The update for London (EIP-1559) in 1cdb30df ("bump nim-emvc with evmc revision
8.0.0 to 9.0.0") really bumped EVMC ABI version from 7.5 up to 9.
In other words, it skipped Berlin, going direct from Istanbul to London.
That was accompanied by EVMC changes in 05e9b891 ("EIP-3198: add baseFee op
code in nim-evm"), which added the API changes needed for London.
But the missing Berlin functions weren't added in the move to London.
As a result, our EVMC host became incompatible with Berlin, London, and really
all revisions of the ABI, and if a third party EVM was loaded, it crashed.
This commit adds the missing Berlin host support, and makes our ABI
binary-compatible with real EVMC again.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
1. Send all EVM executions through the EVMC `execute` function.
It leads to the same place in the end as calling `Computation` before, but
`execute` is the API function used by all EVMC implementations, and it is
very explicit what data is passed back and forth.
2. As a consequence this starts using the new `host_services` code from EVM, so
this is a significant change to the paths used for account state processing.
3. Because we will have to remove the `newComputation` call on the host side,
anticipating that the contract code is now saved in `host` instead of being
copied around. As it's saved in `host`, there is no need to pass it
separately to `evmcExecComputation`.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
`TransactionHost` represents the interface to the EVM from the application once
we've fully transitioned to EVMC. It represents a managed EVM call, and the
"EVMC host" side of the host<->EVM boundary.
This holds transaction state which sits outside the EVM, but a pointer to this
is passed around by the EVM as _opaque_ type `evmc_host_context`.
To the EVM, this offers "host services", which manage account state that the
EVM cannot do, such as balance transfers, call costs, storage, logs, gas
refunds, nested calls and new contract addresses. The EVM has no direct access
to the account state database or network; it's all via "host services".
To the application (host side), this object represents a managed EVM call, with
inputs, a method to run, outputs, hidden transaction state, and later async
scheduling. It is to replace `Computation` on the application side, while
`Computation` will remain but just be for the EVM side.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
Jamie Lokier