Add a "fork" of musl as //fusl.

fusl/src/complex/csinhf.c

+/* origin: FreeBSD /usr/src/lib/msun/src/s_csinhf.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 sine of a complex argument z.  See s_csinh.c for details.
+ */
+
+#include "libm.h"
+
+static const float huge = 0x1p127;
+
+float complex csinhf(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 CMPLXF(sinhf(x), y);
+                if (ix < 0x41100000)    /* small x: normal case */
+                        return CMPLXF(sinhf(x) * cosf(y), coshf(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 CMPLXF(copysignf(h, x) * cosf(y), h * sinf(y));
+                } else if (ix < 0x4340b1e7) {
+                        /* x < 192.7: scale to avoid overflow */
+                        z = __ldexp_cexpf(CMPLXF(fabsf(x), y), -1);
+                        return CMPLXF(crealf(z) * copysignf(1, x), cimagf(z));
+                } else {
+                        /* x >= 192.7: the result always overflows */
+                        h = huge * x;
+                        return CMPLXF(h * cosf(y), h * h * sinf(y));
+                }
+        }
+
+        if (ix == 0 && iy >= 0x7f800000)
+                return CMPLXF(copysignf(0, x * (y - y)), y - y);
+
+        if (iy == 0 && ix >= 0x7f800000) {
+                if ((hx & 0x7fffff) == 0)
+                        return CMPLXF(x, y);
+                return CMPLXF(x, copysignf(0, y));
+        }
+
+        if (ix < 0x7f800000 && iy >= 0x7f800000)
+                return CMPLXF(y - y, x * (y - y));
+
+        if (ix >= 0x7f800000 && (hx & 0x7fffff) == 0) {
+                if (iy >= 0x7f800000)
+                        return CMPLXF(x * x, x * (y - y));
+                return CMPLXF(x * cosf(y), INFINITY * sinf(y));
+        }
+
+        return CMPLXF((x * x) * (y - y), (x + x) * (y - y));
+}