From 95d9c515d70aac7e40c3fc1582fc331254c686ae Mon Sep 17 00:00:00 2001
From: Michael Sproul <michael@sigmaprime.io>
Date: Fri, 9 Feb 2024 14:37:37 +1100
Subject: [PATCH] Use epoch cache in block packing

---
 beacon_node/beacon_chain/src/beacon_chain.rs  |  4 ++++
 beacon_node/beacon_chain/src/errors.rs        |  2 ++
 beacon_node/operation_pool/src/attestation.rs | 14 +++-----------
 3 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/beacon_node/beacon_chain/src/beacon_chain.rs b/beacon_node/beacon_chain/src/beacon_chain.rs
index 2f0da3abc53..b73b6037f7b 100644
--- a/beacon_node/beacon_chain/src/beacon_chain.rs
+++ b/beacon_node/beacon_chain/src/beacon_chain.rs
@@ -94,6 +94,7 @@ use slot_clock::SlotClock;
 use ssz::Encode;
 use state_processing::{
     common::get_attesting_indices_from_state,
+    epoch_cache::initialize_epoch_cache,
     per_block_processing,
     per_block_processing::{
         errors::AttestationValidationError, get_expected_withdrawals,
@@ -4810,7 +4811,10 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
         let attestation_packing_timer =
             metrics::start_timer(&metrics::BLOCK_PRODUCTION_ATTESTATION_TIMES);
 
+        // Epoch cache and total balance cache are required for op pool packing.
         state.build_total_active_balance_cache_at(state.current_epoch(), &self.spec)?;
+        initialize_epoch_cache(&mut state, &self.spec)?;
+
         let mut prev_filter_cache = HashMap::new();
         let prev_attestation_filter = |att: &AttestationRef<T::EthSpec>| {
             self.filter_op_pool_attestation(&mut prev_filter_cache, att, &state)
diff --git a/beacon_node/beacon_chain/src/errors.rs b/beacon_node/beacon_chain/src/errors.rs
index 6d2a178faa7..a4f694e411f 100644
--- a/beacon_node/beacon_chain/src/errors.rs
+++ b/beacon_node/beacon_chain/src/errors.rs
@@ -256,6 +256,7 @@ pub enum BlockProductionError {
     UnableToProduceAtSlot(Slot),
     SlotProcessingError(SlotProcessingError),
     BlockProcessingError(BlockProcessingError),
+    EpochCacheError(EpochCacheError),
     ForkChoiceError(ForkChoiceError),
     Eth1ChainError(Eth1ChainError),
     BeaconStateError(BeaconStateError),
@@ -296,3 +297,4 @@ easy_from_to!(SlotProcessingError, BlockProductionError);
 easy_from_to!(Eth1ChainError, BlockProductionError);
 easy_from_to!(StateAdvanceError, BlockProductionError);
 easy_from_to!(ForkChoiceError, BlockProductionError);
+easy_from_to!(EpochCacheError, BlockProductionError);
diff --git a/beacon_node/operation_pool/src/attestation.rs b/beacon_node/operation_pool/src/attestation.rs
index 9133157dbe8..8d8e3796745 100644
--- a/beacon_node/operation_pool/src/attestation.rs
+++ b/beacon_node/operation_pool/src/attestation.rs
@@ -2,7 +2,7 @@ use crate::attestation_storage::AttestationRef;
 use crate::max_cover::MaxCover;
 use crate::reward_cache::RewardCache;
 use state_processing::common::{
-    altair, base, get_attestation_participation_flag_indices, get_attesting_indices,
+    base, get_attestation_participation_flag_indices, get_attesting_indices,
 };
 use std::collections::HashMap;
 use types::{
@@ -30,7 +30,7 @@ impl<'a, T: EthSpec> AttMaxCover<'a, T> {
         if let BeaconState::Base(ref base_state) = state {
             Self::new_for_base(att, state, base_state, total_active_balance, spec)
         } else {
-            Self::new_for_altair_deneb(att, state, reward_cache, total_active_balance, spec)
+            Self::new_for_altair_deneb(att, state, reward_cache, spec)
         }
     }
 
@@ -72,7 +72,6 @@ impl<'a, T: EthSpec> AttMaxCover<'a, T> {
         att: AttestationRef<'a, T>,
         state: &BeaconState<T>,
         reward_cache: &'a RewardCache,
-        total_active_balance: u64,
         spec: &ChainSpec,
     ) -> Option<Self> {
         let att_data = att.attestation_data();
@@ -81,8 +80,6 @@ impl<'a, T: EthSpec> AttMaxCover<'a, T> {
         let att_participation_flags =
             get_attestation_participation_flag_indices(state, &att_data, inclusion_delay, spec)
                 .ok()?;
-        let base_reward_per_increment =
-            altair::BaseRewardPerIncrement::new(total_active_balance, spec).ok()?;
 
         let fresh_validators_rewards = att
             .indexed
@@ -98,12 +95,7 @@ impl<'a, T: EthSpec> AttMaxCover<'a, T> {
 
                 let mut proposer_reward_numerator = 0;
 
-                // FIXME(sproul): store base_reward in reward cache
-                // let effective_balance = reward_cache.get_effective_balance(index)?;
-                let effective_balance = state.get_effective_balance(index as usize).ok()?;
-                let base_reward =
-                    altair::get_base_reward(effective_balance, base_reward_per_increment, spec)
-                        .ok()?;
+                let base_reward = state.get_base_reward(index as usize).ok()?;
 
                 for (flag_index, weight) in PARTICIPATION_FLAG_WEIGHTS.iter().enumerate() {
                     if att_participation_flags.contains(&flag_index) {