MultiSource/Benchmarks/Prolangs-C/bison/bison.simple

#line 2 "bison.simple"
/* Skeleton output parser for bison,
   copyright (C) 1984 Bob Corbett and Richard Stallman

		       NO WARRANTY

  BECAUSE THIS PROGRAM IS LICENSED FREE OF CHARGE, WE PROVIDE ABSOLUTELY
NO WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW.  EXCEPT
WHEN OTHERWISE STATED IN WRITING, FREE SOFTWARE FOUNDATION, INC,
RICHARD M. STALLMAN AND/OR OTHER PARTIES PROVIDE THIS PROGRAM "AS IS"
WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY
AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE PROGRAM PROVE
DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR
CORRECTION.

 IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL RICHARD M.
STALLMAN, THE FREE SOFTWARE FOUNDATION, INC., AND/OR ANY OTHER PARTY
WHO MAY MODIFY AND REDISTRIBUTE THIS PROGRAM AS PERMITTED BELOW, BE
LIABLE TO YOU FOR DAMAGES, INCLUDING ANY LOST PROFITS, LOST MONIES, OR
OTHER SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
USE OR INABILITY TO USE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR
DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY THIRD PARTIES OR
A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS) THIS
PROGRAM, EVEN IF YOU HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH
DAMAGES, OR FOR ANY CLAIM BY ANY OTHER PARTY.

		GENERAL PUBLIC LICENSE TO COPY

  1. You may copy and distribute verbatim copies of this source file
as you receive it, in any medium, provided that you conspicuously and
appropriately publish on each copy a valid copyright notice "Copyright
(C) 1985 Free Software Foundation, Inc."; and include following the
copyright notice a verbatim copy of the above disclaimer of warranty
and of this License.  You may charge a distribution fee for the
physical act of transferring a copy.

  2. You may modify your copy or copies of this source file or
any portion of it, and copy and distribute such modifications under
the terms of Paragraph 1 above, provided that you also do the following:

    a) cause the modified files to carry prominent notices stating
    that you changed the files and the date of any change; and

    b) cause the whole of any work that you distribute or publish,
    that in whole or in part contains or is a derivative of this
    program or any part thereof, to be licensed at no charge to all
    third parties on terms identical to those contained in this
    License Agreement (except that you may choose to grant more extensive
    warranty protection to some or all third parties, at your option).

    c) You may charge a distribution fee for the physical act of
    transferring a copy, and you may at your option offer warranty
    protection in exchange for a fee.

Mere aggregation of another unrelated program with this program (or its
derivative) on a volume of a storage or distribution medium does not bring
the other program under the scope of these terms.

  3. You may copy and distribute this program (or a portion or derivative
of it, under Paragraph 2) in object code or executable form under the terms
of Paragraphs 1 and 2 above provided that you also do one of the following:

    a) accompany it with the complete corresponding machine-readable
    source code, which must be distributed under the terms of
    Paragraphs 1 and 2 above; or,

    b) accompany it with a written offer, valid for at least three
    years, to give any third party free (except for a nominal
    shipping charge) a complete machine-readable copy of the
    corresponding source code, to be distributed under the terms of
    Paragraphs 1 and 2 above; or,

    c) accompany it with the information you received as to where the
    corresponding source code may be obtained.  (This alternative is
    allowed only for noncommercial distribution and only if you
    received the program in object code or executable form alone.)

For an executable file, complete source code means all the source code for
all modules it contains; but, as a special exception, it need not include
source code for modules which are standard libraries that accompany the
operating system on which the executable file runs.

  4. You may not copy, sublicense, distribute or transfer this program
except as expressly provided under this License Agreement.  Any attempt
otherwise to copy, sublicense, distribute or transfer this program is void and
your rights to use the program under this License agreement shall be
automatically terminated.  However, parties who have received computer
software programs from you with this License Agreement will not have
their licenses terminated so long as such parties remain in full compliance.

  5. If you wish to incorporate parts of this program into other free
programs whose distribution conditions are different, write to the Free
Software Foundation at 675 Mass Ave, Cambridge, MA 02139.  We have not yet
worked out a simple rule that can be stated here, but we will often permit
this.  We will be guided by the two goals of preserving the free status of
all derivatives of our free software and of promoting the sharing and reuse of
software.


In other words, you are welcome to use, share and improve this program.
You are forbidden to forbid anyone else to use, share and improve
what you give them.   Help stamp out software-hoarding!  */

/* This is the parser code that is written into each bison parser
  when the %semantic_parser declaration is not specified in the grammar.
  It was written by Richard Stallman by simplifying the hairy parser
  used when %semantic_parser is specified.  */

/* Note: there must be only one dollar sign in this file.
   It is replaced by the list of actions, each action
   as one case of the switch.  */

#define yyerrok		(yyp->yyerrstatus = 0)
#define yyclearin	(yychar = YYEMPTY)
#define YYEMPTY		-2
#define YYEOF		0
#define YYFAIL		goto yyerrlab;
#define YYACCEPT	goto yyaccept
#define YYABORT		goto yyabort

#define YYTERROR	1

#ifndef YYIMPURE
#define YYLEX		yylex(currentfile)
#endif

static char *dummy = NULL;
char **_yytext = &dummy;
static YYSTYPE dummys;
YYSTYPE *_yylval = &dummys;
static YYLTYPE dummyl;
YYLTYPE *_yylloc = &dummyl;
static int dummyp;
int *_yyppval = &dummyp;

#ifdef YYDEBUG
int yydebug = 0;		/*  nonzero means print parse debug info */
int yytrace = 0;		/*  nonzero means print high-level parse
				    trace */
#endif

#ifndef YYPURE
#define YYLEX		yylex(currentfile, &yylval, &yylloc)
#endif

/* If nonreentrant, generate the variables here */

#ifndef YYIMPURE

int	yyn;

