Re: [PATCH v2] Avoid address_space_rw() with a constant is_write argument

[Eric Blake]

On 2/18/20 6:56 AM, Philippe Mathieu-Daudé wrote:

> > +++ b/scripts/coccinelle/as_rw_const.cocci
> > @@ -0,0 +1,30 @@
> > +// Avoid uses of address_space_rw() with a constant is_write argument.
> > +// Usage:
> > +//  spatch --sp-file as-rw-const.spatch --dir . --in-place
>
> Nitpick, script is now scripts/coccinelle/as_rw_const.cocci.
>
> Reviewed-by: Philippe Mathieu-Daudé <address@hidden>
>
> > +
> > +@@
> > +expression E1, E2, E3, E4, E5;
> > +symbol false;
> > +@@
> > +
> > +- address_space_rw(E1, E2, E3, E4, E5, false)
> > ++ address_space_read(E1, E2, E3, E4, E5)
> > +@@
> > +expression E1, E2, E3, E4, E5;
> > +@@
> > +
> > +- address_space_rw(E1, E2, E3, E4, E5, 0)
> > ++ address_space_read(E1, E2, E3, E4, E5)

This feels a bit redundant.  Doesn't coccinelle have enough smarts about 
isomorphisms (such as 0 == false, 1 == true) that it could get by with 
one @@ hunk instead of 2, if we come up with the right way to represent 
any isomorphism to a constant value?  But admittedly, I don't know what 
that representation would actually be, and your verbose patch works even 
if it is not the most concise possible.  So don't let my remarks hold 
this patch up.

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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