reginfo.c (init_reg_sets): Don't zero globals here.

gcc/
	* reginfo.c (init_reg_sets): Don't zero globals here.  Update comment
	to say that the function can be called more than once.
	* target-globals.c (save_target_globals): Call init_reg_sets.

From-SVN: r162110

gcc/ChangeLog

@@ -1,3 +1,9 @@
+2010-07-12  Richard Sandiford  <rdsandiford@googlemail.com>
+
+	* reginfo.c (init_reg_sets): Don't zero globals here.  Update comment
+	to say that the function can be called more than once.
+	* target-globals.c (save_target_globals): Call init_reg_sets.
+
 2010-07-12  Richard Sandiford  <rdsandiford@googlemail.com>
 
 	* Makefile.in (bb-reorder.o, target-globals.o): Depend on bb-reorder.h

gcc/reginfo.c

@@ -142,8 +142,9 @@ reg_set_to_hard_reg_set (HARD_REG_SET *to, const_bitmap from)
     }
 }
 
-/* Function called only once to initialize the above data on reg usage.
+/* Function called only once per target_globals to initialize the
-   Once this is done, various switches may override.  */
+   target_hard_regs structure.  Once this is done, various switches
+   may override.  */
 void
 init_reg_sets (void)
 {
@@ -186,7 +187,6 @@ init_reg_sets (void)
   memcpy (reg_alloc_order, initial_reg_alloc_order, sizeof reg_alloc_order);
 #endif
   memcpy (reg_names, initial_reg_names, sizeof reg_names);
-  memset (global_regs, 0, sizeof global_regs);
 }
 
 /* Initialize may_move_cost and friends for mode M.  */

gcc/target-globals.c

@@ -80,6 +80,7 @@ save_target_globals (void)
   g->gcse = XCNEW (struct target_gcse);
   g->bb_reorder = XCNEW (struct target_bb_reorder);
   restore_target_globals (g);
+  init_reg_sets ();
   target_reinit ();
   return g;
 }