Update beacon-chain/core/transition/transition.go

Co-authored-by: Potuz <potuz@prysmaticlabs.com>

beacon-chain/blockchain/execution_engine.go

@@ -264,7 +264,8 @@ func (s *Service) getPayloadAttribute(ctx context.Context, st state.BeaconState,
 
 	// Get previous randao.
 	st = st.Copy()
-	st, err := transition.ProcessSlotsIfPossible(ctx, st, slot)
+	headRoot := s.headRoot()
+	st, err := transition.ProcessSlotsUsingNextSlotCache(ctx, st, headRoot[:], slot)
 	if err != nil {
 		log.WithError(err).Error("Could not process slots to get payload attribute")
 		return false, emptyAttri, 0

beacon-chain/blockchain/head_sync_committee_info.go

@@ -154,10 +154,14 @@ func (s *Service) getSyncCommitteeHeadState(ctx context.Context, slot primitives
 		if err != nil {
 			return nil, err
 		}
+		headRoot, err := s.HeadRoot(ctx)
+		if err != nil {
+			return nil, err
+		}
 		if headState == nil || headState.IsNil() {
 			return nil, errors.New("nil state")
 		}
-		headState, err = transition.ProcessSlotsIfPossible(ctx, headState, slot)
+		headState, err = transition.ProcessSlotsUsingNextSlotCache(ctx, headState, headRoot, slot)
 		if err != nil {
 			return nil, err
 		}

beacon-chain/blockchain/process_attestation_helpers.go

@@ -42,7 +42,7 @@ func (s *Service) getAttPreState(ctx context.Context, c *ethpb.Checkpoint) (stat
 	if err != nil {
 		return nil, err
 	}
-	baseState, err = transition.ProcessSlotsIfPossible(ctx, baseState, epochStartSlot)
+	baseState, err = transition.ProcessSlotsUsingNextSlotCache(ctx, baseState, c.Root, epochStartSlot)
 	if err != nil {
 		return nil, errors.Wrapf(err, "could not process slots up to epoch %d", c.Epoch)
 	}

beacon-chain/core/transition/transition.go

@@ -156,22 +156,15 @@ func ProcessSlotsUsingNextSlotCache(
 	}
 
 	var err error
-	parentState, err = ProcessSlots(ctx, parentState, slot)
-	if err != nil {
-		return nil, errors.Wrap(err, "could not process slots")
+	if slot > parentState.Slot() {
+		parentState, err = ProcessSlots(ctx, parentState, slot)
+		if err != nil {
+			return nil, errors.Wrap(err, "could not process slots")
+		}
 	}
 	return parentState, nil
 }
 
-// ProcessSlotsIfPossible executes ProcessSlots on the input state when target slot is above the state's slot.
-// Otherwise, it returns the input state unchanged.
-func ProcessSlotsIfPossible(ctx context.Context, state state.BeaconState, targetSlot primitives.Slot) (state.BeaconState, error) {
-	if targetSlot > state.Slot() {
-		return ProcessSlots(ctx, state, targetSlot)
-	}
-	return state, nil
-}
-
 // ProcessSlots process through skip slots and apply epoch transition when it's needed
 //
 // Spec pseudocode definition:

beacon-chain/core/transition/transition_test.go

@@ -643,21 +643,21 @@ func TestProcessSlotsConditionally(t *testing.T) {
 
 	t.Run("target slot below current slot", func(t *testing.T) {
 		require.NoError(t, s.SetSlot(5))
-		s, err := transition.ProcessSlotsIfPossible(ctx, s, 4)
+		s, err := transition.ProcessSlotsUsingNextSlotCache(ctx, s, []byte{}, 4)
 		require.NoError(t, err)
 		assert.Equal(t, primitives.Slot(5), s.Slot())
 	})
 
 	t.Run("target slot equal current slot", func(t *testing.T) {
 		require.NoError(t, s.SetSlot(5))
-		s, err := transition.ProcessSlotsIfPossible(ctx, s, 5)
+		s, err := transition.ProcessSlotsUsingNextSlotCache(ctx, s, []byte{}, 5)
 		require.NoError(t, err)
 		assert.Equal(t, primitives.Slot(5), s.Slot())
 	})
 
 	t.Run("target slot above current slot", func(t *testing.T) {
 		require.NoError(t, s.SetSlot(5))
-		s, err := transition.ProcessSlotsIfPossible(ctx, s, 6)
+		s, err := transition.ProcessSlotsUsingNextSlotCache(ctx, s, []byte{}, 6)
 		require.NoError(t, err)
 		assert.Equal(t, primitives.Slot(6), s.Slot())
 	})

beacon-chain/rpc/eth/beacon/pool.go

@@ -170,7 +170,11 @@ func (bs *Server) SubmitAttesterSlashing(ctx context.Context, req *ethpbv1.Attes
 	if err != nil {
 		return nil, status.Errorf(codes.Internal, "Could not get head state: %v", err)
 	}
-	headState, err = transition.ProcessSlotsIfPossible(ctx, headState, req.Attestation_1.Data.Slot)
+	headRoot, err := bs.ChainInfoFetcher.HeadRoot(ctx)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not get head root: %v", err)
+	}
+	headState, err = transition.ProcessSlotsUsingNextSlotCache(ctx, headState, headRoot, req.Attestation_1.Data.Slot)
 	if err != nil {
 		return nil, status.Errorf(codes.Internal, "Could not process slots: %v", err)
 	}
@@ -226,7 +230,11 @@ func (bs *Server) SubmitProposerSlashing(ctx context.Context, req *ethpbv1.Propo
 	if err != nil {
 		return nil, status.Errorf(codes.Internal, "Could not get head state: %v", err)
 	}
-	headState, err = transition.ProcessSlotsIfPossible(ctx, headState, req.SignedHeader_1.Message.Slot)
+	headRoot, err := bs.ChainInfoFetcher.HeadRoot(ctx)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not get head root: %v", err)
+	}
+	headState, err = transition.ProcessSlotsUsingNextSlotCache(ctx, headState, headRoot, req.SignedHeader_1.Message.Slot)
 	if err != nil {
 		return nil, status.Errorf(codes.Internal, "Could not process slots: %v", err)
 	}
@@ -284,7 +292,11 @@ func (bs *Server) SubmitVoluntaryExit(ctx context.Context, req *ethpbv1.SignedVo
 	if err != nil {
 		return nil, status.Errorf(codes.Internal, "Could not get epoch from message: %v", err)
 	}
-	headState, err = transition.ProcessSlotsIfPossible(ctx, headState, s)
+	headRoot, err := bs.ChainInfoFetcher.HeadRoot(ctx)
+	if err != nil {
+		return nil, status.Errorf(codes.Internal, "Could not get head root: %v", err)
+	}
+	headState, err = transition.ProcessSlotsUsingNextSlotCache(ctx, headState, headRoot, s)
 	if err != nil {
 		return nil, status.Errorf(codes.Internal, "Could not process slots: %v", err)
 	}