1/* opc2c.c --- generate C opcode decoder code from from .opc file
2
3   Copyright (C) 2005, 2007, 2008, 2009 Free Software Foundation, Inc.
4   Contributed by Red Hat, Inc.
5
6   This file is part of the GNU opcode library.
7
8   This program is free software; you can redistribute it and/or modify
9   it under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 3 of the License, or
11   (at your option) any later version.
12
13   This program is distributed in the hope that it will be useful,
14   but WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16   GNU General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
20
21
22#include <stdio.h>
23#include <string.h>
24#include <ctype.h>
25#include <stdlib.h>
26#include <errno.h>
27#include "libiberty.h"
28
29static char * line_buf = NULL;
30static int line_buf_size = 0;
31
32#define LBUFINCR 100
33
34char *
35safe_fgets (FILE * f)
36{
37  char * line_ptr;
38
39  if (line_buf == NULL)
40    {
41      line_buf = (char *) malloc (LBUFINCR);
42      line_buf_size = LBUFINCR;
43    }
44
45  /* Points to last byte.  */
46  line_ptr = line_buf + line_buf_size - 1;
47
48  /* So we can see if fgets put a 0 there.  */
49  *line_ptr = 1;
50  if (fgets (line_buf, line_buf_size, f) == 0)
51    return NULL;
52
53  /* We filled the buffer?  */
54  while (line_ptr[0] == 0 && line_ptr[-1] != '\n')
55    {
56      /* Make the buffer bigger and read more of the line.  */
57      line_buf_size += LBUFINCR;
58      line_buf = (char *) realloc (line_buf, line_buf_size);
59
60      /* Points to last byte again.  */
61      line_ptr = line_buf + line_buf_size - 1;
62      /* So we can see if fgets put a 0 there.  */
63      *line_ptr = 1;
64
65      if (fgets (line_buf + line_buf_size - LBUFINCR - 1, LBUFINCR + 1, f) == 0)
66	return NULL;
67    }
68
69  return line_buf;
70}
71
72
73static int errors = 0;
74
75#define MAX_BYTES 10
76
77typedef struct
78{
79  int varyno:16;
80  int byte:8;
81  int shift:8;
82} VaryRef;
83
84typedef struct
85{
86  char nbytes;
87  char dbytes;
88  char id[MAX_BYTES * 8 + 1];
89  unsigned char var_start[MAX_BYTES * 8 + 1];
90  struct
91  {
92    unsigned char decodable_mask;
93    unsigned char decodable_bits;
94  } b[MAX_BYTES];
95  char * comment;
96  char * syntax;
97  int lineno;
98  int nlines;
99  char ** lines;
100  struct Indirect * last_ind;
101  int semantics_label;
102  int nvaries;
103  VaryRef * vary;
104} opcode;
105
106int n_opcodes;
107opcode ** opcodes;
108opcode * op;
109
110typedef struct
111{
112  char * name;
113  int nlen;
114  unsigned char mask;
115  int n_patterns;
116  unsigned char * patterns;
117} Vary;
118
119Vary ** vary = 0;
120int n_varies = 0;
121
122unsigned char cur_bits[MAX_BYTES + 1];
123
124char * orig_filename;
125
126FILE * sim_log = NULL;
127#define lprintf if (sim_log) fprintf
128
129opcode prefix_text, suffix_text;
130
131typedef enum
132{
133  T_unused,
134  T_op,
135  T_indirect,
136  T_done
137} OpType;
138
139typedef struct Indirect
140{
141  OpType type;
142  union
143  {
144    struct Indirect * ind;
145    opcode * op;
146  } u;
147} Indirect;
148
149Indirect indirect[256];
150
151static int
152next_varybits (int bits, opcode * op, int byte)
153{
154  int mask = op->b[byte].decodable_mask;
