* Makefile.in (arm-tdep.o, eval.o, target-descriptions.o)

	(xml-tdesc.o): Update.
	* xml-support.c: Add a comment.
	(gdb_xml_enums_boolean): New variable.
	(gdb_xml_parse_attr_enum): Use strcasecmp.
	* xml-support.h (gdb_xml_enums_boolean): Declare.
	* xml-tdesc.c (struct tdesc_parsing_data): Record current_feature,
	next_regnum, and current_union.
	(tdesc_start_feature, tdesc_start_reg, tdesc_start_union)
	(tdesc_end_union, tdesc_start_field, tdesc_start_vector)
	(field_attributes, union_children, reg_attributes, union_attributes)
	(vector_attributes, feature_attributes, feature_children): New.
	(target_children): Make static.  Add <feature>.
	(tdesc_elements): Make static.
	* target-descriptions.c (struct tdesc_reg, tdesc_reg_p, type_p)
	(struct tdesc_feature, tdesc_feature_p): New types.
	(struct target_desc): Add features member.
	(struct tdesc_arch_data, tdesc_data): New.
	(target_find_description): Clarify error message.  Warn about
	ignored register descriptions.
	(tdesc_has_registers, tdesc_find_feature, tdesc_feature_name)
	(tdesc_named_type, tdesc_data_init, tdesc_data_alloc)
	(tdesc_data_cleanup, tdesc_numbered_register)
	(tdesc_numbered_register_choices, tdesc_find_register)
	(tdesc_register_name, tdesc_register_type)
	(tdesc_remote_register_number, tdesc_register_reggroup_p)
	(set_tdesc_pseudo_register_name, set_tdesc_pseudo_register_type)
	(set_tdesc_pseudo_register_reggroup_p, tdesc_use_registers)
	(tdesc_free_reg, tdesc_create_reg, tdesc_free_feature)
	(tdesc_create_feature, tdesc_record_type): New.
	(free_target_description): Free features.
	(_initialize_target_descriptions): Initialize tdesc_data.
	* arch-utils.c (default_remote_register_number): New.
	* arch-utils.h (default_remote_register_number): New prototype.
	* target-descriptions.h (set_tdesc_pseudo_register_name)
	(set_tdesc_pseudo_register_type, set_tdesc_pseudo_register_reggroup_p)
	(tdesc_use_registers, tdesc_data_alloc, tdesc_data_cleanup)
	(tdesc_numbered_register, tdesc_numbered_register_choices)
	(tdesc_has_registers, tdesc_find_feature, tdesc_feature_name)
	(tdesc_named_type, tdesc_create_feature, tdesc_record_type)
	(tdesc_create_reg): Declare.
	* gdbarch.sh (remote_register_number): New entry.
	* gdbarch.c, gdbarch.h: Regenerate.
	* remote.c (init_remote_state): Use gdbarch_remote_register_number.
	* features/gdb-target.dtd: Add feature, reg, vector, union, and field.

	* arm-tdep.c (arm_register_aliases): New.
	(arm_register_name_strings): Rename to...
	(arm_register_names): ...this.  Make const.  Delete the old version.
	(current_option, arm_register_byte): Delete.
	(set_disassembly_style): Simplify.  Do not adjust arm_register_names.
	(value_of_arm_user_reg): New.
	(arm_gdbarch_init): Verify any described registers.  Call
	tdesc_use_registers.  Don't use arm_register_byte.  Create aliases
	for standard register names.
	(_initialize_arm_tdep): Do not adjust arm_register_names.
	* user-regs.c (struct user_reg): Add baton member.
	(append_user_reg, user_reg_add_builtin, user_regs_init)
	(user_reg_add, value_of_user_reg): Use a baton for user
	register functions.
	* std-regs.c: Update.
	* user-regs.h (user_reg_read_ftype, user_reg_add_builtin)
	(user_reg_add): Add baton argument.
	* NEWS: Mention target description register support.
	* features/arm-core.xml, features/arm-fpa.xml: New.
	* eval.c (evaluate_subexp_standard): Allow ptype $register
	when the program is not running.

	* gdb.texinfo (-target-disconnect): Use @smallexample.
	(Requirements): Add anchor for Expat.  Update description.
	(Target Descriptions): Mention Expat.
	(Target Description Format): Document new elements.  Use
	@smallexample.
	(Predefined Target Types, Standard Target Features): New sections.
	* doc/gdbint.texinfo (Target Descriptions): New section.

	* gdb.xml/single-reg.xml, gdb.xml/tdesc-regs.exp,
	gdb.xml/core-only.xml, gdb.xml/extra-regs.xml: New files.

