Messages in this thread | | | Date | Thu, 10 Dec 2009 09:55:51 -0800 | From | David Daney <> | Subject | Re: [PATCH] ARM: Convert BUG() to use unreachable() |
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Russell King - ARM Linux wrote: > On Tue, Dec 08, 2009 at 10:55:38AM +0100, Uwe Kleine-König wrote: >> Use the new unreachable() macro instead of for(;;); > > Have you investigated what effect this has on generated code?
Yes.
Pre GCC-4.5 the generated code should be identical as 'unreachable()' just expands to 'for(;;);' in this case.
Post GCC-4.5 the generated code should be smaller.
I have not tested on ARM, but on x86_64, i686, and mips64 this is the case. The code size reduction is due to not emitting an endless loop after the asm() that never returns.
David Daney -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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