diff --git a/benchmarks/bench_test.go b/benchmarks/bench_test.go
new file mode 100644
index 0000000..db85546
--- /dev/null
+++ b/benchmarks/bench_test.go
@@ -0,0 +1,521 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Large data benchmark.
+// The JSON data is a summary of agl's changes in the
+// go, webkit, and chromium open source projects.
+// We benchmark converting between the JSON form
+// and in-memory data structures.
+
+package benchmark
+
+import (
+	"bytes"
+	"compress/gzip"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strings"
+	"testing"
+
+	stdjson "encoding/json"
+
+	"github.com/goccy/go-json"
+	jsoniter "github.com/json-iterator/go"
+)
+
+type codeResponse struct {
+	Tree     *codeNode `json:"tree"`
+	Username string    `json:"username"`
+}
+
+type codeNode struct {
+	Name     string      `json:"name"`
+	Kids     []*codeNode `json:"kids"`
+	CLWeight float64     `json:"cl_weight"`
+	Touches  int         `json:"touches"`
+	MinT     int64       `json:"min_t"`
+	MaxT     int64       `json:"max_t"`
+	MeanT    int64       `json:"mean_t"`
+}
+
+var codeJSON []byte
+var codeStruct codeResponse
+
+func codeInit() {
+	f, err := os.Open("testdata/code.json.gz")
+	if err != nil {
+		panic(err)
+	}
+	defer f.Close()
+	gz, err := gzip.NewReader(f)
+	if err != nil {
+		panic(err)
+	}
+	data, err := ioutil.ReadAll(gz)
+	if err != nil {
+		panic(err)
+	}
+
+	codeJSON = data
+
+	if err := stdjson.Unmarshal(codeJSON, &codeStruct); err != nil {
+		panic("unmarshal code.json: " + err.Error())
+	}
+	{
+		stdjsonbytes, err := stdjson.Marshal(&codeStruct)
+		if err != nil {
+			panic("marshal code.json: " + err.Error())
+		}
+		jsonbytes, err := json.Marshal(&codeStruct)
+		if err != nil {
+			panic("marshal code.json: " + err.Error())
+		}
+		if len(stdjsonbytes) != len(jsonbytes) {
+			panic(fmt.Sprintf("stdjson = %d but go-json = %d", len(stdjsonbytes), len(jsonbytes)))
+		}
+	}
+	if _, err := json.Marshal(&codeStruct); err != nil {
+		panic("marshal code.json: " + err.Error())
+	}
+	if !bytes.Equal(data, codeJSON) {
+		println("different lengths", len(data), len(codeJSON))
+		for i := 0; i < len(data) && i < len(codeJSON); i++ {
+			if data[i] != codeJSON[i] {
+				println("re-marshal: changed at byte", i)
+				println("orig: ", string(codeJSON[i-10:i+10]))
+				println("new: ", string(data[i-10:i+10]))
+				break
+			}
+		}
+		panic("re-marshal code.json: different result")
+	}
+}
+
+func Benchmark_EncodeBigData_EncodingJson(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		enc := stdjson.NewEncoder(ioutil.Discard)
+		for pb.Next() {
+			if err := enc.Encode(&codeStruct); err != nil {
+				b.Fatal("Encode:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func Benchmark_EncodeBigData_JsonIter(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	var json = jsoniter.ConfigCompatibleWithStandardLibrary
+	b.RunParallel(func(pb *testing.PB) {
+		enc := json.NewEncoder(ioutil.Discard)
+		for pb.Next() {
+			if err := enc.Encode(&codeStruct); err != nil {
+				b.Fatal("Encode:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func Benchmark_EncodeBigData_GoJson(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		enc := json.NewEncoder(ioutil.Discard)
+		for pb.Next() {
+			if err := enc.Encode(&codeStruct); err != nil {
+				b.Fatal("Encode:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func Benchmark_MarshalBigData_EncodingJson(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			if _, err := stdjson.Marshal(&codeStruct); err != nil {
+				b.Fatal("Marshal:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func Benchmark_MarshalBigData_JsonIter(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	var json = jsoniter.ConfigCompatibleWithStandardLibrary
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			if _, err := json.Marshal(&codeStruct); err != nil {
+				b.Fatal("Marshal:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func Benchmark_MarshalBigData_GoJson(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			if _, err := json.Marshal(&codeStruct); err != nil {
+				b.Fatal("Marshal:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func benchMarshalBytes(n int, marshaler func(interface{}) ([]byte, error)) func(*testing.B) {
+	sample := []byte("hello world")
+	// Use a struct pointer, to avoid an allocation when passing it as an
+	// interface parameter to Marshal.
