compilers-lab1/parser.y

%{
	#include <stdio.h>
	#include "node.h"
	extern int yylex(void);
	extern int yylineno;
	int errors = 0;
	struct node;
	void yyerror(char const *);
	pNode root;
%}

%define api.value.type {struct node*}

%token INTEGER FLOAT
%token SEMI COMMA ASSIGNOP PLUS MINUS TIMES DIV AND OR DOT NOT LP RP LB RB LC RC STRUCT RETURN IF ELSE WHILE
%token TYPE_INT TYPE_FLOAT ID
%token LINE_COMMENT BLOCK_COMMENT

%%

// High-level Definitions
Program:
     	ExtDefList {
		pNode children[1] = { $1 };
		$$ = newNode(Program, $1->line, 1, children, nullValue());
		root = $$;
	}
	;
ExtDefList:
	ExtDef ExtDefList {
		pNode children[2] = { $1, $2 };
		$$ = newNode(ExtDefList, $1->line, 2, children, nullValue());
	}
    	| {
		$$ = newNode(ExtDefList, -1, 0, NULL, nullValue());
	}
    	;
ExtDef:
      	Specifier ExtDecList SEMI {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(ExtDef, $1->line, 3, children, nullValue());
	}
    	| Specifier SEMI {
		pNode children[2] = { $1, $2 };
		$$ = newNode(ExtDef, $1->line, 2, children, nullValue());
	}
    	| Specifier FunDec CompSt {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(ExtDef, $1->line, 3, children, nullValue());
	}
    	;
ExtDecList:
	VarDec {
		pNode children[1] = { $1 };
		$$ = newNode(ExtDecList, $1->line, 1, children, nullValue());
	}
    	| VarDec COMMA ExtDecList {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(ExtDecList, $1->line, 3, children, nullValue());
	}
    	;

// Specifiers
Specifier:
	TYPE_INT {
		pNode children[1] = { $1 };
		$$ = newNode(Specifier, $1->line, 1, children, nullValue());
	}
	| TYPE_FLOAT {
		pNode children[1] = { $1 };
		$$ = newNode(Specifier, $1->line, 1, children, nullValue());
	}
    	| StructSpecifier {
		pNode children[1] = { $1 };
		$$ = newNode(Specifier, $1->line, 1, children, nullValue());
	}
    	;
StructSpecifier:
	STRUCT OptTag LC DefList RC {
		pNode children[5] = { $1, $2, $3, $4, $5 };
		$$ = newNode(StructSpecifier, $1->line, 5, children, nullValue());
	}
    	| STRUCT Tag {
		pNode children[2] = { $1, $2 };
		$$ = newNode(StructSpecifier, $1->line, 2, children, nullValue());
	}
    	;
OptTag:
   	ID {
		pNode children[1] = { $1 };
		$$ = newNode(OptTag, $1->line, 1, children, nullValue());
	}
    	| {
		$$ = newNode(OptTag, -1, 0, NULL, nullValue());
	}
    	;   
Tag:
   	ID {
		pNode children[1] = { $1 };
		$$ = newNode(Tag, $1->line, 1, children, nullValue());
	}
    	;

// Declarators
VarDec:
   	ID {
		pNode children[1] = { $1 };
		$$ = newNode(VarDec, $1->line, 1, children, nullValue());
	}
    	| VarDec LB INTEGER RB {
		pNode children[4] = { $1, $2, $3, $4 };
		$$ = newNode(VarDec, $1->line, 4, children, nullValue());
	}
    	;
FunDec:
    	ID LP VarList RP {
		pNode children[4] = { $1, $2, $3, $4 };
		$$ = newNode(FunDec, $1->line, 4, children, nullValue());
	}
    	| ID LP RP {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(FunDec, $1->line, 3, children, nullValue());
	}
    	;
VarList:
       	ParamDec COMMA VarList {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(VarList, $1->line, 3, children, nullValue());
	}
    	| ParamDec {
		pNode children[1] = { $1 };
		$$ = newNode(VarList, $1->line, 1, children, nullValue());
	}
    	;
ParamDec:
	Specifier VarDec {
		pNode children[1] = { $1 };
		$$ = newNode(ParamDec, $1->line, 1, children, nullValue());
	}
    	;

