Choose a .aml / .dat file (e.g. DSDT). iASL writes a .dsl in the work directory (exact name depends on the table).
Supply SSDTs (or other tables) so external control methods can be resolved; same order as
iasl -e … -d … on the command line.
After compile: dsdt.aml. After disassemble: generated .dsl (name comes from the table / input file).