xref: /netbsd-src/external/gpl3/gdb/dist/sim/igen/ld-decode.c (revision 71f621822dbfd5073a314948bec169b7bb05f7be)
1 /* The IGEN simulator generator for GDB, the GNU Debugger.
2 
3    Copyright 2002-2024 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 #if 0
65 static const name_map decode_search_map[] = {
66   {"constants", decode_find_constants},
67   {"mixed", decode_find_mixed},
68   {"strings", decode_find_strings},
69   {NULL, decode_find_mixed},
70 };
71 #endif
72 
73 
74 static void
75 set_bits (int bit[max_insn_bit_size], uint64_t value)
76 {
77   int bit_nr;
78   for (bit_nr = 0; bit_nr < max_insn_bit_size; bit_nr++)
79     {
80       if (bit_nr < options.insn_bit_size)
81 	bit[bit_nr] = (value >> (options.insn_bit_size - bit_nr - 1)) & 1;
82       else
83 	bit[bit_nr] = 0;
84     }
85 }
86 
87 decode_table *
88 load_decode_table (const char *file_name)
89 {
90   table *file = table_open (file_name);
91   table_entry *entry;
92   decode_table *table = NULL;
93   decode_table **curr_rule = &table;
94   while ((entry = table_read (file)) != NULL)
95     {
96       char *decode_options = entry->field[decode_options_field];
97       decode_table *new_rule = ZALLOC (decode_table);
98       if (entry->nr_fields < min_nr_decode_fields)
99 	error (entry->line, "Missing decode table fields\n");
100       new_rule->line = entry->line;
101 
102       /* the options field */
103       new_rule->type = name2i (decode_options, decode_type_map);
104       if (options.decode.overriding_gen != NULL)
105 	new_rule->gen =
106 	  name2i (options.decode.overriding_gen, decode_gen_map);
107       else
108 	new_rule->gen = name2i (decode_options, decode_gen_map);
109       if (new_rule->gen == padded_switch_gen && options.decode.switch_as_goto)
110 	new_rule->gen = goto_switch_gen;
111       if (options.decode.zero_reserved)
112 	new_rule->with_zero_reserved = 1;
113       else
114 	new_rule->with_zero_reserved =
115 	  name2i (decode_options, decode_reserved_map);
116       if (options.decode.duplicate)
117 	new_rule->with_duplicates = 1;
118       else
119 	new_rule->with_duplicates =
120 	  name2i (decode_options, decode_duplicates_map);
121       if (options.decode.combine)
122 	new_rule->with_combine = 1;
123       else
124 	new_rule->with_combine = name2i (decode_options, decode_combine_map);
125       if (new_rule->type == boolean_rule)
126 	{
127 	  char *chp = decode_options;
128 	  while (*chp != '\0')
129 	    {
130 	      if (isdigit (*chp))
131 		{
132 		  new_rule->constant = a2i (chp);
133 		  break;
134 		}
135 	      chp = skip_to_separator (chp, ",");
136 	      if (*chp == ',')
137 		++chp;
138 	      chp = skip_spaces (chp);
139 	    }
140 	}
141 
142       /* First and last */
143       if (entry->nr_fields > decode_first_field
144 	  && strlen (entry->field[decode_first_field]) > 0)
145 	{
146 	  new_rule->first = target_a2i (options.hi_bit_nr,
147 					entry->field[decode_first_field]);
148 	  if (new_rule->first < 0 || new_rule->first >= options.insn_bit_size)
149 	    error (new_rule->line, "First field out of range\n");
150 	}
151       else
152 	new_rule->first = 0;
153       if (entry->nr_fields > decode_last_field
154 	  && strlen (entry->field[decode_last_field]) > 0)
155 	{
156 	  new_rule->last = target_a2i (options.hi_bit_nr,
157 				       entry->field[decode_last_field]);
158 	  if (new_rule->last < 0 || new_rule->last >= options.insn_bit_size)
159 	    error (new_rule->line, "Last field out of range\n");
160 	}
161       else
