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1//===------ Pretty print function for FPBits --------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLVM_LIBC_SRC___SUPPORT_FPUTIL_FPBITS_STR_H10#define LLVM_LIBC_SRC___SUPPORT_FPUTIL_FPBITS_STR_H11 12#include "src/__support/CPP/string.h"13#include "src/__support/CPP/type_traits.h"14#include "src/__support/FPUtil/FPBits.h"15#include "src/__support/integer_to_string.h"16#include "src/__support/macros/attributes.h"17#include "src/__support/macros/config.h"18 19namespace LIBC_NAMESPACE_DECL {20 21namespace details {22 23// Format T as uppercase hexadecimal number with leading zeros.24template <typename T>25using ZeroPaddedHexFmt = IntegerToString<26 T, typename radix::Hex::WithWidth<(sizeof(T) * 2)>::WithPrefix::Uppercase>;27 28} // namespace details29 30// Converts the bits to a string in the following format:31// "0x<NNN...N> = S: N, E: 0xNNNN, M:0xNNN...N"32// 1. N is a hexadecimal digit.33// 2. The hexadecimal number on the LHS is the raw numerical representation34// of the bits.35// 3. The exponent is always 16 bits wide irrespective of the type of the36// floating encoding.37template <typename T> LIBC_INLINE cpp::string str(fputil::FPBits<T> x) {38 using StorageType = typename fputil::FPBits<T>::StorageType;39 40 if (x.is_nan())41 return "(NaN)";42 if (x.is_inf())43 return x.is_neg() ? "(-Infinity)" : "(+Infinity)";44 45 const auto sign_char = [](Sign sign) -> char {46 return sign.is_neg() ? '1' : '0';47 };48 49 cpp::string s;50 51 const details::ZeroPaddedHexFmt<StorageType> bits(x.uintval());52 s += bits.view();53 54 s += " = (S: ";55 s += sign_char(x.sign());56 57 s += ", E: ";58 const details::ZeroPaddedHexFmt<uint16_t> exponent(x.get_biased_exponent());59 s += exponent.view();60 61 if constexpr (fputil::get_fp_type<T>() == fputil::FPType::X86_Binary80) {62 s += ", I: ";63 s += sign_char(x.get_implicit_bit() ? Sign::NEG : Sign::POS);64 }65 66 s += ", M: ";67 const details::ZeroPaddedHexFmt<StorageType> mantissa(x.get_mantissa());68 s += mantissa.view();69 70 s += ')';71 return s;72}73 74} // namespace LIBC_NAMESPACE_DECL75 76#endif // LLVM_LIBC_SRC___SUPPORT_FPUTIL_FPBITS_STR_H77