#ifndef	INPUT_INCLUDED
#define	INPUT_INCLUDED


//Macros for constant values
//which are used in a number of data structures below
#define SYM			0
#define VAL			1
#define OP 			2

#define STRING  		0
#define EXP			1

#define LBL			0
#define MNM			1
#define DIR			2


typedef enum {
	ADD, ADDCC, ADDX, ADDXCC, SUB, SUBCC, SUBX, SUBXCC, MULSCC, 
	AND, ANDCC, ANDN, ANDNCC, 
	OR, ORCC, ORN, ORNCC, 
	XOR, XORCC, XNOR, XNORCC, 
	SLL, SRL, SRA, 
	LDUB, LDSB, LDUH, LDSH, LD, LDD, 
	STB, STH, ST, STD, SWAP, 
	BA, BN, BE, BNE, BL, BLE, BGE, BG, BLU, BLEU, BGEU, BGU, 
	BPOS, BNEG, BCS, BCC, BVS, BVC, 
	TA, 
	CALL, JMPL, RETT, SETHI, SAVE, RESTORE, 
	CMP, TST, RET, NOT, NEG, INC, INCCC, DEC, DECCC, MOV, NOP
} Mnemonic_Type;

typedef enum {R, G, O, L, I, SP, FP} Register_Type;

struct register_info {
	Register_Type reg_type;
	int reg_number;
};

typedef enum {
	BIT_OR, BIT_XOR, BIT_AND, 
	LSHIFT, RSHIFT, PLUS, MINUS, MUL, DIV, MODULO, 
	UMINUS, COMPLEMENT, HI, LO
} Operation_Type;

struct operation {
	Operation_Type op_type;
	struct expression *left; //left is NULL for unary operation
	struct expression *right;
};

struct expression {
        int exp_type; //SYM, VAL, OP 
        union {
		char *sym;
		int val;
		struct operation *op;
	} u;
};

struct mnemonic {
	Mnemonic_Type mnm_type;
	int format; 
	union {
		struct register_info *reg;
	 	struct expression *exp;
	} u[3];
};

typedef enum {
	ASCII, ASCIZ, SECTION, SKIP, ALIGN, 
	BYTE, HALF, WORD, GLOBAL
} Directive_Type;

struct argument {
	int arg_type; //STRING or EXP
	union {
		char *string;
		struct expression *exp;
	} u;
	struct argument *next;
};

struct directive {
	Directive_Type dir_type;
	struct argument *arg_list;
};

struct instruction {
	int instr_type; //LBL, MNM, or DIR 
	union {
		char *lbl; 
		struct mnemonic *mnm;
	 	struct directive *dir;
	} u;
	struct instruction *next;
};


extern struct instruction *first;


extern int input (void);


#endif