On Sat, Jun 12, 2021 at 5:21 PM Andrew Pinski <pins...@gmail.com> wrote: > > 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.
I figured out why; lower_cond does not copy for_subst_vec for the new simplifier. Fixing that allows the switching of the order of the two lower functions which is needed in this case. I will submit the patch for this when I submit the patch set for converting the simple "A CMP 0 ? A : - A" of fold_cond_expr_with_comparison. Thanks, Andrew Pinski > > Thanks, > Andrew > > > > > Thanks, > > Andrew Pinski
