Commit Graph

91 Commits

Author SHA1 Message Date
jangko 94a94c5b65 implement better hardfork management 2022-12-02 13:51:42 +07:00
Adam Spitz e040e2671a
Added basic async capabilities for vm2. (#1260)
* 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.
2022-11-01 11:35:46 -04:00
jangko 4b142ac52d
upgrade evmc to v10.0.0
fixes #1172, fixes #950
2022-10-03 16:38:32 +07:00
jangko a4678a041d
wire evmc to vm2 and drop legacy vm
fixes #445, #1172
2022-09-26 15:16:28 +07:00
Jacek Sieka c2ed731fa5
eth: adapt to smaller eth_types (#1210) 2022-09-03 20:15:35 +02:00
Jordan Hrycaj 58e0543920
Squashed snap-sync-preview patch (#1076)
* Squashed snap-sync-preview patch

why:
  Providing end results makes it easier to have an overview.

  Collected patch set comments are available as nimbus/sync/ChangeLog.md
  in chronological order, oldest first.

* Removed some cruft and obsolete imports, normalised logging
2022-05-09 15:04:48 +01:00
jangko f2f204293e
first step into styleCheck fixes 2022-04-14 08:39:50 +07:00
jangko 28cdfcaf6b
fix EIP-4399 'random' opcode
- fix previous implementation of EIP-4399
- now `random` opcode can be used with evmc_enabled
2022-02-08 20:23:40 +07:00
jangko 71aa7e4b5c EIP-4399 implementation of nim-vm
what's new:
- `RANDOM` OPCODE
- `random` field of BlockHeader(previously `mixDigest`)
- `PostMerge` temporary name
2022-02-01 18:11:14 +02:00
Jordan Hrycaj 261c0b51a7
Redesign of BaseVMState descriptor (#923)
* 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.
2022-01-18 16:19:32 +00:00
Jamie Lokier 6a7803a9e4
EVMC: Improve `--evm`, remove it in non-EVMC builds, change imports
- Remove the `--evm` option on non-EVMC builds.
  `when` around an option doesn't work with confutils; it fails to compile.
  Workaround that by setting the `ignore` pragma on EVMC-specific options.
  (Thanks @jangko for that new pragma).  I prefer this to a solution which
  moves the whole option's pragma elsewhere, especially if we add more options.

- Improve the help text, so that it shows the standard library extension on
  each target platform (or none if on another platform).

- Undo b3f21bf4 "add missing evmc_enabled conditional compilation in
  evmc_dynamic_loader".  Move the conditional to `nimbus.nim`, and take more
  care there to only use the loader function in EVMC builds.

  It's ok to just not include this EVMC-only module (like some other EVMC
  modules), rather than making the module itself a bit broken: Without this
  change, it references a function that's not imported or linked to, and it
  only links because there is no call sequence reaching that function.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-12-14 15:51:09 +00:00
jangko b3f21bf40c
add missing evmc_enabled conditional compilation in evmc_dynamic_loader 2021-12-12 16:32:13 +07:00
Jamie Lokier cf49b8d4fc
EVMC: Option `--evm`, load third-party EVM as a shared library
This patch adds:

- Load and use a third-party EVM in a shared library, instead of Nimbus EVM.
- New option `--evm` to specify which library to load.
- The library and this loader conforms to the [EVMC]
  (https://evmc.ethereum.org/) 9.x specification.

Any third-party EVM which is compatible with EVMC version 9.x and supports EVM1
contract code will be accepted.  The operating system's shared library format
applies.  These are `.so*` files on Linux, `.dll` files on Windows and `.dylib`
files on Mac.

The alternative EVM can be selected in two ways:

- Nimbus command line option `--evm:<path>`.
- Environment variable `NIMBUS_EVM=<path>`.

The reason for an environment variable is this allows all the test programs to
run with a third-party EVM as well.  Some don't parse command line options.

There are some limitations to be aware of:

- The third-party EVM must use EVMC version 9.x, no other major version.
  EVMC 9.x supports EIP-1559 / London fork and older transactions.