+	v := &struct {
+		Bytes []byte
+	}{
+		bytes.Repeat(sample, (n/len(sample))+1)[:n],
+	}
+	return func(b *testing.B) {
+		b.ReportAllocs()
+		for i := 0; i < b.N; i++ {
+			if _, err := marshaler(v); err != nil {
+				b.Fatal("Marshal:", err)
+			}
+		}
+	}
+}
+
+func Benchmark_MarshalBytes_EncodingJson(b *testing.B) {
+	// 32 fits within encodeState.scratch.
+	b.Run("32", benchMarshalBytes(32, stdjson.Marshal))
+	// 256 doesn't fit in encodeState.scratch, but is small enough to
+	// allocate and avoid the slower base64.NewEncoder.
+	b.Run("256", benchMarshalBytes(256, stdjson.Marshal))
+	// 4096 is large enough that we want to avoid allocating for it.
+	b.Run("4096", benchMarshalBytes(4096, stdjson.Marshal))
+}
+
+func Benchmark_MarshalBytes_JsonIter(b *testing.B) {
+	var json = jsoniter.ConfigCompatibleWithStandardLibrary
+	// 32 fits within encodeState.scratch.
+	b.Run("32", benchMarshalBytes(32, json.Marshal))
+	// 256 doesn't fit in encodeState.scratch, but is small enough to
+	// allocate and avoid the slower base64.NewEncoder.
+	b.Run("256", benchMarshalBytes(256, json.Marshal))
+	// 4096 is large enough that we want to avoid allocating for it.
+	b.Run("4096", benchMarshalBytes(4096, json.Marshal))
+}
+
+func Benchmark_MarshalBytes_GoJson(b *testing.B) {
+	b.ReportAllocs()
+	// 32 fits within encodeState.scratch.
+	b.Run("32", benchMarshalBytes(32, json.Marshal))
+	// 256 doesn't fit in encodeState.scratch, but is small enough to
+	// allocate and avoid the slower base64.NewEncoder.
+	b.Run("256", benchMarshalBytes(256, json.Marshal))
+	// 4096 is large enough that we want to avoid allocating for it.
+	b.Run("4096", benchMarshalBytes(4096, json.Marshal))
+}
+
+func Benchmark_EncodeRawMessage_EncodingJson(b *testing.B) {
+	b.ReportAllocs()
+
+	m := struct {
+		A int
+		B json.RawMessage
+	}{}
+
+	b.RunParallel(func(pb *testing.PB) {
+		enc := stdjson.NewEncoder(ioutil.Discard)
+		for pb.Next() {
+			if err := enc.Encode(&m); err != nil {
+				b.Fatal("Encode:", err)
+			}
+		}
+	})
+}
+
+func Benchmark_EncodeRawMessage_JsonIter(b *testing.B) {
+	b.ReportAllocs()
+
+	m := struct {
+		A int
+		B json.RawMessage
+	}{}
+
+	var json = jsoniter.ConfigCompatibleWithStandardLibrary
+
+	b.RunParallel(func(pb *testing.PB) {
+		enc := json.NewEncoder(ioutil.Discard)
+		for pb.Next() {
+			if err := enc.Encode(&m); err != nil {
+				b.Fatal("Encode:", err)
+			}
+		}
+	})
+}
+
+func Benchmark_EncodeRawMessage_GoJson(b *testing.B) {
+	b.ReportAllocs()
+
+	m := struct {
+		A int
+		B json.RawMessage
+	}{}
+	b.RunParallel(func(pb *testing.PB) {
+		enc := json.NewEncoder(ioutil.Discard)
+		for pb.Next() {
+			if err := enc.Encode(&m); err != nil {
+				b.Fatal("Encode:", err)
+			}
+		}
+	})
+}
+
+func Benchmark_MarshalString_EncodingJson(b *testing.B) {
+	b.ReportAllocs()
+	j := struct {
+		Bar string `json:"bar,string"`
+	}{
+		Bar: `foobar`,
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			if _, err := stdjson.Marshal(&j); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+}
