[binutils.git] / gas / cond.c

/* cond.c - conditional assembly pseudo-ops, and .include
   Copyright 1990, 1991, 1992, 1993, 1995, 1997, 1998, 2000, 2001
   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 2, 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, 59 Temple Place - Suite 330, Boston, MA
   02111-1307, USA.  */

#include "as.h"
#include "macro.h"

#include "obstack.h"

/* This is allocated to grow and shrink as .ifdef/.endif pairs are
   scanned.  */
struct obstack cond_obstack;

struct file_line {
  char *file;
  unsigned int line;
};

/* We push one of these structures for each .if, and pop it at the
   .endif.  */

struct conditional_frame {
  /* The source file & line number of the "if".  */
  struct file_line if_file_line;
  /* The source file & line of the "else".  */
  struct file_line else_file_line;
  /* The previous conditional.  */
  struct conditional_frame *previous_cframe;
  /* Have we seen an else yet?  */
  int else_seen;
  /* Whether we are currently ignoring input.  */
  int ignoring;
  /* Whether a conditional at a higher level is ignoring input.
     Set also when a branch of an "if .. elseif .." tree has matched
     to prevent further matches.  */
  int dead_tree;
  /* Macro nesting level at which this conditional was created.  */
  int macro_nest;
};

static void initialize_cframe PARAMS ((struct conditional_frame *cframe));
static char *get_mri_string PARAMS ((int, int *));

static struct conditional_frame *current_cframe = NULL;

/* Performs the .ifdef (test_defined == 1) and
   the .ifndef (test_defined == 0) pseudo op.  */

void
s_ifdef (test_defined)
     int test_defined;
{
  /* Points to name of symbol.  */
  char *name;
  /* Points to symbol.  */
  symbolS *symbolP;
  struct conditional_frame cframe;
  char c;

  /* Leading whitespace is part of operand.  */
  SKIP_WHITESPACE ();
  name = input_line_pointer;

  if (!is_name_beginner (*name))
    {
      as_bad (_("invalid identifier for \".ifdef\""));
      obstack_1grow (&cond_obstack, 0);
      ignore_rest_of_line ();
      return;
    }

  c = get_symbol_end ();
  symbolP = symbol_find (name);
  *input_line_pointer = c;

  initialize_cframe (&cframe);
  
  if (cframe.dead_tree)
    cframe.ignoring = 1;
  else
    {
      int is_defined;

      /* Use the same definition of 'defined' as .equiv so that a symbol
	 which has been referenced but not yet given a value/address is
	 considered to be undefined.  */
      is_defined =
	symbolP != NULL
	&& S_IS_DEFINED (symbolP)
	&& S_GET_SEGMENT (symbolP) != reg_section;

      cframe.ignoring = ! (test_defined ^ is_defined);
    }

  current_cframe = ((struct conditional_frame *)
		    obstack_copy (&cond_obstack, &cframe,
				  sizeof (cframe)));

  if (LISTING_SKIP_COND ()
      && cframe.ignoring
      && (cframe.previous_cframe == NULL
	  || ! cframe.previous_cframe->ignoring))
    listing_list (2);

  demand_empty_rest_of_line ();
}

void
s_if (arg)
     int arg;
{
  expressionS operand;
  struct conditional_frame cframe;
  int t;
  char *stop = NULL;
  char stopc;

  if (flag_mri)
    stop = mri_comment_field (&stopc);

  /* Leading whitespace is part of operand.  */
  SKIP_WHITESPACE ();

  if (current_cframe != NULL && current_cframe->ignoring)
    {
      operand.X_add_number = 0;
      while (! is_end_of_line[(unsigned char) *input_line_pointer])
	++input_line_pointer;
    }
  else
    {
      expression (&operand);
      if (operand.X_op != O_constant)
	as_bad (_("non-constant expression in \".if\" statement"));
    }

  switch ((operatorT) arg)
    {
    case O_eq: t = operand.X_add_number == 0; break;
    case O_ne: t = operand.X_add_number != 0; break;
    case O_lt: t = operand.X_add_number < 0; break;
    case O_le: t = operand.X_add_number <= 0; break;
    case O_ge: t = operand.X_add_number >= 0; break;
    case O_gt: t = operand.X_add_number > 0; break;
    default:
      abort ();
      return;
    }

