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Merged
edg-l merged 5 commits into from
Jun 3, 2026
Merged

perf(l1): short-circuit KECCAK256 on empty input #6775

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3d0432c
perf(l1): short-circuit KECCAK256 on empty input
edg-l Jun 2, 2026
8ef02c2
refactor(l1): address review on KECCAK256 empty-input fast path
edg-l Jun 3, 2026
4c99952
refactor(l1,l2): fix EMPTY_KECCACK_HASH typo -> EMPTY_KECCAK_HASH
edg-l Jun 3, 2026
f43eb32
docs: changelog entry for KECCAK256 empty-input fast path
edg-l Jun 3, 2026
5b824f8
Merge branch 'main' into perf/keccak-empty-input
edg-l Jun 3, 2026
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4 changes: 4 additions & 0 deletions CHANGELOG.md
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Expand Up @@ -8,6 +8,10 @@

## Perf

### 2026-06-03

- Short-circuit the `KECCAK256` opcode on zero-length input by returning the precomputed `keccak256("")` constant, skipping the permutation [#6775](https://github.com/lambdaclass/ethrex/pull/6775)

### 2026-05-27

- Prefetch all BAL storage synchronously before execution [#6732](https://github.com/lambdaclass/ethrex/pull/6732)
Expand Down
8 changes: 4 additions & 4 deletions crates/blockchain/vm.rs
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@@ -1,6 +1,6 @@
use ethrex_common::{
Address, H256, U256,
constants::EMPTY_KECCACK_HASH,
constants::EMPTY_KECCAK_HASH,
types::{AccountState, BlockHash, BlockHeader, BlockNumber, ChainConfig, Code, CodeMetadata},
};
use ethrex_crypto::keccak::keccak_hash;
Expand Down Expand Up @@ -210,7 +210,7 @@ impl VmDatabase for StoreVmDatabase {
fields(namespace = "block_execution")
)]
fn get_account_code(&self, code_hash: H256) -> Result<Code, EvmError> {
if code_hash == *EMPTY_KECCACK_HASH {
if code_hash == *EMPTY_KECCAK_HASH {
return Ok(Code::default());
}
match self.store.get_account_code(code_hash) {
Expand All @@ -229,9 +229,9 @@ impl VmDatabase for StoreVmDatabase {
fields(namespace = "block_execution")
)]
fn get_code_metadata(&self, code_hash: H256) -> Result<CodeMetadata, EvmError> {
use ethrex_common::constants::EMPTY_KECCACK_HASH;
use ethrex_common::constants::EMPTY_KECCAK_HASH;

if code_hash == *EMPTY_KECCACK_HASH {
if code_hash == *EMPTY_KECCAK_HASH {
return Ok(CodeMetadata { length: 0 });
}
match self.store.get_code_metadata(code_hash) {
Expand Down
2 changes: 1 addition & 1 deletion crates/common/constants.rs
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Expand Up @@ -35,7 +35,7 @@ pub static EMPTY_WITHDRAWALS_HASH: LazyLock<H256> = LazyLock::new(|| {
});

// Keccak256(""), represents the code hash for an account without code
pub static EMPTY_KECCACK_HASH: LazyLock<H256> = LazyLock::new(|| {
pub static EMPTY_KECCAK_HASH: LazyLock<H256> = LazyLock::new(|| {
H256::from_slice(
&hex::decode("c5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470")
.expect("Failed to decode hex from string"),
Expand Down
14 changes: 7 additions & 7 deletions crates/common/types/account.rs
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Expand Up @@ -15,7 +15,7 @@ use ethrex_rlp::{
};

use super::GenesisAccount;
use crate::constants::{EMPTY_KECCACK_HASH, EMPTY_TRIE_HASH};
use crate::constants::{EMPTY_KECCAK_HASH, EMPTY_TRIE_HASH};

