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/__support/macros/config.h" 14 #include "src/stdio/printf_core/core_structs.h" 15 16 #include <inttypes.h> 17 #include <stddef.h> 18 19 namespace LIBC_NAMESPACE_DECL { 20 namespace printf_core { 21 apply_length_modifier(uintmax_t num,LengthSpec length_spec)22LIBC_INLINE uintmax_t apply_length_modifier(uintmax_t num, 23 LengthSpec length_spec) { 24 auto [lm, bw] = length_spec; 25 switch (lm) { 26 case LengthModifier::none: 27 return num & cpp::numeric_limits<unsigned int>::max(); 28 case LengthModifier::l: 29 return num & cpp::numeric_limits<unsigned long>::max(); 30 case LengthModifier::ll: 31 case LengthModifier::L: 32 return num & cpp::numeric_limits<unsigned long long>::max(); 33 case LengthModifier::h: 34 return num & cpp::numeric_limits<unsigned short>::max(); 35 case LengthModifier::hh: 36 return num & cpp::numeric_limits<unsigned char>::max(); 37 case LengthModifier::z: 38 return num & cpp::numeric_limits<size_t>::max(); 39 case LengthModifier::t: 40 // We don't have unsigned ptrdiff so uintptr_t is used, since we need an 41 // unsigned type and ptrdiff is usually the same size as a pointer. 42 static_assert(sizeof(ptrdiff_t) == sizeof(uintptr_t)); 43 return num & cpp::numeric_limits<uintptr_t>::max(); 44 case LengthModifier::j: 45 return num; // j is intmax, so no mask is necessary. 46 case LengthModifier::w: 47 case LengthModifier::wf: { 48 uintmax_t mask; 49 if (bw == 0) { 50 mask = 0; 51 } else if (bw < sizeof(uintmax_t) * CHAR_BIT) { 52 mask = (static_cast<uintmax_t>(1) << bw) - 1; 53 } else { 54 mask = UINTMAX_MAX; 55 } 56 return num & mask; 57 } 58 } 59 __builtin_unreachable(); 60 } 61 62 #define RET_IF_RESULT_NEGATIVE(func) \ 63 { \ 64 int result = (func); \ 65 if (result < 0) \ 66 return result; \ 67 } 68 69 // This is used to represent which direction the number should be rounded. 70 enum class RoundDirection { Up, Down, Even }; 71 72 } // namespace printf_core 73 } // namespace LIBC_NAMESPACE_DECL 74 75 #endif // LLVM_LIBC_SRC_STDIO_PRINTF_CORE_CONVERTER_UTILS_H 76