Required option 'instruction' missing
Usage: isla-footprint [options]

Options:
    -T, --threads <n>   use this many worker threads
    -A, --arch <file>   load architecture file
    -C, --config <file> load custom config for architecture
        --toolchain <name>
                        use specified toolchain from config
    -R, --register <register>=<value>
                        set a register, via the reset_registers builtin
    -I, --initial <register>=<value>
                        set a register in the initial state
    -h, --help          print this help message
        --verbose       print verbose output
    -D, --debug <flags> set debugging flags
        --probe <id>    trace specified function calls or location assignments
                        in debug output
        --probe-all     probe everything (very verbose)
        --probe-function <id>
                        probe everything under the specified function (very
                        verbose)
        --trace-function <id>
                        trace specified function calls in the trace output
        --trace-all     trace everything
    -L, --linearize <id>
                        rewrite function into linear form
    -P, --partial-linearize <id>
                        rewrite function into linear form
    -S, --source <path> directory containing the Sail source used to generate
                        the IR
        --test-linearize
                        test that linearization rewrite has been performed
                        correctly
        --abstract <id> make function abstract
        --debug-id <name id>
                        print the name of an interned identifier (for
                        debugging)
        --reset-constraint <constraint>
                        property to enforce at the reset_registers builtin
        --fork-assertions
                        change assertions into explicit control flow
        --fun-assumption <assumption>
                        add an assumption about the behaviour of a Sail
                        function
        --no-model-reg-init
                        don't use register initializers from the model
        --version       print out version and stop.
    -i, --instruction <instruction>
                        display footprint of instruction
    -e, --endianness big/little
                        instruction encoding endianness (default: little)
        --elf <file>    load an elf file, and use instructions from it
    -d, --dependency    view instruction dependency info
    -x, --hex           parse instruction as hexadecimal opcode, rather than
                        assembly
    -s, --simplify      simplify instruction footprint
        --simplify-registers
                        simplify register accesses in traces
        --hide          hide uninteresting trace elements
    -t, --tree          combine traces into tree
    -f, --function <identifer>
                        use a custom footprint function
    -c, --continue-on-error
                        continue generating traces upon encountering an error
        --armv8-page-tables <constraints>
                        set up page tables with provided constraints
        --zero-memory   treat all memory as being zero
        --partial       parse instruction as binary with unknown bits
        --from-file <file>
                        parse instruction from opcodes file
        --instruction-constraint <constraint>
                        add constraint on variables in a partial instruction
        --eval-carefully
                        during simplification check the results of symbolic
                        evaluation
    -k, --kill-at <function name[, function_name]>
                        stop executions early and discard if they reach this
                        function (with optional context)
        --stop-at <function name[, function_name]>
                        stop executions early and keep trace if they reach
                        this function (with optional context)
        --pessimistic   fail on any assertion that is not necessarily true
        --timeout <n>   Add a timeout (in seconds)
        --executable    make trace executable