Jean Delvare wrote:
Hi Bill,
On Fri, 30 Nov 2007 07:04:10 -0600, Bill Gatliff wrote:
Jean Delvare wrote:
!!(value & (1 << offset))
is more efficiently written
(value >> offset) & 1
... but not more efficiently implemented.
Your version requires code to do the shift on live data at runtime.
David's version lets the compiler create the mask once, at compile-time.
I don't understand. How could the compiler create the mask at
compile-time when "offset" is only known at runtime?
Oops. :) I was thinking of some different code. Disregard.
/me got up too early this morning, after working too late last night!
b.g.
--
Bill Gatliff
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