source: mainline/uspace/app/pcc/arch/nova/order.c@ 087c27f6

/*      $Id: order.c,v 1.4 2008/09/27 07:35:23 ragge Exp $      */
/*
 * Copyright (c) 2006 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 "pass2.h"

#include <string.h>

int canaddr(NODE *);

/* is it legal to make an OREG or NAME entry which has an
 * offset of off, (from a register of r), if the
 * resulting thing had type t */
int
notoff(TWORD t, int r, CONSZ off, char *cp)
{
        if (r != 2 && r != 3)
                return 1; /* can only index ac2 and ac3 */
        if (t == CHAR || t == UCHAR) {
                if (off < -256 || off > 254)
                        return 1;
        } else if (off < -128 || off > 127)
                return 1;
        return(0);  /* YES */
}

/*
 * Turn a UMUL-referenced node into OREG.
 * Be careful about register classes, this is a place where classes change.
 */
void
offstar(NODE *p, int shape)
{
        NODE *r;

        if (x2debug)
                printf("offstar(%p)\n", p);

        if (isreg(p))
                return; /* Is already OREG */

        r = p->n_right;
        if( p->n_op == PLUS || p->n_op == MINUS ){
                if( r->n_op == ICON ){
                        if (isreg(p->n_left) == 0 ||
                            (p->n_left->n_op == REG &&
                            p->n_left->n_rval != 2 && p->n_left->n_rval != 3))
                                (void)geninsn(p->n_left, INBREG);
                        /* Converted in ormake() */
                        return;
                }
        }
        (void)geninsn(p, INBREG);
}

/*
 * Do the actual conversion of offstar-found OREGs into real OREGs.
 */
void
myormake(NODE *q)
{
        if (x2debug)
                printf("myormake(%p)\n", q);
}

/*
 * Shape matches for UMUL.  Cooperates with offstar().
 */
int
shumul(NODE *p, int order)
{

        if (x2debug)
                printf("shumul(%p)\n", p);

        /* Turns currently anything into OREG on x86 */
        if (shape & SOREG)
                return SROREG;
        return SRNOPE;
}

/*
 * Rewrite increment/decrement operation.
 */
int
setincr(NODE *p)
{
        if (x2debug)
                printf("setincr(%p)\n", p);

        return(0);
}

/*
 * Rewrite operations on binary operators (like +, -, etc...).
 * Called as a result of table lookup.
 */
int
setbin(NODE *p)
{

        if (x2debug)
                printf("setbin(%p)\n", p);
        return 0;

}

/* setup for assignment operator */
int
setasg(NODE *p, int cookie)
{
        if (x2debug)
                printf("setasg(%p)\n", p);
        return(0);
}

/* setup for unary operator */
int
setuni(NODE *p, int cookie)
{
        return 0;
}

/*
 * Special handling of some instruction register allocation.
 */
struct rspecial *
nspecial(struct optab *q)
{
        comperr("nspecial entry %d", q - table);
        return 0; /* XXX gcc */
}

/*
 * Set evaluation order of a binary node if it differs from default.
 */
int
setorder(NODE *p)
{
        return 0;
}
/*
 * Set registers "live" at function calls (like arguments in registers).
 * This is for liveness analysis of registers.
 */
int *
livecall(NODE *p)
{
        static int r[1] = { -1 }; /* Terminate with -1 */

        return &r[0];
}

/*
 * Signal whether the instruction is acceptable for this target.
 */
int
acceptable(struct optab *op)
{
        return 1;
}