  /* If the above error is signaled, this will dispatch
     using an undefined result.  No big deal.  */
  initialize_cframe (&cframe);
  cframe.ignoring = cframe.dead_tree || ! t;
  current_cframe = ((struct conditional_frame *)
		    obstack_copy (&cond_obstack, &cframe, sizeof (cframe)));

  if (LISTING_SKIP_COND ()
      && cframe.ignoring
      && (cframe.previous_cframe == NULL
	  || ! cframe.previous_cframe->ignoring))
    listing_list (2);

  if (flag_mri)
    mri_comment_end (stop, stopc);

  demand_empty_rest_of_line ();
}

/* Get a string for the MRI IFC or IFNC pseudo-ops.  */

static char *
get_mri_string (terminator, len)
     int terminator;
     int *len;
{
  char *ret;
  char *s;

  SKIP_WHITESPACE ();
  s = ret = input_line_pointer;
  if (*input_line_pointer == '\'')
    {
      ++s;
      ++input_line_pointer;
      while (! is_end_of_line[(unsigned char) *input_line_pointer])
	{
	  *s++ = *input_line_pointer++;
	  if (s[-1] == '\'')
	    {
	      if (*input_line_pointer != '\'')
		break;
	      ++input_line_pointer;
	    }
	}
      SKIP_WHITESPACE ();
    }
  else
    {
      while (*input_line_pointer != terminator
	     && ! is_end_of_line[(unsigned char) *input_line_pointer])
	++input_line_pointer;
      s = input_line_pointer;
      while (s > ret && (s[-1] == ' ' || s[-1] == '\t'))
	--s;
    }

  *len = s - ret;
  return ret;
}

/* The MRI IFC and IFNC pseudo-ops.  */

void
s_ifc (arg)
     int arg;
{
  char *stop = NULL;
  char stopc;
  char *s1, *s2;
  int len1, len2;
  int res;
  struct conditional_frame cframe;

  if (flag_mri)
    stop = mri_comment_field (&stopc);

  s1 = get_mri_string (',', &len1);

  if (*input_line_pointer != ',')
    as_bad (_("bad format for ifc or ifnc"));
  else
    ++input_line_pointer;

  s2 = get_mri_string (';', &len2);

  res = len1 == len2 && strncmp (s1, s2, len1) == 0;

  initialize_cframe (&cframe);
  cframe.ignoring = cframe.dead_tree || ! (res ^ arg);
  current_cframe = ((struct conditional_frame *)
		    obstack_copy (&cond_obstack, &cframe, sizeof (cframe)));

  if (LISTING_SKIP_COND ()
      && cframe.ignoring
      && (cframe.previous_cframe == NULL
	  || ! cframe.previous_cframe->ignoring))
    listing_list (2);

  if (flag_mri)
    mri_comment_end (stop, stopc);

  demand_empty_rest_of_line ();
}

void
s_elseif (arg)
     int arg;
{
  if (current_cframe == NULL)
    {
      as_bad (_("\".elseif\" without matching \".if\""));
    }
  else if (current_cframe->else_seen)
    {
      as_bad (_("\".elseif\" after \".else\""));
      as_bad_where (current_cframe->else_file_line.file,
		    current_cframe->else_file_line.line,
		    _("here is the previous \"else\""));
      as_bad_where (current_cframe->if_file_line.file,
		    current_cframe->if_file_line.line,
		    _("here is the previous \"if\""));
    }
  else
    {
      as_where (&current_cframe->else_file_line.file,
		&current_cframe->else_file_line.line);

      current_cframe->dead_tree |= !current_cframe->ignoring;
      current_cframe->ignoring = current_cframe->dead_tree;
    }

  if (current_cframe == NULL || current_cframe->ignoring)
    {
      while (! is_end_of_line[(unsigned char) *input_line_pointer])
	++input_line_pointer;

      if (current_cframe == NULL)
	return;
    }
  else
    {
      expressionS operand;
      int t;

      /* Leading whitespace is part of operand.  */
      SKIP_WHITESPACE ();

      expression (&operand);
      if (operand.X_op != O_constant)
	as_bad (_("non-constant expression in \".elseif\" statement"));

      switch ((operatorT) arg)
	{
	case O_eq: t = operand.X_add_number == 0; break;
	case O_ne: t = operand.X_add_number != 0; break;
	case O_lt: t = operand.X_add_number < 0; break;
	case O_le: t = operand.X_add_number <= 0; break;
	case O_ge: t = operand.X_add_number >= 0; break;
	case O_gt: t = operand.X_add_number > 0; break;
	default:
	  abort ();
	  return;
	}

