1 /* itbl-ops.c
2    Copyright 1997, 1999, 2000, 2001, 2002, 2003, 2005
3    Free Software Foundation, Inc.
4 
5    This file is part of GAS, the GNU Assembler.
6 
7    GAS is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 2, or (at your option)
10    any later version.
11 
12    GAS is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with GAS; see the file COPYING.  If not, write to the Free
19    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
20    02110-1301, USA.  */
21 
22 /*======================================================================*/
23 /*
24  * Herein lies the support for dynamic specification of processor
25  * instructions and registers.  Mnemonics, values, and formats for each
26  * instruction and register are specified in an ascii file consisting of
27  * table entries.  The grammar for the table is defined in the document
28  * "Processor instruction table specification".
29  *
30  * Instructions use the gnu assembler syntax, with the addition of
31  * allowing mnemonics for register.
32  * Eg. "func $2,reg3,0x100,symbol ; comment"
33  * 	func - opcode name
34  * 	$n - register n
35  * 	reg3 - mnemonic for processor's register defined in table
36  * 	0xddd..d - immediate value
37  * 	symbol - address of label or external symbol
38  *
39  * First, itbl_parse reads in the table of register and instruction
40  * names and formats, and builds a list of entries for each
41  * processor/type combination.  lex and yacc are used to parse
42  * the entries in the table and call functions defined here to
43  * add each entry to our list.
44  *
45  * Then, when assembling or disassembling, these functions are called to
46  * 1) get information on a processor's registers and
47  * 2) assemble/disassemble an instruction.
48  * To assemble(disassemble) an instruction, the function
49  * itbl_assemble(itbl_disassemble) is called to search the list of
50  * instruction entries, and if a match is found, uses the format
51  * described in the instruction entry structure to complete the action.
52  *
53  * Eg. Suppose we have a Mips coprocessor "cop3" with data register "d2"
54  * and we want to define function "pig" which takes two operands.
55  *
56  * Given the table entries:
57  * 	"p3 insn pig 0x1:24-21 dreg:20-16 immed:15-0"
58  * 	"p3 dreg d2 0x2"
59  * and that the instruction encoding for coprocessor pz has encoding:
60  * 	#define MIPS_ENCODE_COP_NUM(z) ((0x21|(z<<1))<<25)
61  * 	#define ITBL_ENCODE_PNUM(pnum) MIPS_ENCODE_COP_NUM(pnum)
62  *
63  * a structure to describe the instruction might look something like:
64  *      struct itbl_entry = {
65  *      e_processor processor = e_p3
66  *      e_type type = e_insn
67  *      char *name = "pig"
68  *      uint value = 0x1
69  *      uint flags = 0
70  *      struct itbl_range range = 24-21
71  *      struct itbl_field *field = {
72  *              e_type type = e_dreg
73  *              struct itbl_range range = 20-16
74  *              struct itbl_field *next = {
75  *                      e_type type = e_immed
76  *                      struct itbl_range range = 15-0
77  *                      struct itbl_field *next = 0
78  *                      };
79  *              };
80  *      struct itbl_entry *next = 0
81  *      };
82  *
83  * And the assembler instructions:
84  * 	"pig d2,0x100"
85  * 	"pig $2,0x100"
86  *
87  * would both assemble to the hex value:
88  * 	"0x4e220100"
89  *
90  */
91 
92 #include <stdio.h>
93 #include <stdlib.h>
94 #include <string.h>
95 #include "itbl-ops.h"
96 #include <itbl-parse.h>
97 
98 /* #define DEBUG */
99 
100 #ifdef DEBUG
101 #include <assert.h>
102 #define ASSERT(x) assert(x)
103 #define DBG(x) printf x
104 #else
105 #define ASSERT(x)
106 #define DBG(x)
107 #endif
108 
109 #ifndef min
110 #define min(a,b) (a<b?a:b)
111 #endif
112 
113 int itbl_have_entries = 0;
114 
115 /*======================================================================*/
116 /* structures for keeping itbl format entries */
117 
118 struct itbl_range {
119   int sbit;			/* mask starting bit position */
120   int ebit;			/* mask ending bit position */
121 };
122 
123 struct itbl_field {
124   e_type type;			/* dreg/creg/greg/immed/symb */
125   struct itbl_range range;	/* field's bitfield range within instruction */
126   unsigned long flags;		/* field flags */
127   struct itbl_field *next;	/* next field in list */
128 };
129 
130 /* These structures define the instructions and registers for a processor.
