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-rw-r--r--arch/mips/math-emu/ieee754sp.c165
1 files changed, 59 insertions, 106 deletions
diff --git a/arch/mips/math-emu/ieee754sp.c b/arch/mips/math-emu/ieee754sp.c
index 15d1e36cfe64..0b6267bc8b0f 100644
--- a/arch/mips/math-emu/ieee754sp.c
+++ b/arch/mips/math-emu/ieee754sp.c
@@ -1,122 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0-only
/* 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.,
- * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
- *
- * ########################################################################
*/
+#include <linux/compiler.h>
#include "ieee754sp.h"
-int ieee754sp_class(ieee754sp x)
+int ieee754sp_class(union ieee754sp x)
{
COMPXSP;
EXPLODEXSP;
return xc;
}
-int ieee754sp_isnan(ieee754sp x)
+static inline int ieee754sp_isnan(union ieee754sp x)
{
- return ieee754sp_class(x) >= IEEE754_CLASS_SNAN;
+ return ieee754_class_nan(ieee754sp_class(x));
}
-int ieee754sp_issnan(ieee754sp x)
+static inline int ieee754sp_issnan(union ieee754sp x)
{
+ int qbit;
+
assert(ieee754sp_isnan(x));
- return (SPMANT(x) & SP_MBIT(SP_MBITS-1));
+ qbit = (SPMANT(x) & SP_MBIT(SP_FBITS - 1)) == SP_MBIT(SP_FBITS - 1);
+ return ieee754_csr.nan2008 ^ qbit;
}
-ieee754sp ieee754sp_xcpt(ieee754sp r, const char *op, ...)
-{
- struct ieee754xctx ax;
-
- if (!TSTX())
- return r;
-
- ax.op = op;
- ax.rt = IEEE754_RT_SP;
- ax.rv.sp = r;
- va_start(ax.ap, op);
- ieee754_xcpt(&ax);
- va_end(ax.ap);
- return ax.rv.sp;
-}
-
-ieee754sp ieee754sp_nanxcpt(ieee754sp r, const char *op, ...)
+/*
+ * 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)
{
- struct ieee754xctx ax;
-
- assert(ieee754sp_isnan(r));
-
- if (!ieee754sp_issnan(r)) /* QNAN does not cause invalid op !! */
- return r;
+ assert(ieee754sp_issnan(r));
- if (!SETANDTESTCX(IEEE754_INVALID_OPERATION)) {
- /* not enabled convert to a quiet NaN */
- SPMANT(r) &= (~SP_MBIT(SP_MBITS-1));
- if (ieee754sp_isnan(r))
- return r;
- else
- return ieee754sp_indef();
+ 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);
}
- ax.op = op;
- ax.rt = 0;
- ax.rv.sp = r;
- va_start(ax.ap, op);
- ieee754_xcpt(&ax);
- va_end(ax.ap);
- return ax.rv.sp;
-}
-
-ieee754sp ieee754sp_bestnan(ieee754sp x, ieee754sp y)
-{
- assert(ieee754sp_isnan(x));
- assert(ieee754sp_isnan(y));
-
- if (SPMANT(x) > SPMANT(y))
- return x;
- else
- return y;
+ return r;
}
-
-static unsigned get_rounding(int sn, unsigned xm)
+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 IEEE754_RZ:
+ case FPU_CSR_RZ:
break;
- case IEEE754_RN:
+ case FPU_CSR_RN:
xm += 0x3 + ((xm >> 3) & 1);
/* xm += (xm&0x8)?0x4:0x3 */
break;
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if (!sn) /* ?? */
xm += 0x8;
break;
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if (sn) /* ?? */
xm += 0x8;
break;
@@ -131,11 +84,11 @@ static unsigned get_rounding(int sn, unsigned xm)
* xe is an unbiased exponent
* xm is 3bit extended precision value.
