lib/msvcrt/float/fpclass.c

   1 #include <msvcrt/float.h>
   2 #include <msvcrt/math.h>
   3 #include <msvcrt/internal/ieee.h>
   4
   5 #define _FPCLASS_SNAN   0x0001  /* signaling NaN */
   6 #define _FPCLASS_QNAN   0x0002  /* quiet NaN */
   7 #define _FPCLASS_NINF   0x0004  /* negative infinity */
   8 #define _FPCLASS_NN     0x0008  /* negative normal */
   9 #define _FPCLASS_ND     0x0010  /* negative denormal */
  10 #define _FPCLASS_NZ     0x0020  /* -0 */
  11 #define _FPCLASS_PZ     0x0040  /* +0 */
  12 #define _FPCLASS_PD     0x0080  /* positive denormal */
  13 #define _FPCLASS_PN     0x0100  /* positive normal */
  14 #define _FPCLASS_PINF   0x0200  /* positive infinity */
  15
  16 #define FP_SNAN       0x0001  //    signaling NaN
  17 #define FP_QNAN       0x0002  //    quiet NaN
  18 #define FP_NINF       0x0004  //    negative infinity
  19 #define FP_PINF       0x0200  //    positive infinity
  20 #define FP_NDENORM    0x0008  //    negative denormalized non-zero
  21 #define FP_PDENORM    0x0010  //    positive denormalized non-zero
  22 #define FP_NZERO      0x0020  //    negative zero
  23 #define FP_PZERO      0x0040  //    positive zero
  24 #define FP_NNORM      0x0080  //    negative normalized non-zero
  25 #define FP_PNORM      0x0100  //    positive normalized non-zero
  26
  27 typedef int fpclass_t;
  28
  29 fpclass_t _fpclass(double __d)
  30 {
  31         double_t *d = (double_t *)&__d;
  32
  33         if ( d->exponent == 0 ) {
  34                 if ( d->mantissah == 0 &&  d->mantissal == 0 ) {
  35                         if ( d->sign ==0 )
  36                                 return FP_NZERO;
  37                         else
  38                                 return FP_PZERO;
  39                 } else {
  40                         if ( d->sign ==0 )
  41                                 return FP_NDENORM;
  42                         else
  43                                 return FP_PDENORM;
  44                 }
  45         }
  46         if (d->exponent == 0x7ff ) {
  47                 if ( d->mantissah == 0 &&  d->mantissal == 0 ) {
  48                         if ( d->sign ==0 )
  49                                 return FP_NINF;
  50                         else
  51                                 return FP_PINF;
  52                 }
  53                 else if ( d->mantissah == 0 &&  d->mantissal != 0 ) {
  54                         return FP_QNAN;
  55                 }
  56                 else if ( d->mantissah == 0 &&  d->mantissal != 0 ) {
  57                         return FP_SNAN;
  58                 }
  59
  60         }
  61
  62         return 0;
  63 }
  64
  65