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Re: CVS commit: src/sys/dev/ic



On Sat, Feb 27, 2010 at 04:40:12AM +0000, Izumi Tsutsui wrote:
> 
> Log Message:
> Always call device dependent functions via pointers rather than
> using conditionals to switch inline functions for modern processors.

Eh ???
    if (foo) bar(); else baz();
will probably execute faster than:
    (*bar_baz)();
since the indirect jump is (IIRC) always unpredicted.
the 'if' version stands a chance of correctly predicting the jump.

        David

-- 
David Laight: david%l8s.co.uk@localhost


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