155  int i;
156
157  for (i = 0; i < 8; i++)
158    if (!(mask & (1 << i)))
159      {
160	if (bits & (1 << i))
161	  {
162	    bits &= ~(1 << i);
163	  }
164	else
165	  {
166	    bits |= (1 << i);
167	    return bits;
168	  }
169      }
170  return 0;
171}
172
173static int
174valid_varybits (int bits, opcode * op, int byte)
175{
176  if (op->nvaries)
177    {
178      int vn;
179
180      for (vn = 0; vn < op->nvaries; vn++)
181	{
182	  Vary * v;
183	  int found = 0;
184	  int i;
185	  int ob;
186
187	  if (byte != op->vary[vn].byte)
188	    continue;
189	  v = vary[op->vary[vn].varyno];
190	  ob = (bits >> op->vary[vn].shift) & v->mask;
191	  lprintf (sim_log, "varybits: vary %s ob %x\n", v->name, ob);
192
193	  for (i = 0; i < v->n_patterns; i++)
194	    if (ob == v->patterns[i])
195	      {
196		lprintf (sim_log, "  found at %d\n", i);
197		found = 1;
198		break;
199	      }
200	  if (!found)
201	    return 0;
202	}
203    }
204  return 1;
205}
206
207char *
208prmb (int mask, int bits)
209{
210  static char buf[8][30];
211  static int bn = 0;
212  char * bp;
213
214  bn = (bn + 1) % 8;
215  bp = buf[bn];
216  int i;
217  for (i = 0; i < 8; i++)
218    {
219      int bit = 0x80 >> i;
220
221      if (!(mask & bit))
222	*bp++ = '-';
223      else if (bits & bit)
224	*bp++ = '1';
225      else
226	*bp++ = '0';
227      if (i % 4 == 3)
228	*bp++ = ' ';
229    }
230  *--bp = 0;
231  return buf[bn];
232}
233
234static int
235op_cmp (const void *va, const void *vb)
236{
237  const opcode * a = *(const opcode **) va;
238  const opcode * b = *(const opcode **) vb;
239
240  if (a->nbytes != b->nbytes)
241    return a->nbytes - b->nbytes;
242
243  return strcmp (a->id, b->id);
244}
245
246void
247dump_lines (opcode * op, int level, Indirect * ind)
248{
249  char * varnames[40];
250  int i, vn = 0;
251
252  if (op->semantics_label)
253    {
254      printf ("%*sgoto op_semantics_%d;\n", level, "", op->semantics_label);
255      return;
256    }
257
258  if (ind != op->last_ind)
259    {
260      static int labelno = 0;
261      labelno++;
262      printf ("%*sop_semantics_%d:\n", level, "", labelno);
263      op->semantics_label = labelno;
264    }
265
266  if (op->comment)
267    {
268      level += 2;
269      printf ("%*s{\n", level, "");
270      printf ("%*s  %s\n", level, "", op->comment);
271    }
272
273  for (i = 0; i < op->nbytes * 8;)
274    {
275      if (isalpha (op->id[i]))
276	{
277	  int byte = i >> 3;
278	  int mask = 0;
279	  int shift = 0;
280	  char name[33];
281	  char * np = name;
282
283	  while (op->id[i] && isalpha (op->id[i]))
284	    {
285	      mask = (mask << 1) | 1;
286	      shift = 7 - (i & 7);
287	      *np++ = op->id[i++];
288	      if (op->var_start[i])
289		break;
290	    }
291	  *np = 0;
292	  varnames[vn++] = strdup (name);
293	  printf ("#line %d \"%s\"\n", op->lineno + 1, orig_filename);
294	  if (mask & ~0xff)
295	    {
296	      fprintf (stderr, "Error: variable %s spans bytes: %s\n",
297		       name, op->comment);
298	      errors++;
299	    }
300	  else if (shift && (mask != 0xff))
301	    printf ("%*s  int %s AU = (op[%d] >> %d) & 0x%02x;\n",
302		    level, "", name, byte, shift, mask);
303	  else if (mask != 0xff)
304	    printf ("%*s  int %s AU = op[%d] & 0x%02x;\n",