      current_cframe->ignoring = current_cframe->dead_tree || ! t;
    }

  if (LISTING_SKIP_COND ()
      && (current_cframe->previous_cframe == NULL
	  || ! current_cframe->previous_cframe->ignoring))
    {
      if (! current_cframe->ignoring)
	listing_list (1);
      else
	listing_list (2);
    }

  demand_empty_rest_of_line ();
}

void
s_endif (arg)
     int arg ATTRIBUTE_UNUSED;
{
  struct conditional_frame *hold;

  if (current_cframe == NULL)
    {
      as_bad (_("\".endif\" without \".if\""));
    }
  else
    {
      if (LISTING_SKIP_COND ()
	  && current_cframe->ignoring
	  && (current_cframe->previous_cframe == NULL
	      || ! current_cframe->previous_cframe->ignoring))
	listing_list (1);

      hold = current_cframe;
      current_cframe = current_cframe->previous_cframe;
      obstack_free (&cond_obstack, hold);
    }				/* if one pop too many */

  if (flag_mri)
    {
      while (! is_end_of_line[(unsigned char) *input_line_pointer])
	++input_line_pointer;
    }

  demand_empty_rest_of_line ();
}

void
s_else (arg)
     int arg ATTRIBUTE_UNUSED;
{
  if (current_cframe == NULL)
    {
      as_bad (_("\".else\" without matching \".if\""));
    }
  else if (current_cframe->else_seen)
    {
      as_bad (_("duplicate \"else\""));
      as_bad_where (current_cframe->else_file_line.file,
		    current_cframe->else_file_line.line,
		    _("here is the previous \"else\""));
      as_bad_where (current_cframe->if_file_line.file,
		    current_cframe->if_file_line.line,
		    _("here is the previous \"if\""));
    }
  else
    {
      as_where (&current_cframe->else_file_line.file,
		&current_cframe->else_file_line.line);

      current_cframe->ignoring =
	current_cframe->dead_tree | !current_cframe->ignoring;

      if (LISTING_SKIP_COND ()
	  && (current_cframe->previous_cframe == NULL
	      || ! current_cframe->previous_cframe->ignoring))
	{
	  if (! current_cframe->ignoring)
	    listing_list (1);
	  else
	    listing_list (2);
	}

      current_cframe->else_seen = 1;
    }

  if (flag_mri)
    {
      while (! is_end_of_line[(unsigned char) *input_line_pointer])
	++input_line_pointer;
    }

  demand_empty_rest_of_line ();
}

void
s_ifeqs (arg)
     int arg;
{
  char *s1, *s2;
  int len1, len2;
  int res;
  struct conditional_frame cframe;

  s1 = demand_copy_C_string (&len1);

  SKIP_WHITESPACE ();
  if (*input_line_pointer != ',')
    {
      as_bad (_(".ifeqs syntax error"));
      ignore_rest_of_line ();
      return;
    }

  ++input_line_pointer;

  s2 = demand_copy_C_string (&len2);

  res = len1 == len2 && strncmp (s1, s2, len1) == 0;

  initialize_cframe (&cframe);
  cframe.ignoring = cframe.dead_tree || ! (res ^ arg);
  current_cframe = ((struct conditional_frame *)
		    obstack_copy (&cond_obstack, &cframe, sizeof (cframe)));

  if (LISTING_SKIP_COND ()
      && cframe.ignoring
      && (cframe.previous_cframe == NULL
	  || ! cframe.previous_cframe->ignoring))
    listing_list (2);

  demand_empty_rest_of_line ();
}

int
ignore_input ()
{
  char *s;

  s = input_line_pointer;

  if (NO_PSEUDO_DOT || flag_m68k_mri)
    {
      if (s[-1] != '.')
	--s;
    }
  else
    {
      if (s[-1] != '.')
	return (current_cframe != NULL) && (current_cframe->ignoring);
    }

  /* We cannot ignore certain pseudo ops.  */
  if (((s[0] == 'i'
	|| s[0] == 'I')
       && (!strncasecmp (s, "if", 2)
	   || !strncasecmp (s, "ifdef", 5)
	   || !strncasecmp (s, "ifndef", 6)))
      || ((s[0] == 'e'
	   || s[0] == 'E')
	  && (!strncasecmp (s, "else", 4)
	      || !strncasecmp (s, "endif", 5)
	      || !strncasecmp (s, "endc", 4))))
    return 0;

  return (current_cframe != NULL) && (current_cframe->ignoring);
}

static void
initialize_cframe (cframe)
     struct conditional_frame *cframe;
{
  memset (cframe, 0, sizeof (*cframe));
  as_where (&cframe->if_file_line.file,
	    &cframe->if_file_line.line);
  cframe->previous_cframe = current_cframe;
  cframe->dead_tree = current_cframe != NULL && current_cframe->ignoring;
  cframe->macro_nest = macro_nest;
}

