attribute data structure rewrite

[Giovanni Bajo]

Geoffrey Keating wrote:

> /* A structure representing 'attributes' on a DECL or TYPE node.
>     Each attribute has a NAME (an IDENTIFIER_NODE) and possibly a
>   VALUE. */
> struct one_attribute GTY(())
> {
>    tree name;
>    tree value;
> };
> 
> /* A counted list of attributes.  */
> struct attribute_list_s GTY(())
> {
>    attribute_count n_attributes;
>    /* There are 16 bits free here.  */
>    struct one_attribute GTY((length ("%h.n_attributes"))) attribs[1];
> };

Why not simply VEC(one_attribute) ?

Do you have some numbers on the speedup we get with this?

Giovanni Bajo