/* This is the Assembler Pre-Processor

   Copyright (C) 1987-2023 Free Software Foundation, Inc.

   This file is part of GAS, the GNU Assembler.

   GAS is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 3, or (at your option)

   any later version.

   GAS is distributed in the hope that it will be useful, but WITHOUT

   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY

   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public

   License for more details.

   You should have received a copy of the GNU General Public License

   along with GAS; see the file COPYING.  If not, write to the Free

   Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA

   02110-1301, USA.  */

/* Modified by Allen Wirfs-Brock, Instantiations Inc 2/90.  */

/* App, the assembler pre-processor.  This pre-processor strips out

   excess spaces, turns single-quoted characters into a decimal

   constant, and turns the # in # <number> <filename> <garbage> into a

   .linefile.  This needs better error-handling.  */

#include "as.h"

#if (__STDC__ != 1)

#ifndef const

#define const  /* empty */

#endif

#endif

#ifdef H_TICK_HEX

int enable_h_tick_hex = 0;

#endif

#ifdef TC_M68K

/* Whether we are scrubbing in m68k MRI mode.  This is different from

   flag_m68k_mri, because the two flags will be affected by the .mri

   pseudo-op at different times.  */

static int scrub_m68k_mri;

/* The pseudo-op which switches in and out of MRI mode.  See the

   comment in do_scrub_chars.  */

static const char mri_pseudo[] = ".mri 0";

#else

#define scrub_m68k_mri 0

#endif

#if defined TC_ARM && defined OBJ_ELF

/* The pseudo-op for which we need to special-case `@' characters.

   See the comment in do_scrub_chars.  */

static const char   symver_pseudo[] = ".symver";

static const char * symver_state;

#endif

static char last_char;

static char lex[256];

static const char symbol_chars[] =

"$._ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

#define LEX_IS_SYMBOL_COMPONENT   1

#define LEX_IS_WHITESPACE   2

#define LEX_IS_LINE_SEPARATOR   3

#define LEX_IS_COMMENT_START    4

#define LEX_IS_LINE_COMMENT_START 5

#define LEX_IS_TWOCHAR_COMMENT_1ST  6

#define LEX_IS_STRINGQUOTE    8

#define LEX_IS_COLON      9

#define LEX_IS_NEWLINE      10

#define LEX_IS_ONECHAR_QUOTE    11

#ifdef TC_V850

#define LEX_IS_DOUBLEDASH_1ST   12

#endif

#ifdef TC_M32R

#define DOUBLEBAR_PARALLEL

#endif

#ifdef DOUBLEBAR_PARALLEL

#define LEX_IS_DOUBLEBAR_1ST    13

#endif

#define LEX_IS_PARALLEL_SEPARATOR 14

#ifdef H_TICK_HEX

#define LEX_IS_H      15

#endif

#define IS_SYMBOL_COMPONENT(c)    (lex[c] == LEX_IS_SYMBOL_COMPONENT)

#define IS_WHITESPACE(c)    (lex[c] == LEX_IS_WHITESPACE)

#define IS_LINE_SEPARATOR(c)    (lex[c] == LEX_IS_LINE_SEPARATOR)

#define IS_PARALLEL_SEPARATOR(c)  (lex[c] == LEX_IS_PARALLEL_SEPARATOR)

#define IS_COMMENT(c)     (lex[c] == LEX_IS_COMMENT_START)

#define IS_LINE_COMMENT(c)    (lex[c] == LEX_IS_LINE_COMMENT_START)

#define IS_NEWLINE(c)     (lex[c] == LEX_IS_NEWLINE)

static int process_escape (int);

/* FIXME-soon: The entire lexer/parser thingy should be

   built statically at compile time rather than dynamically

   each and every time the assembler is run.  xoxorich.  */

void

do_scrub_begin (int m68k_mri ATTRIBUTE_UNUSED)

{

  const char *p;

  int c;

  lex[' '] = LEX_IS_WHITESPACE;

  lex['\t'] = LEX_IS_WHITESPACE;

  lex['\r'] = LEX_IS_WHITESPACE;

  lex['\n'] = LEX_IS_NEWLINE;

  lex[':'] = LEX_IS_COLON;