/* Give an error if a conditional is unterminated inside a macro or
   the assembly as a whole.  If NEST is non negative, we are being
   called because of the end of a macro expansion.  If NEST is
   negative, we are being called at the of the input files.  */

void
cond_finish_check (nest)
     int nest;
{
  if (current_cframe != NULL && current_cframe->macro_nest >= nest)
    {
      if (nest >= 0)
	as_bad (_("end of macro inside conditional"));
      else
	as_bad (_("end of file inside conditional"));
      as_bad_where (current_cframe->if_file_line.file,
		    current_cframe->if_file_line.line,
		    _("here is the start of the unterminated conditional"));
      if (current_cframe->else_seen)
	as_bad_where (current_cframe->else_file_line.file,
		      current_cframe->else_file_line.line,
		      _("here is the \"else\" of the unterminated conditional"));
    }
}

/* This function is called when we exit out of a macro.  We assume
   that any conditionals which began within the macro are correctly
   nested, and just pop them off the stack.  */

void
cond_exit_macro (nest)
     int nest;
{
  while (current_cframe != NULL && current_cframe->macro_nest >= nest)
    {
      struct conditional_frame *hold;

      hold = current_cframe;
      current_cframe = current_cframe->previous_cframe;
      obstack_free (&cond_obstack, hold);
    }
}
Commit	Line	Data
252b5132	1	/* cond.c - conditional assembly pseudo-ops, and .include
cdbc6895	2	Copyright 1990, 1991, 1992, 1993, 1995, 1997, 1998, 2000, 2001
252b5132 RH	3	Free Software Foundation, Inc.
	4
	5	This file is part of GAS, the GNU Assembler.
	6
	7	GAS is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License as published by
	9	the Free Software Foundation; either version 2, or (at your option)
	10	any later version.
	11
	12	GAS is distributed in the hope that it will be useful,
	13	but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	GNU General Public License for more details.
	16
	17	You should have received a copy of the GNU General Public License
	18	along with GAS; see the file COPYING. If not, write to the Free
	19	Software Foundation, 59 Temple Place - Suite 330, Boston, MA
	20	02111-1307, USA. */
	21
	22	#include "as.h"
	23	#include "macro.h"
	24
	25	#include "obstack.h"
	26
76b0a8c0 KH	27	/* This is allocated to grow and shrink as .ifdef/.endif pairs are
76b0a8c0 KH	28	scanned. */
252b5132 RH	29	struct obstack cond_obstack;
252b5132 RH	30
30a2b4ef	31	struct file_line {
252b5132 RH	32	char *file;
	33	unsigned int line;
	34	};
	35
	36	/* We push one of these structures for each .if, and pop it at the
	37	.endif. */
	38
30a2b4ef	39	struct conditional_frame {
252b5132 RH	40	/* The source file & line number of the "if". */
	41	struct file_line if_file_line;
	42	/* The source file & line of the "else". */
	43	struct file_line else_file_line;
	44	/* The previous conditional. */
	45	struct conditional_frame *previous_cframe;
	46	/* Have we seen an else yet? */
	47	int else_seen;
	48	/* Whether we are currently ignoring input. */
	49	int ignoring;
cdbc6895 AM	50	/* Whether a conditional at a higher level is ignoring input.
	51	Set also when a branch of an "if .. elseif .." tree has matched
	52	to prevent further matches. */
252b5132 RH	53	int dead_tree;
	54	/* Macro nesting level at which this conditional was created. */
	55	int macro_nest;
	56	};
	57
	58	static void initialize_cframe PARAMS ((struct conditional_frame *cframe));
