patch-2.4.6 linux/arch/mips64/math-emu/dp_tlong.c
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- Lines: 142
- Date:
Mon Jul 2 13:56:41 2001
- Orig file:
v2.4.5/linux/arch/mips64/math-emu/dp_tlong.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.4.5/linux/arch/mips64/math-emu/dp_tlong.c linux/arch/mips64/math-emu/dp_tlong.c
@@ -0,0 +1,141 @@
+/* IEEE754 floating point arithmetic
+ * double precision: common utilities
+ */
+/*
+ * 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 "ieee754dp.h"
+
+long long ieee754dp_tlong(ieee754dp x)
+{
+ COMPXDP;
+
+ CLEARCX;
+
+ EXPLODEXDP;
+
+ switch (xc) {
+ case IEEE754_CLASS_SNAN:
+ case IEEE754_CLASS_QNAN:
+ SETCX(IEEE754_INVALID_OPERATION);
+ return ieee754di_xcpt(ieee754di_indef(), "dp_tlong", x);
+ case IEEE754_CLASS_INF:
+ SETCX(IEEE754_OVERFLOW);
+ return ieee754di_xcpt(ieee754di_indef(), "dp_tlong", x);
+ case IEEE754_CLASS_ZERO:
+ return 0;
+ case IEEE754_CLASS_DNORM: /* much too small */
+ SETCX(IEEE754_UNDERFLOW);
+ return ieee754di_xcpt(0, "dp_tlong", x);
+ case IEEE754_CLASS_NORM:
+ break;
+ }
+ if (xe >= 63) {
+ SETCX(IEEE754_OVERFLOW);
+ return ieee754di_xcpt(ieee754di_indef(), "dp_tlong", x);
+ }
+ if (xe < 0) {
+ if (ieee754_csr.rm == IEEE754_RU) {
+ if (xs) { /* Negative */
+ return 0x0000000000000000LL;
+ } else { /* Positive */
+ return 0x0000000000000001LL;
+ }
+ } else if (ieee754_csr.rm == IEEE754_RD) {
+ if (xs) { /* Negative , return -1 */
+ return 0xffffffffffffffffLL;
+ } else { /* Positive */
+ return 0x0000000000000000LL;
+ }
+ } else {
+ SETCX(IEEE754_UNDERFLOW);
+ return ieee754di_xcpt(0, "dp_tlong", x);
+ }
+ }
+ /* oh gawd */
+ if (xe > DP_MBITS) {
+ xm <<= xe - DP_MBITS;
+ } else if (xe < DP_MBITS) {
+ unsigned long long residue;
+ unsigned long long mask = 0;
+ int i;
+ int round;
+ int sticky;
+ int odd;
+
+ /* compute mask */
+ for (i = 0; i < DP_MBITS - xe; i++) {
+ mask = mask << 1;
+ mask = mask | 0x1;
+ }
+ residue = (xm & mask) << (64 - (DP_MBITS - xe));
+ round =
+ ((0x8000000000000000LL & residue) !=
+ 0x0000000000000000LL);
+ sticky =
+ ((0x7fffffffffffffffLL & residue) !=
+ 0x0000000000000000LL);
+
+ xm >>= DP_MBITS - xe;
+
+ odd = ((xm & 0x1) != 0x0000000000000000LL);
+
+ /* Do the rounding */
+ if (!round && sticky) {
+ if ((ieee754_csr.rm == IEEE754_RU && !xs)
+ || (ieee754_csr.rm == IEEE754_RD && xs)) {
+ xm++;
+ }
+ } else if (round && !sticky) {
+ if ((ieee754_csr.rm == IEEE754_RU && !xs)
+ || (ieee754_csr.rm == IEEE754_RD && xs)
+ || (ieee754_csr.rm == IEEE754_RN && odd)) {
+ xm++;
+ }
+ } else if (round && sticky) {
+ if ((ieee754_csr.rm == IEEE754_RU && !xs)
+ || (ieee754_csr.rm == IEEE754_RD && xs)
+ || (ieee754_csr.rm == IEEE754_RN)) {
+ xm++;
+ }
+ }
+ }
+ if (xs)
+ return -xm;
+ else
+ return xm;
+}
+
+
+unsigned long long ieee754dp_tulong(ieee754dp x)
+{
+ ieee754dp hb = ieee754dp_1e63();
+
+ /* what if x < 0 ?? */
+ if (ieee754dp_lt(x, hb))
+ return (unsigned long long) ieee754dp_tlong(x);
+
+ return (unsigned long long) ieee754dp_tlong(ieee754dp_sub(x, hb)) |
+ (1ULL << 63);
+}
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