIT_CHECK_OP_INSTANTIATION(type) \
extern template V8_BASE_EXPORT std::string* MakeCheckOpString<type, type>( \
type, type, char const*); \
extern template V8_BASE_EXPORT void PrintCheckOperand<type>(std::ostream&, \
type);
EXPLICIT_CHECK_OP_INSTANTIATION(int)
EXPLICIT_CHECK_OP_INSTANTIATION(long) // NOLINT(runtime/int)
EXPLICIT_CHECK_OP_INSTANTIATION(long long) // NOLINT(runtime/int)
EXPLICIT_CHECK_OP_INSTANTIATION(unsigned int)
EXPLICIT_CHECK_OP_INSTANTIATION(unsigned long) // NOLINT(runtime/int)
EXPLICIT_CHECK_OP_INSTANTIATION(unsigned long long) // NOLINT(runtime/int)
EXPLICIT_CHECK_OP_INSTANTIATION(void const*)
#undef EXPLICIT_CHECK_OP_INSTANTIATION
// comparison_underlying_type provides the underlying integral type of an enum,
// or std::decay<T>::type if T is not an enum. Booleans are converted to
// "unsigned int", to allow "unsigned int == bool" comparisons.
template <typename T>
struct comparison_underlying_type {
// std::underlying_type must only be used with enum types, thus use this
// {Dummy} type if the given type is not an enum.
enum Dummy {};
using decay = typename std::decay<T>::type;
static constexpr bool is_enum = std::is_enum<decay>::value;
using underlying = typename std::underlying_type<
typename std::conditional<is_enum, decay, Dummy>::type>::type;
using type_or_bool =
typename std::conditional<is_enum, underlying, decay>::type;
using type =
typename std::conditional<std::is_same<type_or_bool, bool>::value,
unsigned int, type_or_bool>::type;
};
// Cast a value to its underlying type
#define MAKE_UNDERLYING(Type, value) \
static_cast<typename comparison_underlying_type<Type>::type>(value)
// is_signed_vs_unsigned::value is true if both types are integral, Lhs is
// signed, and Rhs is unsigned. False in all other cases.
template <typename Lhs, typename Rhs>
struct is_signed_vs_unsigned {
using lhs_underlying = typename comparison_underlying_type<Lhs>::type;
using rhs_underlying = typename comparison_underlying_type<Rhs>::type;
static constexpr bool value = std::is_integral<lhs_underlying>::value &&
std::is_integral<rhs_underlying>::value &&
std::is_signed<lhs_underlying>::value &&
std::is_unsigned<rhs_underlying>::value;
};
// Same thing, other way around: Lhs is unsigned, Rhs signed.
template <typename Lhs, typename Rhs>
struct is_unsigned_vs_signed : public is_signed_vs_unsigned<Rhs, Lhs> {};
// Specialize the compare functions for signed vs. unsigned comparisons.
// std::enable_if ensures that this template is only instantiable if both Lhs
// and Rhs are integral types, and their signedness does not match.
#define MAKE_UNSIGNED(Type, value) \
static_cast<typename std::make_unsigned< \
typename comparison_underlying_type<Type>::type>::type>(value)
#define DEFINE_SIGNED_MISMATCH_COMP(CHECK, NAME, IMPL) \
template <typename Lhs, typename Rhs> \
V8_INLINE typename std::enable_if<CHECK<Lhs, Rhs>::value, bool>::type \
Cmp##NAME##Impl(Lhs lhs, Rhs rhs) { \
return IMPL; \
}
DEFINE_SIGNED_MISMATCH_COMP(is_signed_vs_unsigned, EQ,
lhs >= 0 && MAKE_UNSIGNED(Lhs, lhs) ==
MAKE_UNDERLYING(Rhs, rhs))
DEFINE_SIGNED_MISMATCH_COMP(is_signed_vs_unsigned, LT,
lhs < 0 || MAKE_UNSIGNED(Lhs, lhs) <
MAKE_UNDERLYING(Rhs, rhs))
DEFINE_SIGNED_MISMATCH_COMP(is_signed_vs_unsigned, LE,
lhs <= 0 || MAKE_UNSIGNED(Lhs, lhs) <=
MAKE_UNDERLYING(Rhs, rhs))
DEFINE_SIGNED_MISMATCH_COMP(is_signed_vs_unsigned, NE, !CmpEQImpl(lhs, rhs))
DEFINE_SIGNED_MISMATCH_COMP(is_signed_vs_unsigned, GT, !CmpLEImpl(lhs, rhs))
DEFINE_SIGNED_MISMATCH_COMP(is_signed_vs_unsigned, GE, !CmpLTImpl(lhs, rhs))
DEFINE_SIGNED_MISMATCH_COMP(is_unsigned_vs_signed, EQ, CmpEQImpl(rhs, lhs))
DEFINE_SIGNED_MISMATCH_COMP(is_unsigned_vs_signed, NE, CmpNEImpl(rhs, lhs))
DEFINE_SIGNED_MISMATCH_COMP(is_unsigned_vs_signed, LT, CmpGTImpl(rhs, lhs))
DEFINE_SIGNED_MISMATCH_COMP(is_unsigned_vs_signed, LE, CmpGEImpl(rhs, lhs))
DEFINE_SIGNED_MISMATCH_COMP(is_unsigned_vs_signed, GT, CmpLTImpl(rhs, lhs))
DEFINE_SIGNED_MISMATCH_COMP(is_unsigned_vs_signed, GE, CmpLEImpl(rhs, lhs))
#undef MAKE_UNSIGNED
#undef DEFINE_SIGNED_MISMATCH_COMP
// Helper functions for CHECK_OP macro.