#endif  /* YYIMPURE */


/*  YYMAXDEPTH indicates the initial size of the parser's stacks	*/

#ifndef	YYMAXDEPTH
#define YYMAXDEPTH 200
#endif

/*  YYMAXLIMIT is the maximum size the stacks can grow to
    (effective only if the built-in stack extension method is used).  */

#ifndef YYMAXLIMIT
#define YYMAXLIMIT 10000
#endif

#define YYMAXFORKDEPTH 20

typedef struct parsestate {
	struct parsestate *flink, *blink;
	char *text;
  	YYSTYPE lval;
	YYLTYPE lloc;
	int cur_token_number;
	int yychar;
	int blocked;
	int lineno;		/* line number containing PP token */
	int yystate;
	int yyerrstatus;
	int yynerr;		/* number of parse errors so far */
	short *yyss, *yyssp;	/* state stack and state tos */
	YYSTYPE *yyvs, *yyvsp, *last_reduction;	/* val stack and val tos */
	YYSTYPE *tos_stack[YYMAXFORKDEPTH], **tos_tos;
#ifdef YYLSP_NEEDED
	YYLTYPE *yyls, *yylsp;	/* line stack and line tos */
#endif
	unsigned short flags_stack[YYMAXFORKDEPTH], *flags; /* control flags */
	int  data_stack[YYMAXFORKDEPTH], *data; /* client specific data */
	/* The following manage the correspondence between the
	   two parses for an #ifdef. "pending_join" is the
	   partner that will be next joined to. "pending_endif"
	   is the partner that will be awoken on the next ifdef. */
	struct parsestate *pending_join_stack[YYMAXFORKDEPTH], **pending_join;
	struct parsestate *pending_endif_stack[YYMAXFORKDEPTH], **pending_endif;
	short yymaxdepth;	/* max depth of current stack */
#ifdef YYDEBUG
	char *branch_stack[YYMAXFORKDEPTH], **branch; 
#endif
} *parse;

#define SEEN_ENDIF_BIT 		0x01
#define SEEN_PP_TOKEN_BIT	0x02
#define JOIN_PENDING_BIT 	0x04
#define IFDEF_FORK_BIT 		0x08
#define JUST_SHIFTED_BIT	0x10
#define ACCEPTED_BIT		0x20
#define ABORTED_BIT		0x40
#define ACTIVE_BIT		0x80
#define DONE_SOMETHING_BIT	0x100
#define SEEN_ENDIF(p) 		(*(p)->flags & SEEN_ENDIF_BIT)
#define SEEN_PP_TOKEN(p)	(*(p)->flags & SEEN_PP_TOKEN_BIT)
#define JOIN_PENDING(p) 	(*(p)->flags & JOIN_PENDING_BIT)
#define IFDEF_FORK(p) 		(*(p)->flags & IFDEF_FORK_BIT)
#define JUST_SHIFTED(p)		(*(p)->flags & JUST_SHIFTED_BIT)
#define ACCEPTED(p) 		(*(p)->flags & ACCEPTED_BIT)
#define ABORTED(p) 		(*(p)->flags & ABORTED_BIT)
#define ACTIVE(p) 		(*(p)->flags & ACTIVE_BIT)
#define DONE_SOMETHING(p) 	(*(p)->flags & DONE_SOMETHING_BIT)
#define SET_SEEN_ENDIF(p) 	(*(p)->flags |= SEEN_ENDIF_BIT)
#define SET_SEEN_PP_TOKEN(p) 	(*(p)->flags |= SEEN_PP_TOKEN_BIT)
#define SET_JOIN_PENDING(p) 	(*(p)->flags |= JOIN_PENDING_BIT)
#define SET_IFDEF_FORK(p) 	(*(p)->flags |= IFDEF_FORK_BIT)
#define SET_JUST_SHIFTED(p) 	(*(p)->flags |= JUST_SHIFTED_BIT)
#define SET_ACCEPTED(p) 	(*(p)->flags |= ACCEPTED_BIT)
#define SET_ABORTED(p) 		(*(p)->flags |= ABORTED_BIT)
#define SET_ACTIVE(p) 		(*(p)->flags |= ACTIVE_BIT)
#define SET_DONE_SOMETHING(p) 	(*(p)->flags |= DONE_SOMETHING_BIT)
#define UNSET_SEEN_ENDIF(p) 	(*(p)->flags &= ~SEEN_ENDIF_BIT)
#define UNSET_SEEN_PP_TOKEN(p) 	(*(p)->flags &= ~SEEN_PP_TOKEN_BIT)
#define UNSET_JOIN_PENDING(p) 	(*(p)->flags &= ~JOIN_PENDING_BIT)
#define UNSET_IFDEF_FORK(p) 	(*(p)->flags &= ~IFDEF_FORK_BIT)
#define UNSET_JUST_SHIFTED(p) 	(*(p)->flags &= ~JUST_SHIFTED_BIT)
#define UNSET_ACCEPTED(p) 	(*(p)->flags &= ~ACCEPTED_BIT)
#define UNSET_ABORTED(p) 	(*(p)->flags &= ~ABORTED_BIT)
#define UNSET_ACTIVE(p) 	(*(p)->flags &= ~ACTIVE_BIT)
#define UNSET_DONE_SOMETHING(p) (*(p)->flags &= ~DONE_SOMETHING_BIT)
#define UNSET_ALL(p)		(*(p)->flags = 0)

