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-rw-r--r--src/math/k_cosf.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/src/math/k_cosf.c b/src/math/k_cosf.c
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--- /dev/null
+++ b/src/math/k_cosf.c
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+/* k_cosf.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 <math.h>
+#include "math_private.h"
+
+static const float
+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 */
+
+float
+__kernel_cosf(float x, float y)
+{
+ 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));
+ }
+}