Re: [PATCH] no need to check for NULL before calling kfree() -fs/ext2/

From: linux-os
Date: Sun Mar 27 2005 - 17:14:23 EST


On Sat, 26 Mar 2005, Marcin Dalecki wrote:


On 2005-03-27, at 00:21, linux-os wrote:

Always, always, a call will be more expensive than a branch
on condition. It's impossible to be otherwise. A call requires
that the return address be written to memory (the stack),
using register indirection (the stack-pointer).

Needless to say that there are enough architectures out there, which
don't even
have something like an explicit call as separate assembler
instruction...


Yes, they break the 'call' into seperate expensive operations like
loading the IP address that will exist after the call into a register
storing that in a dedicated register, used as a "stack", then
branching to the called procedure with another indirection, etc.



Cheers,
Dick Johnson
Penguin : Linux version 2.6.11 on an i686 machine (5537.79 BogoMips).
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