diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go
index 5e99149d25..60124e3212 100644
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -1757,26 +1757,6 @@ func addsection(arch *sys.Arch, seg *sym.Segment, name string, rwx int) *sym.Sec
 	return sect
 }
 
-func Le16(b []byte) uint16 {
-	return uint16(b[0]) | uint16(b[1])<<8
-}
-
-func Le32(b []byte) uint32 {
-	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
-}
-
-func Le64(b []byte) uint64 {
-	return uint64(Le32(b)) | uint64(Le32(b[4:]))<<32
-}
-
-func Be16(b []byte) uint16 {
-	return uint16(b[0])<<8 | uint16(b[1])
-}
-
-func Be32(b []byte) uint32 {
-	return uint32(b[0])<<24 | uint32(b[1])<<16 | uint32(b[2])<<8 | uint32(b[3])
-}
-
 type chain struct {
 	sym   *sym.Symbol
 	up    *chain
diff --git a/src/cmd/link/internal/ppc64/asm.go b/src/cmd/link/internal/ppc64/asm.go
index 9445fbebcb..3e833b686e 100644
--- a/src/cmd/link/internal/ppc64/asm.go
+++ b/src/cmd/link/internal/ppc64/asm.go
@@ -716,9 +716,9 @@ func archrelocvariant(ctxt *ld.Link, r *sym.Reloc, s *sym.Symbol, t int64) int64
 			// overflow depends on the instruction
 			var o1 uint32
 			if ctxt.Arch.ByteOrder == binary.BigEndian {
-				o1 = ld.Be32(s.P[r.Off-2:])
+				o1 = binary.BigEndian.Uint32(s.P[r.Off-2:])
 			} else {
-				o1 = ld.Le32(s.P[r.Off:])
+				o1 = binary.LittleEndian.Uint32(s.P[r.Off:])
 			}
 			switch o1 >> 26 {
 			case 24, // ori
@@ -750,9 +750,9 @@ func archrelocvariant(ctxt *ld.Link, r *sym.Reloc, s *sym.Symbol, t int64) int64
 			// overflow depends on the instruction
 			var o1 uint32
 			if ctxt.Arch.ByteOrder == binary.BigEndian {
-				o1 = ld.Be32(s.P[r.Off-2:])
+				o1 = binary.BigEndian.Uint32(s.P[r.Off-2:])
 			} else {
-				o1 = ld.Le32(s.P[r.Off:])
+				o1 = binary.LittleEndian.Uint32(s.P[r.Off:])
 			}
 			switch o1 >> 26 {
 			case 25, // oris
@@ -774,9 +774,9 @@ func archrelocvariant(ctxt *ld.Link, r *sym.Reloc, s *sym.Symbol, t int64) int64
 	case sym.RV_POWER_DS:
 		var o1 uint32
 		if ctxt.Arch.ByteOrder == binary.BigEndian {
-			o1 = uint32(ld.Be16(s.P[r.Off:]))
+			o1 = uint32(binary.BigEndian.Uint16(s.P[r.Off:]))
 		} else {
-			o1 = uint32(ld.Le16(s.P[r.Off:]))
+			o1 = uint32(binary.LittleEndian.Uint16(s.P[r.Off:]))
 		}
 		if t&3 != 0 {
 			ld.Errorf(s, "relocation for %s+%d is not aligned: %d", r.Sym.Name, r.Off, t)
diff --git a/src/compress/zlib/writer.go b/src/compress/zlib/writer.go
index a7b219467e..9986e3834d 100644
--- a/src/compress/zlib/writer.go
+++ b/src/compress/zlib/writer.go
@@ -6,6 +6,7 @@ package zlib
 
 import (
 	"compress/flate"
+	"encoding/binary"
 	"fmt"
 	"hash"
 	"hash/adler32"
@@ -120,11 +121,7 @@ func (z *Writer) writeHeader() (err error) {
 	}
 	if z.dict != nil {
 		// The next four bytes are the Adler-32 checksum of the dictionary.
-		checksum := adler32.Checksum(z.dict)
-		z.scratch[0] = uint8(checksum >> 24)
-		z.scratch[1] = uint8(checksum >> 16)
-		z.scratch[2] = uint8(checksum >> 8)
-		z.scratch[3] = uint8(checksum >> 0)
+		binary.BigEndian.PutUint32(z.scratch[:], adler32.Checksum(z.dict))
 		if _, err = z.w.Write(z.scratch[0:4]); err != nil {
 			return err
 		}
@@ -190,10 +187,7 @@ func (z *Writer) Close() error {
 	}
 	checksum := z.digest.Sum32()
 	// ZLIB (RFC 1950) is big-endian, unlike GZIP (RFC 1952).
-	z.scratch[0] = uint8(checksum >> 24)
-	z.scratch[1] = uint8(checksum >> 16)
-	z.scratch[2] = uint8(checksum >> 8)
-	z.scratch[3] = uint8(checksum >> 0)
+	binary.BigEndian.PutUint32(z.scratch[:], checksum)
 	_, z.err = z.w.Write(z.scratch[0:4])
 	return z.err
 }
diff --git a/src/image/png/writer.go b/src/image/png/writer.go
index 49f1ad2e7f..de8c28e919 100644
--- a/src/image/png/writer.go
+++ b/src/image/png/writer.go
@@ -7,6 +7,7 @@ package png
 import (
 	"bufio"
 	"compress/zlib"
+	"encoding/binary"
 	"hash/crc32"
 	"image"
 	"image/color"
@@ -62,14 +63,6 @@ const (
 	// compression level, although that is not implemented yet.
 )
 
-// Big-endian.
-func writeUint32(b []uint8, u uint32) {
-	b[0] = uint8(u >> 24)
-	b[1] = uint8(u >> 16)
-	b[2] = uint8(u >> 8)
-	b[3] = uint8(u >> 0)
-}
-
 type opaquer interface {
 	Opaque() bool
 }
@@ -108,7 +101,7 @@ func (e *encoder) writeChunk(b []byte, name string) {
 		e.err = UnsupportedError(name + " chunk is too large: " + strconv.Itoa(len(b)))
 		return
 	}
-	writeUint32(e.header[:4], n)
+	binary.BigEndian.PutUint32(e.header[:4], n)
 	e.header[4] = name[0]
 	e.header[5] = name[1]
 	e.header[6] = name[2]
@@ -116,7 +109,7 @@ func (e *encoder) writeChunk(b []byte, name string) {
 	crc := crc32.NewIEEE()
 	crc.Write(e.header[4:8])
 	crc.Write(b)
-	writeUint32(e.footer[:4], crc.Sum32())
+	binary.BigEndian.PutUint32(e.footer[:4], crc.Sum32())
 
 	_, e.err = e.w.Write(e.header[:8])
 	if e.err != nil {
@@ -131,8 +124,8 @@ func (e *encoder) writeChunk(b []byte, name string) {
 
 func (e *encoder) writeIHDR() {
 	b := e.m.Bounds()
-	writeUint32(e.tmp[0:4], uint32(b.Dx()))
-	writeUint32(e.tmp[4:8], uint32(b.Dy()))
+	binary.BigEndian.PutUint32(e.tmp[0:4], uint32(b.Dx()))
+	binary.BigEndian.PutUint32(e.tmp[4:8], uint32(b.Dy()))
 	// Set bit depth and color type.
 	switch e.cb {
 	case cbG8: