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  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, 2005, 2006, 2007, 2008, 2009, 2010, 2012
  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 3, or (at your option)
  11.    any later version.
  12.  
  13.    GAS is distributed in the hope that it will be useful, but WITHOUT
  14.    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15.    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  16.    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
  25.    excess spaces, turns single-quoted characters into a decimal
  26.    constant, and turns the # in # <number> <filename> <garbage> into a
  27.    .linefile.  This needs better error-handling.  */
  28.  
  29. #include "as.h"
  30.  
  31. #if (__STDC__ != 1)
  32. #ifndef const
  33. #define const  /* empty */
  34. #endif
  35. #endif
  36.  
  37. #ifdef H_TICK_HEX
  38. int enable_h_tick_hex = 0;
  39. #endif
  40.  
  41. #ifdef TC_M68K
  42. /* Whether we are scrubbing in m68k MRI mode.  This is different from
  43.    flag_m68k_mri, because the two flags will be affected by the .mri
  44.    pseudo-op at different times.  */
  45. static int scrub_m68k_mri;
  46.  
  47. /* The pseudo-op which switches in and out of MRI mode.  See the
  48.    comment in do_scrub_chars.  */
  49. static const char mri_pseudo[] = ".mri 0";
  50. #else
  51. #define scrub_m68k_mri 0
  52. #endif
  53.  
  54. #if defined TC_ARM && defined OBJ_ELF
  55. /* The pseudo-op for which we need to special-case `@' characters.
  56.    See the comment in do_scrub_chars.  */
  57. static const char   symver_pseudo[] = ".symver";
  58. static const char * symver_state;
  59. #endif
  60.  
  61. static char lex[256];
  62. static const char symbol_chars[] =
  63. "$._ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
  64.  
  65. #define LEX_IS_SYMBOL_COMPONENT         1
  66. #define LEX_IS_WHITESPACE               2
  67. #define LEX_IS_LINE_SEPARATOR           3
  68. #define LEX_IS_COMMENT_START            4
  69. #define LEX_IS_LINE_COMMENT_START       5
  70. #define LEX_IS_TWOCHAR_COMMENT_1ST      6
  71. #define LEX_IS_STRINGQUOTE              8
  72. #define LEX_IS_COLON                    9
  73. #define LEX_IS_NEWLINE                  10
  74. #define LEX_IS_ONECHAR_QUOTE            11
  75. #ifdef TC_V850
  76. #define LEX_IS_DOUBLEDASH_1ST           12
  77. #endif
  78. #ifdef TC_M32R
  79. #define DOUBLEBAR_PARALLEL
  80. #endif
  81. #ifdef DOUBLEBAR_PARALLEL
  82. #define LEX_IS_DOUBLEBAR_1ST            13
  83. #endif
  84. #define LEX_IS_PARALLEL_SEPARATOR       14
  85. #ifdef H_TICK_HEX
  86. #define LEX_IS_H                        15
  87. #endif
  88. #define IS_SYMBOL_COMPONENT(c)          (lex[c] == LEX_IS_SYMBOL_COMPONENT)
  89. #define IS_WHITESPACE(c)                (lex[c] == LEX_IS_WHITESPACE)
  90. #define IS_LINE_SEPARATOR(c)            (lex[c] == LEX_IS_LINE_SEPARATOR)
  91. #define IS_PARALLEL_SEPARATOR(c)        (lex[c] == LEX_IS_PARALLEL_SEPARATOR)
  92. #define IS_COMMENT(c)                   (lex[c] == LEX_IS_COMMENT_START)
  93. #define IS_LINE_COMMENT(c)              (lex[c] == LEX_IS_LINE_COMMENT_START)
  94. #define IS_NEWLINE(c)                   (lex[c] == LEX_IS_NEWLINE)
  95.  
  96. static int process_escape (int);
  97.  
  98. /* FIXME-soon: The entire lexer/parser thingy should be
  99.    built statically at compile time rather than dynamically
  100.    each and every time the assembler is run.  xoxorich.  */
  101.  
  102. void
  103. do_scrub_begin (int m68k_mri ATTRIBUTE_UNUSED)
  104. {
  105.   const char *p;
  106.   int c;
  107.  
  108.   lex[' '] = LEX_IS_WHITESPACE;
  109.   lex['\t'] = LEX_IS_WHITESPACE;
  110.   lex['\r'] = LEX_IS_WHITESPACE;
  111.   lex['\n'] = LEX_IS_NEWLINE;
  112.   lex[':'] = LEX_IS_COLON;
  113.  
  114. #ifdef TC_M68K
  115.   scrub_m68k_mri = m68k_mri;
  116.  
  117.   if (! m68k_mri)
  118. #endif
  119.     {
  120.       lex['"'] = LEX_IS_STRINGQUOTE;
  121.  
  122. #if ! defined (TC_HPPA) && ! defined (TC_I370)
  123.       /* I370 uses single-quotes to delimit integer, float constants.  */
  124.       lex['\''] = LEX_IS_ONECHAR_QUOTE;
  125. #endif
  126.  
  127. #ifdef SINGLE_QUOTE_STRINGS
  128.       lex['\''] = LEX_IS_STRINGQUOTE;
  129. #endif
  130.     }
  131.  
  132.   /* Note: if any other character can be LEX_IS_STRINGQUOTE, the loop
  133.      in state 5 of do_scrub_chars must be changed.  */
  134.  
  135.   /* Note that these override the previous defaults, e.g. if ';' is a
  136.      comment char, then it isn't a line separator.  */
  137.   for (p = symbol_chars; *p; ++p)
  138.     lex[(unsigned char) *p] = LEX_IS_SYMBOL_COMPONENT;
  139.  
  140.   for (c = 128; c < 256; ++c)
  141.     lex[c] = LEX_IS_SYMBOL_COMPONENT;
  142.  
  143. #ifdef tc_symbol_chars
  144.   /* This macro permits the processor to specify all characters which
  145.      may appears in an operand.  This will prevent the scrubber from
  146.      discarding meaningful whitespace in certain cases.  The i386
  147.      backend uses this to support prefixes, which can confuse the
  148.      scrubber as to whether it is parsing operands or opcodes.  */
  149.   for (p = tc_symbol_chars; *p; ++p)
  150.     lex[(unsigned char) *p] = LEX_IS_SYMBOL_COMPONENT;
  151. #endif
  152.  
  153.   /* The m68k backend wants to be able to change comment_chars.  */
  154. #ifndef tc_comment_chars
  155. #define tc_comment_chars comment_chars
  156. #endif
  157.   for (p = tc_comment_chars; *p; p++)
  158.     lex[(unsigned char) *p] = LEX_IS_COMMENT_START;
  159.  