305		    level, "", name, byte, mask);
306	  else
307	    printf ("%*s  int %s AU = op[%d];\n", level, "", name, byte);
308	}
309      else
310	i++;
311    }
312
313  if (op->comment)
314    {
315      printf ("%*s  if (trace)\n", level, "");
316      printf ("%*s    {\n", level, "");
317      printf ("%*s      printf (\"\\033[33m%%s\\033[0m ", level, "");
318      for (i = 0; i < op->nbytes; i++)
319	printf (" %%02x");
320      printf ("\\n\"");
321      printf (",\n%*s             \"%s\"", level, "", op->comment);
322      for (i = 0; i < op->nbytes; i++)
323	{
324	  if (i == 0)
325	    printf (",\n%*s             op[%d]", level, "", i);
326	  else
327	    printf (", op[%d]", i);
328	}
329      printf (");\n");
330      for (i = 0; i < vn; i++)
331	printf ("%*s      printf (\"  %s = 0x%%x%s\", %s);\n", level, "",
332		varnames[i], (i < vn - 1) ? "," : "\\n", varnames[i]);
333      printf ("%*s    }\n", level, "");
334    }
335
336  if (op->syntax)
337    printf ("%*s  SYNTAX(\"%s\");\n", level, "", op->syntax);
338
339  printf ("#line %d \"%s\"\n", op->lineno + 1, orig_filename);
340
341  for (i = 0; i < op->nlines; i++)
342    printf ("%*s%s", level, "", op->lines[i]);
343
344  if (op->comment)
345    printf ("%*s}\n", level, "");
346}
347
348void
349store_opcode_bits (opcode * op, int byte, Indirect * ind)
350{
351  int bits = op->b[byte].decodable_bits;
352
353  do
354    {
355      if (!valid_varybits (bits, op, byte))
356	continue;
357
358      switch (ind[bits].type)
359	{
360	case T_unused:
361	  if (byte == op->dbytes - 1)
362	    {
363	      ind[bits].type = T_op;
364	      ind[bits].u.op = op;
365	      op->last_ind = ind;
366	      break;
367	    }
368	  else
369	    {
370	      int i2;
371
372	      ind[bits].type = T_indirect;
373	      ind[bits].u.ind = (Indirect *) malloc (256 * sizeof (Indirect));
374	      for (i2 = 0; i2 < 256; i2++)
375		ind[bits].u.ind[i2].type = T_unused;
376	      store_opcode_bits (op, byte + 1, ind[bits].u.ind);
377	    }
378	  break;
379
380	case T_indirect:
381	  if (byte < op->dbytes - 1)
382	    store_opcode_bits (op, byte + 1, ind[bits].u.ind);
383	  break;
384
385	case T_op:
386	  break;
387
388	case T_done:
389	  break;
390	}
391    }
392  while ((bits = next_varybits (bits, op, byte)) != 0);
393}
394
395void
396emit_indirect (Indirect * ind, int byte)
397{
398  int unsup = 0;
399  int j, n, mask;
400
401  mask = 0;
402  for (j = 0; j < 256; j++)
403    {
404      switch (ind[j].type)
405	{
406	case T_indirect:
407	  mask = 0xff;
408	  break;
409	case T_op:
410	  mask |= ind[j].u.op->b[byte].decodable_mask;
411	  break;
412	case T_done:
413	case T_unused:
414	  break;
415	}
416    }
417
418  printf ("%*s  GETBYTE ();\n", byte * 6, "");
419  printf ("%*s  switch (op[%d] & 0x%02x)\n", byte * 6, "", byte, mask);
420  printf ("%*s  {\n", byte * 6, "");
421
422  for (j = 0; j < 256; j++)
423    if ((j & ~mask) == 0)
424      {
425	switch (ind[j].type)
426	  {
427	  case T_done:
428	    break;
429	  case T_unused:
430	    unsup = 1;
431	    break;
432	  case T_op:
433	    for (n = j; n < 256; n++)
434	      if ((n & ~mask) == 0
435		  && ind[n].type == T_op && ind[n].u.op == ind[j].u.op)
436		{
437		  ind[n].type = T_done;
