1 files changed, 105 insertions, 0 deletions
diff --git a/newlib/libm/mathfp/sf_asine.c b/newlib/libm/mathfp/sf_asine.c
new file mode 100644
index 00000000000..12ba28927d7
--- /dev/null
+++ b/newlib/libm/mathfp/sf_asine.c
@@ -0,0 +1,105 @@
+
+/* @(#)z_asinef.c 1.0 98/08/13 */
+/******************************************************************
+ * The following routines are coded directly from the algorithms
+ * and coefficients given in "Software Manual for the Elementary
+ * Functions" by William J. Cody, Jr. and William Waite, Prentice
+ * Hall, 1980.
+ ******************************************************************/
+/******************************************************************
+ * Arcsine
+ *
+ * Input:
+ *   x - floating point value
+ *   acosine - indicates acos calculation
+ *
+ * Output:
+ *   Arcsine of x.
+ *
+ * Description:
+ *   This routine calculates arcsine / arccosine.
+ *
+ *****************************************************************/
+
+#include "fdlibm.h"
+#include "zmath.h"
+
+static const float p[] = { 0.933935835, -0.504400557 };
+static const float q[] = { 0.560363004e+1, -0.554846723e+1 };
+static const float a[] = { 0.0, 0.785398163 };
+static const float b[] = { 1.570796326, 0.785398163 };
+
+float
+_DEFUN (asinef, (float, int),
+        float x _AND
+        int acosine)
+{
+  int flag, i;
+  int branch = 0;
+  float g, res, R, P, Q, y;
+
+  /* Check for special values. */
+  i = numtestf (x);
+  if (i == NAN || i == INF)
+    {
+      errno = EDOM;
+      if (i == NAN)
+        return (x);
+      else
+        return (z_infinity_f.f);
+    }
+
+  y = fabsf (x);
+  flag = acosine;
+
+  if (y > 0.5)
+    {
+      i = 1 - flag;
+
+      /* Check for range error. */
+      if (y > 1.0)
+        {
+          errno = ERANGE;
+          return (z_notanum_f.f);
+        }
+
+      g = (1 - y) / 2.0;
+      y = -2 * sqrt (g);
+      branch = 1;
+    }
+  else
+    {
+      i = flag;
+      if (y < z_rooteps_f)
+        res = y;
+      else
+        g = y * y;
+    }
+
+  if (y >= z_rooteps_f || branch == 1)
+    {
+      /* Calculate the Taylor series. */
+      P = (p[1] * g + p[0]) * g;
+      Q = (g + q[1]) * g + q[0];
+      R = P / Q;
+
+      res = y + y * R;
+    }
+
+  /* Calculate asine or acose. */
+  if (flag == 0)
+    {
+      res = (a[i] + res) + a[i];
+      if (x < 0.0)
+        res = -res;
+    }
+  else
+    {
+      if (x < 0.0)
+        res = (b[i] + res) + b[i];
+      else
+        res = (a[i] - res) + a[i];
+    }
+
+  return (res);
+}