* Added basic async capabilities for vm2.
This is a whole new Git branch, not the same one as last time
(https://github.com/status-im/nimbus-eth1/pull/1250) - there wasn't
much worth salvaging. Main differences:
I didn't do the "each opcode has to specify an async handler" junk
that I put in last time. Instead, in oph_memory.nim you can see
sloadOp calling asyncChainTo and passing in an async operation.
That async operation is then run by the execCallOrCreate (or
asyncExecCallOrCreate) code in interpreter_dispatch.nim.
In the test code, the (previously existing) macro called "assembler"
now allows you to add a section called "initialStorage", specifying
fake data to be used by the EVM computation run by that test. (In
the long run we'll obviously want to write tests that for-real use
the JSON-RPC API to asynchronously fetch data; for now, this was
just an expedient way to write a basic unit test that exercises the
async-EVM code pathway.)
There's also a new macro called "concurrentAssemblers" that allows
you to write a test that runs multiple assemblers concurrently (and
then waits for them all to finish). There's one example test using
this, in test_op_memory_lazy.nim, though you can't actually see it
doing so unless you uncomment some echo statements in
async_operations.nim (in which case you can see the two concurrently
running EVM computations each printing out what they're doing, and
you'll see that they interleave).
A question: is it possible to make EVMC work asynchronously? (For
now, this code compiles and "make test" passes even if ENABLE_EVMC
is turned on, but it doesn't actually work asynchronously, it just
falls back on doing the usual synchronous EVMC thing. See
FIXME-asyncAndEvmc.)
* Moved the AsyncOperationFactory to the BaseVMState object.
* Made the AsyncOperationFactory into a table of fn pointers.
Also ditched the plain-data Vm2AsyncOperation type; it wasn't
really serving much purpose. Instead, the pendingAsyncOperation
field directly contains the Future.
* Removed the hasStorage idea.
It's not the right solution to the "how do we know whether we
still need to fetch the storage value or not?" problem. I
haven't implemented the right solution yet, but at least
we're better off not putting in a wrong one.
* Added/modified/removed some comments.
(Based on feedback on the PR.)
* Removed the waitFor from execCallOrCreate.
There was some back-and-forth in the PR regarding whether nested
waitFor calls are acceptable:
https://github.com/status-im/nimbus-eth1/pull/1260#discussion_r998587449
The eventual decision was to just change the waitFor to a doAssert
(since we probably won't want this extra functionality when running
synchronously anyway) to make sure that the Future is already
finished.
* Redesign of BaseVMState descriptor
why:
BaseVMState provides an environment for executing transactions. The
current descriptor also provides data that cannot generally be known
within the execution environment, e.g. the total gasUsed which is
available not before after all transactions have finished.
Also, the BaseVMState constructor has been replaced by a constructor
that does not need pre-initialised input of the account database.
also:
Previous constructor and some fields are provided with a deprecated
annotation (producing a lot of noise.)
* Replace legacy directives in production sources
* Replace legacy directives in unit test sources
* fix CI (missing premix update)
* Remove legacy directives
* chase CI problem
* rebased
* Re-introduce 'AccountsCache' constructor optimisation for 'BaseVmState' re-initialisation
why:
Constructing a new 'AccountsCache' descriptor can be avoided sometimes
when the current state root is properly positioned already. Such a
feature existed already as the update function 'initStateDB()' for the
'BaseChanDB' where the accounts cache was linked into this desctiptor.
The function 'initStateDB()' was removed and re-implemented into the
'BaseVmState' constructor without optimisation. The old version was of
restricted use as a wrong accounts cache state would unconditionally
throw an exception rather than conceptually ask for a remedy.
The optimised 'BaseVmState' re-initialisation has been implemented for
the 'persistBlocks()' function.
also:
moved some test helpers to 'test/replay' folder
* Remove unused & undocumented fields from Chain descriptor
why:
Reduces attack surface in general & improves reading the code.
previously, every time the VMState was created, it will also create
new stateDB, and this action will nullify the advantages of cached accounts.
the new changes will conserve the accounts cache if the executed blocks
are contiguous. if not the stateDB need to be reinited.
this changes also allow rpcCallEvm and rpcEstimateGas executed properly
using current stateDB instead of creating new one each time they are called.
The common forks list was already used, redirected via `vm_forks` for
historical compatibility. Remove the old `vm_forks` now and divert all imports
to the common forks list outside the EVM.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
File `vm_types2` is obsolete. Remove this file and divert all imports to the
common forks list outside the EVM, or in some cases they don't need it anyway.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
Fork names were originally capitalized, and were made lower case by @narimiran
in commit 36a7519 to satisfy `parseEnum` in some tests. Restore the
capitalization and make the tests work with it.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
Move the EVM setup and call in `macro_assembler` (`runVM`) entirely to new
function `asmCallEvm` in `call_evm`. Extra return values needed for
testing are returned specially from `asmCallEvm`.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
The second `asmSetupComputation looks up state by block number and preceding
block number, modifies the first transaction with code for testing, and uses
some parts of that transaction to setup an an EVM test.
Signed-off-by: Jamie Lokier <jamie@shareable.org>
In the `macro_assembler` test code, `initComputation` is another variant of
`rpcSetupComputation` and `txSetupComputation` with slightly different
paremeters. The similarity is obvious.
It is a special setup for testing, though, as it requires a contract-creation
transaction for parameters, but sets up a `CALL` execution not `CREATE`.
Gather this into `call_evm`: `initComputation` -> `asmSetupComputation`.
Signed-off-by: Jamie Lokier <jamie@shareable.org>