On 04/27/2010 08:41 PM, Jonas Paulsson wrote: >> I've recently been bitten by the lost-widening-multiplication- >> when-in-loop issue myself, and noted it for revisit Some Day. >> Fixing that by other means made a whopping 27% improvement for >> the application where I saw it: a hot loop doing a MDCT using >> Q31 fixed-point, where a common operation is to widen-multiply >> two 32-bit numbers and pick the high 32 bits of the 64-bit >> result (being the result divided by 2; i.e. Q30-ish for that >> operation). >> >> brgds, H-P
Widening multiplies should work again after r158633 and 158643. If there are cases that still don't work for you, please file bugzilla PRs. Bernd
