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ieee754int.h
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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)