y.tab.c

C语言的语法分析器

case 17:
#line 50 "y.y"
{ fprintf(out, "param -> type_specifer ID[]\n"); ;
    break;}
case 18:
#line 52 "y.y"
{ fprintf(out, "compound_stmt -> {local_declarations statement_list}\n"); ;
    break;}
case 19:
#line 54 "y.y"
{ fprintf(out, "local_declarations -> local_declarations var_declaration\n"); ;
    break;}
case 20:
#line 55 "y.y"
{ fprintf(out, "local_declaration -> $\n"); ;
    break;}
case 21:
#line 57 "y.y"
{ fprintf(out, "statement_list -> statement_list statement\n"); ;
    break;}
case 23:
#line 60 "y.y"
{ fprintf(out, "statement -> expression_stmt\n\n"); ;
    break;}
case 24:
#line 61 "y.y"
{ fprintf(out, "statement -> compound_stmt\n\n"); ;
    break;}
case 25:
#line 62 "y.y"
{ fprintf(out, "statement -> if_stmt\n\n"); ;
    break;}
case 26:
#line 63 "y.y"
{ fprintf(out, "statement -> while_stmt\n\n"); ;
    break;}
case 27:
#line 64 "y.y"
{ fprintf(out, "statement -> return_stmt\n\n"); ;
    break;}
case 28:
#line 66 "y.y"
{ fprintf(out, "expression_stmt -> expression;\n"); ;
    break;}
case 29:
#line 67 "y.y"
{ fprintf(out, "expression_stmt -> ;\n"); ;
    break;}
case 30:
#line 69 "y.y"
{ fprintf(out, "if_stmt -> IF (expression) statement\n"); ;
    break;}
case 31:
#line 70 "y.y"
{ fprintf(out, "if_stmt -> IF (expression) statement ELSE statement\n"); ;
    break;}
case 32:
#line 72 "y.y"
{ fprintf(out, "WHILE (expression) statement\n"); ;
    break;}
case 33:
#line 74 "y.y"
{ fprintf(out, "RETURN;\n"); ;
    break;}
case 34:
#line 75 "y.y"
{ fprintf(out, "RETURN expression;\n"); ;
    break;}
case 35:
#line 77 "y.y"
{ fprintf(out, "expression -> var = expression\n"); ;
    break;}
case 36:
#line 78 "y.y"
{ fprintf(out, "expression -> simple_expression\n"); ;
    break;}
case 37:
#line 80 "y.y"
{ fprintf(out, "var -> ID\n"); ;
    break;}
case 38:
#line 81 "y.y"
{ fprintf(out, "var -> ID[expression]\n"); ;
    break;}
case 39:
#line 83 "y.y"
{ fprintf(out, "simple_expression -> additive_expression relop additive_expression\n"); ;
    break;}
case 40:
#line 84 "y.y"
{ fprintf(out, "simple_expression -> additive_expression\n"); ;
    break;}
case 41:
#line 86 "y.y"
{ fprintf(out, "additive_expression -> additive_expression addop term\n"); ;
    break;}
case 42:
#line 87 "y.y"
{ fprintf(out, "additive_expression -> term\n"); ;
    break;}
case 43:
#line 89 "y.y"
{ fprintf(out, "addop -> +\n"); ;
    break;}
case 44:
#line 90 "y.y"
{ fprintf(out, "addop -> -\n"); ;
    break;}
case 45:
#line 92 "y.y"
{ fprintf(out, "term -> term mulop factor\n"); ;
    break;}
case 46:
#line 93 "y.y"
{ fprintf(out, "term -> factor\n"); ;
    break;}
case 47:
#line 95 "y.y"
{ fprintf(out, "mulop -> *\n"); ;
    break;}
case 48:
#line 96 "y.y"
{ fprintf(out, "mulop -> /\n"); ;
    break;}
case 49:
#line 98 "y.y"
{ fprintf(out, "factor -> (expression)\n"); ;
    break;}
case 50:
#line 99 "y.y"
{ fprintf(out, "factor -> var\n"); ;
    break;}
case 51:
#line 100 "y.y"
{ fprintf(out, "facotr -> call\n"); ;
    break;}
case 52:
#line 101 "y.y"
{ fprintf(out, "factor -> NUMBER\n"); ;
    break;}
case 53:
#line 103 "y.y"
{ fprintf(out, "call -> ID (args)\n"); ;
    break;}
case 54:
#line 105 "y.y"
{ fprintf(out, "args -> arg_list\n"); ;
    break;}
case 55:
#line 106 "y.y"
{ fprintf(out, "args -> $\n"); ;
    break;}
case 56:
#line 108 "y.y"
{ fprintf(out, "arg_list -> arg_list, expression\n"); ;
    break;}
case 57:
#line 109 "y.y"
{ fprintf(out, "arg_list expression\n"); ;
    break;}
}
   /* the action file gets copied in in place of this dollarsign */
#line 543 "/usr/local/share/bison.simple"

