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Diffstat (limited to 'arch/mips/math-emu/sp_mul.c')
-rw-r--r--arch/mips/math-emu/sp_mul.c127
1 files changed, 61 insertions, 66 deletions
diff --git a/arch/mips/math-emu/sp_mul.c b/arch/mips/math-emu/sp_mul.c
index 0e19d0edd3f9..890c13a2965e 100644
--- a/arch/mips/math-emu/sp_mul.c
+++ b/arch/mips/math-emu/sp_mul.c
@@ -5,8 +5,6 @@
* 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.
@@ -18,16 +16,25 @@
*
* 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.
- *
- * ########################################################################
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-
#include "ieee754sp.h"
union ieee754sp ieee754sp_mul(union ieee754sp x, union ieee754sp y)
{
+ int re;
+ int rs;
+ unsigned rm;
+ unsigned short lxm;
+ unsigned short hxm;
+ unsigned short lym;
+ unsigned short hym;
+ unsigned lrm;
+ unsigned hrm;
+ unsigned t;
+ unsigned at;
+
COMPXSP;
COMPYSP;
@@ -68,8 +75,9 @@ union ieee754sp ieee754sp_mul(union ieee754sp x, union ieee754sp y)
return x;
- /* Infinity handling */
-
+ /*
+ * Infinity handling
+ */
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
ieee754_setcx(IEEE754_INVALID_OPERATION);
@@ -108,63 +116,50 @@ union ieee754sp ieee754sp_mul(union ieee754sp x, union ieee754sp y)
assert(xm & SP_HIDDEN_BIT);
assert(ym & SP_HIDDEN_BIT);
- {
- int re = xe + ye;
- int rs = xs ^ ys;
- unsigned rm;
-
- /* shunt to top of word */
- xm <<= 32 - (SP_FBITS + 1);
- ym <<= 32 - (SP_FBITS + 1);
-
- /* multiply 32bits xm,ym to give high 32bits rm with stickness
- */
- {
- unsigned short lxm = xm & 0xffff;
- unsigned short hxm = xm >> 16;
- unsigned short lym = ym & 0xffff;
- unsigned short hym = ym >> 16;
- unsigned lrm;
- unsigned hrm;
-
- lrm = lxm * lym; /* 16 * 16 => 32 */
- hrm = hxm * hym; /* 16 * 16 => 32 */
-
- {
- unsigned t = lxm * hym; /* 16 * 16 => 32 */
- {
- unsigned at = lrm + (t << 16);
- hrm += at < lrm;
- lrm = at;
- }
- hrm = hrm + (t >> 16);
- }
-
- {
- unsigned t = hxm * lym; /* 16 * 16 => 32 */
- {
- unsigned at = lrm + (t << 16);
- hrm += at < lrm;
- lrm = at;
- }
- hrm = hrm + (t >> 16);
- }
- rm = hrm | (lrm != 0);
- }
-
- /*
- * sticky shift down to normal rounding precision
- */
- if ((int) rm < 0) {
- rm = (rm >> (32 - (SP_FBITS + 1 + 3))) |
- ((rm << (SP_FBITS + 1 + 3)) != 0);
- re++;
- } else {
- rm = (rm >> (32 - (SP_FBITS + 1 + 3 + 1))) |
- ((rm << (SP_FBITS + 1 + 3 + 1)) != 0);
- }
- assert(rm & (SP_HIDDEN_BIT << 3));
-
- return ieee754sp_format(rs, re, rm);
+ re = xe + ye;
+ rs = xs ^ ys;
+
+ /* shunt to top of word */
+ xm <<= 32 - (SP_FBITS + 1);
+ ym <<= 32 - (SP_FBITS + 1);
+
+ /*
+ * Multiply 32 bits xm, ym to give high 32 bits rm with stickness.
+ */
+ lxm = xm & 0xffff;
+ hxm = xm >> 16;
+ lym = ym & 0xffff;
+ hym = ym >> 16;
+
+ lrm = lxm * lym; /* 16 * 16 => 32 */
+ hrm = hxm * hym; /* 16 * 16 => 32 */
+
+ t = lxm * hym; /* 16 * 16 => 32 */
+ at = lrm + (t << 16);
+ hrm += at < lrm;
+ lrm = at;
+ hrm = hrm + (t >> 16);
+
+ t = hxm * lym; /* 16 * 16 => 32 */
+ at = lrm + (t << 16);
+ hrm += at < lrm;
+ lrm = at;
+ hrm = hrm + (t >> 16);
+
+ rm = hrm | (lrm != 0);
+
+ /*
+ * Sticky shift down to normal rounding precision.
+ */
+ if ((int) rm < 0) {
+ rm = (rm >> (32 - (SP_FBITS + 1 + 3))) |
+ ((rm << (SP_FBITS + 1 + 3)) != 0);
+ re++;
+ } else {
+ rm = (rm >> (32 - (SP_FBITS + 1 + 3 + 1))) |
+ ((rm << (SP_FBITS + 1 + 3 + 1)) != 0);
}
+ assert(rm & (SP_HIDDEN_BIT << 3));
+
+ return ieee754sp_format(rs, re, rm);
}