131  * If the type is an instruction, the structure defines the format of an
132  * instruction where the fields are the list of operands.
133  * The flags field below uses the same values as those defined in the
134  * gnu assembler and are machine specific.  */
135 struct itbl_entry {
136   e_processor processor;	/* processor number */
137   e_type type;			/* dreg/creg/greg/insn */
138   char *name;			/* mnemionic name for insn/register */
139   unsigned long value;		/* opcode/instruction mask/register number */
140   unsigned long flags;		/* effects of the instruction */
141   struct itbl_range range;	/* bit range within instruction for value */
142   struct itbl_field *fields;	/* list of operand definitions (if any) */
143   struct itbl_entry *next;	/* next entry */
144 };
145 
146 /* local data and structures */
147 
148 static int itbl_num_opcodes = 0;
149 /* Array of entries for each processor and entry type */
150 static struct itbl_entry *entries[e_nprocs][e_ntypes] = {
151   {0, 0, 0, 0, 0, 0},
152   {0, 0, 0, 0, 0, 0},
153   {0, 0, 0, 0, 0, 0},
154   {0, 0, 0, 0, 0, 0}
155 };
156 
157 /* local prototypes */
158 static unsigned long build_opcode (struct itbl_entry *e);
159 static e_type get_type (int yytype);
160 static e_processor get_processor (int yyproc);
161 static struct itbl_entry **get_entries (e_processor processor,
162 					e_type type);
163 static struct itbl_entry *find_entry_byname (e_processor processor,
164 					e_type type, char *name);
165 static struct itbl_entry *find_entry_byval (e_processor processor,
166 			e_type type, unsigned long val, struct itbl_range *r);
167 static struct itbl_entry *alloc_entry (e_processor processor,
168 		e_type type, char *name, unsigned long value);
169 static unsigned long apply_range (unsigned long value, struct itbl_range r);
170 static unsigned long extract_range (unsigned long value, struct itbl_range r);
171 static struct itbl_field *alloc_field (e_type type, int sbit,
172 					int ebit, unsigned long flags);
173 
174 /*======================================================================*/
175 /* Interfaces to the parser */
176 
177 /* Open the table and use lex and yacc to parse the entries.
178  * Return 1 for failure; 0 for success.  */
179 
180 int
itbl_parse(char * insntbl)181 itbl_parse (char *insntbl)
182 {
183   extern FILE *yyin;
184   extern int yyparse (void);
185 
186   yyin = fopen (insntbl, FOPEN_RT);
187   if (yyin == 0)
188     {
189       printf ("Can't open processor instruction specification file \"%s\"\n",
190 	      insntbl);
191       return 1;
192     }
193 
194   while (yyparse ())
195     ;
196 
197   fclose (yyin);
198   itbl_have_entries = 1;
199   return 0;
200 }
201 
202 /* Add a register entry */
203 
204 struct itbl_entry *
itbl_add_reg(int yyprocessor,int yytype,char * regname,int regnum)205 itbl_add_reg (int yyprocessor, int yytype, char *regname,
206 	      int regnum)
207 {
208   return alloc_entry (get_processor (yyprocessor), get_type (yytype), regname,
209 		      (unsigned long) regnum);
210 }
211 
212 /* Add an instruction entry */
213 
214 struct itbl_entry *
itbl_add_insn(int yyprocessor,char * name,unsigned long value,int sbit,int ebit,unsigned long flags)215 itbl_add_insn (int yyprocessor, char *name, unsigned long value,
216 	       int sbit, int ebit, unsigned long flags)
217 {
218   struct itbl_entry *e;
219   e = alloc_entry (get_processor (yyprocessor), e_insn, name, value);
220   if (e)
221     {
222       e->range.sbit = sbit;
223       e->range.ebit = ebit;
224       e->flags = flags;
225       itbl_num_opcodes++;
226     }
227   return e;
228 }
229 
230 /* Add an operand to an instruction entry */
231 
232 struct itbl_field *
itbl_add_operand(struct itbl_entry * e,int yytype,int sbit,int ebit,unsigned long flags)233 itbl_add_operand (struct itbl_entry *e, int yytype, int sbit,
234 		  int ebit, unsigned long flags)
235 {
236   struct itbl_field *f, **last_f;
237   if (!e)
238     return 0;
239   /* Add to end of fields' list.  */
