win32/include/tcc/tcc_libm.h

   1 #ifndef _TCC_LIBM_H_
   2 #define _TCC_LIBM_H_
   3
   4 #include "../math.h"
   5
   6 /* TCC uses 8 bytes for double and long double, so effectively the l variants
   7  * are never used. For now, they just run the normal (double) variant.
   8  */
   9
  10 /*
  11  * most of the code in this file is taken from MUSL rs-1.0 (MIT license)
  12  * - musl-libc: http://git.musl-libc.org/cgit/musl/tree/src/math?h=rs-1.0
  13  * - License:   http://git.musl-libc.org/cgit/musl/tree/COPYRIGHT?h=rs-1.0
  14  */
  15
  16 /*******************************************************************************
  17   Start of code based on MUSL
  18 *******************************************************************************/
  19 /*
  20 musl as a whole is licensed under the following standard MIT license:
  21
  22 ----------------------------------------------------------------------
  23 Copyright © 2005-2014 Rich Felker, et al.
  24
  25 Permission is hereby granted, free of charge, to any person obtaining
  26 a copy of this software and associated documentation files (the
  27 "Software"), to deal in the Software without restriction, including
  28 without limitation the rights to use, copy, modify, merge, publish,
  29 distribute, sublicense, and/or sell copies of the Software, and to
  30 permit persons to whom the Software is furnished to do so, subject to
  31 the following conditions:
  32
  33 The above copyright notice and this permission notice shall be
  34 included in all copies or substantial portions of the Software.
  35
  36 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  37 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  38 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  39 IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  40 CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  41 TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  42 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  43 ----------------------------------------------------------------------
  44 */
  45
  46 /* fpclassify */
  47
  48 __CRT_INLINE int __cdecl __fpclassify (double x) {
  49   union {double f; uint64_t i;} u = {x};
  50   int e = u.i>>52 & 0x7ff;
  51   if (!e) return u.i<<1 ? FP_SUBNORMAL : FP_ZERO;
  52   if (e==0x7ff) return u.i<<12 ? FP_NAN : FP_INFINITE;
  53   return FP_NORMAL;
  54 }
  55
  56 __CRT_INLINE int __cdecl __fpclassifyf (float x) {
  57   union {float f; uint32_t i;} u = {x};
  58   int e = u.i>>23 & 0xff;
  59   if (!e) return u.i<<1 ? FP_SUBNORMAL : FP_ZERO;
  60   if (e==0xff) return u.i<<9 ? FP_NAN : FP_INFINITE;
  61   return FP_NORMAL;
  62 }
  63
  64 __CRT_INLINE int __cdecl __fpclassifyl (long double x) {
  65   return __fpclassify(x);
  66 }
  67
  68
  69 /* signbit */
  70
  71 __CRT_INLINE int __cdecl __signbit (double x) {
  72   union {double d; uint64_t i;} y = { x };
  73   return y.i>>63;
  74 }
  75
  76 __CRT_INLINE int __cdecl __signbitf (float x) {
  77   union {float f; uint32_t i; } y = { x };
  78   return y.i>>31;
  79 }
  80
  81 __CRT_INLINE int __cdecl __signbitl (long double x) {
  82   return __signbit(x);
  83 }
  84
  85
  86 /* fmin*, fmax* */
  87
  88 #define TCCFP_FMIN_EVAL (isnan(x) ? y :                                      \
  89                          isnan(y) ? x :                                      \
  90                          (signbit(x) != signbit(y)) ? (signbit(x) ? x : y) : \
  91                          x < y ? x : y)
  92
  93 __CRT_INLINE double __cdecl fmin (double x, double y) {
  94   return TCCFP_FMIN_EVAL;
  95 }
  96
  97 __CRT_INLINE float __cdecl fminf (float x, float y) {
  98   return TCCFP_FMIN_EVAL;
  99 }
 100
 101 __CRT_INLINE long double __cdecl fminl (long double x, long double y) {
 102   return TCCFP_FMIN_EVAL;
 103 }
 104
 105 #define TCCFP_FMAX_EVAL (isnan(x) ? y :                                      \
 106                          isnan(y) ? x :                                      \
 107                          (signbit(x) != signbit(y)) ? (signbit(x) ? y : x) : \
 108                          x < y ? y : x)
 109
 110 __CRT_INLINE double __cdecl fmax (double x, double y) {
 111   return TCCFP_FMAX_EVAL;
 112 }
 113
 114 __CRT_INLINE float __cdecl fmaxf (float x, float y) {
 115   return TCCFP_FMAX_EVAL;
 116 }
 117
 118 __CRT_INLINE long double __cdecl fmaxl (long double x, long double y) {
 119   return TCCFP_FMAX_EVAL;
 120 }
 121
 122
 123 /* *round* */
 124
 125 #define TCCFP_FORCE_EVAL(x) do {            \
 126 if (sizeof(x) == sizeof(float)) {           \
 127   volatile float __x;                       \
 128   __x = (x);                                \
 129 } else if (sizeof(x) == sizeof(double)) {   \
 130   volatile double __x;                      \
 131   __x = (x);                                \
 132 } else {                                    \
 133   volatile long double __x;                 \
 134   __x = (x);                                \
 135 }                                           \
 136 } while(0)
 137
 138 __CRT_INLINE double __cdecl round (double x) {
 139   union {double f; uint64_t i;} u = {x};
 140   int e = u.i >> 52 & 0x7ff;
 141   double y;
 142
 143   if (e >= 0x3ff+52)
 144     return x;
 145   if (u.i >> 63)
 146     x = -x;
 147   if (e < 0x3ff-1) {
 148     /* raise inexact if x!=0 */
 149     TCCFP_FORCE_EVAL(x + 0x1p52);
 150     return 0*u.f;
 151   }
 152   y = (double)(x + 0x1p52) - 0x1p52 - x;
 153   if (y > 0.5)
 154     y = y + x - 1;
 155   else if (y <= -0.5)
 156     y = y + x + 1;
 157   else
 158     y = y + x;
 159   if (u.i >> 63)
 160     y = -y;
 161   return y;
 162 }
 163
 164 __CRT_INLINE long __cdecl lround (double x) {
 165   return round(x);
 166 }
 167
 168 __CRT_INLINE long long __cdecl llround (double x) {
 169   return round(x);
 170 }
 171
 172 __CRT_INLINE float __cdecl roundf (float x) {
 173   return round(x);
 174 }
 175
 176 __CRT_INLINE long __cdecl lroundf (float x) {
 177   return round(x);
 178 }
 179
 180 __CRT_INLINE long long __cdecl llroundf (float x) {
 181   return round(x);
 182 }
 183
 184 __CRT_INLINE long double __cdecl roundl (long double x) {
 185   return round(x);
 186 }
 187
 188 __CRT_INLINE long __cdecl lroundl (long double x) {
 189   return round(x);
 190 }
 191
 192 __CRT_INLINE long long __cdecl llroundl (long double x) {
 193   return round(x);
 194 }
 195
 196
 197 /*******************************************************************************
 198   End of code based on MUSL
 199 *******************************************************************************/
 200
 201 #endif /* _TCC_LIBM_H_ */