+
+func Benchmark_MarshalString_JsonIter(b *testing.B) {
+	b.ReportAllocs()
+	j := struct {
+		Bar string `json:"bar,string"`
+	}{
+		Bar: `foobar`,
+	}
+	var json = jsoniter.ConfigCompatibleWithStandardLibrary
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			if _, err := json.Marshal(&j); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+}
+
+func Benchmark_MarshalString_GoJson(b *testing.B) {
+	b.ReportAllocs()
+	j := struct {
+		Bar string `json:"bar,string"`
+	}{
+		Bar: `foobar`,
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			if _, err := json.Marshal(&j); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+}
+
+func BenchmarkCodeDecoder(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		var buf bytes.Buffer
+		dec := json.NewDecoder(&buf)
+		var r codeResponse
+		for pb.Next() {
+			buf.Write(codeJSON)
+			// hide EOF
+			buf.WriteByte('\n')
+			buf.WriteByte('\n')
+			buf.WriteByte('\n')
+			if err := dec.Decode(&r); err != nil {
+				b.Fatal("Decode:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func BenchmarkUnicodeDecoder(b *testing.B) {
+	b.ReportAllocs()
+	j := []byte(`"\uD83D\uDE01"`)
+	b.SetBytes(int64(len(j)))
+	r := bytes.NewReader(j)
+	dec := json.NewDecoder(r)
+	var out string
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if err := dec.Decode(&out); err != nil {
+			b.Fatal("Decode:", err)
+		}
+		r.Seek(0, 0)
+	}
+}
+
+func BenchmarkDecoderStream(b *testing.B) {
+	b.ReportAllocs()
+	b.StopTimer()
+	var buf bytes.Buffer
+	dec := json.NewDecoder(&buf)
+	buf.WriteString(`"` + strings.Repeat("x", 1000000) + `"` + "\n\n\n")
+	var x interface{}
+	if err := dec.Decode(&x); err != nil {
+		b.Fatal("Decode:", err)
+	}
+	ones := strings.Repeat(" 1\n", 300000) + "\n\n\n"
+	b.StartTimer()
+	for i := 0; i < b.N; i++ {
+		if i%300000 == 0 {
+			buf.WriteString(ones)
+		}
+		x = nil
+		if err := dec.Decode(&x); err != nil || x != 1.0 {
+			b.Fatalf("Decode: %v after %d", err, i)
+		}
+	}
+}
+
+func BenchmarkCodeUnmarshal(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			var r codeResponse
+			if err := json.Unmarshal(codeJSON, &r); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func BenchmarkCodeUnmarshalReuse(b *testing.B) {
+	b.ReportAllocs()
+	if codeJSON == nil {
+		b.StopTimer()
+		codeInit()
+		b.StartTimer()
+	}
+	b.RunParallel(func(pb *testing.PB) {
+		var r codeResponse
+		for pb.Next() {
+			if err := json.Unmarshal(codeJSON, &r); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
+		}
+	})
+	b.SetBytes(int64(len(codeJSON)))
+}
+
+func BenchmarkUnmarshalString(b *testing.B) {
+	b.ReportAllocs()
+	data := []byte(`"hello, world"`)
+	b.RunParallel(func(pb *testing.PB) {
+		var s string
+		for pb.Next() {
+			if err := json.Unmarshal(data, &s); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
+		}
+	})
+}
+
+func BenchmarkUnmarshalFloat64(b *testing.B) {
+	b.ReportAllocs()
+	data := []byte(`3.14`)
+	b.RunParallel(func(pb *testing.PB) {
+		var f float64
+		for pb.Next() {
