[Comb] Fold comb.truth_table when truth table depends on a single operand #8925
Description
hw.module @Foo(in %c : i3, out out : i1) {
%0 = comb.extract %c from 2 : (i3) -> i1
%1 = comb.extract %c from 1 : (i3) -> i1
%2 = comb.extract %c from 0 : (i3) -> i1
%3 = comb.truth_table %2, %0, %1 -> [false, false, false, false, true, true, true, true]
hw.output %3 : i1
}
%3 should be canonicalized to %2 as the truth table depends on a single variable:
00001111
00110011
01010101