	59	static char get_mri_string PARAMS ((int, int ));
	60
	61	static struct conditional_frame *current_cframe = NULL;
	62
8dfa0188 NC	63	/* Performs the .ifdef (test_defined == 1) and
	64	the .ifndef (test_defined == 0) pseudo op. */
	65
76b0a8c0	66	void
8dfa0188 NC	67	s_ifdef (test_defined)
8dfa0188 NC	68	int test_defined;
252b5132	69	{
76b0a8c0	70	/* Points to name of symbol. */
8dfa0188	71	char *name;
76b0a8c0	72	/* Points to symbol. */
8dfa0188	73	symbolS *symbolP;
252b5132	74	struct conditional_frame cframe;
8dfa0188	75	char c;
252b5132	76
76b0a8c0 KH	77	/* Leading whitespace is part of operand. */
76b0a8c0 KH	78	SKIP_WHITESPACE ();
252b5132 RH	79	name = input_line_pointer;
	80
	81	if (!is_name_beginner (*name))
	82	{
	83	as_bad (_("invalid identifier for \".ifdef\""));
	84	obstack_1grow (&cond_obstack, 0);
	85	ignore_rest_of_line ();
8dfa0188	86	return;
252b5132	87	}
8dfa0188 NC	88
	89	c = get_symbol_end ();
	90	symbolP = symbol_find (name);
	91	*input_line_pointer = c;
	92
	93	initialize_cframe (&cframe);
	94
	95	if (cframe.dead_tree)
	96	cframe.ignoring = 1;
252b5132 RH	97	else
252b5132 RH	98	{
8dfa0188 NC	99	int is_defined;
	100
	101	/* Use the same definition of 'defined' as .equiv so that a symbol
	102	which has been referenced but not yet given a value/address is
	103	considered to be undefined. */
	104	is_defined =
	105	symbolP != NULL
	106	&& S_IS_DEFINED (symbolP)
	107	&& S_GET_SEGMENT (symbolP) != reg_section;
	108
	109	cframe.ignoring = ! (test_defined ^ is_defined);
	110	}
	111
	112	current_cframe = ((struct conditional_frame *)
	113	obstack_copy (&cond_obstack, &cframe,
	114	sizeof (cframe)));
	115
	116	if (LISTING_SKIP_COND ()
	117	&& cframe.ignoring
	118	&& (cframe.previous_cframe == NULL
	119	\|\| ! cframe.previous_cframe->ignoring))
	120	listing_list (2);
	121
	122	demand_empty_rest_of_line ();
76b0a8c0	123	}
252b5132	124
76b0a8c0	125	void
252b5132 RH	126	s_if (arg)
	127	int arg;
	128	{
	129	expressionS operand;
	130	struct conditional_frame cframe;
	131	int t;
	132	char *stop = NULL;
	133	char stopc;
	134
	135	if (flag_mri)
	136	stop = mri_comment_field (&stopc);
	137
76b0a8c0 KH	138	/* Leading whitespace is part of operand. */
76b0a8c0 KH	139	SKIP_WHITESPACE ();
252b5132 RH	140
	141	if (current_cframe != NULL && current_cframe->ignoring)
	142	{
	143	operand.X_add_number = 0;
	144	while (! is_end_of_line[(unsigned char) *input_line_pointer])
	145	++input_line_pointer;
	146	}
	147	else
	148	{
	149	expression (&operand);
	150	if (operand.X_op != O_constant)
	151	as_bad (_("non-constant expression in \".if\" statement"));
	152	}
	153
	154	switch ((operatorT) arg)
	155	{
	156	case O_eq: t = operand.X_add_number == 0; break;
	157	case O_ne: t = operand.X_add_number != 0; break;
	158	case O_lt: t = operand.X_add_number < 0; break;
	159	case O_le: t = operand.X_add_number <= 0; break;
	160	case O_ge: t = operand.X_add_number >= 0; break;
	161	case O_gt: t = operand.X_add_number > 0; break;
	162	default:
	163	abort ();
	164	return;
	165	}
	166
	167	/* If the above error is signaled, this will dispatch
	168	using an undefined result. No big deal. */
	169	initialize_cframe (&cframe);
	170	cframe.ignoring = cframe.dead_tree \|\| ! t;
	171	current_cframe = ((struct conditional_frame *)
	172	obstack_copy (&cond_obstack, &cframe, sizeof (cframe)));
	173
	174	if (LISTING_SKIP_COND ()
	175	&& cframe.ignoring
	176	&& (cframe.previous_cframe == NULL
	177	\|\| ! cframe.previous_cframe->ignoring))
