lib/crtdll/float/fpclass.c

   1 #include <msvcrt/float.h>
   2 #include <msvcrt/math.h>
   3 #include <msvcrt/internal/ieee.h>
   4
   5
   6 #define _FPCLASS_SNAN   0x0001  /* signaling NaN */
   7 #define _FPCLASS_QNAN   0x0002  /* quiet NaN */
   8 #define _FPCLASS_NINF   0x0004  /* negative infinity */
   9 #define _FPCLASS_NN     0x0008  /* negative normal */
  10 #define _FPCLASS_ND     0x0010  /* negative denormal */
  11 #define _FPCLASS_NZ     0x0020  /* -0 */
  12 #define _FPCLASS_PZ     0x0040  /* +0 */
  13 #define _FPCLASS_PD     0x0080  /* positive denormal */
  14 #define _FPCLASS_PN     0x0100  /* positive normal */
  15 #define _FPCLASS_PINF   0x0200  /* positive infinity */
  16
  17 #define FP_SNAN       0x0001  //    signaling NaN
  18 #define FP_QNAN       0x0002  //    quiet NaN
  19 #define FP_NINF       0x0004  //    negative infinity
  20 #define FP_PINF       0x0200  //    positive infinity
  21 #define FP_NDENORM    0x0008  //    negative denormalized non-zero
  22 #define FP_PDENORM    0x0010  //    positive denormalized non-zero
  23 #define FP_NZERO      0x0020  //    negative zero
  24 #define FP_PZERO      0x0040  //    positive zero
  25 #define FP_NNORM      0x0080  //    negative normalized non-zero
  26 #define FP_PNORM      0x0100  //    positive normalized non-zero
  27
  28 typedef int fpclass_t;
  29
  30 /*
  31  * @implemented
  32  */
  33 fpclass_t _fpclass(double __d)
  34 {
  35         double_t* d = (double_t*)&__d;
  36
  37         if (d->exponent == 0) {
  38                 if (d->mantissah == 0 &&  d->mantissal == 0) {
  39                         if (d->sign ==0)
  40                                 return FP_NZERO;
  41                         else
  42                                 return FP_PZERO;
  43                 } else {
  44                         if (d->sign ==0)
  45                                 return FP_NDENORM;
  46                         else
  47                                 return FP_PDENORM;
  48                 }
  49         }
  50         if (d->exponent == 0x7ff) {
  51                 if (d->mantissah == 0 &&  d->mantissal == 0) {
  52                         if (d->sign ==0)
  53                                 return FP_NINF;
  54                         else
  55                                 return FP_PINF;
  56                 }
  57                 else if (d->mantissah == 0 &&  d->mantissal != 0) {
  58                         return FP_QNAN;
  59                 }
  60                 else if (d->mantissah == 0 &&  d->mantissal != 0) {
  61                         return FP_SNAN;
  62                 }
  63
  64         }
  65         return 0;
  66 }