  160.   for (p = line_comment_chars; *p; p++)
  161.     lex[(unsigned char) *p] = LEX_IS_LINE_COMMENT_START;
  162.  
  163.   for (p = line_separator_chars; *p; p++)
  164.     lex[(unsigned char) *p] = LEX_IS_LINE_SEPARATOR;
  165.  
  166. #ifdef tc_parallel_separator_chars
  167.   /* This macro permits the processor to specify all characters which
  168.      separate parallel insns on the same line.  */
  169.   for (p = tc_parallel_separator_chars; *p; p++)
  170.     lex[(unsigned char) *p] = LEX_IS_PARALLEL_SEPARATOR;
  171. #endif
  172.  
  173.   /* Only allow slash-star comments if slash is not in use.
  174.      FIXME: This isn't right.  We should always permit them.  */
  175.   if (lex['/'] == 0)
  176.     lex['/'] = LEX_IS_TWOCHAR_COMMENT_1ST;
  177.  
  178. #ifdef TC_M68K
  179.   if (m68k_mri)
  180.     {
  181.       lex['\''] = LEX_IS_STRINGQUOTE;
  182.       lex[';'] = LEX_IS_COMMENT_START;
  183.       lex['*'] = LEX_IS_LINE_COMMENT_START;
  184.       /* The MRI documentation says '!' is LEX_IS_COMMENT_START, but
  185.          then it can't be used in an expression.  */
  186.       lex['!'] = LEX_IS_LINE_COMMENT_START;
  187.     }
  188. #endif
  189.  
  190. #ifdef TC_V850
  191.   lex['-'] = LEX_IS_DOUBLEDASH_1ST;
  192. #endif
  193. #ifdef DOUBLEBAR_PARALLEL
  194.   lex['|'] = LEX_IS_DOUBLEBAR_1ST;
  195. #endif
  196. #ifdef TC_D30V
  197.   /* Must do this is we want VLIW instruction with "->" or "<-".  */
  198.   lex['-'] = LEX_IS_SYMBOL_COMPONENT;
  199. #endif
  200.  
  201. #ifdef H_TICK_HEX
  202.   if (enable_h_tick_hex)
  203.     {
  204.       lex['h'] = LEX_IS_H;
  205.       lex['H'] = LEX_IS_H;
  206.     }
  207. #endif
  208. }
  209.  
  210. /* Saved state of the scrubber.  */
  211. static int state;
  212. static int old_state;
  213. static char *out_string;
  214. static char out_buf[20];
  215. static int add_newlines;
  216. static char *saved_input;
  217. static size_t saved_input_len;
  218. static char input_buffer[32 * 1024];
  219. static const char *mri_state;
  220. static char mri_last_ch;
  221.  
  222. /* Data structure for saving the state of app across #include's.  Note that
  223.    app is called asynchronously to the parsing of the .include's, so our
  224.    state at the time .include is interpreted is completely unrelated.
  225.    That's why we have to save it all.  */
  226.  
  227. struct app_save
  228. {
  229.   int          state;
  230.   int          old_state;
  231.   char *       out_string;
  232.   char         out_buf[sizeof (out_buf)];
  233.   int          add_newlines;
  234.   char *       saved_input;
  235.   size_t       saved_input_len;
  236. #ifdef TC_M68K
  237.   int          scrub_m68k_mri;
  238. #endif
  239.   const char * mri_state;
  240.   char         mri_last_ch;
  241. #if defined TC_ARM && defined OBJ_ELF
  242.   const char * symver_state;
  243. #endif
  244. };
  245.  
  246. char *
  247. app_push (void)
  248. {
  249.   register struct app_save *saved;
  250.  
  251.   saved = (struct app_save *) xmalloc (sizeof (*saved));
  252.   saved->state = state;
  253.   saved->old_state = old_state;
  254.   saved->out_string = out_string;
  255.   memcpy (saved->out_buf, out_buf, sizeof (out_buf));
  256.   saved->add_newlines = add_newlines;
  257.   if (saved_input == NULL)
  258.     saved->saved_input = NULL;
  259.   else
  260.     {
  261.       saved->saved_input = (char *) xmalloc (saved_input_len);
  262.       memcpy (saved->saved_input, saved_input, saved_input_len);
  263.       saved->saved_input_len = saved_input_len;
  264.     }
  265. #ifdef TC_M68K
  266.   saved->scrub_m68k_mri = scrub_m68k_mri;
  267. #endif
  268.   saved->mri_state = mri_state;
  269.   saved->mri_last_ch = mri_last_ch;
  270. #if defined TC_ARM && defined OBJ_ELF
  271.   saved->symver_state = symver_state;
  272. #endif
  273.  
  274.   /* do_scrub_begin() is not useful, just wastes time.  */
  275.  
  276.   state = 0;
  277.   saved_input = NULL;
  278.   add_newlines = 0;
  279.  
  280.   return (char *) saved;
  281. }
  282.  
  283. void
  284. app_pop (char *arg)
  285. {
  286.   register struct app_save *saved = (struct app_save *) arg;
  287.  
  288.   /* There is no do_scrub_end ().  */
  289.   state = saved->state;
  290.   old_state = saved->old_state;
  291.   out_string = saved->out_string;
  292.   memcpy (out_buf, saved->out_buf, sizeof (out_buf));
  293.   add_newlines = saved->add_newlines;
  294.   if (saved->saved_input == NULL)
  295.     saved_input = NULL;
  296.   else
  297.     {
  298.       gas_assert (saved->saved_input_len <= sizeof (input_buffer));
  299.       memcpy (input_buffer, saved->saved_input, saved->saved_input_len);
  300.       saved_input = input_buffer;
  301.       saved_input_len = saved->saved_input_len;
  302.       free (saved->saved_input);
  303.     }
  304. #ifdef TC_M68K
  305.   scrub_m68k_mri = saved->scrub_m68k_mri;
  306. #endif
  307.   mri_state = saved->mri_state;
  308.   mri_last_ch = saved->mri_last_ch;
  309. #if defined TC_ARM && defined OBJ_ELF
  310.   symver_state = saved->symver_state;
  311. #endif
  312.  
  313.   free (arg);
  314. }
  315.  
  316. /* @@ This assumes that \n &c are the same on host and target.  This is not
  317.    necessarily true.  */
  318.  
