Re: patch for flow.c: flow_delete_insn

[Richard Henderson <rth at cygnus dot com>]

On Tue, May 09, 2000 at 03:19:55PM -0700, Richard Henderson wrote:
> Alternately, use reorder_insns, or just create a new note.

This implements the former.  Bootstrapped alphaev56 and i686 linux.


r~

        * flow.c (find_basic_blocks_1): Do not delete the first
        bb_note we run across.
        (create_basic_block): Use reorder_insns to move an existing
        bb_note to the correct place.

Index: flow.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/flow.c,v
retrieving revision 1.281
diff -c -p -d -r1.281 flow.c
*** flow.c	2000/05/09 18:41:25	1.281
--- flow.c	2000/05/10 05:47:04
*************** find_basic_blocks_1 (f)
*** 584,591 ****
  	      {
  		if (bb_note == NULL_RTX)
  		  bb_note = insn;
! 
! 		next = flow_delete_insn (insn);
  	      }
  	    break;
  	  }
--- 584,591 ----
  	      {
  		if (bb_note == NULL_RTX)
  		  bb_note = insn;
! 		else
! 		  next = flow_delete_insn (insn);
  	      }
  	    break;
  	  }
*************** create_basic_block (index, head, end, bb
*** 780,792 ****
      {
        /* If we found an existing note, thread it back onto the chain.  */
  
        if (GET_CODE (head) == CODE_LABEL)
! 	add_insn_after (bb_note, head);
        else
  	{
! 	  add_insn_before (bb_note, head);
  	  head = bb_note;
  	}
      }
    else
      {
--- 780,797 ----
      {
        /* If we found an existing note, thread it back onto the chain.  */
  
+       rtx after;
+ 
        if (GET_CODE (head) == CODE_LABEL)
! 	after = head;
        else
  	{
! 	  after = PREV_INSN (head);
  	  head = bb_note;
  	}
+ 
+       if (after != bb_note && NEXT_INSN (after) != bb_note)
+ 	reorder_insns (bb_note, bb_note, after);
      }
    else
      {