refactor: remove some reallocations from decoder (#126)

Co-authored-by: Vladimir Trifonov <trifonov.vp@gmail.com>
0xPolygonZero · Mar 26, 2024 · cab64b4 · cab64b4
1 parent 71cd5b5
commit cab64b4
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Showing 2 changed files with 12 additions and 28 deletions.
diff --git a/trace_decoder/src/compact/compact_prestate_processing.rs b/trace_decoder/src/compact/compact_prestate_processing.rs
@@ -403,10 +403,6 @@ impl ParserState {
     ) -> CompactParsingResult<usize> {
         traverser.get_next_n_elems_into_buf(MAX_WITNESS_ENTRIES_NEEDED_TO_MATCH_A_RULE, buf);
 
-        // TODO: There is a decent amount of code duplication with the matches and the
-        // calls to `invalid_witness_err`. We should condense this...
-
-        // TODO: These clones are really bad, but we will clean this up once it works.
         match buf[0].clone() {
             WitnessEntry::Instruction(Instruction::EmptyRoot) => {
                 Self::traverser_replace_prev_n_nodes_entry_helper(1, traverser, NodeEntry::Empty)
@@ -418,13 +414,13 @@ impl ParserState {
                 Self::traverser_replace_prev_n_nodes_entry_helper(
                     1,
                     traverser,
-                    NodeEntry::Leaf(k, LeafNodeData::Value(v.clone().into())),
+                    NodeEntry::Leaf(k, LeafNodeData::Value(v.into())),
                 )
             }
             WitnessEntry::Instruction(Instruction::Extension(k)) => {
                 traverser.get_prev_n_elems_into_buf(1, buf);
 
-                match buf[0].clone() {
+                match &buf[0] {
                     WitnessEntry::Node(node) => Self::traverser_replace_prev_n_nodes_entry_helper(
                         2,
                         traverser,
@@ -434,11 +430,7 @@ impl ParserState {
                 }
             }
             WitnessEntry::Instruction(Instruction::Code(c)) => {
-                Self::traverser_replace_prev_n_nodes_entry_helper(
-                    1,
-                    traverser,
-                    NodeEntry::Code(c.clone()),
-                )
+                Self::traverser_replace_prev_n_nodes_entry_helper(1, traverser, NodeEntry::Code(c))
             }
             WitnessEntry::Instruction(Instruction::AccountLeaf(k, n, b, has_code, has_storage)) => {
                 let (n_nodes_to_replace, account_node_code, s_trie) = match (has_code, has_storage)

diff --git a/trace_decoder/src/decoding.rs b/trace_decoder/src/decoding.rs
@@ -511,26 +511,18 @@ impl ProcessedBlockTrace {
         withdrawals: Vec<(Address, U256)>,
         dummies_already_added: bool,
     ) -> TraceParsingResult<()> {
-        let withdrawals_with_hashed_addrs_iter = withdrawals
-            .iter()
-            .map(|(addr, v)| (*addr, hash(addr.as_bytes()), *v));
+        let withdrawals_with_hashed_addrs_iter = || {
+            withdrawals
+                .iter()
+                .map(|(addr, v)| (*addr, hash(addr.as_bytes()), *v))
+        };
 
         match dummies_already_added {
             // If we have no actual dummy proofs, then we create one and append it to the
             // end of the block.
             false => {
-                // TODO: Decide if we want this allocation...
-                // To avoid double hashing the addrs, but I don't know if the extra `Vec`
-                // allocation is worth it.
-                let withdrawals_with_hashed_addrs: Vec<_> =
-                    withdrawals_with_hashed_addrs_iter.collect();
-
-                // Dummy state will be the state after the final txn. Also need to include the
-                // account nodes that were accessed by the withdrawals.
-                let withdrawal_addrs = withdrawals_with_hashed_addrs
-                    .iter()
-                    .cloned()
-                    .map(|(_, h_addr, _)| h_addr);
+                let withdrawal_addrs =
+                    withdrawals_with_hashed_addrs_iter().map(|(_, h_addr, _)| h_addr);
                 let mut withdrawal_dummy = create_dummy_gen_input_with_state_addrs_accessed(
                     other_data,
                     extra_data,
@@ -539,7 +531,7 @@ impl ProcessedBlockTrace {
                 )?;
 
                 Self::update_trie_state_from_withdrawals(
-                    withdrawals_with_hashed_addrs,
+                    withdrawals_with_hashed_addrs_iter(),
                     &mut final_trie_state.state,
                 )?;
 
@@ -552,7 +544,7 @@ impl ProcessedBlockTrace {
             }
             true => {
                 Self::update_trie_state_from_withdrawals(
-                    withdrawals_with_hashed_addrs_iter,
+                    withdrawals_with_hashed_addrs_iter(),
                     &mut final_trie_state.state,
                 )?;