execution/vm: optimize KZG point evaluation precompile (~24% faster)

[yperbasis]

Part of #14522

Summary

• Use optimized go-eth-kzg with JointScalarMultiplication (Strauss-Shamir) and PairingCheckFixedQ (precomputed Miller loop lines) for the EIP-4844 point evaluation precompile
• Eliminates the G2 scalar multiplication, replaces two G1 scalar muls with one joint, and uses precomputed pairing lines for the fixed G2 points
• Upstream PR: Optimize Verify with JointScalarMultiplication and PairingCheckFixedQ crate-crypto/go-eth-kzg#131 — replace directive to be removed once merged and tagged

Benchmark (Apple M2 Max)

name                                    old time/op    new time/op    delta
PrecompiledPointEvaluation/Gas=50000      1.287ms        0.978ms      -24%

name                                    old mgas/s     new mgas/s     delta
PrecompiledPointEvaluation/Gas=50000      38.9           51.0         +31%

name                                    old allocs/op  new allocs/op  delta
PrecompiledPointEvaluation/Gas=50000      47             30           -36%

name                                    old bytes/op   new bytes/op   delta
PrecompiledPointEvaluation/Gas=50000      6424           4488         -30%

Test plan

• go test -run TestPrecompiledPointEvaluation ./execution/vm/
• All go-eth-kzg consensus spec tests pass
• CI

🤖 Generated with Claude Code

[chfast]

Really cool. I guess we wait for the upstream review?

[yperbasis]

Really cool. I guess we wait for the upstream review?

I think we can use the optimization in branch main of erigon even before it's upstreamed to go-eth-kzg, given that the tests passed and we'll have time to test it further before cutting release 3.5.

[Giulio2002]

LGTM — dependency bump replacing go-eth-kzg with erigontech fork for KZG optimization, go.mod/go.sum only

[Copilot]

Pull request overview

This PR aims to speed up the EIP-4844 KZG point evaluation precompile by switching the build to an optimized go-eth-kzg implementation (via a go.mod replace to an erigontech fork/pinned commit).

Changes:

• Add a replace directive to redirect github.com/crate-crypto/go-eth-kzg to github.com/erigontech/go-eth-kzg at a specific pseudo-version.
• Update go.sum to reflect the new module source and remove the old sums for the replaced module.

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated 2 comments.

File	Description
go.mod	Adds a replace override for go-eth-kzg to use an erigontech fork/pinned commit.
go.sum	Removes sums for the old crate-crypto module version and adds sums for the replacement module version.

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[Copilot]

The PR title/description describes runtime changes to the EIP-4844 point evaluation precompile, but this diff only introduces a module replacement. If the precompile optimizations are part of this PR, include the corresponding code changes; otherwise update the PR title/description to reflect that this is a dependency override only.

[Copilot]

This replace directive is impactful and currently lacks any in-file context (e.g., why a fork is needed and when it should be removed). Consider adding an inline comment with the upstream PR/link and grouping this replace near the existing replace directives at the top of the file to keep go.mod structure consistent.