#ifdef YYDEBUG
void
dumpparse(p)
parse p;
{
    short *ss;

    printf("parse %x, flink=%x, blink=%x, token=%d, yychar=%d\n",
	   p, p->flink, p->blink, p->cur_token_number, p->yychar);
    printf("\tblocked=%d, lineno=%d, yystate=%d, yyerrstatus=%d, yynerr=%d\n",
	   p->blocked, p->lineno, p->yystate, p->yyerrstatus, p->yynerr);
    printf("\tstate-stack: ");
    for (ss = p->yyss; ss <= p->yyssp; ss++) {
	printf(" %d", *ss);
	if (ss - p->yyss == *p->tos_tos - p->yyvs)
	    printf(" t");
    }
    printf("\n\n");
}

#endif

#if 0
extern int yylineno();		/* current line number per the scanner */
#endif

int id;

YYSTYPE (*yyfork)();
YYSTYPE (*yyjoin)();
void	(*yyelse)();
void	(*yyendif)();
void    (*yyfinish)();
void	(*yyswitch)();
int	(*yyskip)();

#include "preprocessor.h"
#include "alloc.h"

extern FILE *errfile;

parse
start_parse()
{
    register parse p;
#ifdef YYDEBUG
    if (yydebug)
	fprintf(errfile, "Starting parse\n");
#endif
    p = (parse)Malloc(sizeof *p);

    p->yystate = 0;
    p->yyerrstatus = 0;
    p->yynerr = 0;
    p->blocked = 0;
    p->cur_token_number = -1;
    p->yychar = YYEMPTY;
    p->last_reduction = 0;

    /* Initialize stack pointers.  Waste one element of value and
     * location stack so that they stay on the same level as the state
     * stack.
     */
    p->yyss = (short *)Malloc(sizeof(short) * YYMAXDEPTH);
    p->yyssp = p->yyss - 1;
    p->yyvsp = p->yyvs = (YYSTYPE *)Malloc(sizeof(YYSTYPE) * YYMAXDEPTH);
    p->tos_tos = &p->tos_stack[0];
    *p->tos_tos = p->yyvsp;
    p->flags = &p->flags_stack[0];
    *p->flags = 0;
    p->data = &p->data_stack[0];
    *p->data = 0;
    p->pending_join = &p->pending_join_stack[0];
    p->pending_endif = &p->pending_endif_stack[0];
    *p->pending_join = *p->pending_endif = 0;
#ifdef YYLSP_NEEDED
    p->yylsp = p->yyls = (YYLTYPE *)Malloc(sizeof(YYLTYPE) * YYMAXDEPTH);
#endif
    p->yymaxdepth = YYMAXDEPTH;
    /* make it a circular linked list */
    p->flink = p->blink = p;
#ifdef YYDEBUG
    p->branch = &p->branch_stack[0];
    *p->branch = "TRUE branch";
#endif
    return p;
}

kill_parse(p)
register parse p;
{
    Free(p->yyss);
    Free(p->yyvs);
#ifdef YYLSP_NEEDED
    Free(p->yyls);
#endif
    Free(p);
}

unify_parses(p1, p2)
parse p1, p2;
{
    register short *s1 = p1->yyssp;
    register short *s2 = p2->yyssp;

    if (*p1->pending_join != p2 || *p2->pending_join != p1)
	return 0;

    if (JUST_SHIFTED(p1) || JUST_SHIFTED(p2)) 
	return 0;

    if (!ACTIVE(p1) || !ACTIVE(p2)) 
	return 0;

    if ((!DONE_SOMETHING(p1) && !DONE_SOMETHING(p2)) ||
	(ACCEPTED(p1) && ACCEPTED(p2))) {
#ifdef YYDEBUG	       
	if (yydebug)
	    fprintf(errfile, "Joining parse %x to parse %x\n", p1, p2);
#endif
	return 1;
    }
    
    if ((p1->yyvsp > *p1->tos_tos+1) || (p2->yyvsp > *p2->tos_tos+1))
	return 0;
    
    while (s1 != p1->yyss && s2 != p2->yyss) {
	if (*s1 != *s2)
	    break;
	s1--; s2--;
    }

    if (s1 == p1->yyss && s2 == p2->yyss) {
#ifdef YYDEBUG	       
	if (yydebug) {
	    fprintf(errfile, "Joining parse %x to parse %x\n", p1, p2);
	}
#endif
	return 1;
    }
    return 0;
}

void realloc_stack(as, p)
    ScanPtr as;
    register parse p;
{
    /* Give user a chance to reallocate the stack. */


    /* Get the current used size of the three stacks, in elements.  */
    int size = p->yyssp - p->yyss + 1;

    if (p->yymaxdepth >= YYMAXLIMIT)
	yyerror(as, "parser stack overflow");

    p->yymaxdepth *= 2;
    if (p->yymaxdepth > YYMAXLIMIT)
	p->yymaxdepth = YYMAXLIMIT;

    p->yyss = (short *) Realloc(p->yyss,
				p->yymaxdepth * (sizeof (*p->yyssp)));
    p->yyvs = (YYSTYPE *) Realloc(p->yyvs, 
				  p->yymaxdepth * (sizeof (*p->yyvsp)));
#ifdef YYLSP_NEEDED
    p->yyls = (YYLTYPE *) Realloc(p->yyls, 
				  p->yymaxdepth * (sizeof (*p->yylsp)));
#endif

    p->yyssp = p->yyss + size - 1;
    p->yyvsp = p->yyvs + size - 1;
#ifdef YYLSP_NEEDED
    p->yylsp = p->yyls + size - 1;
#endif

#ifdef YYDEBUG
    if (yydebug)
	fprintf(errfile, "Stack size increased to %d\n", p->yymaxdepth);
#endif

#if 0
    if (p->yyssp >= p->yyss + p->yymaxdepth - 1)
	return
#endif
}

#define REDUCTION 1

#if 0
static parse
next_applicable_parse(p, parselist)
register parse p, parselist;
{
    register parse l = parselist->flink;

    while (l != p) {
	if (l->cur_token_number == p->cur_token_number)
	    break;
	l = l->flink;
    }
    return l == p ? NULL : l;
}
#endif

static void
notify_of_endif(p, limit, activelist, cur_token_number)
    parse p;
    parse limit;
    parse *activelist;
{
    parse *pending;

