core: use slices package for sorting (#27489)

Co-authored-by: Felix Lange <fjl@twurst.com>

Author: Dan Laine

core/blockchain.go

@@ -23,7 +23,6 @@ import (
 	"io"
 	"math/big"
 	"runtime"
-	"sort"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -48,6 +47,7 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/trie"
+	"golang.org/x/exp/slices"
 )
 
 var (
@@ -1015,8 +1015,8 @@ func (bc *BlockChain) procFutureBlocks() {
 		}
 	}
 	if len(blocks) > 0 {
-		sort.Slice(blocks, func(i, j int) bool {
-			return blocks[i].NumberU64() < blocks[j].NumberU64()
+		slices.SortFunc(blocks, func(a, b *types.Block) bool {
+			return a.NumberU64() < b.NumberU64()
 		})
 		// Insert one by one as chain insertion needs contiguous ancestry between blocks
 		for i := range blocks {

core/forkid/forkid.go

@@ -24,13 +24,13 @@ import (
 	"math"
 	"math/big"
 	"reflect"
-	"sort"
 	"strings"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/params"
+	"golang.org/x/exp/slices"
 )
 
 var (
@@ -270,8 +270,8 @@ func gatherForks(config *params.ChainConfig) ([]uint64, []uint64) {
 			}
 		}
 	}
-	sort.Slice(forksByBlock, func(i, j int) bool { return forksByBlock[i] < forksByBlock[j] })
-	sort.Slice(forksByTime, func(i, j int) bool { return forksByTime[i] < forksByTime[j] })
+	slices.Sort(forksByBlock)
+	slices.Sort(forksByTime)
 
 	// Deduplicate fork identifiers applying multiple forks
 	for i := 1; i < len(forksByBlock); i++ {

core/mkalloc.go

@@ -30,32 +30,28 @@ import (
 	"fmt"
 	"math/big"
 	"os"
-	"sort"
 	"strconv"
 
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/rlp"
+	"golang.org/x/exp/slices"
 )
 
 type allocItem struct{ Addr, Balance *big.Int }
 
-type allocList []allocItem
-
-func (a allocList) Len() int           { return len(a) }
-func (a allocList) Less(i, j int) bool { return a[i].Addr.Cmp(a[j].Addr) < 0 }
-func (a allocList) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
-
-func makelist(g *core.Genesis) allocList {
-	a := make(allocList, 0, len(g.Alloc))
+func makelist(g *core.Genesis) []allocItem {
+	items := make([]allocItem, 0, len(g.Alloc))
 	for addr, account := range g.Alloc {
 		if len(account.Storage) > 0 || len(account.Code) > 0 || account.Nonce != 0 {
 			panic(fmt.Sprintf("can't encode account %x", addr))
 		}
 		bigAddr := new(big.Int).SetBytes(addr.Bytes())
-		a = append(a, allocItem{bigAddr, account.Balance})
+		items = append(items, allocItem{bigAddr, account.Balance})
 	}
-	sort.Sort(a)
-	return a
+	slices.SortFunc(items, func(a, b allocItem) bool {
+		return a.Addr.Cmp(b.Addr) < 0
+	})
+	return items
 }
 
 func makealloc(g *core.Genesis) string {

core/rawdb/accessors_chain.go

@@ -22,7 +22,6 @@ import (
 	"errors"
 	"fmt"
 	"math/big"
-	"sort"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
@@ -31,6 +30,7 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/ethereum/go-ethereum/rlp"
+	"golang.org/x/exp/slices"
 )
 
 // ReadCanonicalHash retrieves the hash assigned to a canonical block number.
@@ -836,23 +836,13 @@ type badBlock struct {
 	Body   *types.Body
 }
 
-// badBlockList implements the sort interface to allow sorting a list of
-// bad blocks by their number in the reverse order.
-type badBlockList []*badBlock
-
-func (s badBlockList) Len() int { return len(s) }
-func (s badBlockList) Less(i, j int) bool {
-	return s[i].Header.Number.Uint64() < s[j].Header.Number.Uint64()
-}
-func (s badBlockList) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
-
 // ReadBadBlock retrieves the bad block with the corresponding block hash.
 func ReadBadBlock(db ethdb.Reader, hash common.Hash) *types.Block {
 	blob, err := db.Get(badBlockKey)
 	if err != nil {
 		return nil
 	}
-	var badBlocks badBlockList
+	var badBlocks []*badBlock
 	if err := rlp.DecodeBytes(blob, &badBlocks); err != nil {
 		return nil
 	}
@@ -871,7 +861,7 @@ func ReadAllBadBlocks(db ethdb.Reader) []*types.Block {
 	if err != nil {
 		return nil
 	}
-	var badBlocks badBlockList
+	var badBlocks []*badBlock
 	if err := rlp.DecodeBytes(blob, &badBlocks); err != nil {
 		return nil
 	}
@@ -889,7 +879,7 @@ func WriteBadBlock(db ethdb.KeyValueStore, block *types.Block) {
 	if err != nil {
 		log.Warn("Failed to load old bad blocks", "error", err)
 	}
-	var badBlocks badBlockList
+	var badBlocks []*badBlock
 	if len(blob) > 0 {
 		if err := rlp.DecodeBytes(blob, &badBlocks); err != nil {
 			log.Crit("Failed to decode old bad blocks", "error", err)
@@ -905,7 +895,10 @@ func WriteBadBlock(db ethdb.KeyValueStore, block *types.Block) {
 		Header: block.Header(),
 		Body:   block.Body(),
 	})
-	sort.Sort(sort.Reverse(badBlocks))
+	slices.SortFunc(badBlocks, func(a, b *badBlock) bool {
+		// Note: sorting in descending number order.
+		return a.Header.Number.Uint64() >= b.Header.Number.Uint64()
+	})
 	if len(badBlocks) > badBlockToKeep {
 		badBlocks = badBlocks[:badBlockToKeep]
 	}