240   f = alloc_field (get_type (yytype), sbit, ebit, flags);
241   if (f)
242     {
243       last_f = &e->fields;
244       while (*last_f)
245 	last_f = &(*last_f)->next;
246       *last_f = f;
247       f->next = 0;
248     }
249   return f;
250 }
251 
252 /*======================================================================*/
253 /* Interfaces for assembler and disassembler */
254 
255 #ifndef STAND_ALONE
256 #include "as.h"
257 #include "symbols.h"
258 static void append_insns_as_macros (void);
259 
260 /* Initialize for gas.  */
261 
262 void
itbl_init(void)263 itbl_init (void)
264 {
265   struct itbl_entry *e, **es;
266   e_processor procn;
267   e_type type;
268 
269   if (!itbl_have_entries)
270     return;
271 
272   /* Since register names don't have a prefix, put them in the symbol table so
273      they can't be used as symbols.  This simplifies argument parsing as
274      we can let gas parse registers for us.  */
275   /* Use symbol_create instead of symbol_new so we don't try to
276      output registers into the object file's symbol table.  */
277 
278   for (type = e_regtype0; type < e_nregtypes; type++)
279     for (procn = e_p0; procn < e_nprocs; procn++)
280       {
281 	es = get_entries (procn, type);
282 	for (e = *es; e; e = e->next)
283 	  {
284 	    symbol_table_insert (symbol_create (e->name, reg_section,
285 						e->value, &zero_address_frag));
286 	  }
287       }
288   append_insns_as_macros ();
289 }
290 
291 /* Append insns to opcodes table and increase number of opcodes
292  * Structure of opcodes table:
293  * struct itbl_opcode
294  * {
295  *   const char *name;
296  *   const char *args; 		- string describing the arguments.
297  *   unsigned long match; 	- opcode, or ISA level if pinfo=INSN_MACRO
298  *   unsigned long mask; 	- opcode mask, or macro id if pinfo=INSN_MACRO
299  *   unsigned long pinfo; 	- insn flags, or INSN_MACRO
300  * };
301  * examples:
302  *	{"li",      "t,i",  0x34000000, 0xffe00000, WR_t    },
303  *	{"li",      "t,I",  0,    (int) M_LI,   INSN_MACRO  },
304  */
305 
306 static char *form_args (struct itbl_entry *e);
307 static void
append_insns_as_macros(void)308 append_insns_as_macros (void)
309 {
310   struct ITBL_OPCODE_STRUCT *new_opcodes, *o;
311   struct itbl_entry *e, **es;
312   int n, id, size, new_size, new_num_opcodes;
313 
314   if (!itbl_have_entries)
315     return;
316 
317   if (!itbl_num_opcodes)	/* no new instructions to add! */
318     {
319       return;
320     }
321   DBG (("previous num_opcodes=%d\n", ITBL_NUM_OPCODES));
322 
323   new_num_opcodes = ITBL_NUM_OPCODES + itbl_num_opcodes;
324   ASSERT (new_num_opcodes >= itbl_num_opcodes);
325 
326   size = sizeof (struct ITBL_OPCODE_STRUCT) * ITBL_NUM_OPCODES;
327   ASSERT (size >= 0);
328   DBG (("I get=%d\n", size / sizeof (ITBL_OPCODES[0])));
329 
330   new_size = sizeof (struct ITBL_OPCODE_STRUCT) * new_num_opcodes;
331   ASSERT (new_size > size);
332 
333   /* FIXME since ITBL_OPCODES culd be a static table,
334 		we can't realloc or delete the old memory.  */
335   new_opcodes = (struct ITBL_OPCODE_STRUCT *) malloc (new_size);
336   if (!new_opcodes)
337     {
338       printf (_("Unable to allocate memory for new instructions\n"));
339       return;
340     }
341   if (size)			/* copy preexisting opcodes table */
342     memcpy (new_opcodes, ITBL_OPCODES, size);
343 
344   /* FIXME! some NUMOPCODES are calculated expressions.
345 		These need to be changed before itbls can be supported.  */
346 
347   id = ITBL_NUM_MACROS;		/* begin the next macro id after the last */
348   o = &new_opcodes[ITBL_NUM_OPCODES];	/* append macro to opcodes list */
349   for (n = e_p0; n < e_nprocs; n++)
350     {
351       es = get_entries (n, e_insn);
352       for (e = *es; e; e = e->next)
353 	{
354 	  /* name,    args,   mask,       match,  pinfo
355 		 * {"li",      "t,i",  0x34000000, 0xffe00000, WR_t    },
356 		 * {"li",      "t,I",  0,    (int) M_LI,   INSN_MACRO  },
357 		 * Construct args from itbl_fields.
