bison.simple

对pl0语言程序的语法分析源程序

/* -*-C-*-  Note some compilers choke on comments on `#line' lines.  */
#line
/* Skeleton output parser for bison,

   Copyright (C) 1984, 1989, 1990, 2000, 2001, 2002 Free Software
   Foundation, Inc.

   This program 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.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/* As a special exception, when this file is copied by Bison into a
   Bison output file, you may use that output file without restriction.
   This special exception was added by the Free Software Foundation
   in version 1.24 of Bison.  */

/* 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.  */

/* All symbols defined below should begin with yy or YY, to avoid
   infringing on user name space.  This should be done even for local
   variables, as they might otherwise be expanded by user macros.
   There are some unavoidable exceptions within include files to
   define necessary library symbols; they are noted "INFRINGES ON
   USER NAME SPACE" below.  */

#if ! defined (yyoverflow) || defined (YYERROR_VERBOSE)

/* The parser invokes alloca or malloc; define the necessary symbols.  */

# if YYSTACK_USE_ALLOCA
#  define YYSTACK_ALLOC alloca
# else
#  ifndef YYSTACK_USE_ALLOCA
#   if defined (alloca) || defined (_ALLOCA_H)
#    define YYSTACK_ALLOC alloca
#   else
#    ifdef __GNUC__
#     define YYSTACK_ALLOC __builtin_alloca
#    endif
#   endif
#  endif
# endif

# ifdef YYSTACK_ALLOC
   /* Pacify GCC's `empty if-body' warning. */
#  define YYSTACK_FREE(Ptr) do { /* empty */; } while (0)
# else
#  if defined (__STDC__) || defined (__cplusplus)
#   include <stdlib.h> /* INFRINGES ON USER NAME SPACE */
#   define YYSIZE_T size_t
#  endif
#  define YYSTACK_ALLOC malloc
#  define YYSTACK_FREE free
# endif
#endif /* ! defined (yyoverflow) || defined (YYERROR_VERBOSE) */


#if (! defined (yyoverflow) \
     && (! defined (__cplusplus) \
	 || (YYLTYPE_IS_TRIVIAL && YYSTYPE_IS_TRIVIAL)))

/* A type that is properly aligned for any stack member.  */
union yyalloc
{
  short yyss;
  YYSTYPE yyvs;
# if YYLSP_NEEDED
  YYLTYPE yyls;
# endif
};

/* The size of the maximum gap between one aligned stack and the next.  */
# define YYSTACK_GAP_MAX (sizeof (union yyalloc) - 1)

/* The size of an array large to enough to hold all stacks, each with
   N elements.  */
# if YYLSP_NEEDED
#  define YYSTACK_BYTES(N) \
     ((N) * (sizeof (short) + sizeof (YYSTYPE) + sizeof (YYLTYPE))	\
      + 2 * YYSTACK_GAP_MAX)
# else
#  define YYSTACK_BYTES(N) \
     ((N) * (sizeof (short) + sizeof (YYSTYPE))				\
      + YYSTACK_GAP_MAX)
# endif

/* Copy COUNT objects from FROM to TO.  The source and destination do
   not overlap.  */
# ifndef YYCOPY
#  if 1 < __GNUC__
#   define YYCOPY(To, From, Count) \
      __builtin_memcpy (To, From, (Count) * sizeof (*(From)))
#  else
#   define YYCOPY(To, From, Count)		\
      do					\
	{					\
	  register YYSIZE_T yyi;		\
	  for (yyi = 0; yyi < (Count); yyi++)	\
	    (To)[yyi] = (From)[yyi];		\
	}					\
      while (0)
#  endif
# endif

/* Relocate STACK from its old location to the new one.  The
   local variables YYSIZE and YYSTACKSIZE give the old and new number of
   elements in the stack, and YYPTR gives the new location of the
   stack.  Advance YYPTR to a properly aligned location for the next
   stack.  */
# define YYSTACK_RELOCATE(Stack)					\
    do									\
      {									\
	YYSIZE_T yynewbytes;						\
	YYCOPY (&yyptr->Stack, Stack, yysize);				\
	Stack = &yyptr->Stack;						\
	yynewbytes = yystacksize * sizeof (*Stack) + YYSTACK_GAP_MAX;	\
	yyptr += yynewbytes / sizeof (*yyptr);				\
      }									\
    while (0)

#endif


#if ! defined (YYSIZE_T) && defined (__SIZE_TYPE__)
# define YYSIZE_T __SIZE_TYPE__
#endif
#if ! defined (YYSIZE_T) && defined (size_t)
# define YYSIZE_T size_t
#endif
#if ! defined (YYSIZE_T)
# if defined (__STDC__) || defined (__cplusplus)
#  include <stddef.h> /* INFRINGES ON USER NAME SPACE */
#  define YYSIZE_T size_t
# endif
#endif
#if ! defined (YYSIZE_T)
# define YYSIZE_T unsigned int
#endif

