1 /* Copyright (C) 1997-2022 Free Software Foundation, Inc. 2 This file is part of the GNU C Library. 3 4 The GNU C Library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU Lesser General Public 6 License as published by the Free Software Foundation; either 7 version 2.1 of the License, or (at your option) any later version. 8 9 The GNU C Library is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public 15 License along with the GNU C Library; if not, see 16 <https://www.gnu.org/licenses/>. */ 17 18 #ifndef _FENV_H 19 # error "Never use <bits/fenv.h> directly; include <fenv.h> instead." 20 #endif 21 22 /* Define bits representing the exception. We use the bit positions 23 of the appropriate bits in the FPU control word. */ 24 enum 25 { 26 FE_INVALID = 27 #define FE_INVALID 0x01 28 FE_INVALID, 29 __FE_DENORM = 0x02, 30 FE_DIVBYZERO = 31 #define FE_DIVBYZERO 0x04 32 FE_DIVBYZERO, 33 FE_OVERFLOW = 34 #define FE_OVERFLOW 0x08 35 FE_OVERFLOW, 36 FE_UNDERFLOW = 37 #define FE_UNDERFLOW 0x10 38 FE_UNDERFLOW, 39 FE_INEXACT = 40 #define FE_INEXACT 0x20 41 FE_INEXACT 42 }; 43 44 #define FE_ALL_EXCEPT \ 45 (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID) 46 47 /* The ix87 FPU supports all of the four defined rounding modes. We 48 use again the bit positions in the FPU control word as the values 49 for the appropriate macros. */ 50 enum 51 { 52 FE_TONEAREST = 53 #define FE_TONEAREST 0 54 FE_TONEAREST, 55 FE_DOWNWARD = 56 #define FE_DOWNWARD 0x400 57 FE_DOWNWARD, 58 FE_UPWARD = 59 #define FE_UPWARD 0x800 60 FE_UPWARD, 61 FE_TOWARDZERO = 62 #define FE_TOWARDZERO 0xc00 63 FE_TOWARDZERO 64 }; 65 66 67 /* Type representing exception flags. */ 68 typedef unsigned short int fexcept_t; 69 70 71 /* Type representing floating-point environment. This structure 72 corresponds to the layout of the block written by the `fstenv' 73 instruction and has additional fields for the contents of the MXCSR 74 register as written by the `stmxcsr' instruction. */ 75 typedef struct 76 { 77 unsigned short int __control_word; 78 unsigned short int __glibc_reserved1; 79 unsigned short int __status_word; 80 unsigned short int __glibc_reserved2; 81 unsigned short int __tags; 82 unsigned short int __glibc_reserved3; 83 unsigned int __eip; 84 unsigned short int __cs_selector; 85 unsigned int __opcode:11; 86 unsigned int __glibc_reserved4:5; 87 unsigned int __data_offset; 88 unsigned short int __data_selector; 89 unsigned short int __glibc_reserved5; 90 #ifdef __x86_64__ 91 unsigned int __mxcsr; 92 #endif 93 } 94 fenv_t; 95 96 /* If the default argument is used we use this value. */ 97 #define FE_DFL_ENV ((const fenv_t *) -1) 98 99 #ifdef __USE_GNU 100 /* Floating-point environment where none of the exception is masked. */ 101 # define FE_NOMASK_ENV ((const fenv_t *) -2) 102 #endif 103 104 #if __GLIBC_USE (IEC_60559_BFP_EXT_C2X) 105 /* Type representing floating-point control modes. */ 106 typedef struct 107 { 108 unsigned short int __control_word; 109 unsigned short int __glibc_reserved; 110 unsigned int __mxcsr; 111 } 112 femode_t; 113 114 /* Default floating-point control modes. */ 115 # define FE_DFL_MODE ((const femode_t *) -1L) 116 #endif 117