#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, Hash)]
pub struct Code {
Expand Down Expand Up @@ -140,7 +140,7 @@ pub struct AccountStateSlimCodec(pub AccountState);
impl Default for AccountInfo {
fn default() -> Self {
Self {
code_hash: *EMPTY_KECCACK_HASH,
code_hash: *EMPTY_KECCAK_HASH,
balance: Default::default(),
nonce: Default::default(),
}
Expand All @@ -153,7 +153,7 @@ impl Default for AccountState {
nonce: Default::default(),
balance: Default::default(),
storage_root: *EMPTY_TRIE_HASH,
code_hash: *EMPTY_KECCACK_HASH,
code_hash: *EMPTY_KECCAK_HASH,
}
}
}
Expand All @@ -162,7 +162,7 @@ impl Default for Code {
fn default() -> Self {
Self {
bytecode: Bytes::new(),
hash: *EMPTY_KECCACK_HASH,
hash: *EMPTY_KECCAK_HASH,
jump_targets: Vec::new(),
}
}
Expand Down Expand Up @@ -262,7 +262,7 @@ impl RLPEncode for AccountStateSlimCodec {
struct CodeHashCodec<'a>(&'a H256);
impl RLPEncode for CodeHashCodec<'_> {
fn encode(&self, buf: &mut dyn BufMut) {
let data = if *self.0 != *EMPTY_KECCACK_HASH {
let data = if *self.0 != *EMPTY_KECCAK_HASH {
self.0.as_bytes()
} else {
&[]
Expand Down Expand Up @@ -306,7 +306,7 @@ impl RLPDecode for AccountStateSlimCodec {
impl RLPDecode for CodeHashCodec {
fn decode_unfinished(mut rlp: &[u8]) -> Result<(Self, &[u8]), RLPDecodeError> {
let value = match rlp.split_off_first() {
Some(0x80) => *EMPTY_KECCACK_HASH,
Some(0x80) => *EMPTY_KECCAK_HASH,
Some(0xA0) => {
let data;
(data, rlp) = rlp
Expand Down Expand Up @@ -376,7 +376,7 @@ impl Account {

impl AccountInfo {
pub fn is_empty(&self) -> bool {
self.balance.is_zero() && self.nonce == 0 && self.code_hash == *EMPTY_KECCACK_HASH
self.balance.is_zero() && self.nonce == 0 && self.code_hash == *EMPTY_KECCAK_HASH
}
}

Expand Down
6 changes: 3 additions & 3 deletions crates/common/types/block.rs
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Expand Up @@ -877,7 +877,7 @@ pub fn calc_excess_blob_gas(parent: &BlockHeader, schedule: ForkBlobSchedule, fo
#[cfg(test)]
mod test {
use super::*;
use crate::constants::EMPTY_KECCACK_HASH;
use crate::constants::EMPTY_KECCAK_HASH;
use crate::types::{BLOB_BASE_FEE_UPDATE_FRACTION, ELASTICITY_MULTIPLIER};
use ethereum_types::H160;
use hex_literal::hex;
Expand Down Expand Up @@ -951,7 +951,7 @@ mod test {
blob_gas_used: Some(0x00),
excess_blob_gas: Some(0x00),
parent_beacon_block_root: Some(H256::zero()),
requests_hash: Some(*EMPTY_KECCACK_HASH),
requests_hash: Some(*EMPTY_KECCAK_HASH),
..Default::default()
};
let block = BlockHeader {
Expand Down Expand Up @@ -995,7 +995,7 @@ mod test {
blob_gas_used: Some(0x00),
excess_blob_gas: Some(0x00),
parent_beacon_block_root: Some(H256::zero()),
requests_hash: Some(*EMPTY_KECCACK_HASH),
requests_hash: Some(*EMPTY_KECCAK_HASH),
..Default::default()
};
assert!(validate_block_header(&block, &parent_block, ELASTICITY_MULTIPLIER).is_ok());
Expand Down
6 changes: 3 additions & 3 deletions crates/common/types/block_execution_witness.rs
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Expand Up @@ -6,7 +6,7 @@ use crate::rkyv_utils::H256Wrapper;
use crate::serde_utils;
use crate::types::{Block, Code, CodeMetadata};
use crate::{
constants::EMPTY_KECCACK_HASH,
constants::EMPTY_KECCAK_HASH,
types::{AccountState, AccountUpdate, BlockHeader, ChainConfig},
utils::keccak,
};
Expand Down Expand Up @@ -631,7 +631,7 @@ impl GuestProgramState {
/// include every byte of code the VM reads, and EIP-8025 stateless
/// validation requires the same.
pub fn get_account_code(&self, code_hash: H256) -> Result<Code, GuestProgramStateError> {
if code_hash == *EMPTY_KECCACK_HASH {
if code_hash == *EMPTY_KECCAK_HASH {
return Ok(Code::default());
}
self.codes_hashed
Expand All @@ -646,7 +646,7 @@ impl GuestProgramState {
&self,
code_hash: H256,
) -> Result<CodeMetadata, GuestProgramStateError> {
if code_hash == *EMPTY_KECCACK_HASH {
if code_hash == *EMPTY_KECCAK_HASH {
return Ok(CodeMetadata { length: 0 });
}
self.codes_hashed
Expand Down
4 changes: 2 additions & 2 deletions crates/networking/p2p/sync/healing/state.rs
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Expand Up @@ -15,7 +15,7 @@ use std::{
time::{Duration, Instant},
};

