The mux tracer never exposed OnNonceChangeV2 or OnCodeChangeV2 on the
Hooks struct it returns. A child tracer that only implements the V2
variants (which include a reason parameter - CodeChangeReason /
NonceChangeReason) silently received no events when wrapped behind the
mux.
Worse, OnCodeChangeV2 had a fanout method defined (added in #33148) but
was never wired into the outer Hooks{} literal, so it was dead code.
OnNonceChangeV2 had neither the fanout nor the wire.
Mirror the precedence already used in core/state_processor.go and the
OnSystemCall fix from #34862: expose only the V2 variants on the Hooks
struct, and have the fanout prefer each child's V2 hook, falling back
to V1 when only V1 is set. Exposing both V1 and V2 simultaneously would
have tripped the "cannot have both" guard in WrapWithJournal and made
statedb_hooked pick only V2 (so V1-only children would still lose
events).
Callers: a child tracer registered via muxTracer config that tracks
nonce changes with NonceChangeReason (e.g. to detect EIP-7702
authorizations vs contract creation) or code changes with
CodeChangeReason (e.g. to filter self-destruct from creation) was
functionally broken - no events reached the child at all for
OnNonceChangeV2, and OnCodeChangeV2 specifically became dead code
after #33148.
Add a regression test covering both V2-only and V1-only children.
The mux tracer fanned out every standard hook to its children but never
forwarded OnSystemCall{Start,End}. Tracers that rely on these - like
`logger.jsonLogger`, which uses the start hook to silence its opcode
hook for the duration of a system call - never got the signal when
wrapped behind a mux.
In evm t8n, combining `--trace` with `--opcode-count` (default for geth
with exec specs) produces exactly that wrapping. The first system call
(e.g. `ProcessBeaconBlockRoot`) then fires `OnOpcode` on the json logger
before any `OnTxStart` has run, dereferencing a nil env and crashing
t8n.
Forward both hooks through the mux. The V2 fan-out falls back to V1 for
children that only implement the legacy hook, mirroring the precedence
already used in `core/state_processor.go`.
Adds `--opcode.count=<file>` flag to `evm t8n` that writes per-opcode
execution frequency counts to a JSON file (relative to
`--output.basedir`).
---------
Co-authored-by: MariusVanDerWijden <m.vanderwijden@live.de>
Co-authored-by: Sina Mahmoodi <itz.s1na@gmail.com>
While updating to latest Geth, I noticed `OnCodeChangeV2` was not
properly handled in `SelfDestruct/6780`, this PR fixes this and bring a
unit test. Let me know if it's deemed more approriate to merge the tests
with the other one.
Breaking changes:
- The ChainConfig was exposed to tracers via VMContext passed in
`OnTxStart`. This is unnecessary specially looking through the lens of
live tracers as chain config remains the same throughout the lifetime of
the program. It was there so that native API-invoked tracers could
access it. So instead we moved it to the constructor of API tracers.
Non-breaking:
- Change the default config of the tracers to be `{}` instead of nil.
This way an extra nil check can be avoided.
Refactoring:
- Rename `supply` struct to `supplyTracer`.
- Un-export some hook definitions.
Here we add a Go API for running tracing plugins within the main block import process.
As an advanced user of geth, you can now create a Go file in eth/tracers/live/, and within
that file register your custom tracer implementation. Then recompile geth and select your tracer
on the command line. Hooks defined in the tracer will run whenever a block is processed.
The hook system is defined in package core/tracing. It uses a struct with callbacks, instead of
requiring an interface, for several reasons:
- We plan to keep this API stable long-term. The core/tracing hook API does not depend on
on deep geth internals.
- There are a lot of hooks, and tracers will only need some of them. Using a struct allows you
to implement only the hooks you want to actually use.
All existing tracers in eth/tracers/native have been rewritten to use the new hook system.
This change breaks compatibility with the vm.EVMLogger interface that we used to have.
If you are a user of vm.EVMLogger, please migrate to core/tracing, and sorry for breaking
your stuff. But we just couldn't have both the old and new tracing APIs coexist in the EVM.
---------
Co-authored-by: Matthieu Vachon <matthieu.o.vachon@gmail.com>
Co-authored-by: Delweng <delweng@gmail.com>
Co-authored-by: Martin HS <martin@swende.se>
This makes non-JS tracers execute all block txs on a single goroutine.
In the previous implementation, we used to prepare every tx pre-state
on one goroutine, and then run the transactions again with tracing enabled.
Native tracers are usually faster, so it is faster overall to use their output as
the pre-state for tracing the next transaction.
Co-authored-by: Sina Mahmoodi <itz.s1na@gmail.com>
This removes the 'time' field from logs, as well as from the tracer interface. This change makes the trace output deterministic. If a tracer needs the time they can measure it themselves. No need for evm to do this.
Co-authored-by: Sina Mahmoodi <itz.s1na@gmail.com>
