summaryrefslogtreecommitdiffstats
path: root/kernel/arch/mips/math-emu/sp_fmax.c
diff options
context:
space:
mode:
authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/mips/math-emu/sp_fmax.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/mips/math-emu/sp_fmax.c')
-rw-r--r--kernel/arch/mips/math-emu/sp_fmax.c213
1 files changed, 213 insertions, 0 deletions
diff --git a/kernel/arch/mips/math-emu/sp_fmax.c b/kernel/arch/mips/math-emu/sp_fmax.c
new file mode 100644
index 000000000..4d000844e
--- /dev/null
+++ b/kernel/arch/mips/math-emu/sp_fmax.c
@@ -0,0 +1,213 @@
+/*
+ * IEEE754 floating point arithmetic
+ * single precision: MAX{,A}.f
+ * MAX : Scalar Floating-Point Maximum
+ * MAXA: Scalar Floating-Point argument with Maximum Absolute Value
+ *
+ * MAX.S : FPR[fd] = maxNum(FPR[fs],FPR[ft])
+ * MAXA.S: FPR[fd] = maxNumMag(FPR[fs],FPR[ft])
+ *
+ * MIPS floating point support
+ * Copyright (C) 2015 Imagination Technologies, Ltd.
+ * Author: Markos Chandras <markos.chandras@imgtec.com>
+ *
+ * This program is free software; you can distribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; version 2 of the License.
+ */
+
+#include "ieee754sp.h"
+
+union ieee754sp ieee754sp_fmax(union ieee754sp x, union ieee754sp y)
+{
+ COMPXSP;
+ COMPYSP;
+
+ EXPLODEXSP;
+ EXPLODEYSP;
+
+ FLUSHXSP;
+ FLUSHYSP;
+
+ ieee754_clearcx();
+
+ 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);
+
+ /* numbers are preferred to NaNs */
+ 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 x;
+
+ 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 y;
+
+ /*
+ * Infinity and zero handling
+ */
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
+ return xs ? y : x;
+
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
+ return ys ? x : y;
+
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
+ if (xs == ys)
+ return x;
+ return ieee754sp_zero(1);
+
+ 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;
+ }
+
+ /* Finally get to do some computation */
+
+ assert(xm & SP_HIDDEN_BIT);
+ assert(ym & SP_HIDDEN_BIT);
+
+ /* Compare signs */
+ if (xs > ys)
+ return y;
+ else if (xs < ys)
+ return x;
+
+ /* Compare exponent */
+ if (xe > ye)
+ return x;
+ else if (xe < ye)
+ return y;
+
+ /* Compare mantissa */
+ if (xm <= ym)
+ return y;
+ return x;
+}
+
+union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
+{
+ COMPXSP;
+ COMPYSP;
+
+ EXPLODEXSP;
+ EXPLODEYSP;
+
+ FLUSHXSP;
+ FLUSHYSP;
+
+ ieee754_clearcx();
+
+ 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);
+
+ /* numbers are preferred to NaNs */
+ 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 x;
+
+ 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 y;
+
+ /*
+ * Infinity and zero handling
+ */
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
+ return x;
+
+ case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_NORM):
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_DNORM):
+ return y;
+
+ case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO):
+ if (xs == ys)
+ return x;
+ return ieee754sp_zero(1);
+
+ 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;
+ }
+
+ /* Finally get to do some computation */
+
+ assert(xm & SP_HIDDEN_BIT);
+ assert(ym & SP_HIDDEN_BIT);
+
+ /* Compare exponent */
+ if (xe > ye)
+ return x;
+ else if (xe < ye)
+ return y;
+
+ /* Compare mantissa */
+ if (xm <= ym)
+ return y;
+ return x;
+}