use ethrex_common::{H256, constants::EMPTY_KECCACK_HASH, types::AccountState};
use ethrex_common::{H256, constants::EMPTY_KECCAK_HASH, types::AccountState};
use ethrex_crypto::NativeCrypto;
use ethrex_rlp::{decode::RLPDecode, encode::RLPEncode};
use ethrex_storage::Store;
Expand Down Expand Up @@ -211,7 +211,7 @@ async fn heal_state_trie(
H256::from_slice(&meta.path.concat(&node.partial).to_bytes());

// // Collect valid code hash
if account.code_hash != *EMPTY_KECCACK_HASH {
if account.code_hash != *EMPTY_KECCAK_HASH {
code_hash_collector.add(account.code_hash);
code_hash_collector.flush_if_needed().await?;
}
Expand Down
8 changes: 4 additions & 4 deletions crates/networking/p2p/sync/snap_sync.rs
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Expand Up @@ -15,7 +15,7 @@ use ethrex_blockchain::Blockchain;
use ethrex_common::types::{AccountState, BlockHeader, Code};
use ethrex_common::{
H256,
constants::{EMPTY_KECCACK_HASH, EMPTY_TRIE_HASH},
constants::{EMPTY_KECCAK_HASH, EMPTY_TRIE_HASH},
};
use ethrex_rlp::decode::RLPDecode;
use ethrex_storage::Store;
Expand Down Expand Up @@ -928,7 +928,7 @@ pub fn validate_bytecodes(store: Store, state_root: H256) -> bool {
.iter_accounts(state_root)
.expect("we couldn't iterate over accounts")
{
if account_state.code_hash != *EMPTY_KECCACK_HASH
if account_state.code_hash != *EMPTY_KECCAK_HASH
&& !store
.get_account_code(account_state.code_hash)
.is_ok_and(|code| code.is_some())
Expand Down Expand Up @@ -1012,7 +1012,7 @@ async fn insert_accounts(
let code_hashes_from_snapshot: Vec<H256> = account_states_snapshot
.iter()
.filter_map(|(_, state)| {
(state.code_hash != *EMPTY_KECCACK_HASH).then_some(state.code_hash)
(state.code_hash != *EMPTY_KECCAK_HASH).then_some(state.code_hash)
})
.collect();