#define yyerrok		(yyerrstatus = 0)
#define yyclearin	(yychar = YYEMPTY)
#define YYEMPTY		-2
#define YYEOF		0
#define YYACCEPT	goto yyacceptlab
#define YYABORT 	goto yyabortlab
#define YYERROR		goto yyerrlab1
/* Like YYERROR except do call yyerror.  This remains here temporarily
   to ease the transition to the new meaning of YYERROR, for GCC.
   Once GCC version 2 has supplanted version 1, this can go.  */
#define YYFAIL		goto yyerrlab
#define YYRECOVERING()  (!!yyerrstatus)
#define YYBACKUP(Token, Value)					\
do								\
  if (yychar == YYEMPTY && yylen == 1)				\
    {								\
      yychar = (Token);						\
      yylval = (Value);						\
      yychar1 = YYTRANSLATE (yychar);				\
      YYPOPSTACK;						\
      goto yybackup;						\
    }								\
  else								\
    { 								\
      yyerror ("syntax error: cannot back up");			\
      YYERROR;							\
    }								\
while (0)

#define YYTERROR	1
#define YYERRCODE	256


/* YYLLOC_DEFAULT -- Compute the default location (before the actions
   are run).

   When YYLLOC_DEFAULT is run, CURRENT is set the location of the
   first token.  By default, to implement support for ranges, extend
   its range to the last symbol.  */

#ifndef YYLLOC_DEFAULT
# define YYLLOC_DEFAULT(Current, Rhs, N)       	\
   Current.last_line   = Rhs[N].last_line;	\
   Current.last_column = Rhs[N].last_column;
#endif


/* YYLEX -- calling `yylex' with the right arguments.  */

#if YYPURE
# if YYLSP_NEEDED
#  ifdef YYLEX_PARAM
#   define YYLEX		yylex (&yylval, &yylloc, YYLEX_PARAM)
#  else
#   define YYLEX		yylex (&yylval, &yylloc)
#  endif
# else /* !YYLSP_NEEDED */
#  ifdef YYLEX_PARAM
#   define YYLEX		yylex (&yylval, YYLEX_PARAM)
#  else
#   define YYLEX		yylex (&yylval)
#  endif
# endif /* !YYLSP_NEEDED */
#else /* !YYPURE */
# define YYLEX			yylex ()
#endif /* !YYPURE */


/* Enable debugging if requested.  */
#if YYDEBUG

# ifndef YYFPRINTF
#  include <stdio.h> /* INFRINGES ON USER NAME SPACE */
#  define YYFPRINTF fprintf
# endif

# define YYDPRINTF(Args)			\
do {						\
  if (yydebug)					\
    YYFPRINTF Args;				\
} while (0)
/* Nonzero means print parse trace.  It is left uninitialized so that
   multiple parsers can coexist.  */
int yydebug;
#else /* !YYDEBUG */
# define YYDPRINTF(Args)
#endif /* !YYDEBUG */

/* YYINITDEPTH -- initial size of the parser's stacks.  */
#ifndef	YYINITDEPTH
# define YYINITDEPTH 200
#endif

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

   Do not make this value too large; the results are undefined if
   SIZE_MAX < YYSTACK_BYTES (YYMAXDEPTH)
   evaluated with infinite-precision integer arithmetic.  */

#if YYMAXDEPTH == 0
# undef YYMAXDEPTH
#endif

#ifndef YYMAXDEPTH
# define YYMAXDEPTH 10000
#endif

#ifdef YYERROR_VERBOSE

# ifndef yystrlen
#  if defined (__GLIBC__) && defined (_STRING_H)
#   define yystrlen strlen
#  else
/* Return the length of YYSTR.  */
static YYSIZE_T
#   if defined (__STDC__) || defined (__cplusplus)
yystrlen (const char *yystr)
#   else
yystrlen (yystr)
     const char *yystr;
#   endif
{
  register const char *yys = yystr;

  while (*yys++ != '\0')
    continue;

  return yys - yystr - 1;
}
#  endif
# endif

# ifndef yystpcpy
#  if defined (__GLIBC__) && defined (_STRING_H) && defined (_GNU_SOURCE)
#   define yystpcpy stpcpy
#  else
/* Copy YYSRC to YYDEST, returning the address of the terminating '\0' in
   YYDEST.  */
static char *
#   if defined (__STDC__) || defined (__cplusplus)
yystpcpy (char *yydest, const char *yysrc)
#   else
yystpcpy (yydest, yysrc)
     char *yydest;
     const char *yysrc;
#   endif
{
  register char *yyd = yydest;
  register const char *yys = yysrc;

  while ((*yyd++ = *yys++) != '\0')
    continue;

  return yyd - 1;
}
#  endif
# endif
#endif

#line

/* The user can define YYPARSE_PARAM as the name of an argument to be passed
   into yyparse.  The argument should have type void *.
   It should actually point to an object.
   Grammar actions can access the variable by casting it
   to the proper pointer type.  */

