EEVM

EEVM is an EVM implementation for Erlang Virtual Machine. It is developed by ThePower project for embedding into ThePower blockchain, but it is perfectly isolated from ThePower node code and can be easily embedded in any Erlang application.

EEVM runs Solidity code compiled by solc without any modifications.

This implementation only requires KECCAK-256 library as dependence. It uses KSHA3 by default, but there is also slow, but pure-erlang ESHA3 implemantation used by various utilities. This pure-erlang implementation can be escriptized (packed into one escript-runnable file).

Interpreter

The Erlang VM interpreter is used.

Prerequisites

Erlang version
22 or upper

Usage

How to build EEVM?

To build EEVM, run:

./rebar3 compile

How to run EEVM?

Use the following command, to run EEVM:

./rebar3 shell

After you run the command, you'll get into the Erlang shell. This shell allows you to run tests from eevm_scratchpad.erl. You can look through the code and play with it. In the example below, you'll play with eevm_scratchpad:tether().

After running the test, you will get something like this:

> eevm_scratchpad:tether().
St1 #{0 => 49374,1 => 131072,3 => 0,4 => 0,7 => 0,8 => 0,9 => 3,10 => 0,
      67310910001236471336487740600394280602614355732742098307022882807426235821668 =>
          131072}
Bals 131072/0/0
LOG: <<0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,100>>
        args [63486140976153616755203102783360879283472101686154884697241723088393386309925,
              49374,256]
Res stop
Bals 131072/0/0
LOG: <<0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,94>>
        args [100389287136786176327247604509743168900146139575972864366142685224231313322991,
              49374,512]
Res stop
Bals 130978/0/94
LOG: <<0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,5>>
        args [100389287136786176327247604509743168900146139575972864366142685224231313322991,
              49374,256]
Res stop
Bals 130973/5/94
#{0 => 49374,1 => 131072,3 => 0,4 => 0,7 => 0,8 => 0,9 => 3,
  10 => 0,
  47308557215275847810576800605663265607653752947282041372765295433751199017549 =>
      5,
  67310910001236471336487740600394280602614355732742098307022882807426235821668 =>
      130973,
  75831452412138323880916444173573612722054346159677297449878335876480453112616 =>
      94,
  109967025685673354741881731518503272060083192313621507584907820637209627593305 =>
      1}

where

Field	Description
St1	A storage, where the smart contract is stored
Bals	Returns the value of balanceOf call for three addresses used in the example test
LOG	Contains data sent to EVM interpreter by the smart-contract

Also, you can see the final state after 3 transactions are finished.

TO-DO

• Add self-destruction opcode.
• Add EVM tests.
• Check gas calculation.