systimer01.patch available for review.

Joerg Sonnenberger joerg at britannica.bec.de
Thu Jan 29 06:13:09 PST 2004


On Thu, Jan 29, 2004 at 01:50:21PM -0600, Dave Leimbach wrote:
> How is it that a function written in assembly will create performance issues
> over one written in C that uses inline assembly?  Is it some human factor?

The compiler can't optimize it e.g. via inling the call. Consider the
example of inb/outb which needs one instruction. if this are written
as separate function, you need a call/ret pair, instructions to save and
read the arguments etc. therefore this is way slower.

Joerg

> 
> 
> Dave
> 





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