tm.texi (TARGET_IRA_COVER_CLASSES): Define.

gcc/
	* doc/tm.texi (TARGET_IRA_COVER_CLASSES): Define.
	(IRA_COVER_CLASSES): Refer to TARGET_IRA_COVER_CLASSES.
	* target.h (gcc_target): Add ira_cover_classes.
	* ira.c: Remove IRA_COVER_CLASSES guards.
	(setup_cover_and_important_classes): Use targetm.ira_cover_classes
	instead of IRA_COVER_CLASSES.
	(setup_cover_and_important_classes): Remove IRA_COVER_CLASSES guard.
	(setup_class_translate): Likewise.
	(setup_reg_class_intersect_union): Likewise.
	(find_reg_class_closure): Replace IRA_COVER_CLASSES guard with a
	test of targetm.ira_cover_classes.
	* opts.c (decode_options): Use targetm.ira_cover_classes instead
	of IRA_COVER_CLASSES.
	* target-def.h (TARGET_IRA_COVER_CLASSES): Define.
	(TARGET_INITIALIZER): Include it.
	* targhooks.h (default_ira_cover_classes): Declare.
	* targhooks.c (default_ira_cover_classes): New function.

From-SVN: r140512

gcc/ChangeLog

+2008-09-20  Richard Sandiford  <rdsandiford@googlemail.com>
+
+	* doc/tm.texi (TARGET_IRA_COVER_CLASSES): Define.
+	(IRA_COVER_CLASSES): Refer to TARGET_IRA_COVER_CLASSES.
+	* target.h (gcc_target): Add ira_cover_classes.
+	* ira.c: Remove IRA_COVER_CLASSES guards.
+	(setup_cover_and_important_classes): Use targetm.ira_cover_classes
+	instead of IRA_COVER_CLASSES.
+	(setup_cover_and_important_classes): Remove IRA_COVER_CLASSES guard.
+	(setup_class_translate): Likewise.
+	(setup_reg_class_intersect_union): Likewise.
+	(find_reg_class_closure): Replace IRA_COVER_CLASSES guard with a
+	test of targetm.ira_cover_classes.
+	* opts.c (decode_options): Use targetm.ira_cover_classes instead
+	of IRA_COVER_CLASSES.
+	* target-def.h (TARGET_IRA_COVER_CLASSES): Define.
+	(TARGET_INITIALIZER): Include it.
+	* targhooks.h (default_ira_cover_classes): Declare.
+	* targhooks.c (default_ira_cover_classes): New function.
+
 2008-09-19  Bob Wilson  <bob.wilson@acm.org>
 	
 	* config/xtensa/xtensa.md (reload<mode>_literal): Handle MEM operands.

gcc/doc/tm.texi

@@ -2826,17 +2826,26 @@ as below:
 @end smallexample
 @end defmac
 
-@defmac IRA_COVER_CLASSES
-The macro defines cover classes for the Integrated Register Allocator
+@deftypefn {Target Hook} {const enum reg_class *} TARGET_IRA_COVER_CLASSES ()
+Return an array of cover classes for the Integrated Register Allocator
 (@acronym{IRA}).  Cover classes are a set of non-intersecting register
 classes covering all hard registers used for register allocation
 purposes.  If a move between two registers in the same cover class is
 possible, it should be cheaper than a load or store of the registers.
-The macro value should be the initializer for an array of register
-class values, with @code{LIM_REG_CLASSES} used as the end marker.
+The array is terminated by a @code{LIM_REG_CLASSES} element.
+
+This hook is called once at compiler startup, after the command-line
+options have been processed. It is then re-examined by every call to
+@code{target_reinit}.
 
-You must define this macro in order to use the integrated register
+The default implementation returns @code{IRA_COVER_CLASSES}, if defined,
+otherwise there is no default implementation.  You must define either this
+macro or @code{IRA_COVER_CLASSES} in order to use the integrated register
 allocator for the target.
+@end deftypefn
+
+@defmac IRA_COVER_CLASSES
+See the documentation for @code{TARGET_IRA_COVER_CLASSES}.
 @end defmac
 
 @node Old Constraints

gcc/ira.c

@@ -714,8 +714,6 @@ enum reg_class ira_important_classes[N_REG_CLASSES];
    classes.  */
 int ira_important_class_nums[N_REG_CLASSES];
 
-#ifdef IRA_COVER_CLASSES
-
 /* Check IRA_COVER_CLASSES and sets the four global variables defined
    above.  */
 static void
@@ -723,9 +721,10 @@ setup_cover_and_important_classes (void)
 {
   int i, j;
   enum reg_class cl;
-  static enum reg_class classes[] = IRA_COVER_CLASSES;
+  const enum reg_class *classes;
   HARD_REG_SET temp_hard_regset2;
 
+  classes = targetm.ira_cover_classes ();
   ira_reg_class_cover_size = 0;
   for (i = 0; (cl = classes[i]) != LIM_REG_CLASSES; i++)
     {
@@ -761,15 +760,12 @@ setup_cover_and_important_classes (void)
 	  }
     }
 }
-#endif
 
 /* Map of all register classes to corresponding cover class containing
    the given class.  If given class is not a subset of a cover class,
    we translate it into the cheapest cover class.  */
 enum reg_class ira_class_translate[N_REG_CLASSES];
 
