xref: /openbsd/gnu/usr.bin/binutils-2.17/gas/app.c (revision f6aab3d8)
1 /* This is the Assembler Pre-Processor
2    Copyright 1987, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3    1999, 2000, 2001, 2002, 2003
4    Free Software Foundation, Inc.
5 
6    This file is part of GAS, the GNU Assembler.
7 
8    GAS 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 2, or (at your option)
11    any later version.
12 
13    GAS 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 GAS; see the file COPYING.  If not, write to the Free
20    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
21    02110-1301, USA.  */
22 
23 /* Modified by Allen Wirfs-Brock, Instantiations Inc 2/90.  */
24 /* App, the assembler pre-processor.  This pre-processor strips out excess
25    spaces, turns single-quoted characters into a decimal constant, and turns
26    # <number> <filename> <garbage> into a .line <number>\n.file <filename>
27    pair.  This needs better error-handling.  */
28 
29 #include <stdio.h>
30 #include "as.h"			/* For BAD_CASE() only.  */
31 
32 #if (__STDC__ != 1)
33 #ifndef const
34 #define const  /* empty */
35 #endif
36 #endif
37 
38 #ifdef TC_M68K
39 /* Whether we are scrubbing in m68k MRI mode.  This is different from
40    flag_m68k_mri, because the two flags will be affected by the .mri
41    pseudo-op at different times.  */
42 static int scrub_m68k_mri;
43 
44 /* The pseudo-op which switches in and out of MRI mode.  See the
45    comment in do_scrub_chars.  */
46 static const char mri_pseudo[] = ".mri 0";
47 #else
48 #define scrub_m68k_mri 0
49 #endif
50 
51 #if defined TC_ARM && defined OBJ_ELF
52 /* The pseudo-op for which we need to special-case `@' characters.
53    See the comment in do_scrub_chars.  */
54 static const char   symver_pseudo[] = ".symver";
55 static const char * symver_state;
56 #endif
57 
58 static char lex[256];
59 static const char symbol_chars[] =
60 "$._ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
61 
62 #define LEX_IS_SYMBOL_COMPONENT		1
63 #define LEX_IS_WHITESPACE		2
64 #define LEX_IS_LINE_SEPARATOR		3
65 #define LEX_IS_COMMENT_START		4
66 #define LEX_IS_LINE_COMMENT_START	5
67 #define	LEX_IS_TWOCHAR_COMMENT_1ST	6
68 #define	LEX_IS_STRINGQUOTE		8
69 #define	LEX_IS_COLON			9
70 #define	LEX_IS_NEWLINE			10
71 #define	LEX_IS_ONECHAR_QUOTE		11
72 #ifdef TC_V850
73 #define LEX_IS_DOUBLEDASH_1ST		12
74 #endif
75 #ifdef TC_M32R
76 #define DOUBLEBAR_PARALLEL
77 #endif
78 #ifdef DOUBLEBAR_PARALLEL
79 #define LEX_IS_DOUBLEBAR_1ST		13
80 #endif
81 #define LEX_IS_PARALLEL_SEPARATOR	14
82 #define IS_SYMBOL_COMPONENT(c)		(lex[c] == LEX_IS_SYMBOL_COMPONENT)
83 #define IS_WHITESPACE(c)		(lex[c] == LEX_IS_WHITESPACE)
84 #define IS_LINE_SEPARATOR(c)		(lex[c] == LEX_IS_LINE_SEPARATOR)
85 #define IS_PARALLEL_SEPARATOR(c)	(lex[c] == LEX_IS_PARALLEL_SEPARATOR)
86 #define IS_COMMENT(c)			(lex[c] == LEX_IS_COMMENT_START)
87 #define IS_LINE_COMMENT(c)		(lex[c] == LEX_IS_LINE_COMMENT_START)
88 #define	IS_NEWLINE(c)			(lex[c] == LEX_IS_NEWLINE)
89 
90 static int process_escape (int);
91 
92 /* FIXME-soon: The entire lexer/parser thingy should be
93    built statically at compile time rather than dynamically
94    each and every time the assembler is run.  xoxorich.  */
95 
96 void
97 do_scrub_begin (int m68k_mri ATTRIBUTE_UNUSED)
98 {
99   const char *p;
100   int c;
101 
102   lex[' '] = LEX_IS_WHITESPACE;
103   lex['\t'] = LEX_IS_WHITESPACE;
104   lex['\r'] = LEX_IS_WHITESPACE;
105   lex['\n'] = LEX_IS_NEWLINE;
106   lex[':'] = LEX_IS_COLON;
107 
108 #ifdef TC_M68K
109   scrub_m68k_mri = m68k_mri;
110 
111   if (! m68k_mri)
112 #endif
113     {
114       lex['"'] = LEX_IS_STRINGQUOTE;
115 
116 #if ! defined (TC_HPPA) && ! defined (TC_I370)
117       /* I370 uses single-quotes to delimit integer, float constants.  */
118       lex['\''] = LEX_IS_ONECHAR_QUOTE;
119 #endif
120 
121 #ifdef SINGLE_QUOTE_STRINGS
122       lex['\''] = LEX_IS_STRINGQUOTE;
123 #endif
124     }
125 
126   /* Note: if any other character can be LEX_IS_STRINGQUOTE, the loop
127      in state 5 of do_scrub_chars must be changed.  */
128 
129   /* Note that these override the previous defaults, e.g. if ';' is a
130      comment char, then it isn't a line separator.  */
131   for (p = symbol_chars; *p; ++p)
132     lex[(unsigned char) *p] = LEX_IS_SYMBOL_COMPONENT;
133 
134   for (c = 128; c < 256; ++c)
135     lex[c] = LEX_IS_SYMBOL_COMPONENT;
136 
137 #ifdef tc_symbol_chars
138   /* This macro permits the processor to specify all characters which
139      may appears in an operand.  This will prevent the scrubber from
140      discarding meaningful whitespace in certain cases.  The i386
141      backend uses this to support prefixes, which can confuse the
142      scrubber as to whether it is parsing operands or opcodes.  */
143   for (p = tc_symbol_chars; *p; ++p)
144     lex[(unsigned char) *p] = LEX_IS_SYMBOL_COMPONENT;
145 #endif
146 
147   /* The m68k backend wants to be able to change comment_chars.  */
148 #ifndef tc_comment_chars
149 #define tc_comment_chars comment_chars
150 #endif
151   for (p = tc_comment_chars; *p; p++)
152     lex[(unsigned char) *p] = LEX_IS_COMMENT_START;
153 
154   for (p = line_comment_chars; *p; p++)
155     lex[(unsigned char) *p] = LEX_IS_LINE_COMMENT_START;
156 
157   for (p = line_separator_chars; *p; p++)
158     lex[(unsigned char) *p] = LEX_IS_LINE_SEPARATOR;
159 
160 #ifdef tc_parallel_separator_chars
161   /* This macro permits the processor to specify all characters which
162      separate parallel insns on the same line.  */
163   for (p = tc_parallel_separator_chars; *p; p++)
164     lex[(unsigned char) *p] = LEX_IS_PARALLEL_SEPARATOR;
165 #endif
166 
167   /* Only allow slash-star comments if slash is not in use.
168      FIXME: This isn't right.  We should always permit them.  */
169   if (lex['/'] == 0)
170     lex['/'] = LEX_IS_TWOCHAR_COMMENT_1ST;
171 
172 #ifdef TC_M68K
173   if (m68k_mri)
174     {
175       lex['\''] = LEX_IS_STRINGQUOTE;
176       lex[';'] = LEX_IS_COMMENT_START;
177       lex['*'] = LEX_IS_LINE_COMMENT_START;
178       /* The MRI documentation says '!' is LEX_IS_COMMENT_START, but
179 	 then it can't be used in an expression.  */
180       lex['!'] = LEX_IS_LINE_COMMENT_START;
181     }
182 #endif
183 
184 #ifdef TC_V850
185   lex['-'] = LEX_IS_DOUBLEDASH_1ST;
186 #endif
187 #ifdef DOUBLEBAR_PARALLEL
188   lex['|'] = LEX_IS_DOUBLEBAR_1ST;
189 #endif
190 #ifdef TC_D30V
191   /* Must do this is we want VLIW instruction with "->" or "<-".  */
192   lex['-'] = LEX_IS_SYMBOL_COMPONENT;
193 #endif
194 }
195 
196 /* Saved state of the scrubber.  */
197 static int state;
198 static int old_state;
199 static char *out_string;
200 static char out_buf[20];
201 static int add_newlines;
202 static char *saved_input;
203 static int saved_input_len;
204 static char input_buffer[32 * 1024];
205 static const char *mri_state;
206 static char mri_last_ch;
207 
208 /* Data structure for saving the state of app across #include's.  Note that
209    app is called asynchronously to the parsing of the .include's, so our
210    state at the time .include is interpreted is completely unrelated.
211    That's why we have to save it all.  */
212 
213 struct app_save
214 {
215   int          state;
216   int          old_state;
217   char *       out_string;
218   char         out_buf[sizeof (out_buf)];
219   int          add_newlines;
220   char *       saved_input;
221   int          saved_input_len;
222 #ifdef TC_M68K
223   int          scrub_m68k_mri;
224 #endif
225   const char * mri_state;
226   char         mri_last_ch;
227 #if defined TC_ARM && defined OBJ_ELF
228   const char * symver_state;
229 #endif
230 };
231 
232 char *
233 app_push (void)
234 {
235   register struct app_save *saved;
236 
237   saved = (struct app_save *) xmalloc (sizeof (*saved));
238   saved->state = state;
239   saved->old_state = old_state;
240   saved->out_string = out_string;
241   memcpy (saved->out_buf, out_buf, sizeof (out_buf));
242   saved->add_newlines = add_newlines;
243   if (saved_input == NULL)
244     saved->saved_input = NULL;
245   else
246     {
247       saved->saved_input = xmalloc (saved_input_len);
248       memcpy (saved->saved_input, saved_input, saved_input_len);
249       saved->saved_input_len = saved_input_len;
250     }
251 #ifdef TC_M68K
252   saved->scrub_m68k_mri = scrub_m68k_mri;
253 #endif
254   saved->mri_state = mri_state;
255   saved->mri_last_ch = mri_last_ch;
256 #if defined TC_ARM && defined OBJ_ELF
257   saved->symver_state = symver_state;
258 #endif
259 
260   /* do_scrub_begin() is not useful, just wastes time.  */
261 
262   state = 0;
263   saved_input = NULL;
264 
265   return (char *) saved;
266 }
267 
268 void
269 app_pop (char *arg)
270 {
271   register struct app_save *saved = (struct app_save *) arg;
272 
273   /* There is no do_scrub_end ().  */
274   state = saved->state;
275   old_state = saved->old_state;
276   out_string = saved->out_string;
277   memcpy (out_buf, saved->out_buf, sizeof (out_buf));
278   add_newlines = saved->add_newlines;
279   if (saved->saved_input == NULL)
280     saved_input = NULL;
281   else
282     {
283       assert (saved->saved_input_len <= (int) (sizeof input_buffer));
284       memcpy (input_buffer, saved->saved_input, saved->saved_input_len);
285       saved_input = input_buffer;
286       saved_input_len = saved->saved_input_len;
287       free (saved->saved_input);
288     }
289 #ifdef TC_M68K
290   scrub_m68k_mri = saved->scrub_m68k_mri;
291 #endif
292   mri_state = saved->mri_state;
293   mri_last_ch = saved->mri_last_ch;
294 #if defined TC_ARM && defined OBJ_ELF
295   symver_state = saved->symver_state;
296 #endif
297 
298   free (arg);
299 }
300 
301 /* @@ This assumes that \n &c are the same on host and target.  This is not
302    necessarily true.  */
303 
304 static int
305 process_escape (int ch)
306 {
307   switch (ch)
308     {
309     case 'b':
310       return '\b';
311     case 'f':
312       return '\f';
313     case 'n':
314       return '\n';
315     case 'r':
316       return '\r';
317     case 't':
318       return '\t';
319     case '\'':
320       return '\'';
321     case '"':
322       return '\"';
323     default:
324       return ch;
325     }
326 }
327 
328 /* This function is called to process input characters.  The GET
329    parameter is used to retrieve more input characters.  GET should
330    set its parameter to point to a buffer, and return the length of
331    the buffer; it should return 0 at end of file.  The scrubbed output
332    characters are put into the buffer starting at TOSTART; the TOSTART
333    buffer is TOLEN bytes in length.  The function returns the number
334    of scrubbed characters put into TOSTART.  This will be TOLEN unless
335    end of file was seen.  This function is arranged as a state
336    machine, and saves its state so that it may return at any point.