  319. static int
  320. process_escape (int ch)
  321. {
  322.   switch (ch)
  323.     {
  324.     case 'b':
  325.       return '\b';
  326.     case 'f':
  327.       return '\f';
  328.     case 'n':
  329.       return '\n';
  330.     case 'r':
  331.       return '\r';
  332.     case 't':
  333.       return '\t';
  334.     case '\'':
  335.       return '\'';
  336.     case '"':
  337.       return '\"';
  338.     default:
  339.       return ch;
  340.     }
  341. }
  342.  
  343. /* This function is called to process input characters.  The GET
  344.    parameter is used to retrieve more input characters.  GET should
  345.    set its parameter to point to a buffer, and return the length of
  346.    the buffer; it should return 0 at end of file.  The scrubbed output
  347.    characters are put into the buffer starting at TOSTART; the TOSTART
  348.    buffer is TOLEN bytes in length.  The function returns the number
  349.    of scrubbed characters put into TOSTART.  This will be TOLEN unless
  350.    end of file was seen.  This function is arranged as a state
  351.    machine, and saves its state so that it may return at any point.
  352.    This is the way the old code used to work.  */
  353.  
  354. size_t
  355. do_scrub_chars (size_t (*get) (char *, size_t), char *tostart, size_t tolen)
  356. {
  357.   char *to = tostart;
  358.   char *toend = tostart + tolen;
  359.   char *from;
  360.   char *fromend;
  361.   size_t fromlen;
  362.   register int ch, ch2 = 0;
  363.   /* Character that started the string we're working on.  */
  364.   static char quotechar;
  365.  
  366.   /*State 0: beginning of normal line
  367.           1: After first whitespace on line (flush more white)
  368.           2: After first non-white (opcode) on line (keep 1white)
  369.           3: after second white on line (into operands) (flush white)
  370.           4: after putting out a .linefile, put out digits
  371.           5: parsing a string, then go to old-state
  372.           6: putting out \ escape in a "d string.
  373.           7: no longer used
  374.           8: no longer used
  375.           9: After seeing symbol char in state 3 (keep 1white after symchar)
  376.          10: After seeing whitespace in state 9 (keep white before symchar)
  377.          11: After seeing a symbol character in state 0 (eg a label definition)
  378.          -1: output string in out_string and go to the state in old_state
  379.          -2: flush text until a '*' '/' is seen, then go to state old_state
  380. #ifdef TC_V850
  381.          12: After seeing a dash, looking for a second dash as a start
  382.              of comment.
  383. #endif
  384. #ifdef DOUBLEBAR_PARALLEL
  385.          13: After seeing a vertical bar, looking for a second
  386.              vertical bar as a parallel expression separator.
  387. #endif
  388. #ifdef TC_PREDICATE_START_CHAR
  389.          14: After seeing a predicate start character at state 0, looking
  390.              for a predicate end character as predicate.
  391.          15: After seeing a predicate start character at state 1, looking
  392.              for a predicate end character as predicate.
  393. #endif
  394. #ifdef TC_Z80
  395.          16: After seeing an 'a' or an 'A' at the start of a symbol
  396.          17: After seeing an 'f' or an 'F' in state 16
  397. #endif
  398.           */
  399.  
  400.   /* I added states 9 and 10 because the MIPS ECOFF assembler uses
  401.      constructs like ``.loc 1 20''.  This was turning into ``.loc
  402.      120''.  States 9 and 10 ensure that a space is never dropped in
  403.      between characters which could appear in an identifier.  Ian
  404.      Taylor, ian@cygnus.com.
  405.  
  406.      I added state 11 so that something like "Lfoo add %r25,%r26,%r27" works
  407.      correctly on the PA (and any other target where colons are optional).
  408.      Jeff Law, law@cs.utah.edu.
  409.  
  410.      I added state 13 so that something like "cmp r1, r2 || trap #1" does not
  411.      get squashed into "cmp r1,r2||trap#1", with the all important space
  412.      between the 'trap' and the '#1' being eliminated.  nickc@cygnus.com  */
  413.  
  414.   /* This macro gets the next input character.  */
  415.  
  416. #define GET()                                                   \
  417.   (from < fromend                                               \
  418.    ? * (unsigned char *) (from++)                               \
  419.    : (saved_input = NULL,                                       \
  420.       fromlen = (*get) (input_buffer, sizeof input_buffer),     \
  421.       from = input_buffer,                                      \
  422.       fromend = from + fromlen,                                 \
  423.       (fromlen == 0                                             \
  424.        ? EOF                                                    \
  425.        : * (unsigned char *) (from++))))
  426.  
  427.   /* This macro pushes a character back on the input stream.  */
  428.  
  429. #define UNGET(uch) (*--from = (uch))
  430.  
  431.   /* This macro puts a character into the output buffer.  If this
  432.      character fills the output buffer, this macro jumps to the label
  433.      TOFULL.  We use this rather ugly approach because we need to
  434.      handle two different termination conditions: EOF on the input
  435.      stream, and a full output buffer.  It would be simpler if we
  436.      always read in the entire input stream before processing it, but
  437.      I don't want to make such a significant change to the assembler's
  438.      memory usage.  */
  439.  
  440. #define PUT(pch)                                \
  441.   do                                            \
  442.     {                                           \
  443.       *to++ = (pch);                            \
  444.       if (to >= toend)                          \
  445.         goto tofull;                            \
  446.     }                                           \
  447.   while (0)
  448.  
  449.   if (saved_input != NULL)
  450.     {
  451.       from = saved_input;
  452.       fromend = from + saved_input_len;
  453.     }
  454.   else
  455.     {
  456.       fromlen = (*get) (input_buffer, sizeof input_buffer);
  457.       if (fromlen == 0)
  458.         return 0;
  459.       from = input_buffer;
  460.       fromend = from + fromlen;
  461.     }
  462.  
  463.   while (1)
  464.     {
  465.       /* The cases in this switch end with continue, in order to
  466.          branch back to the top of this while loop and generate the
  467.          next output character in the appropriate state.  */
  468.       switch (state)
  469.         {
  470.         case -1:
  471.           ch = *out_string++;
  472.           if (*out_string == '\0')
  473.             {
  474.               state = old_state;
  475.               old_state = 3;
  476.             }
  477.           PUT (ch);
  478.           continue;
  479.  
  480.         case -2:
  481.           for (;;)
  482.             {
  483.               do
  484.                 {
  485.                   ch = GET ();
  486.  
  487.                   if (ch == EOF)
  488.                     {
  489.                       as_warn (_("end of file in comment"));
  490.                       goto fromeof;
  491.                     }
  492.  
  493.                   if (ch == '\n')
  494.                     PUT ('\n');
  495.                 }
  496.               while (ch != '*');
  497.  
  498.               while ((ch = GET ()) == '*')
  499.                 ;
  500.  
