[v4,3/4] reggroups: Add reggroup_gdbarch_new, reggroup_find for dynamic reggroups

  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.

Also creating reggroup_find() as a utility to find a gdbarch registered
reggroup object by name.

gdb/ChangeLog:

yyyy-mm-dd  Stafford Horne  <shorne@gmail.com>

	* reggroups.c (reggroup_gdbarch_new): New function.
	(reggroup_find): New function.
	* reggroups.h (reggroup_gdbarch_new): New function.
	(reggroup_find): New function.
---
Changes since v3
 * Added the reggroup_find function.

 gdb/reggroups.c | 29 +++++++++++++++++++++++++++++
 gdb/reggroups.h |  5 +++++
 2 files changed, 34 insertions(+)
  

On 2017-12-26 08:48 AM, Stafford Horne wrote:
> 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.
> 
> Also creating reggroup_find() as a utility to find a gdbarch registered
> reggroup object by name.
> 
> gdb/ChangeLog:
> 
> yyyy-mm-dd  Stafford Horne  <shorne@gmail.com>
> 
> 	* reggroups.c (reggroup_gdbarch_new): New function.
> 	(reggroup_find): New function.
> 	* reggroups.h (reggroup_gdbarch_new): New function.
> 	(reggroup_find): New function.
> ---
> Changes since v3
>  * Added the reggroup_find function.
> 
>  gdb/reggroups.c | 29 +++++++++++++++++++++++++++++
>  gdb/reggroups.h |  5 +++++
>  2 files changed, 34 insertions(+)
> 
> diff --git a/gdb/reggroups.c b/gdb/reggroups.c
> index 5d5e33f2a3..4e6b452f88 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 *
> @@ -201,6 +213,23 @@ default_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
>    return 0;   
>  }
>  
> +/* Find a reggroup by name.  */
> +
> +reggroup *
> +reggroup_find (struct gdbarch *gdbarch, const char *name)
> +{
> +  struct reggroup *group;
> +
> +  for (group = reggroup_next (gdbarch, NULL);
> +       group != NULL;
> +       group = reggroup_next (gdbarch, group))
> +    {
> +      if (strcmp (name, reggroup_name (group)) == 0)
> +	return group;
> +    }
> +  return NULL;
> +}
> +
>  /* Dump out a table of register groups for the current architecture.  */
>  
>  static void
> diff --git a/gdb/reggroups.h b/gdb/reggroups.h
> index 18fc1bf294..5cfa51abff 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);
> @@ -57,6 +61,7 @@ extern struct reggroup *reggroup_next (struct gdbarch *gdbarch,
>  				       struct reggroup *last);
>  extern struct reggroup *reggroup_prev (struct gdbarch *gdbarch,
>  				       struct reggroup *curr);
> +extern reggroup *reggroup_find (struct gdbarch *gdbarch, const char *name);

Please add a doc comment for this declaration.  In the .c, write

  /* See reggroups.h.  */

for both functions.

It's ok to push with that fixed.

Simon