1/* Assembler interface for targets using CGEN. -*- C -*-
2   CGEN: Cpu tools GENerator
3
4   THIS FILE IS MACHINE GENERATED WITH CGEN.
5   - the resultant file is machine generated, cgen-asm.in isn't
6
7   Copyright (C) 1996-2016 Free Software Foundation, Inc.
8
9   This file is part of libopcodes.
10
11   This library is free software; you can redistribute it and/or modify
12   it under the terms of the GNU General Public License as published by
13   the Free Software Foundation; either version 3, or (at your option)
14   any later version.
15
16   It is distributed in the hope that it will be useful, but WITHOUT
17   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
18   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
19   License for more details.
20
21   You should have received a copy of the GNU General Public License
22   along with this program; if not, write to the Free Software Foundation, Inc.,
23   51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
24
25
26/* ??? Eventually more and more of this stuff can go to cpu-independent files.
27   Keep that in mind.  */
28
29#include "sysdep.h"
30#include <stdio.h>
31#include "ansidecl.h"
32#include "bfd.h"
33#include "symcat.h"
34#include "@prefix@-desc.h"
35#include "@prefix@-opc.h"
36#include "opintl.h"
37#include "xregex.h"
38#include "libiberty.h"
39#include "safe-ctype.h"
40
41#undef  min
42#define min(a,b) ((a) < (b) ? (a) : (b))
43#undef  max
44#define max(a,b) ((a) > (b) ? (a) : (b))
45
46static const char * parse_insn_normal
47  (CGEN_CPU_DESC, const CGEN_INSN *, const char **, CGEN_FIELDS *);
48
49/* -- assembler routines inserted here.  */
50
51
52/* Regex construction routine.
53
54   This translates an opcode syntax string into a regex string,
55   by replacing any non-character syntax element (such as an
56   opcode) with the pattern '.*'
57
58   It then compiles the regex and stores it in the opcode, for
59   later use by @arch@_cgen_assemble_insn
60
61   Returns NULL for success, an error message for failure.  */
62
63char *
64@arch@_cgen_build_insn_regex (CGEN_INSN *insn)
65{
66  CGEN_OPCODE *opc = (CGEN_OPCODE *) CGEN_INSN_OPCODE (insn);
67  const char *mnem = CGEN_INSN_MNEMONIC (insn);
68  char rxbuf[CGEN_MAX_RX_ELEMENTS];
69  char *rx = rxbuf;
70  const CGEN_SYNTAX_CHAR_TYPE *syn;
71  int reg_err;
72
73  syn = CGEN_SYNTAX_STRING (CGEN_OPCODE_SYNTAX (opc));
74
75  /* Mnemonics come first in the syntax string.  */
76  if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
77    return _("missing mnemonic in syntax string");
78  ++syn;
79
80  /* Generate a case sensitive regular expression that emulates case
81     insensitive matching in the "C" locale.  We cannot generate a case
82     insensitive regular expression because in Turkish locales, 'i' and 'I'
83     are not equal modulo case conversion.  */
84
85  /* Copy the literal mnemonic out of the insn.  */
86  for (; *mnem; mnem++)
87    {
88      char c = *mnem;
89
90      if (ISALPHA (c))
91	{
