math-emu: Fix thinko in _FP_DIV
[linux-2.6.git] / include / math-emu / soft-fp.h
1 /* Software floating-point emulation.
2    Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4    Contributed by Richard Henderson (rth@cygnus.com),
5                   Jakub Jelinek (jj@ultra.linux.cz),
6                   David S. Miller (davem@redhat.com) and
7                   Peter Maydell (pmaydell@chiark.greenend.org.uk).
8
9    The GNU C Library is free software; you can redistribute it and/or
10    modify it under the terms of the GNU Library General Public License as
11    published by the Free Software Foundation; either version 2 of the
12    License, or (at your option) any later version.
13
14    The GNU C Library is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17    Library General Public License for more details.
18
19    You should have received a copy of the GNU Library General Public
20    License along with the GNU C Library; see the file COPYING.LIB.  If
21    not, write to the Free Software Foundation, Inc.,
22    59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
23
24 #ifndef __MATH_EMU_SOFT_FP_H__
25 #define __MATH_EMU_SOFT_FP_H__
26
27 #include <asm/sfp-machine.h>
28
29 /* Allow sfp-machine to have its own byte order definitions. */
30 #ifndef __BYTE_ORDER
31 #include <endian.h>
32 #endif
33
34 #define _FP_WORKBITS            3
35 #define _FP_WORK_LSB            ((_FP_W_TYPE)1 << 3)
36 #define _FP_WORK_ROUND          ((_FP_W_TYPE)1 << 2)
37 #define _FP_WORK_GUARD          ((_FP_W_TYPE)1 << 1)
38 #define _FP_WORK_STICKY         ((_FP_W_TYPE)1 << 0)
39
40 #ifndef FP_RND_NEAREST
41 # define FP_RND_NEAREST         0
42 # define FP_RND_ZERO            1
43 # define FP_RND_PINF            2
44 # define FP_RND_MINF            3
45 #ifndef FP_ROUNDMODE
46 # define FP_ROUNDMODE           FP_RND_NEAREST
47 #endif
48 #endif
49
50 /* By default don't care about exceptions. */
51 #ifndef FP_EX_INVALID
52 #define FP_EX_INVALID           0
53 #endif
54 #ifndef FP_EX_INVALID_SNAN
55 #define FP_EX_INVALID_SNAN      0
56 #endif
57 /* inf - inf */
58 #ifndef FP_EX_INVALID_ISI
59 #define FP_EX_INVALID_ISI       0
60 #endif
61 /* inf / inf */
62 #ifndef FP_EX_INVALID_IDI
63 #define FP_EX_INVALID_IDI       0
64 #endif
65 /* 0 / 0 */
66 #ifndef FP_EX_INVALID_ZDZ
67 #define FP_EX_INVALID_ZDZ       0
68 #endif
69 /* inf * 0 */
70 #ifndef FP_EX_INVALID_IMZ
71 #define FP_EX_INVALID_IMZ       0
72 #endif
73 #ifndef FP_EX_OVERFLOW
74 #define FP_EX_OVERFLOW          0
75 #endif
76 #ifndef FP_EX_UNDERFLOW
77 #define FP_EX_UNDERFLOW         
78 #endif
79 #ifndef FP_EX_DIVZERO
80 #define FP_EX_DIVZERO           0
81 #endif
82 #ifndef FP_EX_INEXACT
83 #define FP_EX_INEXACT           0
84 #endif
85 #ifndef FP_EX_DENORM
86 #define FP_EX_DENORM            0
87 #endif
88
89 #ifdef _FP_DECL_EX
90 #define FP_DECL_EX                                      \
91   int _fex = 0;                                         \
92   _FP_DECL_EX
93 #else
94 #define FP_DECL_EX int _fex = 0
95 #endif
96   
97 #ifndef FP_INIT_ROUNDMODE
98 #define FP_INIT_ROUNDMODE do {} while (0)
99 #endif
100
101 #ifndef FP_HANDLE_EXCEPTIONS
102 #define FP_HANDLE_EXCEPTIONS do {} while (0)
103 #endif
104
105 /* By default we never flush denormal input operands to signed zero. */
106 #ifndef FP_DENORM_ZERO
107 #define FP_DENORM_ZERO 0
108 #endif
109
110 #ifndef FP_INHIBIT_RESULTS
111 /* By default we write the results always.
