http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50281 --- Comment #7 from NickParker at Eaton dot com 2011-09-03 04:45:08 UTC --- Please ignore the r10/r20 guff I was experimenting. I later realised the muls3s3u3 code gives the right answer, the problem occurs later on somehow Nick.