/usr/lib/mlton/sml/mlrisc-lib/instructions/ is in mlton-basis 20130715-3.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/mlton/sml/mlrisc-lib/instructions/block-names.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/cells-basis.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/cells-basis.sml
/usr/lib/mlton/sml/mlrisc-lib/instructions/cells.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/cells.sml
/usr/lib/mlton/sml/mlrisc-lib/instructions/constant.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/expandCopies.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/freqProps.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/freqProps.sml
/usr/lib/mlton/sml/mlrisc-lib/instructions/insnProps.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/instructions.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/label-sig.sml
/usr/lib/mlton/sml/mlrisc-lib/instructions/label.sml
/usr/lib/mlton/sml/mlrisc-lib/instructions/mlriscAnnotations.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/mlriscAnnotations.sml
/usr/lib/mlton/sml/mlrisc-lib/instructions/mlriscOptimization.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/peephole.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/pseudoOps.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/region.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/regionInfo.sml
/usr/lib/mlton/sml/mlrisc-lib/instructions/regionProps.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/rewrite.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/shuffle.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/shuffle.sml
/usr/lib/mlton/sml/mlrisc-lib/instructions/stream.sig
/usr/lib/mlton/sml/mlrisc-lib/instructions/stream.sml