// The (float, float) and (double, double) instantiations are explicitly
// externalized to ensure proper 32/64-bit comparisons on x86.
// The Cmp##NAME##Impl function is only instantiable if one of the two types is
// not integral or their signedness matches (i.e. whenever no specialization is
// required, see above). Otherwise it is disabled by the enable_if construct,
// and the compiler will pick a specialization from above.
#define DEFINE_CHECK_OP_IMPL(NAME, op) \
template <typename Lhs, typename Rhs> \
V8_INLINE \
typename std::enable_if<!is_signed_vs_unsigned<Lhs, Rhs>::value && \
!is_unsigned_vs_signed<Lhs, Rhs>::value, \
bool>::type Cmp##NAME##Impl(Lhs lhs, Rhs rhs) { \
return lhs op rhs; \
} \
template <typename Lhs, typename Rhs> \
V8_INLINE std::string* Check##NAME##Impl(Lhs lhs, Rhs rhs, \
char const* msg) { \
using LhsPassT = typename pass_value_or_ref<Lhs>::type; \
using RhsPassT = typename pass_value_or_ref<Rhs>::type; \
bool cmp = Cmp##NAME##Impl<LhsPassT, RhsPassT>(lhs, rhs); \
return V8_LIKELY(cmp) \
? nullptr \
: MakeCheckOpString<LhsPassT, RhsPassT>(lhs, rhs, msg); \
} \
extern template V8_BASE_EXPORT std::string* Check##NAME##Impl<float, float>( \
float lhs, float rhs, char const* msg); \
extern template V8_BASE_EXPORT std::string* \
Check##NAME##Impl<double, double>(double lhs, double rhs, \
char const* msg);
DEFINE_CHECK_OP_IMPL(EQ, ==)
DEFINE_CHECK_OP_IMPL(NE, !=)
DEFINE_CHECK_OP_IMPL(LE, <=)
DEFINE_CHECK_OP_IMPL(LT, < )
DEFINE_CHECK_OP_IMPL(GE, >=)
DEFINE_CHECK_OP_IMPL(GT, > )
#undef DEFINE_CHECK_OP_IMPL
#define CHECK_EQ(lhs, rhs) CHECK_OP(EQ, ==, lhs, rhs)
#define CHECK_NE(lhs, rhs) CHECK_OP(NE, !=, lhs, rhs)
#define CHECK_LE(lhs, rhs) CHECK_OP(LE, <=, lhs, rhs)
#define CHECK_LT(lhs, rhs) CHECK_OP(LT, <, lhs, rhs)
#define CHECK_GE(lhs, rhs) CHECK_OP(GE, >=, lhs, rhs)
#define CHECK_GT(lhs, rhs) CHECK_OP(GT, >, lhs, rhs)
#define CHECK_NULL(val) CHECK((val) == nullptr)
#define CHECK_NOT_NULL(val) CHECK((val) != nullptr)
#define CHECK_IMPLIES(lhs, rhs) \
CHECK_WITH_MSG(!(lhs) || (rhs), #lhs " implies " #rhs)
} // namespace base
} // namespace v8
// The DCHECK macro is equivalent to CHECK except that it only
// generates code in debug builds.
#ifdef DEBUG
#define DCHECK_EQ(lhs, rhs) DCHECK_OP(EQ, ==, lhs, rhs)
#define DCHECK_NE(lhs, rhs) DCHECK_OP(NE, !=, lhs, rhs)
#define DCHECK_GT(lhs, rhs) DCHECK_OP(GT, >, lhs, rhs)
#define DCHECK_GE(lhs, rhs) DCHECK_OP(GE, >=, lhs, rhs)
#define DCHECK_LT(lhs, rhs) DCHECK_OP(LT, <, lhs, rhs)
#define DCHECK_LE(lhs, rhs) DCHECK_OP(LE, <=, lhs, rhs)
#define DCHECK_NULL(val) DCHECK((val) == nullptr)
#define DCHECK_NOT_NULL(val) DCHECK((val) != nullptr)
#define DCHECK_IMPLIES(lhs, rhs) \
DCHECK_WITH_MSG(!(lhs) || (rhs), #lhs " implies " #rhs)
#else
#define DCHECK(condition) ((void) 0)
#define DCHECK_EQ(v1, v2) ((void) 0)
#define DCHECK_NE(v1, v2) ((void) 0)
#define DCHECK_GT(v1, v2) ((void) 0)
#define DCHECK_GE(v1, v2) ((void) 0)
#define DCHECK_LT(v1, v2) ((void) 0)
#define DCHECK_LE(v1, v2) ((void) 0)
#define DCHECK_NULL(val) ((void) 0)
#define DCHECK_NOT_NULL(val) ((void) 0)
#define DCHECK_IMPLIES(v1, v2) ((void) 0)
#endif
#endif // V8_BASE_LOGGING_H_