Files
clang-p2996/libc/utils/FPUtil/BasicOperations.h
Siva Chandra Reddy 139018265b [libc] Add implementations long double fabsl and truncl functions.
Current implementations of single precision and double precision
floating point operations operate on bits of the integer type of
same size. The code made use of magic masks which were listed as
literal integer values. This is not possible in the case of long
double type as the mantissa of quad-precision long double type used
on non-x86 architectures is wider that the widest integer type for
which we can list literal values. So, in this patch, to avoid
using magic masks specified with literal values, we use packed
bit-field struct types and let the compiler generate the masks.
This new scheme allows us to implement long double flavors of the
various floating point operations. To keep the size of the patch
small, only the implementations of fabs and trunc have been
switched to the new scheme. In following patches, all exisiting
implementations will be switched to the new scheme.

Reviewers: asteinhauser

Differential Revision: https://reviews.llvm.org/D82036
2020-06-18 11:08:26 -07:00

31 lines
855 B
C++

//===-- Basic 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_BASIC_OPERATIONS_H
#define LLVM_LIBC_UTILS_FPUTIL_BASIC_OPERATIONS_H
#include "FPBits.h"
#include "utils/CPP/TypeTraits.h"
namespace __llvm_libc {
namespace fputil {
template <typename T,
cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
static inline T abs(T x) {
FPBits<T> bits(x);
bits.sign = 0;
return T(bits);
}
} // namespace fputil
} // namespace __llvm_libc
#endif // LLVM_LIBC_UTILS_FPUTIL_BASIC_OPERATIONS_H