#ifdef TC_M68K

  scrub_m68k_mri = m68k_mri;

  if (! m68k_mri)

#endif

    {

      lex['"'] = LEX_IS_STRINGQUOTE;

#if ! defined (TC_HPPA)

      lex['\''] = LEX_IS_ONECHAR_QUOTE;

#endif

#ifdef SINGLE_QUOTE_STRINGS

      lex['\''] = LEX_IS_STRINGQUOTE;

#endif

    }

  /* Note: if any other character can be LEX_IS_STRINGQUOTE, the loop

     in state 5 of do_scrub_chars must be changed.  */

  /* Note that these override the previous defaults, e.g. if ';' is a

     comment char, then it isn't a line separator.  */

  for (p = symbol_chars; *p; ++p)

    lex[(unsigned char) *p] = LEX_IS_SYMBOL_COMPONENT;

  for (c = 128; c < 256; ++c)

    lex[c] = LEX_IS_SYMBOL_COMPONENT;

#ifdef tc_symbol_chars

  /* This macro permits the processor to specify all characters which

     may appears in an operand.  This will prevent the scrubber from

     discarding meaningful whitespace in certain cases.  The i386

     backend uses this to support prefixes, which can confuse the

     scrubber as to whether it is parsing operands or opcodes.  */

  for (p = tc_symbol_chars; *p; ++p)

    lex[(unsigned char) *p] = LEX_IS_SYMBOL_COMPONENT;

#endif

  /* The m68k backend wants to be able to change comment_chars.  */

#ifndef tc_comment_chars

#define tc_comment_chars comment_chars

#endif

  for (p = tc_comment_chars; *p; p++)

    lex[(unsigned char) *p] = LEX_IS_COMMENT_START;

  for (p = line_comment_chars; *p; p++)

    lex[(unsigned char) *p] = LEX_IS_LINE_COMMENT_START;

#ifndef tc_line_separator_chars

#define tc_line_separator_chars line_separator_chars

#endif

  for (p = tc_line_separator_chars; *p; p++)

    lex[(unsigned char) *p] = LEX_IS_LINE_SEPARATOR;

#ifdef tc_parallel_separator_chars

  /* This macro permits the processor to specify all characters which

     separate parallel insns on the same line.  */

  for (p = tc_parallel_separator_chars; *p; p++)

    lex[(unsigned char) *p] = LEX_IS_PARALLEL_SEPARATOR;

#endif

  /* Only allow slash-star comments if slash is not in use.

     FIXME: This isn't right.  We should always permit them.  */

  if (lex['/'] == 0)

    lex['/'] = LEX_IS_TWOCHAR_COMMENT_1ST;

#ifdef TC_M68K

  if (m68k_mri)

    {

      lex['\''] = LEX_IS_STRINGQUOTE;

      lex[';'] = LEX_IS_COMMENT_START;

      lex['*'] = LEX_IS_LINE_COMMENT_START;

      /* The MRI documentation says '!' is LEX_IS_COMMENT_START, but

   then it can't be used in an expression.  */

      lex['!'] = LEX_IS_LINE_COMMENT_START;

    }

#endif

#ifdef TC_V850

  lex['-'] = LEX_IS_DOUBLEDASH_1ST;

#endif

#ifdef DOUBLEBAR_PARALLEL

  lex['|'] = LEX_IS_DOUBLEBAR_1ST;

#endif

#ifdef TC_D30V

  /* Must do this is we want VLIW instruction with "->" or "<-".  */

  lex['-'] = LEX_IS_SYMBOL_COMPONENT;

#endif

#ifdef H_TICK_HEX

  if (enable_h_tick_hex)

    {

      lex['h'] = LEX_IS_H;

      lex['H'] = LEX_IS_H;

    }

#endif

}

/* Saved state of the scrubber.  */

static int state;

static int old_state;

static const char *out_string;

static char out_buf[20];

static int add_newlines;

static char *saved_input;

static size_t saved_input_len;

static char input_buffer[32 * 1024];

static const char *mri_state;

static char mri_last_ch;

/* Data structure for saving the state of app across #include's.  Note that

   app is called asynchronously to the parsing of the .include's, so our

   state at the time .include is interpreted is completely unrelated.