1 files changed, 92 insertions, 1 deletions

diff --git a/gdb/target-descriptions.h b/gdb/target-descriptions.h
index f45e53be23c..9c641903e57 100644
--- a/gdb/target-descriptions.h
+++ b/gdb/target-descriptions.h
@@ -24,7 +24,12 @@
 #ifndef TARGET_DESCRIPTIONS_H
 #define TARGET_DESCRIPTIONS_H 1
 
+struct tdesc_feature;
+struct tdesc_arch_data;
+struct tdesc_reg;
 struct target_desc;
+struct target_ops;
+struct type;
 
 /* Fetch the current target's description, and switch the current
    architecture to one which incorporates that description.  */
@@ -42,6 +47,65 @@ void target_clear_description (void);
 
 const struct target_desc *target_current_description (void);
 
+/* Record architecture-specific functions to call for pseudo-register
+   support.  If tdesc_use_registers is called and NUM_PSEUDO_REGS
+   is greater than zero, then these should be called as well.
+   They are equivalent to the gdbarch methods with similar names,
+   except that they will only be called for pseudo registers.  */
+
+void set_tdesc_pseudo_register_name
+  (struct gdbarch *gdbarch, gdbarch_register_name_ftype *pseudo_name);
+
+void set_tdesc_pseudo_register_type
+  (struct gdbarch *gdbarch, gdbarch_register_type_ftype *pseudo_type);
+
+void set_tdesc_pseudo_register_reggroup_p
+  (struct gdbarch *gdbarch,
+   gdbarch_register_reggroup_p_ftype *pseudo_reggroup_p);
+
+/* Update GDBARCH to use the target description for registers.  Fixed
+   register assignments are taken from EARLY_DATA, which is freed.
+   All registers which have not been assigned fixed numbers are given
+   numbers above the current value of NUM_REGS.  NUM_REGS and various
+   register-related predicates are updated to refer to the target
+   description.  This function should only be called from the
+   architecture's gdbarch initialization routine, and only after
+   successfully validating the required registers.  */
+
+void tdesc_use_registers (struct gdbarch *gdbarch,
+			  struct tdesc_arch_data *early_data);
+
+/* Allocate initial data for validation of a target description during
+   gdbarch initialization.  */
+
+struct tdesc_arch_data *tdesc_data_alloc (void);
+
+/* Clean up data allocated by tdesc_data_alloc.  This should only
+   be called to discard the data; tdesc_use_registers takes ownership
+   of its EARLY_DATA argument.  */
+
+void tdesc_data_cleanup (void *data_untyped);
+
+/* Search FEATURE for a register named NAME.  Record REGNO and the
+   register in DATA; when tdesc_use_registers is called, REGNO will be
+   assigned to the register.  1 is returned if the register was found,
+   0 if it was not.  */
+
+int tdesc_numbered_register (const struct tdesc_feature *feature,
+			     struct tdesc_arch_data *data,
+			     int regno, const char *name);
+
+/* Search FEATURE for a register with any of the names from NAMES
+   (NULL-terminated).  Record REGNO and the register in DATA; when
+   tdesc_use_registers is called, REGNO will be assigned to the
+   register.  1 is returned if the register was found, 0 if it was
+   not.  */
+
+int tdesc_numbered_register_choices (const struct tdesc_feature *feature,
+				     struct tdesc_arch_data *data,
+				     int regno, const char *const names[]);
+
+
 /* Accessors for target descriptions.  */
 
 /* Return the BFD architecture associated with this target
@@ -56,14 +120,41 @@ const struct bfd_arch_info *tdesc_architecture
 const char *tdesc_property (const struct target_desc *,
 			    const char *key);
 
+/* Return 1 if this target description describes any registers.  */
+
+int tdesc_has_registers (const struct target_desc *);
+
+/* Return the feature with the given name, if present, or NULL if
+   the named feature is not found.  */
+
+const struct tdesc_feature *tdesc_find_feature (const struct target_desc *,
+						const char *name);
+
+/* Return the name of FEATURE.  */
+
+const char *tdesc_feature_name (const struct tdesc_feature *feature);
+
+/* Return the type associated with ID in the context of FEATURE, or
+   NULL if none.  */
+
+struct type *tdesc_named_type (const struct tdesc_feature *feature,
+			       const char *id);
+
 /* Methods for constructing a target description.  */
 
 struct target_desc *allocate_target_description (void);
 struct cleanup *make_cleanup_free_target_description (struct target_desc *);
 void set_tdesc_architecture (struct target_desc *,
 			     const struct bfd_arch_info *);
-
 void set_tdesc_property (struct target_desc *,
 			 const char *key, const char *value);
 
+struct tdesc_feature *tdesc_create_feature (struct target_desc *tdesc,
+					    const char *name);
+void tdesc_record_type (struct tdesc_feature *feature, struct type *type);
+
+void tdesc_create_reg (struct tdesc_feature *feature, const char *name,
+		       int regnum, int save_restore, const char *group,
+		       int bitsize, const char *type);
+
 #endif /* TARGET_DESCRIPTIONS_H */