	178	listing_list (2);
	179
	180	if (flag_mri)
	181	mri_comment_end (stop, stopc);
	182
	183	demand_empty_rest_of_line ();
76b0a8c0	184	}
252b5132 RH	185
	186	/* Get a string for the MRI IFC or IFNC pseudo-ops. */
	187
	188	static char *
	189	get_mri_string (terminator, len)
	190	int terminator;
	191	int *len;
	192	{
	193	char *ret;
	194	char *s;
	195
	196	SKIP_WHITESPACE ();
	197	s = ret = input_line_pointer;
	198	if (*input_line_pointer == '\'')
	199	{
	200	++s;
	201	++input_line_pointer;
	202	while (! is_end_of_line[(unsigned char) *input_line_pointer])
	203	{
	204	s++ = input_line_pointer++;
	205	if (s[-1] == '\'')
	206	{
	207	if (*input_line_pointer != '\'')
	208	break;
	209	++input_line_pointer;
	210	}
	211	}
	212	SKIP_WHITESPACE ();
	213	}
	214	else
	215	{
	216	while (*input_line_pointer != terminator
	217	&& ! is_end_of_line[(unsigned char) *input_line_pointer])
	218	++input_line_pointer;
	219	s = input_line_pointer;
	220	while (s > ret && (s[-1] == ' ' \|\| s[-1] == '\t'))
	221	--s;
	222	}
	223
	224	*len = s - ret;
	225	return ret;
	226	}
	227
	228	/* The MRI IFC and IFNC pseudo-ops. */
	229
	230	void
	231	s_ifc (arg)
	232	int arg;
	233	{
	234	char *stop = NULL;
	235	char stopc;
	236	char s1, s2;
	237	int len1, len2;
	238	int res;
	239	struct conditional_frame cframe;
	240
	241	if (flag_mri)
	242	stop = mri_comment_field (&stopc);
	243
	244	s1 = get_mri_string (',', &len1);
	245
	246	if (*input_line_pointer != ',')
	247	as_bad (_("bad format for ifc or ifnc"));
	248	else
249	++input_line_pointer;
250
251	s2 = get_mri_string (';', &len2);
252
253	res = len1 == len2 && strncmp (s1, s2, len1) == 0;
254
255	initialize_cframe (&cframe);
256	cframe.ignoring = cframe.dead_tree \|\| ! (res ^ arg);
257	current_cframe = ((struct conditional_frame *)
258	obstack_copy (&cond_obstack, &cframe, sizeof (cframe)));
259
260	if (LISTING_SKIP_COND ()
261	&& cframe.ignoring
262	&& (cframe.previous_cframe == NULL
263	\|\| ! cframe.previous_cframe->ignoring))
264	listing_list (2);
265
266	if (flag_mri)
267	mri_comment_end (stop, stopc);
268
269	demand_empty_rest_of_line ();
270	}
271
76b0a8c0	272	void
3fd9f047 TW	273	s_elseif (arg)
	274	int arg;
	275	{
3fd9f047 TW	276	if (current_cframe == NULL)
3fd9f047 TW	277	{
0e389e77	278	as_bad (_("\".elseif\" without matching \".if\""));
3fd9f047 TW	279	}
	280	else if (current_cframe->else_seen)
	281	{
0e389e77	282	as_bad (_("\".elseif\" after \".else\""));
3fd9f047 TW	283	as_bad_where (current_cframe->else_file_line.file,
	284	current_cframe->else_file_line.line,
	285	_("here is the previous \"else\""));
	286	as_bad_where (current_cframe->if_file_line.file,
	287	current_cframe->if_file_line.line,
	288	_("here is the previous \"if\""));
	289	}
	290	else
	291	{
	292	as_where (&current_cframe->else_file_line.file,
	293	&current_cframe->else_file_line.line);
	294
61b96bb4 AM	295	current_cframe->dead_tree \|= !current_cframe->ignoring;
	296	current_cframe->ignoring = current_cframe->dead_tree;
	297	}
3fd9f047	298
cdbc6895	299	if (current_cframe == NULL \|\| current_cframe->ignoring)
3fd9f047	300	{
3fd9f047 TW	301	while (! is_end_of_line[(unsigned char) *input_line_pointer])
3fd9f047 TW	302	++input_line_pointer;
61b96bb4 AM	303
	304	if (current_cframe == NULL)
	305	return;
3fd9f047	306	}
61b96bb4 AM	307	else
	308	{
	309	expressionS operand;
	310	int t;
cdbc6895	311
61b96bb4 AM	312	/* Leading whitespace is part of operand. */
61b96bb4 AM	313	SKIP_WHITESPACE ();