   That's why we have to save it all.  */

struct app_save

{

  int          state;

  int          old_state;

  const char * out_string;

  char         out_buf[sizeof (out_buf)];

  int          add_newlines;

  char *       saved_input;

  size_t       saved_input_len;

#ifdef TC_M68K

  int          scrub_m68k_mri;

#endif

  const char * mri_state;

  char         mri_last_ch;

#if defined TC_ARM && defined OBJ_ELF

  const char * symver_state;

#endif

  char         last_char;

};

char *

app_push (void)

{

  struct app_save *saved;

  saved = XNEW (struct app_save);

  saved->state = state;

  saved->old_state = old_state;

  saved->out_string = out_string;

  memcpy (saved->out_buf, out_buf, sizeof (out_buf));

  saved->add_newlines = add_newlines;

  if (saved_input == NULL)

    saved->saved_input = NULL;

  else

    {

      saved->saved_input = XNEWVEC (char, saved_input_len);

      memcpy (saved->saved_input, saved_input, saved_input_len);

      saved->saved_input_len = saved_input_len;

    }

#ifdef TC_M68K

  saved->scrub_m68k_mri = scrub_m68k_mri;

#endif

  saved->mri_state = mri_state;

  saved->mri_last_ch = mri_last_ch;

#if defined TC_ARM && defined OBJ_ELF

  saved->symver_state = symver_state;

#endif

  saved->last_char = last_char;

  /* do_scrub_begin() is not useful, just wastes time.  */

  state = 0;

  saved_input = NULL;

  add_newlines = 0;

  return (char *) saved;

}

void

app_pop (char *arg)

{

  struct app_save *saved = (struct app_save *) arg;

  /* There is no do_scrub_end ().  */

  state = saved->state;

  old_state = saved->old_state;

  out_string = saved->out_string;

  memcpy (out_buf, saved->out_buf, sizeof (out_buf));

  add_newlines = saved->add_newlines;

  if (saved->saved_input == NULL)

    saved_input = NULL;

  else

    {

      gas_assert (saved->saved_input_len <= sizeof (input_buffer));

      memcpy (input_buffer, saved->saved_input, saved->saved_input_len);

      saved_input = input_buffer;

      saved_input_len = saved->saved_input_len;

      free (saved->saved_input);

    }

#ifdef TC_M68K

  scrub_m68k_mri = saved->scrub_m68k_mri;

#endif

  mri_state = saved->mri_state;

  mri_last_ch = saved->mri_last_ch;

#if defined TC_ARM && defined OBJ_ELF

  symver_state = saved->symver_state;

#endif

  last_char = saved->last_char;

  free (arg);

}

/* @@ This assumes that \n &c are the same on host and target.  This is not

   necessarily true.  */

static int

process_escape (int ch)

{

  switch (ch)

    {

    case 'b':

      return '\b';

    case 'f':

      return '\f';

    case 'n':

      return '\n';

    case 'r':

      return '\r';

    case 't':

      return '\t';

    case '\'':

      return '\'';

    case '"':

      return '\"';

    default:

      return ch;

    }

}

#define MULTIBYTE_WARN_COUNT_LIMIT 10

static unsigned int multibyte_warn_count = 0;

bool

scan_for_multibyte_characters (const unsigned char *  start,

             const unsigned char *  end,

             bool                   warn)

{

  if (end <= start)

    return false;

  if (warn && multibyte_warn_count > MULTIBYTE_WARN_COUNT_LIMIT)

    return false;

  bool found = false;

  while (start < end)

    {

      unsigned char c;

      if ((c = * start++) <= 0x7f)

  continue;

      if (!warn)

  return true;

      found = true;

      const char * filename;

      unsigned int lineno;

      filename = as_where (& lineno);

      if (filename == NULL)

  as_warn (_("multibyte character (%#x) encountered in input"), c);

      else if (lineno == 0)

  as_warn (_("multibyte character (%#x) encountered in %s"), c, filename);

      else

  as_warn (_("multibyte character (%#x) encountered in %s at or near line %u"), c, filename, lineno);

      if (++ multibyte_warn_count == MULTIBYTE_WARN_COUNT_LIMIT)

  {

    as_warn (_("further multibyte character warnings suppressed"));

    break;

  }

    }

  return found;

}

/* This function is called to process input characters.  The GET

   parameter is used to retrieve more input characters.  GET should

   set its parameter to point to a buffer, and return the length of

   the buffer; it should return 0 at end of file.  The scrubbed output

   characters are put into the buffer starting at TOSTART; the TOSTART

   buffer is TOLEN bytes in length.  The function returns the number

   of scrubbed characters put into TOSTART.  This will be TOLEN unless

   end of file was seen.  This function is arranged as a state

   machine, and saves its state so that it may return at any point.