*/
-ieee754sp ieee754sp_format(int sn, int xe, unsigned xm)
+union ieee754sp ieee754sp_format(int sn, int xe, unsigned int xm)
{
assert(xm); /* we don't gen exact zeros (probably should) */
- assert((xm >> (SP_MBITS + 1 + 3)) == 0); /* no execess */
+ assert((xm >> (SP_FBITS + 1 + 3)) == 0); /* no excess */
assert(xm & (SP_HIDDEN_BIT << 3));
if (xe < SP_EMIN) {
@@ -143,57 +96,57 @@ ieee754sp ieee754sp_format(int sn, int xe, unsigned xm)
int es = SP_EMIN - xe;
if (ieee754_csr.nod) {
- SETCX(IEEE754_UNDERFLOW);
- SETCX(IEEE754_INEXACT);
+ ieee754_setcx(IEEE754_UNDERFLOW);
+ ieee754_setcx(IEEE754_INEXACT);
switch(ieee754_csr.rm) {
- case IEEE754_RN:
- case IEEE754_RZ:
+ case FPU_CSR_RN:
+ case FPU_CSR_RZ:
return ieee754sp_zero(sn);
- case IEEE754_RU: /* toward +Infinity */
- if(sn == 0)
+ case FPU_CSR_RU: /* toward +Infinity */
+ if (sn == 0)
return ieee754sp_min(0);
else
return ieee754sp_zero(1);
- case IEEE754_RD: /* toward -Infinity */
- if(sn == 0)
+ case FPU_CSR_RD: /* toward -Infinity */
+ if (sn == 0)
return ieee754sp_zero(0);
else
return ieee754sp_min(1);
}
}
- if (xe == SP_EMIN - 1
- && get_rounding(sn, xm) >> (SP_MBITS + 1 + 3))
+ if (xe == SP_EMIN - 1 &&
+ ieee754sp_get_rounding(sn, xm) >> (SP_FBITS + 1 + 3))
{
/* Not tiny after rounding */
- SETCX(IEEE754_INEXACT);
- xm = get_rounding(sn, xm);
+ ieee754_setcx(IEEE754_INEXACT);
+ xm = ieee754sp_get_rounding(sn, xm);
xm >>= 1;
/* Clear grs bits */
xm &= ~(SP_MBIT(3) - 1);
xe++;
- }
- else {
+ } else {
/* sticky right shift es bits
*/
- SPXSRSXn(es);
+ xm = XSPSRS(xm, es);
+ xe += es;
assert((xm & (SP_HIDDEN_BIT << 3)) == 0);
assert(xe == SP_EMIN);
}
}
if (xm & (SP_MBIT(3) - 1)) {
- SETCX(IEEE754_INEXACT);
+ ieee754_setcx(IEEE754_INEXACT);
if ((xm & (SP_HIDDEN_BIT << 3)) == 0) {
- SETCX(IEEE754_UNDERFLOW);
+ ieee754_setcx(IEEE754_UNDERFLOW);
}
/* inexact must round of 3 bits
*/
- xm = get_rounding(sn, xm);
+ xm = ieee754sp_get_rounding(sn, xm);
/* adjust exponent for rounding add overflowing
*/
- if (xm >> (SP_MBITS + 1 + 3)) {
+ if (xm >> (SP_FBITS + 1 + 3)) {
/* add causes mantissa overflow */
xm >>= 1;
xe++;
@@ -202,24 +155,24 @@ ieee754sp ieee754sp_format(int sn, int xe, unsigned xm)
/* strip grs bits */
xm >>= 3;
- assert((xm >> (SP_MBITS + 1)) == 0); /* no execess */
+ assert((xm >> (SP_FBITS + 1)) == 0); /* no excess */
assert(xe >= SP_EMIN);
if (xe > SP_EMAX) {
- SETCX(IEEE754_OVERFLOW);
- SETCX(IEEE754_INEXACT);
+ ieee754_setcx(IEEE754_OVERFLOW);
+ ieee754_setcx(IEEE754_INEXACT);
/* -O can be table indexed by (rm,sn) */
switch (ieee754_csr.rm) {
- case IEEE754_RN:
+ case FPU_CSR_RN:
return ieee754sp_inf(sn);
- case IEEE754_RZ:
+ case FPU_CSR_RZ:
return ieee754sp_max(sn);
- case IEEE754_RU: /* toward +Infinity */
+ case FPU_CSR_RU: /* toward +Infinity */
if (sn == 0)
return ieee754sp_inf(0);
else
return ieee754sp_max(1);
- case IEEE754_RD: /* toward -Infinity */
+ case FPU_CSR_RD: /* toward -Infinity */
if (sn == 0)
return ieee754sp_max(0);
else
@@ -232,10 +185,10 @@ ieee754sp ieee754sp_format(int sn, int xe, unsigned xm)
/* we underflow (tiny/zero) */
assert(xe == SP_EMIN);
if (ieee754_csr.mx & IEEE754_UNDERFLOW)
- SETCX(IEEE754_UNDERFLOW);
+ ieee754_setcx(IEEE754_UNDERFLOW);
return buildsp(sn, SP_EMIN - 1 + SP_EBIAS, xm);
} else {
- assert((xm >> (SP_MBITS + 1)) == 0); /* no execess */
+ assert((xm >> (SP_FBITS + 1)) == 0); /* no excess */
assert(xm & SP_HIDDEN_BIT);
return buildsp(sn, xe + SP_EBIAS, xm & ~SP_HIDDEN_BIT);
generated by cgit (git 2.34.1) at 2025-12-25 08:23:14 +0000