identify: use zero-alloc slice sorting function (#2396)

p2p/protocol/identify/id.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"sort"
 	"sync"
 	"time"
 
@@ -557,9 +556,9 @@ func readAllIDMessages(r pbio.Reader, finalMsg proto.Message) error {
 
 func (ids *idService) updateSnapshot() (updated bool) {
 	addrs := ids.Host.Addrs()
-	sort.Slice(addrs, func(i, j int) bool { return bytes.Compare(addrs[i].Bytes(), addrs[j].Bytes()) == -1 })
+	slices.SortFunc(addrs, func(a, b ma.Multiaddr) bool { return bytes.Compare(a.Bytes(), b.Bytes()) == -1 })
 	protos := ids.Host.Mux().Protocols()
-	sort.Slice(protos, func(i, j int) bool { return protos[i] < protos[j] })
+	slices.Sort(protos)
 	snapshot := identifySnapshot{
 		addrs:     addrs,
 		protocols: protos,

p2p/protocol/identify/obsaddr.go

@@ -3,10 +3,11 @@ package identify
 import (
 	"context"
 	"fmt"
-	"sort"
 	"sync"
 	"time"
 
+	"golang.org/x/exp/slices"
+
 	"github.com/libp2p/go-libp2p/core/event"
 	"github.com/libp2p/go-libp2p/core/host"
 	"github.com/libp2p/go-libp2p/core/network"
@@ -213,14 +214,10 @@ func (oas *ObservedAddrManager) filter(observedAddrs []*observedAddr) []ma.Multi
 
 		// We prefer inbound connection observations over outbound.
 		// For ties, we prefer the ones with more votes.
-		sort.Slice(s, func(i int, j int) bool {
-			first := s[i]
-			second := s[j]
-
+		slices.SortFunc(s, func(first, second *observedAddr) bool {
 			if first.numInbound > second.numInbound {
 				return true
 			}
-
 			return len(first.seenBy) > len(second.seenBy)
 		})