Expand Down Expand Up @@ -1132,7 +1132,7 @@ async fn insert_accounts(
for account in iter {
let account = account.map_err(|err| SyncError::RocksDBError(err.into_string()))?;
let account_state = AccountState::decode(&account.1).map_err(SyncError::Rlp)?;
if account_state.code_hash != *EMPTY_KECCACK_HASH {
if account_state.code_hash != *EMPTY_KECCAK_HASH {
code_hash_collector.add(account_state.code_hash);
code_hash_collector.flush_if_needed().await?;
}
Expand Down
4 changes: 2 additions & 2 deletions crates/networking/rpc/types/block.rs
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Expand Up @@ -120,7 +120,7 @@ mod test {
use bytes::Bytes;
use ethrex_common::{
Address, Bloom, H256, U256,
constants::EMPTY_KECCACK_HASH,
constants::EMPTY_KECCAK_HASH,
types::{EIP1559Transaction, Transaction, TxKind},
};
use std::str::FromStr;
Expand Down Expand Up @@ -170,7 +170,7 @@ mod test {
blob_gas_used: Some(0x00),
excess_blob_gas: Some(0x00),
parent_beacon_block_root: Some(H256::zero()),
requests_hash: Some(*EMPTY_KECCACK_HASH),
requests_hash: Some(*EMPTY_KECCAK_HASH),
..Default::default()
};

Expand Down
4 changes: 2 additions & 2 deletions crates/storage/store.rs
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Expand Up @@ -855,10 +855,10 @@ impl Store {
/// Checks cache first, falls back to database. If metadata is missing,
/// falls back to loading full code and extracts length (auto-migration).
pub fn get_code_metadata(&self, code_hash: H256) -> Result<Option<CodeMetadata>, StoreError> {
use ethrex_common::constants::EMPTY_KECCACK_HASH;
use ethrex_common::constants::EMPTY_KECCAK_HASH;

// Empty code special case
if code_hash == *EMPTY_KECCACK_HASH {
if code_hash == *EMPTY_KECCAK_HASH {
return Ok(Some(CodeMetadata { length: 0 }));
}

Expand Down
4 changes: 2 additions & 2 deletions crates/vm/backends/levm/db.rs
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@@ -1,5 +1,5 @@
use ethrex_common::U256 as CoreU256;
use ethrex_common::constants::EMPTY_KECCACK_HASH;
use ethrex_common::constants::EMPTY_KECCAK_HASH;
use ethrex_common::types::{AccountState, Code, CodeMetadata};
use ethrex_common::{Address as CoreAddress, H256 as CoreH256};
use ethrex_levm::db::Database as LevmDatabase;
Expand Down Expand Up @@ -69,7 +69,7 @@ impl LevmDatabase for DatabaseLogger {
}

fn get_account_code(&self, code_hash: CoreH256) -> Result<Code, DatabaseError> {
if code_hash != *EMPTY_KECCACK_HASH {
if code_hash != *EMPTY_KECCAK_HASH {
let mut code_accessed = self
.code_accessed
.lock()
Expand Down
24 changes: 12 additions & 12 deletions crates/vm/backends/levm/mod.rs
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Expand Up @@ -11,7 +11,7 @@ use bytes::Bytes;
#[cfg(all(feature = "rayon", not(feature = "eip-8025")))]
use ethrex_common::H256;
#[cfg(all(feature = "rayon", not(feature = "eip-8025")))]
use ethrex_common::constants::EMPTY_KECCACK_HASH;
use ethrex_common::constants::EMPTY_KECCAK_HASH;
#[cfg(all(feature = "rayon", not(feature = "eip-8025")))]
use ethrex_common::types::Code;
#[cfg(all(feature = "rayon", not(feature = "eip-8025")))]
Expand Down Expand Up @@ -843,10 +843,10 @@ impl LEVM {
}

