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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,
#include "mozilla/Casting.h"
#include "mozilla/ThreadSafety.h"
#include <stdint.h>
#include <cstdint>
#include <limits>
#include <type_traits>
#include <iostream>
#include <tuple>
#include <type_traits>
using mozilla::AssertedCast;
using mozilla::BitwiseCast;
using mozilla::SaturatingCast;
using mozilla::detail::IsInBounds;
static const uint8_t floatMantissaBitsPlusOne = 24;
static const uint8_t doubleMantissaBitsPlusOne = 53;
template <typename Uint, typename Ulong, bool = (sizeof(Uint) == sizeof(Ulong))>
struct UintUlongBitwiseCast;
template <typename Uint, typename Ulong>
struct UintUlongBitwiseCast<Uint, Ulong, true> {
static void test() {
MOZ_RELEASE_ASSERT(BitwiseCast<Ulong>(Uint(8675309)) == Ulong(8675309));
}
};
template <typename Uint, typename Ulong>
struct UintUlongBitwiseCast<Uint, Ulong, false> {
static void test() {}
};
static void TestBitwiseCast() {
MOZ_RELEASE_ASSERT(BitwiseCast<int>(int(8675309)) == int(8675309));
UintUlongBitwiseCast<unsigned int, unsigned long>::test();
}
static void TestSameSize() {
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int16_t>(int16_t(0))));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int16_t>(int16_t(INT16_MIN))));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int16_t>(int16_t(INT16_MAX))));
MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, uint16_t>(uint16_t(UINT16_MAX))));
MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, int16_t>(uint16_t(0))));
MOZ_RELEASE_ASSERT((!IsInBounds<uint16_t, int16_t>(uint16_t(-1))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint16_t>(int16_t(-1))));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, uint16_t>(int16_t(INT16_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint16_t>(int16_t(INT16_MIN))));
MOZ_RELEASE_ASSERT((IsInBounds<int32_t, uint32_t>(int32_t(INT32_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, uint32_t>(int32_t(INT32_MIN))));
}
static void TestToBiggerSize() {
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int32_t>(int16_t(0))));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int32_t>(int16_t(INT16_MIN))));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int32_t>(int16_t(INT16_MAX))));
MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, uint32_t>(uint16_t(UINT16_MAX))));
MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, int32_t>(uint16_t(0))));
MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, int32_t>(uint16_t(-1))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint32_t>(int16_t(-1))));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, uint32_t>(int16_t(INT16_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint32_t>(int16_t(INT16_MIN))));
MOZ_RELEASE_ASSERT((IsInBounds<int32_t, uint64_t>(int32_t(INT32_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, uint64_t>(int32_t(INT32_MIN))));
}
static void TestToSmallerSize() {
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int8_t>(int16_t(0))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, int8_t>(int16_t(INT16_MIN))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, int8_t>(int16_t(INT16_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<uint16_t, uint8_t>(uint16_t(UINT16_MAX))));
MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, int8_t>(uint16_t(0))));
MOZ_RELEASE_ASSERT((!IsInBounds<uint16_t, int8_t>(uint16_t(-1))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint8_t>(int16_t(-1))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint8_t>(int16_t(INT16_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint8_t>(int16_t(INT16_MIN))));
MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, uint16_t>(int32_t(INT32_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, uint16_t>(int32_t(INT32_MIN))));
// Boundary cases
MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, int32_t>(int64_t(INT32_MIN) - 1)));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, int32_t>(int64_t(INT32_MIN))));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, int32_t>(int64_t(INT32_MIN) + 1)));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, int32_t>(int64_t(INT32_MAX) - 1)));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, int32_t>(int64_t(INT32_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, int32_t>(int64_t(INT32_MAX) + 1)));
MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, uint32_t>(int64_t(-1))));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, uint32_t>(int64_t(0))));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, uint32_t>(int64_t(1))));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, uint32_t>(int64_t(UINT32_MAX) - 1)));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, uint32_t>(int64_t(UINT32_MAX))));
MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, uint32_t>(int64_t(UINT32_MAX) + 1)));
}
template <typename In, typename Out>
void checkBoundariesFloating(In aEpsilon = {}, Out aIntegerOffset = {}) {
// Check the max value of the input float can't be represented as an integer.
// This is true for all floating point and integer width.
MOZ_RELEASE_ASSERT((!IsInBounds<In, Out>(std::numeric_limits<In>::max())));
// Check that the max value of the integer, as a float, minus an offset that
// depends on the magnitude, can be represented as an integer.
MOZ_RELEASE_ASSERT((IsInBounds<In, Out>(
static_cast<In>(std::numeric_limits<Out>::max() - aIntegerOffset))));
// Check that the max value of the integer, plus a number that depends on the
// magnitude of the number, can't be represented as this integer (because it
// becomes too big).
MOZ_RELEASE_ASSERT((!IsInBounds<In, Out>(
aEpsilon + static_cast<In>(std::numeric_limits<Out>::max()))));
if constexpr (std::is_signed_v<In>) {
// Same for negative numbers.
MOZ_RELEASE_ASSERT(
(!IsInBounds<In, Out>(std::numeric_limits<In>::lowest())));
MOZ_RELEASE_ASSERT((IsInBounds<In, Out>(
static_cast<In>(std::numeric_limits<Out>::lowest()))));
MOZ_RELEASE_ASSERT((!IsInBounds<In, Out>(
static_cast<In>(std::numeric_limits<Out>::lowest()) - aEpsilon)));
} else {
// Check for negative floats and unsigned integer types.
MOZ_RELEASE_ASSERT((!IsInBounds<In, Out>(static_cast<In>(-1))));
}
}
void TestFloatConversion() {
MOZ_RELEASE_ASSERT((!IsInBounds<uint64_t, float>(UINT64_MAX)));
MOZ_RELEASE_ASSERT((!IsInBounds<uint32_t, float>(UINT32_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, float>(UINT16_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<uint8_t, float>(UINT8_MAX)));
MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, float>(INT64_MAX)));
MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, float>(INT64_MIN)));
MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, float>(INT32_MAX)));
MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, float>(INT32_MIN)));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, float>(INT16_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, float>(INT16_MIN)));
MOZ_RELEASE_ASSERT((IsInBounds<int8_t, float>(INT8_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<int8_t, float>(INT8_MIN)));
MOZ_RELEASE_ASSERT((!IsInBounds<uint64_t, double>(UINT64_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<uint32_t, double>(UINT32_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, double>(UINT16_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<uint8_t, double>(UINT8_MAX)));
MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, double>(INT64_MAX)));
MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, double>(INT64_MIN)));
MOZ_RELEASE_ASSERT((IsInBounds<int32_t, double>(INT32_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<int32_t, double>(INT32_MIN)));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, double>(INT16_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<int16_t, double>(INT16_MIN)));
MOZ_RELEASE_ASSERT((IsInBounds<int8_t, double>(INT8_MAX)));
MOZ_RELEASE_ASSERT((IsInBounds<int8_t, double>(INT8_MIN)));
// Floor check
MOZ_RELEASE_ASSERT((IsInBounds<float, uint64_t>(4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<uint64_t>(4.3f) == 4u));
MOZ_RELEASE_ASSERT((IsInBounds<float, uint32_t>(4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<uint32_t>(4.3f) == 4u));
MOZ_RELEASE_ASSERT((IsInBounds<float, uint16_t>(4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<uint16_t>(4.3f) == 4u));
MOZ_RELEASE_ASSERT((IsInBounds<float, uint8_t>(4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<uint8_t>(4.3f) == 4u));
MOZ_RELEASE_ASSERT((IsInBounds<float, int64_t>(4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<int64_t>(4.3f) == 4u));
MOZ_RELEASE_ASSERT((IsInBounds<float, int32_t>(4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<int32_t>(4.3f) == 4u));
MOZ_RELEASE_ASSERT((IsInBounds<float, int16_t>(4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<int16_t>(4.3f) == 4u));
MOZ_RELEASE_ASSERT((IsInBounds<float, int8_t>(4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<int8_t>(4.3f) == 4u));
MOZ_RELEASE_ASSERT((IsInBounds<float, int64_t>(-4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<int64_t>(-4.3f) == -4));
MOZ_RELEASE_ASSERT((IsInBounds<float, int32_t>(-4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<int32_t>(-4.3f) == -4));
MOZ_RELEASE_ASSERT((IsInBounds<float, int16_t>(-4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<int16_t>(-4.3f) == -4));
MOZ_RELEASE_ASSERT((IsInBounds<float, int8_t>(-4.3)));
MOZ_RELEASE_ASSERT((AssertedCast<int8_t>(-4.3f) == -4));
// Bound check for float to unsigned integer conversion. The parameters are
// espilons and offsets allowing to check boundaries, that depend on the
// magnitude of the numbers.