92	  *rx++ = '[';
93	  *rx++ = TOLOWER (c);
94	  *rx++ = TOUPPER (c);
95	  *rx++ = ']';
96	}
97      else
98	*rx++ = c;
99    }
100
101  /* Copy any remaining literals from the syntax string into the rx.  */
102  for(; * syn != 0 && rx <= rxbuf + (CGEN_MAX_RX_ELEMENTS - 7 - 4); ++syn)
103    {
104      if (CGEN_SYNTAX_CHAR_P (* syn))
105	{
106	  char c = CGEN_SYNTAX_CHAR (* syn);
107
108	  switch (c)
109	    {
110	      /* Escape any regex metacharacters in the syntax.  */
111	    case '.': case '[': case '\\':
112	    case '*': case '^': case '$':
113
114#ifdef CGEN_ESCAPE_EXTENDED_REGEX
115	    case '?': case '{': case '}':
116	    case '(': case ')': case '*':
117	    case '|': case '+': case ']':
118#endif
119	      *rx++ = '\\';
120	      *rx++ = c;
121	      break;
122
123	    default:
124	      if (ISALPHA (c))
125		{
126		  *rx++ = '[';
127		  *rx++ = TOLOWER (c);
128		  *rx++ = TOUPPER (c);
129		  *rx++ = ']';
130		}
131	      else
132		*rx++ = c;
133	      break;
134	    }
135	}
136      else
137	{
138	  /* Replace non-syntax fields with globs.  */
139	  *rx++ = '.';
140	  *rx++ = '*';
141	}
142    }
143
144  /* Trailing whitespace ok.  */
145  * rx++ = '[';
146  * rx++ = ' ';
147  * rx++ = '\t';
148  * rx++ = ']';
149  * rx++ = '*';
150
151  /* But anchor it after that.  */
152  * rx++ = '$';
153  * rx = '\0';
154
155  CGEN_INSN_RX (insn) = xmalloc (sizeof (regex_t));
156  reg_err = regcomp ((regex_t *) CGEN_INSN_RX (insn), rxbuf, REG_NOSUB);
157
158  if (reg_err == 0)
159    return NULL;
160  else
161    {
162      static char msg[80];
163
164      regerror (reg_err, (regex_t *) CGEN_INSN_RX (insn), msg, 80);
165      regfree ((regex_t *) CGEN_INSN_RX (insn));
166      free (CGEN_INSN_RX (insn));
167      (CGEN_INSN_RX (insn)) = NULL;
168      return msg;
169    }
170}
171
172
173/* Default insn parser.
174
175   The syntax string is scanned and operands are parsed and stored in FIELDS.
176   Relocs are queued as we go via other callbacks.
177
178   ??? Note that this is currently an all-or-nothing parser.  If we fail to
179   parse the instruction, we return 0 and the caller will start over from
180   the beginning.  Backtracking will be necessary in parsing subexpressions,
181   but that can be handled there.  Not handling backtracking here may get
182   expensive in the case of the m68k.  Deal with later.
183
184   Returns NULL for success, an error message for failure.  */
185
186static const char *
187parse_insn_normal (CGEN_CPU_DESC cd,
188		   const CGEN_INSN *insn,
189		   const char **strp,
190		   CGEN_FIELDS *fields)
191{
192  /* ??? Runtime added insns not handled yet.  */
193  const CGEN_SYNTAX *syntax = CGEN_INSN_SYNTAX (insn);
194  const char *str = *strp;
195  const char *errmsg;
196  const char *p;
197  const CGEN_SYNTAX_CHAR_TYPE * syn;
198#ifdef CGEN_MNEMONIC_OPERANDS
199  /* FIXME: wip */
200  int past_opcode_p;
201#endif
202
203  /* For now we assume the mnemonic is first (there are no leading operands).
204     We can parse it without needing to set up operand parsing.
205     GAS's input scrubber will ensure mnemonics are lowercase, but we may
206     not be called from GAS.  */
207  p = CGEN_INSN_MNEMONIC (insn);
208  while (*p && TOLOWER (*p) == TOLOWER (*str))
209    ++p, ++str;
210
211  if (* p)
212    return _("unrecognized instruction");
213
214#ifndef CGEN_MNEMONIC_OPERANDS
215  if (* str && ! ISSPACE (* str))
216    return _("unrecognized instruction");
217#endif
218
219  CGEN_INIT_PARSE (cd);
220  cgen_init_parse_operand (cd);
221#ifdef CGEN_MNEMONIC_OPERANDS
222  past_opcode_p = 0;
223#endif
224
225  /* We don't check for (*str != '\0') here because we want to parse
226     any trailing fake arguments in the syntax string.  */
227  syn = CGEN_SYNTAX_STRING (syntax);
228
229  /* Mnemonics come first for now, ensure valid string.  */
230  if (! CGEN_SYNTAX_MNEMONIC_P (* syn))
231    abort ();
232
233  ++syn;
234
235  while (* syn != 0)
236    {
237      /* Non operand chars must match exactly.  */
238      if (CGEN_SYNTAX_CHAR_P (* syn))
239	{
240	  /* FIXME: While we allow for non-GAS callers above, we assume the
241	     first char after the mnemonic part is a space.  */
242	  /* FIXME: We also take inappropriate advantage of the fact that
243	     GAS's input scrubber will remove extraneous blanks.  */
244	  if (TOLOWER (*str) == TOLOWER (CGEN_SYNTAX_CHAR (* syn)))
245	    {
246#ifdef CGEN_MNEMONIC_OPERANDS
247	      if (CGEN_SYNTAX_CHAR(* syn) == ' ')
248		past_opcode_p = 1;
249#endif
250	      ++ syn;
251	      ++ str;
252	    }
253	  else if (*str)
254	    {
255	      /* Syntax char didn't match.  Can't be this insn.  */
256	      static char msg [80];
257
258	      /* xgettext:c-format */
259	      sprintf (msg, _("syntax error (expected char `%c', found `%c')"),
260		       CGEN_SYNTAX_CHAR(*syn), *str);
261	      return msg;
262	    }
263	  else
264	    {
265	      /* Ran out of input.  */
266	      static char msg [80];
267
268	      /* xgettext:c-format */
269	      sprintf (msg, _("syntax error (expected char `%c', found end of instruction)"),
270		       CGEN_SYNTAX_CHAR(*syn));
271	      return msg;
272	    }
273	  continue;
274	}
275
276#ifdef CGEN_MNEMONIC_OPERANDS
277      (void) past_opcode_p;
278#endif
279      /* We have an operand of some sort.  */
280      errmsg = cd->parse_operand (cd, CGEN_SYNTAX_FIELD (*syn), &str, fields);
281      if (errmsg)
282	return errmsg;
283
284      /* Done with this operand, continue with next one.  */
285      ++ syn;
286    }
287
288  /* If we're at the end of the syntax string, we're done.  */
289  if (* syn == 0)
290    {
291      /* FIXME: For the moment we assume a valid `str' can only contain
292	 blanks now.  IE: We needn't try again with a longer version of
293	 the insn and it is assumed that longer versions of insns appear
294	 before shorter ones (eg: lsr r2,r3,1 vs lsr r2,r3).  */
295      while (ISSPACE (* str))
296	++ str;
297
298      if (* str != '\0')
299	return _("junk at end of line"); /* FIXME: would like to include `str' */
300
301      return NULL;
302    }
303
304  /* We couldn't parse it.  */
305  return _("unrecognized instruction");
306}
307
308/* Main entry point.
309   This routine is called for each instruction to be assembled.
310   STR points to the insn to be assembled.
311   We assume all necessary tables have been initialized.
312   The assembled instruction, less any fixups, is stored in BUF.
313   Remember that if CGEN_INT_INSN_P then BUF is an int and thus the value
314   still needs to be converted to target byte order, otherwise BUF is an array
315   of bytes in target byte order.
316   The result is a pointer to the insn's entry in the opcode table,
317   or NULL if an error occured (an error message will have already been
318   printed).
319
320   Note that when processing (non-alias) macro-insns,
321   this function recurses.
322
323   ??? It's possible to make this cpu-independent.