    --p->pending_endif;
    p->cur_token_number = cur_token_number;
    p->yychar = YYEMPTY;
    SET_SEEN_ENDIF(p);
    SET_SEEN_PP_TOKEN(p);
    /* if p isn't active, make it so and put it on the activelist */
    if (!ACTIVE(p)) {
	SET_ACTIVE(p);
	if (*activelist == NULL) {
	    *activelist = p;
	    (*activelist)->flink = (*activelist)->blink = *activelist;
	} else {
	    (*activelist)->blink->flink = p;
	    p->flink = *activelist;
	    p->blink = (*activelist)->blink;
	    (*activelist)->blink = p;
	}
    }

    for (pending = p->pending_join; *pending != limit; pending--) {
	notify_of_endif(*pending, p, activelist, cur_token_number);
    }

}

static parse
find_next_parse(parselist, cur_token_number)
register parse parselist;
{
    register parse l, best_parse;
    int parse_val, best_parse_val;

    if (parselist->flink == parselist)
    	if (ACCEPTED(parselist) || ABORTED(parselist))
	    return NULL;
	else
    	    return parselist;

    l = parselist;
    best_parse_val = -2;
    best_parse = NULL;
    do {
	if (ACCEPTED(l) || ABORTED(l)) {
	    l = l->flink;
	    continue;
	}
	else if (l->cur_token_number < cur_token_number) 
	    parse_val = 100000;
	else 
	    parse_val = 0;

	parse_val += l->yyssp - l->yyss;
	if (parse_val > best_parse_val) {
	    best_parse_val = parse_val;
	    best_parse = l;
	} else if (parse_val == best_parse_val &&
		   *l->yyssp > *best_parse->yyssp) {
	    best_parse_val = parse_val;
	    best_parse = l;
	}
	    
	l = l->flink;
    } while (l != parselist);
    return best_parse;
}

#define FALSE 0
#define TRUE 1

all_blocked(parselist, cur_token_number)
parse parselist;
{
    register parse l = parselist;
    do {
	if (l->cur_token_number != cur_token_number)
	    return FALSE;
	l = l->flink;
    } while (l != parselist);
    return TRUE;
}

static parse merge_parses(yyp, ap, activelist, currentfile)
    parse yyp, ap;
    parse *activelist;
    FilePtr currentfile;
{
    parse tmp;
    
    if (!IFDEF_FORK(yyp)) {
	/* swap ap and yyp so that the result of the join
	   (yyp) is the true branch of the fork */
	tmp = ap;
	ap = yyp;
	yyp = tmp;
    }
#ifdef YYDEBUG
    if (yydebug)
	fprintf(errfile, "Joining parse 0x%x and 0x%x.\n", 
		yyp, ap);
#endif		
    if (yyjoin) {
	if (!yyp->last_reduction) 
	    yyp->last_reduction = yyp->yyvsp;
	if (!ap->last_reduction) 
	    ap->last_reduction = ap->yyvsp;
	*yyp->yyvsp = (*yyjoin)(yyp->last_reduction,
				ap->last_reduction,
				yyp->data, ap->data,
				&currentfile->cpp_skipping);
    }
    --yyp->pending_join;
    --yyp->data;
    --yyp->flags;
    --yyp->tos_tos;
#ifdef YYDEBUG
    --yyp->branch;
#endif			
    
    /* get rid of the duplicate parse */
    ap->blink->flink = ap->flink;
    ap->flink->blink = ap->blink;
    if (ap == *activelist)
	*activelist = ap->flink;
    kill_parse(ap);
    return yyp;
}

static void merge_active(activelist, currentfile)
    parse *activelist;
    FilePtr currentfile;
{
    parse yyp, ap;
    int parses_merged;
    
    /*
     * See if there are any parses that we can join.
     */
    parses_merged = 1;
    while (parses_merged && (*activelist)->flink != *activelist) {
	parses_merged = 0;
	yyp = *activelist;
	do {
	    ap = *yyp->pending_join;
	    if (unify_parses(yyp, ap)) {
		yyp = merge_parses(yyp, ap, activelist, currentfile);
		parses_merged = 1;
	    }
	    yyp = yyp->flink;
	} while (yyp != *activelist);
    }
}

#line 607 "bison.simple"
int yyparse(currentfile)
    FilePtr currentfile;
{
    int yychar1; /*  lookahead token as an internal (translated) token number */

#ifndef YYPURE
    int yyn;
#endif

#ifdef YYDEBUG
    extern int yydebug;
#endif

    YYSTYPE yyval;    	/* the variable used to return */
    			/* semantic values from the action */
    			/* routines */
    int yylen;
    register parse yyp;
    parse ap, activelist;
    int curtoken, retval;
    char *curtext, **oldtext;
    YYSTYPE curlval, *oldlval;
    YYLTYPE curlloc, *oldlloc;
    int cur_token_number = 0;


    oldtext = _yytext;
    oldlval = _yylval;
    oldlloc = _yylloc;
    
    activelist = start_parse();
    SET_ACTIVE(activelist);
     
    /* Go through parses in round-robin fashion. Activelist is a circular */
    /* doubly linked list. */ 
    while (yyp = find_next_parse(activelist, cur_token_number)) {
	_yytext = &(yyp->text);
	_yylval = &(yyp->lval);
	_yylloc = &(yyp->lloc);
#ifdef YYDEBUG
	if (yydebug)
	    fprintf(errfile, "Resuming parser %x %s\n", yyp, *yyp->branch);
#endif
	if (yyswitch) 
	    (*yyswitch)(yyp->data, &currentfile->cpp_skipping);