+			if err := json.Unmarshal(data, &f); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
+		}
+	})
+}
+
+func BenchmarkUnmarshalInt64(b *testing.B) {
+	b.ReportAllocs()
+	data := []byte(`3`)
+	b.RunParallel(func(pb *testing.PB) {
+		var x int64
+		for pb.Next() {
+			if err := json.Unmarshal(data, &x); err != nil {
+				b.Fatal("Unmarshal:", err)
+			}
+		}
+	})
+}
+
+func BenchmarkIssue10335(b *testing.B) {
+	b.ReportAllocs()
+	j := []byte(`{"a":{ }}`)
+	b.RunParallel(func(pb *testing.PB) {
+		var s struct{}
+		for pb.Next() {
+			if err := json.Unmarshal(j, &s); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+}
+
+func BenchmarkUnmapped(b *testing.B) {
+	b.ReportAllocs()
+	j := []byte(`{"s": "hello", "y": 2, "o": {"x": 0}, "a": [1, 99, {"x": 1}]}`)
+	b.RunParallel(func(pb *testing.PB) {
+		var s struct{}
+		for pb.Next() {
+			if err := json.Unmarshal(j, &s); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+}
diff --git a/benchmarks/testdata/code.json.gz b/benchmarks/testdata/code.json.gz
new file mode 100644
index 0000000..1572a92
Binary files /dev/null and b/benchmarks/testdata/code.json.gz differ
diff --git a/encode.go b/encode.go
index e192e34..5cce9ad 100644
--- a/encode.go
+++ b/encode.go
@@ -3,6 +3,7 @@ package json
 import (
 	"bytes"
 	"encoding"
+	"encoding/base64"
 	"io"
 	"math"
 	"reflect"
@@ -189,6 +190,8 @@ func (e *Encoder) encode(v interface{}) error {
 	if err != nil {
 		return err
 	}
+	codeIndent = copyOpcode(codeIndent)
+	code = copyOpcode(code)
 	codeLength := code.totalLength()
 	codeSet := &opcodeSet{
 		codeIndent: codeIndent,
@@ -308,6 +311,22 @@ func (e *Encoder) encodeString(s string) {
 	}
 }
 
+func (e *Encoder) encodeByteSlice(b []byte) {
+	encodedLen := base64.StdEncoding.EncodedLen(len(b))
+	e.encodeByte('"')
+	pos := len(e.buf)
+	remainLen := cap(e.buf[pos:])
+	var buf []byte
+	if remainLen > encodedLen {
+		buf = e.buf[pos : pos+encodedLen]
+	} else {
+		buf = make([]byte, encodedLen)
+	}
+	base64.StdEncoding.Encode(buf, b)
+	e.encodeBytes(buf)
+	e.encodeByte('"')
+}
+
 func (e *Encoder) encodeByte(b byte) {
 	e.buf = append(e.buf, b)
 }
diff --git a/encode_opcode.go b/encode_opcode.go
index ea40704..a959074 100644
--- a/encode_opcode.go
+++ b/encode_opcode.go
@@ -44,6 +44,11 @@ func opcodeOffset(idx int) uintptr {
 	return uintptr(idx) * uintptrSize
 }
 
+func copyOpcode(code *opcode) *opcode {
+	codeMap := map[uintptr]*opcode{}
+	return code.copy(codeMap)
+}
+
 func newOpCodeWithNext(ctx *encodeCompileContext, op opType, next *opcode) *opcode {
 	return &opcode{
 		op:         op,
@@ -59,6 +64,43 @@ func newEndOp(ctx *encodeCompileContext) *opcode {
 	return newOpCodeWithNext(ctx, opEnd, nil)
 }
 
+func (c *opcode) copy(codeMap map[uintptr]*opcode) *opcode {
+	if c == nil {
+		return nil
+	}
+	addr := uintptr(unsafe.Pointer(c))
+	if code, exists := codeMap[addr]; exists {
+		return code
+	}
+	copied := &opcode{
+		op:           c.op,
+		typ:          c.typ,
+		displayIdx:   c.displayIdx,
+		key:          c.key,
+		displayKey:   c.displayKey,
