aboutsummaryrefslogtreecommitdiff
path: root/sim/igen/gen-semantics.c
blob: 47871ad97174ae74831f91b8e42e54cea664f4db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
/* The IGEN simulator generator for GDB, the GNU Debugger.

   Copyright 2002-2021 Free Software Foundation, Inc.

   Contributed by Andrew Cagney.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */



#include "misc.h"
#include "lf.h"
#include "table.h"
#include "filter.h"
#include "igen.h"

#include "ld-insn.h"
#include "ld-decode.h"

#include "gen.h"

#include "gen-semantics.h"
#include "gen-icache.h"
#include "gen-idecode.h"


static void
print_semantic_function_header (lf *file,
				const char *basename,
				const char *format_name,
				opcode_bits *expanded_bits,
				int is_function_definition,
				int nr_prefetched_words)
{
  int indent;
  lf_printf (file, "\n");
  lf_print__function_type_function (file, print_semantic_function_type,
				    "EXTERN_SEMANTICS",
				    (is_function_definition ? "\n" : " "));
  indent = print_function_name (file,
				basename,
				format_name,
				NULL,
				expanded_bits,
				function_name_prefix_semantics);
  if (is_function_definition)
    {
      indent += lf_printf (file, " ");
      lf_indent (file, +indent);
    }
  else
    {
      lf_printf (file, "\n");
    }
  lf_printf (file, "(");
  lf_indent (file, +1);
  print_semantic_function_formal (file, nr_prefetched_words);
  lf_indent (file, -1);
  lf_printf (file, ")");
  if (is_function_definition)
    {
      lf_indent (file, -indent);
    }
  else
    {
      lf_printf (file, ";");
    }
  lf_printf (file, "\n");
}

void
print_semantic_declaration (lf *file,
			    insn_entry * insn,
			    opcode_bits *expanded_bits,
			    insn_opcodes *opcodes, int nr_prefetched_words)
{
  print_semantic_function_header (file,
				  insn->name,
				  insn->format_name,
				  expanded_bits,
				  0 /* is not function definition */ ,
				  nr_prefetched_words);
}



/* generate the semantics.c file */


void
print_idecode_invalid (lf *file, const char *result, invalid_type type)
{
  const char *name;
  switch (type)
    {
    default:
      name = "unknown";
      break;
    case invalid_illegal:
      name = "illegal";
      break;
    case invalid_fp_unavailable:
      name = "fp_unavailable";
      break;
    case invalid_wrong_slot:
      name = "wrong_slot";
      break;
    }
  if (options.gen.code == generate_jumps)
    {
      lf_printf (file, "goto %s_%s;\n",
		 (options.gen.icache ? "icache" : "semantic"), name);
    }
  else if (options.gen.icache)
    {
      lf_printf (file, "%s %sicache_%s (", result,
		 options.module.global.prefix.l, name);
      print_icache_function_actual (file, 0);
      lf_printf (file, ");\n");
    }
  else
    {
      lf_printf (file, "%s %ssemantic_%s (", result,
		 options.module.global.prefix.l, name);
      print_semantic_function_actual (file, 0);
      lf_printf (file, ");\n");
    }
}


void
print_semantic_body (lf *file,
		     insn_entry * instruction,
		     opcode_bits *expanded_bits, insn_opcodes *opcodes)
{
  /* validate the instruction, if a cache this has already been done */
  if (!options.gen.icache)
    {
      print_idecode_validate (file, instruction, opcodes);
    }

  print_itrace (file, instruction, 0 /*put_value_in_cache */ );

  /* generate the instruction profile call - this is delayed until
     after the instruction has been verified.  The count macro
     generated is prefixed by ITABLE_PREFIX */
  {
    lf_printf (file, "\n");
    lf_indent_suppress (file);
    lf_printf (file, "#if defined (%sPROFILE_COUNT_INSN)\n",
	       options.module.itable.prefix.u);
    lf_printf (file, "%sPROFILE_COUNT_INSN (CPU, CIA, MY_INDEX);\n",
	       options.module.itable.prefix.u);
    lf_indent_suppress (file);
    lf_printf (file, "#endif\n");
  }

  /* generate the model call - this is delayed until after the
     instruction has been verified */
  {
    lf_printf (file, "\n");
    lf_indent_suppress (file);
    lf_printf (file, "#if defined (WITH_MON)\n");
    lf_printf (file, "/* monitoring: */\n");
    lf_printf (file, "if (WITH_MON & MONITOR_INSTRUCTION_ISSUE)\n");
    lf_printf (file, "  mon_issue (");
    print_function_name (file,
			 instruction->name,
			 instruction->format_name,
			 NULL, NULL, function_name_prefix_itable);
    lf_printf (file, ", cpu, cia);\n");
    lf_indent_suppress (file);
    lf_printf (file, "#endif\n");
    lf_printf (file, "\n");
  }

  /* determine the new instruction address */
  {
    lf_printf (file, "/* keep the next instruction address handy */\n");
    if (options.gen.nia == nia_is_invalid)
      {
	lf_printf (file, "nia = %sINVALID_INSTRUCTION_ADDRESS;\n",
		   options.module.global.prefix.u);
      }
    else
      {
	int nr_immeds = instruction->nr_words - 1;
	if (options.gen.delayed_branch)
	  {
	    if (nr_immeds > 0)
	      {
		lf_printf (file, "cia.dp += %d * %d; %s\n",
			   options.insn_bit_size / 8, nr_immeds,
			   "/* skip dp immeds */");
	      }
	    lf_printf (file, "nia.ip = cia.dp; %s\n",
		       "/* instruction pointer */");
	    lf_printf (file, "nia.dp = cia.dp + %d; %s\n",
		       options.insn_bit_size / 8,
		       "/* delayed-slot pointer */");
	  }
	else
	  {
	    if (nr_immeds > 0)
	      {
		lf_printf (file, "nia = cia + %d * (%d + 1); %s\n",
			   options.insn_bit_size / 8, nr_immeds,
			   "/* skip immeds as well */");

