core/types, trie: reduce allocations in derivesha (#30747)

Alternative to #30746, potential follow-up to #30743 . This PR makes the
stacktrie always copy incoming value buffers, and reuse them internally.

Improvement in #30743:
```
goos: linux
goarch: amd64
pkg: github.com/ethereum/go-ethereum/core/types
cpu: 12th Gen Intel(R) Core(TM) i7-1270P
                          │ derivesha.1 │             derivesha.2              │
                          │   sec/op    │    sec/op     vs base                │
DeriveSha200/stack_trie-8   477.8µ ± 2%   430.0µ ± 12%  -10.00% (p=0.000 n=10)

                          │ derivesha.1  │             derivesha.2              │
                          │     B/op     │     B/op      vs base                │
DeriveSha200/stack_trie-8   45.17Ki ± 0%   25.65Ki ± 0%  -43.21% (p=0.000 n=10)

                          │ derivesha.1 │            derivesha.2             │
                          │  allocs/op  │ allocs/op   vs base                │
DeriveSha200/stack_trie-8   1259.0 ± 0%   232.0 ± 0%  -81.57% (p=0.000 n=10)

```
This PR further enhances that: 

```
goos: linux
goarch: amd64
pkg: github.com/ethereum/go-ethereum/core/types
cpu: 12th Gen Intel(R) Core(TM) i7-1270P
                          │ derivesha.2  │          derivesha.3           │
                          │    sec/op    │    sec/op     vs base          │
DeriveSha200/stack_trie-8   430.0µ ± 12%   423.6µ ± 13%  ~ (p=0.739 n=10)

                          │  derivesha.2  │             derivesha.3              │
                          │     B/op      │     B/op      vs base                │
DeriveSha200/stack_trie-8   25.654Ki ± 0%   4.960Ki ± 0%  -80.67% (p=0.000 n=10)

                          │ derivesha.2 │            derivesha.3             │
                          │  allocs/op  │ allocs/op   vs base                │
DeriveSha200/stack_trie-8   232.00 ± 0%   37.00 ± 0%  -84.05% (p=0.000 n=10)
```
So the total derivesha-improvement over *both PRS* is: 
```
goos: linux
goarch: amd64
pkg: github.com/ethereum/go-ethereum/core/types
cpu: 12th Gen Intel(R) Core(TM) i7-1270P
                          │ derivesha.1 │             derivesha.3              │
                          │   sec/op    │    sec/op     vs base                │
DeriveSha200/stack_trie-8   477.8µ ± 2%   423.6µ ± 13%  -11.33% (p=0.015 n=10)

                          │  derivesha.1  │             derivesha.3              │
                          │     B/op      │     B/op      vs base                │
DeriveSha200/stack_trie-8   45.171Ki ± 0%   4.960Ki ± 0%  -89.02% (p=0.000 n=10)

                          │ derivesha.1  │            derivesha.3             │
                          │  allocs/op   │ allocs/op   vs base                │
DeriveSha200/stack_trie-8   1259.00 ± 0%   37.00 ± 0%  -97.06% (p=0.000 n=10)
```

Since this PR always copies the incoming value, it adds a little bit of
a penalty on the previous insert-benchmark, which copied nothing (always
passed the same empty slice as input) :

```
goos: linux
goarch: amd64
pkg: github.com/ethereum/go-ethereum/trie
cpu: 12th Gen Intel(R) Core(TM) i7-1270P
             │ stacktrie.7  │          stacktrie.10          │
             │    sec/op    │    sec/op     vs base          │
Insert100K-8   88.21m ± 34%   92.37m ± 31%  ~ (p=0.280 n=10)

             │ stacktrie.7  │             stacktrie.10             │
             │     B/op     │     B/op      vs base                │
Insert100K-8   3.424Ki ± 3%   4.581Ki ± 3%  +33.80% (p=0.000 n=10)

             │ stacktrie.7 │            stacktrie.10            │
             │  allocs/op  │ allocs/op   vs base                │
Insert100K-8    22.00 ± 5%   26.00 ± 4%  +18.18% (p=0.000 n=10)
```