+		isTaggedKey:  c.isTaggedKey,
+		anonymousKey: c.anonymousKey,
+		root:         c.root,
+		indent:       c.indent,
+		idx:          c.idx,
+		headIdx:      c.headIdx,
+		elemIdx:      c.elemIdx,
+		length:       c.length,
+		mapIter:      c.mapIter,
+		offset:       c.offset,
+		size:         c.size,
+	}
+	codeMap[addr] = copied
+	copied.mapKey = c.mapKey.copy(codeMap)
+	copied.mapValue = c.mapValue.copy(codeMap)
+	copied.elem = c.elem.copy(codeMap)
+	copied.end = c.end.copy(codeMap)
+	copied.nextField = c.nextField.copy(codeMap)
+	copied.next = c.next.copy(codeMap)
+	copied.jmp = c.jmp
+	return copied
+}
+
 func (c *opcode) beforeLastCode() *opcode {
 	code := c
 	for {
diff --git a/encode_vm.go b/encode_vm.go
index 29ddb30..9780a03 100644
--- a/encode_vm.go
+++ b/encode_vm.go
@@ -21,6 +21,17 @@ func store(base uintptr, idx uintptr, p uintptr) {
 	*(*uintptr)(unsafe.Pointer(base + idx)) = p
 }
 
+func errUnsupportedValue(code *opcode, ptr uintptr) *UnsupportedValueError {
+	v := *(*interface{})(unsafe.Pointer(&interfaceHeader{
+		typ: code.typ,
+		ptr: unsafe.Pointer(ptr),
+	}))
+	return &UnsupportedValueError{
+		Value: reflect.ValueOf(v),
+		Str:   fmt.Sprintf("encountered a cycle via %s", code.typ),
+	}
+}
+
 func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 	recursiveLevel := 0
 	seenPtr := map[uintptr]struct{}{}
@@ -88,13 +99,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 			if ptr == 0 || header.Data == 0 {
 				e.encodeNull()
 			} else {
-				b := e.ptrToBytes(ptr)
-				encodedLen := base64.StdEncoding.EncodedLen(len(b))
-				e.encodeByte('"')
-				buf := make([]byte, encodedLen)
-				base64.StdEncoding.Encode(buf, b)
-				e.encodeBytes(buf)
-				e.encodeByte('"')
+				e.encodeByteSlice(e.ptrToBytes(ptr))
 			}
 			code = code.next
 		case opInterface:
@@ -613,14 +618,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 			if ptr != 0 {
 				if recursiveLevel > startDetectingCyclesAfter {
 					if _, exists := seenPtr[ptr]; exists {
-						v := *(*interface{})(unsafe.Pointer(&interfaceHeader{
-							typ: code.typ,
-							ptr: unsafe.Pointer(ptr),
-						}))
-						return &UnsupportedValueError{
-							Value: reflect.ValueOf(v),
-							Str:   fmt.Sprintf("encountered a cycle via %s", code.typ),
-						}
+						return errUnsupportedValue(code, ptr)
 					}
 				}
 			}
@@ -650,7 +648,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 			}
 			ctxptr = ctx.ptr() + ptrOffset // assign new ctxptr
 
-			store(ctxptr, 0, ptr)
+			store(ctxptr, c.idx, ptr)
 			store(ctxptr, lastCode.idx, oldOffset)
 			store(ctxptr, lastCode.elemIdx, uintptr(unsafe.Pointer(code.next)))
 
@@ -661,12 +659,6 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 		case opStructFieldRecursiveEnd:
 			recursiveLevel--
 
-			// Since the pointer addresses of root code and code.jmp.code may be common,
-			// `opStructFieldRecursive` processing may replace `opEnd` of root code with `opRecursiveEnd`.
-			// At that time, `recursiveLevel` becomes -1, so return here as normal processing.