#ifdef YYPARSE_PARAM
# if defined (__STDC__) || defined (__cplusplus)
#  define YYPARSE_PARAM_ARG void *YYPARSE_PARAM
#  define YYPARSE_PARAM_DECL
# else
#  define YYPARSE_PARAM_ARG YYPARSE_PARAM
#  define YYPARSE_PARAM_DECL void *YYPARSE_PARAM;
# endif
#else /* !YYPARSE_PARAM */
# define YYPARSE_PARAM_ARG
# define YYPARSE_PARAM_DECL
#endif /* !YYPARSE_PARAM */

/* Prevent warning if -Wstrict-prototypes.  */
#ifdef __GNUC__
# ifdef YYPARSE_PARAM
int yyparse (void *);
# else
int yyparse (void);
# endif
#endif

/* YY_DECL_VARIABLES -- depending whether we use a pure parser,
   variables are global, or local to YYPARSE.  */

#define YY_DECL_NON_LSP_VARIABLES			\
/* The lookahead symbol.  */				\
int yychar;						\
							\
/* The semantic value of the lookahead symbol. */	\
YYSTYPE yylval;						\
							\
/* Number of parse errors so far.  */			\
int yynerrs;

#if YYLSP_NEEDED
# define YY_DECL_VARIABLES			\
YY_DECL_NON_LSP_VARIABLES			\
						\
/* Location data for the lookahead symbol.  */	\
YYLTYPE yylloc;
#else
# define YY_DECL_VARIABLES			\
YY_DECL_NON_LSP_VARIABLES
#endif


/* If nonreentrant, generate the variables here. */

#if !YYPURE
YY_DECL_VARIABLES
#endif  /* !YYPURE */

int
yyparse (YYPARSE_PARAM_ARG)
     YYPARSE_PARAM_DECL
{
  /* If reentrant, generate the variables here. */
#if YYPURE
  YY_DECL_VARIABLES
#endif  /* !YYPURE */

  register int yystate;
  register int yyn;
  int yyresult;
  /* Number of tokens to shift before error messages enabled.  */
  int yyerrstatus;
  /* Lookahead token as an internal (translated) token number.  */
  int yychar1 = 0;

  /* Three stacks and their tools:
     `yyss': related to states,
     `yyvs': related to semantic values,
     `yyls': related to locations.

     Refer to the stacks thru separate pointers, to allow yyoverflow
     to reallocate them elsewhere.  */

  /* The state stack. */
  short	yyssa[YYINITDEPTH];
  short *yyss = yyssa;
  register short *yyssp;

  /* The semantic value stack.  */
  YYSTYPE yyvsa[YYINITDEPTH];
  YYSTYPE *yyvs = yyvsa;
  register YYSTYPE *yyvsp;

#if YYLSP_NEEDED
  /* The location stack.  */
  YYLTYPE yylsa[YYINITDEPTH];
  YYLTYPE *yyls = yylsa;
  YYLTYPE *yylsp;
#endif

#if YYLSP_NEEDED
# define YYPOPSTACK   (yyvsp--, yyssp--, yylsp--)
#else
# define YYPOPSTACK   (yyvsp--, yyssp--)
#endif

  YYSIZE_T yystacksize = YYINITDEPTH;


  /* The variables used to return semantic value and location from the
     action routines.  */
  YYSTYPE yyval;
#if YYLSP_NEEDED
  YYLTYPE yyloc;
#endif

  /* When reducing, the number of symbols on the RHS of the reduced
     rule. */
  int yylen;

  YYDPRINTF ((stderr, "Starting parse\n"));

  yystate = 0;
  yyerrstatus = 0;
  yynerrs = 0;
  yychar = YYEMPTY;		/* Cause a token to be read.  */

  /* Initialize stack pointers.
     Waste one element of value and location stack
     so that they stay on the same level as the state stack.
     The wasted elements are never initialized.  */

  yyssp = yyss;
  yyvsp = yyvs;
#if YYLSP_NEEDED
  yylsp = yyls;
#endif
  goto yysetstate;

/*------------------------------------------------------------.
| yynewstate -- Push a new state, which is found in yystate.  |
`------------------------------------------------------------*/
 yynewstate:
  /* In all cases, when you get here, the value and location stacks
     have just been pushed. so pushing a state here evens the stacks.
     */
  yyssp++;

 yysetstate:
  *yyssp = yystate;