ag: refactor fun

[uebersetzerbau-ss10.git] / ag / parser.y

diff --git a/ag/parser.y b/ag/parser.y
index 181bc5a0a9ffb6fb38474568b055587075fa3ade..dbd4e2412f340410fb84c702279515e8ba76f387 100644 (file)
--- a/ag/parser.y
+++ b/ag/parser.y
@@ -1,51 +1,167 @@
 %{
        #include <stdio.h>
        #include <stdlib.h>
+       #include <string.h>
+       #include "symtable.h"
 %}
 
-%start Program
-%token STRUCT END METHOD VAR IF THEN ELSE WHILE DO RETURN NOT OR THIS
-%token IDENT NUM
+%start Input
+%token STRUCT END METHOD VAR IF THEN ELSE WHILE DO RETURN NOT OR THIS IDENT NUM ASSIGN
+
+@macro xxputsin(xx,)
+       @i xx = @Statement.sin@;
+@end
+
+@macro statinout()
+       @i @Statement.sout@ = @Statement.sin@;
+       /* das
+        *> xxputsin(@Statement.sout@,)
+        * geht nicht, weil verschachtelte macros deaktiviert sind */
+@end
+
+@autoinh s
+@attributes { char *name; } IDENT
+@attributes { struct symbol *f; } FeldID Parms Structdef Program
+@attributes { struct symbol *s; } Methoddef Statseq Lexpr Expr Minusterm Multerm Orterm Term Exprs Feld
+@attributes { struct symbol *sin; struct symbol *sout; } Statement
+
+@traversal @postorder c
 
 %%
+Input:
+         Program
+         @{
+           @i @Program.f@ = tab_new();
+         @}
+       ;
 
 Program:
          Methoddef ';' Program
+         @{
+           @i @Methoddef.s@ = @Program.0.f@;
+           @i @Program.1.f@ = @Program.0.f@;
+         @}
+
        | Structdef ';' Program
+         @{
+           @i @Program.1.f@ = tab_merge(@Program.0.f@, @Structdef.f@, 1);
+         @}
        |
        ;
 
+Methoddef:
+         METHOD IDENT '(' Parms ')' Statseq END
+         @{
+           @i @Statseq.s@ = tab_merge(@Methoddef.s@, @Parms.f@, 0);
+         @}
+       ;
+
 Structdef:
-         STRUCT Idents END
+         STRUCT FeldID END
+         @{
+           @i @Structdef.f@ = @FeldID.f@;
+         @}
        ;
 
-Methoddef:
-         METHOD IDENT '(' Idents ')' Statseq END
+Parms:
+         /* lokale Vars werden in Statement in die tabelle eingefuegt */
+         IDENT Parms
+         @{
+           @i @Parms.0.f@ = tab_add_symbol(@Parms.1.f@, @IDENT.name@, S_VAR, 1);
+         @}
+
+       |
+         @{
+           @i @Parms.f@ = tab_new();
+         @}
        ;
 
-Idents:
-         IDENT Idents
+FeldID:
+         IDENT FeldID
+         @{
+           @i @FeldID.0.f@ = tab_add_symbol(@FeldID.1.f@, @IDENT.name@, S_FIELD, 1);
+         @}
+
        |
+         @{
+           @i @FeldID.f@ = tab_new();
+         @}
        ;
 
 Statseq:
          Statement ';' Statseq
+         @{
+               @i @Statement.sin@ = @Statseq.0.s@;
+               @i @Statseq.1.s@ = @Statement.sout@;
+         @}
+
        |
        ;
 
 Statement:
-         Lexpr ':=' Expr
-       | VAR IDENT ':=' Expr
+         Lexpr ASSIGN Expr
+         @{
+               statinout()
+               xxputsin(@Lexpr.s@,)
+               xxputsin(@Expr.s@,)
+         @}
+
+       | VAR IDENT ASSIGN Expr
+         @{
+               /* tab_clone ist hier noetig, vgl. folgendes statement
+                * > var x := x - 1; */
+               @i @Statement.sout@ = tab_add_symbol(tab_clone(@Statement.sin@), @IDENT.name@, S_VAR, 1);
+               xxputsin(@Expr.s@,)
+         @}
+
        | Expr
+         @{
+               statinout()
+               xxputsin(@Expr.s@,)
+         @}
+
        | IF Expr THEN Statseq END
+         @{
+               statinout()
+               xxputsin(@Expr.s@,)
+               xxputsin(@Statseq.s@,)
+         @}
+
        | IF Expr THEN Statseq ELSE Statseq END
+         @{
+               statinout()
+               xxputsin(@Expr.s@,)
+               xxputsin(@Statseq.0.s@,)
+               xxputsin(@Statseq.1.s@,)
+         @}
+
        | WHILE Expr DO Statseq END
+         @{
+               statinout()
+               xxputsin(@Expr.s@,)
+               xxputsin(@Statseq.s@,)
+         @}
+
        | RETURN Expr
+         @{
+               statinout()
+               xxputsin(@Expr.s@,)
+         @}
        ;
 
 Lexpr:
          IDENT
-       | Term '.' IDENT
+         @{
+               @c check(@Lexpr.s@, @IDENT.name@, S_VAR);
+         @}
+
+       | Feld
+       ;
+
+Feld: Term '.' IDENT
+         @{
+               @c check(@Feld.s@, @IDENT.name@, S_FIELD);
+         @}
        ;
 
 Expr:
@@ -73,26 +189,26 @@ Orterm:
        | OR Term
        ;
 
-
 Term:
          '(' Expr ')'
        | NUM
        | '-' NUM
        | THIS
        | IDENT
-       | Term '.' IDENT
+         @{
+               @c check(@Term.s@, @IDENT.name@, S_VAR);
+         @}
+
+       | Feld
        | IDENT '(' Exprs ')'
        | Term '.' IDENT '(' Exprs ')'
        ;
 
-/* beachte dass hier auch "nichts" vorkommen kann
- * sonst waer ein aufruf der art 'f()' nicht
- * moeglich (leere parameterliste) */
 Exprs:
+         Expr ',' Exprs
        | Expr
-       | Exprs ',' Expr
+       |
        ;
-
 %%
 
 extern int yylex();
@@ -100,7 +216,7 @@ extern int yylineno;
 
 int yyerror(char *error_text)
 {
-       fprintf(stderr,"Line %i: %s\n", yylineno, error_text);
+       fprintf(stderr,"Zeile %i: %s\n", yylineno, error_text);
        exit(2);
 }