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Re: -fnon-call-exceptions + -fprofile-arcs on x86

From: Eric Botcazou <ebotcazou at act-europe dot fr>
To: Nathan Sidwell <nathan at codesourcery dot com>
Cc: gcc at gcc dot gnu dot org
Date: Mon, 10 May 2004 20:08:44 +0200
Subject: Re: -fnon-call-exceptions + -fprofile-arcs on x86
References: <200405101350.02551.ebotcazou@act-europe.fr> <409FA77E.1000406@codesourcery.com>

>   I don't see how, one of the two edges must be counted.  The exceptional
> edge cannot be, because there's no actual flow there.  So profile must
> add the incrementing code on the fall through edge.

That was my opinion too.

> I guess what needs to happen is that (when -fprofile-arcs is on) cc0 is
> clobbered at the end of every block.

RTH's fix aims to prevent the middle-end from generating compare insns that 
may trap if flag_non_call_exceptions is enabled.  I think that's the best we 
can do.

Thanks for your feedback.

-- 
Eric Botcazou

References:
- -fnon-call-exceptions + -fprofile-arcs on x86
  - From: Eric Botcazou
- Re: -fnon-call-exceptions + -fprofile-arcs on x86
  - From: Nathan Sidwell

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