core/types: reduce allocations for transaction comparison (#31912)

This PR should reduce overall allocations of a running node by ~10
percent. Since most allocations are coming from the re-heaping of the
transaction pool.

```
(pprof) list EffectiveGasTipCmp
Total: 38197204475
ROUTINE ======================== github.com/ethereum/go-ethereum/core/types.(*Transaction).EffectiveGasTipCmp in github.com/ethereum/go-ethereum/core/types/transaction.go
         0 3766837369 (flat, cum)  9.86% of Total
         .          .    386:func (tx *Transaction) EffectiveGasTipCmp(other *Transaction, baseFee *big.Int) int {
         .          .    387: if baseFee == nil {
         .          .    388:  return tx.GasTipCapCmp(other)
         .          .    389: }
         .          .    390: // Use more efficient internal method.
         .          .    391: txTip, otherTip := new(big.Int), new(big.Int)
         . 1796172553    392: tx.calcEffectiveGasTip(txTip, baseFee)
         . 1970664816    393: other.calcEffectiveGasTip(otherTip, baseFee)
         .          .    394: return txTip.Cmp(otherTip)
         .          .    395:}
         .          .    396:
         .          .    397:// EffectiveGasTipIntCmp compares the effective gasTipCap of a transaction to the given gasTipCap.
         .          .    398:func (tx *Transaction) EffectiveGasTipIntCmp(other *big.Int, baseFee *big.Int) int {
```

This PR reduces the allocations for comparing two transactions from 2 to
0:
```
goos: linux
goarch: amd64
pkg: github.com/ethereum/go-ethereum/core/types
cpu: Intel(R) Core(TM) Ultra 7 155U
                               │ /tmp/old.txt │            /tmp/new.txt             │
                               │    sec/op    │   sec/op     vs base                │
EffectiveGasTipCmp/Original-14    64.67n ± 2%   25.13n ± 9%  -61.13% (p=0.000 n=10)

                               │ /tmp/old.txt │            /tmp/new.txt            │
                               │     B/op     │   B/op     vs base                 │
EffectiveGasTipCmp/Original-14     16.00 ± 0%   0.00 ± 0%  -100.00% (p=0.000 n=10)

                               │ /tmp/old.txt │            /tmp/new.txt             │
                               │  allocs/op   │ allocs/op   vs base                 │
EffectiveGasTipCmp/Original-14     2.000 ± 0%   0.000 ± 0%  -100.00% (p=0.000 n=10)
```

It also speeds up the process by ~60%

There are two minor caveats with this PR:
- We change the API for `EffectiveGasTipCmp` and `EffectiveGasTipIntCmp`
(which are probably not used by much)
- We slightly change the behavior of `tx.EffectiveGasTip` when it
returns an error. It would previously return a negative number on error,
now it does not (since uint256 does not allow for negative numbers)

---------

Signed-off-by: Csaba Kiraly <csaba.kiraly@gmail.com>
Co-authored-by: Csaba Kiraly <csaba.kiraly@gmail.com>

core/txpool/legacypool/legacypool.go

@@ -514,26 +514,15 @@ func (pool *LegacyPool) Pending(filter txpool.PendingFilter) map[common.Address]
 	pool.mu.Lock()
 	defer pool.mu.Unlock()
 
-	// Convert the new uint256.Int types to the old big.Int ones used by the legacy pool
-	var (
-		minTipBig  *big.Int
-		baseFeeBig *big.Int
-	)
-	if filter.MinTip != nil {
-		minTipBig = filter.MinTip.ToBig()
-	}
-	if filter.BaseFee != nil {
-		baseFeeBig = filter.BaseFee.ToBig()
-	}
 	pending := make(map[common.Address][]*txpool.LazyTransaction, len(pool.pending))
 	for addr, list := range pool.pending {
 		txs := list.Flatten()
 
