xref: /netbsd-src/external/gpl3/gcc.old/dist/libgcc/soft-fp/op-8.h (revision 867d70fc718005c0918b8b8b2f9d7f2d52d0a0db)
1 /* Software floating-point emulation.
2    Basic eight-word fraction declaration and manipulation.
3    Copyright (C) 1997-2018 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).
8 
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.
13 
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.)
22 
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.
27 
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/>.  */
31 
32 #ifndef SOFT_FP_OP_8_H
33 #define SOFT_FP_OP_8_H	1
34 
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])
42 
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)
73 
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)
104 
105 
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	\
146 	 stable.  */							\
147       X##_f[0] |= (_FP_FRAC_SRS_8_s != 0);				\
148     }									\
149   while (0)
150 
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)
168 
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)
191 
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)
203 
204 #define _FP_MINFRAC_8   0, 0, 0, 0, 0, 0, 0, 1
205 
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)
212 
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)
222 
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)
233 
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)
237 
238 #endif /* !SOFT_FP_OP_8_H */
239