| blob | 2014a8e924e703bda497f5fa8e6b3b18f8ecf5ea |
1 /* Software floating-point emulation.
2 Basic eight-word fraction declaration and manipulation.
3 Copyright (C) 1997-2019 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
5 Contributed by Richard Henderson (rth@cygnus.com),
6 Jakub Jelinek (jj@ultra.linux.cz) and
7 Peter Maydell (pmaydell@chiark.greenend.org.uk).
9 The GNU C Library is free software; you can redistribute it and/or
10 modify it under the terms of the GNU Lesser General Public
11 License as published by the Free Software Foundation; either
12 version 2.1 of the License, or (at your option) any later version.
14 In addition to the permissions in the GNU Lesser General Public
15 License, the Free Software Foundation gives you unlimited
16 permission to link the compiled version of this file into
17 combinations with other programs, and to distribute those
18 combinations without any restriction coming from the use of this
19 file. (The Lesser General Public License restrictions do apply in
20 other respects; for example, they cover modification of the file,
21 and distribution when not linked into a combine executable.)
23 The GNU C Library is distributed in the hope that it will be useful,
24 but WITHOUT ANY WARRANTY; without even the implied warranty of
25 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
26 Lesser General Public License for more details.
28 You should have received a copy of the GNU Lesser General Public
29 License along with the GNU C Library; if not, see
30 <http://www.gnu.org/licenses/>. */
32 #ifndef SOFT_FP_OP_8_H
33 #define SOFT_FP_OP_8_H 1
35 /* We need just a few things from here for op-4, if we ever need some
36 other macros, they can be added. */
37 #define _FP_FRAC_DECL_8(X) _FP_W_TYPE X##_f[8]
38 #define _FP_FRAC_SET_8(X, I) __FP_FRAC_SET_8 (X, I)
39 #define _FP_FRAC_HIGH_8(X) (X##_f[7])
40 #define _FP_FRAC_LOW_8(X) (X##_f[0])
41 #define _FP_FRAC_WORD_8(X, w) (X##_f[w])
43 #define _FP_FRAC_SLL_8(X, N) \
44 do \
45 { \
46 _FP_I_TYPE _FP_FRAC_SLL_8_up, _FP_FRAC_SLL_8_down; \
47 _FP_I_TYPE _FP_FRAC_SLL_8_skip, _FP_FRAC_SLL_8_i; \
48 _FP_FRAC_SLL_8_skip = (N) / _FP_W_TYPE_SIZE; \
49 _FP_FRAC_SLL_8_up = (N) % _FP_W_TYPE_SIZE; \
50 _FP_FRAC_SLL_8_down = _FP_W_TYPE_SIZE - _FP_FRAC_SLL_8_up; \
51 if (!_FP_FRAC_SLL_8_up) \
52 for (_FP_FRAC_SLL_8_i = 7; \
53 _FP_FRAC_SLL_8_i >= _FP_FRAC_SLL_8_skip; \
54 --_FP_FRAC_SLL_8_i) \
55 X##_f[_FP_FRAC_SLL_8_i] \
56 = X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip]; \
57 else \
58 { \
59 for (_FP_FRAC_SLL_8_i = 7; \
60 _FP_FRAC_SLL_8_i > _FP_FRAC_SLL_8_skip; \
61 --_FP_FRAC_SLL_8_i) \
62 X##_f[_FP_FRAC_SLL_8_i] \
63 = ((X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip] \
64 << _FP_FRAC_SLL_8_up) \
65 | (X##_f[_FP_FRAC_SLL_8_i-_FP_FRAC_SLL_8_skip-1] \
66 >> _FP_FRAC_SLL_8_down)); \
67 X##_f[_FP_FRAC_SLL_8_i--] = X##_f[0] << _FP_FRAC_SLL_8_up; \
68 } \
69 for (; _FP_FRAC_SLL_8_i >= 0; --_FP_FRAC_SLL_8_i) \
70 X##_f[_FP_FRAC_SLL_8_i] = 0; \
71 } \
72 while (0)
74 #define _FP_FRAC_SRL_8(X, N) \
75 do \
76 { \
77 _FP_I_TYPE _FP_FRAC_SRL_8_up, _FP_FRAC_SRL_8_down; \
78 _FP_I_TYPE _FP_FRAC_SRL_8_skip, _FP_FRAC_SRL_8_i; \
79 _FP_FRAC_SRL_8_skip = (N) / _FP_W_TYPE_SIZE; \
80 _FP_FRAC_SRL_8_down = (N) % _FP_W_TYPE_SIZE; \
81 _FP_FRAC_SRL_8_up = _FP_W_TYPE_SIZE - _FP_FRAC_SRL_8_down; \
82 if (!_FP_FRAC_SRL_8_down) \
83 for (_FP_FRAC_SRL_8_i = 0; \
84 _FP_FRAC_SRL_8_i <= 7-_FP_FRAC_SRL_8_skip; \
85 ++_FP_FRAC_SRL_8_i) \
86 X##_f[_FP_FRAC_SRL_8_i] \
87 = X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip]; \
88 else \
89 { \
90 for (_FP_FRAC_SRL_8_i = 0; \
91 _FP_FRAC_SRL_8_i < 7-_FP_FRAC_SRL_8_skip; \
92 ++_FP_FRAC_SRL_8_i) \
93 X##_f[_FP_FRAC_SRL_8_i] \
94 = ((X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip] \
95 >> _FP_FRAC_SRL_8_down) \
96 | (X##_f[_FP_FRAC_SRL_8_i+_FP_FRAC_SRL_8_skip+1] \
97 << _FP_FRAC_SRL_8_up)); \
98 X##_f[_FP_FRAC_SRL_8_i++] = X##_f[7] >> _FP_FRAC_SRL_8_down; \
99 } \
100 for (; _FP_FRAC_SRL_8_i < 8; ++_FP_FRAC_SRL_8_i) \
101 X##_f[_FP_FRAC_SRL_8_i] = 0; \
102 } \
103 while (0)
106 /* Right shift with sticky-lsb.
