/* $Id: order.c,v 1.5 2007/11/26 00:10:03 gmcgarry Exp $ */
/*
* 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 <assert.h>
# 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 (cp && cp[0]) return 1;
return !(off < 32768 && off > -32769); /* 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)
(void)geninsn(p->n_left, INAREG);
/* Converted in ormake() */
return;
}
/* usually for arraying indexing: */
if (r->n_op == LS && r->n_right->n_op == ICON &&
r->n_right->n_lval == 2 && p->n_op == PLUS) {
if (isreg(p->n_left) == 0)
(void)geninsn(p->n_left, INAREG);
if (isreg(r->n_left) == 0)
(void)geninsn(r->n_left, INAREG);
return;
}
}
(void)geninsn(p, INAREG);
}
/*
* Do the actual conversion of offstar-found OREGs into real OREGs.
*/
void
myormake(NODE *q)
{
#if 1
NODE *p, *r;
#endif
if (x2debug)
printf("myormake(%p)\n", q);
#if 1 /* XXX remove this and add UMUL(SAREG) to table.c !!! */
p = q->n_left;
if (q->n_op != OREG && p->n_op == REG) {
q->n_op = OREG;
q->n_lval = 0;
q->n_rval = p->n_rval;
tfree(p);
return;
}
#endif
#if 1
/* usually for array indexing */
p = q->n_left;
if (p->n_op == PLUS && (r = p->n_right)->n_op == LS &&
r->n_right->n_op == ICON && r->n_right->n_lval == 2 &&
p->n_left->n_op == REG && r->n_left->n_op == REG) {
if (isreg(p->n_left) == 0)
(void)geninsn(p->n_left, INAREG);
q->n_op = OREG;
q->n_lval = 0;
q->n_rval = p->n_left->n_rval;
tfree(p);
}
#endif
#if 0
if ((p->n_op == PLUS || p->n_op == MINUS) && p->n_right->n_op == ICON) {
if (isreg(p->n_left) == 0)
(void)geninsn(p->n_left, INAREG);
if (isreg(p->n_right) == 0)
(void)geninsn(p->n_right, INAREG);
(void)geninsn(p, INAREG);
} else if (p->n_op == REG) {
q->n_op = OREG;
q->n_lval = p->n_lval;
q->n_rval = p->n_rval;
tfree(p);
}
#endif
(void)geninsn(p, INAREG);
}
/*
* Shape matches for UMUL. Cooperates with offstar().
*/
int
shumul(NODE *p)
{
if (x2debug)
printf("shumul(%p)\n", p);
/* Turns currently anything into OREG on x86 */
return SOREG;
}
/*
* 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)
{
if (x2debug)
printf("nspecial: op=%d, visit=0x%x: %s", q->op, q->visit, q->cstring);
switch (q->op) {
case STASG:
{
static struct rspecial s[] = {
{ NEVER, R3 },
{ NRIGHT, R4 },
{ NEVER, R5 },
{ 0 } };
return s;
}
break;
case OPLTYPE:
{
if (q->visit & SAREG) {
static struct rspecial s[] = {
{ NEVER, R0 },
// { NRES, R3 }, // hack - i don't know why
{ 0 } };
return s;
}
}
break;
case ASSIGN:
if (q->lshape & SNAME) {
static struct rspecial s[] = {
{ NEVER, R0 },
{ 0 } };
return s;
} else if (q->rshape & SNAME) {
static struct rspecial s[] = {
{ NOLEFT, R0 },
{ 0 } };
return s;
} else if (q->lshape & SOREG) {
static struct rspecial s[] = {
{ NOLEFT, R0 },
{ 0 } };
return s;
} else if (q->rshape & SOREG) {
static struct rspecial s[] = {
{ NORIGHT, R0 },
{ 0 } };
return s;
}
/* fallthough */
case SCONV:
case UMUL:
case MINUS:
case AND:
case OR:
case ER:
case PLUS:
{
static struct rspecial s[] = {
{ NOLEFT, R0 },
{ 0 } };
return s;
}
default:
break;
}
comperr("nspecial entry %d: %s", q - table, q->cstring);
return 0; /* XXX gcc */
}
/*
* Set evaluation order of a binary node if it differs from default.
*/
int
setorder(NODE *p)
{
return 0; /* nothing differs on x86 */
}
/*
* Set registers "live" at function calls (like arguments in registers).
* This is for liveness analysis of registers.
*/
int *
livecall(NODE *p)
{
static int r[] = { R3, R4, R5, R6, R7, R8, R9, R10, -1 };
return &r[0];
}
/*
* Signal whether the instruction is acceptable for this target.
*/
int
acceptable(struct optab *op)
{
return 1;
}
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