xref: /openbmc/linux/arch/mips/math-emu/ieee754int.h (revision 31b90347)
1 /*
2  * IEEE754 floating point
3  * common internal header file
4  */
5 /*
6  * MIPS floating point support
7  * Copyright (C) 1994-2000 Algorithmics Ltd.
8  *
9  * ########################################################################
10  *
11  *  This program is free software; you can distribute it and/or modify it
12  *  under the terms of the GNU General Public License (Version 2) as
13  *  published by the Free Software Foundation.
14  *
15  *  This program is distributed in the hope it will be useful, but WITHOUT
16  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
17  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
18  *  for more details.
19  *
20  *  You should have received a copy of the GNU General Public License along
21  *  with this program; if not, write to the Free Software Foundation, Inc.,
22  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
23  *
24  * ########################################################################
25  */
26 
27 
28 #include "ieee754.h"
29 
30 #define DP_EBIAS	1023
31 #define DP_EMIN		(-1022)
32 #define DP_EMAX		1023
33 #define DP_MBITS	52
34 
35 #define SP_EBIAS	127
36 #define SP_EMIN		(-126)
37 #define SP_EMAX		127
38 #define SP_MBITS	23
39 
40 #define DP_MBIT(x)	((u64)1 << (x))
41 #define DP_HIDDEN_BIT	DP_MBIT(DP_MBITS)
42 #define DP_SIGN_BIT	DP_MBIT(63)
43 
44 #define SP_MBIT(x)	((u32)1 << (x))
45 #define SP_HIDDEN_BIT	SP_MBIT(SP_MBITS)
46 #define SP_SIGN_BIT	SP_MBIT(31)
47 
48 
49 #define SPSIGN(sp)	(sp.parts.sign)
50 #define SPBEXP(sp)	(sp.parts.bexp)
51 #define SPMANT(sp)	(sp.parts.mant)
52 
53 #define DPSIGN(dp)	(dp.parts.sign)
54 #define DPBEXP(dp)	(dp.parts.bexp)
55 #define DPMANT(dp)	(dp.parts.mant)
56 
57 #define CLPAIR(x, y)	((x)*6+(y))
58 
59 #define CLEARCX \
60   (ieee754_csr.cx = 0)
61 
62 #define SETCX(x) \
63   (ieee754_csr.cx |= (x), ieee754_csr.sx |= (x))
64 
65 #define SETANDTESTCX(x) \
66   (SETCX(x), ieee754_csr.mx & (x))
67 
68 #define TSTX()	\
69 	(ieee754_csr.cx & ieee754_csr.mx)
70 
71 
72 #define COMPXSP \
73   unsigned xm; int xe; int xs __maybe_unused; int xc
74 
75 #define COMPYSP \
76   unsigned ym; int ye; int ys; int yc
77 
78 #define EXPLODESP(v, vc, vs, ve, vm) \
79 {\
80     vs = SPSIGN(v);\
81     ve = SPBEXP(v);\
82     vm = SPMANT(v);\
83     if(ve == SP_EMAX+1+SP_EBIAS){\
84 	if(vm == 0)\
85 	  vc = IEEE754_CLASS_INF;\
86 	else if(vm & SP_MBIT(SP_MBITS-1)) \
87 	  vc = IEEE754_CLASS_SNAN;\
88 	else \
89 	  vc = IEEE754_CLASS_QNAN;\
90     } else if(ve == SP_EMIN-1+SP_EBIAS) {\
91 	if(vm) {\
92 	    ve = SP_EMIN;\
93 	    vc = IEEE754_CLASS_DNORM;\
94 	} else\
95 	  vc = IEEE754_CLASS_ZERO;\
96     } else {\
97 	ve -= SP_EBIAS;\
98 	vm |= SP_HIDDEN_BIT;\
99 	vc = IEEE754_CLASS_NORM;\
100     }\
101 }
102 #define EXPLODEXSP EXPLODESP(x, xc, xs, xe, xm)
103 #define EXPLODEYSP EXPLODESP(y, yc, ys, ye, ym)
104 
105 
106 #define COMPXDP \
107 u64 xm; int xe; int xs __maybe_unused; int xc
108 
109 #define COMPYDP \
110 u64 ym; int ye; int ys; int yc
111 
112 #define EXPLODEDP(v, vc, vs, ve, vm) \
113 {\
114     vm = DPMANT(v);\
115     vs = DPSIGN(v);\
116     ve = DPBEXP(v);\
117     if(ve == DP_EMAX+1+DP_EBIAS){\
118 	if(vm == 0)\
119 	  vc = IEEE754_CLASS_INF;\
120 	else if(vm & DP_MBIT(DP_MBITS-1)) \
121 	  vc = IEEE754_CLASS_SNAN;\
122 	else \
123 	  vc = IEEE754_CLASS_QNAN;\
124     } else if(ve == DP_EMIN-1+DP_EBIAS) {\
125 	if(vm) {\
126 	    ve = DP_EMIN;\
127 	    vc = IEEE754_CLASS_DNORM;\
128 	} else\
129 	  vc = IEEE754_CLASS_ZERO;\
130     } else {\
131 	ve -= DP_EBIAS;\
132 	vm |= DP_HIDDEN_BIT;\
133 	vc = IEEE754_CLASS_NORM;\
134     }\
135 }
136 #define EXPLODEXDP EXPLODEDP(x, xc, xs, xe, xm)
137 #define EXPLODEYDP EXPLODEDP(y, yc, ys, ye, ym)
138 
139 #define FLUSHDP(v, vc, vs, ve, vm) \
140 	if(vc==IEEE754_CLASS_DNORM) {\
141 	    if(ieee754_csr.nod) {\
142 		SETCX(IEEE754_INEXACT);\
143 		vc = IEEE754_CLASS_ZERO;\
144 		ve = DP_EMIN-1+DP_EBIAS;\
145 		vm = 0;\
146 		v = ieee754dp_zero(vs);\
147 	    }\
148 	}
149 
150 #define FLUSHSP(v, vc, vs, ve, vm) \
151 	if(vc==IEEE754_CLASS_DNORM) {\
152 	    if(ieee754_csr.nod) {\
153 		SETCX(IEEE754_INEXACT);\
154 		vc = IEEE754_CLASS_ZERO;\
155 		ve = SP_EMIN-1+SP_EBIAS;\
156 		vm = 0;\
157 		v = ieee754sp_zero(vs);\
158 	    }\
159 	}
160 
161 #define FLUSHXDP FLUSHDP(x, xc, xs, xe, xm)
162 #define FLUSHYDP FLUSHDP(y, yc, ys, ye, ym)
163 #define FLUSHXSP FLUSHSP(x, xc, xs, xe, xm)
164 #define FLUSHYSP FLUSHSP(y, yc, ys, ye, ym)
165