Разработка программы-компилятора

Term_tab [NumTerm]. Left: =0;

Term_tab [NumTerm]. Right: =0;

Term_tab [NumTerm]. Way: =Term_tab [NumTerm]. Way+'R';

end else begin

Term_tab [NumTerm]. Way: =Term_tab [NumTerm]. Way+'R';

Add_Term (Term_tab [Curr_term]. Right,str_lex); // Если правый указатель существует, то вызываем уже функцию для правого указателя.

end;

end;

procedure Add_Ident (str: string); //

процедура добавления константы

var i: integer;

begin

kod: =Length (str) +2;

hesh: =0;

for i: =1 to Length (str) do hesh: =hesh+ord (str [i]); // вычисление хэш

hesh: =round (hesh/kod); // метод деления

while (Id_tab [hesh]. lex<>'') and (hesh<maxnum) do // пока ячейка занята

begin

Id_tab [hesh]. ssylka: =hesh+1;

hesh: =hesh+1;

end;

Id_tab [hesh]. nomer: =Numid; // запись данных

Id_tab [hesh]. lex: =str;

end;

function Search_Ident (str: string): integer; // функция поиска терминала

var i: integer;

label 1;

begin

kod: =Length (str) +2;

hesh: =0;

for i: =1 to Length (str) do hesh: =hesh+ord (str [i]); // вычисление хэш

hesh: =round (hesh/kod);

1: if str=Id_tab [hesh]. lex then Search_Ident: =Id_tab [hesh]. nomer else // поиск идентификатора

begin

if Id_tab [hesh]. ssylka=0 then Search_Ident: =0 else

begin

hesh: =Id_tab [hesh]. ssylka;

goto 1;

end;

end;

end;

procedure Search_Const (Curr_term: integer; str_lex: string); // Процедура поиска лексем в дереве идентификаторов

begin

Constyes: =0; // флаг: найдена ли лексема

if (NumConst<>0) and (str_lex<>'') then

begin

if (CompareStr (Const_tab [Curr_term]. value,str_lex) >0) and (Const_tab [Curr_term]. Left<>0) then

Search_Const (Const_tab [Curr_term]. Left,str_lex); // рекурсивный "спуск по дереву"

if (CompareStr (Const_tab [Curr_term]. value,str_lex) <0) and (Const_tab [Curr_term]. Right<>0) then

Search_Const (Const_tab [Curr_term]. Right,str_lex);

if Const_tab [Curr_term]. value=str_lex then Constyes: =Const_tab [Curr_term]. nomer;

end;

end;

procedure Search_Term (Curr_term: integer; str_lex: string); // Процедура поиска лексем в дереве идентификаторов

begin

Termyes: =0; // флаг: найдена ли лексема

if (NumTerm<>0) and (str_lex<>'') then

begin

if (CompareStr (Term_tab [Curr_term]. lex,str_lex) >0) and (Term_tab [Curr_term]. Left<>0) then

Search_Term (Term_tab [Curr_term]. Left,str_lex); // рекурсивный "спуск по дереву"

if (CompareStr (Term_tab [Curr_term]. lex,str_lex) <0) and (Term_tab [Curr_term]. Right<>0) then

Search_Term (Term_tab [Curr_term]. Right,str_lex);

if Term_tab [Curr_term]. lex=str_lex then Termyes: =Term_tab [Curr_term]. nomer;

end;

end;

