[dev.link] all: merge branch 'master' into dev.link

Clean merge.

Change-Id: I2ae070c60c011779a0f0a1344f5b6d45ef10d8a1

src/bytes/bytes.go

@@ -183,6 +183,29 @@ func IndexAny(s []byte, chars string) int {
 		// Avoid scanning all of s.
 		return -1
 	}
+	if len(s) == 1 {
+		r := rune(s[0])
+		if r >= utf8.RuneSelf {
+			// search utf8.RuneError.
+			for _, r = range chars {
+				if r == utf8.RuneError {
+					return 0
+				}
+			}
+			return -1
+		}
+		if bytealg.IndexByteString(chars, s[0]) >= 0 {
+			return 0
+		}
+		return -1
+	}
+	if len(chars) == 1 {
+		r := rune(chars[0])
+		if r >= utf8.RuneSelf {
+			r = utf8.RuneError
+		}
+		return IndexRune(s, r)
+	}
 	if len(s) > 8 {
 		if as, isASCII := makeASCIISet(chars); isASCII {
 			for i, c := range s {
@@ -197,14 +220,26 @@ func IndexAny(s []byte, chars string) int {
 	for i := 0; i < len(s); i += width {
 		r := rune(s[i])
 		if r < utf8.RuneSelf {
-			width = 1
-		} else {
-			r, width = utf8.DecodeRune(s[i:])
-		}
-		for _, ch := range chars {
-			if r == ch {
+			if bytealg.IndexByteString(chars, s[i]) >= 0 {
 				return i
 			}
+			width = 1
+			continue
+		}
+		r, width = utf8.DecodeRune(s[i:])
+		if r == utf8.RuneError {
+			for _, r = range chars {
+				if r == utf8.RuneError {
+					return i
+				}
+			}
+			continue
+		}
+		// r is 2 to 4 bytes. Using strings.Index is more reasonable, but as the bytes
+		// package should not import the strings package, use bytealg.IndexString
+		// instead. And this does not seem to lose much performance.
+		if chars == string(r) || bytealg.IndexString(chars, string(r)) >= 0 {
+			return i
 		}
 	}
 	return -1
@@ -229,14 +264,60 @@ func LastIndexAny(s []byte, chars string) int {
 			return -1
 		}
 	}
-	for i := len(s); i > 0; {
-		r, size := utf8.DecodeLastRune(s[:i])
-		i -= size
-		for _, c := range chars {
-			if r == c {
+	if len(s) == 1 {
+		r := rune(s[0])
+		if r >= utf8.RuneSelf {
+			for _, r = range chars {
+				if r == utf8.RuneError {
+					return 0
+				}
+			}
+			return -1
+		}
+		if bytealg.IndexByteString(chars, s[0]) >= 0 {
+			return 0
+		}
+		return -1
+	}
+	if len(chars) == 1 {
+		cr := rune(chars[0])
+		if cr >= utf8.RuneSelf {
+			cr = utf8.RuneError
+		}
+		for i := len(s); i > 0; {
+			r, size := utf8.DecodeLastRune(s[:i])
+			i -= size
+			if r == cr {
 				return i
 			}
 		}
+		return -1
+	}
+	for i := len(s); i > 0; {
+		r := rune(s[i-1])
+		if r < utf8.RuneSelf {
+			if bytealg.IndexByteString(chars, s[i-1]) >= 0 {
+				return i - 1
+			}
+			i--
+			continue
+		}
+		r, size := utf8.DecodeLastRune(s[:i])
+		i -= size
+		if r == utf8.RuneError {
+			for _, r = range chars {
+				if r == utf8.RuneError {
+					return i
+				}
+			}
+			continue
+		}
+		// r is 2 to 4 bytes. Using strings.Index is more reasonable, but as the bytes
+		// package should not import the strings package, use bytealg.IndexString
+		// instead. And this does not seem to lose much performance.
+		if chars == string(r) || bytealg.IndexString(chars, string(r)) >= 0 {
+			return i
+		}
 	}
 	return -1
 }

src/bytes/bytes_test.go

@@ -169,6 +169,7 @@ var indexAnyTests = []BinOpTest{
 	{"", "abc", -1},
 	{"a", "", -1},
 	{"a", "a", 0},
+	{"\x80", "\xffb", 0},
 	{"aaa", "a", 0},
 	{"abc", "xyz", -1},
 	{"abc", "xcz", 2},
@@ -179,6 +180,7 @@ var indexAnyTests = []BinOpTest{
 	{dots + dots + dots, " ", -1},
 	{"012abcba210", "\xffb", 4},
 	{"012\x80bcb\x80210", "\xffb", 3},
+	{"0123456\xcf\x80abc", "\xcfb\x80", 10},
 }
 
 var lastIndexAnyTests = []BinOpTest{
@@ -187,6 +189,7 @@ var lastIndexAnyTests = []BinOpTest{
 	{"", "abc", -1},
 	{"a", "", -1},
 	{"a", "a", 0},
+	{"\x80", "\xffb", 0},
 	{"aaa", "a", 2},
 	{"abc", "xyz", -1},
 	{"abc", "ab", 1},
@@ -197,6 +200,7 @@ var lastIndexAnyTests = []BinOpTest{
 	{dots + dots + dots, " ", -1},
 	{"012abcba210", "\xffb", 6},
 	{"012\x80bcb\x80210", "\xffb", 7},
+	{"0123456\xcf\x80abc", "\xcfb\x80", 10},
 }
 
 // Execute f on each test case.  funcName should be the name of f; it's used
@@ -1890,10 +1894,10 @@ func BenchmarkBytesCompare(b *testing.B) {
 }
 
 func BenchmarkIndexAnyASCII(b *testing.B) {
-	x := Repeat([]byte{'#'}, 4096) // Never matches set
-	cs := "0123456789abcdef"
-	for k := 1; k <= 4096; k <<= 4 {
-		for j := 1; j <= 16; j <<= 1 {
+	x := Repeat([]byte{'#'}, 2048) // Never matches set
+	cs := "0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz"
+	for k := 1; k <= 2048; k <<= 4 {
+		for j := 1; j <= 64; j <<= 1 {
 			b.Run(fmt.Sprintf("%d:%d", k, j), func(b *testing.B) {
 				for i := 0; i < b.N; i++ {
 					IndexAny(x[:k], cs[:j])
@@ -1903,6 +1907,48 @@ func BenchmarkIndexAnyASCII(b *testing.B) {
 	}
 }
 