- Nested `*CALL` and `CREATE*` operations don't use the third-party EVM yet.
  These call the built-in Nimbus EVM.  This mixing of different EVMs between
  levels is explicitly allowed in specs, so there is no problem doing it.

- The third-party EVM doesn't need to support precompiles, because those are
  nested calls, which use the built-in Nimbus EVM.

- Third-party EVMs execute contracts correctly, but fail the final `rootHash`
  match.  The reason is that some account state changes, which are correct, are
  currently inside the Nimbus EVM and need to be moved to EVMC host logic.
  *This is a known work in progress*.  The EVM execution itself is fine.

Test results using "evmone" third-party EVM:

- [evmone](https://github.com/ethereum/evmone) has been tested.  Only on
  Linux but it "should" work on Windows and Mac equally well.

- [Version 0.8.1](https://github.com/ethereum/evmone/releases/tag/v0.8.1) was
  used because it is compatible with EVMC 9.x, which is required for the
  EIP-1559 / London fork, which Nimbus supports.  Version 0.8.0 could be used
  but it looks like an important bug was fixed in 0.8.1.

- evmone runs fine and the trace output looks good.  The calls and arguments
  are the same as the built-in Nimbus EVM for tests that have been checked
  manually, except evmone skips some calls that can be safely skipped.

- The final `rootHash` is incorrect, due to the *work in progress* mentioned
  above which is not part of the evmone execution.  Due to this, it's possible
  to try evmone and verify expected behaviours, which also validates our own
  EVMC implementation, but it can't be used as a full substitute yet.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-12-10 16:32:18 +00:00
Jamie Lokier 072934272b
Transaction: Map `evmc_result` back to `Computation` result
This missing part of EVMC processing allows third-party EVMs to work.

It fixes EVMC result processing (at the top-level of calls, not nested calls)
to use the EVMC result object, instead of reading so much internal state of the
Nimbus `Computation` object.

It has been tested by calling [`evmone`](https://github.com/ethereum/evmone)
and getting useful results with tracing enabled (`showTxCalls = true`).  It's
even able to run parts of the fixtures test suite.

There are other issues with account balances, etc that need to be worked on to
get the correct _final_ results, but the EVM execution is correct with this.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-12-10 16:27:53 +00:00
Jamie Lokier 6ef9bfd21b
EVMC: Byte-endian conversions for 256-bit numeric values
Perform byte-endian conversion for 256-bit numeric values, but not 256-bit
hashes.  These conversions are necessary for EVMC binary compatibility.

In new EVMC, all host-side conversions are explicit, calling `flip256`.

These conversions are performed in the EVMC "glue" code, which deals with the
binary interface, so the host services aren't aware of conversions.

We intend to skip these conversions when Nimbus host calls Nimbus EVM, even
when it's a shared library, using a negotiated EVMC extension.  But for now
we're focused on correctness and cross-validation with third party EVMs.

The overhead of endian conversion is not too high because most EVMC host calls
access the database anyway.  `getTxContext` does not, so the conversions from
that are cached here.  Also, well-optimised EVMs don't call it often.

It is arguable whether endian conversion should occur for storage slots (`key`).

In favour of no conversion: Slot keys are 32-byte blobs, and this is clear in
the EVMC definition where slot keys are `evmc_bytes32` (not `evmc_uint256be`),
meaning treating as a number is _not_ expected by EVMC.  Although they are
often small numbers, sometimes they are a hash from the contract code plus a
number.  Slot keys are hashed on the host side with Keccak256 before any
database calls, so the host side does not look at them numerically.

In favour of conversion: They are often small numbers and it is helpful to log
them as such, rather than a long string of zero digits with 1-2 non-zero.  The
representation in JSON has leading zeros removed, like a number rather than a
32-byte blob.  There is also an interesting space optimisation when the keys
are used unhashed in storage.