---------

Co-authored-by: Gary Rong <[email protected]>
Co-authored-by: Felix Lange <[email protected]>

Author: 3 people

core/types/block.go

@@ -240,7 +240,7 @@ type extblock struct {
 //
 // The receipt's bloom must already calculated for the block's bloom to be
 // correctly calculated.
-func NewBlock(header *Header, body *Body, receipts []*Receipt, hasher TrieHasher) *Block {
+func NewBlock(header *Header, body *Body, receipts []*Receipt, hasher ListHasher) *Block {
 	if body == nil {
 		body = &Body{}
 	}

core/types/hashing.go

@@ -27,7 +27,7 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
-// hasherPool holds LegacyKeccak256 hashers for rlpHash.
+// hasherPool holds LegacyKeccak256 buffer for rlpHash.
 var hasherPool = sync.Pool{
 	New: func() interface{} { return crypto.NewKeccakState() },
 }
@@ -75,11 +75,17 @@ func prefixedRlpHash(prefix byte, x interface{}) (h common.Hash) {
 	return h
 }
 
-// TrieHasher is the tool used to calculate the hash of derivable list.
-// This is internal, do not use.
-type TrieHasher interface {
+// ListHasher defines the interface for computing the hash of a derivable list.
+type ListHasher interface {
+	// Reset clears the internal state of the hasher, preparing it for reuse.
 	Reset()
-	Update([]byte, []byte) error
+
+	// Update inserts the given key-value pair into the hasher.
+	// The implementation must copy the provided slices, allowing the caller
+	// to safely modify them after the call returns.
+	Update(key []byte, value []byte) error
+
+	// Hash computes and returns the final hash of all inserted key-value pairs.
 	Hash() common.Hash
 }
 
@@ -91,19 +97,20 @@ type DerivableList interface {
 	EncodeIndex(int, *bytes.Buffer)
 }
 
+// encodeForDerive encodes the element in the list at the position i into the buffer.
 func encodeForDerive(list DerivableList, i int, buf *bytes.Buffer) []byte {
 	buf.Reset()
 	list.EncodeIndex(i, buf)
-	// It's really unfortunate that we need to perform this copy.
-	// StackTrie holds onto the values until Hash is called, so the values
-	// written to it must not alias.
-	return common.CopyBytes(buf.Bytes())
+	return buf.Bytes()
 }
 
 // DeriveSha creates the tree hashes of transactions, receipts, and withdrawals in a block header.
-func DeriveSha(list DerivableList, hasher TrieHasher) common.Hash {
+func DeriveSha(list DerivableList, hasher ListHasher) common.Hash {
 	hasher.Reset()
 
+	// Allocate a buffer for value encoding. As the hasher is claimed that all
+	// supplied key value pairs will be copied by hasher and safe to reuse the
+	// encoding buffer.
 	valueBuf := encodeBufferPool.Get().(*bytes.Buffer)
 	defer encodeBufferPool.Put(valueBuf)
 

core/types/hashing_test.go

@@ -26,12 +26,10 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
-	"github.com/ethereum/go-ethereum/core/rawdb"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/trie"
-	"github.com/ethereum/go-ethereum/triedb"
 )
 
 func TestDeriveSha(t *testing.T) {
@@ -40,7 +38,7 @@ func TestDeriveSha(t *testing.T) {
 		t.Fatal(err)
 	}
 	for len(txs) < 1000 {
-		exp := types.DeriveSha(txs, trie.NewEmpty(triedb.NewDatabase(rawdb.NewMemoryDatabase(), nil)))
+		exp := types.DeriveSha(txs, trie.NewListHasher())
 		got := types.DeriveSha(txs, trie.NewStackTrie(nil))
 		if !bytes.Equal(got[:], exp[:]) {
 			t.Fatalf("%d txs: got %x exp %x", len(txs), got, exp)
@@ -76,38 +74,53 @@ func TestEIP2718DeriveSha(t *testing.T) {
 	}
 }
 