162 	new_rule->last = options.insn_bit_size - 1;
163       if (new_rule->first > new_rule->last)
164 	error (new_rule->line, "First must preceed last\n");
165 
166       /* force first/last, with default values based on first/last */
167       if (entry->nr_fields > decode_force_first_field
168 	  && strlen (entry->field[decode_force_first_field]) > 0)
169 	{
170 	  new_rule->force_first = target_a2i (options.hi_bit_nr,
171 					      entry->
172 					      field
173 					      [decode_force_first_field]);
174 	  if (new_rule->force_first < new_rule->first
175 	      || new_rule->force_first > new_rule->last + 1)
176 	    error (new_rule->line, "Force first out of range\n");
177 	}
178       else
179 	new_rule->force_first = new_rule->last + 1;
180       if (entry->nr_fields > decode_force_last_field
181 	  && strlen (entry->field[decode_force_last_field]) > 0)
182 	{
183 	  new_rule->force_last = target_a2i (options.hi_bit_nr,
184 					     entry->
185 					     field[decode_force_last_field]);
186 	  if (new_rule->force_last > new_rule->last
187 	      || new_rule->force_last < new_rule->first - 1)
188 	    error (new_rule->line, "Force-last out of range\n");
189 	}
190       else
191 	new_rule->force_last = new_rule->first - 1;
192 
193       /* fields to be treated as constant */
194       if (entry->nr_fields > decode_constant_field_names_field)
195 	filter_parse (&new_rule->constant_field_names,
196 		      entry->field[decode_constant_field_names_field]);
197 
198       /* applicable word nr */
199       if (entry->nr_fields > decode_word_nr_field)
200 	new_rule->word_nr = a2i (entry->field[decode_word_nr_field]);
201 
202       /* required instruction format names */
203       if (entry->nr_fields > decode_format_names_field)
204 	filter_parse (&new_rule->format_names,
205 		      entry->field[decode_format_names_field]);
206 
207       /* required processor models */
208       if (entry->nr_fields > decode_model_names_field)
209 	filter_parse (&new_rule->model_names,
210 		      entry->field[decode_model_names_field]);
211 
212       /* required paths */
213       if (entry->nr_fields > decode_paths_field
214 	  && strlen (entry->field[decode_paths_field]) > 0)
215 	{
216 	  decode_path_list **last = &new_rule->paths;
217 	  char *chp = entry->field[decode_paths_field];
218 	  do
219 	    {
220 	      (*last) = ZALLOC (decode_path_list);
221 	      /* extra root/zero entry */
222 	      (*last)->path = ZALLOC (decode_path);
223 	      do
224 		{
225 		  decode_path *entry = ZALLOC (decode_path);
226 		  entry->opcode_nr = a2i (chp);
227 		  entry->parent = (*last)->path;
228 		  (*last)->path = entry;
229 		  chp = skip_digits (chp);
230 		  chp = skip_spaces (chp);
231 		}
232 	      while (*chp == '.');
233 	      last = &(*last)->next;
234 	    }
235 	  while (*chp == ',');
236 	  if (*chp != '\0')
237 	    error (entry->line, "Invalid path field\n");
238 	}
239 
240       /* collect up the list of optional special conditions applicable
241          to the rule */
242       {
243 	int field_nr = nr_decode_fields;
244 	while (entry->nr_fields > field_nr)
245 	  {
246 	    decode_cond *cond = ZALLOC (decode_cond);
247 	    decode_cond **last;
248 	    if (entry->nr_fields > field_nr + decode_cond_mask_field)
249 	      set_bits (cond->mask,
250 			a2i (entry->
251 			     field[field_nr + decode_cond_mask_field]));
252 	    if (entry->nr_fields > field_nr + decode_cond_value_field)
253 	      {
254 		if (entry->field[field_nr + decode_cond_value_field][0] ==
255 		    '!')