 		// If the miner requests tip enforcement, cap the lists now
-		if minTipBig != nil || filter.GasLimitCap != 0 {
+		if filter.MinTip != nil || filter.GasLimitCap != 0 {
 			for i, tx := range txs {
-				if minTipBig != nil {
+				if filter.MinTip != nil {
-					if tx.EffectiveGasTipIntCmp(minTipBig, baseFeeBig) < 0 {
+					if tx.EffectiveGasTipIntCmp(filter.MinTip, filter.BaseFee) < 0 {
 						txs = txs[:i]
 						break
 					}

core/txpool/legacypool/list.go

@@ -475,7 +475,7 @@ func (l *list) subTotalCost(txs []*types.Transaction) {
 // then the heap is sorted based on the effective tip based on the given base fee.
 // If baseFee is nil then the sorting is based on gasFeeCap.
 type priceHeap struct {
-	baseFee *big.Int // heap should always be re-sorted after baseFee is changed
+	baseFee *uint256.Int // heap should always be re-sorted after baseFee is changed
 	list    []*types.Transaction
 }
 
@@ -677,6 +677,10 @@ func (l *pricedList) Reheap() {
 // SetBaseFee updates the base fee and triggers a re-heap. Note that Removed is not
 // necessary to call right before SetBaseFee when processing a new block.
 func (l *pricedList) SetBaseFee(baseFee *big.Int) {
-	l.urgent.baseFee = baseFee
+	base := new(uint256.Int)
+	if baseFee != nil {
+		base.SetFromBig(baseFee)
+	}
+	l.urgent.baseFee = base
 	l.Reheap()
 }

core/types/transaction.go

@@ -28,6 +28,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/holiman/uint256"
 )
 
 var (
@@ -36,6 +37,7 @@ var (
 	ErrInvalidTxType        = errors.New("transaction type not valid in this context")
 	ErrTxTypeNotSupported   = errors.New("transaction type not supported")
 	ErrGasFeeCapTooLow      = errors.New("fee cap less than base fee")
+	ErrUint256Overflow      = errors.New("bigint overflow, too large for uint256")
 	errShortTypedTx         = errors.New("typed transaction too short")
 	errInvalidYParity       = errors.New("'yParity' field must be 0 or 1")
 	errVYParityMismatch     = errors.New("'v' and 'yParity' fields do not match")
@@ -352,54 +354,66 @@ func (tx *Transaction) GasTipCapIntCmp(other *big.Int) int {
 }
 
 // EffectiveGasTip returns the effective miner gasTipCap for the given base fee.
-// Note: if the effective gasTipCap is negative, this method returns both error
+// Note: if the effective gasTipCap would be negative, this method
-// the actual negative value, _and_ ErrGasFeeCapTooLow
+// returns ErrGasFeeCapTooLow, and value is undefined.
 func (tx *Transaction) EffectiveGasTip(baseFee *big.Int) (*big.Int, error) {
-	dst := new(big.Int)
+	dst := new(uint256.Int)
-	err := tx.calcEffectiveGasTip(dst, baseFee)
+	base := new(uint256.Int)
-	return dst, err
+	if baseFee != nil {
+		if base.SetFromBig(baseFee) {
+			return nil, ErrUint256Overflow
+		}
+	}
+	err := tx.calcEffectiveGasTip(dst, base)
+	return dst.ToBig(), err
 }
 
 // calcEffectiveGasTip calculates the effective gas tip of the transaction and
 // saves the result to dst.
-func (tx *Transaction) calcEffectiveGasTip(dst *big.Int, baseFee *big.Int) error {
+func (tx *Transaction) calcEffectiveGasTip(dst *uint256.Int, baseFee *uint256.Int) error {
 	if baseFee == nil {
-		dst.Set(tx.inner.gasTipCap())
+		if dst.SetFromBig(tx.inner.gasTipCap()) {
+			return ErrUint256Overflow
+		}
 		return nil
 	}
 
 	var err error
-	gasFeeCap := tx.inner.gasFeeCap()
+	if dst.SetFromBig(tx.inner.gasFeeCap()) {
-	if gasFeeCap.Cmp(baseFee) < 0 {
+		return ErrUint256Overflow
+	}
+	if dst.Cmp(baseFee) < 0 {
 		err = ErrGasFeeCapTooLow
 	}
 