Nimbus currently treats slot keys on the host side as numbers, and the tests
pass when endian conversion is done.  So to remain consistent with other parts
of Nimbus we convert slot keys.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-12-10 16:23:27 +00:00
jangko 960539df81
unify evm call for both json-rpc and graphql
also fixes rpcEstimateGas for both of json-rpc and graphql
2021-10-31 12:24:40 +07:00
jangko baf508f6ae
move stateDB from VMState to chainDB
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.
2021-10-28 18:57:08 +07:00
jangko d93a8bc4a1
make macro_assembler to use the same testEvmCall
it also allow the macro_assembler to write more test
of CALL and CREATE family which previously not possible
2021-10-14 15:10:12 +07:00
jangko 71273f2f4c
remove error field from evm CallResult 2021-10-14 15:10:12 +07:00
jangko 08f8652790
remove noTransfer field from evm CallParams 2021-10-14 15:10:11 +07:00
jangko eb2251ec37
simplify evm call of test_precompiles
first step towards evm call variation reduction
2021-10-14 15:10:11 +07:00
jangko 69f2a0f95a
config: replace stdlib parseOpt with nim-confutils
fixes #581
2021-09-18 17:34:46 +07:00
bmoo b09ad5cacb
code cleanup removed unused imports 2021-08-18 10:35:36 +07:00
Jamie Lokier 8fcd8354b1
EVMC: Use the same host interface for nested calls as top-level
Prior to this patch, top-level EVM executions and nested EVM executions did
their `getStorage` and other requests using a completely different set of host
functions.  It was just unfinished, to get top-level "new" EVMC working.

This finishes the job - it stops using the old methods.  Effect:

- Functionality added at the EVMC host level will be used by all EVM calls.
  (The target here is Beam Sync).

- The old set of functions are no longer used, so they can be removed.

- When EVMC host call tracing is enabled (`showTxCalls = true`), it traces
  the calls from nested EVM executions as well as top-level.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-08-17 17:18:26 +01:00
Jamie Lokier b783756ff3
EVMC: Make `hostInterface` a statically initialised global
We've been filling a "vtable"-like at run time, but it's not necessary.

The new object is a global `let x = evmc_host_interface(...)`, we assume it's
initialised before the first use, and we take its address with `.unsafeAddr`.

(If we use `ref evmc_host_interface`, Nim decides (correctly) that the
functions which use it aren't GC-safe because it's a global.)

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-08-17 17:18:26 +01:00
Jamie Lokier 3047c839dc
EVMC: Improve host call tracing and fix nested call C stack usage
This combines two things, a C stack usage change with EVM nested calls
via EVMC, and changes to host call tracing.

Feature-wise, the tracing is improved:

- Storage keys and values are make more sense.
- The message/result/context objects are shown with all relevant fields.
- `call` trace is split into entry/exit, so these can be shown around the
  called contract's operations, instead of only showing the `call` parameters
  after the nested call is finished.
- Nested calls are indented, which helps to highlight the flow.
- C stack usage considerably reduced in nested calls when more functionality
  is enabled (either tracing here, or other things to come).

This will seem like a minor patch, but C stack usage was the real motivation,
after plenty of time in the debugger.

Nobody cares about stack when `showTxCalls` (you can just use a big stack when
debugging).  But these subtle changes around the `call` path were found to be
necessary for passing all tests when the EVMC nested call code is completed,
and that's a prerequisite for many things: async EVM, dynamic EVM, Beam Sync,
and to fix https://github.com/status-im/nimbus-eth1/issues/345.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-08-12 07:48:56 +07:00
Jamie Lokier 74f53c7761
EVMC: Add missing EIP-2929 (Berlin) functions to EVMC host
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>
2021-08-11 19:47:34 +07:00
Jamie Lokier 11f03a1846
Transaction: EVMC fix, `CREATE2` salt is a 256-bit blob not a number
This changes fixes a bug in `CREATE2` ops when used with EVMC.
Because it changes the salt type, it affects non-EVMC code as well.

The salt was passed through EVMC with the wrong byte order, although this went
unnoticed as the Nimbus host flipped the byte order before using it.

