static asm86_t *ack_get_statement(void)
/* Get a pseudo op or machine instruction with arguments. */
{
	token_t *t= get_token(0);
	asm86_t *a;
	mnemonic_t *m;
	int n;
	int prefix_seen;
	int oaz_prefix;
	int deref;

	assert(t->type == T_WORD);

	if (strcmp(t->name, ".sect") == 0) {
		/* .sect .text etc.  Accept only four segment names. */
		skip_token(1);
		t= get_token(0);
		if (t->type != T_WORD || (
			strcmp(t->name, ".text") != 0
			&& strcmp(t->name, ".rom") != 0
			&& strcmp(t->name, ".data") != 0
			&& strcmp(t->name, ".bss") != 0
			&& strcmp(t->name, ".end") != 0
		)) {
			parse_err(1, t, "weird section name to .sect\n");
			return nil;
		}
	}
	a= new_asm86();

	/* Process instruction prefixes. */
	oaz_prefix= 0;
	for (prefix_seen= 0;; prefix_seen= 1) {
		if (strcmp(t->name, "o16") == 0) {
			if (use16()) {
				parse_err(1, t, "o16 in an 8086 section\n");
			}
			oaz_prefix|= OPZ;
		} else
		if (strcmp(t->name, "o32") == 0) {
			if (use32()) {
				parse_err(1, t, "o32 in an 80386 section\n");
			}
			oaz_prefix|= OPZ;
		} else
		if (strcmp(t->name, "a16") == 0) {
			if (use16()) {
				parse_err(1, t, "a16 in an 8086 section\n");
			}
			oaz_prefix|= ADZ;
		} else
		if (strcmp(t->name, "a32") == 0) {
			if (use32()) {
				parse_err(1, t, "a32 in an 80386 section\n");
			}
			oaz_prefix|= ADZ;
		} else
		if (strcmp(t->name, "rep") == 0
			|| strcmp(t->name, "repe") == 0
			|| strcmp(t->name, "repne") == 0
			|| strcmp(t->name, "repz") == 0
			|| strcmp(t->name, "repnz") == 0
		) {
			if (a->rep != ONCE) {
				parse_err(1, t,
					"can't have more than one rep\n");
			}
			switch (t->name[3]) {
			case 0:		a->rep= REP;	break;
			case 'e':
			case 'z':	a->rep= REPE;	break;
			case 'n':	a->rep= REPNE;	break;
			}
		} else
		if (strchr("cdefgs", t->name[0]) != nil
					&& strcmp(t->name+1, "seg") == 0) {
			if (a->seg != DEFSEG) {
				parse_err(1, t,
				"can't have more than one segment prefix\n");
			}
			switch (t->name[0]) {
			case 'c':	a->seg= CSEG;	break;
			case 'd':	a->seg= DSEG;	break;
			case 'e':	a->seg= ESEG;	break;
			case 'f':	a->seg= FSEG;	break;
			case 'g':	a->seg= GSEG;	break;
			case 's':	a->seg= SSEG;	break;
			}
		} else
		if (!prefix_seen) {
			/* No prefix here, get out! */
			break;
		} else {
			/* No more prefixes, next must be an instruction. */
			if (t->type != T_WORD
				|| (m= search_mnem(t->name)) == nil
				|| m->optype == PSEUDO
			) {
				parse_err(1, t,
		"machine instruction expected after instruction prefix\n");
				del_asm86(a);
				return nil;
			}
			if (oaz_prefix != 0 && m->optype != JUMP
						&& m->optype != WORD) {
				parse_err(1, t,
			"'%s' can't have an operand size prefix\n", m->name);
			}
			break;
		}

		/* Skip the prefix and extra newlines. */
		do {
			skip_token(1);
		} while ((t= get_token(0))->symbol == ';');
	}

	/* All the readahead being done upsets the line counter. */
	a->line= t->line;

	/* Read a machine instruction or pseudo op. */
	if ((m= search_mnem(t->name)) == nil) {
		parse_err(1, t, "unknown instruction '%s'\n", t->name);
		del_asm86(a);
		return nil;
	}
	a->opcode= m->opcode;
	a->optype= m->optype;
	a->oaz= oaz_prefix;

	switch (a->opcode) {
	case IN:
	case OUT:
	case INT:
		deref= 0;
		break;
	default:
		deref= (a->optype >= BYTE);
	}
	n= 1;
	if (get_token(1)->symbol != ';'
			&& (a->args= ack_get_oplist(&n, deref)) == nil) {
		del_asm86(a);
		return nil;
	}
	if (get_token(n)->symbol != ';') {
		parse_err(1, t, "garbage at end of instruction\n");
		del_asm86(a);
		return nil;
	}
	switch (a->opcode) {
	case DOT_ALIGN:
		/* Restrict .align to have a single numeric argument, some
		 * assemblers think of the argument as a power of two, so
		 * we need to be able to change the value.
		 */
		if (a->args == nil || a->args->operator != 'W'
					|| !isanumber(a->args->name)) {
			parse_err(1, t,
			  ".align is restricted to one numeric argument\n");
			del_asm86(a);
			return nil;
		}
		break;
	case JMPF:
	case CALLF:
		/* NCC jmpf off,seg  ->  ACK jmpf seg:off */
		if (dialect == NCC && a->args != nil
						&& a->args->operator == ',') {
			expression_t *t;

