Re: [patch 2.6.20-rc1 4/6] PXA GPIO wrappers

[Bill Gatliff]

Guys:

> > Probably? What I am wondering is this: can the compiler
> > optimize away the range check that is duplicated in GPSR/GPCR
> > and  GPIO_bit for __gpio_set/get_value? Or could we optimize
> > this case by expanding the macros in place (which would mean
> > duplicating code from pxa-regs.h)...
> >    

Who cares?  :)

I don't think there's much point in optimizing here, since these 
functions won't be hot paths anyway.  Yes, they'll be called in 
interrupt handlers and so we don't want them to be _too_ heavy, but 
compared to the overhead of an interrupt handler, a few extra 
instructions in the GPIO access will get lost in the noise.

Inlines generally seem to be more maintainable, give you a symbol that 
you can disassemble and breakpoint, etc.  I'll take them over the macro 
implementations any day, in this case even if there's a cost of a few 
instructions.

All IMHO, of course.


b.g.

--
Bill Gatliff
bgat@xxxxxxxxxxxxxxx

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