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//===-- Properties of floating point numbers --------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIBC_UTILS_FPUTIL_FLOAT_PROPERTIES_H
#define LLVM_LIBC_UTILS_FPUTIL_FLOAT_PROPERTIES_H
#include <stdint.h>
namespace __llvm_libc {
namespace fputil {
template <typename T> struct FloatProperties {};
template <> struct FloatProperties<float> {
typedef uint32_t BitsType;
static_assert(sizeof(BitsType) == sizeof(float),
"Unexpected size of 'float' type.");
static constexpr uint32_t bitWidth = sizeof(BitsType) << 3;
static constexpr uint32_t mantissaWidth = 23;
static constexpr BitsType mantissaMask = 0x007fffffU;
static constexpr BitsType signMask = 0x80000000U;
static constexpr BitsType exponentMask = ~(signMask | mantissaMask);
static constexpr uint32_t exponentOffset = 127;
// If a number x is a NAN, then it is a quiet NAN if:
// QuietNaNMask & bits(x) != 0
// Else, it is a signalling NAN.
static constexpr BitsType quietNaNMask = 0x00400000U;
};
template <> struct FloatProperties<double> {
typedef uint64_t BitsType;
static_assert(sizeof(BitsType) == sizeof(double),
"Unexpected size of 'double' type.");
static constexpr uint32_t bitWidth = sizeof(BitsType) << 3;
static constexpr uint32_t mantissaWidth = 52;
static constexpr BitsType mantissaMask = 0x000fffffffffffffU;
static constexpr BitsType signMask = 0x8000000000000000ULL;
static constexpr BitsType exponentMask = ~(signMask | mantissaMask);
static constexpr uint32_t exponentOffset = 1023;
// If a number x is a NAN, then it is a quiet NAN if:
// QuietNaNMask & bits(x) != 0
// Else, it is a signalling NAN.
static constexpr BitsType quietNaNMask = 0x0008000000000000ULL;
};
// Define the float type corresponding to the BitsType.
template <typename BitsType> struct FloatType;
template <> struct FloatType<uint32_t> {
static_assert(sizeof(uint32_t) == sizeof(float),
"Unexpected size of 'float' type.");
typedef float Type;
};
template <> struct FloatType<uint64_t> {
static_assert(sizeof(uint64_t) == sizeof(double),
"Unexpected size of 'double' type.");
typedef double Type;
};
template <typename BitsType>
using FloatTypeT = typename FloatType<BitsType>::Type;
} // namespace fputil
} // namespace __llvm_libc
#endif // LLVM_LIBC_UTILS_FPUTIL_FLOAT_PROPERTIES_H
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