On Sat, Jun 12, 2021 at 4:54 PM Andrew Pinski <pins...@gmail.com> wrote: > > Hi all, > While moving the simple A CMP 0 ? A : -A patterns from > fold_cond_expr_with_comparison to match, I ran into an issue where > using cond directly in the patterns work while "for cnd (cond > vec_cond)" don't work. > It looks like in the first case we are able to correctly handle the > cond first operand being a comparison while with the for loop we are > not. > > That is the following additional pattern works: > /* A == 0? A : -A same as -A */ > (simplify > (cond (eq @0 zerop) @0 (negate@1 @0)) > (if (!HONOR_SIGNED_ZEROS (element_mode (type))) > @1)) > (simplify > (cond (eq @0 zerop) zerop (negate@1 @0)) > (if (!HONOR_SIGNED_ZEROS (element_mode (type))) > @1))) > > While this one does not work: > (for cnd (cond vec_cond) > /* A == 0? A : -A same as -A */ > (simplify > (cnd (eq @0 zerop) @0 (negate@1 @0)) > (if (!HONOR_SIGNED_ZEROS (element_mode (type))) > @1)) > (simplify > (cnd (eq @0 zerop) zerop (negate@1 @0)) > (if (!HONOR_SIGNED_ZEROS (element_mode (type))) > @1))) > > ---- CUT --- > I will try to debug genmatch some but I wanted to get this email out > to record what will need to be fixed to continue the movement of > phiopt over to match.
So the problem is we lower for loops first and then cond. Though swapping the order in genmatch's lower function causes invalid C++ code to be generated :(. Still trying to figure out why though. Thanks, Andrew > > Thanks, > Andrew Pinski