This was found when running Nimbus with third-party EVM,
["evmone"](https://github.com/ethereum/evmone).

There are different ways to remedy this.

If treated as a number, Nimbus EVM would byte-flip the value when calling EVMC,
then Nimbus host would flip the received value.  Finally, it would be flipped a
third time when generating the address in `generateSafeAddress`.  The first two
flips can be eliminated by negotiation (like other numbers), but there would
always be one flip.

As a bit pattern, Nimbus EVM would flip the same way it does when dealing with
hashes on the stack (e.g. with `getBlockHash`).  Nimbus host wouldn't flip at
all - and when using third-party EVMs there would be no flips in Nimbus.

Because this value is not for arithmetic, any bit pattern is valid, and there
shouldn't be any flips when using a third-party EVM, the bit-pattern
interpretation is favoured.  The only flip is done in Nimbus EVM (and might be
eliminated in an optimised version).

As suggested, we'll define a new "opaque 256 bits" type to hold this value.
(Similar to `Hash256`, but the salt isn't necessarily a hash.)

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-08-05 10:35:52 +01:00
jangko 697b38b844
EIP-3529: Replace SSTORE_CLEARS_SCHEDULE in evmc host_service 2021-06-30 20:35:10 +07:00
jangko 472e4457e3
EIP-3529: Reduce the max gas refunded after a transaction
Previously max gas refunded was defined as gas_used div 2.
Here we name the constant 2 as MAX_REFUND_QUOTIENT and
change its value to 5.

The new equation will be: gas_used div MAX_REFUND_QUOTIENT
2021-06-29 07:37:17 +07:00
jangko 05e9b891f0
EIP-3198: add baseFee op code in nim-evm 2021-06-29 07:35:16 +07:00
jangko 4a188788bd
preparation for EIP-1559 implementation
- unify signTx in test_helper and signTransaction in rpc_utils
  and put it into transaction.nim
- clean up mess by previous EIP-2930
2021-06-29 07:33:48 +07:00
Jamie Lokier 6d4205b0b0
Transaction: Just enough support to work with nested calls
Proper nested call functionality is being skipped in this iteration of new EVMC
host code to keep it simpler, to allow testing and architecture to be built
around the less complicated non-nested cases first.

Instead, nested calls use the old `Computation` path, and bypass any
third-party EVM that may be loaded.  The results are the same, and mixing
different EVMs in this way is actually permitted in the EVMC specification.

This approach also means third-party EVMs we test don't need to support
precompiles and we don't need to specially handle those cases.
(E.g. "evmone" doesn't support precompiles, just EVM1 opcodes).

(These before/after scope actions are approximately copy-pasted from
`nimbus/vm/evmc_host.nim`, making their detailed behaviour "obviously correct".
Of course they are subject to tests as well.  The small stack property of
a3c8a5c3 "EVMC: Small stacks when using EVMC, closes #575 (segfaults)" is
carefully retained.)

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:41 +01:00
Jamie Lokier 97b4aa5619
Transaction: Calculate EIP-1283/2200/2929 gas refund in `setStorage`
Make the host service `setStorage` calculate the gas refund itself, instead of
depending on EVM internals.

In EVMC, host `setStorage` is responsible for adding the gas refund using the
rules of EIP-1283 (Constantinople), EIP-2200 (Istanbul) or EIP-2929 (Berlin).

It is not obvious that the host must do it from EVMC documentation, but it's
how it has to be.  Note, this is very different from the gas _cost_, which the
host does not calculate.

Gas refund doesn't affect computation.  It is applied after the whole
transaction is complete, so it can be tracked on the host or EVM side.  But
`setStorage` doesn't return enough information for the EVM to calculate the
refund, so the host must do it when `setStorage` is used.

For now, this continues using Nimbus `Computation` just to hold the gas refund,
to fit around existing structures and get new EVMC working.  But the host can't
keep using `Computation`, so gas refund will be moved out of it in due course.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:40 +01:00
Jamie Lokier eb52fd3906
Transaction: Make `emitLog` use `Computation` to pass tests
When processing log operations on the EVMC host side, it causes incorrect
`rootHash` results in some tests.  This patch fixes the results.

