execution/vm: preserve EIP-4788 no-op-when-not-deployed syscall semantics

[yperbasis]

Summary

#19277 added && !syscall to the Spurious Dragon zero-value short-circuit in evm.call, causing system calls to a non-deployed target to run CreateAccount(addr, false) instead of returning a no-op. That violates EIP-4788's rule that "if the contract code is empty, the system call is a no-op", specifically at the fork-transition block where the beacon-root contract is deployed later in the same block by a CREATE tx.

Repro

On #20606 (bal-devnet-4), which flips ExperimentalBAL + Exec3Parallel on by default, the eest_blockchain suite fails:

--- FAIL: TestExecutionSpecBlockchain/cancun/eip4788_beacon_root/
          test_beacon_root_contract_deploy.json/.../deploy_on_cancun
block_test.go:62: block #[2 0 0 0] insertion into chain failed:
  BadBlock err: updateForkChoice: [4/6 Execution] invalid block,
  block=2, gas used by execution: 52529, in header: 116552

Block 1 is the first Cancun block (timestamp=15000, fork point). The EIP-4788 pre-block syscall fires before the beacon-root contract is deployed later in block 1's tx 0. Post-#19277, the syscall calls CreateAccount(0x000f3df6…, false) at the beacon-root address, diverting state so block 2's verifier tx underuses gas by ~64k.

Reverting only the !syscall clause from the short-circuit — while keeping the rest of #19277 — makes the test green without regressing TestSystemCallZeroValueSkipsTransferChecks (its target already exists, so this branch isn't exercised).

Change

execution/vm/evm.go, one hunk:

 if !exist {
-    if !isPrecompile && evm.chainRules.IsSpuriousDragon && value.IsZero() && !syscall {
+    // EIP-4788/6110/7002/7251 system calls to a non-deployed target are
+    // no-ops ... short-circuit to preserve that at the fork-transition block.
+    if !isPrecompile && evm.chainRules.IsSpuriousDragon && value.IsZero() {
         return nil, gas, nil
     }
     evm.intraBlockState.CreateAccount(addr, false)
 }

Everything else from #19277 is preserved: the zero-value CanTransfer skip, TouchAccount(caller) instead of Transfer for syscalls, and the intra_block_state.go refactor.

Validation

Local:

• cancun/eip4788_beacon_root/* — all pass (8.5s)
• Full cancun eest_blockchain suite — pass (167s)
• Full prague eest_blockchain suite — pass (85s)
• TestSystemCallZeroValueSkipsTransferChecks — pass (still green)
• execution/state + execution/stagedsync unit tests — pass
• make lint — clean

Test plan

• CI Gate green on this branch
• Rebase [DO-NOT-MERGE] bal-devnet-4 #20606 onto this and confirm race-tests / execution-eest-blockchain turns green there

Related

• Introduced by: execution/vm: disable the value transfer in syscall #19277 (cherry-pick of geth PR 33741)
• Surfaced by: [DO-NOT-MERGE] bal-devnet-4 #20606 (bal-devnet-4 defaults)

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR restores the “no-op when target is not deployed and value is zero” behavior for system calls (notably EIP-4788) by removing the && !syscall restriction from the Spurious Dragon short-circuit in EVM.call, preventing unintended account creation during fork-transition blocks.

Changes:

• Re-enable the Spurious Dragon zero-value short-circuit for system calls to non-deployed targets.
• Add an explanatory comment describing the fork-transition/system-call motivation for the short-circuit.

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