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-rw-r--r--arch/mips/math-emu/sp_modf.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/mips/math-emu/sp_modf.c b/arch/mips/math-emu/sp_modf.c
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index 0000000..4b1dbac
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+++ b/arch/mips/math-emu/sp_modf.c
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+/* IEEE754 floating point arithmetic
+ * single precision
+ */
+/*
+ * MIPS floating point support
+ * Copyright (C) 1994-2000 Algorithmics Ltd.
+ * http://www.algor.co.uk
+ *
+ * ########################################################################
+ *
+ * This program is free software; you can distribute it and/or modify it
+ * under the terms of the GNU General Public License (Version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * ########################################################################
+ */
+
+
+#include "ieee754sp.h"
+
+/* modf function is always exact for a finite number
+*/
+ieee754sp ieee754sp_modf(ieee754sp x, ieee754sp * ip)
+{
+ COMPXSP;
+
+ CLEARCX;
+
+ EXPLODEXSP;
+
+ switch (xc) {
+ case IEEE754_CLASS_SNAN:
+ case IEEE754_CLASS_QNAN:
+ case IEEE754_CLASS_INF:
+ case IEEE754_CLASS_ZERO:
+ *ip = x;
+ return x;
+ case IEEE754_CLASS_DNORM:
+ /* far to small */
+ *ip = ieee754sp_zero(xs);
+ return x;
+ case IEEE754_CLASS_NORM:
+ break;
+ }
+ if (xe < 0) {
+ *ip = ieee754sp_zero(xs);
+ return x;
+ }
+ if (xe >= SP_MBITS) {
+ *ip = x;
+ return ieee754sp_zero(xs);
+ }
+ /* generate ipart mantissa by clearing bottom bits
+ */
+ *ip = buildsp(xs, xe + SP_EBIAS,
+ ((xm >> (SP_MBITS - xe)) << (SP_MBITS - xe)) &
+ ~SP_HIDDEN_BIT);
+
+ /* generate fpart mantissa by clearing top bits
+ * and normalizing (must be able to normalize)
+ */
+ xm = (xm << (32 - (SP_MBITS - xe))) >> (32 - (SP_MBITS - xe));
+ if (xm == 0)
+ return ieee754sp_zero(xs);
+
+ while ((xm >> SP_MBITS) == 0) {
+ xm <<= 1;
+ xe--;
+ }
+ return buildsp(xs, xe + SP_EBIAS, xm & ~SP_HIDDEN_BIT);
+}
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