// Detect account removal (EIP-161): post-state empty but pre-state existed
let post_empty = balance.is_zero() && nonce == 0 && code_hash == *EMPTY_KECCACK_HASH;
let post_empty = balance.is_zero() && nonce == 0 && code_hash == *EMPTY_KECCAK_HASH;
let pre_empty = prestate.balance.is_zero()
&& prestate.nonce == 0
&& prestate.code_hash == *EMPTY_KECCACK_HASH;
&& prestate.code_hash == *EMPTY_KECCAK_HASH;
let removed = post_empty && !pre_empty;

let balance_changed = acct_changes
Expand Down Expand Up @@ -1654,7 +1654,7 @@ impl LEVM {
let seeded_hash = if seeded_pos > 0 {
let seeded_code = &acct.code_changes[seeded_pos - 1].new_code;
if seeded_code.is_empty() {
*EMPTY_KECCACK_HASH
*EMPTY_KECCAK_HASH
} else {
ethrex_common::utils::keccak(seeded_code)
}
Expand All @@ -1667,7 +1667,7 @@ impl LEVM {
store
.get_account_state(*addr)
.map(|a| a.code_hash)
.unwrap_or(*EMPTY_KECCACK_HASH)
.unwrap_or(*EMPTY_KECCAK_HASH)
})
};
if account.info.code_hash != seeded_hash {
Expand Down Expand Up @@ -1782,7 +1782,7 @@ impl LEVM {
if let Some(expected_code) = find_exact_change_code(&acct.code_changes, withdrawal_idx)
{
let code_hash = if expected_code.is_empty() {
*EMPTY_KECCACK_HASH
*EMPTY_KECCAK_HASH
} else {
ethrex_common::utils::keccak(expected_code)
};
Expand Down Expand Up @@ -1932,7 +1932,7 @@ impl LEVM {
// Code
if !has_exact_change_code(&acct.code_changes, withdrawal_idx) {
let seeded_hash = match acct.code_changes.last() {
Some(c) if c.new_code.is_empty() => *EMPTY_KECCACK_HASH,
Some(c) if c.new_code.is_empty() => *EMPTY_KECCAK_HASH,
Some(c) => ethrex_common::utils::keccak(&c.new_code),
None => {
db.store
Expand Down Expand Up @@ -2146,7 +2146,7 @@ impl LEVM {
store
.get_account_state(ac.address)
.ok()
.filter(|s| s.code_hash != *EMPTY_KECCACK_HASH)
.filter(|s| s.code_hash != *EMPTY_KECCAK_HASH)
.map(|s| s.code_hash)
})
.collect();
Expand Down Expand Up @@ -2934,7 +2934,7 @@ mod bal_tests {
AccountState {
balance: U256::from(100),
nonce: 5,
code_hash: *EMPTY_KECCACK_HASH,
code_hash: *EMPTY_KECCAK_HASH,
storage_root: H256::zero(),
},
);
Expand All @@ -2961,7 +2961,7 @@ mod bal_tests {
// Last balance entry wins
assert_eq!(info.balance, U256::from(80));
assert_eq!(info.nonce, 6);
assert_eq!(info.code_hash, *EMPTY_KECCACK_HASH);
assert_eq!(info.code_hash, *EMPTY_KECCAK_HASH);
// Storage
let key = ethrex_common::utils::u256_to_h256(U256::from(42));
assert_eq!(*u.added_storage.get(&key).unwrap(), U256::from(999));
Expand All @@ -2976,7 +2976,7 @@ mod bal_tests {
AccountState {
balance: U256::from(1000),
nonce: 0,
code_hash: *EMPTY_KECCACK_HASH,
code_hash: *EMPTY_KECCAK_HASH,
storage_root: H256::zero(),
},
);
Expand Down Expand Up @@ -3017,7 +3017,7 @@ mod bal_tests {
AccountState {
balance: U256::from(50),
nonce: 1,
code_hash: *EMPTY_KECCACK_HASH,
code_hash: *EMPTY_KECCAK_HASH,
storage_root: H256::zero(),
},
);
Expand Down
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