337    This is the way the old code used to work.  */
338 
339 int
340 do_scrub_chars (int (*get) (char *, int), char *tostart, int tolen)
341 {
342   char *to = tostart;
343   char *toend = tostart + tolen;
344   char *from;
345   char *fromend;
346   int fromlen;
347   register int ch, ch2 = 0;
348   /* Character that started the string we're working on.  */
349   static char quotechar;
350 
351   /*State 0: beginning of normal line
352 	  1: After first whitespace on line (flush more white)
353 	  2: After first non-white (opcode) on line (keep 1white)
354 	  3: after second white on line (into operands) (flush white)
355 	  4: after putting out a .line, put out digits
356 	  5: parsing a string, then go to old-state
357 	  6: putting out \ escape in a "d string.
358 	  7: After putting out a .appfile, put out string.
359 	  8: After putting out a .appfile string, flush until newline.
360 	  9: After seeing symbol char in state 3 (keep 1white after symchar)
361 	 10: After seeing whitespace in state 9 (keep white before symchar)
362 	 11: After seeing a symbol character in state 0 (eg a label definition)
363 	 -1: output string in out_string and go to the state in old_state
364 	 -2: flush text until a '*' '/' is seen, then go to state old_state
365 #ifdef TC_V850
366 	 12: After seeing a dash, looking for a second dash as a start
367 	     of comment.
368 #endif
369 #ifdef DOUBLEBAR_PARALLEL
370 	 13: After seeing a vertical bar, looking for a second
371 	     vertical bar as a parallel expression separator.
372 #endif
373 #ifdef TC_IA64
374 	 14: After seeing a `(' at state 0, looking for a `)' as
375 	     predicate.
376 	 15: After seeing a `(' at state 1, looking for a `)' as
377 	     predicate.
378 #endif
379 #ifdef TC_Z80
380 	 16: After seeing an 'a' or an 'A' at the start of a symbol
381 	 17: After seeing an 'f' or an 'F' in state 16
382 #endif
383 	  */
384 
385   /* I added states 9 and 10 because the MIPS ECOFF assembler uses
386      constructs like ``.loc 1 20''.  This was turning into ``.loc
387      120''.  States 9 and 10 ensure that a space is never dropped in
388      between characters which could appear in an identifier.  Ian
389      Taylor, ian@cygnus.com.
390 
391      I added state 11 so that something like "Lfoo add %r25,%r26,%r27" works
392      correctly on the PA (and any other target where colons are optional).
393      Jeff Law, law@cs.utah.edu.
394 
395      I added state 13 so that something like "cmp r1, r2 || trap #1" does not
396      get squashed into "cmp r1,r2||trap#1", with the all important space
397      between the 'trap' and the '#1' being eliminated.  nickc@cygnus.com  */
398 
399   /* This macro gets the next input character.  */
400 
401 #define GET()							\
402   (from < fromend						\
403    ? * (unsigned char *) (from++)				\
404    : (saved_input = NULL,					\
405       fromlen = (*get) (input_buffer, sizeof input_buffer),	\
406       from = input_buffer,					\
407       fromend = from + fromlen,					\
408       (fromlen == 0						\
409        ? EOF							\
410        : * (unsigned char *) (from++))))
411 
412   /* This macro pushes a character back on the input stream.  */
413 
414 #define UNGET(uch) (*--from = (uch))
415 
416   /* This macro puts a character into the output buffer.  If this
417      character fills the output buffer, this macro jumps to the label
418      TOFULL.  We use this rather ugly approach because we need to
419      handle two different termination conditions: EOF on the input
420      stream, and a full output buffer.  It would be simpler if we
421      always read in the entire input stream before processing it, but
422      I don't want to make such a significant change to the assembler's
423      memory usage.  */
424 
425 #define PUT(pch)				\
426   do						\
427     {						\
428       *to++ = (pch);				\
429       if (to >= toend)				\
430 	goto tofull;				\
431     }						\
432   while (0)
433 
434   if (saved_input != NULL)
435     {
436       from = saved_input;
437       fromend = from + saved_input_len;
438     }
439   else
440     {
441       fromlen = (*get) (input_buffer, sizeof input_buffer);
442       if (fromlen == 0)
443 	return 0;
444       from = input_buffer;
445       fromend = from + fromlen;
446     }
447 
448   while (1)
449     {
450       /* The cases in this switch end with continue, in order to
451 	 branch back to the top of this while loop and generate the
452 	 next output character in the appropriate state.  */
453       switch (state)
454 	{
455 	case -1:
456 	  ch = *out_string++;
457 	  if (*out_string == '\0')
458 	    {
459 	      state = old_state;
460 	      old_state = 3;
461 	    }
462 	  PUT (ch);
463 	  continue;
464 
465 	case -2:
466 	  for (;;)
467 	    {
468 	      do
469 		{
470 		  ch = GET ();
471 
472 		  if (ch == EOF)
473 		    {