   This is the way the old code used to work.  */

size_t

do_scrub_chars (size_t (*get) (char *, size_t), char *tostart, size_t tolen)

{

  char *to = tostart;

  char *toend = tostart + tolen;

  char *from;

  char *fromend;

  size_t fromlen;

  int ch, ch2 = 0;

  /* Character that started the string we're working on.  */

  static char quotechar;

  /*State 0: beginning of normal line

    1: After first whitespace on line (flush more white)

    2: After first non-white (opcode) on line (keep 1white)

    3: after second white on line (into operands) (flush white)

    4: after putting out a .linefile, put out digits

    5: parsing a string, then go to old-state

    6: putting out \ escape in a "d string.

    7: no longer used

    8: no longer used

    9: After seeing symbol char in state 3 (keep 1white after symchar)

   10: After seeing whitespace in state 9 (keep white before symchar)

   11: After seeing a symbol character in state 0 (eg a label definition)

   -1: output string in out_string and go to the state in old_state

   -2: flush text until a '*' '/' is seen, then go to state old_state

#ifdef TC_V850

   12: After seeing a dash, looking for a second dash as a start

       of comment.

#endif

#ifdef DOUBLEBAR_PARALLEL

   13: After seeing a vertical bar, looking for a second

       vertical bar as a parallel expression separator.

#endif

#ifdef TC_PREDICATE_START_CHAR

   14: After seeing a predicate start character at state 0, looking

       for a predicate end character as predicate.

   15: After seeing a predicate start character at state 1, looking

       for a predicate end character as predicate.

#endif

#ifdef TC_Z80

   16: After seeing an 'a' or an 'A' at the start of a symbol

   17: After seeing an 'f' or an 'F' in state 16

#endif

    */

  /* I added states 9 and 10 because the MIPS ECOFF assembler uses

     constructs like ``.loc 1 20''.  This was turning into ``.loc

     120''.  States 9 and 10 ensure that a space is never dropped in

     between characters which could appear in an identifier.  Ian

     Taylor, ian@cygnus.com.

     I added state 11 so that something like "Lfoo add %r25,%r26,%r27" works

     correctly on the PA (and any other target where colons are optional).

     Jeff Law, law@cs.utah.edu.

     I added state 13 so that something like "cmp r1, r2 || trap #1" does not

     get squashed into "cmp r1,r2||trap#1", with the all important space

     between the 'trap' and the '#1' being eliminated.  nickc@cygnus.com  */

  /* This macro gets the next input character.  */

#define GET()             \

  (from < fromend            \

   ? * (unsigned char *) (from++)        \

   : (saved_input = NULL,          \

      fromlen = (*get) (input_buffer, sizeof input_buffer), \

      from = input_buffer,          \

      fromend = from + fromlen,         \

      (fromlen == 0            \

       ? EOF              \

       : * (unsigned char *) (from++))))

  /* This macro pushes a character back on the input stream.  */

#define UNGET(uch) (*--from = (uch))

  /* This macro puts a character into the output buffer.  If this

     character fills the output buffer, this macro jumps to the label

     TOFULL.  We use this rather ugly approach because we need to

     handle two different termination conditions: EOF on the input

     stream, and a full output buffer.  It would be simpler if we

     always read in the entire input stream before processing it, but

     I don't want to make such a significant change to the assembler's

     memory usage.  */

#define PUT(pch)        \

  do            \

    {           \

      *to++ = (pch);        \

      if (to >= toend)       \

  goto tofull;       \

    }           \

  while (0)

  if (saved_input != NULL)

    {

      from = saved_input;

      fromend = from + saved_input_len;

    }

  else

    {

      fromlen = (*get) (input_buffer, sizeof input_buffer);

      if (fromlen == 0)

  return 0;

      from = input_buffer;

      fromend = from + fromlen;

      if (multibyte_handling == multibyte_warn)