358 		*/
359 	  o->name = e->name;
360 	  o->args = strdup (form_args (e));
361 	  o->mask = apply_range (e->value, e->range);
362 	  /* FIXME how to catch during assembly? */
363 	  /* mask to identify this insn */
364 	  o->match = apply_range (e->value, e->range);
365 	  o->pinfo = 0;
366 
367 #ifdef USE_MACROS
368 	  o->mask = id++;	/* FIXME how to catch during assembly? */
369 	  o->match = 0;		/* for macros, the insn_isa number */
370 	  o->pinfo = INSN_MACRO;
371 #endif
372 
373 	  /* Don't add instructions which caused an error */
374 	  if (o->args)
375 	    o++;
376 	  else
377 	    new_num_opcodes--;
378 	}
379     }
380   ITBL_OPCODES = new_opcodes;
381   ITBL_NUM_OPCODES = new_num_opcodes;
382 
383   /* FIXME
384 		At this point, we can free the entries, as they should have
385 		been added to the assembler's tables.
386 		Don't free name though, since name is being used by the new
387 		opcodes table.
388 
389 		Eventually, we should also free the new opcodes table itself
390 		on exit.
391 	*/
392 }
393 
394 static char *
form_args(struct itbl_entry * e)395 form_args (struct itbl_entry *e)
396 {
397   static char s[31];
398   char c = 0, *p = s;
399   struct itbl_field *f;
400 
401   ASSERT (e);
402   for (f = e->fields; f; f = f->next)
403     {
404       switch (f->type)
405 	{
406 	case e_dreg:
407 	  c = 'd';
408 	  break;
409 	case e_creg:
410 	  c = 't';
411 	  break;
412 	case e_greg:
413 	  c = 's';
414 	  break;
415 	case e_immed:
416 	  c = 'i';
417 	  break;
418 	case e_addr:
419 	  c = 'a';
420 	  break;
421 	default:
422 	  c = 0;		/* ignore; unknown field type */
423 	}
424       if (c)
425 	{
426 	  if (p != s)
427 	    *p++ = ',';
428 	  *p++ = c;
429 	}
430     }
431   *p = 0;
432   return s;
433 }
434 #endif /* !STAND_ALONE */
435 
436 /* Get processor's register name from val */
437 
438 int
itbl_get_reg_val(char * name,unsigned long * pval)439 itbl_get_reg_val (char *name, unsigned long *pval)
440 {
441   e_type t;
442   e_processor p;
443 
444   for (p = e_p0; p < e_nprocs; p++)
445     {
446       for (t = e_regtype0; t < e_nregtypes; t++)
447 	{
448 	  if (itbl_get_val (p, t, name, pval))
449 	    return 1;
450 	}
451     }
452   return 0;
453 }
454 
455 char *
itbl_get_name(e_processor processor,e_type type,unsigned long val)456 itbl_get_name (e_processor processor, e_type type, unsigned long val)
457 {
458   struct itbl_entry *r;
459   /* type depends on instruction passed */
460   r = find_entry_byval (processor, type, val, 0);
461   if (r)
462     return r->name;
463   else
464     return 0;			/* error; invalid operand */
465 }
466 
467 /* Get processor's register value from name */
468 
469 int
itbl_get_val(e_processor processor,e_type type,char * name,unsigned long * pval)470 itbl_get_val (e_processor processor, e_type type, char *name,
471 	      unsigned long *pval)
472 {
473   struct itbl_entry *r;
474   /* type depends on instruction passed */
475   r = find_entry_byname (processor, type, name);
476   if (r == NULL)
477     return 0;
478   *pval = r->value;
479   return 1;
480 }
481 
482 /* Assemble instruction "name" with operands "s".