-	dst.Sub(gasFeeCap, baseFee)
+	dst.Sub(dst, baseFee)
-	gasTipCap := tx.inner.gasTipCap()
+	gasTipCap := new(uint256.Int)
+	if gasTipCap.SetFromBig(tx.inner.gasTipCap()) {
+		return ErrUint256Overflow
+	}
 	if gasTipCap.Cmp(dst) < 0 {
 		dst.Set(gasTipCap)
 	}
 	return err
 }
 
-// EffectiveGasTipCmp compares the effective gasTipCap of two transactions assuming the given base fee.
+func (tx *Transaction) EffectiveGasTipCmp(other *Transaction, baseFee *uint256.Int) int {
-func (tx *Transaction) EffectiveGasTipCmp(other *Transaction, baseFee *big.Int) int {
 	if baseFee == nil {
 		return tx.GasTipCapCmp(other)
 	}
 	// Use more efficient internal method.
-	txTip, otherTip := new(big.Int), new(big.Int)
+	txTip, otherTip := new(uint256.Int), new(uint256.Int)
 	tx.calcEffectiveGasTip(txTip, baseFee)
 	other.calcEffectiveGasTip(otherTip, baseFee)
 	return txTip.Cmp(otherTip)
 }
 
 // EffectiveGasTipIntCmp compares the effective gasTipCap of a transaction to the given gasTipCap.
-func (tx *Transaction) EffectiveGasTipIntCmp(other *big.Int, baseFee *big.Int) int {
+func (tx *Transaction) EffectiveGasTipIntCmp(other *uint256.Int, baseFee *uint256.Int) int {
 	if baseFee == nil {
-		return tx.GasTipCapIntCmp(other)
+		return tx.GasTipCapIntCmp(other.ToBig())
 	}
-	txTip := new(big.Int)
+	txTip := new(uint256.Int)
 	tx.calcEffectiveGasTip(txTip, baseFee)
 	return txTip.Cmp(other)
 }

core/types/transaction_test.go

@@ -31,6 +31,7 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rlp"
+	"github.com/holiman/uint256"
 )
 
 // The values in those tests are from the Transaction Tests
@@ -609,12 +610,12 @@ func BenchmarkEffectiveGasTip(b *testing.B) {
 		Data:      nil,
 	}
 	tx, _ := SignNewTx(key, signer, txdata)
-	baseFee := big.NewInt(1000000000) // 1 gwei
+	baseFee := uint256.NewInt(1000000000) // 1 gwei
 
 	b.Run("Original", func(b *testing.B) {
 		b.ReportAllocs()
 		for i := 0; i < b.N; i++ {
-			_, err := tx.EffectiveGasTip(baseFee)
+			_, err := tx.EffectiveGasTip(baseFee.ToBig())
 			if err != nil {
 				b.Fatal(err)
 			}
@@ -623,7 +624,7 @@ func BenchmarkEffectiveGasTip(b *testing.B) {
 
 	b.Run("IntoMethod", func(b *testing.B) {
 		b.ReportAllocs()
-		dst := new(big.Int)
+		dst := new(uint256.Int)
 		for i := 0; i < b.N; i++ {
 			err := tx.calcEffectiveGasTip(dst, baseFee)
 			if err != nil {
@@ -634,9 +635,6 @@ func BenchmarkEffectiveGasTip(b *testing.B) {
 }
 
 func TestEffectiveGasTipInto(t *testing.T) {
-	signer := LatestSigner(params.TestChainConfig)
-	key, _ := crypto.GenerateKey()
-
 	testCases := []struct {
 		tipCap  int64
 		feeCap  int64
@@ -652,8 +650,26 @@ func TestEffectiveGasTipInto(t *testing.T) {
 		{tipCap: 50, feeCap: 100, baseFee: nil}, // nil base fee
 	}
 