  (void) scan_for_multibyte_characters ((const unsigned char *) from,

                (const unsigned char* ) fromend,

                true /* Generate warnings.  */);

    }

  while (1)

    {

      /* The cases in this switch end with continue, in order to

   branch back to the top of this while loop and generate the

   next output character in the appropriate state.  */

      switch (state)

  {

  case -1:

    ch = *out_string++;

    if (*out_string == '\0')

      {

        state = old_state;

        old_state = 3;

      }

    PUT (ch);

    continue;

  case -2:

    for (;;)

      {

        do

    {

      ch = GET ();

      if (ch == EOF)

        {

          as_warn (_("end of file in comment"));

          goto fromeof;

        }

      if (ch == '\n')

        PUT ('\n');

    }

        while (ch != '*');

        while ((ch = GET ()) == '*')

    ;

        if (ch == EOF)

    {

      as_warn (_("end of file in comment"));

      goto fromeof;

    }

        if (ch == '/')

    break;

        UNGET (ch);

      }

    state = old_state;

    UNGET (' ');

    continue;

  case 4:

    ch = GET ();

    if (ch == EOF)

      goto fromeof;

    else if (ch >= '0' && ch <= '9')

      PUT (ch);

    else

      {

        while (ch != EOF && IS_WHITESPACE (ch))

    ch = GET ();

        if (ch == '"')

    {

      quotechar = ch;

      state = 5;

      old_state = 3;

      PUT (ch);

    }

        else

    {

      while (ch != EOF && ch != '\n')

        ch = GET ();

      state = 0;

      PUT (ch);

    }

      }

    continue;

  case 5:

    /* We are going to copy everything up to a quote character,

       with special handling for a backslash.  We try to

       optimize the copying in the simple case without using the

       GET and PUT macros.  */

    {

      char *s;

      ptrdiff_t len;

      for (s = from; s < fromend; s++)

        {

    ch = *s;

    if (ch == '\\'

        || ch == quotechar

        || ch == '\n')

      break;

        }

      len = s - from;

      if (len > toend - to)

        len = toend - to;

      if (len > 0)

        {

    memcpy (to, from, len);

    to += len;

    from += len;

    if (to >= toend)

      goto tofull;

        }

    }

    ch = GET ();

    if (ch == EOF)

      {

        /* This buffer is here specifically so

     that the UNGET below will work.  */

        static char one_char_buf[1];

        as_warn (_("end of file in string; '%c' inserted"), quotechar);

        state = old_state;

        from = fromend = one_char_buf + 1;

        fromlen = 1;

        UNGET ('\n');

        PUT (quotechar);

      }

    else if (ch == quotechar)

      {

        state = old_state;

        PUT (ch);

      }

    else if (TC_STRING_ESCAPES && ch == '\\')

      {

        state = 6;

        PUT (ch);

      }

    else if (scrub_m68k_mri && ch == '\n')

      {

        /* Just quietly terminate the string.  This permits lines like

       bne  label loop if we haven't reach end yet.  */

        state = old_state;

        UNGET (ch);

        PUT ('\'');

      }

    else

      {

        PUT (ch);

      }

    continue;

  case 6:

    state = 5;

    ch = GET ();

    switch (ch)

      {

        /* Handle strings broken across lines, by turning '\n' into

     '\\' and 'n'.  */

      case '\n':

        UNGET ('n');

        add_newlines++;

        PUT ('\\');

        continue;

      case EOF:

        as_warn (_("end of file in string; '%c' inserted"), quotechar);

        PUT (quotechar);

        continue;

      case '"':

      case '\\':

      case 'b':

      case 'f':

      case 'n':

      case 'r':

      case 't':

      case 'v':

      case 'x':

      case 'X':

      case '0':

      case '1':

      case '2':

      case '3':

      case '4':

      case '5':

      case '6':

      case '7':

        break;

      default:

#ifdef ONLY_STANDARD_ESCAPES

        as_warn (_("unknown escape '\\%c' in string; ignored"), ch);

#endif

        break;

      }

    PUT (ch);

    continue;

