| /* Copyright (C) 1997, 1998, 1999, 2008 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #ifndef _FENV_H |
| # error "Never use <bits/fenv.h> directly; include <fenv.h> instead." |
| #endif |
| |
| |
| /* Define bits representing the exception. We use the bit positions of |
| the appropriate bits in the FPSCR... */ |
| enum |
| { |
| FE_INEXACT = 1 << (31 - 6), |
| #define FE_INEXACT FE_INEXACT |
| FE_DIVBYZERO = 1 << (31 - 5), |
| #define FE_DIVBYZERO FE_DIVBYZERO |
| FE_UNDERFLOW = 1 << (31 - 4), |
| #define FE_UNDERFLOW FE_UNDERFLOW |
| FE_OVERFLOW = 1 << (31 - 3), |
| #define FE_OVERFLOW FE_OVERFLOW |
| |
| /* ... except for FE_INVALID, for which we use bit 31. FE_INVALID |
| actually corresponds to bits 7 through 12 and 21 through 23 |
| in the FPSCR, but we can't use that because the current draft |
| says that it must be a power of 2. Instead we use bit 2 which |
| is the summary bit for all the FE_INVALID exceptions, which |
| kind of makes sense. */ |
| FE_INVALID = 1 << (31 - 2), |
| #define FE_INVALID FE_INVALID |
| |
| #ifdef __USE_GNU |
| /* Breakdown of the FE_INVALID bits. Setting FE_INVALID on an |
| input to a routine is equivalent to setting all of these bits; |
| FE_INVALID will be set on output from a routine iff one of |
| these bits is set. Note, though, that you can't disable or |
| enable these exceptions individually. */ |
| |
| /* Operation with SNaN. */ |
| FE_INVALID_SNAN = 1 << (31 - 7), |
| # define FE_INVALID_SNAN FE_INVALID_SNAN |
| |
| /* Inf - Inf */ |
| FE_INVALID_ISI = 1 << (31 - 8), |
| # define FE_INVALID_ISI FE_INVALID_ISI |
| |
| /* Inf / Inf */ |
| FE_INVALID_IDI = 1 << (31 - 9), |
| # define FE_INVALID_IDI FE_INVALID_IDI |
| |
| /* 0 / 0 */ |
| FE_INVALID_ZDZ = 1 << (31 - 10), |
| # define FE_INVALID_ZDZ FE_INVALID_ZDZ |
| |
| /* Inf * 0 */ |
| FE_INVALID_IMZ = 1 << (31 - 11), |
| # define FE_INVALID_IMZ FE_INVALID_IMZ |
| |
| /* Comparison with NaN or SNaN. */ |
| FE_INVALID_COMPARE = 1 << (31 - 12), |
| # define FE_INVALID_COMPARE FE_INVALID_COMPARE |
| |
| /* Invalid operation flag for software (not set by hardware). */ |
| /* Note that some chips don't have this implemented, presumably |
| because no-one expected anyone to write software for them %-). */ |
| FE_INVALID_SOFTWARE = 1 << (31 - 21), |
| # define FE_INVALID_SOFTWARE FE_INVALID_SOFTWARE |
| |
| /* Square root of negative number (including -Inf). */ |
| /* Note that some chips don't have this implemented. */ |
| FE_INVALID_SQRT = 1 << (31 - 22), |
| # define FE_INVALID_SQRT FE_INVALID_SQRT |
| |
| /* Conversion-to-integer of a NaN or a number too large or too small. */ |
| FE_INVALID_INTEGER_CONVERSION = 1 << (31 - 23) |
| # define FE_INVALID_INTEGER_CONVERSION FE_INVALID_INTEGER_CONVERSION |
| |
| # define FE_ALL_INVALID \ |
| (FE_INVALID_SNAN | FE_INVALID_ISI | FE_INVALID_IDI | FE_INVALID_ZDZ \ |
| | FE_INVALID_IMZ | FE_INVALID_COMPARE | FE_INVALID_SOFTWARE \ |
| | FE_INVALID_SQRT | FE_INVALID_INTEGER_CONVERSION) |
| #endif |
| }; |
| |
| #define FE_ALL_EXCEPT \ |
| (FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID) |
| |
| /* PowerPC chips support all of the four defined rounding modes. We |
| use the bit pattern in the FPSCR as the values for the |
| appropriate macros. */ |
| enum |
| { |
| FE_TONEAREST = 0, |
| #define FE_TONEAREST FE_TONEAREST |
| FE_TOWARDZERO = 1, |
| #define FE_TOWARDZERO FE_TOWARDZERO |
| FE_UPWARD = 2, |
| #define FE_UPWARD FE_UPWARD |
| FE_DOWNWARD = 3 |
| #define FE_DOWNWARD FE_DOWNWARD |
| }; |
| |
| /* Type representing exception flags. */ |
| typedef unsigned int fexcept_t; |
| |
| /* Type representing floating-point environment. We leave it as 'double' |
| for efficiency reasons (rather than writing it to a 32-bit integer). */ |
| typedef double fenv_t; |
| |
| /* If the default argument is used we use this value. */ |
| extern const fenv_t __fe_dfl_env; |
| #define FE_DFL_ENV (&__fe_dfl_env) |
| |
| #ifdef __USE_GNU |
| /* Floating-point environment where all exceptions are enabled. Note that |
| this is not sufficient to give you SIGFPE. */ |
| extern const fenv_t __fe_enabled_env; |
| # define FE_ENABLED_ENV (&__fe_enabled_env) |
| |
| /* Floating-point environment with (processor-dependent) non-IEEE floating |
| point. */ |
| extern const fenv_t __fe_nonieee_env; |
| # define FE_NONIEEE_ENV (&__fe_nonieee_env) |
| |
| __BEGIN_DECLS |
| |
| /* Floating-point environment with all exceptions enabled. Note that |
| just evaluating this value does not change the processor exception mode. |
| Passing this mask to fesetenv will result in a prctl syscall to change |
| the MSR FE0/FE1 bits to "Precise Mode". On some processors this will |
| result in slower floating point execution. This will last until an |
| fenv or exception mask is installed that disables all FP exceptions. */ |
| extern const fenv_t *__fe_nomask_env (void); |
| # define FE_NOMASK_ENV FE_ENABLED_ENV |
| |
| /* Floating-point environment with all exceptions disabled. Note that |
| just evaluating this value does not change the processor exception mode. |
| Passing this mask to fesetenv will result in a prctl syscall to change |
| the MSR FE0/FE1 bits to "Ignore Exceptions Mode". On most processors |
| this allows the fastest possible floating point execution.*/ |
| extern const fenv_t *__fe_mask_env (void); |
| # define FE_MASK_ENV FE_DFL_ENV |
| |
| __END_DECLS |
| |
| #endif |