Is there any PoC on implementing mathematical operations using Stateful Precompiles in Custom Subnets?

[ashucoder9]

Let's suppose I want to create a universal calculator precompile that performs computation like Addition.

Can be extended with toolings to store in the stateDB and more.

I am working on launching something similar to a Counter program and stuck in the contract phase so it'd helpful in understanding working of the functions and their interactions with variable states.

[aaronbuchwald]

You can write any golang program you want inside of each precompile function including accessing the stateDB directly if you want to read/write the storage trie of your precompile as long as it is deterministic.

Here's the stateful precompile tutorial: https://docs.avax.network/subnets/hello-world-precompile-tutorial and the most recent pending PR that will update it to make development easier: https://github.com/ava-labs/avalanche-docs/pull/1418/files (pending release of a new repo).

Could you be more specific about what issues you are running into?

[ashucoder9]

I have pushed a precompile contract in the counter-pc branch here: https://github.com/ashucoder9/subnet-evm/tree/counter-pc

Currently, my goal is to create a counter precompile that returns the value or increments by X as specified (can be 1 also for general increment).

Given that I do not have much experience with GoLang, I might be wrong in implementing the code. Might need a little help on that. Feel free to propose/comment any improvements!

Apart from that, is the precompile disabled by default? If yes, where do we enable it? I remember running the HelloWorld tutorial without any modifications for E2E tests (I assumed it was working PoC) and failed a test for which the most likely reasoning is that it may be disabled.

[ashucoder9]

Even though this attempt is focused on a generalized understanding of the working of mathematical operations with stateful precompiles, it can lead to developing custom EVM extensions that were not implemented in the Ethereum Virtual Machine like this.

[ashucoder9]

@ceyonur can you please check why the Ginkgo tests are failing to run: https://github.com/ashucoder9/subnet-evm/tree/counter-precompile

[aaronbuchwald]

Hey @ashucoder9 , it looks like CI is not running at all on that repo. Workflows are disabled by default (parameter of GitHub, not related to Subnet-EVM), so you should check to make sure that they are enabled and running correctly.

[ashucoder9]

No worries, I figured the rest out and also updated the docs with new detail. Thanks to @ceyonur!