474 		      as_warn (_("end of file in comment"));
475 		      goto fromeof;
476 		    }
477 
478 		  if (ch == '\n')
479 		    PUT ('\n');
480 		}
481 	      while (ch != '*');
482 
483 	      while ((ch = GET ()) == '*')
484 		;
485 
486 	      if (ch == EOF)
487 		{
488 		  as_warn (_("end of file in comment"));
489 		  goto fromeof;
490 		}
491 
492 	      if (ch == '/')
493 		break;
494 
495 	      UNGET (ch);
496 	    }
497 
498 	  state = old_state;
499 	  UNGET (' ');
500 	  continue;
501 
502 	case 4:
503 	  ch = GET ();
504 	  if (ch == EOF)
505 	    goto fromeof;
506 	  else if (ch >= '0' && ch <= '9')
507 	    PUT (ch);
508 	  else
509 	    {
510 	      while (ch != EOF && IS_WHITESPACE (ch))
511 		ch = GET ();
512 	      if (ch == '"')
513 		{
514 		  UNGET (ch);
515 		  if (scrub_m68k_mri)
516 		    out_string = "\n\tappfile ";
517 		  else
518 		    out_string = "\n\t.appfile ";
519 		  old_state = 7;
520 		  state = -1;
521 		  PUT (*out_string++);
522 		}
523 	      else
524 		{
525 		  while (ch != EOF && ch != '\n')
526 		    ch = GET ();
527 		  state = 0;
528 		  PUT (ch);
529 		}
530 	    }
531 	  continue;
532 
533 	case 5:
534 	  /* We are going to copy everything up to a quote character,
535 	     with special handling for a backslash.  We try to
536 	     optimize the copying in the simple case without using the
537 	     GET and PUT macros.  */
538 	  {
539 	    char *s;
540 	    int len;
541 
542 	    for (s = from; s < fromend; s++)
543 	      {
544 		ch = *s;
545 		if (ch == '\\'
546 		    || ch == quotechar
547 		    || ch == '\n')
548 		  break;
549 	      }
550 	    len = s - from;
551 	    if (len > toend - to)
552 	      len = toend - to;
553 	    if (len > 0)
554 	      {
555 		memcpy (to, from, len);
556 		to += len;
557 		from += len;
558 	      }
559 	  }
560 
561 	  ch = GET ();
562 	  if (ch == EOF)
563 	    {
564 	      as_warn (_("end of file in string; '%c' inserted"), quotechar);
565 	      state = old_state;
566 	      UNGET ('\n');
567 	      PUT (quotechar);
568 	    }
569 	  else if (ch == quotechar)
570 	    {
571 	      state = old_state;
572 	      PUT (ch);
573 	    }
574 #ifndef NO_STRING_ESCAPES
575 	  else if (ch == '\\')
576 	    {
577 	      state = 6;
578 	      PUT (ch);
579 	    }
580 #endif
581 	  else if (scrub_m68k_mri && ch == '\n')
582 	    {
583 	      /* Just quietly terminate the string.  This permits lines like
584 		   bne	label	loop if we haven't reach end yet.  */
585 	      state = old_state;
586 	      UNGET (ch);
587 	      PUT ('\'');
588 	    }
589 	  else
590 	    {
591 	      PUT (ch);
592 	    }
593 	  continue;
594 
595 	case 6:
596 	  state = 5;
597 	  ch = GET ();
598 	  switch (ch)
599 	    {
600 	      /* Handle strings broken across lines, by turning '\n' into
601 		 '\\' and 'n'.  */
602 	    case '\n':
603 	      UNGET ('n');
604 	      add_newlines++;
605 	      PUT ('\\');
606 	      continue;
607 
608 	    case EOF:
609 	      as_warn (_("end of file in string; '%c' inserted"), quotechar);
610 	      PUT (quotechar);
611 	      continue;
612 
613 	    case '"':
614 	    case '\\':
615 	    case 'b':
616 	    case 'f':
617 	    case 'n':
618 	    case 'r':
619 	    case 't':
620 	    case 'v':
621 	    case 'x':
622 	    case 'X':
623 	    case '0':
624 	    case '1':
625 	    case '2':
626 	    case '3':
627 	    case '4':
628 	    case '5':
629 	    case '6':
630 	    case '7':
631 	      break;
632 
633 	    default:
634 #ifdef ONLY_STANDARD_ESCAPES
635 	      as_warn (_("unknown escape '\\%c' in string; ignored"), ch);
636 #endif
637 	      break;
638 	    }
639 	  PUT (ch);
640 	  continue;
641 
642 	case 7:
643 	  ch = GET ();
644 	  quotechar = ch;
645 	  state = 5;
646 	  old_state = 8;
647 	  PUT (ch);
648 	  continue;
649 
650 	case 8:
651 	  do
652 	    ch = GET ();
653 	  while (ch != '\n' && ch != EOF);
654 	  if (ch == EOF)
655 	    goto fromeof;
656 	  state = 0;
657 	  PUT (ch);
658 	  continue;
659 
660 #ifdef DOUBLEBAR_PARALLEL
661 	case 13:
662 	  ch = GET ();
663 	  if (ch != '|')
664 	    abort ();
665 
666 	  /* Reset back to state 1 and pretend that we are parsing a
667 	     line from just after the first white space.  */
668 	  state = 1;
669 	  PUT ('|');
670 	  continue;
671 #endif
672 #ifdef TC_Z80
673 	case 16:
674 	  /* We have seen an 'a' at the start of a symbol, look for an 'f'.  */
675 	  ch = GET ();
676 	  if (ch == 'f' || ch == 'F')
677 	    {
678 	      state = 17;
679 	      PUT (ch);
680 	    }
681 	  else
682 	    {
683 	      state = 9;
684 	      break;
685 	    }
686 	case 17:
687 	  /* We have seen "af" at the start of a symbol,
688 	     a ' here is a part of that symbol.  */
689 	  ch = GET ();
690 	  state = 9;
691 	  if (ch == '\'')
692 	    /* Change to avoid warning about unclosed string.  */
693 	    PUT ('`');
694 	  else
695 	    UNGET (ch);
696 	  break;
