more rtvec fixes

[Jeffrey A Law <law at cygnus dot com>]

The garbage collection code assumed that an rtvec was an array of rtunions
instead of an array of rtxs.  This was causing a variety of unpleasant
problems.


	* ggc-none.c (ggc_alloc_rtvec): An rtvec is an array of rtx,
	not an array of rtunion.
	* ggc-page.c (ggc_alloc_rtvec): Similarly.
	* ggc-simple (ggc_free_rtvec): Similarly.

Index: ggc-none.c
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/ggc-none.c,v
retrieving revision 1.4
diff -c -3 -p -r1.4 ggc-none.c
*** ggc-none.c	1999/09/11 19:50:42	1.4
--- ggc-none.c	1999/10/04 06:12:31
*************** rtvec
*** 51,57 ****
  ggc_alloc_rtvec (nelt)
       int nelt;
  {
!   int size = sizeof (struct rtvec_def) + (nelt - 1) * sizeof (rtunion);
    rtvec v;
  
    v = (rtvec) xmalloc (size);
--- 51,57 ----
  ggc_alloc_rtvec (nelt)
       int nelt;
  {
!   int size = sizeof (struct rtvec_def) + (nelt - 1) * sizeof (rtx);
    rtvec v;
  
    v = (rtvec) xmalloc (size);
Index: ggc-page.c
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/ggc-page.c,v
retrieving revision 1.3
diff -c -3 -p -r1.3 ggc-page.c
*** ggc-page.c	1999/09/29 23:08:11	1.3
--- ggc-page.c	1999/10/04 06:12:32
*************** ggc_alloc_rtvec (nelt)
*** 795,801 ****
       int nelt;
  {
    return (struct rtvec_def *)
!     alloc_obj (sizeof (struct rtvec_def) + (nelt - 1) * sizeof (rtunion), 1);
  }
  
  
--- 795,801 ----
       int nelt;
  {
    return (struct rtvec_def *)
!     alloc_obj (sizeof (struct rtvec_def) + (nelt - 1) * sizeof (rtx), 1);
  }
  
  
Index: ggc-simple.c
===================================================================
RCS file: /egcs/carton/cvsfiles/egcs/gcc/ggc-simple.c,v
retrieving revision 1.19
diff -c -3 -p -r1.19 ggc-simple.c
*** ggc-simple.c	1999/09/22 05:51:43	1.19
--- ggc-simple.c	1999/10/04 06:12:33
*************** ggc_free_rtvec (v)
*** 366,372 ****
  #endif
  #ifdef GGC_POISON
    memset (v, 0xBB, sizeof (*v) + ((GET_NUM_ELEM (&v->vec) - 1)
! 				  * sizeof (rtunion)));
  #endif
  
    free (v);
--- 366,372 ----
  #endif
  #ifdef GGC_POISON
    memset (v, 0xBB, sizeof (*v) + ((GET_NUM_ELEM (&v->vec) - 1)
! 				  * sizeof (rtx)));
  #endif
  
    free (v);