cdbc6895	314
61b96bb4 AM	315	expression (&operand);
	316	if (operand.X_op != O_constant)
	317	as_bad (_("non-constant expression in \".elseif\" statement"));
76b0a8c0	318
61b96bb4 AM	319	switch ((operatorT) arg)
	320	{
	321	case O_eq: t = operand.X_add_number == 0; break;
	322	case O_ne: t = operand.X_add_number != 0; break;
	323	case O_lt: t = operand.X_add_number < 0; break;
	324	case O_le: t = operand.X_add_number <= 0; break;
	325	case O_ge: t = operand.X_add_number >= 0; break;
	326	case O_gt: t = operand.X_add_number > 0; break;
	327	default:
	328	abort ();
	329	return;
	330	}
3fd9f047	331
61b96bb4 AM	332	current_cframe->ignoring = current_cframe->dead_tree \|\| ! t;
61b96bb4 AM	333	}
3fd9f047 TW	334
3fd9f047 TW	335	if (LISTING_SKIP_COND ()
3fd9f047 TW	336	&& (current_cframe->previous_cframe == NULL
3fd9f047 TW	337	\|\| ! current_cframe->previous_cframe->ignoring))
61b96bb4 AM	338	{
	339	if (! current_cframe->ignoring)
	340	listing_list (1);
	341	else
	342	listing_list (2);
	343	}
3fd9f047 TW	344
	345	demand_empty_rest_of_line ();
	346	}
	347
76b0a8c0	348	void
252b5132	349	s_endif (arg)
ab9da554	350	int arg ATTRIBUTE_UNUSED;
252b5132 RH	351	{
	352	struct conditional_frame *hold;
	353
	354	if (current_cframe == NULL)
	355	{
	356	as_bad (_("\".endif\" without \".if\""));
	357	}
	358	else
	359	{
	360	if (LISTING_SKIP_COND ()
	361	&& current_cframe->ignoring
	362	&& (current_cframe->previous_cframe == NULL
	363	\|\| ! current_cframe->previous_cframe->ignoring))
	364	listing_list (1);
	365
	366	hold = current_cframe;
	367	current_cframe = current_cframe->previous_cframe;
	368	obstack_free (&cond_obstack, hold);
	369	} /* if one pop too many */
	370
	371	if (flag_mri)
	372	{
	373	while (! is_end_of_line[(unsigned char) *input_line_pointer])
	374	++input_line_pointer;
	375	}
	376
	377	demand_empty_rest_of_line ();
76b0a8c0	378	}
252b5132	379
76b0a8c0	380	void
252b5132	381	s_else (arg)
ab9da554	382	int arg ATTRIBUTE_UNUSED;
252b5132 RH	383	{
	384	if (current_cframe == NULL)
	385	{
0e389e77	386	as_bad (_("\".else\" without matching \".if\""));
252b5132 RH	387	}
	388	else if (current_cframe->else_seen)
	389	{
0e389e77	390	as_bad (_("duplicate \"else\""));
252b5132 RH	391	as_bad_where (current_cframe->else_file_line.file,
	392	current_cframe->else_file_line.line,
	393	_("here is the previous \"else\""));
	394	as_bad_where (current_cframe->if_file_line.file,
	395	current_cframe->if_file_line.line,
	396	_("here is the previous \"if\""));
	397	}
	398	else
	399	{
	400	as_where (&current_cframe->else_file_line.file,
	401	&current_cframe->else_file_line.line);
	402
61b96bb4 AM	403	current_cframe->ignoring =
	404	current_cframe->dead_tree \| !current_cframe->ignoring;
	405
	406	if (LISTING_SKIP_COND ()
	407	&& (current_cframe->previous_cframe == NULL
	408	\|\| ! current_cframe->previous_cframe->ignoring))
252b5132	409	{
61b96bb4 AM	410	if (! current_cframe->ignoring)
	411	listing_list (1);
	412	else
	413	listing_list (2);
	414	}
252b5132 RH	415
252b5132 RH	416	current_cframe->else_seen = 1;
61b96bb4	417	}
252b5132 RH	418
	419	if (flag_mri)
	420	{
	421	while (! is_end_of_line[(unsigned char) *input_line_pointer])
	422	++input_line_pointer;
	423	}
	424
	425	demand_empty_rest_of_line ();
76b0a8c0	426	}
252b5132	427
76b0a8c0	428	void
252b5132 RH	429	s_ifeqs (arg)
	430	int arg;
	431	{
	432	char s1, s2;
	433	int len1, len2;
	434	int res;
	435	struct conditional_frame cframe;
	436