107 What this actually means is that we do a standard right-shift,
108 but that if any of the bits that fall off the right hand side
109 were one then we always set the LSbit. */
110 #define _FP_FRAC_SRS_8(X, N, size) \
111 do \
112 { \
113 _FP_I_TYPE _FP_FRAC_SRS_8_up, _FP_FRAC_SRS_8_down; \
114 _FP_I_TYPE _FP_FRAC_SRS_8_skip, _FP_FRAC_SRS_8_i; \
115 _FP_W_TYPE _FP_FRAC_SRS_8_s; \
116 _FP_FRAC_SRS_8_skip = (N) / _FP_W_TYPE_SIZE; \
117 _FP_FRAC_SRS_8_down = (N) % _FP_W_TYPE_SIZE; \
118 _FP_FRAC_SRS_8_up = _FP_W_TYPE_SIZE - _FP_FRAC_SRS_8_down; \
119 for (_FP_FRAC_SRS_8_s = _FP_FRAC_SRS_8_i = 0; \
120 _FP_FRAC_SRS_8_i < _FP_FRAC_SRS_8_skip; \
121 ++_FP_FRAC_SRS_8_i) \
122 _FP_FRAC_SRS_8_s |= X##_f[_FP_FRAC_SRS_8_i]; \
123 if (!_FP_FRAC_SRS_8_down) \
124 for (_FP_FRAC_SRS_8_i = 0; \
125 _FP_FRAC_SRS_8_i <= 7-_FP_FRAC_SRS_8_skip; \
126 ++_FP_FRAC_SRS_8_i) \
127 X##_f[_FP_FRAC_SRS_8_i] \
128 = X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip]; \
129 else \
130 { \
131 _FP_FRAC_SRS_8_s \
132 |= X##_f[_FP_FRAC_SRS_8_i] << _FP_FRAC_SRS_8_up; \
133 for (_FP_FRAC_SRS_8_i = 0; \
134 _FP_FRAC_SRS_8_i < 7-_FP_FRAC_SRS_8_skip; \
135 ++_FP_FRAC_SRS_8_i) \
136 X##_f[_FP_FRAC_SRS_8_i] \
137 = ((X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip] \
138 >> _FP_FRAC_SRS_8_down) \
139 | (X##_f[_FP_FRAC_SRS_8_i+_FP_FRAC_SRS_8_skip+1] \
140 << _FP_FRAC_SRS_8_up)); \
141 X##_f[_FP_FRAC_SRS_8_i++] = X##_f[7] >> _FP_FRAC_SRS_8_down; \
142 } \
143 for (; _FP_FRAC_SRS_8_i < 8; ++_FP_FRAC_SRS_8_i) \
144 X##_f[_FP_FRAC_SRS_8_i] = 0; \
145 /* Don't fix the LSB until the very end when we're sure f[0] is \
147 X##_f[0] |= (_FP_FRAC_SRS_8_s != 0); \
148 } \
149 while (0)
151 #define _FP_FRAC_ADD_8(R, X, Y) \
152 do \
153 { \
154 _FP_W_TYPE _FP_FRAC_ADD_8_c = 0; \
155 _FP_I_TYPE _FP_FRAC_ADD_8_i; \
156 for (_FP_FRAC_ADD_8_i = 0; _FP_FRAC_ADD_8_i < 8; ++_FP_FRAC_ADD_8_i) \
157 { \
158 R##_f[_FP_FRAC_ADD_8_i] \
159 = (X##_f[_FP_FRAC_ADD_8_i] + Y##_f[_FP_FRAC_ADD_8_i] \
160 + _FP_FRAC_ADD_8_c); \
161 _FP_FRAC_ADD_8_c \
162 = (_FP_FRAC_ADD_8_c \
163 ? R##_f[_FP_FRAC_ADD_8_i] <= X##_f[_FP_FRAC_ADD_8_i] \
