Kernel FPU emulator, chain saw edition.

1 files changed, 95 insertions, 0 deletions

diff --git a/arch/mips/math-emu/sp_tint.c b/arch/mips/math-emu/sp_tint.c
new file mode 100644
index 000000000..eeb26551e
--- /dev/null
+++ b/arch/mips/math-emu/sp_tint.c
@@ -0,0 +1,95 @@
+/* IEEE754 floating point arithmetic
+ * single precision
+ */
+/*
+ * MIPS floating point support
+ * Copyright (C) 1994-2000 Algorithmics Ltd.  All rights reserved.
+ * 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 <limits.h>
+#ifdef __KERNEL__
+#define assert(expr) ((void)0)
+#else
+#include <assert.h>
+#endif
+#include <stdarg.h>
+
+#include "ieee754sp.h"
+
+int ieee754sp_tint(ieee754sp x)
+{
+	COMPXSP;
+
+	CLEARCX;
+
+	EXPLODEXSP;
+
+	switch (xc) {
+	case IEEE754_CLASS_SNAN:
+	case IEEE754_CLASS_QNAN:
+		SETCX(IEEE754_INVALID_OPERATION);
+		return ieee754si_xcpt(ieee754si_indef(), "fixsp", x);
+	case IEEE754_CLASS_INF:
+		SETCX(IEEE754_OVERFLOW);
+		return ieee754si_xcpt(ieee754si_indef(), "fixsp", x);
+	case IEEE754_CLASS_ZERO:
+		return 0;
+	case IEEE754_CLASS_DNORM:	/* much to small */
+		SETCX(IEEE754_UNDERFLOW);
+		return ieee754si_xcpt(0, "fixsp", x);
+	case IEEE754_CLASS_NORM:
+		break;
+	}
+	if (xe >= 31) {
+		SETCX(IEEE754_OVERFLOW);
+		return ieee754si_xcpt(ieee754si_indef(), "fix", x);
+	}
+	if (xe < 0) {
+		SETCX(IEEE754_UNDERFLOW);
+		return ieee754si_xcpt(0, "fix", x);
+	}
+	/* oh gawd */
+	if (xe > SP_MBITS) {
+		xm <<= xe - SP_MBITS;
+	} else if (xe < SP_MBITS) {
+		/* XXX no rounding 
+		 */
+		xm >>= SP_MBITS - xe;
+	}
+	if (xs)
+		return -xm;
+	else
+		return xm;
+}
+
+
+unsigned int ieee754sp_tuns(ieee754sp x)
+{
+	ieee754sp hb = ieee754sp_1e31();
+
+	/* what if x < 0 ?? */
+	if (ieee754sp_lt(x, hb))
+		return (unsigned) ieee754sp_tint(x);
+
+	return (unsigned) ieee754sp_tint(ieee754sp_sub(x, hb)) |
+	    ((unsigned) 1 << 31);
+}