697 #endif
698 	}
699 
700       /* OK, we are somewhere in states 0 through 4 or 9 through 11.  */
701 
702       /* flushchar: */
703       ch = GET ();
704 
705 #ifdef TC_IA64
706       if (ch == '(' && (state == 0 || state == 1))
707 	{
708 	  state += 14;
709 	  PUT (ch);
710 	  continue;
711 	}
712       else if (state == 14 || state == 15)
713 	{
714 	  if (ch == ')')
715 	    {
716 	      state -= 14;
717 	      PUT (ch);
718 	      ch = GET ();
719 	    }
720 	  else
721 	    {
722 	      PUT (ch);
723 	      continue;
724 	    }
725 	}
726 #endif
727 
728     recycle:
729 
730 #if defined TC_ARM && defined OBJ_ELF
731       /* We need to watch out for .symver directives.  See the comment later
732 	 in this function.  */
733       if (symver_state == NULL)
734 	{
735 	  if ((state == 0 || state == 1) && ch == symver_pseudo[0])
736 	    symver_state = symver_pseudo + 1;
737 	}
738       else
739 	{
740 	  /* We advance to the next state if we find the right
741 	     character.  */
742 	  if (ch != '\0' && (*symver_state == ch))
743 	    ++symver_state;
744 	  else if (*symver_state != '\0')
745 	    /* We did not get the expected character, or we didn't
746 	       get a valid terminating character after seeing the
747 	       entire pseudo-op, so we must go back to the beginning.  */
748 	    symver_state = NULL;
749 	  else
750 	    {
751 	      /* We've read the entire pseudo-op.  If this is the end
752 		 of the line, go back to the beginning.  */
753 	      if (IS_NEWLINE (ch))
754 		symver_state = NULL;
755 	    }
756 	}
757 #endif /* TC_ARM && OBJ_ELF */
758 
759 #ifdef TC_M68K
760       /* We want to have pseudo-ops which control whether we are in
761 	 MRI mode or not.  Unfortunately, since m68k MRI mode affects
762 	 the scrubber, that means that we need a special purpose
763 	 recognizer here.  */
764       if (mri_state == NULL)
765 	{
766 	  if ((state == 0 || state == 1)
767 	      && ch == mri_pseudo[0])
768 	    mri_state = mri_pseudo + 1;
769 	}
770       else
771 	{
772 	  /* We advance to the next state if we find the right
773 	     character, or if we need a space character and we get any
774 	     whitespace character, or if we need a '0' and we get a
775 	     '1' (this is so that we only need one state to handle
776 	     ``.mri 0'' and ``.mri 1'').  */
777 	  if (ch != '\0'
778 	      && (*mri_state == ch
779 		  || (*mri_state == ' '
780 		      && lex[ch] == LEX_IS_WHITESPACE)
781 		  || (*mri_state == '0'
782 		      && ch == '1')))
783 	    {
784 	      mri_last_ch = ch;
785 	      ++mri_state;
786 	    }
787 	  else if (*mri_state != '\0'
788 		   || (lex[ch] != LEX_IS_WHITESPACE
789 		       && lex[ch] != LEX_IS_NEWLINE))
790 	    {
791 	      /* We did not get the expected character, or we didn't
792 		 get a valid terminating character after seeing the
793 		 entire pseudo-op, so we must go back to the
794 		 beginning.  */
795 	      mri_state = NULL;
796 	    }
797 	  else
798 	    {
799 	      /* We've read the entire pseudo-op.  mips_last_ch is
800 		 either '0' or '1' indicating whether to enter or
801 		 leave MRI mode.  */
802 	      do_scrub_begin (mri_last_ch == '1');
803 	      mri_state = NULL;
804 
805 	      /* We continue handling the character as usual.  The
806 		 main gas reader must also handle the .mri pseudo-op
807 		 to control expression parsing and the like.  */
808 	    }
809 	}
810 #endif
811 
812       if (ch == EOF)
813 	{
814 	  if (state != 0)
815 	    {
816 	      as_warn (_("end of file not at end of a line; newline inserted"));
817 	      state = 0;
818 	      PUT ('\n');
819 	    }
820 	  goto fromeof;
821 	}
822 
823       switch (lex[ch])
824 	{
825 	case LEX_IS_WHITESPACE:
826 	  do
827 	    {
828 	      ch = GET ();
829 	    }
830 	  while (ch != EOF && IS_WHITESPACE (ch));
831 	  if (ch == EOF)
832 	    goto fromeof;
833 
834 	  if (state == 0)
835 	    {
836 	      /* Preserve a single whitespace character at the
837 		 beginning of a line.  */
838 	      state = 1;
839 	      UNGET (ch);
840 	      PUT (' ');
841 	      break;
842 	    }
843 
844 #ifdef KEEP_WHITE_AROUND_COLON
845 	  if (lex[ch] == LEX_IS_COLON)
846 	    {
847 	      /* Only keep this white if there's no white *after* the
848 		 colon.  */
849 	      ch2 = GET ();
850 	      UNGET (ch2);
851 	      if (!IS_WHITESPACE (ch2))
852 		{
853 		  state = 9;
854 		  UNGET (ch);
855 		  PUT (' ');
856 		  break;
857 		}
858 	    }
859 #endif
860 	  if (IS_COMMENT (ch)
861 	      || ch == '/'
862 	      || IS_LINE_SEPARATOR (ch)
863 	      || IS_PARALLEL_SEPARATOR (ch))
864 	    {
865 	      if (scrub_m68k_mri)
866 		{
867 		  /* In MRI mode, we keep these spaces.  */
868 		  UNGET (ch);
869 		  PUT (' ');
870 		  break;
871 		}
872 	      goto recycle;
873 	    }
874 
875 	  /* If we're in state 2 or 11, we've seen a non-white
