1 files changed, 102 insertions, 0 deletions
diff --git a/lib/mlibc/options/ansi/generic/complex/csqrtf.c b/lib/mlibc/options/ansi/generic/complex/csqrtf.c
new file mode 100644
index 0000000..13451fa
--- /dev/null
+++ b/lib/mlibc/options/ansi/generic/complex/csqrtf.c
@@ -0,0 +1,102 @@
+/* $NetBSD: csqrtf.c,v 1.1 2007/08/20 16:01:37 drochner Exp $ */
+
+/*-
+ * Copyright (c) 2007 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software written by Stephen L. Moshier.
+ * It is redistributed by the NetBSD Foundation by permission of the author.
+ *
+ * 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, 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``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 FOUNDATION OR CONTRIBUTORS
+ * 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.
+ *
+ * imported and modified include for newlib 2010/10/03 
+ * Marco Atzeri <marco_atzeri@yahoo.it>
+ */
+
+#include <complex.h>
+#include <math.h>
+
+float complex
+csqrtf(float complex z)
+{
+	float complex w;
+	float x, y, r, t, scale;
+
+	x = crealf (z);
+	y = cimagf (z);
+
+	if (y == 0.0f) {
+		if (x < 0.0f) {
+			w = 0.0f + sqrtf(-x) * I;
+			return w;
+		} else if (x == 0.0f) {
+			return (0.0f + y * I);
+		} else {
+			w = sqrtf(x) + y * I;
+			return w;
+		}
+	}
+
+	if (x == 0.0f) {
+		r = fabsf(y);
+		r = sqrtf(0.5f * r);
+		if (y > 0)
+			w = r + r * I;
+		else
+			w = r - r * I;
+		return w;
+	}
+
+	/* Rescale to avoid internal overflow or underflow.  */
+	if ((fabsf(x) > 4.0f) || (fabsf(y) > 4.0f)) {
+		x *= 0.25f;
+		y *= 0.25f;
+		scale = 2.0f;
+	} else {
+#if 1
+		x *= 6.7108864e7f; /* 2^26 */
+		y *= 6.7108864e7f;
+		scale = 1.220703125e-4f; /* 2^-13 */
+#else
+		x *= 4.0f;
+		y *= 4.0f;
+		scale = 0.5f;
+#endif
+	}
+	w = x + y * I;
+	r = cabsf(w);
+	if( x > 0 ) {
+		t = sqrtf(0.5f * r + 0.5f * x);
+		r = scale * fabsf((0.5f * y) / t);
+		t *= scale;
+	} else {
+		r = sqrtf(0.5f * r - 0.5f * x);
+		t = scale * fabsf((0.5f * y) / r);
+		r *= scale;
+	}
+
+	if (y < 0)
+		w = t - r * I;
+	else
+		w = t + r * I;
+	return w;
+}