#ifdef DOUBLEBAR_PARALLEL

  case 13:

    ch = GET ();

    if (ch != '|')

      abort ();

    /* Reset back to state 1 and pretend that we are parsing a

       line from just after the first white space.  */

    state = 1;

    PUT ('|');

#ifdef TC_TIC6X

    /* "||^" is used for SPMASKed instructions.  */

    ch = GET ();

    if (ch == EOF)

      goto fromeof;

    else if (ch == '^')

      PUT ('^');

    else

      UNGET (ch);

#endif

    continue;

#endif

#ifdef TC_Z80

  case 16:

    /* We have seen an 'a' at the start of a symbol, look for an 'f'.  */

    ch = GET ();

    if (ch == 'f' || ch == 'F')

      {

        state = 17;

        PUT (ch);

      }

    else

      {

        if (ch != EOF)

    UNGET (ch);

        state = 9;

        break;

      }

    /* Fall through.  */

  case 17:

    /* We have seen "af" at the start of a symbol,

       a ' here is a part of that symbol.  */

    ch = GET ();

    state = 9;

    if (ch == '\'')

      /* Change to avoid warning about unclosed string.  */

      PUT ('`');

    else if (ch != EOF)

      UNGET (ch);

    break;

#endif

  }

      /* OK, we are somewhere in states 0 through 4 or 9 through 11.  */

      /* flushchar: */

      ch = GET ();

#ifdef TC_PREDICATE_START_CHAR

      if (ch == TC_PREDICATE_START_CHAR && (state == 0 || state == 1))

  {

    state += 14;

    PUT (ch);

    continue;

  }

      else if (state == 14 || state == 15)

  {

    if (ch == TC_PREDICATE_END_CHAR)

      {

        state -= 14;

        PUT (ch);

        ch = GET ();

      }

    else

      {

        PUT (ch);

        continue;

      }

  }

#endif

    recycle:

#if defined TC_ARM && defined OBJ_ELF

      /* We need to watch out for .symver directives.  See the comment later

   in this function.  */

      if (symver_state == NULL)

  {

    if ((state == 0 || state == 1) && ch == symver_pseudo[0])

      symver_state = symver_pseudo + 1;

  }

      else

  {

    /* We advance to the next state if we find the right

       character.  */

    if (ch != '\0' && (*symver_state == ch))

      ++symver_state;

    else if (*symver_state != '\0')

      /* We did not get the expected character, or we didn't

         get a valid terminating character after seeing the

         entire pseudo-op, so we must go back to the beginning.  */

      symver_state = NULL;

    else

      {

        /* We've read the entire pseudo-op.  If this is the end

     of the line, go back to the beginning.  */

        if (IS_NEWLINE (ch))

    symver_state = NULL;

      }

  }

#endif /* TC_ARM && OBJ_ELF */

#ifdef TC_M68K

      /* We want to have pseudo-ops which control whether we are in

   MRI mode or not.  Unfortunately, since m68k MRI mode affects

   the scrubber, that means that we need a special purpose

   recognizer here.  */

      if (mri_state == NULL)

  {

    if ((state == 0 || state == 1)

        && ch == mri_pseudo[0])

      mri_state = mri_pseudo + 1;

  }

      else

  {

    /* We advance to the next state if we find the right

       character, or if we need a space character and we get any

       whitespace character, or if we need a '0' and we get a

       '1' (this is so that we only need one state to handle

       ``.mri 0'' and ``.mri 1'').  */

    if (ch != '\0'

        && (*mri_state == ch

      || (*mri_state == ' '

          && lex[ch] == LEX_IS_WHITESPACE)

      || (*mri_state == '0'

          && ch == '1')))

      {

        mri_last_ch = ch;

        ++mri_state;

      }

    else if (*mri_state != '\0'

       || (lex[ch] != LEX_IS_WHITESPACE

           && lex[ch] != LEX_IS_NEWLINE))

      {

        /* We did not get the expected character, or we didn't

     get a valid terminating character after seeing the

     entire pseudo-op, so we must go back to the

     beginning.  */

        mri_state = NULL;

      }

    else

      {

        /* We've read the entire pseudo-op.  mips_last_ch is

     either '0' or '1' indicating whether to enter or

     leave MRI mode.  */

        do_scrub_begin (mri_last_ch == '1');

        mri_state = NULL;

