forked from OSchip/llvm-project
64 lines
2.1 KiB
C++
64 lines
2.1 KiB
C++
//===-- Common operations on 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_OPERATIONS_H
|
|
#define LLVM_LIBC_UTILS_FPUTIL_FLOAT_OPERATIONS_H
|
|
|
|
#include "BitPatterns.h"
|
|
#include "FloatProperties.h"
|
|
|
|
#include "utils/CPP/TypeTraits.h"
|
|
|
|
namespace __llvm_libc {
|
|
namespace fputil {
|
|
|
|
// Return the bits of a float value.
|
|
template <typename T,
|
|
cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
|
|
static inline typename FloatProperties<T>::BitsType valueAsBits(T x) {
|
|
using BitsType = typename FloatProperties<T>::BitsType;
|
|
return *reinterpret_cast<BitsType *>(&x);
|
|
}
|
|
|
|
// Return the float value from bits.
|
|
template <typename BitsType,
|
|
cpp::EnableIfType<
|
|
cpp::IsFloatingPointType<FloatTypeT<BitsType>>::Value, int> = 0>
|
|
static inline FloatTypeT<BitsType> valueFromBits(BitsType bits) {
|
|
return *reinterpret_cast<FloatTypeT<BitsType> *>(&bits);
|
|
}
|
|
|
|
// Return the bits of abs(x).
|
|
template <typename T,
|
|
cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
|
|
static inline typename FloatProperties<T>::BitsType absBits(T x) {
|
|
return valueAsBits(x) & (~FloatProperties<T>::signMask);
|
|
}
|
|
|
|
template <typename BitsType>
|
|
static inline int getExponentFromBits(BitsType bits) {
|
|
using FPType = typename FloatType<BitsType>::Type;
|
|
using Properties = FloatProperties<FPType>;
|
|
bits &= Properties::exponentMask;
|
|
int e = (bits >> Properties::mantissaWidth); // Shift out the mantissa.
|
|
e -= Properties::exponentOffset; // Zero adjust.
|
|
return e;
|
|
}
|
|
|
|
// Return the zero adjusted exponent value of x.
|
|
template <typename T,
|
|
cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
|
|
static inline int getExponent(T x) {
|
|
return getExponentFromBits(valueAsBits(x));
|
|
}
|
|
|
|
} // namespace fputil
|
|
} // namespace __llvm_libc
|
|
|
|
#endif // LLVM_LIBC_UTILS_FPUTIL_FLOAT_OPERATIONS_H
|