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


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