+// goos: darwin
+// goarch: arm64
+// pkg: github.com/ethereum/go-ethereum/core/types
+// cpu: Apple M1 Pro
+// BenchmarkDeriveSha200
+// BenchmarkDeriveSha200/std_trie
+// BenchmarkDeriveSha200/std_trie-8         	    6754	    174074 ns/op	   80054 B/op	    1926 allocs/op
+// BenchmarkDeriveSha200/stack_trie
+// BenchmarkDeriveSha200/stack_trie-8       	    7296	    162675 ns/op	     745 B/op	      19 allocs/op
 func BenchmarkDeriveSha200(b *testing.B) {
 	txs, err := genTxs(200)
 	if err != nil {
 		b.Fatal(err)
 	}
-	var exp common.Hash
-	var got common.Hash
+	want := types.DeriveSha(txs, trie.NewListHasher())
+
 	b.Run("std_trie", func(b *testing.B) {
 		b.ReportAllocs()
+		var have common.Hash
 		for b.Loop() {
-			exp = types.DeriveSha(txs, trie.NewEmpty(triedb.NewDatabase(rawdb.NewMemoryDatabase(), nil)))
+			have = types.DeriveSha(txs, trie.NewListHasher())
+		}
+		if have != want {
+			b.Errorf("have %x want %x", have, want)
 		}
 	})
 
+	st := trie.NewStackTrie(nil)
 	b.Run("stack_trie", func(b *testing.B) {
-		b.ResetTimer()
 		b.ReportAllocs()
+		var have common.Hash
 		for b.Loop() {
-			got = types.DeriveSha(txs, trie.NewStackTrie(nil))
+			st.Reset()
+			have = types.DeriveSha(txs, st)
+		}
+		if have != want {
+			b.Errorf("have %x want %x", have, want)
 		}
 	})
-	if got != exp {
-		b.Errorf("got %x exp %x", got, exp)
-	}
 }
 
 func TestFuzzDeriveSha(t *testing.T) {
 	// increase this for longer runs -- it's set to quite low for travis
 	rndSeed := mrand.Int()
 	for i := 0; i < 10; i++ {
 		seed := rndSeed + i
-		exp := types.DeriveSha(newDummy(i), trie.NewEmpty(triedb.NewDatabase(rawdb.NewMemoryDatabase(), nil)))
+		exp := types.DeriveSha(newDummy(i), trie.NewListHasher())
 		got := types.DeriveSha(newDummy(i), trie.NewStackTrie(nil))
 		if !bytes.Equal(got[:], exp[:]) {
 			printList(t, newDummy(seed))
@@ -135,7 +148,7 @@ func TestDerivableList(t *testing.T) {
 		},
 	}
 	for i, tc := range tcs[1:] {
-		exp := types.DeriveSha(flatList(tc), trie.NewEmpty(triedb.NewDatabase(rawdb.NewMemoryDatabase(), nil)))
+		exp := types.DeriveSha(flatList(tc), trie.NewListHasher())
 		got := types.DeriveSha(flatList(tc), trie.NewStackTrie(nil))
 		if !bytes.Equal(got[:], exp[:]) {
 			t.Fatalf("case %d: got %x exp %x", i, got, exp)

internal/blocktest/test_hash.go

@@ -23,6 +23,7 @@
 package blocktest
 
 import (
+	"bytes"
 	"hash"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -48,8 +49,8 @@ func (h *testHasher) Reset() {
 
 // Update updates the hash state with the given key and value.
 func (h *testHasher) Update(key, val []byte) error {
-	h.hasher.Write(key)
-	h.hasher.Write(val)
+	h.hasher.Write(bytes.Clone(key))
+	h.hasher.Write(bytes.Clone(val))
 	return nil
 }
 

trie/bytepool.go

@@ -32,8 +32,8 @@ func newBytesPool(sliceCap, nitems int) *bytesPool {
 	}
 }
 
-// Get returns a slice. Safe for concurrent use.
-func (bp *bytesPool) Get() []byte {
+// get returns a slice. Safe for concurrent use.
+func (bp *bytesPool) get() []byte {
 	select {
 	case b := <-bp.c:
 		return b
@@ -42,18 +42,18 @@ func (bp *bytesPool) Get() []byte {
 	}
 }
 
-// GetWithSize returns a slice with specified byte slice size.
-func (bp *bytesPool) GetWithSize(s int) []byte {
-	b := bp.Get()
+// getWithSize returns a slice with specified byte slice size.
+func (bp *bytesPool) getWithSize(s int) []byte {
+	b := bp.get()
 	if cap(b) < s {
 		return make([]byte, s)
 	}
 	return b[:s]
 }
 
-// Put returns a slice to the pool. Safe for concurrent use. This method
+// put returns a slice to the pool. Safe for concurrent use. This method
 // will ignore slices that are too small or too large (>3x the cap)
-func (bp *bytesPool) Put(b []byte) {
+func (bp *bytesPool) put(b []byte) {
 	if c := cap(b); c < bp.w || c > 3*bp.w {
 		return
 	}
@@ -62,3 +62,40 @@ func (bp *bytesPool) Put(b []byte) {
 	default:
 	}
 }
+
+// unsafeBytesPool is a pool for byte slices. It is not safe for concurrent use.
+type unsafeBytesPool struct {
+	items [][]byte
+	w     int
+}
+
+// newUnsafeBytesPool creates a new unsafeBytesPool. The sliceCap sets the
+// capacity of newly allocated slices, and the nitems determines how many
+// items the pool will hold, at maximum.
+func newUnsafeBytesPool(sliceCap, nitems int) *unsafeBytesPool {
+	return &unsafeBytesPool{
+		items: make([][]byte, 0, nitems),
+		w:     sliceCap,
+	}
+}
+
+// Get returns a slice with pre-allocated space.
+func (bp *unsafeBytesPool) get() []byte {
+	if len(bp.items) > 0 {
+		last := bp.items[len(bp.items)-1]
+		bp.items = bp.items[:len(bp.items)-1]
+		return last
+	}
+	return make([]byte, 0, bp.w)
+}
+
+// put returns a slice to the pool. This method will ignore slices that are
+// too small or too large (>3x the cap)
+func (bp *unsafeBytesPool) put(b []byte) {
+	if c := cap(b); c < bp.w || c > 3*bp.w {
+		return
+	}
+	if len(bp.items) < cap(bp.items) {
+		bp.items = append(bp.items, b)
+	}
+}

trie/list_hasher.go

@@ -0,0 +1,56 @@
+// Copyright 2025 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package trie
+
+import (
+	"bytes"
+
+	"github.com/ethereum/go-ethereum/common"
+)
+
+// ListHasher is a wrapper of the Merkle-Patricia-Trie, which implements
+// types.ListHasher. Compared to a Trie instance, the Update method of this
+// type always deep-copies its input slices.
+//
+// This implementation is very inefficient in terms of memory allocation,
+// compared with StackTrie. It exists only for correctness comparison purposes.
+type ListHasher struct {
+	tr *Trie
+}
+
+// NewListHasher initializes the list hasher.
+func NewListHasher() *ListHasher {
+	return &ListHasher{
+		tr: NewEmpty(nil),
+	}
+}
+
+// Reset clears the internal state prepares the ListHasher for reuse.
+func (h *ListHasher) Reset() {
+	h.tr.reset()
+}
+
+// Update inserts a key-value pair into the trie.
+func (h *ListHasher) Update(key []byte, value []byte) error {
+	key, value = bytes.Clone(key), bytes.Clone(value)
+	return h.tr.Update(key, value)
+}
+
+// Hash computes the root hash of all inserted key-value pairs.
+func (h *ListHasher) Hash() common.Hash {
+	return h.tr.Hash()
+}