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authorIan Moffett <ian@osmora.org>2024-03-07 17:28:00 -0500
committerIan Moffett <ian@osmora.org>2024-03-07 17:28:32 -0500
commitbd5969fc876a10b18613302db7087ef3c40f18e1 (patch)
tree7c2b8619afe902abf99570df2873fbdf40a4d1a1 /lib/mlibc/options/ansi/generic/complex/csqrtf.c
parenta95b38b1b92b172e6cc4e8e56a88a30cc65907b0 (diff)
lib: Add mlibc
Signed-off-by: Ian Moffett <ian@osmora.org>
Diffstat (limited to 'lib/mlibc/options/ansi/generic/complex/csqrtf.c')
-rw-r--r--lib/mlibc/options/ansi/generic/complex/csqrtf.c102
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;
+}