876 	     character followed by whitespace.  If the next character
877 	     is ':', this is whitespace after a label name which we
878 	     normally must ignore.  In MRI mode, though, spaces are
879 	     not permitted between the label and the colon.  */
880 	  if ((state == 2 || state == 11)
881 	      && lex[ch] == LEX_IS_COLON
882 	      && ! scrub_m68k_mri)
883 	    {
884 	      state = 1;
885 	      PUT (ch);
886 	      break;
887 	    }
888 
889 	  switch (state)
890 	    {
891 	    case 0:
892 	      state++;
893 	      goto recycle;	/* Punted leading sp */
894 	    case 1:
895 	      /* We can arrive here if we leave a leading whitespace
896 		 character at the beginning of a line.  */
897 	      goto recycle;
898 	    case 2:
899 	      state = 3;
900 	      if (to + 1 < toend)
901 		{
902 		  /* Optimize common case by skipping UNGET/GET.  */
903 		  PUT (' ');	/* Sp after opco */
904 		  goto recycle;
905 		}
906 	      UNGET (ch);
907 	      PUT (' ');
908 	      break;
909 	    case 3:
910 	      if (scrub_m68k_mri)
911 		{
912 		  /* In MRI mode, we keep these spaces.  */
913 		  UNGET (ch);
914 		  PUT (' ');
915 		  break;
916 		}
917 	      goto recycle;	/* Sp in operands */
918 	    case 9:
919 	    case 10:
920 	      if (scrub_m68k_mri)
921 		{
922 		  /* In MRI mode, we keep these spaces.  */
923 		  state = 3;
924 		  UNGET (ch);
925 		  PUT (' ');
926 		  break;
927 		}
928 	      state = 10;	/* Sp after symbol char */
929 	      goto recycle;
930 	    case 11:
931 	      if (LABELS_WITHOUT_COLONS || flag_m68k_mri)
932 		state = 1;
933 	      else
934 		{
935 		  /* We know that ch is not ':', since we tested that
936 		     case above.  Therefore this is not a label, so it
937 		     must be the opcode, and we've just seen the
938 		     whitespace after it.  */
939 		  state = 3;
940 		}
941 	      UNGET (ch);
942 	      PUT (' ');	/* Sp after label definition.  */
943 	      break;
944 	    default:
945 	      BAD_CASE (state);
946 	    }
947 	  break;
948 
949 	case LEX_IS_TWOCHAR_COMMENT_1ST:
950 	  ch2 = GET ();
951 	  if (ch2 == '*')
952 	    {
953 	      for (;;)
954 		{
955 		  do
956 		    {
957 		      ch2 = GET ();
958 		      if (ch2 != EOF && IS_NEWLINE (ch2))
959 			add_newlines++;
960 		    }
961 		  while (ch2 != EOF && ch2 != '*');
962 
963 		  while (ch2 == '*')
964 		    ch2 = GET ();
965 
966 		  if (ch2 == EOF || ch2 == '/')
967 		    break;
968 
969 		  /* This UNGET will ensure that we count newlines
970 		     correctly.  */
971 		  UNGET (ch2);
972 		}
973 
974 	      if (ch2 == EOF)
975 		as_warn (_("end of file in multiline comment"));
976 
977 	      ch = ' ';
978 	      goto recycle;
979 	    }
980 #ifdef DOUBLESLASH_LINE_COMMENTS
981 	  else if (ch2 == '/')
982 	    {
983 	      do
984 		{
985 		  ch = GET ();
986 		}
987 	      while (ch != EOF && !IS_NEWLINE (ch));
988 	      if (ch == EOF)
989 		as_warn ("end of file in comment; newline inserted");
990 	      state = 0;
991 	      PUT ('\n');
992 	      break;
993 	    }
994 #endif
995 	  else
996 	    {
997 	      if (ch2 != EOF)
998 		UNGET (ch2);
999 	      if (state == 9 || state == 10)
1000 		state = 3;
1001 	      PUT (ch);
1002 	    }
1003 	  break;
1004 
1005 	case LEX_IS_STRINGQUOTE:
1006 	  quotechar = ch;
1007 	  if (state == 10)
1008 	    {
1009 	      /* Preserve the whitespace in foo "bar".  */
1010 	      UNGET (ch);
1011 	      state = 3;
1012 	      PUT (' ');
1013 
1014 	      /* PUT didn't jump out.  We could just break, but we
1015 		 know what will happen, so optimize a bit.  */
1016 	      ch = GET ();
1017 	      old_state = 3;
1018 	    }
1019 	  else if (state == 9)
1020 	    old_state = 3;
1021 	  else
1022 	    old_state = state;
1023 	  state = 5;
1024 	  PUT (ch);
1025 	  break;
1026 
1027 #ifndef IEEE_STYLE
1028 	case LEX_IS_ONECHAR_QUOTE:
1029 	  if (state == 10)
1030 	    {
1031 	      /* Preserve the whitespace in foo 'b'.  */
1032 	      UNGET (ch);
1033 	      state = 3;
1034 	      PUT (' ');
1035 	      break;
1036 	    }
1037 	  ch = GET ();
1038 	  if (ch == EOF)
1039 	    {
1040 	      as_warn (_("end of file after a one-character quote; \\0 inserted"));
1041 	      ch = 0;
1042 	    }
1043 	  if (ch == '\\')
1044 	    {
1045 	      ch = GET ();
1046 	      if (ch == EOF)
1047 		{
1048 		  as_warn (_("end of file in escape character"));
1049 		  ch = '\\';
1050 		}
1051 	      else
1052 		ch = process_escape (ch);
1053 	    }
1054 	  sprintf (out_buf, "%d", (int) (unsigned char) ch);
1055 
1056 	  /* None of these 'x constants for us.  We want 'x'.  */
1057 	  if ((ch = GET ()) != '\'')
1058 	    {
1059 #ifdef REQUIRE_CHAR_CLOSE_QUOTE
1060 	      as_warn (_("missing close quote; (assumed)"));
1061 #else
1062 	      if (ch != EOF)
1063 		UNGET (ch);
1064 #endif
1065 	    }
1066 	  if (strlen (out_buf) == 1)
1067 	    {
1068 	      PUT (out_buf[0]);
