Add some doxygen docu.

[r28145]

ir/be/bearch.h

@@ -235,12 +235,13 @@ void be_register_isa_if(const char *name, const arch_isa_if_t *isa);
  * A register.
  */
 struct arch_register_t {
-	const char                  *name;       /**< The name of the register. */
-	const arch_register_class_t *reg_class;  /**< The class of the register */
-	unsigned short               index;      /**< The index of the register in
-	                                              the class. */
-	unsigned short               global_index;
-	arch_register_type_t         type;       /**< The type of the register. */
+	const char                  *name;         /**< The name of the register. */
+	const arch_register_class_t *reg_class;    /**< The class of the register */
+	unsigned short               index;        /**< The index of the register in
+	                                                the class. */
+	unsigned short               global_index; /** The global index this register
+											       in the architecture. */
+	arch_register_type_t         type;         /**< The type of the register. */
 	/** register constraint allowing just this register */
 	const arch_register_req_t   *single_req;
 };

ir/be/scripts/generate_regalloc_if.pl

@@ -273,14 +273,17 @@ print OUT<<EOF;
 #include "../bearch.h"
 #include "${arch}_nodes_attr.h"
 
+/** global register indices for ${arch} registers */
 enum reg_indices {
 ${regdef}
 	N_${archuc}_REGISTERS
 };
+/** local register indices for ${arch} registers */
 enum {
 ${regdef2}
 };
 
+/** number of registers in ${arch} register classes. */
 enum {
 ${regcounts}
 };
@@ -328,10 +331,14 @@ print OUT "arch_register_class_t ${arch}_reg_classes[] = {\n\t".join(",\n\t", @r
 
 print OUT<<EOF;
 
+/** The array of all registers in the ${arch} architecture, sorted by its global index.*/
 const arch_register_t ${arch}_registers[] = {
 ${regtypes_def}
 };
 
+/**
+ * Initializes ${arch} register classes.
+ */
 void ${arch}_register_init(void)
 {
 ${reginit}