/*	$OpenBSD: code.c,v 1.3 2007/12/19 20:19:54 otto Exp $	*/

/*
 * Copyright (c) 2007 Michael Shalayeff
 * Copyright (c) 2003 Anders Magnusson (ragge@ludd.luth.se).
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


# include "pass1.h"

NODE *funarg(NODE *, int *);

/*
 * cause the alignment to become a multiple of n
 * never called for text segment.
 */
void
defalign(int n)
{
	n /= SZCHAR;
	if (n == 1)
		return;
	printf("\t.align %d\n", n);
}

/*
 * define the current location as the name p->sname
 * never called for text segment.
 */
void
defnam(struct symtab *p)
{
	char *c = p->sname;

#ifdef GCC_COMPAT
	c = gcc_findname(p);
#endif
	if (p->sclass == EXTDEF)
		printf("\t.export %s, data\n", c);
	printf("\t.label %s\n", c);
}


/*
 * code for the end of a function
 * deals with struct return here
 */
void
efcode()
{
	NODE *p, *q;
	int sz;

	if (cftnsp->stype != STRTY+FTN && cftnsp->stype != UNIONTY+FTN)
		return;
	/* address of return struct is in eax */
	/* create a call to memcpy() */
	/* will get the result in %ret0 */
	p = block(REG, NIL, NIL, CHAR+PTR, 0, MKSUE(CHAR+PTR));
	p->n_rval = RET0;
	q = block(OREG, NIL, NIL, CHAR+PTR, 0, MKSUE(CHAR+PTR));
	q->n_rval = FP;
	q->n_lval = 8; /* return buffer offset */
	p = block(CM, q, p, INT, 0, MKSUE(INT));
	sz = (tsize(STRTY, cftnsp->sdf, cftnsp->ssue)+SZCHAR-1)/SZCHAR;
	p = block(CM, p, bcon(sz), INT, 0, MKSUE(INT));
	p->n_right->n_name = "";
	p = block(CALL, bcon(0), p, CHAR+PTR, 0, MKSUE(CHAR+PTR));
	p->n_left->n_name = "memcpy";
	p = clocal(p);
	send_passt(IP_NODE, p);
}

/*
 * code for the beginning of a function; 'a' is an array of
 * indices in symtab for the arguments; n is the number
 */
void
bfcode(struct symtab **a, int n)
{
	int i;

	if (cftnsp->stype != STRTY+FTN && cftnsp->stype != UNIONTY+FTN)
		return;
	/* Function returns struct, adjust arg offset */
	for (i = 0; i < n; i++)
		a[i]->soffset += SZPOINT(INT);
}


/*
 * by now, the automatics and register variables are allocated
 */
void
bccode()
{
	SETOFF(autooff, SZINT);
}

/* called just before final exit */
/* flag is 1 if errors, 0 if none */
void
ejobcode(int errors)
{
	if (errors)
		return;

	printf("\t.end\n");
}

void
bjobcode(void)
{
	printf("\t.import $global$, data\n");
}

/*
 * Print character t at position i in one string, until t == -1.
 * Locctr & label is already defined.
 */
void
bycode(int t, int i)
{
	static	int	lastoctal = 0;

	/* put byte i+1 in a string */

	if (t < 0) {
		if (i != 0)
			puts("\"");
	} else {
		if (i == 0)
			printf("\t.ascii\t\"");
		if (t == '\\' || t == '"') {
			lastoctal = 0;
			putchar('\\');
			putchar(t);
		} else if (t < 040 || t >= 0177) {
			lastoctal++;
			printf("\\%o",t);
		} else if (lastoctal && '0' <= t && t <= '9') {
			lastoctal = 0;
			printf("\"\n\t.ascii\t\"%c", t);
		} else {	
			lastoctal = 0;
			putchar(t);
		}
	}
}

/*
 * return the alignment of field of type t
 */
int
fldal(unsigned int t)
{
	uerror("illegal field type");
	return(ALINT);
}

/* fix up type of field p */
void
fldty(struct symtab *p)
{
}

/*
 * XXX - fix genswitch.
 */
int
mygenswitch(int num, TWORD type, struct swents **p, int n)
{
	return 0;
}

NODE *
funarg(NODE *p, int *n)
{
	NODE *r;
	int sz;

	if (p->n_op == CM) {
		p->n_left = funarg(p->n_left, n);
		p->n_right = funarg(p->n_right, n);
		return p;
	}

	sz = szty(p->n_type);
	if (*n % sz)
		(*n)++;	/* XXX */

	if (*n >= 4) {
		*n += sz;
		r = block(OREG, NIL, NIL, p->n_type|PTR, 0,
		    MKSUE(p->n_type|PTR));
		r->n_rval = SP;
		r->n_lval = -(32 + *n * 4);
	} else {
		r = block(REG, NIL, NIL, p->n_type, 0, 0);
		r->n_lval = 0;
		switch (p->n_type) {
		case FLOAT:
			r->n_rval = FR7L - 2 * (*n)++;
			break;
		case DOUBLE:
		case LDOUBLE:
			*n = (*n + 1) & ~1;
			r->n_rval = FR6 - *n;
			*n += 2;
			break;
		case LONGLONG:
		case ULONGLONG:
			*n = (*n + 1) & ~1;
			r->n_rval = AD1 - *n / 2;
			*n += 2;
			break;
		default:
			r->n_rval = ARG0 - (*n)++;
		}
	}
	p = block(ASSIGN, r, p, p->n_type, 0, 0);
	clocal(p);

	return p;
}

/*
 * Called with a function call with arguments as argument.
 * This is done early in buildtree() and only done once.
 */
NODE *
funcode(NODE *p)
{
	int n = 0;

	p->n_right = funarg(p->n_right, &n);
	return p;
}