324   One would have to deal with a few minor things.
325   At this point in time doing so would be more of a curiosity than useful
326   [for example this file isn't _that_ big], but keeping the possibility in
327   mind helps keep the design clean.  */
328
329const CGEN_INSN *
330@arch@_cgen_assemble_insn (CGEN_CPU_DESC cd,
331			   const char *str,
332			   CGEN_FIELDS *fields,
333			   CGEN_INSN_BYTES_PTR buf,
334			   char **errmsg)
335{
336  const char *start;
337  CGEN_INSN_LIST *ilist;
338  const char *parse_errmsg = NULL;
339  const char *insert_errmsg = NULL;
340  int recognized_mnemonic = 0;
341
342  /* Skip leading white space.  */
343  while (ISSPACE (* str))
344    ++ str;
345
346  /* The instructions are stored in hashed lists.
347     Get the first in the list.  */
348  ilist = CGEN_ASM_LOOKUP_INSN (cd, str);
349
350  /* Keep looking until we find a match.  */
351  start = str;
352  for ( ; ilist != NULL ; ilist = CGEN_ASM_NEXT_INSN (ilist))
353    {
354      const CGEN_INSN *insn = ilist->insn;
355      recognized_mnemonic = 1;
356
357#ifdef CGEN_VALIDATE_INSN_SUPPORTED
358      /* Not usually needed as unsupported opcodes
359	 shouldn't be in the hash lists.  */
360      /* Is this insn supported by the selected cpu?  */
361      if (! @arch@_cgen_insn_supported (cd, insn))
362	continue;
363#endif
364      /* If the RELAXED attribute is set, this is an insn that shouldn't be
365	 chosen immediately.  Instead, it is used during assembler/linker
366	 relaxation if possible.  */
367      if (CGEN_INSN_ATTR_VALUE (insn, CGEN_INSN_RELAXED) != 0)
368	continue;
369
370      str = start;
371
372      /* Skip this insn if str doesn't look right lexically.  */
373      if (CGEN_INSN_RX (insn) != NULL &&
374	  regexec ((regex_t *) CGEN_INSN_RX (insn), str, 0, NULL, 0) == REG_NOMATCH)
375	continue;
376
377      /* Allow parse/insert handlers to obtain length of insn.  */
378      CGEN_FIELDS_BITSIZE (fields) = CGEN_INSN_BITSIZE (insn);
379
380      parse_errmsg = CGEN_PARSE_FN (cd, insn) (cd, insn, & str, fields);
381      if (parse_errmsg != NULL)
382	continue;
383
384      /* ??? 0 is passed for `pc'.  */
385      insert_errmsg = CGEN_INSERT_FN (cd, insn) (cd, insn, fields, buf,
386						 (bfd_vma) 0);
387      if (insert_errmsg != NULL)
388        continue;
389
390      /* It is up to the caller to actually output the insn and any
391         queued relocs.  */
392      return insn;
393    }
394
395  {
396    static char errbuf[150];
397    const char *tmp_errmsg;
398#ifdef CGEN_VERBOSE_ASSEMBLER_ERRORS
399#define be_verbose 1
400#else
401#define be_verbose 0
402#endif
403
404    if (be_verbose)
405      {
406	/* If requesting verbose error messages, use insert_errmsg.
407	   Failing that, use parse_errmsg.  */
408	tmp_errmsg = (insert_errmsg ? insert_errmsg :
409		      parse_errmsg ? parse_errmsg :
410		      recognized_mnemonic ?
411		      _("unrecognized form of instruction") :
412		      _("unrecognized instruction"));
413
414	if (strlen (start) > 50)
415	  /* xgettext:c-format */
416	  sprintf (errbuf, "%s `%.50s...'", tmp_errmsg, start);
417	else
418	  /* xgettext:c-format */
419	  sprintf (errbuf, "%s `%.50s'", tmp_errmsg, start);
420      }
421    else
422      {
423	if (strlen (start) > 50)
424	  /* xgettext:c-format */
425	  sprintf (errbuf, _("bad instruction `%.50s...'"), start);
426	else
427	  /* xgettext:c-format */
428	  sprintf (errbuf, _("bad instruction `%.50s'"), start);
429      }
430
431    *errmsg = errbuf;
432    return NULL;
433  }
434}
435