cfgcleanup bugfix installed

[Jan Hubicka]

Hi,
attached patch fixes 3 problems in the merge_blocks life updating. 
The patch allows me to bootstrap sparc/fixes the regressions on ppc/i386
caused by my previous patch and solves the SH failure I do have.

I've installed it as obvious.

Sat Oct 27 12:01:04 CEST 2001  Jan Hubicka  <jh@suse.cz>

	* cfgcleanup.c (merge_blocks_move_predecessor_nojumps,
	merge_blocks_move_successors_nojumps): Set BB_UPDATE_LIFE.
	(merge_blocks): Properly udpate life after making edge nonfallthru.
	* cfgrtl.c (merge_blocks_nomove): Update global_live_at_end.

Index: cfgcleanup.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/cfgcleanup.c,v
retrieving revision 1.12
diff -c -3 -p -r1.12 cfgcleanup.c
*** cfgcleanup.c	2001/10/26 11:16:09	1.12
--- cfgcleanup.c	2001/10/27 09:32:55
*************** merge_blocks_move_predecessor_nojumps (a
*** 334,339 ****
--- 334,340 ----
    /* Scramble the insn chain.  */
    if (a->end != PREV_INSN (b->head))
      reorder_insns_nobb (a->head, a->end, PREV_INSN (b->head));
+   BB_SET_FLAG (a, BB_UPDATE_LIFE);
  
    if (rtl_dump_file)
      {
*************** merge_blocks_move_successor_nojumps (a, 
*** 402,407 ****
--- 403,409 ----
  
    /* Now blocks A and B are contiguous.  Merge them.  */
    merge_blocks_nomove (a, b);
+   BB_SET_FLAG (a, BB_UPDATE_LIFE);
  
    if (rtl_dump_file)
      {
*************** merge_blocks (e, b, c, mode)
*** 488,497 ****
  
        if (b_has_incoming_fallthru)
  	{
  	  if (b_fallthru_edge->src == ENTRY_BLOCK_PTR)
  	    return false;
! 	  BB_SET_FLAG (b_fallthru_edge, BB_UPDATE_LIFE);
! 	  notice_new_block (force_nonfallthru (b_fallthru_edge));
  	}
        merge_blocks_move_predecessor_nojumps (b, c);
        return true;
--- 490,503 ----
  
        if (b_has_incoming_fallthru)
  	{
+ 	  rtx bb;
  	  if (b_fallthru_edge->src == ENTRY_BLOCK_PTR)
  	    return false;
! 	  bb = force_nonfallthru (b_fallthru_edge);
! 	  if (bb)
! 	    notice_new_block (bb);
! 	  else
! 	    BB_SET_FLAG (b_fallthru_edge->src, BB_UPDATE_LIFE);
  	}
        merge_blocks_move_predecessor_nojumps (b, c);
        return true;
Index: cfgrtl.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/cfgrtl.c,v
retrieving revision 1.4
diff -c -3 -p -r1.4 cfgrtl.c
*** cfgrtl.c	2001/10/11 03:15:24	1.4
--- cfgrtl.c	2001/10/27 09:32:56
*************** merge_blocks_nomove (a, b)
*** 603,608 ****
--- 603,609 ----
  
    /* B hasn't quite yet ceased to exist.  Attempt to prevent mishap.  */
    b->pred = b->succ = NULL;
+   a->global_live_at_end = b->global_live_at_end;
  
    expunge_block (b);