438		  printf ("%*s    case 0x%02x:\n", byte * 6, "", n);
439		}
440	    for (n = byte; n < ind[j].u.op->nbytes - 1; n++)
441	      printf ("%*s      GETBYTE();\n", byte * 6, "");
442	    dump_lines (ind[j].u.op, byte * 6 + 6, ind);
443	    printf ("%*s      break;\n", byte * 6, "");
444	    break;
445	  case T_indirect:
446	    printf ("%*s    case 0x%02x:\n", byte * 6, "", j);
447	    emit_indirect (ind[j].u.ind, byte + 1);
448	    printf ("%*s      break;\n", byte * 6, "");
449	    break;
450	  }
451      }
452  if (unsup)
453    printf ("%*s    default: UNSUPPORTED(); break;\n", byte * 6, "");
454  printf ("%*s  }\n", byte * 6, "");
455}
456
457static char *
458pv_dup (char * p, char * ep)
459{
460  int n = ep - p;
461  char *rv = (char *) malloc (n + 1);
462
463  memcpy (rv, p, n);
464  rv[n] = 0;
465  return rv;
466}
467
468static unsigned char
469str2mask (char * str, char * ep)
470{
471  unsigned char rv = 0;
472
473  while (str < ep)
474    {
475      rv *= 2;
476      if (*str == '1')
477	rv += 1;
478      str++;
479    }
480  return rv;
481}
482
483static void
484process_vary (char * line)
485{
486  char * cp;
487  char * ep;
488  Vary * v = (Vary *) malloc (sizeof (Vary));
489
490  n_varies++;
491  if (vary)
492    vary = (Vary **) realloc (vary, n_varies * sizeof (Vary *));
493  else
494    vary = (Vary **) malloc (n_varies * sizeof (Vary *));
495  vary[n_varies - 1] = v;
496
497  cp = line;
498
499  for (cp = line; isspace (*cp); cp++);
500  for (ep = cp; *ep && !isspace (*ep); ep++);
501
502  v->name = pv_dup (cp, ep);
503  v->nlen = strlen (v->name);
504  v->mask = (1 << v->nlen) - 1;
505
506  v->n_patterns = 0;
507  v->patterns = (unsigned char *) malloc (1);
508  while (1)
509    {
510      for (cp = ep; isspace (*cp); cp++);
511      if (!isdigit (*cp))
512	break;
513      for (ep = cp; *ep && !isspace (*ep); ep++);
514      v->n_patterns++;
515      v->patterns = (unsigned char *) realloc (v->patterns, v->n_patterns);
516      v->patterns[v->n_patterns - 1] = str2mask (cp, ep);
517    }
518}
519
520static int
521fieldcmp (opcode * op, int bit, char *name)
522{
523  int n = strlen (name);
524
525  if (memcmp (op->id + bit, name, n) == 0
526      && (!isalpha (op->id[bit + n]) || op->var_start[bit + n]))
527    return 1;
528  return 0;
529}
530
531static void
532log_indirect (Indirect * ind, int byte)
533{
534  int i, j;
535  char * last_c = 0;
536
537  for (i = 0; i < 256; i++)
538    {
539
540      for (j = 0; j < byte; j++)
541	fprintf (sim_log, "%s ", prmb (255, cur_bits[j]));
542      fprintf (sim_log, "%s ", prmb (255, i));
543
544      switch (ind[i].type)
545	{
546	case T_op:
547	case T_done:
548	  if (last_c && (ind[i].u.op->comment == last_c))
549	    fprintf (sim_log, "''\n");
550	  else
551	    fprintf (sim_log, "%s\n", ind[i].u.op->comment);
552	  last_c = ind[i].u.op->comment;
553	  break;
554	case T_unused:
555	  fprintf (sim_log, "unused\n");
556	  break;
557	case T_indirect:
558	  fprintf (sim_log, "indirect\n");
559	  cur_bits[byte] = i;
560	  log_indirect (ind[i].u.ind, byte + 1);
561	  last_c = 0;
562	  break;
563	}
564    }
565}
566
567int
568main (int argc, char ** argv)
569{
570  char * line;
571  FILE * in;
572  int lineno = 0;
573  int i;
574  VaryRef * vlist;
575  int skipping_section = 0;
