/* Copyright (c) 1979 Regents of the University of California */

static char sccsid[] = "@(#)tmps.c 1.7 02/01/83";

#include "whoami.h"
#include "0.h"
#include "objfmt.h"
#ifdef PC
#   include "pc.h"
#endif PC

/*
 * This routine defines the register allocation strategy
 * All temporaries are allocated here, and this routines decides
 * where they are to be put.
 */
#ifdef PC
#ifdef vax
#    define MAXREGS 6
#    define MINREGSIZE 4
#    define MAXREGSIZE 4
#    define FIRSTREG 6
#endif vax
#ifdef pdp11
#    define MAXREGS 3
#    define MINREGSIZE 2
#    define MAXREGSIZE 2
#    define FIRSTREG 2
#endif pdp11
#if (!(vax || pdp11))
#    define MAXREGS 0
#    define MINREGSIZE 0
#    define MAXREGSIZE 0
#    define FIRSTREG 0
#endif
#endif PC

/*
 * allocate runtime temporary variables
 */
struct nl *
tmpalloc(size, type, mode)
	long size;
	struct nl *type;
	int mode;
{
	register struct om *op = &sizes[ cbn ];
	register int offset;
	register struct nl	*nlp;

#	ifdef PC
	    if (mode == REGOK && size >= MINREGSIZE && size <= MAXREGSIZE &&
		op->curtmps.reg_off < MAXREGS) {
		    offset = op->curtmps.reg_off++;
		    if ( offset > op->reg_max ) {
			    op->reg_max = offset;
		    }
		    nlp = defnl( 0 , VAR , type , offset + FIRSTREG );
		    nlp -> extra_flags = NLOCAL | NREGVAR;
		    return nlp;
	    }
#	endif PC
        offset = op->curtmps.om_off =
	    roundup((int)(op->curtmps.om_off - size), (long)align(type));
	if ( offset < op->om_max ) {
	        op->om_max = offset;
	}
	nlp = defnl( 0 , VAR , type , offset );
#	ifdef PC
	    nlp -> extra_flags = NLOCAL;
	    putlbracket( ftnno , -offset );
#	endif PC
	return nlp;
}

/*
 * deallocate runtime temporary variables
 */
tmpfree(restore)
	register struct tmps *restore;
{
	register struct om *op = &sizes[ cbn ];

#	ifdef PC
	    if (restore->reg_off < op->curtmps.reg_off) {
		    op->curtmps.reg_off = restore->reg_off;
	    }
#	endif PC
	if (restore->om_off > op->curtmps.om_off) {
		op->curtmps.om_off = restore->om_off;
#		ifdef PC
		    putlbracket( ftnno , -restore->om_off );
#		endif PC
	}
}

#ifdef PC
#ifdef vax
/*
 * create a save mask for registers which have been used
 * in this level
 */
savmask()
{
	int mask;
	int i;

	mask = RSAVEMASK;
	if (opt('t'))
	        mask |= RUNCHECK;
	for (i = 0; i <= sizes[ cbn ].reg_max; i++)
		mask |= 1 << (FIRSTREG + i);
	return mask;
}
#endif vax
#endif PC