[Bug target/50256] AVR GCC - several unnecessary register moves

[NickParker at Eaton dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50256

--- Comment #4 from NickParker at Eaton dot com 2011-09-04 21:27:43 UTC ---
Hi,

Thanks for your input and sorry to make a mess of reporting this.
The arithmetic is fine and the code gives the results I expect.
However, I have since discovered and corrected a 'bug'.  
I was not initialising my 'temporary result registers i.e. r2,r3,r4,r5,r6,r7.

Regarding the arithmetic, the result is INTENTIONALLY accumulated from the
lowest partial products to highest partial products so that at most only 3
additions are ever needed per partial product.


Thanks, Nick