xref: /netbsd-src/external/gpl3/gdb.old/dist/sim/igen/ld-decode.c (revision 8b657b0747480f8989760d71343d6dd33f8d4cf9)
1 /* The IGEN simulator generator for GDB, the GNU Debugger.
2 
3    Copyright 2002-2023 Free Software Foundation, Inc.
4 
5    Contributed by Andrew Cagney.
6 
7    This file is part of GDB.
8 
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 3 of the License, or
12    (at your option) any later version.
13 
14    This program 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
17    GNU General Public License for more details.
18 
19    You should have received a copy of the GNU General Public License
20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
21 
22 
23 /* load the opcode stat structure */
24 
25 #include "misc.h"
26 #include "lf.h"
27 #include "table.h"
28 #include "filter.h"
29 
30 #include "igen.h"
31 
32 #include "ld-decode.h"
33 
34 
35 static const name_map decode_type_map[] = {
36   {"normal", normal_decode_rule},
37   {"boolean", boolean_rule},
38   {NULL, normal_decode_rule},
39 };
40 
41 static const name_map decode_gen_map[] = {
42   {"array", array_gen},
43   {"switch", switch_gen},
44   {"padded-switch", padded_switch_gen},
45   {"goto-switch", goto_switch_gen},
46   {NULL, -1},
47 };
48 
49 static const name_map decode_reserved_map[] = {
50   {"zero-reserved", 1},
51   {NULL, 0},
52 };
53 
54 static const name_map decode_duplicates_map[] = {
55   {"duplicate", 1},
56   {NULL, 0},
57 };
58 
59 static const name_map decode_combine_map[] = {
60   {"combine", 1},
61   {NULL, 0},
62 };
63 
64 static const name_map decode_search_map[] = {
65   {"constants", decode_find_constants},
66   {"mixed", decode_find_mixed},
67   {"strings", decode_find_strings},
68   {NULL, decode_find_mixed},
69 };
70 
71 
72 static void
73 set_bits (int bit[max_insn_bit_size], uint64_t value)
74 {
75   int bit_nr;
76   for (bit_nr = 0; bit_nr < max_insn_bit_size; bit_nr++)
77     {
78       if (bit_nr < options.insn_bit_size)
79 	bit[bit_nr] = (value >> (options.insn_bit_size - bit_nr - 1)) & 1;
80       else
81 	bit[bit_nr] = 0;
82     }
83 }
84 
85 decode_table *
86 load_decode_table (const char *file_name)
87 {
88   table *file = table_open (file_name);
89   table_entry *entry;
90   decode_table *table = NULL;
91   decode_table **curr_rule = &table;
92   while ((entry = table_read (file)) != NULL)
93     {
94       char *decode_options = entry->field[decode_options_field];
95       decode_table *new_rule = ZALLOC (decode_table);
96       if (entry->nr_fields < min_nr_decode_fields)
97 	error (entry->line, "Missing decode table fields\n");
98       new_rule->line = entry->line;
99 
100       /* the options field */
101       new_rule->type = name2i (decode_options, decode_type_map);
102       if (options.decode.overriding_gen != NULL)
103 	new_rule->gen =
104 	  name2i (options.decode.overriding_gen, decode_gen_map);
105       else
106 	new_rule->gen = name2i (decode_options, decode_gen_map);
107       if (new_rule->gen == padded_switch_gen && options.decode.switch_as_goto)
108 	new_rule->gen = goto_switch_gen;
109       if (options.decode.zero_reserved)
110 	new_rule->with_zero_reserved = 1;
111       else
112 	new_rule->with_zero_reserved =
113 	  name2i (decode_options, decode_reserved_map);
114       if (options.decode.duplicate)
115 	new_rule->with_duplicates = 1;
116       else
117 	new_rule->with_duplicates =
118 	  name2i (decode_options, decode_duplicates_map);
119       if (options.decode.combine)
120 	new_rule->with_combine = 1;
121       else
122 	new_rule->with_combine = name2i (decode_options, decode_combine_map);
123       if (new_rule->type == boolean_rule)
124 	{
125 	  char *chp = decode_options;
126 	  while (*chp != '\0')
127 	    {
128 	      if (isdigit (*chp))
129 		{
130 		  new_rule->constant = a2i (chp);
131 		  break;
132 		}
133 	      chp = skip_to_separator (chp, ",");
134 	      if (*chp == ',')
135 		++chp;
136 	      chp = skip_spaces (chp);
137 	    }
138 	}
139 
140       /* First and last */
141       if (entry->nr_fields > decode_first_field
142 	  && strlen (entry->field[decode_first_field]) > 0)
143 	{
144 	  new_rule->first = target_a2i (options.hi_bit_nr,
