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-rw-r--r--arch/mips/math-emu/sp_mul.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/mips/math-emu/sp_mul.c b/arch/mips/math-emu/sp_mul.c
new file mode 100644
index 000000000..d910c43a6
--- /dev/null
+++ b/arch/mips/math-emu/sp_mul.c
@@ -0,0 +1,166 @@
+/* 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"
+
+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;
+
+ EXPLODEXSP;
+ EXPLODEYSP;
+
+ ieee754_clearcx();
+
+ FLUSHXSP;
+ FLUSHYSP;
+
+ switch (CLPAIR(xc, yc)) {
+ case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_SNAN):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_SNAN):
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_SNAN):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_SNAN):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_SNAN):
+ return ieee754sp_nanxcpt(y);
+
+ case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_SNAN):
+ case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_QNAN):
+ case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_DNORM):
+ case CLPAIR(IEEE754_CLASS_SNAN, IEEE754_CLASS_INF):
+ return ieee754sp_nanxcpt(x);
+
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_QNAN):
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_QNAN):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_QNAN):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_QNAN):
+ return y;
+
+ case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_QNAN):
+ case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_DNORM):
+ case CLPAIR(IEEE754_CLASS_QNAN, IEEE754_CLASS_INF):
+ return x;
+
+
+ /*
+ * Infinity handling
+ */
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
+ ieee754_setcx(IEEE754_INVALID_OPERATION);
+ return ieee754sp_indef();
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+ return ieee754sp_inf(xs ^ ys);
+
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
+ return ieee754sp_zero(xs ^ ys);
+
+
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
+ SPDNORMX;
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
+ SPDNORMY;
+ break;
+
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
+ SPDNORMX;
+ break;
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_NORM):
+ break;
+ }
+ /* rm = xm * ym, re = xe+ye basically */
+ assert(xm & SP_HIDDEN_BIT);
+ assert(ym & SP_HIDDEN_BIT);
+
+ 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);
+}