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Date: Thu, 11 Oct 2007 14:55:44 -0500
From: Scott Wood <scottwood@freescale.com>
To: Olof Johansson <olof@lixom.net>
Subject: Re: [PATCH 2/2] powerpc: Switch to generic WARN_ON()/BUG_ON()
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On Thu, Oct 11, 2007 at 12:14:13PM -0500, Olof Johansson wrote:
> 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'd be nice if we could get GCC to generate bug table entries for
__builtin_trap(); that way we could use GCC's ability to put arbitrary
conditions in the trap instruction.

-Scott

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Date: Thu, 11 Oct 2007 14:55:44 -0500
From: Scott Wood <scottwood@freescale.com>
To: Olof Johansson <olof@lixom.net>
Cc: linux-kernel@vger.kernel.org, grundler@parisc-linux.org,
       kyle@parisc-linux.org, linuxppc-dev@ozlabs.org, lethal@linux-sh.org,
       akpm@linux-foundation.org
Subject: Re: [PATCH 2/2] powerpc: Switch to generic WARN_ON()/BUG_ON()
Message-ID: <20071011195544.GA4247@loki.buserror.net>
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On Thu, Oct 11, 2007 at 12:14:13PM -0500, Olof Johansson wrote:
> 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'd be nice if we could get GCC to generate bug table entries for
__builtin_trap(); that way we could use GCC's ability to put arbitrary
conditions in the trap instruction.

-Scott