sysdeps/ieee754/flt-32/math_config.h

   1 /* Configuration for math routines.
   2    Copyright (C) 2017 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _MATH_CONFIG_H
  20 #define _MATH_CONFIG_H
  21
  22 #include <math.h>
  23 #include <math_private.h>
  24 #include <stdint.h>
  25
  26 #ifndef WANT_ROUNDING
  27 /* Correct special case results in non-nearest rounding modes.  */
  28 # define WANT_ROUNDING 1
  29 #endif
  30 #ifndef WANT_ERRNO
  31 /* Set errno according to ISO C with (math_errhandling & MATH_ERRNO) != 0.  */
  32 # define WANT_ERRNO 1
  33 #endif
  34 #ifndef WANT_ERRNO_UFLOW
  35 /* Set errno to ERANGE if result underflows to 0 (in all rounding modes).  */
  36 # define WANT_ERRNO_UFLOW (WANT_ROUNDING && WANT_ERRNO)
  37 #endif
  38
  39 #ifndef TOINT_INTRINSICS
  40 # define TOINT_INTRINSICS 0
  41 #endif
  42 #ifndef TOINT_RINT
  43 # define TOINT_RINT 0
  44 #endif
  45 #ifndef TOINT_SHIFT
  46 # define TOINT_SHIFT 1
  47 #endif
  48
  49 static inline uint32_t
  50 asuint (float f)
  51 {
  52   union
  53   {
  54     float f;
  55     uint32_t i;
  56   } u = {f};
  57   return u.i;
  58 }
  59
  60 static inline float
  61 asfloat (uint32_t i)
  62 {
  63   union
  64   {
  65     uint32_t i;
  66     float f;
  67   } u = {i};
  68   return u.f;
  69 }
  70
  71 static inline uint64_t
  72 asuint64 (double f)
  73 {
  74   union
  75   {
  76     double f;
  77     uint64_t i;
  78   } u = {f};
  79   return u.i;
  80 }
  81
  82 static inline double
  83 asdouble (uint64_t i)
  84 {
  85   union
  86   {
  87     uint64_t i;
  88     double f;
  89   } u = {i};
  90   return u.f;
  91 }
  92
  93 #define NOINLINE __attribute__ ((noinline))
  94
  95 attribute_hidden float __math_oflowf (unsigned long);
  96 attribute_hidden float __math_uflowf (unsigned long);
  97 attribute_hidden float __math_may_uflowf (unsigned long);
  98 attribute_hidden float __math_divzerof (unsigned long);
  99 attribute_hidden float __math_invalidf (float);
 100
 101 /* Shared between expf, exp2f and powf.  */
 102 #define EXP2F_TABLE_BITS 5
 103 #define EXP2F_POLY_ORDER 3
 104 extern const struct exp2f_data
 105 {
 106   uint64_t tab[1 << EXP2F_TABLE_BITS];
 107   double shift_scaled;
 108   double poly[EXP2F_POLY_ORDER];
 109   double shift;
 110   double invln2_scaled;
 111   double poly_scaled[EXP2F_POLY_ORDER];
 112 } __exp2f_data attribute_hidden;
 113
 114 #endif