// функция распознавания 16-рич. констант

function FConst (str: string): integer;

var

sost: byte;

begin

sost: =0;

if str [1] ='$' then // распознаём символ '$'

begin

sost: =1;

delete (str,1,1);

end

else exit;

if (str [1] ='+') or (str [1] ='-') then // распознаём знак

begin

sost: =2;

delete (str,1,1)

end

else begin sost: =4; exit; end;

if str='' then exit;

while length (str) >0 do begin

if (str [1] in cifra) or (str [1] in bukva)

then sost: =2 // распознаём буквы или цифры

else begin sost: =4; exit;

end;

delete (str,1,1);

end;

sost: =3;

if sost=3 then FConst: =1 else FConst: =-1;

end;

function termin: integer; // распознаватель терминальных символов

begin

termin: =-1;

for k: =1 to 14 do if Words [k] =Lexem then termin: =3;

for k: =1 to 8 do if Razdel [k] =Lexem then termin: =1;

for k: =1 to 11 do if Operacii [k] =Lexem then termin: =2;

end;

function Rome (str: string): integer; // распознаватель римских констант

var sost: byte;

begin

sost: =0;

if (str [1] ='-') or (str [1] ='+')

then begin sost: =12; delete (str,1,1); end;

if str='' then exit;

if str [1] ='X'

then begin sost: =1; delete (str,1,1) end

else begin

if str [1] ='V' then begin sost: =2; delete (str,1,1) end

else begin

if str [1] ='I' then begin sost: =3; delete (str,1,1) end

else begin sost: =4; exit; end; end; end;

while Length (str) <>0 do begin

case sost of

1: if str [1] ='X'

then begin sost: =5; delete (str,1,1) end

else begin

if str [1] ='V' then begin sost: =2; delete (str,1,1) end

else begin

if str [1] ='I' then begin sost: =3; delete (str,1,1) end

else begin sost: =4; exit; end; end; end;

2: if str [1] ='I'

then begin sost: =7; delete (str,1,1) end

else begin sost: =4; exit; end;

3: if str [1] ='X'

then begin sost: =8; delete (str,1,1) end

else begin

if str [1] ='V' then begin sost: =9; delete (str,1,1) end

else begin

if str [1] ='I' then begin sost: =10; delete (str,1,1) end

else begin sost: =4; exit; end; end; end;

4: exit;

5: if str [1] ='X'

then begin sost: =6; delete (str,1,1) end

else begin

if str [1] ='V' then begin sost: =2; delete (str,1,1) end

else begin

if str [1] ='I' then begin sost: =3; delete (str,1,1) end

else begin sost: =4; exit; end; end; end;

6: if str [1] ='V'

then begin sost: =2; delete (str,1,1) end

else begin

if str [1] ='I' then begin sost: =3; delete (str,1,1) end

else begin sost: =4; exit; end; end;

7: if str [1] ='I'

then begin sost: =10; delete (str,1,1) end

else begin sost: =4; exit; end;

8: begin sost: =4; exit; end;

9: begin sost: =4; exit; end;

10: if str [1] ='I'

then begin sost: =11; delete (str,1,1) end

else begin sost: =4; exit; end;

11: begin sost: =4; exit; end;

end;

end;

if (sost=4) or (sost=12) then Rome: =-1 else Rome: =1;

end;

// функция распознавания идентификаторов

function Ident (str: string): integer;

var

sost: byte;

begin

sost: =0; // реализация конечного автомата

if str [1] in ['a'. 'z'] then

begin

sost: =1;

delete (str,1,1)

end

else exit;

while length (str) >0 do begin

if str [1] in ['a'. 'z','0'. '9','_']

then begin sost: =1; delete (str,1,1); end

else begin sost: =3; exit; end;

end;

sost: =2;

if sost=2 then ident: =1 else ident: =-1;

end;

procedure WriteCode (nomer: integer; lex: string; typ: char; num: integer); // запись в таблицу кодов лексем

begin

Code_Tab [NumLex]. nomer: =nomer;

Code_Tab [NumLex]. Lex: =lex;

Code_Tab [NumLex]. typ: =typ;

Code_Tab [NumLex]. Num: =num;

Code_Tab [NumLex]. numstr: =string_counter+1;

end;

procedure WriteLex (typelex: char); // запись лексем в таблицы

begin

case typelex of

'C': begin // если лексема-16-рич. константа

NumLex: =NumLex+1;

Search_Const (1,Lexem);

if Constyes=0 then // если лексема не найдена

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