  501.               if (ch == EOF)
  502.                 {
  503.                   as_warn (_("end of file in comment"));
  504.                   goto fromeof;
  505.                 }
  506.  
  507.               if (ch == '/')
  508.                 break;
  509.  
  510.               UNGET (ch);
  511.             }
  512.  
  513.           state = old_state;
  514.           UNGET (' ');
  515.           continue;
  516.  
  517.         case 4:
  518.           ch = GET ();
  519.           if (ch == EOF)
  520.             goto fromeof;
  521.           else if (ch >= '0' && ch <= '9')
  522.             PUT (ch);
  523.           else
  524.             {
  525.               while (ch != EOF && IS_WHITESPACE (ch))
  526.                 ch = GET ();
  527.               if (ch == '"')
  528.                 {
  529.                   quotechar = ch;
  530.                   state = 5;
  531.                   old_state = 3;
  532.                   PUT (ch);
  533.                 }
  534.               else
  535.                 {
  536.                   while (ch != EOF && ch != '\n')
  537.                     ch = GET ();
  538.                   state = 0;
  539.                   PUT (ch);
  540.                 }
  541.             }
  542.           continue;
  543.  
  544.         case 5:
  545.           /* We are going to copy everything up to a quote character,
  546.              with special handling for a backslash.  We try to
  547.              optimize the copying in the simple case without using the
  548.              GET and PUT macros.  */
  549.           {
  550.             char *s;
  551.             ptrdiff_t len;
  552.  
  553.             for (s = from; s < fromend; s++)
  554.               {
  555.                 ch = *s;
  556.                 if (ch == '\\'
  557.                     || ch == quotechar
  558.                     || ch == '\n')
  559.                   break;
  560.               }
  561.             len = s - from;
  562.             if (len > toend - to)
  563.               len = toend - to;
  564.             if (len > 0)
  565.               {
  566.                 memcpy (to, from, len);
  567.                 to += len;
  568.                 from += len;
  569.                 if (to >= toend)
  570.                   goto tofull;
  571.               }
  572.           }
  573.  
  574.           ch = GET ();
  575.           if (ch == EOF)
  576.             {
  577.               /* This buffer is here specifically so
  578.                  that the UNGET below will work.  */
  579.               static char one_char_buf[1];
  580.  
  581.               as_warn (_("end of file in string; '%c' inserted"), quotechar);
  582.               state = old_state;
  583.               from = fromend = one_char_buf + 1;
  584.               fromlen = 1;
  585.               UNGET ('\n');
  586.               PUT (quotechar);
  587.             }
  588.           else if (ch == quotechar)
  589.             {
  590.               state = old_state;
  591.               PUT (ch);
  592.             }
  593. #ifndef NO_STRING_ESCAPES
  594.           else if (ch == '\\')
  595.             {
  596.               state = 6;
  597.               PUT (ch);
  598.             }
  599. #endif
  600.           else if (scrub_m68k_mri && ch == '\n')
  601.             {
  602.               /* Just quietly terminate the string.  This permits lines like
  603.                    bne  label   loop if we haven't reach end yet.  */
  604.               state = old_state;
  605.               UNGET (ch);
  606.               PUT ('\'');
  607.             }
  608.           else
  609.             {
  610.               PUT (ch);
  611.             }
  612.           continue;
  613.  
  614.         case 6:
  615.           state = 5;
  616.           ch = GET ();
  617.           switch (ch)
  618.             {
  619.               /* Handle strings broken across lines, by turning '\n' into
  620.                  '\\' and 'n'.  */
  621.             case '\n':
  622.               UNGET ('n');
  623.               add_newlines++;
  624.               PUT ('\\');
  625.               continue;
  626.  
  627.             case EOF:
  628.               as_warn (_("end of file in string; '%c' inserted"), quotechar);
  629.               PUT (quotechar);
  630.               continue;
  631.  
  632.             case '"':
  633.             case '\\':
  634.             case 'b':
  635.             case 'f':
  636.             case 'n':
  637.             case 'r':
  638.             case 't':
  639.             case 'v':
  640.             case 'x':
  641.             case 'X':
  642.             case '0':
  643.             case '1':
  644.             case '2':
  645.             case '3':
  646.             case '4':
  647.             case '5':
  648.             case '6':
  649.             case '7':
  650.               break;
  651.  
  652.             default:
  653. #ifdef ONLY_STANDARD_ESCAPES
  654.               as_warn (_("unknown escape '\\%c' in string; ignored"), ch);
  655. #endif
  656.               break;
  657.             }
  658.           PUT (ch);
  659.           continue;
  660.  
  661. #ifdef DOUBLEBAR_PARALLEL
  662.         case 13:
  663.           ch = GET ();
  664.           if (ch != '|')
  665.             abort ();
  666.  
  667.           /* Reset back to state 1 and pretend that we are parsing a
  668.              line from just after the first white space.  */
  669.           state = 1;
  670.           PUT ('|');
  671. #ifdef TC_TIC6X
  672.           /* "||^" is used for SPMASKed instructions.  */
  673.           ch = GET ();
  674.           if (ch == EOF)
  675.             goto fromeof;
  676.           else if (ch == '^')
  677.             PUT ('^');
  678.           else
  679.             UNGET (ch);
  680. #endif
  681.           continue;
  682. #endif
  683. #ifdef TC_Z80
  684.         case 16:
  685.           /* We have seen an 'a' at the start of a symbol, look for an 'f'.  */
  686.           ch = GET ();
  687.           if (ch == 'f' || ch == 'F')
  688.             {
  689.               state = 17;
  690.               PUT (ch);
  691.             }
  692.           else
  693.             {
  694.               state = 9;
  695.               break;
  696.             }
  697.         case 17:
  698.           /* We have seen "af" at the start of a symbol,
  699.              a ' here is a part of that symbol.  */
  700.           ch = GET ();
  701.           state = 9;
  702.           if (ch == '\'')
  703.             /* Change to avoid warning about unclosed string.  */
  704.             PUT ('`');
  705.           else if (ch != EOF)
  706.             UNGET (ch);
  707.           break;
  708. #endif
  709.         }
  710.  
  711.       /* OK, we are somewhere in states 0 through 4 or 9 through 11.  */
  712.  
  713.       /* flushchar: */
  714.       ch = GET ();
  715.  
