flow.c (merge_blocks_move_predecessor_nojumps): Cope with already adjacent blocks, but no fallthru.

        * flow.c (merge_blocks_move_predecessor_nojumps): Cope
        with already adjacent blocks, but no fallthru.
        (merge_blocks_move_successor_nojumps): Simplify.
        (debug_flow_info): New.

From-SVN: r30203

gcc/ChangeLog

+Tue Oct 26 20:21:02 1999  Richard Henderson  <rth@cygnus.com>
+
+	* flow.c (merge_blocks_move_predecessor_nojumps): Cope
+	with already adjacent blocks, but no fallthru.
+	(merge_blocks_move_successor_nojumps): Simplify.
+	(debug_flow_info): New.
+
+	* toplev.c (rest_of_compilation): Open jump1 dump file before
+	jump and close after, as opposed to just using dump_rtl.
+
 Wed Oct 27 03:09:23 1999  J"orn Rennecke <amylaar@cygnus.co.uk>
 
 	* reload.h (earlyclobber_operand_p): Declare.

gcc/flow.c

@@ -2011,12 +2011,11 @@ static int
 merge_blocks_move_predecessor_nojumps (a, b)
      basic_block a, b;
 {
-  rtx start, end, insertpoint, barrier;
+  rtx start, end, barrier;
   int index;
 
   start = a->head;
   end = a->end;
-  insertpoint = PREV_INSN (b->head);
 
   /* We want to delete the BARRIER after the end of the insns we are
      going to move.  If we don't find a BARRIER, then do nothing.  This
@@ -2042,7 +2041,8 @@ merge_blocks_move_predecessor_nojumps (a, b)
   start = squeeze_notes (start, end);
 
   /* Scramble the insn chain.  */
-  reorder_insns (start, end, insertpoint);
+  if (end != PREV_INSN (b->head))
+    reorder_insns (start, end, PREV_INSN (b->head));
 
   if (rtl_dump_file)
     {
@@ -2073,11 +2073,10 @@ static int
 merge_blocks_move_successor_nojumps (a, b)
      basic_block a, b;
 {
-  rtx start, end, insertpoint, barrier;
+  rtx start, end, barrier;
 
   start = b->head;
   end = b->end;
-  insertpoint = a->end;
 
   /* We want to delete the BARRIER after the end of the insns we are
      going to move.  If we don't find a BARRIER, then do nothing.  This
@@ -2103,7 +2102,7 @@ merge_blocks_move_successor_nojumps (a, b)
   start = squeeze_notes (start, end);
 
   /* Scramble the insn chain.  */
-  reorder_insns (start, end, insertpoint);
+  reorder_insns (start, end, a->end);
 
   /* Now blocks A and B are contiguous.  Merge them.  */
   merge_blocks_nomove (a, b);
@@ -4966,6 +4965,12 @@ dump_flow_info (file)
   putc('\n', file);
 }
 
+void
+debug_flow_info ()
+{
+  dump_flow_info (stderr);
+}
+
 static void
 dump_edge_info (file, e, do_succ)
      FILE *file;