112  * sfp-machine may override this and e.g.
113  * check if some exceptions are unmasked
114  * and inhibit it in such a case.
115  */
116 #define FP_INHIBIT_RESULTS 0
117 #endif
118
119 #ifndef FP_TRAPPING_EXCEPTIONS
120 #define FP_TRAPPING_EXCEPTIONS 0
121 #endif
122
123 #define FP_SET_EXCEPTION(ex)                            \
124   _fex |= (ex)
125   
126 #define FP_UNSET_EXCEPTION(ex)                          \
127   _fex &= ~(ex)
128
129 #define FP_CUR_EXCEPTIONS                               \
130   (_fex)
131
132 #define FP_CLEAR_EXCEPTIONS                             \
133   _fex = 0
134
135 #define _FP_ROUND_NEAREST(wc, X)                        \
136 do {                                                    \
137     if ((_FP_FRAC_LOW_##wc(X) & 15) != _FP_WORK_ROUND)  \
138       _FP_FRAC_ADDI_##wc(X, _FP_WORK_ROUND);            \
139 } while (0)
140
141 #define _FP_ROUND_ZERO(wc, X)           0
142
143 #define _FP_ROUND_PINF(wc, X)                           \
144 do {                                                    \
145     if (!X##_s && (_FP_FRAC_LOW_##wc(X) & 7))           \
146       _FP_FRAC_ADDI_##wc(X, _FP_WORK_LSB);              \
147 } while (0)
148
149 #define _FP_ROUND_MINF(wc, X)                           \
150 do {                                                    \
151     if (X##_s && (_FP_FRAC_LOW_##wc(X) & 7))            \
152       _FP_FRAC_ADDI_##wc(X, _FP_WORK_LSB);              \
153 } while (0)
154
155 #define _FP_ROUND(wc, X)                        \
156 do {                                            \
157         if (_FP_FRAC_LOW_##wc(X) & 7)           \
158           FP_SET_EXCEPTION(FP_EX_INEXACT);      \
159         switch (FP_ROUNDMODE)                   \
160         {                                       \
161           case FP_RND_NEAREST:                  \
162             _FP_ROUND_NEAREST(wc,X);            \
163             break;                              \
164           case FP_RND_ZERO:                     \
165             _FP_ROUND_ZERO(wc,X);               \
166             break;                              \
167           case FP_RND_PINF:                     \
168             _FP_ROUND_PINF(wc,X);               \
169             break;                              \
170           case FP_RND_MINF:                     \
171             _FP_ROUND_MINF(wc,X);               \
172             break;                              \
173         }                                       \
174 } while (0)
175
176 #define FP_CLS_NORMAL           0
177 #define FP_CLS_ZERO             1
178 #define FP_CLS_INF              2
179 #define FP_CLS_NAN              3
180
181 #define _FP_CLS_COMBINE(x,y)    (((x) << 2) | (y))
182
183 #include <math-emu/op-1.h>
184 #include <math-emu/op-2.h>
185 #include <math-emu/op-4.h>
186 #include <math-emu/op-8.h>
187 #include <math-emu/op-common.h>
188
189 /* Sigh.  Silly things longlong.h needs.  */
190 #define UWtype          _FP_W_TYPE
191 #define W_TYPE_SIZE     _FP_W_TYPE_SIZE
192
193 typedef int SItype __attribute__((mode(SI)));
194 typedef int DItype __attribute__((mode(DI)));
195 typedef unsigned int USItype __attribute__((mode(SI)));
196 typedef unsigned int UDItype __attribute__((mode(DI)));
197 #if _FP_W_TYPE_SIZE == 32
198 typedef unsigned int UHWtype __attribute__((mode(HI)));
199 #elif _FP_W_TYPE_SIZE == 64
200 typedef USItype UHWtype;
201 #endif
202
203 #ifndef umul_ppmm
204 #include <stdlib/longlong.h>
205 #endif
206
207 #endif /* __MATH_EMU_SOFT_FP_H__ */