  716. #ifdef TC_PREDICATE_START_CHAR
  717.       if (ch == TC_PREDICATE_START_CHAR && (state == 0 || state == 1))
  718.         {
  719.           state += 14;
  720.           PUT (ch);
  721.           continue;
  722.         }
  723.       else if (state == 14 || state == 15)
  724.         {
  725.           if (ch == TC_PREDICATE_END_CHAR)
  726.             {
  727.               state -= 14;
  728.               PUT (ch);
  729.               ch = GET ();
  730.             }
  731.           else
  732.             {
  733.               PUT (ch);
  734.               continue;
  735.             }
  736.         }
  737. #endif
  738.  
  739.     recycle:
  740.  
  741. #if defined TC_ARM && defined OBJ_ELF
  742.       /* We need to watch out for .symver directives.  See the comment later
  743.          in this function.  */
  744.       if (symver_state == NULL)
  745.         {
  746.           if ((state == 0 || state == 1) && ch == symver_pseudo[0])
  747.             symver_state = symver_pseudo + 1;
  748.         }
  749.       else
  750.         {
  751.           /* We advance to the next state if we find the right
  752.              character.  */
  753.           if (ch != '\0' && (*symver_state == ch))
  754.             ++symver_state;
  755.           else if (*symver_state != '\0')
  756.             /* We did not get the expected character, or we didn't
  757.                get a valid terminating character after seeing the
  758.                entire pseudo-op, so we must go back to the beginning.  */
  759.             symver_state = NULL;
  760.           else
  761.             {
  762.               /* We've read the entire pseudo-op.  If this is the end
  763.                  of the line, go back to the beginning.  */
  764.               if (IS_NEWLINE (ch))
  765.                 symver_state = NULL;
  766.             }
  767.         }
  768. #endif /* TC_ARM && OBJ_ELF */
  769.  
  770. #ifdef TC_M68K
  771.       /* We want to have pseudo-ops which control whether we are in
  772.          MRI mode or not.  Unfortunately, since m68k MRI mode affects
  773.          the scrubber, that means that we need a special purpose
  774.          recognizer here.  */
  775.       if (mri_state == NULL)
  776.         {
  777.           if ((state == 0 || state == 1)
  778.               && ch == mri_pseudo[0])
  779.             mri_state = mri_pseudo + 1;
  780.         }
  781.       else
  782.         {
  783.           /* We advance to the next state if we find the right
  784.              character, or if we need a space character and we get any
  785.              whitespace character, or if we need a '0' and we get a
  786.              '1' (this is so that we only need one state to handle
  787.              ``.mri 0'' and ``.mri 1'').  */
  788.           if (ch != '\0'
  789.               && (*mri_state == ch
  790.                   || (*mri_state == ' '
  791.                       && lex[ch] == LEX_IS_WHITESPACE)
  792.                   || (*mri_state == '0'
  793.                       && ch == '1')))
  794.             {
  795.               mri_last_ch = ch;
  796.               ++mri_state;
  797.             }
  798.           else if (*mri_state != '\0'
  799.                    || (lex[ch] != LEX_IS_WHITESPACE
  800.                        && lex[ch] != LEX_IS_NEWLINE))
  801.             {
  802.               /* We did not get the expected character, or we didn't
  803.                  get a valid terminating character after seeing the
  804.                  entire pseudo-op, so we must go back to the
  805.                  beginning.  */
  806.               mri_state = NULL;
  807.             }
  808.           else
  809.             {
  810.               /* We've read the entire pseudo-op.  mips_last_ch is
  811.                  either '0' or '1' indicating whether to enter or
  812.                  leave MRI mode.  */
  813.               do_scrub_begin (mri_last_ch == '1');
  814.               mri_state = NULL;
  815.  
  816.               /* We continue handling the character as usual.  The
  817.                  main gas reader must also handle the .mri pseudo-op
  818.                  to control expression parsing and the like.  */
  819.             }
  820.         }
  821. #endif
  822.  
  823.       if (ch == EOF)
  824.         {
  825.           if (state != 0)
  826.             {
  827.               as_warn (_("end of file not at end of a line; newline inserted"));
  828.               state = 0;
  829.               PUT ('\n');
  830.             }
  831.           goto fromeof;
  832.         }
  833.  
  834.       switch (lex[ch])
  835.         {
  836.         case LEX_IS_WHITESPACE:
  837.           do
  838.             {
  839.               ch = GET ();
  840.             }
  841.           while (ch != EOF && IS_WHITESPACE (ch));
  842.           if (ch == EOF)
  843.             goto fromeof;
  844.  
  845.           if (state == 0)
  846.             {
  847.               /* Preserve a single whitespace character at the
  848.                  beginning of a line.  */
  849.               state = 1;
  850.               UNGET (ch);
  851.               PUT (' ');
  852.               break;
  853.             }
  854.  
  855. #ifdef KEEP_WHITE_AROUND_COLON
  856.           if (lex[ch] == LEX_IS_COLON)
  857.             {
  858.               /* Only keep this white if there's no white *after* the
  859.                  colon.  */
  860.               ch2 = GET ();
  861.               if (ch2 != EOF)
  862.                 UNGET (ch2);
  863.               if (!IS_WHITESPACE (ch2))
  864.                 {
  865.                   state = 9;
  866.                   UNGET (ch);
  867.                   PUT (' ');
  868.                   break;
  869.                 }
  870.             }
  871. #endif
  872.           if (IS_COMMENT (ch)
  873.               || ch == '/'
  874.               || IS_LINE_SEPARATOR (ch)
  875.               || IS_PARALLEL_SEPARATOR (ch))
  876.             {
  877.               if (scrub_m68k_mri)
  878.                 {
  879.                   /* In MRI mode, we keep these spaces.  */
  880.                   UNGET (ch);
  881.                   PUT (' ');
  882.                   break;
  883.                 }
  884.               goto recycle;
  885.             }
  886.  
  887.           /* If we're in state 2 or 11, we've seen a non-white
  888.              character followed by whitespace.  If the next character
  889.              is ':', this is whitespace after a label name which we
  890.              normally must ignore.  In MRI mode, though, spaces are
  891.              not permitted between the label and the colon.  */
  892.           if ((state == 2 || state == 11)
  893.               && lex[ch] == LEX_IS_COLON
  894.               && ! scrub_m68k_mri)
  895.             {
  896.               state = 1;
  897.               PUT (ch);
  898.               break;
  899.             }
  900.  