256 		  {
257 		    cond->is_equal = 0;
258 		    set_bits (cond->value,
259 			      a2i (entry->
260 				   field[field_nr + decode_cond_value_field] +
261 				   1));
262 		  }
263 		else
264 		  {
265 		    cond->is_equal = 1;
266 		    set_bits (cond->value,
267 			      a2i (entry->
268 				   field[field_nr +
269 					 decode_cond_value_field]));
270 		  }
271 	      }
272 	    if (entry->nr_fields > field_nr + decode_cond_word_nr_field)
273 	      cond->word_nr =
274 		a2i (entry->field[field_nr + decode_cond_word_nr_field]);
275 	    field_nr += nr_decode_cond_fields;
276 	    /* insert it */
277 	    last = &new_rule->conditions;
278 	    while (*last != NULL)
279 	      last = &(*last)->next;
280 	    *last = cond;
281 	  }
282       }
283       *curr_rule = new_rule;
284       curr_rule = &new_rule->next;
285     }
286   return table;
287 }
288 
289 
290 int
291 decode_table_max_word_nr (const decode_table *entry)
292 {
293   int max_word_nr = 0;
294   while (entry != NULL)
295     {
296       decode_cond *cond;
297       if (entry->word_nr > max_word_nr)
298 	max_word_nr = entry->word_nr;
299       for (cond = entry->conditions; cond != NULL; cond = cond->next)
300 	{
301 	  if (cond->word_nr > max_word_nr)
302 	    max_word_nr = cond->word_nr;
303 	}
304       entry = entry->next;
305     }
306   return max_word_nr;
307 }
308 
309 
310 static void
311 dump_decode_cond (lf *file, const char *prefix, const decode_cond *cond,
312 		  const char *suffix)
313 {
314   lf_printf (file, "%s(decode_cond *) %p", prefix, cond);
315   if (cond != NULL)
316     {
317       lf_indent (file, +1);
318       lf_printf (file, "\n(word_nr %d)", cond->word_nr);
319       lf_printf (file, "\n(mask %p)", cond->mask);
320       lf_printf (file, "\n(value %p)", cond->value);
321       lf_printf (file, "\n(is_equal %d)", cond->is_equal);
322       lf_printf (file, "\n(next (decode_cond *) %p)", cond->next);
323       lf_indent (file, -1);
324     }
325   lf_printf (file, "%s", suffix);
326 }
327 
328 
329 static void
330 dump_decode_conds (lf *file, const char *prefix, const decode_cond *cond,
331 		   const char *suffix)
332 {
333   lf_printf (file, "%s(decode_cond *) %p", prefix, cond);
334   while (cond != NULL)
335     {
336       dump_decode_cond (file, "\n(", cond, ")");
337       cond = cond->next;
338     }
339   lf_printf (file, "%s", suffix);
340 }
341 
342 
343 void
344 dump_decode_rule (lf *file, const char *prefix, const decode_table *rule,
345 		  const char *suffix)
346 {
347   lf_printf (file, "%s(decode_table *) %p", prefix, rule);
348   if (rule != NULL)
349     {
350       lf_indent (file, +1);
351       dump_line_ref (file, "\n(line ", rule->line, ")");
352       lf_printf (file, "\n(type %s)", i2name (rule->type, decode_type_map));
353       lf_printf (file, "\n(gen %s)", i2name (rule->gen, decode_gen_map));
354       lf_printf (file, "\n(first %d)", rule->first);
355       lf_printf (file, "\n(last %d)", rule->last);
356       lf_printf (file, "\n(force_first %d)", rule->force_first);
357       lf_printf (file, "\n(force_last %d)", rule->force_last);
358       dump_filter (file, "\n(constant_field_names \"",
359 		   rule->constant_field_names, "\")");
360       lf_printf (file, "\n(constant 0x%x)", rule->constant);
361       lf_printf (file, "\n(word_nr %d)", rule->word_nr);
362       lf_printf (file, "\n(with_zero_reserved %d)", rule->with_zero_reserved);
363       lf_printf (file, "\n(with_duplicates %d)", rule->with_duplicates);
364       lf_printf (file, "\n(with_combine %d)", rule->with_combine);
365       dump_filter (file, "\n(format_names \"", rule->format_names, "\")");
366       dump_filter (file, "\n(model_names \"", rule->model_names, "\")");
367       dump_decode_conds (file, "\n(conditions ", rule->conditions, ")");
368       lf_printf (file, "\n(next %p)", rule->next);
369       lf_indent (file, -1);
370     }
371   lf_printf (file, "%s", suffix);
372 }
373 
374 
375 #ifdef MAIN
376 
377 static void
378 dump_decode_rules (lf *file,
379 		   const char *prefix,
380 		   const decode_table *rule,
381 		   const char *suffix)
382 {
383   lf_printf (file, "%s", prefix);
384   while (rule != NULL)
385     {
386       lf_indent (file, +1);
387       dump_decode_rule (file, "\n(", rule, ")");
388       lf_indent (file, -1);
389       rule = rule->next;
390     }
391   lf_printf (file, "%s", suffix);
392 }
393 
394 igen_options options;
395 
396 int
397 main (int argc, char **argv)
398 {
399   lf *l;
400   decode_table *rules;
401 
402   INIT_OPTIONS ();
403 
404   if (argc != 3)
405     error (NULL, "Usage: decode <decode-file> <hi-bit-nr>\n");
406 
407   options.hi_bit_nr = a2i (argv[2]);
408   rules = load_decode_table (argv[1]);
409   l = lf_open ("-", "stdout", lf_omit_references, lf_is_text, "tmp-ld-insn");
410   dump_decode_rules (l, "(rules ", rules, ")\n");
411 
412   return 0;
413 }
414 #endif
415