483  * name - name of instruction
484  * s - operands
485  * returns - long word for assembled instruction */
486 
487 unsigned long
itbl_assemble(char * name,char * s)488 itbl_assemble (char *name, char *s)
489 {
490   unsigned long opcode;
491   struct itbl_entry *e = NULL;
492   struct itbl_field *f;
493   char *n;
494   int processor;
495 
496   if (!name || !*name)
497     return 0;			/* error!  must have an opcode name/expr */
498 
499   /* find entry in list of instructions for all processors */
500   for (processor = 0; processor < e_nprocs; processor++)
501     {
502       e = find_entry_byname (processor, e_insn, name);
503       if (e)
504 	break;
505     }
506   if (!e)
507     return 0;			/* opcode not in table; invalid instruction */
508   opcode = build_opcode (e);
509 
510   /* parse opcode's args (if any) */
511   for (f = e->fields; f; f = f->next)	/* for each arg, ...  */
512     {
513       struct itbl_entry *r;
514       unsigned long value;
515       if (!s || !*s)
516 	return 0;		/* error - not enough operands */
517       n = itbl_get_field (&s);
518       /* n should be in form $n or 0xhhh (are symbol names valid?? */
519       switch (f->type)
520 	{
521 	case e_dreg:
522 	case e_creg:
523 	case e_greg:
524 	  /* Accept either a string name
525 			 * or '$' followed by the register number */
526 	  if (*n == '$')
527 	    {
528 	      n++;
529 	      value = strtol (n, 0, 10);
530 	      /* FIXME! could have "0l"... then what?? */
531 	      if (value == 0 && *n != '0')
532 		return 0;	/* error; invalid operand */
533 	    }
534 	  else
535 	    {
536 	      r = find_entry_byname (e->processor, f->type, n);
537 	      if (r)
538 		value = r->value;
539 	      else
540 		return 0;	/* error; invalid operand */
541 	    }
542 	  break;
543 	case e_addr:
544 	  /* use assembler's symbol table to find symbol */
545 	  /* FIXME!! Do we need this?
546 				if so, what about relocs??
547 				my_getExpression (&imm_expr, s);
548 				return 0;	/-* error; invalid operand *-/
549 				break;
550 			*/
551 	  /* If not a symbol, fall thru to IMMED */
552 	case e_immed:
553 	  if (*n == '0' && *(n + 1) == 'x')	/* hex begins 0x...  */
554 	    {
555 	      n += 2;
556 	      value = strtol (n, 0, 16);
557 	      /* FIXME! could have "0xl"... then what?? */
558 	    }
559 	  else
560 	    {
561 	      value = strtol (n, 0, 10);
562 	      /* FIXME! could have "0l"... then what?? */
563 	      if (value == 0 && *n != '0')
564 		return 0;	/* error; invalid operand */
565 	    }
566 	  break;
567 	default:
568 	  return 0;		/* error; invalid field spec */
569 	}
570       opcode |= apply_range (value, f->range);
571     }
572   if (s && *s)
573     return 0;			/* error - too many operands */
574   return opcode;		/* done! */
575 }
576 
577 /* Disassemble instruction "insn".
578  * insn - instruction
579  * s - buffer to hold disassembled instruction
580  * returns - 1 if succeeded; 0 if failed
581  */
582 
583 int
itbl_disassemble(char * s,unsigned long insn)584 itbl_disassemble (char *s, unsigned long insn)
585 {
586   e_processor processor;
587   struct itbl_entry *e;
588   struct itbl_field *f;
589 
590   if (!ITBL_IS_INSN (insn))
591     return 0;			/* error */
592   processor = get_processor (ITBL_DECODE_PNUM (insn));
593 
594   /* find entry in list */
595   e = find_entry_byval (processor, e_insn, insn, 0);
596   if (!e)
597     return 0;			/* opcode not in table; invalid instruction */
598   strcpy (s, e->name);
599 
600   /* Parse insn's args (if any).  */
601   for (f = e->fields; f; f = f->next)	/* for each arg, ...  */
602     {
603       struct itbl_entry *r;
604       unsigned long value;
605 
606       if (f == e->fields)	/* First operand is preceded by tab.  */
607 	strcat (s, "\t");
608       else			/* ','s separate following operands.  */
609 	strcat (s, ",");
610       value = extract_range (insn, f->range);
611       /* n should be in form $n or 0xhhh (are symbol names valid?? */
612       switch (f->type)
613 	{
614 	case e_dreg:
615 	case e_creg:
616 	case e_greg:
617 	  /* Accept either a string name
618 	     or '$' followed by the register number.  */
619 	  r = find_entry_byval (e->processor, f->type, value, &f->range);
620 	  if (r)
621 	    strcat (s, r->name);
622 	  else
623 	    sprintf (s, "%s$%lu", s, value);
624 	  break;
625 	case e_addr:
626 	  /* Use assembler's symbol table to find symbol.  */
627 	  /* FIXME!! Do we need this?  If so, what about relocs??  */
628 	  /* If not a symbol, fall through to IMMED.  */
629 	case e_immed:
630 	  sprintf (s, "%s0x%lx", s, value);
631 	  break;
632 	default:
633 	  return 0;		/* error; invalid field spec */
634 	}
635     }
636   return 1;			/* Done!  */
637 }
638 
639 /*======================================================================*/
640 /*
641  * Local functions for manipulating private structures containing
642  * the names and format for the new instructions and registers
643  * for each processor.
