#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include "param.h"
#include "tables.h"

#ifdef REGVARS

#ifndef NORCSID
static char rcsid[] = "$Id$";
#endif

#include "types.h"
#include <cgg_cg.h>
#include "data.h"
#include "regvar.h"
#include <em_reg.h>
#include "result.h"
#include "extern.h"

/*
 * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
 * See the copyright notice in the ACK home directory, in the file "Copyright".
 *
 * Author: Hans van Staveren
 */
static struct regvar *rvlist;

struct regvar *linkreg(long of, int sz, int tp, int sc) {
	struct regvar *rvlp;

	rvlp= (struct regvar *) myalloc(sizeof *rvlp);
	rvlp->rv_next = rvlist;
	rvlist=rvlp;
	rvlp->rv_off	= of;
	rvlp->rv_size	= sz;
	rvlp->rv_type	= tp;
	rvlp->rv_score	= sc;
	rvlp->rv_reg	= 0;	/* no register assigned yet */
	return(rvlp);
}

void tryreg(struct regvar *rvlp, int typ) {
	int score;
	int i;
	struct regassigned *ra;
	struct regvar *save;

	if (typ != reg_any && nregvar[typ]!=0) {
		struct reginfo *ri = &machregs[rvnumbers[typ][0]];
		int size, wrong;

		size = ri->r_size;
		wrong = (size!=rvlp->rv_size);
#ifdef REGLAP
		/* reg_float may have one subregister */
		if (wrong && ri->r_members[0]!=0) {
			size = machregs[ri->r_members[0]].r_size;
			wrong = (size!=rvlp->rv_size);
		}
#endif /* REGLAP */
		if (wrong)
			score = -1;
		else
			score = regscore(rvlp->rv_off,
					 rvlp->rv_size,
					 rvlp->rv_type,
					 rvlp->rv_score,
					 typ);	/* machine dependent */
		ra = regassigned[typ];
		if (score>ra[nregvar[typ]-1].ra_score) {
			save = ra[nregvar[typ]-1].ra_rv;
			for (i=nregvar[typ]-1;i>0 && ra[i-1].ra_score<score;i--)
				ra[i] = ra[i-1];
			ra[i].ra_rv = rvlp;
			ra[i].ra_score = score;
			if((rvlp=save)==0)
				return;
		}
	}
	if (nregvar[reg_any]==0)
		return;
	if (machregs[rvnumbers[reg_any][0]].r_size!=rvlp->rv_size)
		score = -1;
	else
		score = regscore(rvlp->rv_off,
				 rvlp->rv_size,
				 rvlp->rv_type,
				 rvlp->rv_score,
				 reg_any);	/* machine dependent */
	ra = regassigned[reg_any];
	if (score>ra[nregvar[reg_any]-1].ra_score) {
		for (i=nregvar[reg_any]-1;i>0 && ra[i-1].ra_score<score;i--)
			ra[i] = ra[i-1];
		ra[i].ra_rv = rvlp;
		ra[i].ra_score = score;
	}
}

void fixregvars(int saveall) {
	struct reginfo *rp, *rp2;
	struct regvar *rv;
	int i, regno, rvtyp;
	
	swtxt();
	i_regsave();	/* machine dependent initialization */
	for (rvtyp=reg_any;rvtyp<=reg_float;rvtyp++) {
	    for(i=0;i<nregvar[rvtyp];i++)
		if (saveall) {
			rp= &machregs[rvnumbers[rvtyp][i]];
#ifdef REGLAP
			/*
			 * A reg_float may have two sizes.  If so,
			 * only save the larger size.
			 */
			if ((regno = rp->r_members[0]) != 0 &&
			    machregs[regno].r_size > rp->r_size)
				rp= &machregs[regno];
#endif
			regsave(codestrings[rp->r_repr],
				    (long)-TEM_WSIZE,rp->r_size);
		} else if(regassigned[rvtyp][i].ra_score>0) {
			rv=regassigned[rvtyp][i].ra_rv;
			rv->rv_reg = regno = rvnumbers[rvtyp][i];
			rv->rv_type = rvtyp;
#ifdef REGLAP
			/*
			 * Change regno to match rv->rv_size, but
			 * leave old regno in rv->rv_reg so that
			 * isregvar_size() can handle both sizes.
			 */
			if (machregs[regno].r_size != rv->rv_size) {
				regno = machregs[regno].r_members[0];
				assert(regno != 0);
				assert(machregs[regno].r_size == rv->rv_size);
			}
#endif
			regsave(codestrings[machregs[regno].r_repr],
				    rv->rv_off,rv->rv_size);
		}
	}
	f_regsave();
}

int isregvar(long off) {
	struct regvar *rvlp;

	for(rvlp=rvlist;rvlp!=0;rvlp=rvlp->rv_next)
		if(rvlp->rv_off == off)
			return(rvlp->rv_reg);
	return(-1);
}

#ifdef REGLAP
int isregvar_size(long off, int size) {
	int regno = isregvar(off);
	/*
	 * A reg_float may have two sizes.  If this register has the
	 * wrong size, then use the overlapping register.  A register
	 * may switch sizes in the middle of a procedure.
	 */
	if (regno > 0 && machregs[regno].r_size != size) {
		if (machregs[regno].r_size != size) {
			regno = machregs[regno].r_members[0];
			assert(regno != 0);
			assert(machregs[regno].r_size == size);
		}
	}
	return regno;
}
#endif /* REGLAP */

int isregtyp(long off) {
	struct regvar *rvlp;

	for (rvlp=rvlist;rvlp!=0;rvlp=rvlp->rv_next)
		if (rvlp->rv_off == off)
			return(rvlp->rv_reg ? rvlp->rv_type+1 : 0);
	return(-1);
}

void unlinkregs(void) {
	struct regvar *rvlp,*t;
	struct regassigned *ra;
	int rvtyp,i;

	for (rvlp=rvlist;rvlp!=0;rvlp=t) {
		t=rvlp->rv_next;
		myfree((string)rvlp);
	}
	rvlist=0;
	for (rvtyp=reg_any;rvtyp<=reg_float;rvtyp++) {
	    for (i=0;i<nregvar[rvtyp];i++) {
		ra= &regassigned[rvtyp][i];
		ra->ra_rv = 0;
		ra->ra_score = 0;
	    }
	}
}

#endif /* REGVARS */

/* nothing after this */