forked from Minki/linux
9d5a634946
Based on 1 normalized pattern(s): 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 33 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531081038.563233189@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
97 lines
1.9 KiB
C
97 lines
1.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/* IEEE754 floating point arithmetic
|
|
* single precision
|
|
*/
|
|
/*
|
|
* MIPS floating point support
|
|
* Copyright (C) 1994-2000 Algorithmics Ltd.
|
|
*/
|
|
|
|
#include "ieee754sp.h"
|
|
|
|
s64 ieee754sp_tlong(union ieee754sp x)
|
|
{
|
|
u32 residue;
|
|
int round;
|
|
int sticky;
|
|
int odd;
|
|
|
|
COMPXDP; /* <-- need 64-bit mantissa tmp */
|
|
|
|
ieee754_clearcx();
|
|
|
|
EXPLODEXSP;
|
|
FLUSHXSP;
|
|
|
|
switch (xc) {
|
|
case IEEE754_CLASS_SNAN:
|
|
case IEEE754_CLASS_QNAN:
|
|
ieee754_setcx(IEEE754_INVALID_OPERATION);
|
|
return ieee754di_indef();
|
|
|
|
case IEEE754_CLASS_INF:
|
|
ieee754_setcx(IEEE754_INVALID_OPERATION);
|
|
return ieee754di_overflow(xs);
|
|
|
|
case IEEE754_CLASS_ZERO:
|
|
return 0;
|
|
|
|
case IEEE754_CLASS_DNORM:
|
|
case IEEE754_CLASS_NORM:
|
|
break;
|
|
}
|
|
if (xe >= 63) {
|
|
/* look for valid corner case */
|
|
if (xe == 63 && xs && xm == SP_HIDDEN_BIT)
|
|
return -0x8000000000000000LL;
|
|
/* Set invalid. We will only use overflow for floating
|
|
point overflow */
|
|
ieee754_setcx(IEEE754_INVALID_OPERATION);
|
|
return ieee754di_overflow(xs);
|
|
}
|
|
/* oh gawd */
|
|
if (xe > SP_FBITS) {
|
|
xm <<= xe - SP_FBITS;
|
|
} else if (xe < SP_FBITS) {
|
|
if (xe < -1) {
|
|
residue = xm;
|
|
round = 0;
|
|
sticky = residue != 0;
|
|
xm = 0;
|
|
} else {
|
|
residue = xm << (32 - SP_FBITS + xe);
|
|
round = (residue >> 31) != 0;
|
|
sticky = (residue << 1) != 0;
|
|
xm >>= SP_FBITS - xe;
|
|
}
|
|
odd = (xm & 0x1) != 0x0;
|
|
switch (ieee754_csr.rm) {
|
|
case FPU_CSR_RN:
|
|
if (round && (sticky || odd))
|
|
xm++;
|
|
break;
|
|
case FPU_CSR_RZ:
|
|
break;
|
|
case FPU_CSR_RU: /* toward +Infinity */
|
|
if ((round || sticky) && !xs)
|
|
xm++;
|
|
break;
|
|
case FPU_CSR_RD: /* toward -Infinity */
|
|
if ((round || sticky) && xs)
|
|
xm++;
|
|
break;
|
|
}
|
|
if ((xm >> 63) != 0) {
|
|
/* This can happen after rounding */
|
|
ieee754_setcx(IEEE754_INVALID_OPERATION);
|
|
return ieee754di_overflow(xs);
|
|
}
|
|
if (round || sticky)
|
|
ieee754_setcx(IEEE754_INEXACT);
|
|
}
|
|
if (xs)
|
|
return -xm;
|
|
else
|
|
return xm;
|
|
}
|