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A library and stand alone assembler for aeternity bytecode.

This version supports AEVM bytecode and FATE bytecode.


$ make

Fate Code

Fate code exists in 3 formats:

  1. Fate byte code. This format is under consensus.
  2. Fate assembler. This is a text represenation of fate code. This is not under consensus and other implemenation and toolchains could have their own format.
  3. Internal. This is an Erlang representation of fate code Used by this particular engin implementation.

This library handles all three representations. The byte code format is described in a separate document. The internal format is described in a separate document. The text representation is described below.

Fate Assembler Code

Assembler code can be read from a file. The assembler has the following format:

Comments start with 2 semicolons and runs till end of line ;; This is a comment

Opcode mnemonics start with an upper case letter. DUP

Identifiers start with a lower case letter an_identifier

References to function arguments start with arg followed by an integer arg0

References to variables/registers start with var followed by an integer var0

References to stack postions is either a (for stack 0) or start with stack followed by an integer stack1 a

Immediate values can be of 10 types:

  1. Integers as decimals: {Digits} or -{Digits} 42 -2374683271468723648732648736498712634876147 And integers as Hexadecimals:: 0x{Hexdigits} 0x0deadbeef0

  2. Chain Objects. These are all addresses to different types of chain objects. Each address is a 256 bits number encoded in base58 with checksum with a prefix of "@" plus a type prefix followed by "_".

2a. Account Address: a base58c encoded number starting with @ak_ followed by a number of base58chars '@ak_nv5B93FPzRHrGNmMdTDfGdd5xGZvep3MVSpJqzcQmMp59bBCv`

2b. Contract address: @ct_{base58char}+ @ct_nv5B93FPzRHrGNmMdTDfGdd5xGZvep3MVSpJqzcQmMp59bBCv

2c. Oracle address: @ok_{base58char}+ @ok_nv5B93FPzRHrGNmMdTDfGdd5xGZvep3MVSpJqzcQmMp59bBCv

2d. Oracle query: @oq_{base58char}+ @oq_nv5B93FPzRHrGNmMdTDfGdd5xGZvep3MVSpJqzcQmMp59bBCv

2e. Channel address: @ch_{base58char}+ @ch_nv5B93FPzRHrGNmMdTDfGdd5xGZvep3MVSpJqzcQmMp59bBCv

  1. Boolean true or false true false

  2. Strings "{Characters}" "Hello"

  3. Map { Key => Value } {} { 1 => { "foo" => true, "bar" => false}

  4. Lists [ Elements ] [] [1, 2]

  5. Bit field < Bits > or !< Bits > <000> <1010 1010> <> !<>

  6. Tuples ( Elements ) () (1, "foo")

  7. Variants: (| [Arities] | Tag | ( Elements ) |) (| [1,3,5,2] | 3 | ( "foo", 12) |)

  8. Bytes: #{base64char}+ #AQIDCioLFQ==

  9. Contract bytearray (code of another smart contract) @cb_+PJGA6A4Fz4T2LHV5knITCldR3rqO7HrXO2zhOAR9JWNbhf8Q8C4xbhx/gx8JckANwAXfQBVACAAAP4vhlvZADcABwECgv5E1kQfADcBBzcACwAWMBReAHMAFjBvJFMAFjBvggOoFAAUABQSggABAz/+tIwWhAA3AAdTAAD+1jB5kAQ3AAcLAAD+6MRetgA3AQc3ABoGggABAz+4TS8GEQx8JclFY2FsbGVyX2lzX2NyZWF0b3IRL4Zb2Q1nZXQRRNZEHxFpbml0EbSMFoQdYmFsYW5jZRHWMHmQFXZhbHVlEejEXrYNc2V0gi8AhTQuMy4wAUqQ8s4=


Digits: [0123456789]

Hexdigits: [0123456789abcdef]

base58char: [123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]

base64char: [ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxy0123456789+/=]

Characters: any printable ascii character 0..255 (except " no quoting yet)

Key: any value except for a map

Bits: 01 or space

Elements: Nothing or Value , Elements

Size: Digits (0 < Size < 256)

Tag: Digits (0 =< Tag < Size)