-O0 implies -o=0 -r=0 -so=0
-O1 implies -o=1 -r=0 -so=2
-O2 implies -o=5 -r=0 -so=3
-O3 implies -o=5 -r=2 -so=3
-sopt implies -o=5 -r=0 -so=3
-mp implies -o=0 -r=0 -so=0 and recognize parallel directives
-pfa implies -o=5 -r=0 -so=3 (plus automatic parallelization)
For combinations of either -On -pfa or -On -sopt, the greater of the implied options is taken. For example, with -O1 -sopt, the resulting set of KAP options is -o=5 -r=1 -so=3.