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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/mips/math-emu/dp_sub.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/mips/math-emu/dp_sub.c')
-rw-r--r--kernel/arch/mips/math-emu/dp_sub.c185
1 files changed, 185 insertions, 0 deletions
diff --git a/kernel/arch/mips/math-emu/dp_sub.c b/kernel/arch/mips/math-emu/dp_sub.c
new file mode 100644
index 000000000..fc17a781b
--- /dev/null
+++ b/kernel/arch/mips/math-emu/dp_sub.c
@@ -0,0 +1,185 @@
+/* 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_sub(union ieee754dp x, union ieee754dp y)
+{
+ int s;
+
+ 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):
+ if (xs != ys)
+ return x;
+ ieee754_setcx(IEEE754_INVALID_OPERATION);
+ return ieee754dp_indef();
+
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
+ return ieee754dp_inf(ys ^ 1);
+
+ 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 x;
+
+ /*
+ * Zero handling
+ */
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
+ if (xs != ys)
+ return x;
+ else
+ return ieee754dp_zero(ieee754_csr.rm == FPU_CSR_RD);
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
+ return x;
+
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
+ /* quick fix up */
+ DPSIGN(y) ^= 1;
+ return y;
+
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM):
+ DPDNORMX;
+ /* FALL THROUGH */
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM):
+ /* normalize ym,ye */
+ DPDNORMY;
+ break;
+
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_NORM):
+ /* normalize xm,xe */
+ DPDNORMX;
+ break;
+
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_NORM):
+ break;
+ }
+ /* flip sign of y and handle as add */
+ ys ^= 1;
+
+ assert(xm & DP_HIDDEN_BIT);
+ assert(ym & DP_HIDDEN_BIT);
+
+
+ /* provide guard,round and stick bit dpace */
+ xm <<= 3;
+ ym <<= 3;
+
+ if (xe > ye) {
+ /*
+ * Have to shift y fraction right to align
+ */
+ s = xe - ye;
+ ym = XDPSRS(ym, s);
+ ye += s;
+ } else if (ye > xe) {
+ /*
+ * Have to shift x fraction right to align
+ */
+ s = ye - xe;
+ xm = XDPSRS(xm, s);
+ xe += s;
+ }
+ assert(xe == ye);
+ assert(xe <= DP_EMAX);
+
+ if (xs == ys) {
+ /* generate 28 bit result of adding two 27 bit numbers
+ */
+ xm = xm + ym;
+
+ if (xm >> (DP_FBITS + 1 + 3)) { /* carry out */
+ xm = XDPSRS1(xm); /* shift preserving sticky */
+ xe++;
+ }
+ } else {
+ if (xm >= ym) {
+ xm = xm - ym;
+ } else {
+ xm = ym - xm;
+ xs = ys;
+ }
+ if (xm == 0) {
+ if (ieee754_csr.rm == FPU_CSR_RD)
+ return ieee754dp_zero(1); /* round negative inf. => sign = -1 */
+ else
+ return ieee754dp_zero(0); /* other round modes => sign = 1 */
+ }
+
+ /* normalize to rounding precision
+ */
+ while ((xm >> (DP_FBITS + 3)) == 0) {
+ xm <<= 1;
+ xe--;
+ }
+ }
+
+ return ieee754dp_format(xs, xe, xm);
+}