aboutsummaryrefslogtreecommitdiff
path: root/arch/mips/math-emu/dp_mul.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/math-emu/dp_mul.c')
-rw-r--r--arch/mips/math-emu/dp_mul.c143
1 files changed, 70 insertions, 73 deletions
diff --git a/arch/mips/math-emu/dp_mul.c b/arch/mips/math-emu/dp_mul.c
index 09175f46192..d3acdedb5b9 100644
--- a/arch/mips/math-emu/dp_mul.c
+++ b/arch/mips/math-emu/dp_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.
@@ -18,23 +16,32 @@
*
* 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 "ieee754dp.h"
-ieee754dp ieee754dp_mul(ieee754dp x, ieee754dp y)
+union ieee754dp ieee754dp_mul(union ieee754dp x, union ieee754dp y)
{
+ int re;
+ int rs;
+ u64 rm;
+ unsigned lxm;
+ unsigned hxm;
+ unsigned lym;
+ unsigned hym;
+ u64 lrm;
+ u64 hrm;
+ u64 t;
+ u64 at;
+
COMPXDP;
COMPYDP;
EXPLODEXDP;
EXPLODEYDP;
- CLEARCX;
+ ieee754_clearcx();
FLUSHXDP;
FLUSHYDP;
@@ -51,8 +58,8 @@ ieee754dp ieee754dp_mul(ieee754dp x, ieee754dp y)
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
- SETCX(IEEE754_INVALID_OPERATION);
- return ieee754dp_nanxcpt(ieee754dp_indef(), "mul", x, y);
+ ieee754_setcx(IEEE754_INVALID_OPERATION);
+ return ieee754dp_nanxcpt(ieee754dp_indef());
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
@@ -68,12 +75,13 @@ ieee754dp ieee754dp_mul(ieee754dp x, ieee754dp y)
return x;
- /* Infinity handling */
-
+ /*
+ * Infinity handling
+ */
case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
- SETCX(IEEE754_INVALID_OPERATION);
- return ieee754dp_xcpt(ieee754dp_indef(), "mul", x, y);
+ ieee754_setcx(IEEE754_INVALID_OPERATION);
+ return ieee754dp_indef();
case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
@@ -107,70 +115,59 @@ ieee754dp ieee754dp_mul(ieee754dp x, ieee754dp y)
/* rm = xm * ym, re = xe+ye basically */
assert(xm & DP_HIDDEN_BIT);
assert(ym & DP_HIDDEN_BIT);
- {
- int re = xe + ye;
- int rs = xs ^ ys;
- u64 rm;
- /* shunt to top of word */
- xm <<= 64 - (DP_MBITS + 1);
- ym <<= 64 - (DP_MBITS + 1);
+ re = xe + ye;
+ rs = xs ^ ys;
+
+ /* shunt to top of word */
+ xm <<= 64 - (DP_FBITS + 1);
+ ym <<= 64 - (DP_FBITS + 1);
- /* multiply 32bits xm,ym to give high 32bits rm with stickness
- */
+ /*
+ * Multiply 32 bits xm, ym to give high 32 bits rm with stickness.
+ */
- /* 32 * 32 => 64 */
+ /* 32 * 32 => 64 */
#define DPXMULT(x, y) ((u64)(x) * (u64)y)
- {
- unsigned lxm = xm;
- unsigned hxm = xm >> 32;
- unsigned lym = ym;
- unsigned hym = ym >> 32;
- u64 lrm;
- u64 hrm;
-
- lrm = DPXMULT(lxm, lym);
- hrm = DPXMULT(hxm, hym);
-
- {
- u64 t = DPXMULT(lxm, hym);
- {
- u64 at =
- lrm + (t << 32);
- hrm += at < lrm;
- lrm = at;
- }
- hrm = hrm + (t >> 32);
- }
-
- {
- u64 t = DPXMULT(hxm, lym);
- {
- u64 at =
- lrm + (t << 32);
- hrm += at < lrm;
- lrm = at;
- }
- hrm = hrm + (t >> 32);
- }
- rm = hrm | (lrm != 0);
- }
-
- /*
- * sticky shift down to normal rounding precision
- */
- if ((s64) rm < 0) {
- rm =
- (rm >> (64 - (DP_MBITS + 1 + 3))) |
- ((rm << (DP_MBITS + 1 + 3)) != 0);
+ lxm = xm;
+ hxm = xm >> 32;
+ lym = ym;
+ hym = ym >> 32;
+
+ lrm = DPXMULT(lxm, lym);
+ hrm = DPXMULT(hxm, hym);
+
+ t = DPXMULT(lxm, hym);
+
+ at = lrm + (t << 32);
+ hrm += at < lrm;
+ lrm = at;
+
+ hrm = hrm + (t >> 32);
+
+ t = DPXMULT(hxm, lym);
+
+ at = lrm + (t << 32);
+ hrm += at < lrm;
+ lrm = at;
+
+ hrm = hrm + (t >> 32);
+
+ rm = hrm | (lrm != 0);
+
+ /*
+ * Sticky shift down to normal rounding precision.
+ */
+ if ((s64) rm < 0) {
+ rm = (rm >> (64 - (DP_FBITS + 1 + 3))) |
+ ((rm << (DP_FBITS + 1 + 3)) != 0);
re++;
- } else {
- rm =
- (rm >> (64 - (DP_MBITS + 1 + 3 + 1))) |
- ((rm << (DP_MBITS + 1 + 3 + 1)) != 0);
- }
- assert(rm & (DP_HIDDEN_BIT << 3));
- DPNORMRET2(rs, re, rm, "mul", x, y);
+ } else {
+ rm = (rm >> (64 - (DP_FBITS + 1 + 3 + 1))) |
+ ((rm << (DP_FBITS + 1 + 3 + 1)) != 0);
}
+ assert(rm & (DP_HIDDEN_BIT << 3));
+
+ return ieee754dp_format(rs, re, rm);
}