1069 	      break;
1070 	    }
1071 	  if (state == 9)
1072 	    old_state = 3;
1073 	  else
1074 	    old_state = state;
1075 	  state = -1;
1076 	  out_string = out_buf;
1077 	  PUT (*out_string++);
1078 	  break;
1079 #endif
1080 
1081 	case LEX_IS_COLON:
1082 #ifdef KEEP_WHITE_AROUND_COLON
1083 	  state = 9;
1084 #else
1085 	  if (state == 9 || state == 10)
1086 	    state = 3;
1087 	  else if (state != 3)
1088 	    state = 1;
1089 #endif
1090 	  PUT (ch);
1091 	  break;
1092 
1093 	case LEX_IS_NEWLINE:
1094 	  /* Roll out a bunch of newlines from inside comments, etc.  */
1095 	  if (add_newlines)
1096 	    {
1097 	      --add_newlines;
1098 	      UNGET (ch);
1099 	    }
1100 	  /* Fall through.  */
1101 
1102 	case LEX_IS_LINE_SEPARATOR:
1103 	  state = 0;
1104 	  PUT (ch);
1105 	  break;
1106 
1107 	case LEX_IS_PARALLEL_SEPARATOR:
1108 	  state = 1;
1109 	  PUT (ch);
1110 	  break;
1111 
1112 #ifdef TC_V850
1113 	case LEX_IS_DOUBLEDASH_1ST:
1114 	  ch2 = GET ();
1115 	  if (ch2 != '-')
1116 	    {
1117 	      UNGET (ch2);
1118 	      goto de_fault;
1119 	    }
1120 	  /* Read and skip to end of line.  */
1121 	  do
1122 	    {
1123 	      ch = GET ();
1124 	    }
1125 	  while (ch != EOF && ch != '\n');
1126 
1127 	  if (ch == EOF)
1128 	    as_warn (_("end of file in comment; newline inserted"));
1129 
1130 	  state = 0;
1131 	  PUT ('\n');
1132 	  break;
1133 #endif
1134 #ifdef DOUBLEBAR_PARALLEL
1135 	case LEX_IS_DOUBLEBAR_1ST:
1136 	  ch2 = GET ();
1137 	  UNGET (ch2);
1138 	  if (ch2 != '|')
1139 	    goto de_fault;
1140 
1141 	  /* Handle '||' in two states as invoking PUT twice might
1142 	     result in the first one jumping out of this loop.  We'd
1143 	     then lose track of the state and one '|' char.  */
1144 	  state = 13;
1145 	  PUT ('|');
1146 	  break;
1147 #endif
1148 	case LEX_IS_LINE_COMMENT_START:
1149 	  /* FIXME-someday: The two character comment stuff was badly
1150 	     thought out.  On i386, we want '/' as line comment start
1151 	     AND we want C style comments.  hence this hack.  The
1152 	     whole lexical process should be reworked.  xoxorich.  */
1153 	  if (ch == '/')
1154 	    {
1155 	      ch2 = GET ();
1156 	      if (ch2 == '*')
1157 		{
1158 		  old_state = 3;
1159 		  state = -2;
1160 		  break;
1161 		}
1162 	      else
1163 		{
1164 		  UNGET (ch2);
1165 		}
1166 	    }
1167 
1168 	  if (state == 0 || state == 1)	/* Only comment at start of line.  */
1169 	    {
1170 	      int startch;
1171 
1172 	      startch = ch;
1173 
1174 	      do
1175 		{
1176 		  ch = GET ();
1177 		}
1178 	      while (ch != EOF && IS_WHITESPACE (ch));
1179 
1180 	      if (ch == EOF)
1181 		{
1182 		  as_warn (_("end of file in comment; newline inserted"));
1183 		  PUT ('\n');
1184 		  break;
1185 		}
1186 
1187 	      if (ch < '0' || ch > '9' || state != 0 || startch != '#')
1188 		{
1189 		  /* Not a cpp line.  */
1190 		  while (ch != EOF && !IS_NEWLINE (ch))
1191 		    ch = GET ();
1192 		  if (ch == EOF)
1193 		    as_warn (_("end of file in comment; newline inserted"));
1194 		  state = 0;
1195 		  PUT ('\n');
1196 		  break;
1197 		}
1198 	      /* Looks like `# 123 "filename"' from cpp.  */
1199 	      UNGET (ch);
1200 	      old_state = 4;
1201 	      state = -1;
1202 	      if (scrub_m68k_mri)
1203 		out_string = "\tappline ";
1204 	      else
1205 		out_string = "\t.appline ";
1206 	      PUT (*out_string++);
1207 	      break;
1208 	    }
1209 
1210 #ifdef TC_D10V
1211 	  /* All insns end in a char for which LEX_IS_SYMBOL_COMPONENT is true.
1212 	     Trap is the only short insn that has a first operand that is
1213 	     neither register nor label.
1214 	     We must prevent exef0f ||trap #1 to degenerate to exef0f ||trap#1 .
1215 	     We can't make '#' LEX_IS_SYMBOL_COMPONENT because it is
1216 	     already LEX_IS_LINE_COMMENT_START.  However, it is the
1217 	     only character in line_comment_chars for d10v, hence we
1218 	     can recognize it as such.  */
1219 	  /* An alternative approach would be to reset the state to 1 when
1220 	     we see '||', '<'- or '->', but that seems to be overkill.  */
1221 	  if (state == 10)
1222 	    PUT (' ');
1223 #endif
1224 	  /* We have a line comment character which is not at the
1225 	     start of a line.  If this is also a normal comment
1226 	     character, fall through.  Otherwise treat it as a default
1227 	     character.  */
1228 	  if (strchr (tc_comment_chars, ch) == NULL
1229 	      && (! scrub_m68k_mri
1230 		  || (ch != '!' && ch != '*')))
1231 	    goto de_fault;
1232 	  if (scrub_m68k_mri
1233 	      && (ch == '!' || ch == '*' || ch == '#')
1234 	      && state != 1
1235 	      && state != 10)
1236 	    goto de_fault;
1237 	  /* Fall through.  */
1238 	case LEX_IS_COMMENT_START:
1239 #if defined TC_ARM && defined OBJ_ELF
1240 	  /* On the ARM, `@' is the comment character.
