forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
73 lines
1.4 KiB
73 lines
1.4 KiB
// 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" |
|
#include "ieee754dp.h" |
|
|
|
static inline union ieee754sp ieee754sp_nan_fdp(int xs, u64 xm) |
|
{ |
|
return buildsp(xs, SP_EMAX + 1 + SP_EBIAS, |
|
xm >> (DP_FBITS - SP_FBITS)); |
|
} |
|
|
|
union ieee754sp ieee754sp_fdp(union ieee754dp x) |
|
{ |
|
union ieee754sp y; |
|
u32 rm; |
|
|
|
COMPXDP; |
|
COMPYSP; |
|
|
|
EXPLODEXDP; |
|
|
|
ieee754_clearcx(); |
|
|
|
FLUSHXDP; |
|
|
|
switch (xc) { |
|
case IEEE754_CLASS_SNAN: |
|
x = ieee754dp_nanxcpt(x); |
|
EXPLODEXDP; |
|
fallthrough; |
|
case IEEE754_CLASS_QNAN: |
|
y = ieee754sp_nan_fdp(xs, xm); |
|
if (!ieee754_csr.nan2008) { |
|
EXPLODEYSP; |
|
if (!ieee754_class_nan(yc)) |
|
y = ieee754sp_indef(); |
|
} |
|
return y; |
|
|
|
case IEEE754_CLASS_INF: |
|
return ieee754sp_inf(xs); |
|
|
|
case IEEE754_CLASS_ZERO: |
|
return ieee754sp_zero(xs); |
|
|
|
case IEEE754_CLASS_DNORM: |
|
/* can't possibly be sp representable */ |
|
ieee754_setcx(IEEE754_UNDERFLOW); |
|
ieee754_setcx(IEEE754_INEXACT); |
|
if ((ieee754_csr.rm == FPU_CSR_RU && !xs) || |
|
(ieee754_csr.rm == FPU_CSR_RD && xs)) |
|
return ieee754sp_mind(xs); |
|
return ieee754sp_zero(xs); |
|
|
|
case IEEE754_CLASS_NORM: |
|
break; |
|
} |
|
|
|
/* |
|
* Convert from DP_FBITS to SP_FBITS+3 with sticky right shift. |
|
*/ |
|
rm = (xm >> (DP_FBITS - (SP_FBITS + 3))) | |
|
((xm << (64 - (DP_FBITS - (SP_FBITS + 3)))) != 0); |
|
|
|
return ieee754sp_format(xs, xe, rm); |
|
}
|
|
|