altos: Add floating point math functions from newlib

[fw/altos] / src / math / kf_cos.c

diff --git a/src/math/kf_cos.c b/src/math/kf_cos.c
new file mode 100644 (file)
index 0000000..4f71af2
--- /dev/null
+++ b/src/math/kf_cos.c
@@ -0,0 +1,59 @@
+/* kf_cos.c -- float version of k_cos.c
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+#include "fdlibm.h"
+
+#ifdef __STDC__
+static const float 
+#else
+static float 
+#endif
+one =  1.0000000000e+00, /* 0x3f800000 */
+C1  =  4.1666667908e-02, /* 0x3d2aaaab */
+C2  = -1.3888889225e-03, /* 0xbab60b61 */
+C3  =  2.4801587642e-05, /* 0x37d00d01 */
+C4  = -2.7557314297e-07, /* 0xb493f27c */
+C5  =  2.0875723372e-09, /* 0x310f74f6 */
+C6  = -1.1359647598e-11; /* 0xad47d74e */
+
+#ifdef __STDC__
+       float __kernel_cosf(float x, float y)
+#else
+       float __kernel_cosf(x, y)
+       float x,y;
+#endif
+{
+       float a,hz,z,r,qx;
+       __int32_t ix;
+       GET_FLOAT_WORD(ix,x);
+       ix &= 0x7fffffff;                       /* ix = |x|'s high word*/
+       if(ix<0x32000000) {                     /* if x < 2**27 */
+           if(((int)x)==0) return one;         /* generate inexact */
+       }
+       z  = x*x;
+       r  = z*(C1+z*(C2+z*(C3+z*(C4+z*(C5+z*C6)))));
+       if(ix < 0x3e99999a)                     /* if |x| < 0.3 */ 
+           return one - ((float)0.5*z - (z*r - x*y));
+       else {
+           if(ix > 0x3f480000) {               /* x > 0.78125 */
+               qx = (float)0.28125;
+           } else {
+               SET_FLOAT_WORD(qx,ix-0x01000000);       /* x/4 */
+           }
+           hz = (float)0.5*z-qx;
+           a  = one-qx;
+           return a - (hz - (z*r-x*y));
+       }
+}