  901.           switch (state)
  902.             {
  903.             case 1:
  904.               /* We can arrive here if we leave a leading whitespace
  905.                  character at the beginning of a line.  */
  906.               goto recycle;
  907.             case 2:
  908.               state = 3;
  909.               if (to + 1 < toend)
  910.                 {
  911.                   /* Optimize common case by skipping UNGET/GET.  */
  912.                   PUT (' ');    /* Sp after opco */
  913.                   goto recycle;
  914.                 }
  915.               UNGET (ch);
  916.               PUT (' ');
  917.               break;
  918.             case 3:
  919. #ifndef TC_KEEP_OPERAND_SPACES
  920.               /* For TI C6X, we keep these spaces as they may separate
  921.                  functional unit specifiers from operands.  */
  922.               if (scrub_m68k_mri)
  923. #endif
  924.                 {
  925.                   /* In MRI mode, we keep these spaces.  */
  926.                   UNGET (ch);
  927.                   PUT (' ');
  928.                   break;
  929.                 }
  930.               goto recycle;     /* Sp in operands */
  931.             case 9:
  932.             case 10:
  933. #ifndef TC_KEEP_OPERAND_SPACES
  934.               if (scrub_m68k_mri)
  935. #endif
  936.                 {
  937.                   /* In MRI mode, we keep these spaces.  */
  938.                   state = 3;
  939.                   UNGET (ch);
  940.                   PUT (' ');
  941.                   break;
  942.                 }
  943.               state = 10;       /* Sp after symbol char */
  944.               goto recycle;
  945.             case 11:
  946.               if (LABELS_WITHOUT_COLONS || flag_m68k_mri)
  947.                 state = 1;
  948.               else
  949.                 {
  950.                   /* We know that ch is not ':', since we tested that
  951.                      case above.  Therefore this is not a label, so it
  952.                      must be the opcode, and we've just seen the
  953.                      whitespace after it.  */
  954.                   state = 3;
  955.                 }
  956.               UNGET (ch);
  957.               PUT (' ');        /* Sp after label definition.  */
  958.               break;
  959.             default:
  960.               BAD_CASE (state);
  961.             }
  962.           break;
  963.  
  964.         case LEX_IS_TWOCHAR_COMMENT_1ST:
  965.           ch2 = GET ();
  966.           if (ch2 == '*')
  967.             {
  968.               for (;;)
  969.                 {
  970.                   do
  971.                     {
  972.                       ch2 = GET ();
  973.                       if (ch2 != EOF && IS_NEWLINE (ch2))
  974.                         add_newlines++;
  975.                     }
  976.                   while (ch2 != EOF && ch2 != '*');
  977.  
  978.                   while (ch2 == '*')
  979.                     ch2 = GET ();
  980.  
  981.                   if (ch2 == EOF || ch2 == '/')
  982.                     break;
  983.  
  984.                   /* This UNGET will ensure that we count newlines
  985.                      correctly.  */
  986.                   UNGET (ch2);
  987.                 }
  988.  
  989.               if (ch2 == EOF)
  990.                 as_warn (_("end of file in multiline comment"));
  991.  
  992.               ch = ' ';
  993.               goto recycle;
  994.             }
  995. #ifdef DOUBLESLASH_LINE_COMMENTS
  996.           else if (ch2 == '/')
  997.             {
  998.               do
  999.                 {
  1000.                   ch = GET ();
  1001.                 }
  1002.               while (ch != EOF && !IS_NEWLINE (ch));
  1003.               if (ch == EOF)
  1004.                 as_warn ("end of file in comment; newline inserted");
  1005.               state = 0;
  1006.               PUT ('\n');
  1007.               break;
  1008.             }
  1009. #endif
  1010.           else
  1011.             {
  1012.               if (ch2 != EOF)
  1013.                 UNGET (ch2);
  1014.               if (state == 9 || state == 10)
  1015.                 state = 3;
  1016.               PUT (ch);
  1017.             }
  1018.           break;
  1019.  
  1020.         case LEX_IS_STRINGQUOTE:
  1021.           quotechar = ch;
  1022.           if (state == 10)
  1023.             {
  1024.               /* Preserve the whitespace in foo "bar".  */
  1025.               UNGET (ch);
  1026.               state = 3;
  1027.               PUT (' ');
  1028.  
  1029.               /* PUT didn't jump out.  We could just break, but we
  1030.                  know what will happen, so optimize a bit.  */
  1031.               ch = GET ();
  1032.               old_state = 3;
  1033.             }
  1034.           else if (state == 9)
  1035.             old_state = 3;
  1036.           else
  1037.             old_state = state;
  1038.           state = 5;
  1039.           PUT (ch);
  1040.           break;
  1041.  
  1042. #ifndef IEEE_STYLE
  1043.         case LEX_IS_ONECHAR_QUOTE:
  1044. #ifdef H_TICK_HEX
  1045.           if (state == 9 && enable_h_tick_hex)
  1046.             {
  1047.               char c;
  1048.  
  1049.               c = GET ();
  1050.               as_warn ("'%c found after symbol", c);
  1051.               UNGET (c);
  1052.             }
  1053. #endif
  1054.           if (state == 10)
  1055.             {
  1056.               /* Preserve the whitespace in foo 'b'.  */
  1057.               UNGET (ch);
  1058.               state = 3;
  1059.               PUT (' ');
  1060.               break;
  1061.             }
  1062.           ch = GET ();
  1063.           if (ch == EOF)
  1064.             {
  1065.               as_warn (_("end of file after a one-character quote; \\0 inserted"));
  1066.               ch = 0;
  1067.             }
  1068.           if (ch == '\\')
  1069.             {
  1070.               ch = GET ();
  1071.               if (ch == EOF)
  1072.                 {
  1073.                   as_warn (_("end of file in escape character"));
  1074.                   ch = '\\';
  1075.                 }
  1076.               else
  1077.                 ch = process_escape (ch);
  1078.             }
  1079.           sprintf (out_buf, "%d", (int) (unsigned char) ch);
  1080.  
  1081.           /* None of these 'x constants for us.  We want 'x'.  */
  1082.           if ((ch = GET ()) != '\'')
  1083.             {
  1084. #ifdef REQUIRE_CHAR_CLOSE_QUOTE
  1085.               as_warn (_("missing close quote; (assumed)"));
  1086. #else
  1087.               if (ch != EOF)
  1088.                 UNGET (ch);
  1089. #endif
  1090.             }
  1091.           if (strlen (out_buf) == 1)
  1092.             {
  1093.               PUT (out_buf[0]);
  1094.               break;
  1095.             }
  1096.           if (state == 9)
  1097.             old_state = 3;
  1098.           else
  1099.             old_state = state;
  1100.           state = -1;
  1101.           out_string = out_buf;
  1102.           PUT (*out_string++);
  1103.           break;
  1104. #endif
  1105.  
