parser.c

cg编译器

#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;

  if (yyssp >= yyss + yystacksize - 1)
    {
      /* Get the current used size of the three stacks, in elements.  */
      YYSIZE_T yysize = yyssp - yyss + 1;

#ifdef yyoverflow
      {
	/* Give user a chance to reallocate the stack. Use copies of
	   these so that the &'s don't force the real ones into
	   memory.  */
	YYSTYPE *yyvs1 = yyvs;
	short *yyss1 = yyss;

	/* Each stack pointer address is followed by the size of the
	   data in use in that stack, in bytes.  */
# if YYLSP_NEEDED
	YYLTYPE *yyls1 = yyls;
	/* This used to be a conditional around just the two extra args,
	   but that might be undefined if yyoverflow is a macro.  */
	yyoverflow ("parser stack overflow",
		    &yyss1, yysize * sizeof (*yyssp),
		    &yyvs1, yysize * sizeof (*yyvsp),
		    &yyls1, yysize * sizeof (*yylsp),
		    &yystacksize);
	yyls = yyls1;
# else
	yyoverflow ("parser stack overflow",
		    &yyss1, yysize * sizeof (*yyssp),
		    &yyvs1, yysize * sizeof (*yyvsp),
		    &yystacksize);
# endif
	yyss = yyss1;
	yyvs = yyvs1;
      }
#else /* no yyoverflow */
# ifndef YYSTACK_RELOCATE
      goto yyoverflowlab;
# else
      /* Extend the stack our own way.  */
      if (yystacksize >= YYMAXDEPTH)
	goto yyoverflowlab;
      yystacksize *= 2;
      if (yystacksize > YYMAXDEPTH)
	yystacksize = YYMAXDEPTH;

      {
	short *yyss1 = yyss;
	union yyalloc *yyptr =
	  (union yyalloc *) YYSTACK_ALLOC (YYSTACK_BYTES (yystacksize));
	if (! yyptr)
	  goto yyoverflowlab;
	YYSTACK_RELOCATE (yyss);
	YYSTACK_RELOCATE (yyvs);
# if YYLSP_NEEDED
	YYSTACK_RELOCATE (yyls);
# endif
# undef YYSTACK_RELOCATE
	if (yyss1 != yyssa)
	  YYSTACK_FREE (yyss1);
      }
# endif
#endif /* no yyoverflow */

      yyssp = yyss + yysize - 1;
      yyvsp = yyvs + yysize - 1;
#if YYLSP_NEEDED
      yylsp = yyls + yysize - 1;
#endif

      YYDPRINTF ((stderr, "Stack size increased to %lu\n",
		  (unsigned long int) yystacksize));

      if (yyssp >= yyss + yystacksize - 1)
	YYABORT;
    }

  YYDPRINTF ((stderr, "Entering state %d\n", yystate));

  goto yybackup;


/*-----------.
| yybackup.  |
`-----------*/
yybackup:

/* Do appropriate processing given the current state.  */
/* Read a lookahead token if we need one and don't already have one.  */
/* yyresume: */

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

  yyn = yypact[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 (yychar == YYEMPTY)
    {
      YYDPRINTF ((stderr, "Reading a token: "));
      yychar = YYLEX;
    }

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

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

      YYDPRINTF ((stderr, "Now at end of input.\n"));
    }
  else
    {
      yychar1 = YYTRANSLATE (yychar);

#if YYDEBUG
     /* We have to keep this `#if YYDEBUG', since we use variables
	which are defined only if `YYDEBUG' is set.  */
      if (yydebug)
	{
	  YYFPRINTF (stderr, "Next token is %d (%s",
		     yychar, yytname[yychar1]);
	  /* Give the individual parser a way to print the precise
	     meaning of a token, for further debugging info.  */
# ifdef YYPRINT
	  YYPRINT (stderr, yychar, yylval);
# endif
	  YYFPRINTF (st