164 : R##_f[_FP_FRAC_ADD_8_i] < X##_f[_FP_FRAC_ADD_8_i]); \
165 } \
166 } \
167 while (0)
169 #define _FP_FRAC_SUB_8(R, X, Y) \
170 do \
171 { \
172 _FP_W_TYPE _FP_FRAC_SUB_8_tmp[8]; \
173 _FP_W_TYPE _FP_FRAC_SUB_8_c = 0; \
174 _FP_I_TYPE _FP_FRAC_SUB_8_i; \
175 for (_FP_FRAC_SUB_8_i = 0; _FP_FRAC_SUB_8_i < 8; ++_FP_FRAC_SUB_8_i) \
176 { \
177 _FP_FRAC_SUB_8_tmp[_FP_FRAC_SUB_8_i] \
178 = (X##_f[_FP_FRAC_SUB_8_i] - Y##_f[_FP_FRAC_SUB_8_i] \
179 - _FP_FRAC_SUB_8_c); \
180 _FP_FRAC_SUB_8_c \
181 = (_FP_FRAC_SUB_8_c \
182 ? (_FP_FRAC_SUB_8_tmp[_FP_FRAC_SUB_8_i] \
183 >= X##_f[_FP_FRAC_SUB_8_i]) \
184 : (_FP_FRAC_SUB_8_tmp[_FP_FRAC_SUB_8_i] \
185 > X##_f[_FP_FRAC_SUB_8_i])); \
186 } \
187 for (_FP_FRAC_SUB_8_i = 0; _FP_FRAC_SUB_8_i < 8; ++_FP_FRAC_SUB_8_i) \
188 R##_f[_FP_FRAC_SUB_8_i] = _FP_FRAC_SUB_8_tmp[_FP_FRAC_SUB_8_i]; \
189 } \
190 while (0)
192 #define _FP_FRAC_CLZ_8(R, X) \
193 do \
194 { \
195 _FP_I_TYPE _FP_FRAC_CLZ_8_i; \
196 for (_FP_FRAC_CLZ_8_i = 7; _FP_FRAC_CLZ_8_i > 0; _FP_FRAC_CLZ_8_i--) \
197 if (X##_f[_FP_FRAC_CLZ_8_i]) \
198 break; \
199 __FP_CLZ ((R), X##_f[_FP_FRAC_CLZ_8_i]); \
200 (R) += _FP_W_TYPE_SIZE * (7 - _FP_FRAC_CLZ_8_i); \
201 } \
202 while (0)
204 #define _FP_MINFRAC_8 0, 0, 0, 0, 0, 0, 0, 1
206 #define _FP_FRAC_NEGP_8(X) ((_FP_WS_TYPE) X##_f[7] < 0)
207 #define _FP_FRAC_ZEROP_8(X) \
208 ((X##_f[0] | X##_f[1] | X##_f[2] | X##_f[3] \
209 | X##_f[4] | X##_f[5] | X##_f[6] | X##_f[7]) == 0)
210 #define _FP_FRAC_HIGHBIT_DW_8(fs, X) \
211 (_FP_FRAC_HIGH_DW_##fs (X) & _FP_HIGHBIT_DW_##fs)
213 #define _FP_FRAC_COPY_4_8(D, S) \
214 do \
215 { \
216 D##_f[0] = S##_f[0]; \
217 D##_f[1] = S##_f[1]; \
218 D##_f[2] = S##_f[2]; \
219 D##_f[3] = S##_f[3]; \
220 } \
221 while (0)
223 #define _FP_FRAC_COPY_8_4(D, S) \
224 do \
225 { \
226 D##_f[0] = S##_f[0]; \
227 D##_f[1] = S##_f[1]; \
228 D##_f[2] = S##_f[2]; \
229 D##_f[3] = S##_f[3]; \
230 D##_f[4] = D##_f[5] = D##_f[6] = D##_f[7]= 0; \
231 } \
232 while (0)
234 #define __FP_FRAC_SET_8(X, I7, I6, I5, I4, I3, I2, I1, I0) \
235 (X##_f[7] = I7, X##_f[6] = I6, X##_f[5] = I5, X##_f[4] = I4, \
236 X##_f[3] = I3, X##_f[2] = I2, X##_f[1] = I1, X##_f[0] = I0)