  1106.         case LEX_IS_COLON:
  1107. #ifdef KEEP_WHITE_AROUND_COLON
  1108.           state = 9;
  1109. #else
  1110.           if (state == 9 || state == 10)
  1111.             state = 3;
  1112.           else if (state != 3)
  1113.             state = 1;
  1114. #endif
  1115.           PUT (ch);
  1116.           break;
  1117.  
  1118.         case LEX_IS_NEWLINE:
  1119.           /* Roll out a bunch of newlines from inside comments, etc.  */
  1120.           if (add_newlines)
  1121.             {
  1122.               --add_newlines;
  1123.               UNGET (ch);
  1124.             }
  1125.           /* Fall through.  */
  1126.  
  1127.         case LEX_IS_LINE_SEPARATOR:
  1128.           state = 0;
  1129.           PUT (ch);
  1130.           break;
  1131.  
  1132.         case LEX_IS_PARALLEL_SEPARATOR:
  1133.           state = 1;
  1134.           PUT (ch);
  1135.           break;
  1136.  
  1137. #ifdef TC_V850
  1138.         case LEX_IS_DOUBLEDASH_1ST:
  1139.           ch2 = GET ();
  1140.           if (ch2 != '-')
  1141.             {
  1142.               if (ch2 != EOF)
  1143.                 UNGET (ch2);
  1144.               goto de_fault;
  1145.             }
  1146.           /* Read and skip to end of line.  */
  1147.           do
  1148.             {
  1149.               ch = GET ();
  1150.             }
  1151.           while (ch != EOF && ch != '\n');
  1152.  
  1153.           if (ch == EOF)
  1154.             as_warn (_("end of file in comment; newline inserted"));
  1155.  
  1156.           state = 0;
  1157.           PUT ('\n');
  1158.           break;
  1159. #endif
  1160. #ifdef DOUBLEBAR_PARALLEL
  1161.         case LEX_IS_DOUBLEBAR_1ST:
  1162.           ch2 = GET ();
  1163.           if (ch2 != EOF)
  1164.             UNGET (ch2);
  1165.           if (ch2 != '|')
  1166.             goto de_fault;
  1167.  
  1168.           /* Handle '||' in two states as invoking PUT twice might
  1169.              result in the first one jumping out of this loop.  We'd
  1170.              then lose track of the state and one '|' char.  */
  1171.           state = 13;
  1172.           PUT ('|');
  1173.           break;
  1174. #endif
  1175.         case LEX_IS_LINE_COMMENT_START:
  1176.           /* FIXME-someday: The two character comment stuff was badly
  1177.              thought out.  On i386, we want '/' as line comment start
  1178.              AND we want C style comments.  hence this hack.  The
  1179.              whole lexical process should be reworked.  xoxorich.  */
  1180.           if (ch == '/')
  1181.             {
  1182.               ch2 = GET ();
  1183.               if (ch2 == '*')
  1184.                 {
  1185.                   old_state = 3;
  1186.                   state = -2;
  1187.                   break;
  1188.                 }
  1189.               else
  1190.                 {
  1191.                   UNGET (ch2);
  1192.                 }
  1193.             }
  1194.  
  1195.           if (state == 0 || state == 1) /* Only comment at start of line.  */
  1196.             {
  1197.               int startch;
  1198.  
  1199.               startch = ch;
  1200.  
  1201.               do
  1202.                 {
  1203.                   ch = GET ();
  1204.                 }
  1205.               while (ch != EOF && IS_WHITESPACE (ch));
  1206.  
  1207.               if (ch == EOF)
  1208.                 {
  1209.                   as_warn (_("end of file in comment; newline inserted"));
  1210.                   PUT ('\n');
  1211.                   break;
  1212.                 }
  1213.  
  1214.               if (ch < '0' || ch > '9' || state != 0 || startch != '#')
  1215.                 {
  1216.                   /* Not a cpp line.  */
  1217.                   while (ch != EOF && !IS_NEWLINE (ch))
  1218.                     ch = GET ();
  1219.                   if (ch == EOF)
  1220.                     as_warn (_("end of file in comment; newline inserted"));
  1221.                   state = 0;
  1222.                   PUT ('\n');
  1223.                   break;
  1224.                 }
  1225.               /* Looks like `# 123 "filename"' from cpp.  */
  1226.               UNGET (ch);
  1227.               old_state = 4;
  1228.               state = -1;
  1229.               if (scrub_m68k_mri)
  1230.                 out_string = "\tlinefile ";
  1231.               else
  1232.                 out_string = "\t.linefile ";
  1233.               PUT (*out_string++);
  1234.               break;
  1235.             }
  1236.  
  1237. #ifdef TC_D10V
  1238.           /* All insns end in a char for which LEX_IS_SYMBOL_COMPONENT is true.
  1239.              Trap is the only short insn that has a first operand that is
  1240.              neither register nor label.
  1241.              We must prevent exef0f ||trap #1 to degenerate to exef0f ||trap#1 .
  1242.              We can't make '#' LEX_IS_SYMBOL_COMPONENT because it is
  1243.              already LEX_IS_LINE_COMMENT_START.  However, it is the
  1244.              only character in line_comment_chars for d10v, hence we
  1245.              can recognize it as such.  */
  1246.           /* An alternative approach would be to reset the state to 1 when
  1247.              we see '||', '<'- or '->', but that seems to be overkill.  */
  1248.           if (state == 10)
  1249.             PUT (' ');
  1250. #endif
  1251.           /* We have a line comment character which is not at the
  1252.              start of a line.  If this is also a normal comment
  1253.              character, fall through.  Otherwise treat it as a default
  1254.              character.  */
  1255.           if (strchr (tc_comment_chars, ch) == NULL
  1256.               && (! scrub_m68k_mri
  1257.                   || (ch != '!' && ch != '*')))
  1258.             goto de_fault;
  1259.           if (scrub_m68k_mri
  1260.               && (ch == '!' || ch == '*' || ch == '#')
  1261.               && state != 1
  1262.               && state != 10)
  1263.             goto de_fault;
  1264.           /* Fall through.  */
  1265.         case LEX_IS_COMMENT_START:
  1266. #if defined TC_ARM && defined OBJ_ELF
  1267.           /* On the ARM, `@' is the comment character.
  1268.              Unfortunately this is also a special character in ELF .symver
  1269.              directives (and .type, though we deal with those another way).
  1270.              So we check if this line is such a directive, and treat
  1271.              the character as default if so.  This is a hack.  */
  1272.           if ((symver_state != NULL) && (*symver_state == 0))
  1273.             goto de_fault;
  1274. #endif
  1275.  