	      }
	    else
	      {
		lf_printf (file, "nia = cia + %d;\n",
			   options.insn_bit_size / 8);
	      }
	  }
      }
  }

  /* if conditional, generate code to verify that the instruction
     should be issued */
  if (filter_is_member (instruction->options, "c")
      || options.gen.conditional_issue)
    {
      lf_printf (file, "\n");
      lf_printf (file, "/* execute only if conditional passes */\n");
      lf_printf (file, "if (IS_CONDITION_OK)\n");
      lf_printf (file, "  {\n");
      lf_indent (file, +4);
      /* FIXME - need to log a conditional failure */
    }

  /* Architecture expects a REG to be zero.  Instead of having to
     check every read to see if it is refering to that REG just zap it
     at the start of every instruction */
  if (options.gen.zero_reg)
    {
      lf_printf (file, "\n");
      lf_printf (file, "/* Architecture expects REG to be zero */\n");
      lf_printf (file, "GPR_CLEAR(%d);\n", options.gen.zero_reg_nr);
    }

  /* generate the code (or at least something */
  lf_printf (file, "\n");
  lf_printf (file, "/* semantics: */\n");
  if (instruction->code != NULL)
    {
      /* true code */
      lf_printf (file, "{\n");
      lf_indent (file, +2);
      lf_print__line_ref (file, instruction->code->line);
      table_print_code (file, instruction->code);
      lf_indent (file, -2);
      lf_printf (file, "}\n");
      lf_print__internal_ref (file);
    }
  else if (filter_is_member (instruction->options, "nop"))
    {
      lf_print__internal_ref (file);
    }
  else
    {
      const char *prefix = "sim_engine_abort (";
      int indent = strlen (prefix);
      /* abort so it is implemented now */
      lf_print__line_ref (file, instruction->line);
      lf_printf (file, "%sSD, CPU, cia, \\\n", prefix);
      lf_indent (file, +indent);
      lf_printf (file, "\"%s:%d:0x%%08lx:%%s unimplemented\\n\", \\\n",
		 filter_filename (instruction->line->file_name),
		 instruction->line->line_nr);
      lf_printf (file, "(long) CIA, \\\n");
      lf_printf (file, "%sitable[MY_INDEX].name);\n",
		 options.module.itable.prefix.l);
      lf_indent (file, -indent);
      lf_print__internal_ref (file);
    }

  /* Close off the conditional execution */
  if (filter_is_member (instruction->options, "c")
      || options.gen.conditional_issue)
    {
      lf_indent (file, -4);
      lf_printf (file, "  }\n");
    }
}

static void
print_c_semantic (lf *file,
		  insn_entry * instruction,
		  opcode_bits *expanded_bits,
		  insn_opcodes *opcodes,
		  cache_entry *cache_rules, int nr_prefetched_words)
{

  lf_printf (file, "{\n");
  lf_indent (file, +2);

  print_my_defines (file,
		    instruction->name,
		    instruction->format_name, expanded_bits);
  lf_printf (file, "\n");
  print_icache_body (file,
		     instruction,
		     expanded_bits,
		     cache_rules,
		     (options.gen.direct_access
		      ? define_variables
		      : declare_variables),
		     (options.gen.icache
		      ? get_values_from_icache
		      : do_not_use_icache), nr_prefetched_words);

  lf_printf (file, "%sinstruction_address nia;\n",
	     options.module.global.prefix.l);
  print_semantic_body (file, instruction, expanded_bits, opcodes);
  lf_printf (file, "return nia;\n");

  /* generate something to clean up any #defines created for the cache */
  if (options.gen.direct_access)
    {
      print_icache_body (file,
			 instruction,
			 expanded_bits,
			 cache_rules,
			 undef_variables,
			 (options.gen.icache
			  ? get_values_from_icache
			  : do_not_use_icache), nr_prefetched_words);
    }

  lf_indent (file, -2);
  lf_printf (file, "}\n");
}

static void
print_c_semantic_function (lf *file,
			   insn_entry * instruction,
			   opcode_bits *expanded_bits,
			   insn_opcodes *opcodes,
			   cache_entry *cache_rules, int nr_prefetched_words)
{
  /* build the semantic routine to execute the instruction */
  print_semantic_function_header (file,
				  instruction->name,
				  instruction->format_name,
				  expanded_bits,
				  1 /*is-function-definition */ ,
				  nr_prefetched_words);
  print_c_semantic (file,
		    instruction,
		    expanded_bits, opcodes, cache_rules, nr_prefetched_words);
}

void
print_semantic_definition (lf *file,
			   insn_entry * insn,
			   opcode_bits *expanded_bits,
			   insn_opcodes *opcodes,
			   cache_entry *cache_rules, int nr_prefetched_words)
{
  print_c_semantic_function (file,
			     insn,
			     expanded_bits,
			     opcodes, cache_rules, nr_prefetched_words);
}