	/*
	 * Figure out where to resume.  If this parse has never
	 * seen a token, we start below the test statements, otherwise
	 * we start where we left off.
	 */
#if 1
	if (yyp->blocked == REDUCTION) {
#ifdef YYDEBUG
	    if (yydebug) 
		fprintf(errfile, "yyp->blocked == REDUCTION, yyp->token = %d, %d\n", yyp->cur_token_number, cur_token_number);
#endif
	    goto yyresume;
	}
	else 
#endif
	    if (SEEN_PP_TOKEN(yyp)) {
#ifdef YYDEBUG
		if (yydebug) 
		    fprintf(errfile, "SEEN_PP_TOKEN");
#endif
		goto yyresume;
	}
	else if (yyp->cur_token_number < 0) {
	    /*
	     * This is the start-up case for the parser.  We have
	     * to set the token counter so that we will read the first
	     * token and then fall through to push the initial state.
	     */
	    yyp->cur_token_number = cur_token_number;
	} else 
	    goto yyresume;

        /*
	 * Push a new state, which is found in yystate .  In all
	 * cases, when you get here, the value and location stacks
	 * have just been pushed.  so pushing a state here evens the
	 * stacks.
  	 */
    yynewstate:
#ifdef YYDEBUG
	    if (yydebug) 
		fprintf(errfile, "yynewstate: ");
#endif
	*++yyp->yyssp = yyp->yystate;
	SET_DONE_SOMETHING(yyp);

	if (yyp->yyssp >= yyp->yyss + yyp->yymaxdepth - 1)
	    realloc_stack(currentfile->as, yyp);
#ifdef YYDEBUG
	if (yydebug) {
	    short *ssp1 = yyp->yyss - 1;
	    fprintf(errfile, "Entering state %d ", yyp->yystate);
	    fprintf (errfile, "state stack now");
	    while (ssp1 != yyp->yyssp)
		fprintf (errfile, " %d", *++ssp1);
	    fprintf (errfile, "\n");
	}
#endif

	/*
	 * We've already done the reduction.  Now see if we can join this
	 * parse with its partner.
	 */
	if (SEEN_ENDIF(yyp) && (ap = *yyp->pending_join)) {
	    /* we should really make sure that both parses can be
	       reduced here */
	    if (unify_parses(yyp, ap))
		yyp = merge_parses(yyp, ap, &activelist, currentfile);
	}

#if 2	
	/*
	 * If we are here and blocked == REDUCTION, then we just
	 * did a reduction so we should block to see if there is a better 
	 * candidate parse for reduction.
	 */
	if (yyp->blocked == REDUCTION)
	   continue; 
#endif

	/* Do appropriate processing given the current state.  Read
	 * a lookahead token if we need one and don't already have
	 * one.
	 */
    yyresume:
#ifdef YYDEBUG
	if (yydebug) 
	    fprintf(errfile, "yyresume: ");
#endif

	/* First try to decide what to do without reference to
	 * lookahead token.
	 */

	yyn = yypact[yyp->yystate];
	if (yyn == YYFLAG)
	    goto yydefault;

	/* Not known => get a lookahead token if don't already have
	 * one.
	 */

	/* yychar is either YYEMPTY or YYEOF or a valid token in
	 * external form.
	 */

	if (yyp->yychar == YYEMPTY) {
	    register parse newp;
	    int need_new_token;

	    /*
	     * Synchronize on input.  Suspend this parse if other
	     * parses haven't read the current token.
	     */
	    if (!(need_new_token = all_blocked(activelist, cur_token_number)) &&
		yyp->cur_token_number == cur_token_number)
		continue;

	    if (need_new_token) {
#ifdef YYDEBUG
		if (yydebug)
		    fprintf(errfile, "Reading a token: ");
#endif
		yyp->yychar = curtoken = YYLEX;
		curtext = yytext;
		curlval = yylval;
		curlloc = yylloc;
		yyp->cur_token_number = ++cur_token_number;
	    } else {
		yyp->yychar = curtoken;
		yyp->text = curtext;
		yyp->lval = curlval;
		yyp->lloc = curlloc;
		yyp->cur_token_number = cur_token_number;
	    }

	    switch (yyp->yychar) {
		parse tail;
		int token_val;

	    case PPELSE:
	    case PPELIF:
#ifdef YYDEBUG
		if (yydebug)
		    fprintf(errfile, "Next token is ELSE\n");
#endif
		token_val = yyp->yychar;

		/*
		 * Swap role of active and sleeping parses
		 * by putting all currently active parses to sleep
		 * and waking all their partners.
		 */
		ap = activelist;        /* save old activelist */
		activelist = NULL;	/* nothing currently active */
		tail = ap;
		
		/*
		 * Now put the relevant sleeping parses back on
		 * activelist.
		 */
	    	{
		    parse nextap = 0, partner;
		    
		    for (; ap && nextap != tail; ap = nextap) {
			nextap = ap->flink;
			partner = *ap->pending_endif;
			UNSET_ACTIVE(ap);
			if (!ACTIVE(partner)) {
			    if (activelist == NULL) {
				activelist = partner;
				activelist->flink = activelist->blink =
				    activelist;
			    } else {
				/* Put parse on end. Is this necessary? */
				activelist->blink->flink = partner;
				partner->flink = activelist;
				partner->blink = activelist->blink;
				activelist->blink = partner;
			    }
			    /* force this parse to read new token */
			    partner->cur_token_number = cur_token_number;
			    /* mark this parse as having just seen a
			       preprocessor token */
			    UNSET_ALL(partner);
			    SET_SEEN_PP_TOKEN(partner);
			    SET_ACTIVE(partner);
			}
		    }		/* for loop */
		}		/* compound stmt */

		if (yyelse) 
		    if (IFDEF_FORK(yyp))
			(*yyelse)(yyp->data, (*yyp->pending_endif)->data);
		    else
			(*yyelse)((*yyp->pending_endif)->data, yyp->data);


		yyp->yychar = YYEMPTY;
		yyp = activelist->blink;
		if (token_val == PPELSE) {
		    continue;
		} else {
		    /* fall through to do IF part of PPELIF case */ ;
		    yyp->yychar = PPELIF;
#ifdef YYDEBUG
		    if (yydebug)
			fprintf(errfile, "Next token was really ELSIF\n");
#endif
		}
	    case PPIFDEF:
	    case PPIF:
	    case PPIFNDEF:

