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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/mips/math-emu/dp_div.c
parentInitial commit. (diff)
downloadlinux-c109f8d9e922037b3fa45f46d78384d49db8ad76.tar.xz
linux-c109f8d9e922037b3fa45f46d78384d49db8ad76.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/mips/math-emu/dp_div.c')
-rw-r--r--arch/mips/math-emu/dp_div.c156
1 files changed, 156 insertions, 0 deletions
diff --git a/arch/mips/math-emu/dp_div.c b/arch/mips/math-emu/dp_div.c
new file mode 100644
index 000000000..3063ae3ab
--- /dev/null
+++ b/arch/mips/math-emu/dp_div.c
@@ -0,0 +1,156 @@
+/* IEEE754 floating point arithmetic
+ * double precision: common utilities
+ */
+/*
+ * 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 "ieee754dp.h"
+
+union ieee754dp ieee754dp_div(union ieee754dp x, union ieee754dp y)
+{
+ u64 rm;
+ int re;
+ u64 bm;
+
+ COMPXDP;
+ COMPYDP;
+
+ EXPLODEXDP;
+ EXPLODEYDP;
+
+ ieee754_clearcx();
+
+ FLUSHXDP;
+ FLUSHYDP;
+
+ 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 ieee754dp_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 ieee754dp_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_INF):
+ ieee754_setcx(IEEE754_INVALID_OPERATION);
+ return ieee754dp_indef();
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
+ return ieee754dp_zero(xs ^ ys);
+
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
+ return ieee754dp_inf(xs ^ ys);
+
+ /*
+ * Zero handling
+ */
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
+ ieee754_setcx(IEEE754_INVALID_OPERATION);
+ return ieee754dp_indef();
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
+ ieee754_setcx(IEEE754_ZERO_DIVIDE);
+ return ieee754dp_inf(xs ^ ys);
+
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
+ return ieee754dp_zero(xs == ys ? 0 : 1);
+
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
+ DPDNORMX;
+ /* fall through */
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
+ DPDNORMY;
+ break;
+
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
+ DPDNORMX;
+ break;
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_NORM):
+ break;
+ }
+ assert(xm & DP_HIDDEN_BIT);
+ assert(ym & DP_HIDDEN_BIT);
+
+ /* provide rounding space */
+ xm <<= 3;
+ ym <<= 3;
+
+ /* now the dirty work */
+
+ rm = 0;
+ re = xe - ye;
+
+ for (bm = DP_MBIT(DP_FBITS + 2); bm; bm >>= 1) {
+ if (xm >= ym) {
+ xm -= ym;
+ rm |= bm;
+ if (xm == 0)
+ break;
+ }
+ xm <<= 1;
+ }
+
+ rm <<= 1;
+ if (xm)
+ rm |= 1; /* have remainder, set sticky */
+
+ assert(rm);
+
+ /*
+ * Normalise rm to rounding precision ?
+ */
+ while ((rm >> (DP_FBITS + 3)) == 0) {
+ rm <<= 1;
+ re--;
+ }
+
+ return ieee754dp_format(xs == ys ? 0 : 1, re, rm);
+}