Re: [PATCH] pickles: Update btf.pk

[David Faust]

On 12/15/21 22:35, Jose E. Marchesi wrote:
> Hi David.
>
> > Update BTF pickle with recent additions/changes to the format:
> > - BTF_KIND_DATASEC uses 'size' not 'type'
> > - Add BTF_KIND_FLOAT
> > - Add BTF_KIND_DECL_TAG and BTF_KIND_TYPE_TAG
> >
> > 2021-12-15  David Faust  <david.faust@oracle.com>
> >
> >         * pickles/btf.pk (BTF_KIND_FLOAT): New kind.
> >         (BTF_KIND_DECL_TAG): Likewise.
> >         (BTF_KIND_TYPE_TAG): Likewise.
> >         (BTF_Decl_Tag): New type.
> >         (BTF_Type): Update `info` bits usage to accomodate new type kinds.
> >         BTF_KIND_DATASEC uses `size` variant of `attrs`.
> >         Add `decl_tag` variant to `data`.
> > ---
> >   ChangeLog      | 10 ++++++++++
> >   pickles/btf.pk | 24 +++++++++++++++++++-----
> >   2 files changed, 29 insertions(+), 5 deletions(-)
> >
> > diff --git a/pickles/btf.pk b/pickles/btf.pk
> > index 4832ada6..a23944db 100644
> > --- a/pickles/btf.pk
> > +++ b/pickles/btf.pk
> > @@ -35,12 +35,15 @@ var BTF_KIND_UNKNOWN = 0,
> >       BTF_KIND_FUNC = 12,
> >       BTF_KIND_FUNC_PROTO = 13,
> >       BTF_KIND_VAR = 14,
> > -    BTF_KIND_DATASEC = 15;
> > +    BTF_KIND_DATASEC = 15,
> > +    BTF_KIND_FLOAT = 16,
> > +    BTF_KIND_DECL_TAG = 17,
> > +    BTF_KIND_TYPE_TAG = 18;
> >   
> >   var btf_kind_names =
> >     ["unkn", "int", "ptr", "array", "struct", "union", "enum",
> >      "fwd", "typedef", "volatile", "const", "restrict", "func",
> > -   "func_proto", "var", "datasec"];
> > +   "func_proto", "var", "datasec", "float", "decl_tag", "type_tag"];
> >   
> >   type BTF_Type_Id = uint<32>;
> >   
> > @@ -100,6 +103,14 @@ type BTF_Var_SecInfo =
> >       offset<uint<32>,B> size;
> >     };
> >   
> > +type BTF_Decl_Tag =
> > +  struct
> > +  {
> > +    /* -1 if the tag is applied to the type itself,
> > +       else the index of the tagged field/parameter/etc.  */
> > +    uint<32> component_idx;
> > +  };
>
> Wouldn't that be 0xffff_ffff instead of -1?  In any case, it may be
> useful for the user to have a variable like BTF_DECL_TAG_SELF defined to
> this special value.

Thanks for pointing this out. Of course -1 doesn't make much sense here.

After double checking, this should indeed be a _signed_ int32. Looks 
like a small error in the format documentation which refers to it as 
unsigned (while also using the -1).

Fixed, added BTF_DECL_TAG_SELF, and pushed.
Thanks!

> Other than that, the patch is OK for master.
> Thanks.