145 					entry->field[decode_first_field]);
146 	  if (new_rule->first < 0 || new_rule->first >= options.insn_bit_size)
147 	    error (new_rule->line, "First field out of range\n");
148 	}
149       else
150 	new_rule->first = 0;
151       if (entry->nr_fields > decode_last_field
152 	  && strlen (entry->field[decode_last_field]) > 0)
153 	{
154 	  new_rule->last = target_a2i (options.hi_bit_nr,
155 				       entry->field[decode_last_field]);
156 	  if (new_rule->last < 0 || new_rule->last >= options.insn_bit_size)
157 	    error (new_rule->line, "Last field out of range\n");
158 	}
159       else
160 	new_rule->last = options.insn_bit_size - 1;
161       if (new_rule->first > new_rule->last)
162 	error (new_rule->line, "First must preceed last\n");
163 
164       /* force first/last, with default values based on first/last */
165       if (entry->nr_fields > decode_force_first_field
166 	  && strlen (entry->field[decode_force_first_field]) > 0)
167 	{
168 	  new_rule->force_first = target_a2i (options.hi_bit_nr,
169 					      entry->
170 					      field
171 					      [decode_force_first_field]);
172 	  if (new_rule->force_first < new_rule->first
173 	      || new_rule->force_first > new_rule->last + 1)
174 	    error (new_rule->line, "Force first out of range\n");
175 	}
176       else
177 	new_rule->force_first = new_rule->last + 1;
178       if (entry->nr_fields > decode_force_last_field
179 	  && strlen (entry->field[decode_force_last_field]) > 0)
180 	{
181 	  new_rule->force_last = target_a2i (options.hi_bit_nr,
182 					     entry->
183 					     field[decode_force_last_field]);
184 	  if (new_rule->force_last > new_rule->last
185 	      || new_rule->force_last < new_rule->first - 1)
186 	    error (new_rule->line, "Force-last out of range\n");
187 	}
188       else
189 	new_rule->force_last = new_rule->first - 1;
190 
191       /* fields to be treated as constant */
192       if (entry->nr_fields > decode_constant_field_names_field)
193 	filter_parse (&new_rule->constant_field_names,
194 		      entry->field[decode_constant_field_names_field]);
195 
196       /* applicable word nr */
197       if (entry->nr_fields > decode_word_nr_field)
198 	new_rule->word_nr = a2i (entry->field[decode_word_nr_field]);
199 
200       /* required instruction format names */
201       if (entry->nr_fields > decode_format_names_field)
202 	filter_parse (&new_rule->format_names,
203 		      entry->field[decode_format_names_field]);
204 
205       /* required processor models */
206       if (entry->nr_fields > decode_model_names_field)
207 	filter_parse (&new_rule->model_names,
208 		      entry->field[decode_model_names_field]);
209 
210       /* required paths */
211       if (entry->nr_fields > decode_paths_field
212 	  && strlen (entry->field[decode_paths_field]) > 0)
213 	{
214 	  decode_path_list **last = &new_rule->paths;
215 	  char *chp = entry->field[decode_paths_field];
216 	  do
217 	    {
218 	      (*last) = ZALLOC (decode_path_list);
219 	      /* extra root/zero entry */
220 	      (*last)->path = ZALLOC (decode_path);
221 	      do
222 		{
223 		  decode_path *entry = ZALLOC (decode_path);
224 		  entry->opcode_nr = a2i (chp);
225 		  entry->parent = (*last)->path;
226 		  (*last)->path = entry;
227 		  chp = skip_digits (chp);
228 		  chp = skip_spaces (chp);
229 		}
230 	      while (*chp == '.');
231 	      last = &(*last)->next;
232 	    }
233 	  while (*chp == ',');
234 	  if (*chp != '\0')
235 	    error (entry->line, "Invalid path field\n");
236 	}
237 
238       /* collect up the list of optional special conditions applicable
239          to the rule */
240       {
241 	int field_nr = nr_decode_fields;
242 	while (entry->nr_fields > field_nr)
243 	  {
244 	    decode_cond *cond = ZALLOC (decode_cond);
245 	    decode_cond **last;
246 	    if (entry->nr_fields > field_nr + decode_cond_mask_field)
247 	      set_bits (cond->mask,
248 			a2i (entry->
249 			     field[field_nr + decode_cond_mask_field]));
250 	    if (entry->nr_fields > field_nr + decode_cond_value_field)
251 	      {
252 		if (entry->field[field_nr + decode_cond_value_field][0] ==
253 		    '!')