-#ifdef IRA_COVER_CLASSES
-
 /* Set up array IRA_CLASS_TRANSLATE.  */
 static void
 setup_class_translate (void)
@@ -837,7 +833,6 @@ setup_class_translate (void)
       ira_class_translate[cl] = best_class;
     }
 }
-#endif
 
 /* The biggest important reg_class inside of intersection of the two
    reg_classes (that is calculated taking only hard registers
@@ -856,8 +851,6 @@ enum reg_class ira_reg_class_intersect[N_REG_CLASSES][N_REG_CLASSES];
    reg_class_subunion value.  */
 enum reg_class ira_reg_class_union[N_REG_CLASSES][N_REG_CLASSES];
 
-#ifdef IRA_COVER_CLASSES
-
 /* Set up IRA_REG_CLASS_INTERSECT and IRA_REG_CLASS_UNION.  */
 static void
 setup_reg_class_intersect_union (void)
@@ -943,8 +936,6 @@ setup_reg_class_intersect_union (void)
     }
 }
 
-#endif
-
 /* Output all cover classes and the translation map into file F.  */
 static void
 print_class_cover (FILE *f)
@@ -975,11 +966,12 @@ static void
 find_reg_class_closure (void)
 {
   setup_reg_subclasses ();
-#ifdef IRA_COVER_CLASSES
-  setup_cover_and_important_classes ();
-  setup_class_translate ();
-  setup_reg_class_intersect_union ();
-#endif
+  if (targetm.ira_cover_classes)
+    {
+      setup_cover_and_important_classes ();
+      setup_class_translate ();
+      setup_reg_class_intersect_union ();
+    }
 }
 
 

gcc/opts.c

@@ -870,10 +870,9 @@ decode_options (unsigned int argc, const char **argv)
 	}
     }
   
-#ifdef IRA_COVER_CLASSES
   /* Use IRA if it is implemented for the target.  */
-  flag_ira = 1;
-#endif
+  if (targetm.ira_cover_classes)
+    flag_ira = 1;
 
   /* -O1 optimizations.  */
   opt1 = (optimize >= 1);
@@ -1097,13 +1096,11 @@ decode_options (unsigned int argc, const char **argv)
   if (!flag_sel_sched_pipelining)
     flag_sel_sched_pipelining_outer_loops = 0;
 
-#ifndef IRA_COVER_CLASSES
-  if (flag_ira)
+  if (flag_ira && !targetm.ira_cover_classes)
     {
       inform (input_location, "-fira does not work on this architecture");
       flag_ira = 0;
     }
-#endif
 
   /* Save the current optimization options if this is the first call.  */
   if (first_time_p)

gcc/target-def.h

@@ -631,6 +631,12 @@
 #define TARGET_HANDLE_PRAGMA_EXTERN_PREFIX 0
 #endif
 
+#ifdef IRA_COVER_CLASSES
+#define TARGET_IRA_COVER_CLASSES default_ira_cover_classes
+#else
+#define TARGET_IRA_COVER_CLASSES 0
+#endif
+
 #ifndef TARGET_SECONDARY_RELOAD
 #define TARGET_SECONDARY_RELOAD default_secondary_reload
 #endif
@@ -907,6 +913,7 @@
   TARGET_INVALID_CONVERSION,			\
   TARGET_INVALID_UNARY_OP,			\
   TARGET_INVALID_BINARY_OP,			\
+  TARGET_IRA_COVER_CLASSES,			\
   TARGET_SECONDARY_RELOAD,			\
   TARGET_EXPAND_TO_RTL_HOOK,			\
   TARGET_INSTANTIATE_DECLS,			\

gcc/target.h

@@ -899,6 +899,9 @@ struct gcc_target
      is not permitted on TYPE1 and TYPE2, NULL otherwise.  */
   const char *(*invalid_binary_op) (int op, const_tree type1, const_tree type2);
 
+  /* Return the array of IRA cover classes for the current target.  */
+  const enum reg_class *(*ira_cover_classes) (void);
+
   /* Return the class for a secondary reload, and fill in extra information.  */
   enum reg_class (*secondary_reload) (bool, rtx, enum reg_class,
 				      enum machine_mode,

gcc/targhooks.c

@@ -575,6 +575,15 @@ default_internal_arg_pointer (void)
     return virtual_incoming_args_rtx;
 }
 
+#ifdef IRA_COVER_CLASSES
+const enum reg_class *
+default_ira_cover_classes (void)
+{
+  static enum reg_class classes[] = IRA_COVER_CLASSES;
+  return classes;
+}
+#endif
+
 enum reg_class
 default_secondary_reload (bool in_p ATTRIBUTE_UNUSED, rtx x ATTRIBUTE_UNUSED,
 			  enum reg_class reload_class ATTRIBUTE_UNUSED,

gcc/targhooks.h

@@ -88,6 +88,9 @@ extern const char *hook_invalid_arg_for_unprototyped_fn
 extern bool hook_bool_const_rtx_commutative_p (const_rtx, int);
 extern rtx default_function_value (const_tree, const_tree, bool);
 extern rtx default_internal_arg_pointer (void);
+#ifdef IRA_COVER_CLASSES
+extern const enum reg_class *default_ira_cover_classes (void);
+#endif
 extern enum reg_class default_secondary_reload (bool, rtx, enum reg_class,
 						enum machine_mode,
 						secondary_reload_info *);