PageRenderTime 23ms CodeModel.GetById 18ms app.highlight 2ms RepoModel.GetById 1ms app.codeStats 0ms

/arch/mips/math-emu/dp_fsp.c

http://github.com/mirrors/linux
C | 63 lines | 35 code | 15 blank | 13 comment | 3 complexity | 5f42554989a21d01b2fc5e47fc065e3d MD5 | raw file
 1// SPDX-License-Identifier: GPL-2.0-only
 2/* IEEE754 floating point arithmetic
 3 * double precision: common utilities
 4 */
 5/*
 6 * MIPS floating point support
 7 * Copyright (C) 1994-2000 Algorithmics Ltd.
 8 */
 9
10#include "ieee754sp.h"
11#include "ieee754dp.h"
12
13static inline union ieee754dp ieee754dp_nan_fsp(int xs, u64 xm)
14{
15	return builddp(xs, DP_EMAX + 1 + DP_EBIAS,
16		       xm << (DP_FBITS - SP_FBITS));
17}
18
19union ieee754dp ieee754dp_fsp(union ieee754sp x)
20{
21	COMPXSP;
22
23	EXPLODEXSP;
24
25	ieee754_clearcx();
26
27	FLUSHXSP;
28
29	switch (xc) {
30	case IEEE754_CLASS_SNAN:
31		return ieee754dp_nanxcpt(ieee754dp_nan_fsp(xs, xm));
32
33	case IEEE754_CLASS_QNAN:
34		return ieee754dp_nan_fsp(xs, xm);
35
36	case IEEE754_CLASS_INF:
37		return ieee754dp_inf(xs);
38
39	case IEEE754_CLASS_ZERO:
40		return ieee754dp_zero(xs);
41
42	case IEEE754_CLASS_DNORM:
43		/* normalize */
44		while ((xm >> SP_FBITS) == 0) {
45			xm <<= 1;
46			xe--;
47		}
48		break;
49
50	case IEEE754_CLASS_NORM:
51		break;
52	}
53
54	/*
55	 * Can't possibly overflow,underflow, or need rounding
56	 */
57
58	/* drop the hidden bit */
59	xm &= ~SP_HIDDEN_BIT;
60
61	return builddp(xs, xe + DP_EBIAS,
62		       (u64) xm << (DP_FBITS - SP_FBITS));
63}