// Statements
CompSt:
    	LC DefList StmtList RC {
		pNode children[4] = { $1, $2, $3, $4 };
		$$ = newNode(CompSt, $1->line, 4, children, nullValue());
	}
    	;
StmtList:
	Stmt StmtList {
		pNode children[2] = { $1, $2 };
		$$ = newNode(StmtList, $1->line, 2, children, nullValue());
	}
    	| {
		$$ = newNode(StmtList, -1, 0, NULL, nullValue());
	}
    	;
Stmt:
    	Exp SEMI {
		pNode children[2] = { $1, $2 };
		$$ = newNode(Stmt, $1->line, 2, children, nullValue());
	}
    	| CompSt {
		pNode children[1] = { $1 };
		$$ = newNode(Stmt, $1->line, 1, children, nullValue());
	}
    	| RETURN Exp SEMI {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Stmt, $1->line, 3, children, nullValue());
	}
    	| IF LP Exp RP Stmt {
		pNode children[5] = { $1, $2, $3, $4, $5 };
		$$ = newNode(Stmt, $1->line, 5, children, nullValue());
	}
    	| IF LP Exp RP Stmt ELSE Stmt {
		pNode children[7] = { $1, $2, $3, $4, $5, $6, $7 };
		$$ = newNode(Stmt, $1->line, 7, children, nullValue());
	}
    	| WHILE LP Exp RP Stmt {
		pNode children[5] = { $1, $2, $3, $4, $5 };
		$$ = newNode(Stmt, $1->line, 5, children, nullValue());
	}
	| error SEMI
    	;

// Local Definitions
DefList:
       	Def DefList {
		pNode children[2] = { $1, $2 };
		$$ = newNode(DefList, $1->line, 2, children, nullValue());
	}
    	| {
		$$ = newNode(DefList, -1, 0, NULL, nullValue());
	}
    	;
Def:
   	Specifier DecList SEMI {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Def, $1->line, 3, children, nullValue());
	}
    	;
DecList:
       	Dec {
		pNode children[1] = { $1 };
		$$ = newNode(DecList, $1->line, 1, children, nullValue());
	}
    	| Dec COMMA DecList {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(DecList, $1->line, 3, children, nullValue());
	}
    	;
Dec:
   	VarDec {
		pNode children[1] = { $1 };
		$$ = newNode(Dec, $1->line, 1, children, nullValue());
	}
    	| VarDec ASSIGNOP Exp {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Dec, $1->line, 3, children, nullValue());
	}
    	;

// Expressions
Exp:
   	Exp ASSIGNOP Exp {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| Exp AND Exp {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| Exp OR Exp {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| Exp PLUS Exp {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| Exp MINUS Exp {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| Exp TIMES Exp {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| Exp DIV Exp {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| LP Exp RP {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| MINUS Exp {
		pNode children[2] = { $1, $2 };
		$$ = newNode(Exp, $1->line, 2, children, nullValue());
	}
    	| NOT Exp {
		pNode children[2] = { $1, $2 };
		$$ = newNode(Exp, $1->line, 2, children, nullValue());
	}
    	| ID LP Args RP {
		pNode children[4] = { $1, $2, $3, $4 };
		$$ = newNode(Exp, $1->line, 4, children, nullValue());
	}
    	| ID LP RP {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| Exp LB Exp RB {
		pNode children[4] = { $1, $2, $3, $4 };
		$$ = newNode(Exp, $1->line, 4, children, nullValue());
	}
    	| Exp DOT ID {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Exp, $1->line, 3, children, nullValue());
	}
    	| ID {
		pNode children[1] = { $1 };
		$$ = newNode(Exp, $1->line, 1, children, nullValue());
	}
    	| INTEGER {
		pNode children[1] = { $1 };
		$$ = newNode(Exp, $1->line, 1, children, nullValue());
	}
    	| FLOAT {
		pNode children[1] = { $1 };
		$$ = newNode(Exp, $1->line, 1, children, nullValue());
	}
    	;

Args:
   	Exp COMMA Args {
		pNode children[3] = { $1, $2, $3 };
		$$ = newNode(Args, $1->line, 3, children, nullValue());
	}
    	| Exp {
		pNode children[1] = { $1 };
		$$ = newNode(Exp, $1->line, 1, children, nullValue());
	}
    	;

%%

void yyerror(char const *s) {
	errors += 1;
	fprintf(stderr, "Error type B at Line %d: \"%s\".\n", yylineno, s);
}