1 files changed, 176 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/R/fmodf.c b/usr/src/lib/libm/common/R/fmodf.c
new file mode 100644
index 0000000000..d19bb3f2f8
--- /dev/null
+++ b/usr/src/lib/libm/common/R/fmodf.c
@@ -0,0 +1,176 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
+ */
+/*
+ * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma weak fmodf = __fmodf
+
+#include "libm.h"
+
+/* INDENT OFF */
+static const int
+	is = (int)0x80000000,
+	im = 0x007fffff,
+	ii = 0x7f800000,
+	iu = 0x00800000;
+/* INDENT ON */
+
+static const float zero	= 0.0;
+
+float
+fmodf(float x, float y) {
+	float	w;
+	int	hx, ix, iy, iz, k, ny, nd;
+
+	hx = *(int *)&x;
+	ix = hx & 0x7fffffff;
+	iy = *(int *)&y & 0x7fffffff;
+
+	/* purge off exception values */
+	if (ix >= ii || iy > ii || iy == 0) {
+		w = x * y;
+		w = w / w;
+	} else if (ix <= iy) {
+		if (ix < iy)
+			w = x;	/* return x if |x|<|y| */
+		else
+			w = zero * x;	/* return sign(x)*0.0 */
+	} else {
+		/* INDENT OFF */
+		/*
+		 * scale x,y to "normal" with
+		 *	ny = exponent of y
+		 *	nd = exponent of x minus exponent of y
+		 */
+		/* INDENT ON */
+		ny = iy >> 23;
+		k = ix >> 23;
+
+		/* special case for subnormal y or x */
+		if (ny == 0) {
+			ny = 1;
+			while (iy < iu) {
+				ny -= 1;
+				iy += iy;
+			}
+			nd = k - ny;
+			if (k == 0) {
+				nd += 1;
+				while (ix < iu) {
+					nd -= 1;
+					ix += ix;
+				}
+			} else {
+				ix = iu | (ix & im);
+			}
+		} else {
+			nd = k - ny;
+			ix = iu | (ix & im);
+			iy = iu | (iy & im);
+		}
+
+		/* fix point fmod for normalized ix and iy */
+		/* INDENT OFF */
+		/*
+		 * while (nd--) {
+		 * 	iz = ix - iy;
+		 * if (iz < 0)
+		 *	ix = ix + ix;
+		 * else if (iz == 0) {
+		 *	*(int *) &w = is & hx;
+		 *	return w;
+		 * }
+		 * else
+		 *	ix = iz + iz;
+		 * }
+		 */
+		/* INDENT ON */
+		/* unroll the above loop 4 times to gain performance */
+		k = nd >> 2;
+		nd -= k << 2;
+		while (k--) {
+			iz = ix - iy;
+			if (iz >= 0)
+				ix = iz + iz;
+			else
+				ix += ix;
+			iz = ix - iy;
+			if (iz >= 0)
+				ix = iz + iz;
+			else
+				ix += ix;
+			iz = ix - iy;
+			if (iz >= 0)
+				ix = iz + iz;
+			else
+				ix += ix;
+			iz = ix - iy;
+			if (iz >= 0)
+				ix = iz + iz;
+			else
+				ix += ix;
+			if (iz == 0) {
+				*(int *)&w = is & hx;
+				return (w);
+			}
+		}
+		while (nd--) {
+			iz = ix - iy;
+			if (iz >= 0)
+				ix = iz + iz;
+			else
+				ix += ix;
+		}
+		/* end of unrolling */
+
+		iz = ix - iy;
+		if (iz >= 0)
+			ix = iz;
+
+		/* convert back to floating value and restore the sign */
+		if (ix == 0) {
+			*(int *)&w = is & hx;
+			return (w);
+		}
+		while (ix < iu) {
+			ix += ix;
+			ny -= 1;
+		}
+		while (ix > (iu + iu)) {
+			ny += 1;
+			ix >>= 1;
+		}
+		if (ny > 0) {
+			*(int *)&w = (is & hx) | (ix & im) | (ny << 23);
+		} else {
+			/* subnormal output */
+			k = -ny + 1;
+			ix >>= k;
+			*(int *)&w = (is & hx) | ix;
+		}
+	}
+	return (w);
+}