bc.c

操作系统源代码

"$$7 :",
"statement : While $$6 '(' expression $$7 ')' statement",
"statement : '{' statement_list '}'",
"$$8 :",
"statement : Print $$8 print_list",
"print_list : print_element",
"print_list : print_element ',' print_list",
"print_element : STRING",
"print_element : expression",
"opt_else :",
"$$9 :",
"opt_else : Else $$9 statement",
"$$10 :",
"function : Define NAME '(' opt_parameter_list ')' '{' NEWLINE opt_auto_define_list $$10 statement_list NEWLINE '}'",
"opt_parameter_list :",
"opt_parameter_list : define_list",
"opt_auto_define_list :",
"opt_auto_define_list : Auto define_list NEWLINE",
"opt_auto_define_list : Auto define_list ';'",
"define_list : NAME",
"define_list : NAME '[' ']'",
"define_list : define_list ',' NAME",
"define_list : define_list ',' NAME '[' ']'",
"opt_argument_list :",
"opt_argument_list : argument_list",
"argument_list : expression",
"argument_list : NAME '[' ']'",
"argument_list : argument_list ',' expression",
"argument_list : argument_list ',' NAME '[' ']'",
"opt_expression :",
"opt_expression : expression",
"return_expression :",
"return_expression : expression",
"$$11 :",
"expression : named_expression ASSIGN_OP $$11 expression",
"$$12 :",
"expression : expression AND $$12 expression",
"$$13 :",
"expression : expression OR $$13 expression",
"expression : NOT expression",
"expression : expression REL_OP expression",
"expression : expression '+' expression",
"expression : expression '-' expression",
"expression : expression MUL_OP expression",
"expression : expression '^' expression",
"expression : '-' expression",
"expression : named_expression",
"expression : NUMBER",
"expression : '(' expression ')'",
"expression : NAME '(' opt_argument_list ')'",
"expression : INCR_DECR named_expression",
"expression : named_expression INCR_DECR",
"expression : Length '(' expression ')'",
"expression : Sqrt '(' expression ')'",
"expression : Scale '(' expression ')'",
"expression : Read '(' ')'",
"named_expression : NAME",
"named_expression : NAME '[' expression ']'",
"named_expression : Ibase",
"named_expression : Obase",
"named_expression : Scale",
"named_expression : Last",
};
#endif
#define yyclearin (yychar=(-1))
#define yyerrok (yyerrflag=0)
#ifdef YYSTACKSIZE
#ifndef YYMAXDEPTH
#define YYMAXDEPTH YYSTACKSIZE
#endif
#else
#ifdef YYMAXDEPTH
#define YYSTACKSIZE YYMAXDEPTH
#else
#define YYSTACKSIZE 500
#define YYMAXDEPTH 500
#endif
#endif
int yydebug;
int yynerrs;
int yyerrflag;
int yychar;
short *yyssp;
YYSTYPE *yyvsp;
YYSTYPE yyval;
YYSTYPE yylval;
short yyss[YYSTACKSIZE];
YYSTYPE yyvs[YYSTACKSIZE];
#define yystacksize YYSTACKSIZE
#define YYABORT goto yyabort
#define YYACCEPT goto yyaccept
#define YYERROR goto yyerrlab
int
yyparse()
{
    register int yym, yyn, yystate;
#if YYDEBUG
    register char *yys;
    extern char *getenv();

    if (yys = getenv("YYDEBUG"))
    {
        yyn = *yys;
        if (yyn >= '0' && yyn <= '9')
            yydebug = yyn - '0';
    }
#endif

    yynerrs = 0;
    yyerrflag = 0;
    yychar = (-1);

    yyssp = yyss;
    yyvsp = yyvs;
    *yyssp = yystate = 0;