#ifdef YYDEBUG
		if (yydebug)	
		    fprintf(errfile, "Next token is IFDEF, IFNDEF, or IF. ");
#endif
		/* save current tos for yyvs */
		*(++yyp->tos_tos) = yyp->yyvsp;
		++yyp->flags;
		SET_JOIN_PENDING(yyp);
		UNSET_SEEN_ENDIF(yyp);
		SET_SEEN_PP_TOKEN(yyp);
		SET_IFDEF_FORK(yyp);
		SET_ACTIVE(yyp);
		UNSET_DONE_SOMETHING(yyp);
		++yyp->pending_join;
		++yyp->pending_endif;
		++yyp->data;
		
		/*
		 * fork an alternate parse for this active parse.
		 */
		newp = start_parse();
#ifdef YYDEBUG
		if (yydebug)
		    fprintf(errfile, 
			    "Splitting parse 0x%x. New parse is 0x%x.\n", 
			    yyp, newp);
#endif		

#ifdef YYDEBUG
		++yyp->branch;
		*yyp->branch = "TRUE branch";
		bcopy(yyp->branch_stack, newp->branch_stack, sizeof
		      newp->branch_stack);
		newp->branch = newp->branch_stack + (yyp->branch -
						     yyp->branch_stack);
		*newp->branch = "FALSE branch";
#endif
		bcopy(yyp->yyss, newp->yyss,
		      (yyp->yyssp - yyp->yyss + 1) * (sizeof *yyp->yyss));
		newp->yyssp = newp->yyss + (yyp->yyssp - yyp->yyss);
		bcopy(yyp->yyvs, newp->yyvs,
		      (yyp->yyvsp - yyp->yyvs + 1) * (sizeof *yyp->yyvs));
		newp->yyvsp = newp->yyvs + (yyp->yyvsp - yyp->yyvs);
#ifdef YYLSP_NEEDED
		bcopy(yyp->yyls, newp->yyls,
		      (yyp->yylsp - yyp->yyls + 1) * (sizeof *yyp->yyls));
		newp->yylsp = newp->yyls + (yyp->yylsp - yyp->yyls);
#endif

		{
		    int i;
		    for (i = 0; &yyp->tos_stack[i] <= yyp->tos_tos; i++)
			newp->tos_stack[i] = newp->yyvs
			    + (yyp->tos_stack[i] - yyp->yyvs);
		}
		newp->tos_tos = newp->tos_stack
		    + (yyp->tos_tos - yyp->tos_stack);

		newp->lineno = yyp->lineno = yylineno(currentfile->as);
		newp->yystate = yyp->yystate;
		newp->yyerrstatus = yyp->yyerrstatus;
		newp->yynerr = yyp->yynerr;
		newp->yymaxdepth = yyp->yymaxdepth;
		
		bcopy(yyp->flags_stack, newp->flags_stack,  
		      sizeof newp->flags_stack);
		newp->flags =
		    newp->flags_stack + (yyp->flags - yyp->flags_stack);
		UNSET_ALL(newp);
		SET_JOIN_PENDING(newp);

		bcopy(yyp->pending_join_stack, newp->pending_join_stack, 
		      sizeof newp->pending_join_stack);
		newp->pending_join =
		    newp->pending_join_stack + (yyp->pending_join - 
						yyp->pending_join_stack);
		*newp->pending_join = yyp;
		*yyp->pending_join = newp;

		bcopy(yyp->pending_endif_stack, newp->pending_endif_stack, 
		      sizeof newp->pending_endif_stack);
		newp->pending_endif =
		    newp->pending_endif_stack + (yyp->pending_endif - 
						 yyp->pending_endif_stack);
		*newp->pending_endif = yyp;
		*yyp->pending_endif = newp;

		bcopy(yyp->data_stack, newp->data_stack, sizeof
		      newp->data_stack);
		newp->data = newp->data_stack + (yyp->data - yyp->data_stack);

		if (yyfork)
		    if (yyp->last_reduction)
		    	*yyp->last_reduction =
			   (*yyfork)(yyp->last_reduction,
				     yyp->yychar, yytext, yyppval, 
				     yyp->data, newp->data,
				     currentfile->cpp_skipping);
		    else
			(void)(*yyfork)(yyp->last_reduction,
					yyp->yychar, yytext, yyppval,
					yyp->data, newp->data,
					currentfile->cpp_skipping);

		yyp->cur_token_number = cur_token_number;
		yyp->yychar = YYEMPTY;

		continue;	/* do the next parse */

	    case PPENDIF:
#ifdef YYDEBUG
		if (yydebug)
		    fprintf(errfile, "Next token is ENDIF\n");
#endif
		ap = *yyp->pending_endif;

		if (yyendif) 
		    if (IFDEF_FORK(yyp))
			(*yyendif)(yyp->data, ap->data);
		    else
			(*yyendif)(ap->data, yyp->data);

		notify_of_endif(yyp, ap, &activelist, cur_token_number);
		notify_of_endif(ap, *ap->pending_endif,
		                &activelist, cur_token_number);

