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Re: Make condition variables take absolute wakeup time
In article <200805071605.MAA14765%Sparkle.Rodents.Montreal.QC.CA@localhost> der
wrote:
: > These days, does hz >> 2 ever generate better code than hz / 4?
: <kernel.h> says hz is signed, so, if shifts are faster than divides, I
: would expect >>2 to be faster than /4. If the hardware doesn't have a
: signed-integer divide but does have shifts (eg, least common
: denominator sparc32), >>2 should be smaller than /4 too.
Actually, I would expect modern compilers to know that and convert
/4 into >>2 internally, when advantageous. IIUC, we are talking about
constants here.
yours,
dillo
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