Help implementing support for vec<tree*> in gengtype

[Nicholas Krause]

On 2/27/20 12:56 PM, Giuliano Belinassi wrote:
> Hi, all.
>
> I am tying to fix an issue with a global variable in the parallel gcc
> project. For this, I am trying to move some global variables from
> tree-ssa-operands to struct function. One of this variable is a
> vec<tree*> type, and gengtype doesn't look so happy with it.
>
> In this context, I am trying to add support to vec<tree*> to gengtype.
> Therefore, I first fixed a problem where gengtype couldn't find the
> tree union by:
>
> diff --git a/gcc/gengtype.c b/gcc/gengtype.c
> index 53317337cf8..6f4c77020ea 100644
> --- a/gcc/gengtype.c
> +++ b/gcc/gengtype.c
> @@ -638,7 +638,10 @@ create_user_defined_type (const char *type_name, struct fil
> eloc *pos)
>                /* Strip off the first '*' character (and any subsequent text). */
>                *(field_name + offset_to_star) = '\0';
>   
> -             arg_type = find_structure (field_name, TYPE_STRUCT);
> +             arg_type = resolve_typedef (field_name, pos);
> +             if (!arg_type)
> +               arg_type = find_structure (field_name, TYPE_STRUCT);
> +
>                arg_type = create_pointer (arg_type);
>              }
>            else
>
> After this patch, gengtype seems to correctly detect vec<tree*> types,
> but then I face linking issues. At first, the compiler could not find
> gt_ggc_mx (vec<T> *v) and gt_pch_mx (vec<T> *v), therefore I implemented
> them both in gcc/vec.h:
>
> diff --git a/gcc/vec.h b/gcc/vec.h
> index 091056b37bc..dfa744b684e 100644
> --- a/gcc/vec.h
> +++ b/gcc/vec.h
> @@ -1306,6 +1306,15 @@ vec<T, A, vl_embed>::quick_grow_cleared (unsigned len)
>       vec_default_construct (address () + oldlen, growby);
>   }
>   
> +template<typename T>
> +void
> +gt_ggc_mx (vec<T> *v)
> +{
> +  extern void gt_ggc_mx (T &);
> +  for (unsigned i = 0; i < v->length (); i++)
> +    gt_ggc_mx ((*v)[i]);
> +}
> +
>   /* Garbage collection support for vec<T, A, vl_embed>.  */
>   
>   template<typename T>
> @@ -1328,6 +1337,15 @@ gt_ggc_mx (vec<T, va_gc_atomic, vl_embed> *v ATTRIBUTE_UNUSED)
>   
>   /* PCH support for vec<T, A, vl_embed>.  */
>   
> +template<typename T>
> +void
> +gt_pch_nx (vec<T> *v)
> +{
> +  extern void gt_pch_nx (T &);
> +  for (unsigned i = 0; i < v->length (); i++)
> +    gt_pch_nx ((*v)[i]);
> +}
> +
>   template<typename T, typename A>
>   void
>   gt_pch_nx (vec<T, A, vl_embed> *v)
> @@ -1337,6 +1355,14 @@ gt_pch_nx (vec<T, A, vl_embed> *v)
>       gt_pch_nx ((*v)[i]);
>   }
>   
> +template<typename T>
> +void
> +gt_pch_nx (vec<T *> *v, gt_pointer_operator op, void *cookie)
> +{
> +  for (unsigned i = 0; i < v->length (); i++)
> +    op (&((*v)[i]), cookie);
> +}
> +
> template<typename T, typename A>
>   void
>   gt_pch_nx (vec<T *, A, vl_embed> *v, gt_pointer_operator op, void *cookie)
> @@ -1354,6 +1380,15 @@ gt_pch_nx (vec<T, A, vl_embed> *v, gt_pointer_operator op, void *cookie)
>       gt_pch_nx (&((*v)[i]), op, cookie);
>   }
>   
> +template<typename T>
> +void
> +gt_pch_nx (vec<T> *v, gt_pointer_operator op, void *cookie)
> +{
> +  extern void gt_pch_nx (T *, gt_pointer_operator, void *);
> +  for (unsigned i = 0; i < v->length (); i++)
> +    gt_pch_nx (&((*v)[i]), op, cookie);
> +}
> +
>
> After that, I get linking errors because the linker can not find
> gt_ggc_mx (tree *&x) nor void gt_pch_nx (tree *&x). The thing
> is: it doesn't matter where I implement them, or if I declare
> them inline. I always get a linking error one way or another.
>
> Therefore, what should I do to correctly implement the support
> for vec<tree*> types?
>
> Thank you,
> Giuliano.
>
Giuliano,
If your talking about gcc/vec.h there seems to be versions of them 
defined starting
on line 1304 of the mainline tree after grepping the source code. Not 
sure if the
linker is complaining about that as I don't have your errors.

Maybe that helps you out,

Nick