yyloop:
    if (yyn = yydefred[yystate]) goto yyreduce;
    if (yychar < 0)
    {
        if ((yychar = yylex()) < 0) yychar = 0;
#if YYDEBUG
        if (yydebug)
        {
            yys = 0;
            if (yychar <= YYMAXTOKEN) yys = yyname[yychar];
            if (!yys) yys = "illegal-symbol";
            printf("yydebug: state %d, reading %d (%s)\n", yystate,
                    yychar, yys);
        }
#endif
    }
    if ((yyn = yysindex[yystate]) && (yyn += yychar) >= 0 &&
            yyn <= YYTABLESIZE && yycheck[yyn] == yychar)
    {
#if YYDEBUG
        if (yydebug)
            printf("yydebug: state %d, shifting to state %d\n",
                    yystate, yytable[yyn]);
#endif
        if (yyssp >= yyss + yystacksize - 1)
        {
            goto yyoverflow;
        }
        *++yyssp = yystate = yytable[yyn];
        *++yyvsp = yylval;
        yychar = (-1);
        if (yyerrflag > 0)  --yyerrflag;
        goto yyloop;
    }
    if ((yyn = yyrindex[yystate]) && (yyn += yychar) >= 0 &&
            yyn <= YYTABLESIZE && yycheck[yyn] == yychar)
    {
        yyn = yytable[yyn];
        goto yyreduce;
    }
    if (yyerrflag) goto yyinrecovery;
#ifdef lint
    goto yynewerror;
#endif
yynewerror:
    yyerror("syntax error");
#ifdef lint
    goto yyerrlab;
#endif
yyerrlab:
    ++yynerrs;
yyinrecovery:
    if (yyerrflag < 3)
    {
        yyerrflag = 3;
        for (;;)
        {
            if ((yyn = yysindex[*yyssp]) && (yyn += YYERRCODE) >= 0 &&
                    yyn <= YYTABLESIZE && yycheck[yyn] == YYERRCODE)
            {
#if YYDEBUG
                if (yydebug)
                    printf("yydebug: state %d, error recovery shifting\
 to state %d\n", *yyssp, yytable[yyn]);
#endif
                if (yyssp >= yyss + yystacksize - 1)
                {
                    goto yyoverflow;
                }
                *++yyssp = yystate = yytable[yyn];
                *++yyvsp = yylval;
                goto yyloop;
            }
            else
            {
#if YYDEBUG
                if (yydebug)
                    printf("yydebug: error recovery discarding state %d\n",
                            *yyssp);
#endif
                if (yyssp <= yyss) goto yyabort;
                --yyssp;
                --yyvsp;
            }
        }
    }
    else
    {
        if (yychar == 0) goto yyabort;
#if YYDEBUG
        if (yydebug)
        {
            yys = 0;
            if (yychar <= YYMAXTOKEN) yys = yyname[yychar];
            if (!yys) yys = "illegal-symbol";
            printf("yydebug: state %d, error recovery discards token %d (%s)\n",
                    yystate, yychar, yys);
        }
#endif
        yychar = (-1);
        goto yyloop;
    }
yyreduce:
#if YYDEBUG
    if (yydebug)
        printf("yydebug: state %d, reducing by rule %d (%s)\n",
                yystate, yyn, yyrule[yyn]);
#endif
    yym = yylen[yyn];
    yyval = yyvsp[1-yym];
    switch (yyn)
    {
case 1:
#line 106 "bc.y"
{
			      yyval.i_value = 0;
			      if (interactive)
				{
				  printf ("%s\n", BC_VERSION);
				  welcome ();
				}
			    }
break;
case 3:
#line 117 "bc.y"
{ run_code (); }
break;
case 4:
#line 119 "bc.y"
{ run_code (); }
break;
case 5:
#line 121 "bc.y"
{
			      yyerrok;
			      init_gen ();
			    }
break;
case 6:
#line 127 "bc.y"
{ yyval.i_value = 0; }
break;
case 10:
#line 133 "bc.y"
{ yyval.i_value = 0; }
break;
case 17:
#line 142 "bc.y"
{ yyval.i_value = yyvsp[0].i_value; }
break;
case 18:
#line 145 "bc.y"
{ warranty (""); }
break;
case 19:
#line 147 "bc.y"
{ limits (); }
break;
case 20:
#line 149 "bc.y"
{
			      if (yyvsp[0].i_value & 2)
				warn ("comparison in expression");
			      if (yyvsp[0].i_value & 1)
				generate ("W");