		/* all partners are now active and have been notified of
		   the #endif. See if there's anything we can join. */
		merge_active(&activelist, currentfile);

		continue;
		
	    case PPDEFINE:
	    case PPINCLUDE:
	    case PPLINE:
		yyp->yychar = YYEMPTY;
		break;
	    }
	}
	/* This is a real token. Mark this parse has having seen one. */
#ifdef YYDEBUG
	if (yydebug && SEEN_PP_TOKEN(yyp))
	    fprintf(errfile, "Unsetting SEEN_PP_TOKEN for %x, (%s).\n", yyp,
		    *yyp->branch);
#endif
	UNSET_SEEN_PP_TOKEN(yyp);

	/* Convert token to internal form (in yychar1) for indexing
	 * tables with
	 */

	if (yyp->yychar <= 0) { /* This means end of input. */
	    yychar1 = 0;
	    yyp->yychar = YYEOF;	/* Don't call YYLEX any more */

#ifdef YYDEBUG
	    if (yydebug)
		fprintf(errfile, "Now at end of input.\n");
#endif
	} else {
	    yychar1 = YYTRANSLATE(yyp->yychar);

#ifdef YYDEBUG
	    if (yydebug)
		fprintf(errfile, "Next token is %d (%s, %s)\n", yyp->yychar, yytname[yychar1], yytext);
#endif
	}

	yyn += yychar1;
	if (yyn < 0 || yyn > YYLAST || yycheck[yyn] != yychar1)
	    goto yydefault;

	yyn = yytable[yyn];

	/* yyn is what to do for this token type in this state.
	 * Negative => reduce, -yyn is rule number.  	 Positive =>
	 * shift, yyn is new state.  	 New state is final state =>
	 * don't bother to shift, 	 just return success.  	 0, or
	 * most negative number => error.
	 */

	if (yyn < 0) {
	    if (yyn == YYFLAG)
		goto yyerrlab;
	    yyn = -yyn;
	    goto yyreduce;
	} else if (yyn == 0)
	    goto yyerrlab;

	if (yyn == YYFINAL) {
	    _yytext = oldtext;
	    _yylval = oldlval;
	    _yylloc = oldlloc;
	    YYACCEPT;
	}

	/* Shift the lookahead token.  */

#ifdef YYDEBUG
	if (yydebug)
	    fprintf(errfile, "Shifting token %d (%s, %s), ", yyp->yychar, yytname[yychar1], yytext);
#endif

	/* Discard the token being shifted unless it is eof.  */
	if (yyp->yychar != YYEOF) {
	    yyp->yychar = YYEMPTY;
	    *++yyp->yyvsp = yylval;
#ifdef YYLSP_NEEDED
	    ++yyp->yylsp;
	    *yyp->yylsp = yylloc;
#endif
	    SET_JUST_SHIFTED(yyp);
	}

	/* count tokens shifted since error; after three, turn off
	 * error status.
	 */
 	if (yyp->yyerrstatus) yyp->yyerrstatus--;

	yyp->yystate = yyn;
	goto yynewstate;

	/* Do the default action for the current state.  */
    yydefault:
#ifdef YYDEBUG
	if (yydebug) 
	    fprintf(errfile, "yydefault: ");
#endif
	yyn = yydefact[yyp->yystate];
	if (yyn == 0)
	    goto yyerrlab;

	/* Do a reduction.  yyn is the number of a rule to reduce
	 * with.
	 */
    yyreduce:
#ifdef YYDEBUG
	if (yydebug) 
	    fprintf(errfile, "yyreduce: ");
#endif
 	yylen = yyr2[yyn];
	yyval = (yyp->yyvsp)[1-yylen];
	/* implement default value of the action */

#ifdef YYDEBUG
	if (yydebug) {
	    if (yylen == 1)
		fprintf (errfile, "Reducing 1 value via line %d, ",
			 yyrline[yyn]);
	    else
		fprintf (errfile, "Reducing %d values via line %d, ",
			 yylen, yyrline[yyn]);
	}
#endif


$	/* the action file gets copied in in place of this dollarsign */
#line 1120 "bison.simple"

    	yyp->yyvsp -= yylen;
	if (JOIN_PENDING(yyp) && yyp->yyvsp < *yyp->tos_tos)
	    *yyp->tos_tos = yyp->yyvsp;
	*++yyp->yyvsp = yyval;
	if (yylen > 0) {
	    yyp->last_reduction = yyp->yyvsp;
	    UNSET_JUST_SHIFTED(yyp);
	}

	yyp->yyssp -= yylen;
#ifdef YYLSP_NEEDED
	yyp->yylsp -= yylen;
#endif

#ifdef YYDEBUG
	if (yydebug) {
	    short *ssp1 = yyp->yyss - 1;
	    fprintf (errfile, "state stack now");
	    while (ssp1 != yyp->yyssp)
		fprintf (errfile, " %d", *++ssp1);
	    fprintf (errfile, "\n");

	}
#endif

#ifdef YYLSP_NEEDED
	yyp->yylsp++;
	if (yylen == 0)	{
	    yyp->yylsp->first_line = yylloc.first_line;
	    yyp->yylsp->first_column = yylloc.first_column;
	    yyp->yylsp->last_line = (yyp->yylsp-1)->last_line;
	    yyp->yylsp->last_column = (yyp->yylsp-1)->last_column;
	} else {
	    yyp->yylsp->last_line = (yyp->yylsp+yylen-1)->last_line;
	    yyp->yylsp->last_column = (yyp->yylsp+yylen-1)->last_column;
	}
#endif