576
577  if (argc > 2 && strcmp (argv[1], "-l") == 0)
578    {
579      sim_log = fopen (argv[2], "w");
580      fprintf (stderr, "sim_log: %s\n", argv[2]);
581      argc -= 2;
582      argv += 2;
583    }
584
585  if (argc < 2)
586    {
587      fprintf (stderr, "usage: opc2c infile.opc > outfile.opc\n");
588      exit (1);
589    }
590
591  orig_filename = lbasename (argv[1]);
592  in = fopen (argv[1], "r");
593  if (!in)
594    {
595      fprintf (stderr, "Unable to open file %s for reading: %s\n", argv[1],
596	       xstrerror (errno));
597      exit (1);
598    }
599
600  n_opcodes = 0;
601  opcodes = (opcode **) malloc (sizeof (opcode *));
602  op = &prefix_text;
603  op->lineno = 0;
604  while ((line = safe_fgets (in)) != 0)
605    {
606      lineno++;
607      if (strncmp (line, "/*?* ", 5) == 0)
608	{
609	  skipping_section = 1;
610	  continue;
611	}
612      if (strncmp (line, "  /** ", 6) == 0
613	  && (isdigit (line[6]) || memcmp (line + 6, "VARY", 4) == 0))
614	line += 2;
615      if (line[0] == '/' && line[1] == '*' && line[2] == '*')
616	{
617	  skipping_section = 0;
618	  if (strncmp (line, "/** */", 6) == 0)
619	    {
620	      op = &suffix_text;
621	      op->lineno = lineno;
622	    }
623	  else if (strncmp (line, "/** VARY ", 9) == 0)
624	    process_vary (line + 9);
625	  else
626	    {
627	      char * lp;
628	      int i, bit, byte;
629	      int var_start = 1;
630
631	      n_opcodes++;
632	      opcodes =
633		(opcode **) realloc (opcodes, n_opcodes * sizeof (opcode *));
634	      op = (opcode *) malloc (sizeof (opcode));
635	      opcodes[n_opcodes - 1] = op;
636
637	      op->nbytes = op->dbytes = 0;
638	      memset (op->id, 0, sizeof (op->id));
639	      memset (op->var_start, 0, sizeof (op->var_start));
640	      for (i = 0; i < MAX_BYTES; i++)
641		{
642		  op->b[i].decodable_mask = 0;
643		  op->b[i].decodable_bits = 0;
644		}
645	      op->comment = strdup (line);
646	      op->comment[strlen (op->comment) - 1] = 0;
647	      while (op->comment[0] && isspace (op->comment[0]))
648		op->comment++;
649	      op->lineno = lineno;
650	      op->nlines = 0;
651	      op->lines = 0;
652	      op->last_ind = 0;
653	      op->semantics_label = 0;
654	      op->nvaries = 0;
655	      op->vary = 0;
656
657	      i = 0;
658	      for (lp = line + 4; *lp; lp++)
659		{
660		  bit = 7 - (i & 7);
661		  byte = i >> 3;
662
663		  if (strncmp (lp, "*/", 2) == 0)
664		    break;
665		  else if ((lp[0] == ' ' && lp[1] == ' ') || (lp[0] == '\t'))
666		    {
667		      while (*lp == ' ' || *lp == '\t')
668			lp ++;
669		      op->syntax = strdup (lp);
670		      lp = strstr (op->syntax, "*/");
671		      if (lp)
672			{
673			  *lp-- = 0;
674			  while ((*lp == ' ' || *lp == '\t')
675				 && lp > op->syntax)
676			    *lp-- = 0;
677			}
678		      break;
679		    }
680		  else if (*lp == ' ')
681		    var_start = 1;
682		  else
683		    {
684		      if (*lp == '0' || *lp == '1')
685			{
686			  op->b[byte].decodable_mask |= 1 << bit;
687			  var_start = 1;
688			  if (op->dbytes < byte + 1)
689			    op->dbytes = byte + 1;
690			}
691		      else if (var_start)
692			{
693			  op->var_start[i] = 1;
694			  var_start = 0;
695			  if (op->dbytes < byte + 1)
696			    op->dbytes = byte + 1;