-			if recursiveLevel < 0 {
-				return nil
-			}
 			// restore ctxptr
 			offset := load(ctxptr, code.idx)
 			code = (*opcode)(unsafe.Pointer(load(ctxptr, code.elemIdx)))
@@ -1153,10 +1145,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 			} else {
 				e.encodeByte('{')
 				e.encodeBytes(code.key)
-				s := base64.StdEncoding.EncodeToString(e.ptrToBytes(ptr + code.offset))
-				e.encodeByte('"')
-				e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-				e.encodeByte('"')
+				e.encodeByteSlice(e.ptrToBytes(ptr + code.offset))
 				code = code.next
 			}
 		case opStructFieldPtrAnonymousHeadBytes:
@@ -1168,10 +1157,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 				code = code.end
 			} else {
 				e.encodeBytes(code.key)
-				s := base64.StdEncoding.EncodeToString(e.ptrToBytes(ptr + code.offset))
-				e.encodeByte('"')
-				e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-				e.encodeByte('"')
+				e.encodeByteSlice(e.ptrToBytes(ptr + code.offset))
 				code = code.next
 			}
 		case opStructFieldPtrHeadArray:
@@ -2349,10 +2335,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 					code = code.nextField
 				} else {
 					e.encodeBytes(code.key)
-					s := base64.StdEncoding.EncodeToString(v)
-					e.encodeByte('"')
-					e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-					e.encodeByte('"')
+					e.encodeByteSlice(v)
 					code = code.next
 				}
 			}
@@ -2372,10 +2355,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 					code = code.nextField
 				} else {
 					e.encodeBytes(code.key)
-					s := base64.StdEncoding.EncodeToString(v)
-					e.encodeByte('"')
-					e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-					e.encodeByte('"')
+					e.encodeByteSlice(v)
 					code = code.next
 				}
 			}
@@ -3461,12 +3441,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 			} else {
 				e.encodeByte('{')
 				e.encodeBytes(code.key)
-				s := base64.StdEncoding.EncodeToString(
-					e.ptrToBytes(ptr + code.offset),
-				)
-				e.encodeByte('"')
-				e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-				e.encodeByte('"')
+				e.encodeByteSlice(e.ptrToBytes(ptr + code.offset))
 				code = code.next
 			}
 		case opStructFieldPtrAnonymousHeadStringTagBytes:
@@ -3481,12 +3456,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 				code = code.end.next
 			} else {
 				e.encodeBytes(code.key)
-				s := base64.StdEncoding.EncodeToString(
-					e.ptrToBytes(ptr + code.offset),
-				)
-				e.encodeByte('"')
-				e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-				e.encodeByte('"')
+				e.encodeByteSlice(e.ptrToBytes(ptr + code.offset))
 				code = code.next
 			}
 		case opStructFieldPtrHeadStringTagMarshalJSON:
@@ -4090,10 +4060,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 			}
 			ptr := load(ctxptr, code.headIdx)
 			e.encodeBytes(code.key)
-			s := base64.StdEncoding.EncodeToString(e.ptrToBytes(ptr + code.offset))
-			e.encodeByte('"')
-			e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-			e.encodeByte('"')
+			e.encodeByteSlice(e.ptrToBytes(ptr + code.offset))
 			code = code.next
 		case opStructFieldMarshalJSON:
 			if e.buf[len(e.buf)-1] != '{' {
@@ -4661,10 +4628,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 					e.encodeByte(',')
 				}
 				e.encodeBytes(code.key)
-				s := base64.StdEncoding.EncodeToString(v)
-				e.encodeByte('"')
-				e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-				e.encodeByte('"')
+				e.encodeByteSlice(v)
 			}
 			code = code.next
 		case opStructFieldOmitEmptyMarshalJSON:
@@ -5213,10 +5177,7 @@ func (e *Encoder) run(ctx *encodeRuntimeContext, code *opcode) error {
 				e.encodeByte(',')
 			}
 			e.encodeBytes(code.key)
-			s := base64.StdEncoding.EncodeToString(v)
-			e.encodeByte('"')
-			e.encodeBytes(*(*[]byte)(unsafe.Pointer(&s)))
-			e.encodeByte('"')
+			e.encodeByteSlice(v)
 			code = code.next
 		case opStructFieldStringTagMarshalJSON:
 			ptr := load(ctxptr, code.headIdx)