Matteo Bruni (@Mystral) commented about dlls/d3dx9_36/preshader.c:
{ if (arg->index_reg.table == PRES_REGTAB_COUNT) {
TRACE("%s%u.", table_symbol[table], get_reg_offset(table, arg->reg.offset));
TRACE("%s%u.", table_info[table].symbol, get_reg_offset(table, arg->reg.offset)); }
I guess we might as well hardcode the "(null)" here and avoid the additional entry in the table. Mostly because otherwise the extra entry kind of suggests that the table is scanned until the "terminator", which is not the case.
Not a big deal, I don't really mind either way.