The cause of these results is known: `Computation` is still doing parts of
contract scope entry/exit which need to be moved to the host.  For now, as a
temporary workaround, update logs in `Computation` as it did before.

This makes test pass when using Nimbus EVM.  (It breaks third-party EVMs when
`LOG*` ops are used, although most other tests pass.)

We can't keep this as it prevents complete host/EVM separation, but it's useful
in the current code, and it's fine to develop other functionality on top.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:40 +01:00
Jamie Lokier ce0c13c4ca
Transaction: Make `selfDestruct` use `Computation` to pass tests
When processing self destructs on the EVMC host side, it causes incorrect
`rootHash` results in some tests.  This patch fixes the results.

The cause of these results is known: `Computation` is still doing parts of
contract scope entry/exit which need to be moved to the host.  For now, as a
temporary workaround, update self destructs in `Computation` as it did before.

This makes test pass when using Nimbus EVM.  (It breaks third-party EVMs when
`SELFDESTRUCT` ops are used, although most other tests pass.)

We can't keep this as it prevents complete host/EVM separation, but it's useful
in the current code, and it's fine to develop other functionality on top.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:40 +01:00
Jamie Lokier b734240291
Transaction: Fix bounds error getting data address in empty seq
In the unusual case where log data is zero-length, `data[0].addr` is invalid
and Nim thoughtfully raises `IndexOutOfBounds`, a `Defect` so it's not even
in `CatchableError`.

This is done in the EVMC host services to handle `LOG*` ops, and it made one
of the EVM tests silently fail with no error message.  The fix is obvious.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:40 +01:00
Jamie Lokier a5dc0bd283
EVMC: Using `{.show.}` trace all calls from the host into the EVM
Show calls from the host into the EVM.  Shows the call, `evmc_message` fields,
and `evmc_result` fields when the call returns.

(When `show_tx_calls` is manually set to true.)

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:40 +01:00
Jamie Lokier ffd34a69fe
EVMC: Using `{.show.}` trace all calls from EVM to host services
When `show_tx_calls` is manually set to true, show all the calls from the EVM
to the host, including name, arguments and results.

For example this shows each call to `setStorage`, the key, value and storage
result.  This output allows the externally-visible activity of an EVM to be
seen, and it's been useful for guessing what went wrong when a test fails.

In theory, if two EVMs show the same activity in this log, they should have the
same effect on account states, gas, etc. and the same final `roothash`
(which is the only value some tests check).

ps. Ideally we'd use `{.push show.}`...`{.pop.}`, just like with `inline`.
But we can't: https://github.com/nim-lang/Nim/issues/12867

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:40 +01:00
Jamie Lokier 43b66a3a05
EVMC: `{.show.}` pragma to show EVMC host call arguments and results
New pragma `{.show.}` on a proc definition turns on tracing for that proc.
Every call to it shows the name, arguments and results, if `show_tx_calls` is
manually set to true.  This is to trace calls from EVM to host.

This started as a template which took a block expression, but the closure it
used led to illegal capture errors.  It was easier to write a macro.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:40 +01:00
Jamie Lokier 0e2bc8408d
Transaction: Run all computations via EVMC `execute`
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>
2021-06-08 18:29:39 +01:00
Jamie Lokier e8a79e7246
EVMC: Reference EVMC entry point so it's linked into the program
Even though `evmc_create_nimbus_evm` is called, it fails at link time because
the definition of that function isn't included unless it is pulled in
explicitly.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:39 +01:00
Jamie Lokier 10807bce39
EVMC: Binary compatibility on the VM side for calling `execute`
This provides the functions a loadable VM must provide for a host to use it.
The main access to a loaded EVM is `evmc_create_nimbus_evm`, and this meant to
be the only exported function the caller starts with.

That provides access to other functions, also defined in this patch, to
configure the EVM and then the key interesting function is `execute`.

`execute` runs a full computation, here using Nimbus EVM `Computation`.

