1 /* Copyright (C) 2000-2022 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 values of the 23 appropriate enable bits in the FPU status word (which, 24 coincidentally, are the same as the flag bits, but shifted right by 25 27 bits). */ 26 enum 27 { 28 FE_INVALID = 29 #define FE_INVALID (1<<4) /* V */ 30 FE_INVALID, 31 FE_DIVBYZERO = 32 #define FE_DIVBYZERO (1<<3) /* Z */ 33 FE_DIVBYZERO, 34 FE_OVERFLOW = 35 #define FE_OVERFLOW (1<<2) /* O */ 36 FE_OVERFLOW, 37 FE_UNDERFLOW = 38 #define FE_UNDERFLOW (1<<1) /* U */ 39 FE_UNDERFLOW, 40 FE_INEXACT = 41 #define FE_INEXACT (1<<0) /* I */ 42 FE_INEXACT, 43 }; 44 45 #define FE_ALL_EXCEPT \ 46 (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID) 47 48 /* The PA-RISC FPU supports all of the four defined rounding modes. 49 We use the values of the RM field in the floating point status 50 register for the appropriate macros. */ 51 enum 52 { 53 FE_TONEAREST = 54 #define FE_TONEAREST (0 << 9) 55 FE_TONEAREST, 56 FE_TOWARDZERO = 57 #define FE_TOWARDZERO (1 << 9) 58 FE_TOWARDZERO, 59 FE_UPWARD = 60 #define FE_UPWARD (2 << 9) 61 FE_UPWARD, 62 FE_DOWNWARD = 63 #define FE_DOWNWARD (3 << 9) 64 FE_DOWNWARD, 65 }; 66 67 /* Type representing exception flags. */ 68 typedef unsigned int fexcept_t; 69 70 /* Type representing floating-point environment. This structure 71 corresponds to the layout of the status and exception words in the 72 register file. The exception registers are never saved/stored by 73 userspace. This structure is also not correctly aligned ever, in 74 an ABI error we left out __aligned(8) and subsequently all of our 75 fenv functions must accept unaligned input, align the input, and 76 then use assembly to store fr0. This is a performance hit, but 77 means the ABI is stable. */ 78 typedef struct 79 { 80 unsigned int __status_word; 81 unsigned int __exception[7]; 82 } fenv_t; 83 84 /* If the default argument is used we use this value. */ 85 #define FE_DFL_ENV ((const fenv_t *) -1) 86 87 #ifdef __USE_GNU 88 /* Floating-point environment where none of the exceptions are masked. */ 89 # define FE_NOMASK_ENV ((const fenv_t *) -2) 90 #endif 91 92 #if __GLIBC_USE (IEC_60559_BFP_EXT_C2X) 93 /* Type representing floating-point control modes. */ 94 typedef unsigned int femode_t; 95 96 /* Default floating-point control modes. */ 97 # define FE_DFL_MODE ((const femode_t *) -1L) 98 #endif 99