254 		  {
255 		    cond->is_equal = 0;
256 		    set_bits (cond->value,
257 			      a2i (entry->
258 				   field[field_nr + decode_cond_value_field] +
259 				   1));
260 		  }
261 		else
262 		  {
263 		    cond->is_equal = 1;
264 		    set_bits (cond->value,
265 			      a2i (entry->
266 				   field[field_nr +
267 					 decode_cond_value_field]));
268 		  }
269 	      }
270 	    if (entry->nr_fields > field_nr + decode_cond_word_nr_field)
271 	      cond->word_nr =
272 		a2i (entry->field[field_nr + decode_cond_word_nr_field]);
273 	    field_nr += nr_decode_cond_fields;
274 	    /* insert it */
275 	    last = &new_rule->conditions;
276 	    while (*last != NULL)
277 	      last = &(*last)->next;
278 	    *last = cond;
279 	  }
280       }
281       *curr_rule = new_rule;
282       curr_rule = &new_rule->next;
283     }
284   return table;
285 }
286 
287 
288 int
289 decode_table_max_word_nr (const decode_table *entry)
290 {
291   int max_word_nr = 0;
292   while (entry != NULL)
293     {
294       decode_cond *cond;
295       if (entry->word_nr > max_word_nr)
296 	max_word_nr = entry->word_nr;
297       for (cond = entry->conditions; cond != NULL; cond = cond->next)
298 	{
299 	  if (cond->word_nr > max_word_nr)
300 	    max_word_nr = cond->word_nr;
301 	}
302       entry = entry->next;
303     }
304   return max_word_nr;
305 }
306 
307 
308 static void
309 dump_decode_cond (lf *file, const char *prefix, const decode_cond *cond,
310 		  const char *suffix)
311 {
312   lf_printf (file, "%s(decode_cond *) %p", prefix, cond);
313   if (cond != NULL)
314     {
315       lf_indent (file, +1);
316       lf_printf (file, "\n(word_nr %d)", cond->word_nr);
317       lf_printf (file, "\n(mask %p)", cond->mask);
318       lf_printf (file, "\n(value %p)", cond->value);
319       lf_printf (file, "\n(is_equal %d)", cond->is_equal);
320       lf_printf (file, "\n(next (decode_cond *) %p)", cond->next);
321       lf_indent (file, -1);
322     }
323   lf_printf (file, "%s", suffix);
324 }
325 
326 
327 static void
328 dump_decode_conds (lf *file, const char *prefix, const decode_cond *cond,
329 		   const char *suffix)
330 {
331   lf_printf (file, "%s(decode_cond *) %p", prefix, cond);
332   while (cond != NULL)
333     {
334       dump_decode_cond (file, "\n(", cond, ")");
335       cond = cond->next;
336     }
337   lf_printf (file, "%s", suffix);
338 }
339 
340 
341 void
342 dump_decode_rule (lf *file, const char *prefix, const decode_table *rule,
343 		  const char *suffix)
344 {
345   lf_printf (file, "%s(decode_table *) %p", prefix, rule);
346   if (rule != NULL)
347     {
348       lf_indent (file, +1);
349       dump_line_ref (file, "\n(line ", rule->line, ")");
350       lf_printf (file, "\n(type %s)", i2name (rule->type, decode_type_map));
351       lf_printf (file, "\n(gen %s)", i2name (rule->gen, decode_gen_map));
352       lf_printf (file, "\n(first %d)", rule->first);
353       lf_printf (file, "\n(last %d)", rule->last);
354       lf_printf (file, "\n(force_first %d)", rule->force_first);
355       lf_printf (file, "\n(force_last %d)", rule->force_last);
356       dump_filter (file, "\n(constant_field_names \"",
357 		   rule->constant_field_names, "\")");
358       lf_printf (file, "\n(constant 0x%x)", rule->constant);
359       lf_printf (file, "\n(word_nr %d)", rule->word_nr);
360       lf_printf (file, "\n(with_zero_reserved %d)", rule->with_zero_reserved);
361       lf_printf (file, "\n(with_duplicates %d)", rule->with_duplicates);
362       lf_printf (file, "\n(with_combine %d)", rule->with_combine);
363       dump_filter (file, "\n(format_names \"", rule->format_names, "\")");
364       dump_filter (file, "\n(model_names \"", rule->model_names, "\")");
365       dump_decode_conds (file, "\n(conditions ", rule->conditions, ")");
366       lf_printf (file, "\n(next %p)", rule->next);
367       lf_indent (file, -1);
368     }
369   lf_printf (file, "%s", suffix);
370 }
371 
372 
373 #ifdef MAIN
374 
375 static void
376 dump_decode_rules (lf *file,
377 		   const char *prefix,
378 		   const decode_table *rule,
379 		   const char *suffix)
380 {
381   lf_printf (file, "%s", prefix);
382   while (rule != NULL)
383     {
384       lf_indent (file, +1);
385       dump_decode_rule (file, "\n(", rule, ")");
386       lf_indent (file, -1);
387       rule = rule->next;
388     }
389   lf_printf (file, "%s", suffix);
390 }
391 
392 igen_options options;
393 
394 int
395 main (int argc, char **argv)
396 {
397   lf *l;
398   decode_table *rules;
399 
400   INIT_OPTIONS ();
401 
402   if (argc != 3)
403     error (NULL, "Usage: decode <decode-file> <hi-bit-nr>\n");
404 
405   options.hi_bit_nr = a2i (argv[2]);
406   rules = load_decode_table (argv[1]);
407   l = lf_open ("-", "stdout", lf_omit_references, lf_is_text, "tmp-ld-insn");
408   dump_decode_rules (l, "(rules ", rules, ")\n");
409 
410   return 0;
411 }
412 #endif
413