checkBoundariesFloating<double, uint64_t>(2049.);
checkBoundariesFloating<double, uint32_t>(1.);
checkBoundariesFloating<double, uint16_t>(1.);
checkBoundariesFloating<double, uint8_t>(1.);
// Large number because of the lack of precision of floats at this magnitude
checkBoundariesFloating<float, uint64_t>(1.1e12f);
checkBoundariesFloating<float, uint32_t>(1.f, 128u);
checkBoundariesFloating<float, uint16_t>(1.f);
checkBoundariesFloating<float, uint8_t>(1.f);
checkBoundariesFloating<double, int64_t>(1025.);
checkBoundariesFloating<double, int32_t>(1.);
checkBoundariesFloating<double, int16_t>(1.);
checkBoundariesFloating<double, int8_t>(1.);
// Large number because of the lack of precision of floats at this magnitude
checkBoundariesFloating<float, int64_t>(1.1e12f);
checkBoundariesFloating<float, int32_t>(256.f, 64u);
checkBoundariesFloating<float, int16_t>(1.f);
checkBoundariesFloating<float, int8_t>(1.f);
// Integer to floating point, boundary cases
MOZ_RELEASE_ASSERT(!(IsInBounds<int64_t, float>(
int64_t(std::pow(2, floatMantissaBitsPlusOne)) + 1)));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, float>(
int64_t(std::pow(2, floatMantissaBitsPlusOne)))));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, float>(
int64_t(std::pow(2, floatMantissaBitsPlusOne)) - 1)));
MOZ_RELEASE_ASSERT(!(IsInBounds<int64_t, float>(
int64_t(-std::pow(2, floatMantissaBitsPlusOne)) - 1)));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, float>(
int64_t(-std::pow(2, floatMantissaBitsPlusOne)))));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, float>(
int64_t(-std::pow(2, floatMantissaBitsPlusOne)) + 1)));
MOZ_RELEASE_ASSERT(!(IsInBounds<int64_t, double>(
uint64_t(std::pow(2, doubleMantissaBitsPlusOne)) + 1)));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, double>(
uint64_t(std::pow(2, doubleMantissaBitsPlusOne)))));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, double>(
uint64_t(std::pow(2, doubleMantissaBitsPlusOne)) - 1)));
MOZ_RELEASE_ASSERT(!(IsInBounds<int64_t, double>(
int64_t(-std::pow(2, doubleMantissaBitsPlusOne)) - 1)));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, double>(
int64_t(-std::pow(2, doubleMantissaBitsPlusOne)))));
MOZ_RELEASE_ASSERT((IsInBounds<int64_t, double>(
int64_t(-std::pow(2, doubleMantissaBitsPlusOne)) + 1)));
MOZ_RELEASE_ASSERT(!(IsInBounds<uint64_t, double>(UINT64_MAX)));
MOZ_RELEASE_ASSERT(!(IsInBounds<int64_t, double>(INT64_MAX)));
MOZ_RELEASE_ASSERT(!(IsInBounds<int64_t, double>(INT64_MIN)));
MOZ_RELEASE_ASSERT(
!(IsInBounds<double, float>(std::numeric_limits<double>::max())));
MOZ_RELEASE_ASSERT(
!(IsInBounds<double, float>(-std::numeric_limits<double>::max())));
}
#define ASSERT_EQ(a, b) \
if ((a) != (b)) { \
std::cerr << __FILE__ << ":" << __LINE__ << " Actual: " << +(a) << ", " \
<< "expected: " << +(b) << std::endl; \
MOZ_CRASH(); \
}
#ifdef ENABLE_DEBUG_PRINT
# define DEBUG_PRINT(in, out) \
std::cout << "\tIn: " << +in << ", " << "out: " << +out << std::endl;
#else
# define DEBUG_PRINT(in, out)
#endif
template <typename In, typename Out>
void TestTypePairImpl() {
std::cout << __PRETTY_FUNCTION__ << std::endl;
std::cout << std::fixed;
// Test casting infinities to integer works
if constexpr (std::is_floating_point_v<In> &&
!std::is_floating_point_v<Out>) {
Out v = SaturatingCast<Out>(std::numeric_limits<In>::infinity());
ASSERT_EQ(v, std::numeric_limits<Out>::max());
v = SaturatingCast<Out>(-std::numeric_limits<In>::infinity());
ASSERT_EQ(v, std::numeric_limits<Out>::lowest());