  1276. #ifdef TC_ARM
  1277.           /* For the ARM, care is needed not to damage occurrences of \@
  1278.              by stripping the @ onwards.  Yuck.  */
  1279.           if (to > tostart && *(to - 1) == '\\')
  1280.             /* Do not treat the @ as a start-of-comment.  */
  1281.             goto de_fault;
  1282. #endif
  1283.  
  1284. #ifdef WARN_COMMENTS
  1285.           if (!found_comment)
  1286.             as_where (&found_comment_file, &found_comment);
  1287. #endif
  1288.           do
  1289.             {
  1290.               ch = GET ();
  1291.             }
  1292.           while (ch != EOF && !IS_NEWLINE (ch));
  1293.           if (ch == EOF)
  1294.             as_warn (_("end of file in comment; newline inserted"));
  1295.           state = 0;
  1296.           PUT ('\n');
  1297.           break;
  1298.  
  1299. #ifdef H_TICK_HEX
  1300.         case LEX_IS_H:
  1301.           /* Look for strings like H'[0-9A-Fa-f] and if found, replace
  1302.              the H' with 0x to make them gas-style hex characters.  */
  1303.           if (enable_h_tick_hex)
  1304.             {
  1305.               char quot;
  1306.  
  1307.               quot = GET ();
  1308.               if (quot == '\'')
  1309.                 {
  1310.                   UNGET ('x');
  1311.                   ch = '0';
  1312.                 }
  1313.               else
  1314.                 UNGET (quot);
  1315.             }
  1316.           /* FALL THROUGH */
  1317. #endif
  1318.  
  1319.         case LEX_IS_SYMBOL_COMPONENT:
  1320.           if (state == 10)
  1321.             {
  1322.               /* This is a symbol character following another symbol
  1323.                  character, with whitespace in between.  We skipped
  1324.                  the whitespace earlier, so output it now.  */
  1325.               UNGET (ch);
  1326.               state = 3;
  1327.               PUT (' ');
  1328.               break;
  1329.             }
  1330.  
  1331. #ifdef TC_Z80
  1332.           /* "af'" is a symbol containing '\''.  */
  1333.           if (state == 3 && (ch == 'a' || ch == 'A'))
  1334.             {
  1335.               state = 16;
  1336.               PUT (ch);
  1337.               ch = GET ();
  1338.               if (ch == 'f' || ch == 'F')
  1339.                 {
  1340.                   state = 17;
  1341.                   PUT (ch);
  1342.                   break;
  1343.                 }
  1344.               else
  1345.                 {
  1346.                   state = 9;
  1347.                   if (ch == EOF || !IS_SYMBOL_COMPONENT (ch))
  1348.                     {
  1349.                       if (ch != EOF)
  1350.                         UNGET (ch);
  1351.                       break;
  1352.                     }
  1353.                 }
  1354.             }
  1355. #endif
  1356.           if (state == 3)
  1357.             state = 9;
  1358.  
  1359.           /* This is a common case.  Quickly copy CH and all the
  1360.              following symbol component or normal characters.  */
  1361.           if (to + 1 < toend
  1362.               && mri_state == NULL
  1363. #if defined TC_ARM && defined OBJ_ELF
  1364.               && symver_state == NULL
  1365. #endif
  1366.               )
  1367.             {
  1368.               char *s;
  1369.               ptrdiff_t len;
  1370.  
  1371.               for (s = from; s < fromend; s++)
  1372.                 {
  1373.                   int type;
  1374.  
  1375.                   ch2 = *(unsigned char *) s;
  1376.                   type = lex[ch2];
  1377.                   if (type != 0
  1378.                       && type != LEX_IS_SYMBOL_COMPONENT)
  1379.                     break;
  1380.                 }
  1381.  
  1382.               if (s > from)
  1383.                 /* Handle the last character normally, for
  1384.                    simplicity.  */
  1385.                 --s;
  1386.  
  1387.               len = s - from;
  1388.  
  1389.               if (len > (toend - to) - 1)
  1390.                 len = (toend - to) - 1;
  1391.  
  1392.               if (len > 0)
  1393.                 {
  1394.                   PUT (ch);
  1395.                   memcpy (to, from, len);
  1396.                   to += len;
  1397.                   from += len;
  1398.                   if (to >= toend)
  1399.                     goto tofull;
  1400.                   ch = GET ();
  1401.                 }
  1402.             }
  1403.  
  1404.           /* Fall through.  */
  1405.         default:
  1406.         de_fault:
  1407.           /* Some relatively `normal' character.  */
  1408.           if (state == 0)
  1409.             {
  1410.               state = 11;       /* Now seeing label definition.  */
  1411.             }
  1412.           else if (state == 1)
  1413.             {
  1414.               state = 2;        /* Ditto.  */
  1415.             }
  1416.           else if (state == 9)
  1417.             {
  1418.               if (!IS_SYMBOL_COMPONENT (ch))
  1419.                 state = 3;
  1420.             }
  1421.           else if (state == 10)
  1422.             {
  1423.               if (ch == '\\')
  1424.                 {
  1425.                   /* Special handling for backslash: a backslash may
  1426.                      be the beginning of a formal parameter (of a
  1427.                      macro) following another symbol character, with
  1428.                      whitespace in between.  If that is the case, we
  1429.                      output a space before the parameter.  Strictly
  1430.                      speaking, correct handling depends upon what the
  1431.                      macro parameter expands into; if the parameter
  1432.                      expands into something which does not start with
  1433.                      an operand character, then we don't want to keep
  1434.                      the space.  We don't have enough information to
  1435.                      make the right choice, so here we are making the
  1436.                      choice which is more likely to be correct.  */
  1437.                   if (to + 1 >= toend)
  1438.                     {
  1439.                       /* If we're near the end of the buffer, save the
  1440.                          character for the next time round.  Otherwise
  1441.                          we'll lose our state.  */
  1442.                       UNGET (ch);
  1443.                       goto tofull;
  1444.                     }
  1445.                   *to++ = ' ';
  1446.                 }
  1447.  
  1448.               state = 3;
  1449.             }
  1450.           PUT (ch);
  1451.           break;
  1452.         }
  1453.     }
  1454.  
  1455.   /*NOTREACHED*/
  1456.  
  1457.  fromeof:
  1458.   /* We have reached the end of the input.  */
  1459.   return to - tostart;
  1460.  
  1461.  tofull:
  1462.   /* The output buffer is full.  Save any input we have not yet
  1463.      processed.  */
  1464.   if (fromend > from)
  1465.     {
  1466.       saved_input = from;
  1467.       saved_input_len = fromend - from;
  1468.     }
  1469.   else
  1470.     saved_input = NULL;
  1471.  
  1472.   return to - tostart;
  1473. }
  1474.