644  */
645 
646 /* Calculate instruction's opcode and function values from entry */
647 
648 static unsigned long
build_opcode(struct itbl_entry * e)649 build_opcode (struct itbl_entry *e)
650 {
651   unsigned long opcode;
652 
653   opcode = apply_range (e->value, e->range);
654   opcode |= ITBL_ENCODE_PNUM (e->processor);
655   return opcode;
656 }
657 
658 /* Calculate absolute value given the relative value and bit position range
659  * within the instruction.
660  * The range is inclusive where 0 is least significant bit.
661  * A range of { 24, 20 } will have a mask of
662  * bit   3           2            1
663  * pos: 1098 7654 3210 9876 5432 1098 7654 3210
664  * bin: 0000 0001 1111 0000 0000 0000 0000 0000
665  * hex:    0    1    f    0    0    0    0    0
666  * mask: 0x01f00000.
667  */
668 
669 static unsigned long
apply_range(unsigned long rval,struct itbl_range r)670 apply_range (unsigned long rval, struct itbl_range r)
671 {
672   unsigned long mask;
673   unsigned long aval;
674   int len = MAX_BITPOS - r.sbit;
675 
676   ASSERT (r.sbit >= r.ebit);
677   ASSERT (MAX_BITPOS >= r.sbit);
678   ASSERT (r.ebit >= 0);
679 
680   /* create mask by truncating 1s by shifting */
681   mask = 0xffffffff << len;
682   mask = mask >> len;
683   mask = mask >> r.ebit;
684   mask = mask << r.ebit;
685 
686   aval = (rval << r.ebit) & mask;
687   return aval;
688 }
689 
690 /* Calculate relative value given the absolute value and bit position range
691  * within the instruction.  */
692 
693 static unsigned long
extract_range(unsigned long aval,struct itbl_range r)694 extract_range (unsigned long aval, struct itbl_range r)
695 {
696   unsigned long mask;
697   unsigned long rval;
698   int len = MAX_BITPOS - r.sbit;
699 
700   /* create mask by truncating 1s by shifting */
701   mask = 0xffffffff << len;
702   mask = mask >> len;
703   mask = mask >> r.ebit;
704   mask = mask << r.ebit;
705 
706   rval = (aval & mask) >> r.ebit;
707   return rval;
708 }
709 
710 /* Extract processor's assembly instruction field name from s;
711  * forms are "n args" "n,args" or "n" */
712 /* Return next argument from string pointer "s" and advance s.
713  * delimiters are " ,()" */
714 
715 char *
itbl_get_field(char ** S)716 itbl_get_field (char **S)
717 {
718   static char n[128];
719   char *s;
720   int len;
721 
722   s = *S;
723   if (!s || !*s)
724     return 0;
725   /* FIXME: This is a weird set of delimiters.  */
726   len = strcspn (s, " \t,()");
727   ASSERT (128 > len + 1);
728   strncpy (n, s, len);
729   n[len] = 0;
730   if (s[len] == '\0')
731     s = 0;			/* no more args */
732   else
733     s += len + 1;		/* advance to next arg */
734 
735   *S = s;
736   return n;
737 }
738 
739 /* Search entries for a given processor and type
740  * to find one matching the name "n".
741  * Return a pointer to the entry */
742 
743 static struct itbl_entry *
find_entry_byname(e_processor processor,e_type type,char * n)744 find_entry_byname (e_processor processor,
745 		   e_type type, char *n)
746 {
747   struct itbl_entry *e, **es;
748 
749   es = get_entries (processor, type);
750   for (e = *es; e; e = e->next)	/* for each entry, ...  */
751     {
752       if (!strcmp (e->name, n))
753 	return e;
754     }
755   return 0;
756 }
757 
758 /* Search entries for a given processor and type
759  * to find one matching the value "val" for the range "r".
