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Date: Fri, 12 Oct 2007 11:23:39 +1000
From: Paul Mackerras <paulus@samba.org>
To: Olof Johansson <olof@lixom.net>
Subject: Re: [PATCH 2/2] powerpc: Switch to generic WARN_ON()/BUG_ON()
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Olof Johansson writes:

> Not using the ppc-specific WARN_ON/BUG_ON constructs actually saves about
> 4K text on a ppc64_defconfig. The main reason seems to be that prepping
> the arguments to the conditional trap instructions is more work than
> just doing a compare and branch.

It might be more instructions but it takes fewer cycles, I would
expect.  Do you have the actual instruction sequences to compare?

Paul.