core/rawdb/chain_iterator_test.go

@@ -19,12 +19,12 @@ package rawdb
 import (
 	"math/big"
 	"reflect"
-	"sort"
 	"sync"
 	"testing"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
+	"golang.org/x/exp/slices"
 )
 
 func TestChainIterator(t *testing.T) {
@@ -92,9 +92,11 @@ func TestChainIterator(t *testing.T) {
 			}
 		}
 		if !c.reverse {
-			sort.Ints(numbers)
+			slices.Sort(numbers)
 		} else {
-			sort.Sort(sort.Reverse(sort.IntSlice(numbers)))
+			slices.SortFunc(numbers, func(a, b int) bool {
+				return a > b // Sort descending
+			})
 		}
 		if !reflect.DeepEqual(numbers, c.expect) {
 			t.Fatalf("Case %d failed, visit element mismatch, want %v, got %v", i, c.expect, numbers)

core/state/snapshot/difflayer.go

@@ -21,7 +21,6 @@ import (
 	"fmt"
 	"math"
 	"math/rand"
-	"sort"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -30,6 +29,7 @@ import (
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/rlp"
 	bloomfilter "github.com/holiman/bloomfilter/v2"
+	"golang.org/x/exp/slices"
 )
 
 var (
@@ -525,7 +525,7 @@ func (dl *diffLayer) AccountList() []common.Hash {
 			dl.accountList = append(dl.accountList, hash)
 		}
 	}
-	sort.Sort(hashes(dl.accountList))
+	slices.SortFunc(dl.accountList, common.Hash.Less)
 	dl.memory += uint64(len(dl.accountList) * common.HashLength)
 	return dl.accountList
 }
@@ -563,7 +563,7 @@ func (dl *diffLayer) StorageList(accountHash common.Hash) ([]common.Hash, bool)
 	for k := range storageMap {
 		storageList = append(storageList, k)
 	}
-	sort.Sort(hashes(storageList))
+	slices.SortFunc(storageList, common.Hash.Less)
 	dl.storageList[accountHash] = storageList
 	dl.memory += uint64(len(dl.storageList)*common.HashLength + common.HashLength)
 	return storageList, destructed

core/state/snapshot/iterator_fast.go

@@ -22,6 +22,7 @@ import (
 	"sort"
 
 	"github.com/ethereum/go-ethereum/common"
+	"golang.org/x/exp/slices"
 )
 
 // weightedIterator is a iterator with an assigned weight. It is used to prioritise
@@ -32,18 +33,10 @@ type weightedIterator struct {
 	priority int
 }
 
-// weightedIterators is a set of iterators implementing the sort.Interface.
-type weightedIterators []*weightedIterator
-
-// Len implements sort.Interface, returning the number of active iterators.
-func (its weightedIterators) Len() int { return len(its) }
-
-// Less implements sort.Interface, returning which of two iterators in the stack
-// is before the other.
-func (its weightedIterators) Less(i, j int) bool {
+func (it *weightedIterator) Less(other *weightedIterator) bool {
 	// Order the iterators primarily by the account hashes
-	hashI := its[i].it.Hash()
-	hashJ := its[j].it.Hash()
+	hashI := it.it.Hash()
+	hashJ := other.it.Hash()
 
 	switch bytes.Compare(hashI[:], hashJ[:]) {
 	case -1:
@@ -52,12 +45,7 @@ func (its weightedIterators) Less(i, j int) bool {
 		return false
 	}
 	// Same account/storage-slot in multiple layers, split by priority
-	return its[i].priority < its[j].priority
-}
-
-// Swap implements sort.Interface, swapping two entries in the iterator stack.
-func (its weightedIterators) Swap(i, j int) {
-	its[i], its[j] = its[j], its[i]
+	return it.priority < other.priority
 }
 
 // fastIterator is a more optimized multi-layer iterator which maintains a
@@ -69,7 +57,7 @@ type fastIterator struct {
 	curAccount []byte
 	curSlot    []byte
 
-	iterators weightedIterators
+	iterators []*weightedIterator
 	initiated bool
 	account   bool
 	fail      error
@@ -167,7 +155,9 @@ func (fi *fastIterator) init() {
 		}
 	}
 	// Re-sort the entire list
-	sort.Sort(fi.iterators)
+	slices.SortFunc(fi.iterators, func(a, b *weightedIterator) bool {
+		return a.Less(b)
+	})
 	fi.initiated = false
 }