+	// original, non-allocation golfed version
+	orig := func(tx *Transaction, baseFee *big.Int) (*big.Int, error) {
+		if baseFee == nil {
+			return tx.GasTipCap(), nil
+		}
+		var err error
+		gasFeeCap := tx.GasFeeCap()
+		if gasFeeCap.Cmp(baseFee) < 0 {
+			err = ErrGasFeeCapTooLow
+		}
+		gasFeeCap = gasFeeCap.Sub(gasFeeCap, baseFee)
+		gasTipCap := tx.GasTipCap()
+		if gasTipCap.Cmp(gasFeeCap) < 0 {
+			return gasTipCap, err
+		}
+		return gasFeeCap, err
+	}
+
 	for i, tc := range testCases {
-		txdata := &DynamicFeeTx{
+		tx := NewTx(&DynamicFeeTx{
 			ChainID:   big.NewInt(1),
 			Nonce:     0,
 			GasTipCap: big.NewInt(tc.tipCap),
@@ -662,27 +678,28 @@ func TestEffectiveGasTipInto(t *testing.T) {
 			To:        &common.Address{},
 			Value:     big.NewInt(0),
 			Data:      nil,
-		}
+		})
-		tx, _ := SignNewTx(key, signer, txdata)
 
 		var baseFee *big.Int
+		var baseFee2 *uint256.Int
 		if tc.baseFee != nil {
 			baseFee = big.NewInt(*tc.baseFee)
+			baseFee2 = uint256.NewInt(uint64(*tc.baseFee))
 		}
 
 		// Get result from original method
-		orig, origErr := tx.EffectiveGasTip(baseFee)
+		orig, origErr := orig(tx, baseFee)
 
 		// Get result from new method
-		dst := new(big.Int)
+		dst := new(uint256.Int)
-		newErr := tx.calcEffectiveGasTip(dst, baseFee)
+		newErr := tx.calcEffectiveGasTip(dst, baseFee2)
 
 		// Compare results
 		if (origErr != nil) != (newErr != nil) {
 			t.Fatalf("case %d: error mismatch: orig %v, new %v", i, origErr, newErr)
 		}
 
-		if orig.Cmp(dst) != 0 {
+		if origErr == nil && orig.Cmp(dst.ToBig()) != 0 {
 			t.Fatalf("case %d: result mismatch: orig %v, new %v", i, orig, dst)
 		}
 	}
@@ -692,3 +709,28 @@ func TestEffectiveGasTipInto(t *testing.T) {
 func intPtr(i int64) *int64 {
 	return &i
 }
+
+func BenchmarkEffectiveGasTipCmp(b *testing.B) {
+	signer := LatestSigner(params.TestChainConfig)
+	key, _ := crypto.GenerateKey()
+	txdata := &DynamicFeeTx{
+		ChainID:   big.NewInt(1),
+		Nonce:     0,
+		GasTipCap: big.NewInt(2000000000),
+		GasFeeCap: big.NewInt(3000000000),
+		Gas:       21000,
+		To:        &common.Address{},
+		Value:     big.NewInt(0),
+		Data:      nil,
+	}
+	tx, _ := SignNewTx(key, signer, txdata)
+	other, _ := SignNewTx(key, signer, txdata)
+	baseFee := uint256.NewInt(1000000000) // 1 gwei
+
+	b.Run("Original", func(b *testing.B) {
+		b.ReportAllocs()
+		for i := 0; i < b.N; i++ {
+			tx.EffectiveGasTipCmp(other, baseFee)
+		}
+	})
+}