v4.19.13 snapshot.
diff --git a/arch/mips/math-emu/ieee754sp.c b/arch/mips/math-emu/ieee754sp.c
new file mode 100644
index 0000000..8423e4c
--- /dev/null
+++ b/arch/mips/math-emu/ieee754sp.c
@@ -0,0 +1,208 @@
+/* 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 <linux/compiler.h>
+
+#include "ieee754sp.h"
+
+int ieee754sp_class(union ieee754sp x)
+{
+ COMPXSP;
+ EXPLODEXSP;
+ return xc;
+}
+
+static inline int ieee754sp_isnan(union ieee754sp x)
+{
+ return ieee754_class_nan(ieee754sp_class(x));
+}
+
+static inline int ieee754sp_issnan(union ieee754sp x)
+{
+ int qbit;
+
+ assert(ieee754sp_isnan(x));
+ qbit = (SPMANT(x) & SP_MBIT(SP_FBITS - 1)) == SP_MBIT(SP_FBITS - 1);
+ return ieee754_csr.nan2008 ^ qbit;
+}
+
+
+/*
+ * Raise the Invalid Operation IEEE 754 exception
+ * and convert the signaling NaN supplied to a quiet NaN.
+ */
+union ieee754sp __cold ieee754sp_nanxcpt(union ieee754sp r)
+{
+ assert(ieee754sp_issnan(r));
+
+ ieee754_setcx(IEEE754_INVALID_OPERATION);
+ if (ieee754_csr.nan2008) {
+ SPMANT(r) |= SP_MBIT(SP_FBITS - 1);
+ } else {
+ SPMANT(r) &= ~SP_MBIT(SP_FBITS - 1);
+ if (!ieee754sp_isnan(r))
+ SPMANT(r) |= SP_MBIT(SP_FBITS - 2);
+ }
+
+ return r;
+}
+
+static unsigned int ieee754sp_get_rounding(int sn, unsigned int xm)
+{
+ /* inexact must round of 3 bits
+ */
+ if (xm & (SP_MBIT(3) - 1)) {
+ switch (ieee754_csr.rm) {
+ case FPU_CSR_RZ:
+ break;
+ case FPU_CSR_RN:
+ xm += 0x3 + ((xm >> 3) & 1);
+ /* xm += (xm&0x8)?0x4:0x3 */
+ break;
+ case FPU_CSR_RU: /* toward +Infinity */
+ if (!sn) /* ?? */
+ xm += 0x8;
+ break;
+ case FPU_CSR_RD: /* toward -Infinity */
+ if (sn) /* ?? */
+ xm += 0x8;
+ break;
+ }
+ }
+ return xm;
+}
+
+
+/* generate a normal/denormal number with over,under handling
+ * sn is sign
+ * xe is an unbiased exponent
+ * xm is 3bit extended precision value.
+ */
+union ieee754sp ieee754sp_format(int sn, int xe, unsigned int xm)
+{
+ assert(xm); /* we don't gen exact zeros (probably should) */
+
+ assert((xm >> (SP_FBITS + 1 + 3)) == 0); /* no excess */
+ assert(xm & (SP_HIDDEN_BIT << 3));
+
+ if (xe < SP_EMIN) {
+ /* strip lower bits */
+ int es = SP_EMIN - xe;
+
+ if (ieee754_csr.nod) {
+ ieee754_setcx(IEEE754_UNDERFLOW);
+ ieee754_setcx(IEEE754_INEXACT);
+
+ switch(ieee754_csr.rm) {
+ case FPU_CSR_RN:
+ case FPU_CSR_RZ:
+ return ieee754sp_zero(sn);
+ case FPU_CSR_RU: /* toward +Infinity */
+ if (sn == 0)
+ return ieee754sp_min(0);
+ else
+ return ieee754sp_zero(1);
+ case FPU_CSR_RD: /* toward -Infinity */
+ if (sn == 0)
+ return ieee754sp_zero(0);
+ else
+ return ieee754sp_min(1);
+ }
+ }
+
+ if (xe == SP_EMIN - 1 &&
+ ieee754sp_get_rounding(sn, xm) >> (SP_FBITS + 1 + 3))
+ {
+ /* Not tiny after rounding */
+ ieee754_setcx(IEEE754_INEXACT);
+ xm = ieee754sp_get_rounding(sn, xm);
+ xm >>= 1;
+ /* Clear grs bits */
+ xm &= ~(SP_MBIT(3) - 1);
+ xe++;
+ } else {
+ /* sticky right shift es bits
+ */
+ xm = XSPSRS(xm, es);
+ xe += es;
+ assert((xm & (SP_HIDDEN_BIT << 3)) == 0);
+ assert(xe == SP_EMIN);
+ }
+ }
+ if (xm & (SP_MBIT(3) - 1)) {
+ ieee754_setcx(IEEE754_INEXACT);
+ if ((xm & (SP_HIDDEN_BIT << 3)) == 0) {
+ ieee754_setcx(IEEE754_UNDERFLOW);
+ }
+
+ /* inexact must round of 3 bits
+ */
+ xm = ieee754sp_get_rounding(sn, xm);
+ /* adjust exponent for rounding add overflowing
+ */
+ if (xm >> (SP_FBITS + 1 + 3)) {
+ /* add causes mantissa overflow */
+ xm >>= 1;
+ xe++;
+ }
+ }
+ /* strip grs bits */
+ xm >>= 3;
+
+ assert((xm >> (SP_FBITS + 1)) == 0); /* no excess */
+ assert(xe >= SP_EMIN);
+
+ if (xe > SP_EMAX) {
+ ieee754_setcx(IEEE754_OVERFLOW);
+ ieee754_setcx(IEEE754_INEXACT);
+ /* -O can be table indexed by (rm,sn) */
+ switch (ieee754_csr.rm) {
+ case FPU_CSR_RN:
+ return ieee754sp_inf(sn);
+ case FPU_CSR_RZ:
+ return ieee754sp_max(sn);
+ case FPU_CSR_RU: /* toward +Infinity */
+ if (sn == 0)
+ return ieee754sp_inf(0);
+ else
+ return ieee754sp_max(1);
+ case FPU_CSR_RD: /* toward -Infinity */
+ if (sn == 0)
+ return ieee754sp_max(0);
+ else
+ return ieee754sp_inf(1);
+ }
+ }
+ /* gen norm/denorm/zero */
+
+ if ((xm & SP_HIDDEN_BIT) == 0) {
+ /* we underflow (tiny/zero) */
+ assert(xe == SP_EMIN);
+ if (ieee754_csr.mx & IEEE754_UNDERFLOW)
+ ieee754_setcx(IEEE754_UNDERFLOW);
+ return buildsp(sn, SP_EMIN - 1 + SP_EBIAS, xm);
+ } else {
+ assert((xm >> (SP_FBITS + 1)) == 0); /* no excess */
+ assert(xm & SP_HIDDEN_BIT);
+
+ return buildsp(sn, xe + SP_EBIAS, xm & ~SP_HIDDEN_BIT);
+ }
+}