	437	s1 = demand_copy_C_string (&len1);
	438
	439	SKIP_WHITESPACE ();
	440	if (*input_line_pointer != ',')
	441	{
	442	as_bad (_(".ifeqs syntax error"));
	443	ignore_rest_of_line ();
	444	return;
	445	}
	446
	447	++input_line_pointer;
	448
	449	s2 = demand_copy_C_string (&len2);
	450
	451	res = len1 == len2 && strncmp (s1, s2, len1) == 0;
	452
	453	initialize_cframe (&cframe);
	454	cframe.ignoring = cframe.dead_tree \|\| ! (res ^ arg);
	455	current_cframe = ((struct conditional_frame *)
	456	obstack_copy (&cond_obstack, &cframe, sizeof (cframe)));
	457
	458	if (LISTING_SKIP_COND ()
	459	&& cframe.ignoring
	460	&& (cframe.previous_cframe == NULL
	461	\|\| ! cframe.previous_cframe->ignoring))
	462	listing_list (2);
	463
	464	demand_empty_rest_of_line ();
76b0a8c0	465	}
252b5132	466
76b0a8c0	467	int
252b5132 RH	468	ignore_input ()
	469	{
	470	char *s;
	471
	472	s = input_line_pointer;
	473
abd63a32	474	if (NO_PSEUDO_DOT \|\| flag_m68k_mri)
252b5132 RH	475	{
	476	if (s[-1] != '.')
	477	--s;
	478	}
	479	else
	480	{
	481	if (s[-1] != '.')
	482	return (current_cframe != NULL) && (current_cframe->ignoring);
	483	}
	484
	485	/* We cannot ignore certain pseudo ops. */
	486	if (((s[0] == 'i'
	487	\|\| s[0] == 'I')
	488	&& (!strncasecmp (s, "if", 2)
	489	\|\| !strncasecmp (s, "ifdef", 5)
	490	\|\| !strncasecmp (s, "ifndef", 6)))
	491	\|\| ((s[0] == 'e'
	492	\|\| s[0] == 'E')
	493	&& (!strncasecmp (s, "else", 4)
	494	\|\| !strncasecmp (s, "endif", 5)
	495	\|\| !strncasecmp (s, "endc", 4))))
	496	return 0;
	497
	498	return (current_cframe != NULL) && (current_cframe->ignoring);
76b0a8c0	499	}
252b5132	500
76b0a8c0	501	static void
252b5132 RH	502	initialize_cframe (cframe)
	503	struct conditional_frame *cframe;
	504	{
	505	memset (cframe, 0, sizeof (*cframe));
	506	as_where (&cframe->if_file_line.file,
	507	&cframe->if_file_line.line);
	508	cframe->previous_cframe = current_cframe;
	509	cframe->dead_tree = current_cframe != NULL && current_cframe->ignoring;
	510	cframe->macro_nest = macro_nest;
	511	}
	512
	513	/* Give an error if a conditional is unterminated inside a macro or
	514	the assembly as a whole. If NEST is non negative, we are being
	515	called because of the end of a macro expansion. If NEST is
	516	negative, we are being called at the of the input files. */
	517
	518	void
	519	cond_finish_check (nest)
	520	int nest;
	521	{
	522	if (current_cframe != NULL && current_cframe->macro_nest >= nest)
	523	{
	524	if (nest >= 0)
	525	as_bad (_("end of macro inside conditional"));
	526	else
	527	as_bad (_("end of file inside conditional"));
	528	as_bad_where (current_cframe->if_file_line.file,
	529	current_cframe->if_file_line.line,
	530	_("here is the start of the unterminated conditional"));
	531	if (current_cframe->else_seen)
	532	as_bad_where (current_cframe->else_file_line.file,
	533	current_cframe->else_file_line.line,
	534	_("here is the \"else\" of the unterminated conditional"));
	535	}
	536	}
	537
	538	/* This function is called when we exit out of a macro. We assume
	539	that any conditionals which began within the macro are correctly
	540	nested, and just pop them off the stack. */
	541
	542	void
	543	cond_exit_macro (nest)
	544	int nest;
	545	{
	546	while (current_cframe != NULL && current_cframe->macro_nest >= nest)
	547	{
	548	struct conditional_frame *hold;
	549
	550	hold = current_cframe;
	551	current_cframe = current_cframe->previous_cframe;
	552	obstack_free (&cond_obstack, hold);
	553	}
	554	}