+func BenchmarkIndexAnyUTF8(b *testing.B) {
+	x := Repeat([]byte{'#'}, 2048) // Never matches set
+	cs := "你好世界, hello world. 你好世界, hello world. 你好世界, hello world."
+	for k := 1; k <= 2048; k <<= 4 {
+		for j := 1; j <= 64; j <<= 1 {
+			b.Run(fmt.Sprintf("%d:%d", k, j), func(b *testing.B) {
+				for i := 0; i < b.N; i++ {
+					IndexAny(x[:k], cs[:j])
+				}
+			})
+		}
+	}
+}
+
+func BenchmarkLastIndexAnyASCII(b *testing.B) {
+	x := Repeat([]byte{'#'}, 2048) // Never matches set
+	cs := "0123456789abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz"
+	for k := 1; k <= 2048; k <<= 4 {
+		for j := 1; j <= 64; j <<= 1 {
+			b.Run(fmt.Sprintf("%d:%d", k, j), func(b *testing.B) {
+				for i := 0; i < b.N; i++ {
+					LastIndexAny(x[:k], cs[:j])
+				}
+			})
+		}
+	}
+}
+
+func BenchmarkLastIndexAnyUTF8(b *testing.B) {
+	x := Repeat([]byte{'#'}, 2048) // Never matches set
+	cs := "你好世界, hello world. 你好世界, hello world. 你好世界, hello world."
+	for k := 1; k <= 2048; k <<= 4 {
+		for j := 1; j <= 64; j <<= 1 {
+			b.Run(fmt.Sprintf("%d:%d", k, j), func(b *testing.B) {
+				for i := 0; i < b.N; i++ {
+					LastIndexAny(x[:k], cs[:j])
+				}
+			})
+		}
+	}
+}
+
 func BenchmarkTrimASCII(b *testing.B) {
 	cs := "0123456789abcdef"
 	for k := 1; k <= 4096; k <<= 4 {

src/cmd/asm/internal/asm/testdata/ppc64.s

@@ -1064,7 +1064,7 @@ label1:
 //	VSX AND, XX3-form
 //	<MNEMONIC> XA,XB,XT produces
 //	<mnemonic> XT,XA,XB
-	XXLANDQ	    VS0,VS1,VS32
+	XXLAND	    VS0,VS1,VS32
 	XXLANDC	    VS0,VS1,VS32
 	XXLEQV	    VS0,VS1,VS32
 	XXLNAND	    VS0,VS1,VS32
@@ -1093,6 +1093,11 @@ label1:
 //	<mnemonic> XT,XB,UIM
 	XXSPLTW	    VS0,$3,VS32
 
+//      VSX permute, XX3-form
+//      <MNEMONIC> XA,XB,XT produces
+//      <mnemonic> XT,XA,XB
+        XXPERM    VS0,VS1,VS32
+
 //	VSX permute, XX3-form
 //	<MNEMONIC> XA,XB,DM,XT produces
 //	<mnemonic> XT,XA,XB,DM

src/cmd/cgo/out.go

@@ -22,6 +22,7 @@ import (
 	"regexp"
 	"sort"
 	"strings"
+	"unicode"
 )
 
 var (
@@ -802,6 +803,28 @@ func (p *Package) packedAttribute() string {
 	return s + "))"
 }
 
+// exportParamName returns the value of param as it should be
+// displayed in a c header file. If param contains any non-ASCII
+// characters, this function will return the character p followed by
+// the value of position; otherwise, this function will return the
+// value of param.
+func exportParamName(param string, position int) string {
+	if param == "" {
+		return fmt.Sprintf("p%d", position)
+	}
+
+	pname := param
+
+	for i := 0; i < len(param); i++ {
+		if param[i] > unicode.MaxASCII {
+			pname = fmt.Sprintf("p%d", position)
+			break
+		}
+	}
+
+	return pname
+}
+
 // Write out the various stubs we need to support functions exported
 // from Go so that they are callable from C.
 func (p *Package) writeExports(fgo2, fm, fgcc, fgcch io.Writer) {
@@ -915,42 +938,45 @@ func (p *Package) writeExports(fgo2, fm, fgcc, fgcch io.Writer) {
 				if i > 0 || fn.Recv != nil {
 					s += ", "
 				}
-				s += fmt.Sprintf("%s p%d", p.cgoType(atype).C, i)
+				s += fmt.Sprintf("%s %s", p.cgoType(atype).C, exportParamName(aname, i))
 			})
 		s += ")"
 
 		if len(exp.Doc) > 0 {
 			fmt.Fprintf(fgcch, "\n%s", exp.Doc)
+			if !strings.HasSuffix(exp.Doc, "\n") {
+				fmt.Fprint(fgcch, "\n")
+			}
 		}
-		fmt.Fprintf(fgcch, "\nextern %s;\n", s)
+		fmt.Fprintf(fgcch, "extern %s;\n", s)
 
 		fmt.Fprintf(fgcc, "extern void _cgoexp%s_%s(void *, int, __SIZE_TYPE__);\n", cPrefix, exp.ExpName)
 		fmt.Fprintf(fgcc, "\nCGO_NO_SANITIZE_THREAD")
 		fmt.Fprintf(fgcc, "\n%s\n", s)
 		fmt.Fprintf(fgcc, "{\n")
 		fmt.Fprintf(fgcc, "\t__SIZE_TYPE__ _cgo_ctxt = _cgo_wait_runtime_init_done();\n")
-		fmt.Fprintf(fgcc, "\t%s %v a;\n", ctype, p.packedAttribute())
+		fmt.Fprintf(fgcc, "\t%s %v _cgo_a;\n", ctype, p.packedAttribute())
 		if gccResult != "void" && (len(fntype.Results.List) > 1 || len(fntype.Results.List[0].Names) > 1) {
 			fmt.Fprintf(fgcc, "\t%s r;\n", gccResult)
 		}
 		if fn.Recv != nil {
-			fmt.Fprintf(fgcc, "\ta.recv = recv;\n")
+			fmt.Fprintf(fgcc, "\t_cgo_a.recv = recv;\n")
 		}
 		forFieldList(fntype.Params,
 			func(i int, aname string, atype ast.Expr) {
-				fmt.Fprintf(fgcc, "\ta.p%d = p%d;\n", i, i)
+				fmt.Fprintf(fgcc, "\t_cgo_a.p%d = %s;\n", i, exportParamName(aname, i))
 			})
 		fmt.Fprintf(fgcc, "\t_cgo_tsan_release();\n")
-		fmt.Fprintf(fgcc, "\tcrosscall2(_cgoexp%s_%s, &a, %d, _cgo_ctxt);\n", cPrefix, exp.ExpName, off)
+		fmt.Fprintf(fgcc, "\tcrosscall2(_cgoexp%s_%s, &_cgo_a, %d, _cgo_ctxt);\n", cPrefix, exp.ExpName, off)
 		fmt.Fprintf(fgcc, "\t_cgo_tsan_acquire();\n")
 		fmt.Fprintf(fgcc, "\t_cgo_release_context(_cgo_ctxt);\n")
 		if gccResult != "void" {
 			if len(fntype.Results.List) == 1 && len(fntype.Results.List[0].Names) <= 1 {
-				fmt.Fprintf(fgcc, "\treturn a.r0;\n")
+				fmt.Fprintf(fgcc, "\treturn _cgo_a.r0;\n")
 			} else {
 				forFieldList(fntype.Results,
 					func(i int, aname string, atype ast.Expr) {
-						fmt.Fprintf(fgcc, "\tr.r%d = a.r%d;\n", i, i)
+						fmt.Fprintf(fgcc, "\tr.r%d = _cgo_a.r%d;\n", i, i)
 					})
 				fmt.Fprintf(fgcc, "\treturn r;\n")
 			}

src/cmd/compile/doc.go

@@ -77,8 +77,6 @@ Flags:
 	-lang version
 		Set language version to compile, as in -lang=go1.12.
 		Default is current version.
-	-largemodel
-		Generate code that assumes a large memory model.
 	-linkobj file
 		Write linker-specific object to file and compiler-specific
 		object to usual output file (as specified by -o).

