extend cmath (some of the functions are dummy)

[libm] / src / cmath / ccoshf.c

diff --git a/src/cmath/ccoshf.c b/src/cmath/ccoshf.c
new file mode 100644 (file)
index 0000000..683e77f
--- /dev/null
+++ b/src/cmath/ccoshf.c
@@ -0,0 +1,90 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/s_ccoshf.c */
+/*-
+ * Copyright (c) 2005 Bruce D. Evans and Steven G. Kargl
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice unmodified, this list of conditions, and the following
+ *    disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+/*
+ * Hyperbolic cosine of a complex argument.  See s_ccosh.c for details.
+ */
+
+#include "libm.h"
+
+static const float huge = 0x1p127;
+
+float complex ccoshf(float complex z)
+{
+       float x, y, h;
+       int32_t hx, hy, ix, iy;
+
+       x = crealf(z);
+       y = cimagf(z);
+
+       GET_FLOAT_WORD(hx, x);
+       GET_FLOAT_WORD(hy, y);
+
+       ix = 0x7fffffff & hx;
+       iy = 0x7fffffff & hy;
+
+       if (ix < 0x7f800000 && iy < 0x7f800000) {
+               if (iy == 0)
+                       return cpackf(coshf(x), x * y);
+               if (ix < 0x41100000)    /* small x: normal case */
+                       return cpackf(coshf(x) * cosf(y), sinhf(x) * sinf(y));
+
+               /* |x| >= 9, so cosh(x) ~= exp(|x|) */
+               if (ix < 0x42b17218) {
+                       /* x < 88.7: expf(|x|) won't overflow */
+                       h = expf(fabsf(x)) * 0.5f;
+                       return cpackf(h * cosf(y), copysignf(h, x) * sinf(y));
+               } else if (ix < 0x4340b1e7) {
+                       /* x < 192.7: scale to avoid overflow */
+                       z = __ldexp_cexpf(cpackf(fabsf(x), y), -1);
+                       return cpackf(crealf(z), cimagf(z) * copysignf(1, x));
+               } else {
+                       /* x >= 192.7: the result always overflows */
+                       h = huge * x;
+                       return cpackf(h * h * cosf(y), h * sinf(y));
+               }
+       }
+
+       if (ix == 0 && iy >= 0x7f800000)
+               return cpackf(y - y, copysignf(0, x * (y - y)));
+
+       if (iy == 0 && ix >= 0x7f800000) {
+               if ((hx & 0x7fffff) == 0)
+                       return cpackf(x * x, copysignf(0, x) * y);
+               return cpackf(x * x, copysignf(0, (x + x) * y));
+       }
+
+       if (ix < 0x7f800000 && iy >= 0x7f800000)
+               return cpackf(y - y, x * (y - y));
+
+       if (ix >= 0x7f800000 && (hx & 0x7fffff) == 0) {
+               if (iy >= 0x7f800000)
+                       return cpackf(x * x, x * (y - y));
+               return cpackf((x * x) * cosf(y), x * sinf(y));
+       }
+
+       return cpackf((x * x) * (y - y), (x + x) * (y - y));
+}