760  * Return a pointer to the entry.
761  * This function is used for disassembling fields of an instruction.
762  */
763 
764 static struct itbl_entry *
find_entry_byval(e_processor processor,e_type type,unsigned long val,struct itbl_range * r)765 find_entry_byval (e_processor processor, e_type type,
766 		  unsigned long val, struct itbl_range *r)
767 {
768   struct itbl_entry *e, **es;
769   unsigned long eval;
770 
771   es = get_entries (processor, type);
772   for (e = *es; e; e = e->next)	/* for each entry, ...  */
773     {
774       if (processor != e->processor)
775 	continue;
776       /* For insns, we might not know the range of the opcode,
777 	 * so a range of 0 will allow this routine to match against
778 	 * the range of the entry to be compared with.
779 	 * This could cause ambiguities.
780 	 * For operands, we get an extracted value and a range.
781 	 */
782       /* if range is 0, mask val against the range of the compared entry.  */
783       if (r == 0)		/* if no range passed, must be whole 32-bits
784 			 * so create 32-bit value from entry's range */
785 	{
786 	  eval = apply_range (e->value, e->range);
787 	  val &= apply_range (0xffffffff, e->range);
788 	}
789       else if ((r->sbit == e->range.sbit && r->ebit == e->range.ebit)
790 	       || (e->range.sbit == 0 && e->range.ebit == 0))
791 	{
792 	  eval = apply_range (e->value, *r);
793 	  val = apply_range (val, *r);
794 	}
795       else
796 	continue;
797       if (val == eval)
798 	return e;
799     }
800   return 0;
801 }
802 
803 /* Return a pointer to the list of entries for a given processor and type.  */
804 
805 static struct itbl_entry **
get_entries(e_processor processor,e_type type)806 get_entries (e_processor processor, e_type type)
807 {
808   return &entries[processor][type];
809 }
810 
811 /* Return an integral value for the processor passed from yyparse.  */
812 
813 static e_processor
get_processor(int yyproc)814 get_processor (int yyproc)
815 {
816   /* translate from yacc's processor to enum */
817   if (yyproc >= e_p0 && yyproc < e_nprocs)
818     return (e_processor) yyproc;
819   return e_invproc;		/* error; invalid processor */
820 }
821 
822 /* Return an integral value for the entry type passed from yyparse.  */
823 
824 static e_type
get_type(int yytype)825 get_type (int yytype)
826 {
827   switch (yytype)
828     {
829       /* translate from yacc's type to enum */
830     case INSN:
831       return e_insn;
832     case DREG:
833       return e_dreg;
834     case CREG:
835       return e_creg;
836     case GREG:
837       return e_greg;
838     case ADDR:
839       return e_addr;
840     case IMMED:
841       return e_immed;
842     default:
843       return e_invtype;		/* error; invalid type */
844     }
845 }
846 
847 /* Allocate and initialize an entry */
848 
849 static struct itbl_entry *
alloc_entry(e_processor processor,e_type type,char * name,unsigned long value)850 alloc_entry (e_processor processor, e_type type,
851 	     char *name, unsigned long value)
852 {
853   struct itbl_entry *e, **es;
854   if (!name)
855     return 0;
856   e = (struct itbl_entry *) malloc (sizeof (struct itbl_entry));
857   if (e)
858     {
859       memset (e, 0, sizeof (struct itbl_entry));
860       e->name = (char *) malloc (sizeof (strlen (name)) + 1);
861       if (e->name)
862 	strcpy (e->name, name);
863       e->processor = processor;
864       e->type = type;
865       e->value = value;
866       es = get_entries (e->processor, e->type);
867       e->next = *es;
868       *es = e;
869     }
870   return e;
871 }
872 
873 /* Allocate and initialize an entry's field */
874 
875 static struct itbl_field *
alloc_field(e_type type,int sbit,int ebit,unsigned long flags)876 alloc_field (e_type type, int sbit, int ebit,
877 	     unsigned long flags)
878 {
879   struct itbl_field *f;
880   f = (struct itbl_field *) malloc (sizeof (struct itbl_field));
881   if (f)
882     {
883       memset (f, 0, sizeof (struct itbl_field));
884       f->type = type;
885       f->range.sbit = sbit;
886       f->range.ebit = ebit;
887       f->flags = flags;
888     }
889   return f;
890 }
891