runtime: use internal/byteorder

To simplify the code.

Change-Id: Ib1af5009cc25bb29fd26fdb7b29ff4579f0150aa
GitHub-Last-Rev: f698a8a771ac8c6ecb745ea4c27a7c677c1789d1
GitHub-Pull-Request: golang/go#73255
Reviewed-on: https://go-review.googlesource.com/c/go/+/663735
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

src/runtime/alg.go

@@ -6,6 +6,7 @@ package runtime
 
 import (
 	"internal/abi"
+	"internal/byteorder"
 	"internal/cpu"
 	"internal/goarch"
 	"internal/runtime/sys"
@@ -474,16 +475,15 @@ func initAlgAES() {
 func readUnaligned32(p unsafe.Pointer) uint32 {
 	q := (*[4]byte)(p)
 	if goarch.BigEndian {
-		return uint32(q[3]) | uint32(q[2])<<8 | uint32(q[1])<<16 | uint32(q[0])<<24
+		return byteorder.BEUint32(q[:])
 	}
-	return uint32(q[0]) | uint32(q[1])<<8 | uint32(q[2])<<16 | uint32(q[3])<<24
+	return byteorder.LEUint32(q[:])
 }
 
 func readUnaligned64(p unsafe.Pointer) uint64 {
 	q := (*[8]byte)(p)
 	if goarch.BigEndian {
-		return uint64(q[7]) | uint64(q[6])<<8 | uint64(q[5])<<16 | uint64(q[4])<<24 |
+		return byteorder.BEUint64(q[:])
-			uint64(q[3])<<32 | uint64(q[2])<<40 | uint64(q[1])<<48 | uint64(q[0])<<56
 	}
-	return uint64(q[0]) | uint64(q[1])<<8 | uint64(q[2])<<16 | uint64(q[3])<<24 | uint64(q[4])<<32 | uint64(q[5])<<40 | uint64(q[6])<<48 | uint64(q[7])<<56
+	return byteorder.LEUint64(q[:])
 }

src/runtime/debuglog.go

@@ -27,6 +27,7 @@ package runtime
 
 import (
 	"internal/abi"
+	"internal/byteorder"
 	"internal/runtime/atomic"
 	"internal/runtime/sys"
 	"unsafe"
@@ -477,14 +478,7 @@ func (l *debugLogWriter) writeSync(tick, nano uint64) {
 //go:nosplit
 func (l *debugLogWriter) writeUint64LE(x uint64) {
 	var b [8]byte
-	b[0] = byte(x)
+	byteorder.LEPutUint64(b[:], x)
-	b[1] = byte(x >> 8)
-	b[2] = byte(x >> 16)
-	b[3] = byte(x >> 24)
-	b[4] = byte(x >> 32)
-	b[5] = byte(x >> 40)
-	b[6] = byte(x >> 48)
-	b[7] = byte(x >> 56)
 	l.bytes(b[:])
 }
 
@@ -576,10 +570,7 @@ func (r *debugLogReader) readUint64LEAt(pos uint64) uint64 {
 		b[i] = r.data.b[pos%uint64(len(r.data.b))]
 		pos++
 	}
-	return uint64(b[0]) | uint64(b[1])<<8 |
+	return byteorder.LEUint64(b[:])
-		uint64(b[2])<<16 | uint64(b[3])<<24 |
-		uint64(b[4])<<32 | uint64(b[5])<<40 |
-		uint64(b[6])<<48 | uint64(b[7])<<56
 }
 
 func (r *debugLogReader) peek() (tick uint64) {

src/runtime/hash_test.go

@@ -7,6 +7,7 @@ package runtime_test
 import (
 	"encoding/binary"
 	"fmt"
+	"internal/byteorder"
 	"internal/race"
 	"internal/testenv"
 	"math"
@@ -326,10 +327,7 @@ func genPerm(h *HashSet, b []byte, s []uint32, n int) {
 		return
 	}
 	for _, v := range s {
-		b[n] = byte(v)
+		byteorder.LEPutUint32(b[n:], v)
-		b[n+1] = byte(v >> 8)
-		b[n+2] = byte(v >> 16)
-		b[n+3] = byte(v >> 24)
 		genPerm(h, b, s, n+4)
 	}
 }

src/runtime/os_plan9.go

@@ -6,6 +6,7 @@ package runtime
 
 import (
 	"internal/abi"
+	"internal/byteorder"
 	"internal/runtime/atomic"
 	"internal/stringslite"
 	"unsafe"
@@ -574,8 +575,7 @@ func timesplit(u uint64) (sec int64, nsec int32)
 
 func frombe(u uint64) uint64 {
 	b := (*[8]byte)(unsafe.Pointer(&u))
-	return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
+	return byteorder.BEUint64(b[:])
-		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
 }
 
 //go:nosplit

src/runtime/pprof/vminfo_darwin.go

@@ -5,6 +5,7 @@
 package pprof
 
 import (
+	"internal/byteorder"
 	"os"
 	"unsafe"
 )
@@ -39,7 +40,7 @@ func machVMInfo(addMapping func(lo, hi, offset uint64, file, buildID string)) bo
 			// offset is usually 0.
 			addMapping(addr,
 				addr+memRegionSize,
-				read64(&info.Offset),
+				byteorder.LEUint64(info.Offset[:]),
 				regionFilename(addr),
 				"")
 			added = true
@@ -48,11 +49,6 @@ func machVMInfo(addMapping func(lo, hi, offset uint64, file, buildID string)) bo
 	}
 }
 
-func read64(p *[8]byte) uint64 {
-	// all supported darwin platforms are little endian
-	return uint64(p[0]) | uint64(p[1])<<8 | uint64(p[2])<<16 | uint64(p[3])<<24 | uint64(p[4])<<32 | uint64(p[5])<<40 | uint64(p[6])<<48 | uint64(p[7])<<56
-}
-
 func regionFilename(address uint64) string {
 	buf := make([]byte, _MAXPATHLEN)
 	r := proc_regionfilename(

src/runtime/write_err_android.go

@@ -4,7 +4,10 @@
 
 package runtime
 
-import "unsafe"
+import (
+	"internal/byteorder"
+	"unsafe"
+)
 
 var (
 	writeHeader = []byte{6 /* ANDROID_LOG_ERROR */, 'G', 'o', 0}
@@ -148,18 +151,10 @@ func writeLogdHeader() int {
 	//      hdr[7:11] nsec unsigned uint32, little endian.
 	hdr[0] = 0 // LOG_ID_MAIN
 	sec, nsec, _ := time_now()
-	packUint32(hdr[3:7], uint32(sec))
+	byteorder.LEPutUint32(hdr[3:7], uint32(sec))
-	packUint32(hdr[7:11], uint32(nsec))
+	byteorder.LEPutUint32(hdr[7:11], uint32(nsec))
 
 	// TODO(hakim):  hdr[1:2] = gettid?
 
 	return 11 + len(writeHeader)
 }
-
-func packUint32(b []byte, v uint32) {
-	// little-endian.
-	b[0] = byte(v)
-	b[1] = byte(v >> 8)
-	b[2] = byte(v >> 16)
-	b[3] = byte(v >> 24)
-}