[match-and-simplify] support operator list

[Richard Biener]

On Mon, Nov 3, 2014 at 1:56 PM, Prathamesh Kulkarni
<bilbotheelffriend@gmail.com> wrote:
> (had sent it earlier by private mail).
>
> The attached patch supports operator-list and it's use in for.
> For now, operator-list is rejected in expression.

Ok.

> This patch also allows user-defined operator to be used as operator-list
> (user-defined ops are really temporary or "scoped" operator-lists).
> (for op (plus minus)
>       op2 (op...)
>   (simplify
>      ...))
>
> Should that be supported or rejected ?

I've made it supported, but not in the way you implemented it.  Instead
I am only expanding operator lists.  Thus

(for op (plus minus)
 (for op2 (minus op)
  ...

will iterate (op, op2) (plus, minus) (minus, minus) (plus, plus) (minus, minus).

I think that makes more sense(?) but it's maybe too confusing as well so
eventually we should reject this.

I've adapted the patch slightly, using safe_splice, adding a comment and
avoiding a long line.

I've also used an example operator list in match-builtin.pd instead where
it shows the obvious improvement we're going to implement.

Committed.

Thanks,
Richard.

2014-11-04  Prathamesh Kulkarni  <bilbotheelffriend@gmail.com>

        * genmatch.c (user_id): Add new member is_oper_list.
        (user_id::user_id): Add new default argument.
        (parser::parse_operator_list): New function.
        (parser::parse_for): Allow operator-list.
        (parser::parse_pattern): Call parser::parse_operator_list.
        (parser::parse_operation): Reject operator-list.
        * match-builtin.pd: Define operator lists POWs, CBRTs and SQRTs.

(gmail is too stupid to attach stuff it seems)

> * genmatch.c
>   (user_id): Add new member is_oper_list.
>   (user_id::user_id): Add new default argument.
>   (parser::parse_operator_list): New function.
>   (parser::parse_for): Allow operator-list.
>   (parser::parse_pattern): Call parser::parse_operator_list.
>   (parser::parse_operation): Reject operator-list.
>
> * match-comparison.pd
>   Define operator-lists eq_ops and cc and use them in patterns.
>
> Thanks,
> Prathamesh