kc3-lang/SDL/src/libm/s_cos.c

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• Hash : 24c86b55
  Author :
  Date : 2014-09-11T19:24:42
  

  [X11] Reconcile logical keyboard state with physical state on FocusIn
  since the window system doesn't do it for us like other platforms.
  
  This prevents sticky keys and missed keys when going in and out
  of focus, for example Alt would appear to stick if switching away
  from an SDL app with Alt-Tab and had to be pressed again.
  
  CR: Sam
  

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• src/libm/s_cos.c

• /* @(#)s_cos.c 5.1 93/09/24 */
  /*
   * ====================================================
   * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   *
   * Developed at SunPro, a Sun Microsystems, Inc. business.
   * Permission to use, copy, modify, and distribute this
   * software is freely granted, provided that this notice
   * is preserved.
   * ====================================================
   */
  
  #if defined(LIBM_SCCS) && !defined(lint)
  static const char rcsid[] =
      "$NetBSD: s_cos.c,v 1.7 1995/05/10 20:47:02 jtc Exp $";
  #endif
  
  /* cos(x)
   * Return cosine function of x.
   *
   * kernel function:
   *	__kernel_sin		... sine function on [-pi/4,pi/4]
   *	__kernel_cos		... cosine function on [-pi/4,pi/4]
   *	__ieee754_rem_pio2	... argument reduction routine
   *
   * Method.
   *      Let S,C and T denote the sin, cos and tan respectively on
   *	[-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
   *	in [-pi/4 , +pi/4], and let n = k mod 4.
   *	We have
   *
   *          n        sin(x)      cos(x)        tan(x)
   *     ----------------------------------------------------------
   *	    0	       S	   C		 T
   *	    1	       C	  -S		-1/T
   *	    2	      -S	  -C		 T
   *	    3	      -C	   S		-1/T
   *     ----------------------------------------------------------
   *
   * Special cases:
   *      Let trig be any of sin, cos, or tan.
   *      trig(+-INF)  is NaN, with signals;
   *      trig(NaN)    is that NaN;
   *
   * Accuracy:
   *	TRIG(x) returns trig(x) nearly rounded
   */
  
  #include "math_libm.h"
  #include "math_private.h"
  
  libm_hidden_proto(cos)
  #ifdef __STDC__
       double cos(double x)
  #else
       double cos(x)
       double x;
  #endif
  {
      double y[2], z = 0.0;
      int32_t n, ix;
  
      /* High word of x. */
      GET_HIGH_WORD(ix, x);
  
      /* |x| ~< pi/4 */
      ix &= 0x7fffffff;
      if (ix <= 0x3fe921fb)
          return __kernel_cos(x, z);
  
      /* cos(Inf or NaN) is NaN */
      else if (ix >= 0x7ff00000)
          return x - x;
  
      /* argument reduction needed */
      else {
          n = __ieee754_rem_pio2(x, y);
          switch (n & 3) {
          case 0:
              return __kernel_cos(y[0], y[1]);
          case 1:
              return -__kernel_sin(y[0], y[1], 1);
          case 2:
              return -__kernel_cos(y[0], y[1]);
          default:
              return __kernel_sin(y[0], y[1], 1);
          }
      }
  }
  
  libm_hidden_def(cos)
  

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