697			}
698		      if (*lp == '1')
699			op->b[byte].decodable_bits |= 1 << bit;
700
701		      op->nbytes = byte + 1;
702		      op->id[i++] = *lp;
703		    }
704		}
705	    }
706	}
707      else if (!skipping_section)
708	{
709	  op->nlines++;
710	  if (op->lines)
711	    op->lines =
712	      (char **) realloc (op->lines, op->nlines * sizeof (char *));
713	  else
714	    op->lines = (char **) malloc (op->nlines * sizeof (char *));
715	  op->lines[op->nlines - 1] = strdup (line);
716	}
717    }
718
719  {
720    int i, j;
721    for (i = 0; i < n_varies; i++)
722      {
723	Vary *v = vary[i];
724	lprintf (sim_log, "V[%s] %d\n", v->name, v->nlen);
725	for (j = 0; j < v->n_patterns; j++)
726	  lprintf (sim_log, "  P %02x\n", v->patterns[j]);
727      }
728  }
729
730  for (i = n_opcodes - 2; i >= 0; i--)
731    {
732      if (opcodes[i]->nlines == 0)
733	{
734	  opcodes[i]->nlines = opcodes[i + 1]->nlines;
735	  opcodes[i]->lines = opcodes[i + 1]->lines;
736	}
737    }
738
739  for (i = 0; i < 256; i++)
740    indirect[i].type = T_unused;
741
742  qsort (opcodes, n_opcodes, sizeof (opcodes[0]), op_cmp);
743
744  vlist = (VaryRef *) malloc (n_varies * sizeof (VaryRef));
745
746  for (i = 0; i < n_opcodes; i++)
747    {
748      int j, b, v;
749
750      for (j = 0; j < opcodes[i]->nbytes; j++)
751	lprintf (sim_log, "%s ",
752		 prmb (opcodes[i]->b[j].decodable_mask,
753		       opcodes[i]->b[j].decodable_bits));
754      lprintf (sim_log, " %s\n", opcodes[i]->comment);
755
756      for (j = 0; j < opcodes[i]->nbytes; j++)
757	{
758	  for (b = 0; b < 8; b++)
759	    if (isalpha (opcodes[i]->id[j * 8 + b]))
760	      for (v = 0; v < n_varies; v++)
761		if (fieldcmp (opcodes[i], j * 8 + b, vary[v]->name))
762		  {
763		    int nv = opcodes[i]->nvaries++;
764		    if (nv)
765		      opcodes[i]->vary =
766			(VaryRef *) realloc (opcodes[i]->vary,
767					     (nv + 1) * sizeof (VaryRef));
768		    else
769		      opcodes[i]->vary =
770			(VaryRef *) malloc ((nv + 1) * sizeof (VaryRef));
771
772		    opcodes[i]->vary[nv].varyno = v;
773		    opcodes[i]->vary[nv].byte = j;
774		    opcodes[i]->vary[nv].shift = 8 - b - vary[v]->nlen;
775		    lprintf (sim_log, "[vary %s shift %d]\n",
776			     vary[v]->name, opcodes[i]->vary[nv].shift);
777		  }
778
779	}
780    }
781
782  for (i = 0; i < n_opcodes; i++)
783    {
784      int i2;
785      int bytes = opcodes[i]->dbytes;
786
787      lprintf (sim_log, "\nmask:");
788      for (i2 = 0; i2 < opcodes[i]->nbytes; i2++)
789	lprintf (sim_log, " %02x", opcodes[i]->b[i2].decodable_mask);
790      lprintf (sim_log, "%*s%s\n", 13 - 3 * opcodes[i]->nbytes, "",
791	       opcodes[i]->comment);
792
793      lprintf (sim_log, "bits:");
794      for (i2 = 0; i2 < opcodes[i]->nbytes; i2++)
795	lprintf (sim_log, " %02x", opcodes[i]->b[i2].decodable_bits);
796      lprintf (sim_log, "%*s(%s) %d byte%s\n", 13 - 3 * opcodes[i]->nbytes,
797	       "", opcodes[i]->id, bytes, bytes == 1 ? "" : "s");
798
799      store_opcode_bits (opcodes[i], 0, indirect);
800    }
801
802  dump_lines (&prefix_text, 0, 0);
803
804  emit_indirect (indirect, 0);
805
806  dump_lines (&suffix_text, 0, 0);
807
808  if (sim_log)
809    log_indirect (indirect, 0);
810
811  return errors;
812}
813