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

	PR rtl-optimization/28071
	* cfgrtl.c (rtl_delete_block): Free regsets.
	* flow.c (allocate_bb_life_data): Re-use regsets if available.

From-SVN: r115810

gcc/ChangeLog

+2006-07-28  Jan Hubicka  <jh@suse.cz>
+
+	PR rtl-optimization/28071
+	* cfgrtl.c (rtl_delete_block): Free regsets.
+	* flow.c (allocate_bb_life_data): Re-use regsets if available.
+
 2006-07-28  Volker Reichelt  <reichelt@igpm.rwth-aachen.de>
 
 	* Makefile.in: Use $(HEADER_H) instead of header.h in dependencies

gcc/cfgrtl.c

@@ -386,6 +386,13 @@ rtl_delete_block (basic_block b)
   /* Selectively delete the entire chain.  */
   BB_HEAD (b) = NULL;
   delete_insn_chain (insn, end);
+  if (b->il.rtl->global_live_at_start)
+    {
+      FREE_REG_SET (b->il.rtl->global_live_at_start);
+      FREE_REG_SET (b->il.rtl->global_live_at_end);
+      b->il.rtl->global_live_at_start = NULL;
+      b->il.rtl->global_live_at_end = NULL;
+    }
 }
 
 /* Records the basic block struct in BLOCK_FOR_INSN for every insn.  */

gcc/flow.c

@@ -1564,8 +1564,16 @@ allocate_bb_life_data (void)
 
   FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
     {
-      bb->il.rtl->global_live_at_start = ALLOC_REG_SET (&reg_obstack);
-      bb->il.rtl->global_live_at_end = ALLOC_REG_SET (&reg_obstack);
+      if (bb->il.rtl->global_live_at_start)
+	{
+	  CLEAR_REG_SET (bb->il.rtl->global_live_at_start);
+	  CLEAR_REG_SET (bb->il.rtl->global_live_at_end);
+	}
+      else
+	{
+	  bb->il.rtl->global_live_at_start = ALLOC_REG_SET (&reg_obstack);
+	  bb->il.rtl->global_live_at_end = ALLOC_REG_SET (&reg_obstack);
+	}
     }
 
   regs_live_at_setjmp = ALLOC_REG_SET (&reg_obstack);