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

[Andi Kleen]

> +| 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