Re: [PATCH v4 5/5] perf metric: Don't compute unused events.

Andi Kleen
2020-12-02T06:39:10Z

> +| expr '-' expr
> +{
> + if (!compute_ids || (is_const($1.val) && is_const($3.val))) {
> + assert($1.ids == NULL);
> + assert($3.ids == NULL);
> + $$.val = $1.val - $3.val;
> + $$.ids = NULL;
> + } else {
> + /* LHS and/or RHS need computing from event IDs so union. */
> + $$ = union_expr($1, $3);
> + }

Can't this be all in a macro? It's still a lot of duplication.

I'm still not a fan, but I think with a macro it wouldn't be too bad.

-Andi