On Fri, Aug 17, 2012 at 7:05 PM, Richard Earnshaw <rearn...@arm.com> wrote: > On 17/08/12 16:20, Richard Earnshaw wrote: >> Ok, in which case we have to give is_widening_mult_rhs_p enough smarts >> to not strip >> >> (s32)u32 >> >> and return u32. >> >> I'll have another think about it. > > Take two. > > This version should address your concerns about handling > > (u32)u16 * (u32)u16 -> u64 > > We now look at each operand directly, but when doing so we check whether > the operand is the same size as the result or not. When it is, we can > strip any conversion; when it isn't the conversion must preserve > signedness of the inner operand and mustn't be a narrowing conversion. > > * tree-ssa-math-opts.c (widening_mult_conversion_strippable_p): > New function. > (is_widening_mult_rhs_p): Use it. > > Testing underway (again) > > OK?
Ok. Thanks, Richard. > R. >