	/* Now "shift" the result of the reduction. Determine
	 * what state that goes to, based on the state we popped
	 * back to and the rule number reduced by.
	 */

	yyn = yyr1[yyn];

	yyp->yystate = yypgoto[yyn - YYNTBASE] + *yyp->yyssp;
	if (yyp->yystate >= 0 && yyp->yystate <= YYLAST && yycheck[yyp->yystate] == *yyp->yyssp)
	    yyp->yystate = yytable[yyp->yystate];
	else
	    yyp->yystate = yydefgoto[yyn - YYNTBASE];

	yyp->blocked = REDUCTION;
	goto yynewstate;

    yyerrlab:			/* here on detecting error */

	if (! yyp->yyerrstatus) {
	    if (yyp->flink == yyp || !(*yyskip)(yyp->data)) {
		/* If not already recovering from an error,  report this
		   error. */ 
		++yyp->yynerr;
		yyerror(currentfile->as, "parse error");
		if ((yyn = yypact[yyp->yystate]) > YYFLAG && yyn < YYLAST)
		{
		    int x, count;
		    count = 0;
		    for (x = 3; x < (sizeof(yytname) / sizeof(char *)); x++)
		    {
			if (yycheck[x + yyn] == x)
			{
			    fprintf (errfile, "%s %s", 
				     count == 0 ? "expecting:" : " or", 
				     yytname[x]);
			    count++;
			}
		    }
		    fprintf (errfile, "%s", count > 0 ? "\n" : "");
		}
	    }
	    else {
		YYABORT;
	    }
	}

	if (yyp->yyerrstatus == 3) {

	    /* if just tried and failed to reuse lookahead token after
	     * an error, discard it.
	     */

	    /* return failure if at end of input */
	    if (yyp->yychar == YYEOF) {
		_yytext = oldtext;
		_yylval = oldlval;
		_yylloc = oldlloc;
		YYABORT;
	    }

#ifdef YYDEBUG
	    if (yydebug)
		fprintf(errfile, "Discarding token %d (%s).\n", yyp->yychar, yytname[yychar1]);
#endif

	    yyp->yychar = YYEMPTY;
	}

	/* Else will try to reuse lookahead token
	   after shifting the error token.  */

	yyp->yyerrstatus = 3;   /* Each real token shifted decrements this */

	goto yyerrhandle;

    yyerrdefault: 	 

	/* current state does not do anything special for the error
	* token.
	*/

#if 0
	/* This is wrong; only states that explicitly want error
	 * tokens should shift them.
	 */
	yyn = yydefact[yyp->yystate];

	/* If its default is to accept any token, ok.  Otherwise pop
	 * it.
	 */
	if (yyn) goto yydefault;
#endif

    yyerrpop: 	 

	/* pop the current state because it cannot handle the error token */

	if (yyp->yyssp == yyp->yyss)  {
	    _yytext = oldtext;
	    _yylval = oldlval;
	    _yylloc = oldlloc;
	    YYABORT;
	}
	yyp->yyvsp--;
	yyp->yystate = *--yyp->yyssp;
#ifdef YYLSP_NEEDED
	yyp->yylsp--;
#endif

#ifdef YYDEBUG
	if (yydebug) {
	    short *ssp1 = yyp->yyss - 1;
	    fprintf (errfile, "Error: state stack now");
	    while (ssp1 != yyp->yyssp)
		fprintf (errfile, " %d", *++ssp1);
	    fprintf (errfile, "\n");
	}
#endif

    yyerrhandle:

	yyn = yypact[yyp->yystate];
	if (yyn == YYFLAG)
	    goto yyerrdefault;

	yyn += YYTERROR;
	if (yyn < 0 || yyn > YYLAST || yycheck[yyn] != YYTERROR)
	    goto yyerrdefault;

	yyn = yytable[yyn];
	if (yyn < 0) {
	    if (yyn == YYFLAG)
		goto yyerrpop;
	    yyn = -yyn;
	    goto yyreduce;
	} else if (yyn == 0)
	    goto yyerrpop;

	if (yyn == YYFINAL) {
	    _yytext = oldtext;
	    _yylval = oldlval;
	    _yylloc = oldlloc;
	    YYACCEPT;
	}

#ifdef YYDEBUG
	if (yydebug)
	    fprintf(errfile, "Shifting error token, ");
#endif

	*++yyp->yyvsp = yylval;
#ifdef YYLSP_NEEDED
	*++yyp->yylsp = yylloc;
#endif

	yyp->yystate = yyn;
	goto yynewstate;
    yyabort:
	SET_ABORTED(yyp);
#ifdef YYDEBUG
	if (yydebug)
	    fprintf(errfile, "yyabort for parse %x\n", yyp);
#endif
	continue;
    yyaccept: {
	unsigned short *flags;
	
	UNSET_JUST_SHIFTED(yyp); /* Don't care that we just shifted the EOF
				    token. */
	for (flags = yyp->flags; flags >= yyp->flags_stack; flags--) 
	    *flags |= ACCEPTED_BIT;

#ifdef YYDEBUG
	if (yydebug) {
	    short *ssp1 = yyp->yyss - 1;
	    fprintf(errfile, "yyaccept for parse %x\n", yyp);
	    fprintf (errfile, " state stack now");
	    while (ssp1 != yyp->yyssp)
		fprintf (errfile, " %d", *++ssp1);
	    fprintf (errfile, "\n");

	}
#endif
	continue;
    }
	
    } /* end for loop */

    merge_active(&activelist, currentfile);

    _yytext = oldtext;
    _yylval = oldlval;
    _yylloc = oldlloc;
    
    if (yyfinish) 
	yyfinish(activelist->yyvsp, &currentfile->tree_root);
    yyp = activelist;
    retval = ABORTED(activelist) || activelist != activelist->flink;
    do {
	ap = yyp->flink;
	kill_parse(yyp);
	yyp = ap;
    } while (yyp != activelist);
    
    return retval;
    
}