On Mon, Jun 21, 2010 at 5:25 PM, Bernd Schmidt <ber...@codesourcery.com> wrote:
> In PR43902, Jim has posted a patch to add support for widening
> multiply-accumulate to tree-ssa-math-opts. They are represented as a
> GIMPLE_SINGLE_RHS with a WIDEN_MULT_PLUS_EXPR tree which holds the
> actual operands of the multiply-accumulate. I've modified this a bit so
> that we now support gimple statements with a GIMPLE_TERNARY_RHS class
> (see the other patch I've added to the PR), but while testing I found
> that we already create DOT_PROD_EXPRs, which are also three-operand
> expressions, with the same GIMPLE_SINGLE_RHS representation used by
> Jim's patch.
>
> What's actually intended here? Should we add real support for
> three-operand gimple statements and change the code that generates
> DOT_PROD_EXPR, or should we add WIDEN_MULT_{PLUS,MINUS}_EXPR in the same
> way DOT_PROD_EXPR is handled at the moment?
We should add support for a GIMPLE_TERNARY_RHS class.
Richard.
>
> Bernd
>
>
