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Re: Example of C and inline ASM in a file?

2006-04-09 by Stephen Pelc

> Robert Adsett <subscriptions@...> 

> Indeed, I've yet to see a good reason to use inline
> assembler on any processor and that's doubly true for the
> ARM. 

When you need efficient access to ideas not supported by the 
programming language. These are usually things like the state of 
the Carry and Overflow flags. Using assembler rather than high 
level kluges can improve performance by factors of 2..5, 
depending on CPU.

A client of ours performs financial calculations using 128 bit 
integers. The difference between their app and the competition's 
floating point app for part of the Hong Kong airport 
construction was US dollars 10,000,000. The on-screen 
recalculation performance was important, so they coded the quad-
integer routines.

Stephen
--
Stephen Pelc, stephen@...
MicroProcessor Engineering Ltd - More Real, Less Time
133 Hill Lane, Southampton SO15 5AF, England
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