src/cmd/compile/internal/gc/alg.go

@@ -186,6 +186,7 @@ func algtype1(t *types.Type) (AlgKind, *types.Type) {
 
 // genhash returns a symbol which is the closure used to compute
 // the hash of a value of type t.
+// Note: the generated function must match runtime.typehash exactly.
 func genhash(t *types.Type) *obj.LSym {
 	switch algtype(t) {
 	default:

src/cmd/compile/internal/gc/const.go

@@ -673,10 +673,6 @@ func evconst(n *Node) {
 		}
 
 	case OCOMPLEX:
-		if nl == nil || nr == nil {
-			// TODO(mdempsky): Remove after early OAS2FUNC rewrite CL lands.
-			break
-		}
 		if nl.Op == OLITERAL && nr.Op == OLITERAL {
 			// make it a complex literal
 			c := newMpcmplx()

src/cmd/compile/internal/gc/escape.go

@@ -1371,7 +1371,7 @@ func (e *Escape) finish(fns []*Node) {
 		fn.Esc = EscFuncTagged
 
 		narg := 0
-		for _, fs := range types.RecvsParams {
+		for _, fs := range &types.RecvsParams {
 			for _, f := range fs(fn.Type).Fields().Slice() {
 				narg++
 				f.Note = e.paramTag(fn, narg, f)

src/cmd/compile/internal/gc/fmt.go

@@ -585,28 +585,44 @@ s%^	........*\]%&~%g
 s%~	%%g
 */
 
-func symfmt(s *types.Sym, flag FmtFlag, mode fmtMode) string {
+func symfmt(b *bytes.Buffer, s *types.Sym, flag FmtFlag, mode fmtMode) {
 	if s.Pkg != nil && flag&FmtShort == 0 {
 		switch mode {
 		case FErr: // This is for the user
 			if s.Pkg == builtinpkg || s.Pkg == localpkg {
-				return s.Name
+				b.WriteString(s.Name)
+				return
 			}
 
 			// If the name was used by multiple packages, display the full path,
 			if s.Pkg.Name != "" && numImport[s.Pkg.Name] > 1 {
-				return fmt.Sprintf("%q.%s", s.Pkg.Path, s.Name)
+				fmt.Fprintf(b, "%q.%s", s.Pkg.Path, s.Name)
+				return
 			}
-			return s.Pkg.Name + "." + s.Name
+			b.WriteString(s.Pkg.Name)
+			b.WriteByte('.')
+			b.WriteString(s.Name)
+			return
 
 		case FDbg:
-			return s.Pkg.Name + "." + s.Name
+			b.WriteString(s.Pkg.Name)
+			b.WriteByte('.')
+			b.WriteString(s.Name)
+			return
 
 		case FTypeIdName:
-			return s.Pkg.Name + "." + s.Name // dcommontype, typehash
+			// dcommontype, typehash
+			b.WriteString(s.Pkg.Name)
+			b.WriteByte('.')
+			b.WriteString(s.Name)
+			return
 
 		case FTypeId:
-			return s.Pkg.Prefix + "." + s.Name // (methodsym), typesym, weaksym
+			// (methodsym), typesym, weaksym
+			b.WriteString(s.Pkg.Prefix)
+			b.WriteByte('.')
+			b.WriteString(s.Name)
+			return
 		}
 	}
 
@@ -619,13 +635,15 @@ func symfmt(s *types.Sym, flag FmtFlag, mode fmtMode) string {
 		}
 
 		if mode == FDbg {
-			return fmt.Sprintf("@%q.%s", s.Pkg.Path, name)
+			fmt.Fprintf(b, "@%q.%s", s.Pkg.Path, name)
+			return
 		}
 
-		return name
+		b.WriteString(name)
+		return
 	}
 
-	return s.Name
+	b.WriteString(s.Name)
 }
 
 var basicnames = []string{
@@ -652,16 +670,16 @@ var basicnames = []string{
 	TBLANK:      "blank",
 }
 
-var tconvBufferPool = sync.Pool{
+var fmtBufferPool = sync.Pool{
 	New: func() interface{} {
 		return new(bytes.Buffer)
 	},
 }
 
 func tconv(t *types.Type, flag FmtFlag, mode fmtMode) string {
-	buf := tconvBufferPool.Get().(*bytes.Buffer)
+	buf := fmtBufferPool.Get().(*bytes.Buffer)
 	buf.Reset()
-	defer tconvBufferPool.Put(buf)
+	defer fmtBufferPool.Put(buf)
 
 	tconv2(buf, t, flag, mode, nil)
 	return types.InternString(buf.Bytes())
@@ -703,7 +721,7 @@ func tconv2(b *bytes.Buffer, t *types.Type, flag FmtFlag, mode fmtMode, visited
 		case FTypeIdName, FTypeId:
 			t = types.Types[t.Etype]
 		default:
-			b.WriteString(sconv(t.Sym, FmtShort, mode))
+			sconv2(b, t.Sym, FmtShort, mode)
 			return
 		}
 	}
@@ -718,15 +736,16 @@ func tconv2(b *bytes.Buffer, t *types.Type, flag FmtFlag, mode fmtMode, visited
 		case FTypeId, FTypeIdName:
 			if flag&FmtShort != 0 {
 				if t.Vargen != 0 {
-					fmt.Fprintf(b, "%s·%d", sconv(t.Sym, FmtShort, mode), t.Vargen)
+					sconv2(b, t.Sym, FmtShort, mode)
+					fmt.Fprintf(b, "·%d", t.Vargen)
 					return
 				}
-				b.WriteString(sconv(t.Sym, FmtShort, mode))
+				sconv2(b, t.Sym, FmtShort, mode)
 				return
 			}
 
 			if mode == FTypeIdName {
-				b.WriteString(sconv(t.Sym, FmtUnsigned, mode))
+				sconv2(b, t.Sym, FmtUnsigned, mode)
 				return
 			}
 
@@ -736,7 +755,7 @@ func tconv2(b *bytes.Buffer, t *types.Type, flag FmtFlag, mode fmtMode, visited
 			}
 		}
 
-		b.WriteString(smodeString(t.Sym, mode))
+		sconv2(b, t.Sym, 0, mode)
 		return
 	}
 
