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

[Horst von Brand]

Marcin Dalecki <martin@xxxxxxxxxx> said:
> On 2005-03-27, at 00:21, linux-os wrote:
> > Always, always, a call will be more expensive than a branch
> > on condition.

Wrong.

> >               It's impossible to be otherwise.

Many, many counterexamples say otherwise...

> >                                                A call requires
> > that the return address be written to memory (the stack),

Not necesarily right now, it can be done at leisure later on while doing
other stuff.

> > using register indirection (the stack-pointer).

So what? The stack pointer is surely special. Modern programming languages
(and programming styles) encourage many calls, so this is very heavily
optimized.

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

The mechanism exists somehow.
-- 
Dr. Horst H. von Brand                   User #22616 counter.li.org
Departamento de Informatica                     Fono: +56 32 654431
Universidad Tecnica Federico Santa Maria              +56 32 654239
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