[PATCH v2 3/4] reggroups: Create reggroup_gdbarch_new for dynamic reggroups

[Stafford Horne <shorne@gmail.com>]

Traditionally reggroups have been created via reggroup_new() during
initialization code and never freed.  Now, if we want to initialize
reggroups dynamically (i.e. in target description) we should be able to
free them.  Create this function reggroup_gdbarch_new() which will
allocate the reggroup memory onto the passed gdbarch obstack.

gdb/ChangeLog:

2017-06-10  Stafford Horne  <shorne@gmail.com>

	* reggroups.c (reggroup_gdbarch_new): New function.
	* reggroups.h (reggroup_gdbarch_new): New function.
---
 gdb/reggroups.c | 12 ++++++++++++
 gdb/reggroups.h |  4 ++++
 2 files changed, 16 insertions(+)

diff --git a/gdb/reggroups.c b/gdb/reggroups.c
index bf40964..c7126f7 100644
--- a/gdb/reggroups.c
+++ b/gdb/reggroups.c
@@ -46,6 +46,18 @@ reggroup_new (const char *name, enum reggroup_type type)
   return group;
 }
 
+struct reggroup *
+reggroup_gdbarch_new (struct gdbarch *gdbarch, const char *name,
+		      enum reggroup_type type)
+{
+  struct reggroup *group = GDBARCH_OBSTACK_ZALLOC (gdbarch,
+						   struct reggroup);
+
+  group->name = gdbarch_obstack_strdup (gdbarch, name);
+  group->type = type;
+  return group;
+}
+
 /* Register group attributes.  */
 
 const char *
diff --git a/gdb/reggroups.h b/gdb/reggroups.h
index 18fc1bf..c1653cd 100644
--- a/gdb/reggroups.h
+++ b/gdb/reggroups.h
@@ -41,6 +41,10 @@ extern struct reggroup *const restore_reggroup;
 /* Create a new local register group.  */
 extern struct reggroup *reggroup_new (const char *name,
 				      enum reggroup_type type);
+/* Create a new register group allocated onto the gdbarch obstack.  */
+extern struct reggroup *reggroup_gdbarch_new (struct gdbarch *gdbarch,
+					      const char *name,
+					      enum reggroup_type type);
 
 /* Add a register group (with attribute values) to the pre-defined list.  */
 extern void reggroup_add (struct gdbarch *gdbarch, struct reggroup *group);
-- 
2.9.4