@@ -845,13 +864,13 @@ func tconv2(b *bytes.Buffer, t *types.Type, flag FmtFlag, mode fmtMode, visited
 				// Wrong interface definitions may have types lacking a symbol.
 				break
 			case types.IsExported(f.Sym.Name):
-				b.WriteString(sconv(f.Sym, FmtShort, mode))
+				sconv2(b, f.Sym, FmtShort, mode)
 			default:
 				flag1 := FmtLeft
 				if flag&FmtUnsigned != 0 {
 					flag1 = FmtUnsigned
 				}
-				b.WriteString(sconv(f.Sym, flag1, mode))
+				sconv2(b, f.Sym, flag1, mode)
 			}
 			tconv2(b, f.Type, FmtShort, mode, visited)
 		}
@@ -941,7 +960,7 @@ func tconv2(b *bytes.Buffer, t *types.Type, flag FmtFlag, mode fmtMode, visited
 		b.WriteString("undefined")
 		if t.Sym != nil {
 			b.WriteByte(' ')
-			b.WriteString(smodeString(t.Sym, mode))
+			sconv2(b, t.Sym, 0, mode)
 		}
 
 	case TUNSAFEPTR:
@@ -1731,9 +1750,30 @@ func sconv(s *types.Sym, flag FmtFlag, mode fmtMode) string {
 	if s.Name == "_" {
 		return "_"
 	}
+	buf := fmtBufferPool.Get().(*bytes.Buffer)
+	buf.Reset()
+	defer fmtBufferPool.Put(buf)
 
 	flag, mode = flag.update(mode)
-	return symfmt(s, flag, mode)
+	symfmt(buf, s, flag, mode)
+	return types.InternString(buf.Bytes())
+}
+
+func sconv2(b *bytes.Buffer, s *types.Sym, flag FmtFlag, mode fmtMode) {
+	if flag&FmtLong != 0 {
+		panic("linksymfmt")
+	}
+	if s == nil {
+		b.WriteString("<S>")
+		return
+	}
+	if s.Name == "_" {
+		b.WriteString("_")
+		return
+	}
+
+	flag, mode = flag.update(mode)
+	symfmt(b, s, flag, mode)
 }
 
 func fldconv(b *bytes.Buffer, f *types.Field, flag FmtFlag, mode fmtMode, visited map[*types.Type]int, funarg types.Funarg) {

src/cmd/compile/internal/gc/iexport.go

@@ -954,7 +954,7 @@ func (w *exportWriter) funcExt(n *Node) {
 	w.symIdx(n.Sym)
 
 	// Escape analysis.
-	for _, fs := range types.RecvsParams {
+	for _, fs := range &types.RecvsParams {
 		for _, f := range fs(n.Type).FieldSlice() {
 			w.string(f.Note)
 		}

src/cmd/compile/internal/gc/iimport.go

@@ -660,7 +660,7 @@ func (r *importReader) funcExt(n *Node) {
 	r.symIdx(n.Sym)
 
 	// Escape analysis.
-	for _, fs := range types.RecvsParams {
+	for _, fs := range &types.RecvsParams {
 		for _, f := range fs(n.Type).FieldSlice() {
 			f.Note = r.string()
 		}

src/cmd/compile/internal/gc/main.go

@@ -1070,7 +1070,7 @@ func loadsys() {
 	typecheckok = true
 
 	typs := runtimeTypes()
-	for _, d := range runtimeDecls {
+	for _, d := range &runtimeDecls {
 		sym := Runtimepkg.Lookup(d.name)
 		typ := typs[d.typ]
 		switch d.tag {
@@ -1373,7 +1373,7 @@ var concurrentFlagOK = [256]bool{
 }
 
 func concurrentBackendAllowed() bool {
-	for i, x := range Debug {
+	for i, x := range &Debug {
 		if x != 0 && !concurrentFlagOK[i] {
 			return false
 		}

src/cmd/compile/internal/gc/noder.go

@@ -646,7 +646,7 @@ func (p *noder) expr(expr syntax.Expr) *Node {
 		}
 		n := p.nod(expr, op, p.expr(expr.X), nil)
 		var index [3]*Node
-		for i, x := range expr.Index {
+		for i, x := range &expr.Index {
 			if x != nil {
 				index[i] = p.expr(x)
 			}

src/cmd/compile/internal/gc/plive.go

@@ -419,7 +419,7 @@ func (lv *Liveness) regEffects(v *ssa.Value) (uevar, kill liveRegMask) {
 			if v.Type.Etype != types.TTUPLE {
 				v.Fatalf("location pair %s has non-tuple type %v", loc, v.Type)
 			}
-			for i, loc1 := range loc {
+			for i, loc1 := range &loc {
 				if loc1 == nil {
 					continue
 				}
@@ -705,12 +705,6 @@ func (lv *Liveness) markUnsafePoints() {
 					v = v.Args[0]
 					continue
 				}
-			case ssa.OpRISCV64SUBW:
-				// RISCV64 lowers Neq32 to include a SUBW with multiple arguments.
-				// TODO(jsing): it would be preferable not to use Neq32 for
-				// writeBuffer.enabled checks on this platform.
-				v = v.Args[0]
-				continue
 			case ssa.Op386MOVLload, ssa.OpARM64MOVWUload, ssa.OpPPC64MOVWZload, ssa.OpWasmI64Load32U:
 				// Args[0] is the address of the write
 				// barrier control. Ignore Args[1],

src/cmd/compile/internal/gc/ssa.go

@@ -3216,7 +3216,7 @@ func init() {
 	var p4 []*sys.Arch
 	var p8 []*sys.Arch
 	var lwatomics []*sys.Arch
-	for _, a := range sys.Archs {
+	for _, a := range &sys.Archs {
 		all = append(all, a)
 		if a.PtrSize == 4 {
 			p4 = append(p4, a)

src/cmd/compile/internal/gc/universe.go

@@ -66,7 +66,7 @@ var builtinFuncs = [...]struct {
 // isBuiltinFuncName reports whether name matches a builtin function
 // name.
 func isBuiltinFuncName(name string) bool {
-	for _, fn := range builtinFuncs {
+	for _, fn := range &builtinFuncs {
 		if fn.name == name {
 			return true
 		}
@@ -92,7 +92,7 @@ func initUniverse() {
 
 // lexinit initializes known symbols and the basic types.
 func lexinit() {
-	for _, s := range basicTypes {
+	for _, s := range &basicTypes {
 		etype := s.etype
 		if int(etype) >= len(types.Types) {
 			Fatalf("lexinit: %s bad etype", s.name)
@@ -111,13 +111,13 @@ func lexinit() {
 		asNode(s2.Def).Name = new(Name)
 	}
 
-	for _, s := range builtinFuncs {
+	for _, s := range &builtinFuncs {
 		s2 := builtinpkg.Lookup(s.name)
 		s2.Def = asTypesNode(newname(s2))
 		asNode(s2.Def).SetSubOp(s.op)
 	}
 
-	for _, s := range unsafeFuncs {
+	for _, s := range &unsafeFuncs {
 		s2 := unsafepkg.Lookup(s.name)
 		s2.Def = asTypesNode(newname(s2))
 		asNode(s2.Def).SetSubOp(s.op)
@@ -402,7 +402,7 @@ func lexinit1() {
 	dowidth(types.Runetype)
 