			t= a->args->left;
			a->args->left= a->args->right;
			a->args->right= t;
			break;
		}
		/*FALL THROUGH*/
	case JMP:
	case CALL:
		/* NCC jmp @(reg)  ->  ACK jmp (reg) */
		if (dialect == NCC && a->args != nil && (
			(a->args->operator == '('
				&& a->args->middle != nil
				&& a->args->middle->operator == 'O')
			|| (a->args->operator == 'O'
				&& a->args->left == nil
				&& a->args->middle != nil
				&& a->args->right == nil)
		)) {
			expression_t *t;

			t= a->args;
			a->args= a->args->middle;
			t->middle= nil;
			del_expr(t);
			if (a->args->operator == 'B') a->args->operator= 'W';
		}
		break;
	default:;
	}
	skip_token(n+1);
	return a;
}
Beispiel #2
0
static asm86_t *gnu_get_statement(void)
/* Get a pseudo op or machine instruction with arguments. */
{
	token_t *t= get_token(0);
	token_t *tn;
	asm86_t *a;
	mnemonic_t *m;
	int n;
	int prefix_seen;
	int deref;

	assert(t->type == T_WORD);

	a= new_asm86();

	/* Process instruction prefixes. */
	for (prefix_seen= 0;; prefix_seen= 1) {
		if (strcmp(t->name, "rep") == 0
			|| strcmp(t->name, "repe") == 0
			|| strcmp(t->name, "repne") == 0
			|| strcmp(t->name, "repz") == 0
			|| strcmp(t->name, "repnz") == 0
		) {
			if (a->rep != ONCE) {
				parse_err(1, t,
					"can't have more than one rep\n");
			}
			switch (t->name[3]) {
			case 0:		a->rep= REP;	break;
			case 'e':
			case 'z':	a->rep= REPE;	break;
			case 'n':	a->rep= REPNE;	break;
			}
		} else
		if (!prefix_seen) {
			/* No prefix here, get out! */
			break;
		} else {
			/* No more prefixes, next must be an instruction. */
			if (t->type != T_WORD
				|| (m= search_mnem(t->name)) == nil
				|| m->optype == PSEUDO
			) {
				parse_err(1, t,
		"machine instruction expected after instruction prefix\n");
				del_asm86(a);
				return nil;
			}
			break;
		}

		/* Skip the prefix and extra newlines. */
		do {
			skip_token(1);
		} while ((t= get_token(0))->symbol == ';');
	}

	/* All the readahead being done upsets the line counter. */
	a->line= t->line;

	/* Read a machine instruction or pseudo op. */
	if ((m= search_mnem(t->name)) == nil) {
		/* we assume that unknown stuff is part of unresolved macro */
		a->opcode = UNKNOWN;
		if (zap_unknown(a)) {
			parse_err(1, t, "unknown instruction '%s'\n", t->name);
			del_asm86(a);
			return nil;
		}
		return a;
	}
	a->opcode= m->opcode;
	a->optype= m->optype;
	a->oaz= 0;
	if (a->optype == OWORD) {
		a->oaz|= OPZ;
		a->optype= WORD;
	}
	else if (a->optype == JUMP16) {
		a->oaz|= OPZ;
		a->optype= JUMP;
	}

	switch (a->opcode) {
	case IN:
	case OUT:
	case INT:
		deref= 0;
		break;
	default:
		deref= (a->optype >= BYTE);
	}
	n= 1;
	if (get_token(1)->type != T_COMMENT && get_token(1)->symbol != ';'
			&& (a->args= gnu_get_oplist(a, &n, deref)) == nil) {
		del_asm86(a);
		return nil;
	}
	tn = get_token(n);
	if (tn->type == T_COMMENT) {
		a->raw_string = malloc(tn->len + 1);
		if (!a->raw_string)
			return NULL;

		strcpy(a->raw_string, tn->name);
	} else
	if (get_token(n)->symbol != ';') {
		parse_err(1, t, "garbage at end of instruction\n");
		del_asm86(a);
		return nil;
	}
	if (!is_pseudo(a->opcode)) {
		/* GNU operand order is the other way around. */
		expression_t *e, *t;

		e= a->args;
		while (e != nil && e->operator == ',') {
			t= e->right; e->right= e->left; e->left= t;
			e= e->left;
		}
	}
	switch (a->opcode) {
	case DOT_ALIGN:
		/* Delete two argument .align, because ACK can't do it.
		 */
		if (a->args == nil || a->args->operator != 'W') {	
			del_asm86(a);
			return nil;
		}
		if (a->args != nil && a->args->operator == 'W'
			&& isanumber(a->args->name)
		) {	
			unsigned n;
			char num[sizeof(int) * CHAR_BIT / 3 + 1];

			n= strtoul(a->args->name, nil, 0);
			sprintf(num, "%u", n);
			deallocate(a->args->name);
			a->args->name= copystr(num);
		}
		break;
	case DOT_DEFINE:
	case DOT_EXTERN:
		syms_add_global_csl(a->args);
		break;
	case DOT_COMM:
		syms_add_global(a->args->left->name);
		break;
	case DOT_LCOMM:
		syms_add(a->args->left->name);
		break;
	case JMPF:
	case CALLF:
		/*FALL THROUGH*/
	case JMP:
	case CALL:
		break;
	default:;
	}
	skip_token(n+1);
	return a;
}