Imported Upstream version 58upstream/58

2 files changed, 175 insertions, 0 deletions

diff --git a/src/pkg/encoding/binary/binary.go b/src/pkg/encoding/binary/binary.go
index a01d0e024..8e55cb23b 100644
--- a/src/pkg/encoding/binary/binary.go
+++ b/src/pkg/encoding/binary/binary.go
@@ -125,6 +125,35 @@ func (bigEndian) GoString() string { return "binary.BigEndian" }
 // Bytes read from r are decoded using the specified byte order
 // and written to successive fields of the data.
 func Read(r io.Reader, order ByteOrder, data interface{}) os.Error {
+	// Fast path for basic types.
+	if n := intDestSize(data); n != 0 {
+		var b [8]byte
+		bs := b[:n]
+		if _, err := io.ReadFull(r, bs); err != nil {
+			return err
+		}
+		switch v := data.(type) {
+		case *int8:
+			*v = int8(b[0])
+		case *uint8:
+			*v = b[0]
+		case *int16:
+			*v = int16(order.Uint16(bs))
+		case *uint16:
+			*v = order.Uint16(bs)
+		case *int32:
+			*v = int32(order.Uint32(bs))
+		case *uint32:
+			*v = order.Uint32(bs)
+		case *int64:
+			*v = int64(order.Uint64(bs))
+		case *uint64:
+			*v = order.Uint64(bs)
+		}
+		return nil
+	}
+
+	// Fallback to reflect-based.
 	var v reflect.Value
 	switch d := reflect.ValueOf(data); d.Kind() {
 	case reflect.Ptr:
@@ -155,6 +184,63 @@ func Read(r io.Reader, order ByteOrder, data interface{}) os.Error {
 // Bytes written to w are encoded using the specified byte order
 // and read from successive fields of the data.
 func Write(w io.Writer, order ByteOrder, data interface{}) os.Error {
+	// Fast path for basic types.
+	var b [8]byte
+	var bs []byte
+	switch v := data.(type) {
+	case *int8:
+		bs = b[:1]
+		b[0] = byte(*v)
+	case int8:
+		bs = b[:1]
+		b[0] = byte(v)
+	case *uint8:
+		bs = b[:1]
+		b[0] = *v
+	case uint8:
+		bs = b[:1]
+		b[0] = byte(v)
+	case *int16:
+		bs = b[:2]
+		order.PutUint16(bs, uint16(*v))
+	case int16:
+		bs = b[:2]
+		order.PutUint16(bs, uint16(v))
+	case *uint16:
+		bs = b[:2]
+		order.PutUint16(bs, *v)
+	case uint16:
+		bs = b[:2]
+		order.PutUint16(bs, v)
+	case *int32:
+		bs = b[:4]
+		order.PutUint32(bs, uint32(*v))
+	case int32:
+		bs = b[:4]
+		order.PutUint32(bs, uint32(v))
+	case *uint32:
+		bs = b[:4]
+		order.PutUint32(bs, *v)
+	case uint32:
+		bs = b[:4]
+		order.PutUint32(bs, v)
+	case *int64:
+		bs = b[:8]
+		order.PutUint64(bs, uint64(*v))
+	case int64:
+		bs = b[:8]
+		order.PutUint64(bs, uint64(v))
+	case *uint64:
+		bs = b[:8]
+		order.PutUint64(bs, *v)
+	case uint64:
+		bs = b[:8]
+		order.PutUint64(bs, v)
+	}
+	if bs != nil {
+		_, err := w.Write(bs)
+		return err
+	}
 	v := reflect.Indirect(reflect.ValueOf(data))
 	size := TotalSize(v)
 	if size < 0 {
@@ -394,3 +480,19 @@ func (e *encoder) value(v reflect.Value) {
 		}
 	}
 }
+
+// intDestSize returns the size of the integer that ptrType points to,
+// or 0 if the type is not supported.
+func intDestSize(ptrType interface{}) int {
+	switch ptrType.(type) {
+	case *int8, *uint8:
+		return 1
+	case *int16, *uint16:
+		return 2
+	case *int32, *uint32:
+		return 4
+	case *int64, *uint64:
+		return 8
+	}
+	return 0
+}
diff --git a/src/pkg/encoding/binary/binary_test.go b/src/pkg/encoding/binary/binary_test.go
index 7857c68d3..b266996f6 100644
--- a/src/pkg/encoding/binary/binary_test.go
+++ b/src/pkg/encoding/binary/binary_test.go
@@ -5,6 +5,7 @@
 package binary
 
 import (
+	"io"
 	"os"
 	"bytes"
 	"math"
@@ -160,3 +161,75 @@ func TestWriteT(t *testing.T) {
 		}
 	}
 }
+
+type byteSliceReader struct {
+	remain []byte
+}
+
+func (br *byteSliceReader) Read(p []byte) (int, os.Error) {
+	n := copy(p, br.remain)
+	br.remain = br.remain[n:]
+	return n, nil
+}
+
+func BenchmarkRead(b *testing.B) {
+	var ls Struct
+	bsr := &byteSliceReader{}
+	var r io.Reader = bsr
+
+	for i := 0; i < b.N; i++ {
+		bsr.remain = big
+		Read(r, BigEndian, &ls.Int8)
+		Read(r, BigEndian, &ls.Int16)
+		Read(r, BigEndian, &ls.Int32)
+		Read(r, BigEndian, &ls.Int64)
+		Read(r, BigEndian, &ls.Uint8)
+		Read(r, BigEndian, &ls.Uint16)
+		Read(r, BigEndian, &ls.Uint32)
+		Read(r, BigEndian, &ls.Uint64)
+	}
+
+	want := s
+	want.Float32 = 0
+	want.Float64 = 0
+	want.Complex64 = 0
+	want.Complex128 = 0
+	for i := range want.Array {
+		want.Array[i] = 0
+	}
+	if !reflect.DeepEqual(ls, want) {
+		panic("no match")
+	}
+}
+
+func BenchmarkWrite(b *testing.B) {
+	buf := new(bytes.Buffer)
+	var w io.Writer = buf
+
+	for i := 0; i < b.N; i++ {
+		buf.Reset()
+		Write(w, BigEndian, &s.Int8)
+		Write(w, BigEndian, &s.Int16)
+		Write(w, BigEndian, &s.Int32)
+		Write(w, BigEndian, &s.Int64)
+		Write(w, BigEndian, &s.Uint8)
+		Write(w, BigEndian, &s.Uint16)
+		Write(w, BigEndian, &s.Uint32)
+		Write(w, BigEndian, &s.Uint64)
+		Write(w, BigEndian, s.Int8)
+		Write(w, BigEndian, s.Int16)
+		Write(w, BigEndian, s.Int32)
+		Write(w, BigEndian, s.Int64)
+		Write(w, BigEndian, s.Uint8)
+		Write(w, BigEndian, s.Uint16)
+		Write(w, BigEndian, s.Uint32)
+		Write(w, BigEndian, s.Uint64)
+	}
+
+	if !bytes.Equal(buf.Bytes()[:30], big[:30]) {
+		panic("first half doesn't match")
+	}
+	if !bytes.Equal(buf.Bytes()[30:], big[:30]) {
+		panic("second half doesn't match")
+	}
+}