 	// backend-dependent builtin types (e.g. int).
-	for _, s := range typedefs {
+	for _, s := range &typedefs {
 		s1 := builtinpkg.Lookup(s.name)
 
 		sameas := s.sameas32

src/cmd/compile/internal/logopt/log_opts.go

@@ -390,7 +390,7 @@ func FlushLoggedOpts(ctxt *obj.Link, slashPkgPath string) {
 		var w io.WriteCloser
 
 		if slashPkgPath == "" {
-			slashPkgPath = string(0)
+			slashPkgPath = "\000"
 		}
 		subdirpath := filepath.Join(dest, pathEscape(slashPkgPath))
 		err := os.MkdirAll(subdirpath, 0755)

src/cmd/compile/internal/ssa/addressingmodes.go

@@ -0,0 +1,225 @@
+// Copyright 2020 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.
+
+package ssa
+
+// addressingModes combines address calculations into memory operations
+// that can perform complicated addressing modes.
+func addressingModes(f *Func) {
+	switch f.Config.arch {
+	default:
+		// Most architectures can't do this.
+		return
+	case "amd64", "386":
+		// TODO: s390x?
+	}
+
+	var tmp []*Value
+	for _, b := range f.Blocks {
+		for _, v := range b.Values {
+			if !combineFirst[v.Op] {
+				continue
+			}
+			// All matched operations have the pointer in arg[0].
+			// All results have the pointer in arg[0] and the index in arg[1].
+			// *Except* for operations which update a register,
+			// which are marked with resultInArg0. Those have
+			// the pointer in arg[1], and the corresponding result op
+			// has the pointer in arg[1] and the index in arg[2].
+			ptrIndex := 0
+			if opcodeTable[v.Op].resultInArg0 {
+				ptrIndex = 1
+			}
+			p := v.Args[ptrIndex]
+			c, ok := combine[[2]Op{v.Op, p.Op}]
+			if !ok {
+				continue
+			}
+			// See if we can combine the Aux/AuxInt values.
+			switch [2]auxType{opcodeTable[v.Op].auxType, opcodeTable[p.Op].auxType} {
+			case [2]auxType{auxSymOff, auxInt32}:
+				// TODO: introduce auxSymOff32
+				if !is32Bit(v.AuxInt + p.AuxInt) {
+					continue
+				}
+				v.AuxInt += p.AuxInt
+			case [2]auxType{auxSymOff, auxSymOff}:
+				if v.Aux != nil && p.Aux != nil {
+					continue
+				}
+				if !is32Bit(v.AuxInt + p.AuxInt) {
+					continue
+				}
+				if p.Aux != nil {
+					v.Aux = p.Aux
+				}
+				v.AuxInt += p.AuxInt
+			case [2]auxType{auxSymValAndOff, auxInt32}:
+				vo := ValAndOff(v.AuxInt)
+				if !vo.canAdd(p.AuxInt) {
+					continue
+				}
+				v.AuxInt = vo.add(p.AuxInt)
+			case [2]auxType{auxSymValAndOff, auxSymOff}:
+				vo := ValAndOff(v.AuxInt)
+				if v.Aux != nil && p.Aux != nil {
+					continue
+				}
+				if !vo.canAdd(p.AuxInt) {
+					continue
+				}
+				if p.Aux != nil {
+					v.Aux = p.Aux
+				}
+				v.AuxInt = vo.add(p.AuxInt)
+			case [2]auxType{auxSymOff, auxNone}:
+				// nothing to do
+			case [2]auxType{auxSymValAndOff, auxNone}:
+				// nothing to do
+			default:
+				f.Fatalf("unknown aux combining for %s and %s\n", v.Op, p.Op)
+			}
+			// Combine the operations.
+			tmp = append(tmp[:0], v.Args[:ptrIndex]...)
+			tmp = append(tmp, p.Args...)
+			tmp = append(tmp, v.Args[ptrIndex+1:]...)
+			v.resetArgs()
+			v.Op = c
+			v.AddArgs(tmp...)
+		}
+	}
+}
+
+// combineFirst contains ops which appear in combine as the
+// first part of the key.
+var combineFirst = map[Op]bool{}
+
+func init() {
+	for k := range combine {
+		combineFirst[k[0]] = true
+	}
+}
+
+// For each entry k, v in this map, if we have a value x with:
+//   x.Op == k[0]
+//   x.Args[0].Op == k[1]
+// then we can set x.Op to v and set x.Args like this:
+//   x.Args[0].Args + x.Args[1:]
+// Additionally, the Aux/AuxInt from x.Args[0] is merged into x.
+var combine = map[[2]Op]Op{
+	// amd64
+	[2]Op{OpAMD64MOVBload, OpAMD64ADDQ}:  OpAMD64MOVBloadidx1,
+	[2]Op{OpAMD64MOVWload, OpAMD64ADDQ}:  OpAMD64MOVWloadidx1,
+	[2]Op{OpAMD64MOVLload, OpAMD64ADDQ}:  OpAMD64MOVLloadidx1,
+	[2]Op{OpAMD64MOVQload, OpAMD64ADDQ}:  OpAMD64MOVQloadidx1,
+	[2]Op{OpAMD64MOVSSload, OpAMD64ADDQ}: OpAMD64MOVSSloadidx1,
+	[2]Op{OpAMD64MOVSDload, OpAMD64ADDQ}: OpAMD64MOVSDloadidx1,
+
+	[2]Op{OpAMD64MOVBstore, OpAMD64ADDQ}:  OpAMD64MOVBstoreidx1,
+	[2]Op{OpAMD64MOVWstore, OpAMD64ADDQ}:  OpAMD64MOVWstoreidx1,
+	[2]Op{OpAMD64MOVLstore, OpAMD64ADDQ}:  OpAMD64MOVLstoreidx1,
+	[2]Op{OpAMD64MOVQstore, OpAMD64ADDQ}:  OpAMD64MOVQstoreidx1,
+	[2]Op{OpAMD64MOVSSstore, OpAMD64ADDQ}: OpAMD64MOVSSstoreidx1,
+	[2]Op{OpAMD64MOVSDstore, OpAMD64ADDQ}: OpAMD64MOVSDstoreidx1,
+
+	[2]Op{OpAMD64MOVBstoreconst, OpAMD64ADDQ}: OpAMD64MOVBstoreconstidx1,
+	[2]Op{OpAMD64MOVWstoreconst, OpAMD64ADDQ}: OpAMD64MOVWstoreconstidx1,
+	[2]Op{OpAMD64MOVLstoreconst, OpAMD64ADDQ}: OpAMD64MOVLstoreconstidx1,
+	[2]Op{OpAMD64MOVQstoreconst, OpAMD64ADDQ}: OpAMD64MOVQstoreconstidx1,
+
+	[2]Op{OpAMD64MOVBload, OpAMD64LEAQ1}:  OpAMD64MOVBloadidx1,
+	[2]Op{OpAMD64MOVWload, OpAMD64LEAQ1}:  OpAMD64MOVWloadidx1,
+	[2]Op{OpAMD64MOVWload, OpAMD64LEAQ2}:  OpAMD64MOVWloadidx2,
+	[2]Op{OpAMD64MOVLload, OpAMD64LEAQ1}:  OpAMD64MOVLloadidx1,
+	[2]Op{OpAMD64MOVLload, OpAMD64LEAQ4}:  OpAMD64MOVLloadidx4,
+	[2]Op{OpAMD64MOVLload, OpAMD64LEAQ8}:  OpAMD64MOVLloadidx8,
+	[2]Op{OpAMD64MOVQload, OpAMD64LEAQ1}:  OpAMD64MOVQloadidx1,
+	[2]Op{OpAMD64MOVQload, OpAMD64LEAQ8}:  OpAMD64MOVQloadidx8,
+	[2]Op{OpAMD64MOVSSload, OpAMD64LEAQ1}: OpAMD64MOVSSloadidx1,
+	[2]Op{OpAMD64MOVSSload, OpAMD64LEAQ4}: OpAMD64MOVSSloadidx4,
+	[2]Op{OpAMD64MOVSDload, OpAMD64LEAQ1}: OpAMD64MOVSDloadidx1,
+	[2]Op{OpAMD64MOVSDload, OpAMD64LEAQ8}: OpAMD64MOVSDloadidx8,
+
+	[2]Op{OpAMD64MOVBstore, OpAMD64LEAQ1}:  OpAMD64MOVBstoreidx1,
+	[2]Op{OpAMD64MOVWstore, OpAMD64LEAQ1}:  OpAMD64MOVWstoreidx1,
+	[2]Op{OpAMD64MOVWstore, OpAMD64LEAQ2}:  OpAMD64MOVWstoreidx2,
+	[2]Op{OpAMD64MOVLstore, OpAMD64LEAQ1}:  OpAMD64MOVLstoreidx1,
+	[2]Op{OpAMD64MOVLstore, OpAMD64LEAQ4}:  OpAMD64MOVLstoreidx4,
+	[2]Op{OpAMD64MOVLstore, OpAMD64LEAQ8}:  OpAMD64MOVLstoreidx8,
+	[2]Op{OpAMD64MOVQstore, OpAMD64LEAQ1}:  OpAMD64MOVQstoreidx1,
+	[2]Op{OpAMD64MOVQstore, OpAMD64LEAQ8}:  OpAMD64MOVQstoreidx8,
+	[2]Op{OpAMD64MOVSSstore, OpAMD64LEAQ1}: OpAMD64MOVSSstoreidx1,
+	[2]Op{OpAMD64MOVSSstore, OpAMD64LEAQ4}: OpAMD64MOVSSstoreidx4,
+	[2]Op{OpAMD64MOVSDstore, OpAMD64LEAQ1}: OpAMD64MOVSDstoreidx1,
+	[2]Op{OpAMD64MOVSDstore, OpAMD64LEAQ8}: OpAMD64MOVSDstoreidx8,
+
+	[2]Op{OpAMD64MOVBstoreconst, OpAMD64LEAQ1}: OpAMD64MOVBstoreconstidx1,
+	[2]Op{OpAMD64MOVWstoreconst, OpAMD64LEAQ1}: OpAMD64MOVWstoreconstidx1,
+	[2]Op{OpAMD64MOVWstoreconst, OpAMD64LEAQ2}: OpAMD64MOVWstoreconstidx2,
+	[2]Op{OpAMD64MOVLstoreconst, OpAMD64LEAQ1}: OpAMD64MOVLstoreconstidx1,
+	[2]Op{OpAMD64MOVLstoreconst, OpAMD64LEAQ4}: OpAMD64MOVLstoreconstidx4,
+	[2]Op{OpAMD64MOVQstoreconst, OpAMD64LEAQ1}: OpAMD64MOVQstoreconstidx1,
+	[2]Op{OpAMD64MOVQstoreconst, OpAMD64LEAQ8}: OpAMD64MOVQstoreconstidx8,
+
+	// 386
+	[2]Op{Op386MOVBload, Op386ADDL}:  Op386MOVBloadidx1,
+	[2]Op{Op386MOVWload, Op386ADDL}:  Op386MOVWloadidx1,
+	[2]Op{Op386MOVLload, Op386ADDL}:  Op386MOVLloadidx1,
+	[2]Op{Op386MOVSSload, Op386ADDL}: Op386MOVSSloadidx1,
+	[2]Op{Op386MOVSDload, Op386ADDL}: Op386MOVSDloadidx1,
+
+	[2]Op{Op386MOVBstore, Op386ADDL}:  Op386MOVBstoreidx1,
+	[2]Op{Op386MOVWstore, Op386ADDL}:  Op386MOVWstoreidx1,
+	[2]Op{Op386MOVLstore, Op386ADDL}:  Op386MOVLstoreidx1,
+	[2]Op{Op386MOVSSstore, Op386ADDL}: Op386MOVSSstoreidx1,
+	[2]Op{Op386MOVSDstore, Op386ADDL}: Op386MOVSDstoreidx1,
+
+	[2]Op{Op386MOVBstoreconst, Op386ADDL}: Op386MOVBstoreconstidx1,
+	[2]Op{Op386MOVWstoreconst, Op386ADDL}: Op386MOVWstoreconstidx1,
+	[2]Op{Op386MOVLstoreconst, Op386ADDL}: Op386MOVLstoreconstidx1,
+
+	[2]Op{Op386MOVBload, Op386LEAL1}:  Op386MOVBloadidx1,
+	[2]Op{Op386MOVWload, Op386LEAL1}:  Op386MOVWloadidx1,
+	[2]Op{Op386MOVWload, Op386LEAL2}:  Op386MOVWloadidx2,
+	[2]Op{Op386MOVLload, Op386LEAL1}:  Op386MOVLloadidx1,
+	[2]Op{Op386MOVLload, Op386LEAL4}:  Op386MOVLloadidx4,
+	[2]Op{Op386MOVSSload, Op386LEAL1}: Op386MOVSSloadidx1,
+	[2]Op{Op386MOVSSload, Op386LEAL4}: Op386MOVSSloadidx4,
+	[2]Op{Op386MOVSDload, Op386LEAL1}: Op386MOVSDloadidx1,
+	[2]Op{Op386MOVSDload, Op386LEAL8}: Op386MOVSDloadidx8,
+
+	[2]Op{Op386MOVBstore, Op386LEAL1}:  Op386MOVBstoreidx1,
+	[2]Op{Op386MOVWstore, Op386LEAL1}:  Op386MOVWstoreidx1,
+	[2]Op{Op386MOVWstore, Op386LEAL2}:  Op386MOVWstoreidx2,
+	[2]Op{Op386MOVLstore, Op386LEAL1}:  Op386MOVLstoreidx1,
+	[2]Op{Op386MOVLstore, Op386LEAL4}:  Op386MOVLstoreidx4,
+	[2]Op{Op386MOVSSstore, Op386LEAL1}: Op386MOVSSstoreidx1,
+	[2]Op{Op386MOVSSstore, Op386LEAL4}: Op386MOVSSstoreidx4,
+	[2]Op{Op386MOVSDstore, Op386LEAL1}: Op386MOVSDstoreidx1,
+	[2]Op{Op386MOVSDstore, Op386LEAL8}: Op386MOVSDstoreidx8,
+
+	[2]Op{Op386MOVBstoreconst, Op386LEAL1}: Op386MOVBstoreconstidx1,
+	[2]Op{Op386MOVWstoreconst, Op386LEAL1}: Op386MOVWstoreconstidx1,
+	[2]Op{Op386MOVWstoreconst, Op386LEAL2}: Op386MOVWstoreconstidx2,
+	[2]Op{Op386MOVLstoreconst, Op386LEAL1}: Op386MOVLstoreconstidx1,
+	[2]Op{Op386MOVLstoreconst, Op386LEAL4}: Op386MOVLstoreconstidx4,
+
+	[2]Op{Op386ADDLload, Op386LEAL4}: Op386ADDLloadidx4,
+	[2]Op{Op386SUBLload, Op386LEAL4}: Op386SUBLloadidx4,
+	[2]Op{Op386MULLload, Op386LEAL4}: Op386MULLloadidx4,
+	[2]Op{Op386ANDLload, Op386LEAL4}: Op386ANDLloadidx4,
+	[2]Op{Op386ORLload, Op386LEAL4}:  Op386ORLloadidx4,
+	[2]Op{Op386XORLload, Op386LEAL4}: Op386XORLloadidx4,
+
+	[2]Op{Op386ADDLmodify, Op386LEAL4}: Op386ADDLmodifyidx4,
+	[2]Op{Op386SUBLmodify, Op386LEAL4}: Op386SUBLmodifyidx4,
+	[2]Op{Op386ANDLmodify, Op386LEAL4}: Op386ANDLmodifyidx4,
+	[2]Op{Op386ORLmodify, Op386LEAL4}:  Op386ORLmodifyidx4,
+	[2]Op{Op386XORLmodify, Op386LEAL4}: Op386XORLmodifyidx4,
+
+	[2]Op{Op386ADDLconstmodify, Op386LEAL4}: Op386ADDLconstmodifyidx4,
+	[2]Op{Op386ANDLconstmodify, Op386LEAL4}: Op386ANDLconstmodifyidx4,
+	[2]Op{Op386ORLconstmodify, Op386LEAL4}:  Op386ORLconstmodifyidx4,
+	[2]Op{Op386XORLconstmodify, Op386LEAL4}: Op386XORLconstmodifyidx4,
+}

src/cmd/compile/internal/ssa/block.go

@@ -101,6 +101,9 @@ func (e Edge) Block() *Block {
 func (e Edge) Index() int {
 	return e.i
 }
+func (e Edge) String() string {
+	return fmt.Sprintf("{%v,%d}", e.b, e.i)
+}
 
 //     kind          controls        successors
 //   ------------------------------------------

src/cmd/compile/internal/ssa/compile.go

@@ -442,6 +442,7 @@ var passes = [...]pass{
 	{name: "insert resched checks", fn: insertLoopReschedChecks,
 		disabled: objabi.Preemptibleloops_enabled == 0}, // insert resched checks in loops.
 	{name: "lower", fn: lower, required: true},
+	{name: "addressing modes", fn: addressingModes, required: false},
 	{name: "lowered deadcode for cse", fn: deadcode}, // deadcode immediately before CSE avoids CSE making dead values live again
 	{name: "lowered cse", fn: cse},
 	{name: "elim unread autos", fn: elimUnreadAutos},

src/cmd/compile/internal/ssa/gen/386.rules

@@ -588,10 +588,6 @@
 (MOVWLSX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWLSXload <v.Type> [off] {sym} ptr mem)
 (MOVWLZX x:(MOVWload [off] {sym} ptr mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWload <v.Type> [off] {sym} ptr mem)
 
-(MOVBLZX x:(MOVBloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVBloadidx1 <v.Type> [off] {sym} ptr idx mem)
-(MOVWLZX x:(MOVWloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWloadidx1 <v.Type> [off] {sym} ptr idx mem)
-(MOVWLZX x:(MOVWloadidx2 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWloadidx2 <v.Type> [off] {sym} ptr idx mem)
-
 // replace load from same location as preceding store with zero/sign extension (or copy in case of full width)
 (MOVBload [off] {sym} ptr (MOVBstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> (MOVBLZX x)
 (MOVWload [off] {sym} ptr (MOVWstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> (MOVWLZX x)
@@ -611,34 +607,22 @@
 
 // fold constants into memory operations
 // Note that this is not always a good idea because if not all the uses of
-// the ADDQconst get eliminated, we still have to compute the ADDQconst and we now
-// have potentially two live values (ptr and (ADDQconst [off] ptr)) instead of one.
+// the ADDLconst get eliminated, we still have to compute the ADDLconst and we now
+// have potentially two live values (ptr and (ADDLconst [off] ptr)) instead of one.
 // Nevertheless, let's do it!
 (MOV(L|W|B|SS|SD)load  [off1] {sym} (ADDLconst [off2] ptr) mem) && is32Bit(off1+off2) -> (MOV(L|W|B|SS|SD)load  [off1+off2] {sym} ptr mem)
 (MOV(L|W|B|SS|SD)store  [off1] {sym} (ADDLconst [off2] ptr) val mem) && is32Bit(off1+off2) -> (MOV(L|W|B|SS|SD)store  [off1+off2] {sym} ptr val mem)
 
 ((ADD|SUB|MUL|AND|OR|XOR)Lload [off1] {sym} val (ADDLconst [off2] base) mem) && is32Bit(off1+off2) ->
 	((ADD|SUB|MUL|AND|OR|XOR)Lload [off1+off2] {sym} val base mem)
-((ADD|SUB|MUL|AND|OR|XOR)Lloadidx4 [off1] {sym} val (ADDLconst [off2] base) idx mem) && is32Bit(off1+off2) ->
-	((ADD|SUB|MUL|AND|OR|XOR)Lloadidx4 [off1+off2] {sym} val base idx mem)
-((ADD|SUB|MUL|AND|OR|XOR)Lloadidx4 [off1] {sym} val base (ADDLconst [off2] idx) mem) && is32Bit(off1+off2*4) ->
-	((ADD|SUB|MUL|AND|OR|XOR)Lloadidx4 [off1+off2*4] {sym} val base idx mem)
 ((ADD|SUB|MUL|DIV)SSload [off1] {sym} val (ADDLconst [off2] base) mem) && is32Bit(off1+off2) ->
 	((ADD|SUB|MUL|DIV)SSload [off1+off2] {sym} val base mem)
 ((ADD|SUB|MUL|DIV)SDload [off1] {sym} val (ADDLconst [off2] base) mem) && is32Bit(off1+off2) ->
 	((ADD|SUB|MUL|DIV)SDload [off1+off2] {sym} val base mem)
 ((ADD|SUB|AND|OR|XOR)Lmodify [off1] {sym} (ADDLconst [off2] base) val mem) && is32Bit(off1+off2) ->
 	((ADD|SUB|AND|OR|XOR)Lmodify [off1+off2] {sym} base val mem)
-((ADD|SUB|AND|OR|XOR)Lmodifyidx4 [off1] {sym} (ADDLconst [off2] base) idx val mem) && is32Bit(off1+off2) ->
-	((ADD|SUB|AND|OR|XOR)Lmodifyidx4 [off1+off2] {sym} base idx val mem)
-((ADD|SUB|AND|OR|XOR)Lmodifyidx4 [off1] {sym} base (ADDLconst [off2] idx) val mem) && is32Bit(off1+off2*4) ->
-	((ADD|SUB|AND|OR|XOR)Lmodifyidx4 [off1+off2*4] {sym} base idx val mem)
 ((ADD|AND|OR|XOR)Lconstmodify [valoff1] {sym} (ADDLconst [off2] base) mem) && ValAndOff(valoff1).canAdd(off2) ->
 	((ADD|AND|OR|XOR)Lconstmodify [ValAndOff(valoff1).add(off2)] {sym} base mem)
-((ADD|AND|OR|XOR)Lconstmodifyidx4 [valoff1] {sym} (ADDLconst [off2] base) idx mem) && ValAndOff(valoff1).canAdd(off2) ->
-	((ADD|AND|OR|XOR)Lconstmodifyidx4 [ValAndOff(valoff1).add(off2)] {sym} base idx mem)
-((ADD|AND|OR|XOR)Lconstmodifyidx4 [valoff1] {sym} base (ADDLconst [off2] idx) mem) && ValAndOff(valoff1).canAdd(off2*4) ->
-	((ADD|AND|OR|XOR)Lconstmodifyidx4 [ValAndOff(valoff1).add(off2*4)] {sym} base idx mem)
 
