[Re: new plugin events]

[Terrence Miller]

< Forwarded due to missing address>

-------- Original Message --------
Subject: 	Re: new plugin events
Date: 	Sun, 08 Nov 2009 18:25:21 +0100
From: 	Basile STARYNKEVITCH <basile@starynkevitch.net>
To: 	Terrence Miller <terrencem@sbcglobal.net>
References: 	<4AE72A4F.8000303@starynkevitch.net> 
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<38a0d8450911050824l838fd92ya9f3a08205c80a85@mail.gmail.com> 
<4AF33453.7090200@starynkevitch.net> 
<38a0d8450911060724h3c6f9ddh3e84c2c763ac4de0@mail.gmail.com> 
<b798aad50911060800w5bffaf50tdabbbf2d78be4d22@mail.gmail.com> 
<84fc9c000911060818s3462aff1r1ebfb298506b6939@mail.gmail.com> 
<b798aad50911060827r1105ad3fna194ff5b898ce95@mail.gmail.com> 
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<b798aad50911061036g3be83df2n8d8ca5c4144c3c8d@mail.gmail.com> 
<4AF47257.8040307@starynkevitch.net> <4AF6FB88.4030303@sbcglobal.net>



Terrence Miller wrote:
> I think this debate is missing one important issue. In order to generate 
> a patch to GCC
> you have to know a lot more about the compiler internals than is 
> required to create
> a plugin.  I am doing some casual experimentation with compiler based 
> source browsing
> and would love to have the DECL event(described below) added to the 
> plugin API.
> I would prefer to not have to figure where that plugin should be called.
> 

It is perhaps true for the DECL event you are talking about (which I did not understood fully), but I won't say that 
coding a plugin is *in general* easier than proposing a patch to core GCC.

My perception is that most *middle* end plugins are working on Gimple and other middle-end representations. Usually, 
they do that by adding a pass in the pass machinery. And knowing what pass to add (or replace) is as difficult when 
coding a plugin than when coding a patch to GCC core.

Conversely, I would suspect than many previous patches (which have now bee incorporated in GCC core) could have if a 
plugin machinery have been available at their time (which is false since plugin facilities is just coming in 4.5 which 
has not yet been released), first been developped as plugins -at least to experiment their viability & interest- and 
later one proposed as a patch.

This is why I believe that plugins will probably -at least for middle-end processing- have also the role of GCC branches 
today, with a very important difference. Almost nobody compiles branches today (in the general GCC user community - I am 
not talking of the smaller GCC developper community), and it could be the case that some plugins will be used.

For example, as far as I know, no common Linux distribution provides a package for any kind of GCC branch. I believe 
(perhaps I am too optimistic) that some Linux distributions will package some few GCC plugins.

Apparently you did not sent your reply to gcc@; feel free to forward this (or any reply to gcc@ if you want).

Regards.

-- 
Basile STARYNKEVITCH         http://starynkevitch.net/Basile/
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