/*
 * Copyright (c) 1998,1999 David Stes.
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Library General Public License as published 
 * by the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Id: rtrnstmt.m,v 1.2 2000/09/10 09:18:44 stes Exp $
 */

#include "config.h"
#include <stdlib.h>
#include <assert.h>
#ifndef __OBJECT_INCLUDED__
#define __OBJECT_INCLUDED__
#include <stdio.h> /* FILE */
#include "Object.h" /* Stepstone Object.h assumes #import */
#endif
#include "node.h"
#include "stmt.h"
#include "expr.h"
#include "type.h"
#include "rtrnstmt.h"
#include "compstmt.h"
#include "classdef.h"
#include "options.h"
#include "def.h"
#include "methdef.h"
#include "stkframe.h"

@implementation ReturnStmt

- keyw:aKeyw
{
  keyw = aKeyw;
  return self;
}

- expr:anExpr
{
  expr = anExpr;
  return self;
}

- synth
{
  id c;

  for (c = curcompound; c; c = [c enclosing]) {
    if ([c isblockexpr]) {
      fatalat(keyw, "non-local return from within block not yet supported");
    }
  }
  [expr synth];
  if (o_refcnt) {
    if (expr) {
      id t = [expr type];

      if (![expr isconstexpr] && [t isid])
	incretval++;
      /* self is a bit special but must also be incref'ed */
      else if (curclassdef) {
	/* the following works in factory and instance case */
	if (curdef && [curdef ismethdef]) {
	  if ([t isEqual:[curclassdef selftype]])
	    incretval++;
	}
      }
    }

    compound = curcompound;
    [compound usereturnflag];
  }

  return self;
}

- gen
{
  id label;
  if (o_refcnt && (label=[compound nextreturnlabel]) != nil) {
    if (keyw) {
      gl([keyw lineno],[[keyw filename] str]);
    }
    gs("if (_returnflag==0) {_returnflag++;");
    if (expr) {
      gs("_returnval=");
      [expr gen];
      gc(';');
    }
    if (incretval) {
      gs("idincref(_returnval);");
    }
    gf("goto %s;}", [label str]);
  } else {
    if (keyw)
      [keyw gen];
    else
      gs("return");
    if (expr)
      [expr gen];
    gc(';');
  }
  return self;
}

- st80
{
  gc('^');
  if (expr)
    [expr st80];
  else
    [e_self st80];
  gs(".\n");
  return self;
}

- go
{
  [topframe quitframe:YES];
  if (expr) [topframe returnval:[expr go]];
  return self;
}

@end