compiler/mlib/sincos.c

   1
   2 #include <aros/debug.h>
   3
   4 #include "math.h"
   5 #include "math_private.h"
   6
   7 void sincos(double x, double *sin, double *cos)
   8 {
   9         double y[2],z=0.0;
  10         int32_t n, ix;
  11
  12     /* High word of x. */
  13         GET_HIGH_WORD(ix,x);
  14
  15     /* |x| ~< pi/4 */
  16         ix &= 0x7fffffff;
  17         if(ix <= 0x3fe921fb) {
  18             if(ix<0x3e400000)                   /* |x| < 2**-27 */
  19                {if((int)x==0) { *sin=x; *cos=1.0; return; }}    /* generate inexact */
  20             *sin = __kernel_sin(x,z,0);
  21             *cos = __kernel_cos(x,z);
  22             return;
  23         }
  24
  25         /* cos(Inf or NaN) is NaN */
  26         else if (ix>=0x7ff00000) {*sin = *cos = x-x; return; }
  27
  28         /* argument reduction needed */
  29         else {
  30                 n = __ieee754_rem_pio2(x,y);
  31                 switch(n&3) {
  32                 case 0: *sin =  __kernel_sin(y[0],y[1],1); *cos =  __kernel_cos(y[0],y[1]);   break;
  33                 case 1: *sin =  __kernel_cos(y[0],y[1]);   *cos = -__kernel_sin(y[0],y[1],1); break;
  34                 case 2: *sin = -__kernel_sin(y[0],y[1],1); *cos = -__kernel_cos(y[0],y[1]);   break;
  35                 default:
  36                         *sin = -__kernel_cos(y[0],y[1]); *cos = __kernel_sin(y[0],y[1],1);
  37                 }
  38         }
  39 }