}
// Saturation of a floating point value that is infinity is infinity
if constexpr (std::is_floating_point_v<Out> && std::is_floating_point_v<In>) {
In in = std::numeric_limits<In>::infinity();
Out v = SaturatingCast<Out>(in);
DEBUG_PRINT(in, v);
ASSERT_EQ(v, std::numeric_limits<Out>::infinity());
in = -std::numeric_limits<In>::infinity();
v = SaturatingCast<In>(in);
DEBUG_PRINT(in, v);
ASSERT_EQ(v, -std::numeric_limits<Out>::infinity());
return;
} else {
if constexpr (sizeof(In) > sizeof(Out) && std::is_integral_v<Out>) {
// Test with a value just outside the range of the output type
In in = static_cast<In>(std::numeric_limits<Out>::max()) + 1ull;
Out v = SaturatingCast<Out>(in);
DEBUG_PRINT(in, v);
ASSERT_EQ(v, std::numeric_limits<Out>::max());
if (std::is_signed_v<In>) {
// Test with a value just below the range of the output type
Out lowest = std::numeric_limits<Out>::lowest();
in = static_cast<In>(lowest) - 1;
v = SaturatingCast<Out>(in);
DEBUG_PRINT(in, v);
if constexpr (std::is_signed_v<In> && !std::is_signed_v<Out>) {
ASSERT_EQ(v, 0);
} else {
ASSERT_EQ(v, std::numeric_limits<Out>::lowest());
}
}
} else if constexpr (std::is_integral_v<In> && std::is_integral_v<Out> &&
sizeof(In) == sizeof(Out) && !std::is_signed_v<In> &&
std::is_signed_v<Out>) {
// Test that max uintXX_t saturates to max intXX_t
In in = static_cast<In>(std::numeric_limits<Out>::max()) + 1;
Out v = SaturatingCast<Out>(in);
DEBUG_PRINT(in, v);
ASSERT_EQ(v, std::numeric_limits<Out>::max());
}
// SaturatingCast of zero is zero
In in = static_cast<In>(0);
Out v = SaturatingCast<Out>(in);
DEBUG_PRINT(in, v);
ASSERT_EQ(v, 0);
if constexpr (sizeof(In) >= sizeof(Out) && std::is_signed_v<Out> &&
std::is_signed_v<In>) {
// Test with a value within the range of the output type
In in = static_cast<In>(std::numeric_limits<Out>::max() / 2);
Out v = SaturatingCast<Out>(in);
DEBUG_PRINT(in, v);
ASSERT_EQ(v, in);
// Test with a negative value within the range of the output type
in = static_cast<In>(std::numeric_limits<Out>::lowest() / 2);
v = SaturatingCast<Out>(in);
DEBUG_PRINT(in, v);
ASSERT_EQ(v, in);
}
}
}
template <typename In, typename Out>
void TestTypePair() {
constexpr bool fromFloat = std::is_floating_point_v<In>;
constexpr bool toFloat = std::is_floating_point_v<Out>;
// Don't test casting to the same type
if constexpr (!std::is_same_v<In, Out>) {
if constexpr ((fromFloat && !toFloat) || (!fromFloat && !toFloat)) {
TestTypePairImpl<In, Out>();
}
}
}
template <typename T, typename... Ts>
void for_each_type_pair(std::tuple<T, Ts...>) {
(TestTypePair<T, Ts>(), ...);
(TestTypePair<Ts, T>(), ...);
if constexpr (sizeof...(Ts) > 1) {
for_each_type_pair(std::tuple<Ts...>{});
}
}
template <typename... Args>
void TestSaturatingCastImpl() {
for_each_type_pair(std::tuple<Args...>{});
}
template <typename T, typename... Ts>
void TestFirstToOthers() {
(TestTypePair<T, Ts>(), ...);
}
void TestSaturatingCast() {
// Each integer type against every other
TestSaturatingCastImpl<short, int, long, int8_t, uint8_t, int16_t, uint16_t,
int32_t, uint32_t, int64_t, uint64_t>();
// Floating point types to every integer type
TestFirstToOthers<float, short, int, long, int8_t, uint8_t, int16_t, uint16_t,
int32_t, uint32_t, int64_t, uint64_t>();
TestFirstToOthers<double, short, int, long, int8_t, uint8_t, int16_t,
uint16_t, int32_t, uint32_t, int64_t, uint64_t>();
}
int main() {
TestBitwiseCast();
TestSameSize();
TestToBiggerSize();
TestToSmallerSize();
TestFloatConversion();
TestSaturatingCast();
return 0;
}