1 //===-- Shared Converter Utilities for printf -------------------*- 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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_LIBC_SRC_STDIO_PRINTF_CORE_CONVERTER_UTILS_H 10 #define LLVM_LIBC_SRC_STDIO_PRINTF_CORE_CONVERTER_UTILS_H 11 12 #include "src/__support/CPP/limits.h" 13 #include "src/stdio/printf_core/core_structs.h" 14 15 #include <inttypes.h> 16 #include <stddef.h> 17 18 namespace LIBC_NAMESPACE { 19 namespace printf_core { 20 apply_length_modifier(uintmax_t num,LengthSpec length_spec)21LIBC_INLINE uintmax_t apply_length_modifier(uintmax_t num, 22 LengthSpec length_spec) { 23 auto [lm, bw] = length_spec; 24 switch (lm) { 25 case LengthModifier::none: 26 return num & cpp::numeric_limits<unsigned int>::max(); 27 case LengthModifier::l: 28 return num & cpp::numeric_limits<unsigned long>::max(); 29 case LengthModifier::ll: 30 case LengthModifier::L: 31 return num & cpp::numeric_limits<unsigned long long>::max(); 32 case LengthModifier::h: 33 return num & cpp::numeric_limits<unsigned short>::max(); 34 case LengthModifier::hh: 35 return num & cpp::numeric_limits<unsigned char>::max(); 36 case LengthModifier::z: 37 return num & cpp::numeric_limits<size_t>::max(); 38 case LengthModifier::t: 39 // We don't have unsigned ptrdiff so uintptr_t is used, since we need an 40 // unsigned type and ptrdiff is usually the same size as a pointer. 41 static_assert(sizeof(ptrdiff_t) == sizeof(uintptr_t)); 42 return num & cpp::numeric_limits<uintptr_t>::max(); 43 case LengthModifier::j: 44 return num; // j is intmax, so no mask is necessary. 45 case LengthModifier::w: 46 case LengthModifier::wf: { 47 uintmax_t mask; 48 if (bw == 0) { 49 mask = 0; 50 } else if (bw < sizeof(uintmax_t) * CHAR_BIT) { 51 mask = (static_cast<uintmax_t>(1) << bw) - 1; 52 } else { 53 mask = UINTMAX_MAX; 54 } 55 return num & mask; 56 } 57 } 58 __builtin_unreachable(); 59 } 60 61 #define RET_IF_RESULT_NEGATIVE(func) \ 62 { \ 63 int result = (func); \ 64 if (result < 0) \ 65 return result; \ 66 } 67 68 // This is used to represent which direction the number should be rounded. 69 enum class RoundDirection { Up, Down, Even }; 70 71 } // namespace printf_core 72 } // namespace LIBC_NAMESPACE 73 74 #endif // LLVM_LIBC_SRC_STDIO_PRINTF_CORE_CONVERTER_UTILS_H 75