        /* We continue handling the character as usual.  The

     main gas reader must also handle the .mri pseudo-op

     to control expression parsing and the like.  */

      }

  }

#endif

      if (ch == EOF)

  {

    if (state != 0)

      {

        as_warn (_("end of file not at end of a line; newline inserted"));

        state = 0;

        PUT ('\n');

      }

    goto fromeof;

  }

      switch (lex[ch])

  {

  case LEX_IS_WHITESPACE:

    do

      {

        ch = GET ();

      }

    while (ch != EOF && IS_WHITESPACE (ch));

    if (ch == EOF)

      goto fromeof;

    if (state == 0)

      {

        /* Preserve a single whitespace character at the

     beginning of a line.  */

        state = 1;

        UNGET (ch);

        PUT (' ');

        break;

      }

#ifdef KEEP_WHITE_AROUND_COLON

    if (lex[ch] == LEX_IS_COLON)

      {

        /* Only keep this white if there's no white *after* the

     colon.  */

        ch2 = GET ();

        if (ch2 != EOF)

    UNGET (ch2);

        if (!IS_WHITESPACE (ch2))

    {

      state = 9;

      UNGET (ch);

      PUT (' ');

      break;

    }

      }

#endif

    if (IS_COMMENT (ch)

        || IS_LINE_SEPARATOR (ch)

        || IS_PARALLEL_SEPARATOR (ch))

      {

        if (scrub_m68k_mri)

    {

      /* In MRI mode, we keep these spaces.  */

      UNGET (ch);

      PUT (' ');

      break;

    }

        goto recycle;

      }

    /* If we're in state 2 or 11, we've seen a non-white

       character followed by whitespace.  If the next character

       is ':', this is whitespace after a label name which we

       normally must ignore.  In MRI mode, though, spaces are

       not permitted between the label and the colon.  */

    if ((state == 2 || state == 11)

        && lex[ch] == LEX_IS_COLON

        && ! scrub_m68k_mri)

      {

        state = 1;

        PUT (ch);

        break;

      }

    switch (state)

      {

      case 1:

        /* We can arrive here if we leave a leading whitespace

     character at the beginning of a line.  */

        goto recycle;

      case 2:

        state = 3;

        if (to + 1 < toend)

    {

      /* Optimize common case by skipping UNGET/GET.  */

      PUT (' '); /* Sp after opco */

      goto recycle;

    }

        UNGET (ch);

        PUT (' ');

        break;

      case 3:

#ifndef TC_KEEP_OPERAND_SPACES

        /* For TI C6X, we keep these spaces as they may separate

     functional unit specifiers from operands.  */

        if (scrub_m68k_mri)

#endif

    {

      /* In MRI mode, we keep these spaces.  */

      UNGET (ch);

      PUT (' ');

      break;

    }

        goto recycle; /* Sp in operands */

      case 9:

      case 10:

#ifndef TC_KEEP_OPERAND_SPACES

        if (scrub_m68k_mri)

#endif

    {

      /* In MRI mode, we keep these spaces.  */

      state = 3;

      UNGET (ch);

      PUT (' ');

      break;

    }

        state = 10; /* Sp after symbol char */

        goto recycle;

      case 11:

        if (LABELS_WITHOUT_COLONS || flag_m68k_mri)

    state = 1;

        else

    {

      /* We know that ch is not ':', since we tested that

         case above.  Therefore this is not a label, so it

         must be the opcode, and we've just seen the

         whitespace after it.  */

      state = 3;

    }

        UNGET (ch);

        PUT (' '); /* Sp after label definition.  */

        break;

      default:

        BAD_CASE (state);

      }

    break;

  case LEX_IS_TWOCHAR_COMMENT_1ST:

    ch2 = GET ();

    if (ch2 == '*')

      {

        for (;;)

    {

      do

        {

          ch2 = GET ();

          if (ch2 != EOF && IS_NEWLINE (ch2))

      add_newlines++;

        }

      while (ch2 != EOF && ch2 != '*');

      while (ch2 == '*')

        ch2 = GET ();

      if (ch2 == EOF || ch2 == '/')

        break;

      /* This UNGET will ensure that we count newlines

         correctly.  */