(Note, even though everything is EVMC binary-compatible, there is a small
dependency on `TransactionHost` in `execute` here, which prevents this being
used by a host that is not Nimbus at the moment.  It is necessary for some
tests, and will eventually go away.)

Although this provides the VM-side functionality needed by the host, it does
not contain the glue functions for `Computation` to call the host, which are
already part of the Nimbus EVM in `nimbus/vm/evmc_api.nim`.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:39 +01:00
Jamie Lokier 0b19f42158
EVMC: Binary compatibility glue on the host side
1. This provides the necessary type adjustments for host services to be
   (optionally) callable via the EVMC binary-compatible interface.  This layer
   is stashed away in a glue module so the host services continue to use
   appropriate Nim types, and are still callable directly.

   Inlining is used to ensure there should be no real overhead, including stack
   frame size for the `call` function.  Note, `import` must be used for
   `{.inline.}` to work effectively.

2. This also provides a key call in the other direction, the version of host to
   EVM `execute` that is called on the host side.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:39 +01:00
Jamie Lokier d49fa0bb86
Transaction: Add "host services", accessors to host state from EVM
This provides "host services", functions provided by the application to an EVM.
They are a key part of EVMC compatibility, but we will switch to using these
with "native" EVM as well.

These are functions like `getStorage`, `setStorage` and `emitLog` for accessing
the account state, because the EVM is not allowed direct access to the database.

This code is adapted from `nimbus/vm/evmc_host.nim` and other places, but there
is more emphasis on being host-side only, no dependency on the EVM or
`Computation` type.  It uses `TransactionHost` and types in `host_types`.

These host services have two goals: To be compatible with EVMC, and to be a
good way for the Nimbus EVM to access the data it needs.  In our new Nimbus
internal architecture, the EVM will only access the databases and other
application state via these host service functions.

The reason for containing the EVM like this, even "native" EVM, is that having
one good interface to the data makes it a lot easier to change how the database
works, which is on the roadmap.

These functions almost have EVMC signatures, but they are not binary compatible
with EVMC.  (Binary compatibility is provided by another module).  It would be
fine for Nimbus EVM to call these functions directly when linked directly.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 18:29:39 +01:00
Jamie Lokier aee0fe39d2
EVM: Remove `vm_types2` everywhere, use common forks list instead
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>
2021-06-08 15:36:31 +01:00
Jamie Lokier b3a788c7ce
Transaction: Move contract address generation outside the EVM
The current EVM generates its own new contract addresses, and this is why there
are separate `msg.contractAddress` and `msg.codeAddress` fields in the
computation start message.

In EVMC, account updates are only allowed on the host side, including contract
generation, and the start message has one destination field, `msg.destination`.
The EVM cannot select addresses, only use them.  It's a sensible design.

The difference makes the current EVM incompatible with EVMC and its message
format, so this patch corrects the difference.  It moves contract address
generation to the host side.  This simplifies the EVM and its API a little.

(As an API change, this is incompatible with vm2, so it's guarded under
`evmc_enabled` to allow vm2 to continue to build and run at this time.  This is
also why there are fewer deletions than would otherwise be expected.)

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-08 15:36:30 +01:00
Jamie Lokier 5e718bcbe2
EVM: Remove most unused imports of `vm_*` files
Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-01 16:54:38 +01:00
Jamie Lokier beb750b8df
Transaction: Remove no longer used `setupComputation`
The last caller of `setupComputation` is gone, now that it's been replaced by
the single entry point for all EVM calls, `runComputation`.

With this removal, EVM's `Computation` type should no longer be used anywhere
outside the call module (except in some tests and the EVM itself).

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-01 16:54:34 +01:00
Jamie Lokier 8b4f5a1103 Transaction: Change transactions to go through unified EVM runner
Simplify transaction validations to use `runComputation`; drop other code.

Getting everything right up to this point to pass all the tests was trickier
than it looks.

Signed-off-by: Jamie Lokier <jamie@shareable.org>
2021-06-01 18:40:41 +03:00