			      else 
				generate ("p");
			    }
break;
case 21:
#line 158 "bc.y"
{
			      yyval.i_value = 0;
			      generate ("w");
			      generate (yyvsp[0].s_value);
			      free (yyvsp[0].s_value);
			    }
break;
case 22:
#line 165 "bc.y"
{
			      if (break_label == 0)
				yyerror ("Break outside a for/while");
			      else
				{
				  sprintf (genstr, "J%1d:", break_label);
				  generate (genstr);
				}
			    }
break;
case 23:
#line 175 "bc.y"
{
			      warn ("Continue statement");
			      if (continue_label == 0)
				yyerror ("Continue outside a for");
			      else
				{
				  sprintf (genstr, "J%1d:", continue_label);
				  generate (genstr);
				}
			    }
break;
case 24:
#line 186 "bc.y"
{ exit (0); }
break;
case 25:
#line 188 "bc.y"
{ generate ("h"); }
break;
case 26:
#line 190 "bc.y"
{ generate ("0R"); }
break;
case 27:
#line 192 "bc.y"
{ generate ("R"); }
break;
case 28:
#line 194 "bc.y"
{
			      yyvsp[0].i_value = break_label; 
			      break_label = next_label++;
			    }
break;
case 29:
#line 199 "bc.y"
{
			      if (yyvsp[-1].i_value > 1)
				warn ("Comparison in first for expression");
			      yyvsp[-1].i_value = next_label++;
			      if (yyvsp[-1].i_value < 0)
				sprintf (genstr, "N%1d:", yyvsp[-1].i_value);
			      else
				sprintf (genstr, "pN%1d:", yyvsp[-1].i_value);
			      generate (genstr);
			    }
break;
case 30:
#line 210 "bc.y"
{
			      if (yyvsp[-1].i_value < 0) generate ("1");
			      yyvsp[-1].i_value = next_label++;
			      sprintf (genstr, "B%1d:J%1d:", yyvsp[-1].i_value, break_label);
			      generate (genstr);
			      yyval.i_value = continue_label;
			      continue_label = next_label++;
			      sprintf (genstr, "N%1d:", continue_label);
			      generate (genstr);
			    }
break;
case 31:
#line 221 "bc.y"
{
			      if (yyvsp[-1].i_value > 1)
				warn ("Comparison in third for expression");
			      if (yyvsp[-1].i_value < 0)
				sprintf (genstr, "J%1d:N%1d:", yyvsp[-7].i_value, yyvsp[-4].i_value);
			      else
				sprintf (genstr, "pJ%1d:N%1d:", yyvsp[-7].i_value, yyvsp[-4].i_value);
			      generate (genstr);
			    }
break;
case 32:
#line 231 "bc.y"
{
			      sprintf (genstr, "J%1d:N%1d:",
				       continue_label, break_label);
			      generate (genstr);
			      break_label = yyvsp[-12].i_value;
			      continue_label = yyvsp[-4].i_value;
			    }
break;
case 33:
#line 239 "bc.y"
{
			      yyvsp[-1].i_value = if_label;
			      if_label = next_label++;
			      sprintf (genstr, "Z%1d:", if_label);
			      generate (genstr);
			    }
break;
case 34:
#line 246 "bc.y"
{
			      sprintf (genstr, "N%1d:", if_label); 
			      generate (genstr);
			      if_label = yyvsp[-4].i_value;
			    }
break;
case 35:
#line 252 "bc.y"
{
			      yyvsp[0].i_value = next_label++;
			      sprintf (genstr, "N%1d:", yyvsp[0].i_value);
			      generate (genstr);
			    }
break;
case 36:
#line 258 "bc.y"
{
			      yyvsp[0].i_value = break_label; 
			      break_label = next_label++;
			      sprintf (genstr, "Z%1d:", break_label);
			      generate (genstr);
			    }
break;
case 37:
#line 265 "bc.y"
{
			      sprintf (genstr, "J%1d:N%1d:", yyvsp[-6].i_value, break_label);
			      generate (genstr);
			      break_label = yyvsp[-3].i_value;
			    }
break;
case 38:
#line 271 "bc.y"
{ yyval.i_value = 0; }
break;
case 39:
#line 273 "bc.y"
{  warn ("print statement"); }
break;
case 43:
#line 280 "bc.y"
{
			      generate ("O");
			      generate (yyvsp[0].s_value);
			      free (yyvsp[0].s_value);
			    }
break;
case 44:
#line 286 "bc.y"
{ generate ("P"); }
break;
case 46:
#line 290 "bc.y"
{
			      warn ("else clause in if statement");
			      yyvsp[0].i_value = next_label++;