Meow is an esoteric language created for fun purposes and this repo contains bytecode interpreter for meow.

mkdir bin
make

meow input.meow

Every meow instruction is 8-bit, first 3 bit represents operation type, last 5 represents operation itself.

Meow instructions are encoded into two parts firstly #m + #e - 2 gives us info about type of instruction there are 4 types at total:

• V-Type (Operations to manipulate variables)
• A-Type (Arithmetic operations)
• C-Type (Control flow operations)
• S-Type (Operations that makes syscalls like printf)

We use #o + #w - 2 to get information about second part of instruction.
this part specifies which instruction we want ie:

• meow is decoded to 00000000 which is equilevant of LOAD_CONST in bytecode.
• meoow is decoded to 00000001 which is equilevant of LOAD_VAR in bytecode.
• meeow is decoded to 00100000 which is equilevant of ADD in bytecode.
• mmeeoooww is decoded to 01000101 which is equilevant of JGE in bytecode. it is worthy to remind meoow and meoww generates same instruction.

You can find more information about instruction encodings at src/lut.c.

Here is an example to find nth fibonacci number in meow.

nyan main:
    meow 4
    meooww ~~n

    meow 0
    meow 1
    meow 0

    meooww ~~a
    meooww ~~b
    meooww ~~tmp

    meoww ~~n
    meow 0
    mmeeow
    mmeeooww base

    meow 2
    meooww ~~it_count

nyan fib_rec:
    meoow ~~a
    meoow ~~b
    meeow
    meooww ~~tmp

    meoww ~~b
    meooww ~~a
    meoow ~~tmp
    meooww ~~b

    meoow ~~it_count
    meow 1
    mmeow
    meooww ~~it_count
    meoow ~~it_count
    meoow ~~n
    mmeeow
    meeeooowwwwww fib_rec
    mmeeoow fin

nyan base:
    meow 0
    meeeeow
    meeeeoww

nyan fin:
    meoww ~~n
    meow ". Fibonacci number is "
    meeow
    meoww ~~b
    meeow
    meeeeow