  yyvsp -= yylen;
  yyssp -= yylen;
#ifdef YYLSP_NEEDED
  yylsp -= yylen;
#endif

#if YYDEBUG != 0
  if (yydebug)
    {
      short *ssp1 = yyss - 1;
      fprintf (stderr, "state stack now");
      while (ssp1 != yyssp)
	fprintf (stderr, " %d", *++ssp1);
      fprintf (stderr, "\n");
    }
#endif

  *++yyvsp = yyval;

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

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

  goto yynewstate;

yyerrlab:   /* here on detecting error */

  if (! yyerrstatus)
    /* If not already recovering from an error, report this error.  */
    {
      ++yynerrs;

#ifdef YYERROR_VERBOSE
      yyn = yypact[yystate];

      if (yyn > YYFLAG && yyn < YYLAST)
	{
	  int size = 0;
	  char *msg;
	  int x, count;

	  count = 0;
	  /* Start X at -yyn if nec to avoid negative indexes in yycheck.  */
	  for (x = (yyn < 0 ? -yyn : 0);
	       x < (sizeof(yytname) / sizeof(char *)); x++)
	    if (yycheck[x + yyn] == x)
	      size += strlen(yytname[x]) + 15, count++;
	  msg = (char *) malloc(size + 15);
	  if (msg != 0)
	    {
	      strcpy(msg, "parse error");

	      if (count < 5)
		{
		  count = 0;
		  for (x = (yyn < 0 ? -yyn : 0);
		       x < (sizeof(yytname) / sizeof(char *)); x++)
		    if (yycheck[x + yyn] == x)
		      {
			strcat(msg, count == 0 ? ", expecting `" : " or `");
			strcat(msg, yytname[x]);
			strcat(msg, "'");
			count++;
		      }
		}
	      yyerror(msg);
	      free(msg);
	    }
	  else
	    yyerror ("parse error; also virtual memory exceeded");
	}
      else
#endif /* YYERROR_VERBOSE */
	yyerror("parse error");
    }

  goto yyerrlab1;
yyerrlab1:   /* here on error raised explicitly by an action */

  if (yyerrstatus == 3)
    {
      /* if just tried and failed to reuse lookahead token after an error, discard it.  */

      /* return failure if at end of input */
      if (yychar == YYEOF)
	YYABORT;

#if YYDEBUG != 0
      if (yydebug)
	fprintf(stderr, "Discarding token %d (%s).\n", yychar, yytname[yychar1]);
#endif

      yychar = YYEMPTY;
    }

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

  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[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 (yyssp == yyss) YYABORT;
  yyvsp--;
  yystate = *--yyssp;
#ifdef YYLSP_NEEDED
  yylsp--;
#endif

#if YYDEBUG != 0
  if (yydebug)
    {
      short *ssp1 = yyss - 1;
      fprintf (stderr, "Error: state stack now");
      while (ssp1 != yyssp)
	fprintf (stderr, " %d", *++ssp1);
      fprintf (stderr, "\n");
    }
#endif

yyerrhandle:

  yyn = yypact[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)
    YYACCEPT;

#if YYDEBUG != 0
  if (yydebug)
    fprintf(stderr, "Shifting error token, ");
#endif

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

  yystate = yyn;
  goto yynewstate;

 yyacceptlab:
  /* YYACCEPT comes here.  */
  if (yyfree_stacks)
    {
      free (yyss);
      free (yyvs);
#ifdef YYLSP_NEEDED
      free (yyls);
#endif
    }
  return 0;

 yyabortlab:
  /* YYABORT comes here.  */
  if (yyfree_stacks)
    {
      free (yyss);
      free (yyvs);
#ifdef YYLSP_NEEDED
      free (yyls);
#endif
    }
  return 1;
}
#line 112 "y.y"


void yyerror(const char *msg)
{
	fprintf(out, "ERROR: %s\n", msg);
}


int main(int argc, char *argv[])
{
	if (argc > 2)
	{
		yyin = fopen(argv[1], "r");
		if (!yyin)
		{
			fprintf(stderr, "Can not open %s\n", argv[1]);
			exit(1);
		}
		out = fopen(argv[2], "w");
		if (!out)
		{
			fprintf(stderr, "Can not open %s\n", argv[2]);
			exit(1);
		}
		yyparse();
		fclose(yyin);
		fclose(out);
	}

	return 0;
}