1241 	     Unfortunately this is also a special character in ELF .symver
1242 	     directives (and .type, though we deal with those another way).
1243 	     So we check if this line is such a directive, and treat
1244 	     the character as default if so.  This is a hack.  */
1245 	  if ((symver_state != NULL) && (*symver_state == 0))
1246 	    goto de_fault;
1247 #endif
1248 #ifdef WARN_COMMENTS
1249 	  if (!found_comment)
1250 	    as_where (&found_comment_file, &found_comment);
1251 #endif
1252 	  do
1253 	    {
1254 	      ch = GET ();
1255 	    }
1256 	  while (ch != EOF && !IS_NEWLINE (ch));
1257 	  if (ch == EOF)
1258 	    as_warn (_("end of file in comment; newline inserted"));
1259 	  state = 0;
1260 	  PUT ('\n');
1261 	  break;
1262 
1263 	case LEX_IS_SYMBOL_COMPONENT:
1264 	  if (state == 10)
1265 	    {
1266 	      /* This is a symbol character following another symbol
1267 		 character, with whitespace in between.  We skipped
1268 		 the whitespace earlier, so output it now.  */
1269 	      UNGET (ch);
1270 	      state = 3;
1271 	      PUT (' ');
1272 	      break;
1273 	    }
1274 
1275 #ifdef TC_Z80
1276 	  /* "af'" is a symbol containing '\''.  */
1277 	  if (state == 3 && (ch == 'a' || ch == 'A'))
1278 	    {
1279 	      state = 16;
1280 	      PUT (ch);
1281 	      ch = GET ();
1282 	      if (ch == 'f' || ch == 'F')
1283 		{
1284 		  state = 17;
1285 		  PUT (ch);
1286 		  break;
1287 		}
1288 	      else
1289 		{
1290 		  state = 9;
1291 		  if (!IS_SYMBOL_COMPONENT (ch))
1292 		    {
1293 		      UNGET (ch);
1294 		      break;
1295 		    }
1296 		}
1297 	    }
1298 #endif
1299 	  if (state == 3)
1300 	    state = 9;
1301 
1302 	  /* This is a common case.  Quickly copy CH and all the
1303 	     following symbol component or normal characters.  */
1304 	  if (to + 1 < toend
1305 	      && mri_state == NULL
1306 #if defined TC_ARM && defined OBJ_ELF
1307 	      && symver_state == NULL
1308 #endif
1309 	      )
1310 	    {
1311 	      char *s;
1312 	      int len;
1313 
1314 	      for (s = from; s < fromend; s++)
1315 		{
1316 		  int type;
1317 
1318 		  ch2 = *(unsigned char *) s;
1319 		  type = lex[ch2];
1320 		  if (type != 0
1321 		      && type != LEX_IS_SYMBOL_COMPONENT)
1322 		    break;
1323 		}
1324 
1325 	      if (s > from)
1326 		/* Handle the last character normally, for
1327 		   simplicity.  */
1328 		--s;
1329 
1330 	      len = s - from;
1331 
1332 	      if (len > (toend - to) - 1)
1333 		len = (toend - to) - 1;
1334 
1335 	      if (len > 0)
1336 		{
1337 		  PUT (ch);
1338 		  memcpy (to, from, len);
1339 		  to += len;
1340 		  from += len;
1341 		  if (to >= toend)
1342 		    goto tofull;
1343 		  ch = GET ();
1344 		}
1345 	    }
1346 
1347 	  /* Fall through.  */
1348 	default:
1349 	de_fault:
1350 	  /* Some relatively `normal' character.  */
1351 	  if (state == 0)
1352 	    {
1353 	      state = 11;	/* Now seeing label definition.  */
1354 	    }
1355 	  else if (state == 1)
1356 	    {
1357 	      state = 2;	/* Ditto.  */
1358 	    }
1359 	  else if (state == 9)
1360 	    {
1361 	      if (!IS_SYMBOL_COMPONENT (ch))
1362 		state = 3;
1363 	    }
1364 	  else if (state == 10)
1365 	    {
1366 	      if (ch == '\\')
1367 		{
1368 		  /* Special handling for backslash: a backslash may
1369 		     be the beginning of a formal parameter (of a
1370 		     macro) following another symbol character, with
1371 		     whitespace in between.  If that is the case, we
1372 		     output a space before the parameter.  Strictly
1373 		     speaking, correct handling depends upon what the
1374 		     macro parameter expands into; if the parameter
1375 		     expands into something which does not start with
1376 		     an operand character, then we don't want to keep
1377 		     the space.  We don't have enough information to
1378 		     make the right choice, so here we are making the
1379 		     choice which is more likely to be correct.  */
1380 		  PUT (' ');
1381 		}
1382 
1383 	      state = 3;
1384 	    }
1385 	  PUT (ch);
1386 	  break;
1387 	}
1388     }
1389 
1390   /*NOTREACHED*/
1391 
1392  fromeof:
1393   /* We have reached the end of the input.  */
1394   return to - tostart;
1395 
1396  tofull:
1397   /* The output buffer is full.  Save any input we have not yet
1398      processed.  */
1399   if (fromend > from)
1400     {
1401       saved_input = from;
1402       saved_input_len = fromend - from;
1403     }
1404   else
1405     saved_input = NULL;
1406 
1407   return to - tostart;
1408 }
1409 
1410