re PR middle-end/28071 (A file that can not be compiled in reasonable time/space)

	PR rtl-optimization/28071
	* tree-cfg.c (tree_split_block): Do not allocate new stmt_list nodes.
	* tree-iterator.c (tsi_split_statement_list_before): Do not crash when
	splitting before first stmt.

From-SVN: r115713

gcc/ChangeLog

 2006-07-24  Jan Hubicka  <jh@suse.cz>
 
 	PR rtl-optimization/28071
+	* tree-cfg.c (tree_split_block): Do not allocate new stmt_list nodes.
+	* tree-iterator.c (tsi_split_statement_list_before): Do not crash when
+	splitting before first stmt.
+
+2006-07-24  Jan Hubicka  <jh@suse.cz>
+
+	PR rtl-optimization/28071
 	* ipa-inline.c (update_caller_keys): Remove edges that
 	are no longer inline candidates.
 

gcc/tree-cfg.c

@@ -4158,7 +4158,8 @@ tree_redirect_edge_and_branch_force (edge e, basic_block dest)
 static basic_block
 tree_split_block (basic_block bb, void *stmt)
 {
-  block_stmt_iterator bsi, bsi_tgt;
+  block_stmt_iterator bsi;
+  tree_stmt_iterator tsi_tgt;
   tree act;
   basic_block new_bb;
   edge e;
@@ -4192,13 +4193,17 @@ tree_split_block (basic_block bb, void *stmt)
 	}
     }
 
-  bsi_tgt = bsi_start (new_bb);
-  while (!bsi_end_p (bsi))
-    {
-      act = bsi_stmt (bsi);
-      bsi_remove (&bsi, false);
-      bsi_insert_after (&bsi_tgt, act, BSI_NEW_STMT);
-    }
+  if (bsi_end_p (bsi))
+    return new_bb;
+
+  /* Split the statement list - avoid re-creating new containers as this
+     brings ugly quadratic memory consumption in the inliner.  
+     (We are still quadratic since we need to update stmt BB pointers,
+     sadly.)  */
+  new_bb->stmt_list = tsi_split_statement_list_before (&bsi.tsi);
+  for (tsi_tgt = tsi_start (new_bb->stmt_list);
+       !tsi_end_p (tsi_tgt); tsi_next (&tsi_tgt))
+    set_bb_for_stmt (tsi_stmt (tsi_tgt), new_bb);
 
   return new_bb;
 }

gcc/tree-iterator.c

@@ -289,7 +289,8 @@ tsi_split_statement_list_before (tree_stmt_iterator *i)
   STATEMENT_LIST_TAIL (new_sl) = STATEMENT_LIST_TAIL (old_sl);
   STATEMENT_LIST_TAIL (old_sl) = prev;
   cur->prev = NULL;
-  prev->next = NULL;
+  if (prev)
+    prev->next = NULL;
 
   return new_sl;
 }