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

[Eric Blake <eblake@redhat.com>]

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 <philmd@redhat.com>
> 
>> +
>> +@@
>> +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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