Re: [PATCH v2] powerpc: add setmaskedbits macros

On Thu, 16 Aug 2007, Michael Ellerman wrote:

Can you extract the masking logic, rather than repeating it 7 times:

#define maskbits(a, v, m)	((a) & ~(m) | (v))

And if you're going to the trouble of making a macro, why not make it a
bit more useful and have it check that the value and the mask match, ie:

(v & ~m == 0)

Final random thought, you could make the size/endian an argument:

#define setmaskedbits(a, v, m, s)  out_##s((a), (in_##s(a) & ~(m) | (v))

For readability, you can change the parameter names `v' and `m' to e.g. `set'
and `clear' (or `clr'), so people don't have to look through the actual
definitions to know which one comes first?

With kind regards,
 
Geert Uytterhoeven
Software Architect

Sony Network and Software Technology Center Europe
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