File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/mips/math-emu/sp_tint.c b/arch/mips/math-emu/sp_tint.c
new file mode 100644
index 0000000..091299a
--- /dev/null
+++ b/arch/mips/math-emu/sp_tint.c
@@ -0,0 +1,109 @@
+/* IEEE754 floating point arithmetic
+ * single precision
+ */
+/*
+ * MIPS floating point support
+ * Copyright (C) 1994-2000 Algorithmics Ltd.
+ *
+ *  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.,
+ *  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA.
+ */
+
+#include "ieee754sp.h"
+
+int ieee754sp_tint(union ieee754sp x)
+{
+	u32 residue;
+	int round;
+	int sticky;
+	int odd;
+
+	COMPXSP;
+
+	ieee754_clearcx();
+
+	EXPLODEXSP;
+	FLUSHXSP;
+
+	switch (xc) {
+	case IEEE754_CLASS_SNAN:
+	case IEEE754_CLASS_QNAN:
+	case IEEE754_CLASS_INF:
+		ieee754_setcx(IEEE754_INVALID_OPERATION);
+		return ieee754si_indef();
+
+	case IEEE754_CLASS_ZERO:
+		return 0;
+
+	case IEEE754_CLASS_DNORM:
+	case IEEE754_CLASS_NORM:
+		break;
+	}
+	if (xe >= 31) {
+		/* look for valid corner case */
+		if (xe == 31 && xs && xm == SP_HIDDEN_BIT)
+			return -0x80000000;
+		/* Set invalid. We will only use overflow for floating
+		   point overflow */
+		ieee754_setcx(IEEE754_INVALID_OPERATION);
+		return ieee754si_indef();
+	}
+	/* oh gawd */
+	if (xe > SP_FBITS) {
+		xm <<= xe - SP_FBITS;
+	} else {
+		if (xe < -1) {
+			residue = xm;
+			round = 0;
+			sticky = residue != 0;
+			xm = 0;
+		} else {
+			/* Shifting a u32 32 times does not work,
+			* so we do it in two steps. Be aware that xe
+			* may be -1 */
+			residue = xm << (xe + 1);
+			residue <<= 31 - SP_FBITS;
+			round = (residue >> 31) != 0;
+			sticky = (residue << 1) != 0;
+			xm >>= SP_FBITS - xe;
+		}
+		odd = (xm & 0x1) != 0x0;
+		switch (ieee754_csr.rm) {
+		case FPU_CSR_RN:
+			if (round && (sticky || odd))
+				xm++;
+			break;
+		case FPU_CSR_RZ:
+			break;
+		case FPU_CSR_RU:	/* toward +Infinity */
+			if ((round || sticky) && !xs)
+				xm++;
+			break;
+		case FPU_CSR_RD:	/* toward -Infinity */
+			if ((round || sticky) && xs)
+				xm++;
+			break;
+		}
+		if ((xm >> 31) != 0) {
+			/* This can happen after rounding */
+			ieee754_setcx(IEEE754_INVALID_OPERATION);
+			return ieee754si_indef();
+		}
+		if (round || sticky)
+			ieee754_setcx(IEEE754_INEXACT);
+	}
+	if (xs)
+		return -xm;
+	else
+		return xm;
+}