 // Fold constants into stores.
 (MOVLstore [off] {sym} ptr (MOVLconst [c]) mem) && validOff(off) ->
@@ -652,7 +636,7 @@
 (MOV(L|W|B)storeconst [sc] {s} (ADDLconst [off] ptr) mem) && ValAndOff(sc).canAdd(off) ->
 	(MOV(L|W|B)storeconst [ValAndOff(sc).add(off)] {s} ptr mem)
 
-// We need to fold LEAQ into the MOVx ops so that the live variable analysis knows
+// We need to fold LEAL into the MOVx ops so that the live variable analysis knows
 // what variables are being read/written by the ops.
 // Note: we turn off this merging for operations on globals when building
 // position-independent code (when Flag_shared is set).
@@ -672,31 +656,9 @@
   && (ptr.Op != OpSB || !config.ctxt.Flag_shared) ->
 	(MOV(L|W|B)storeconst [ValAndOff(sc).add(off)] {mergeSym(sym1, sym2)} ptr mem)
 
-// generating indexed loads and stores
-(MOV(B|W|L|SS|SD)load [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(B|W|L|SS|SD)loadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOVWload [off1] {sym1} (LEAL2 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOVWloadidx2 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOV(L|SS)load [off1] {sym1} (LEAL4 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(L|SS)loadidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOVSDload [off1] {sym1} (LEAL8 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOVSDloadidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
-
-(MOV(B|W|L|SS|SD)store [off1] {sym1} (LEAL1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(B|W|L|SS|SD)storeidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
-(MOVWstore [off1] {sym1} (LEAL2 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOVWstoreidx2 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
-(MOV(L|SS)store [off1] {sym1} (LEAL4 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(L|SS)storeidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
-(MOVSDstore [off1] {sym1} (LEAL8 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOVSDstoreidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
-
 ((ADD|SUB|MUL|AND|OR|XOR)Lload [off1] {sym1} val (LEAL [off2] {sym2} base) mem)
 	&& is32Bit(off1+off2) && canMergeSym(sym1, sym2) && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
 	((ADD|SUB|MUL|AND|OR|XOR)Lload [off1+off2] {mergeSym(sym1,sym2)} val base mem)
-((ADD|SUB|MUL|AND|OR|XOR)Lloadidx4 [off1] {sym1} val (LEAL [off2] {sym2} base) idx mem)
-	&& is32Bit(off1+off2) && canMergeSym(sym1, sym2) && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
-	((ADD|SUB|MUL|AND|OR|XOR)Lloadidx4 [off1+off2] {mergeSym(sym1,sym2)} val base idx mem)
 ((ADD|SUB|MUL|DIV)SSload [off1] {sym1} val (LEAL [off2] {sym2} base) mem)
 	&& is32Bit(off1+off2) && canMergeSym(sym1, sym2) && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
 	((ADD|SUB|MUL|DIV)SSload [off1+off2] {mergeSym(sym1,sym2)} val base mem)
@@ -706,97 +668,20 @@
 ((ADD|SUB|AND|OR|XOR)Lmodify [off1] {sym1} (LEAL [off2] {sym2} base) val mem)
 	&& is32Bit(off1+off2) && canMergeSym(sym1, sym2) && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
 	((ADD|SUB|AND|OR|XOR)Lmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem)
-((ADD|SUB|AND|OR|XOR)Lmodifyidx4 [off1] {sym1} (LEAL [off2] {sym2} base) idx val mem)
-	&& is32Bit(off1+off2) && canMergeSym(sym1, sym2) && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
-	((ADD|SUB|AND|OR|XOR)Lmodifyidx4 [off1+off2] {mergeSym(sym1,sym2)} base idx val mem)
 ((ADD|AND|OR|XOR)Lconstmodify [valoff1] {sym1} (LEAL [off2] {sym2} base) mem)
 	&& ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
 	((ADD|AND|OR|XOR)Lconstmodify [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base mem)
-((ADD|AND|OR|XOR)Lconstmodifyidx4 [valoff1] {sym1} (LEAL [off2] {sym2} base) idx mem)
-	&& ValAndOff(valoff1).canAdd(off2) && canMergeSym(sym1, sym2) && (base.Op != OpSB || !config.ctxt.Flag_shared) ->
-	((ADD|AND|OR|XOR)Lconstmodifyidx4 [ValAndOff(valoff1).add(off2)] {mergeSym(sym1,sym2)} base idx mem)
-
-(MOV(B|W|L|SS|SD)load [off] {sym} (ADDL ptr idx) mem) && ptr.Op != OpSB -> (MOV(B|W|L|SS|SD)loadidx1 [off] {sym} ptr idx mem)
-(MOV(B|W|L|SS|SD)store [off] {sym} (ADDL ptr idx) val mem) && ptr.Op != OpSB -> (MOV(B|W|L|SS|SD)storeidx1 [off] {sym} ptr idx val mem)
-
-(MOV(B|W|L)storeconst [x] {sym1} (LEAL1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
-	(MOV(B|W|L)storeconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOVWstoreconst [x] {sym1} (LEAL2 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
-	(MOVWstoreconstidx2 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOVLstoreconst [x] {sym1} (LEAL4 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
-	(MOVLstoreconstidx4 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
-
-(MOV(B|W|L)storeconst [x] {sym} (ADDL ptr idx) mem) -> (MOV(B|W|L)storeconstidx1 [x] {sym} ptr idx mem)
-
-// combine SHLL into indexed loads and stores
-(MOVWloadidx1 [c] {sym} ptr (SHLLconst [1] idx) mem) -> (MOVWloadidx2 [c] {sym} ptr idx mem)
-(MOVLloadidx1 [c] {sym} ptr (SHLLconst [2] idx) mem) -> (MOVLloadidx4 [c] {sym} ptr idx mem)
-(MOVWstoreidx1 [c] {sym} ptr (SHLLconst [1] idx) val mem) -> (MOVWstoreidx2 [c] {sym} ptr idx val mem)
-(MOVLstoreidx1 [c] {sym} ptr (SHLLconst [2] idx) val mem) -> (MOVLstoreidx4 [c] {sym} ptr idx val mem)
-(MOVWstoreconstidx1 [c] {sym} ptr (SHLLconst [1] idx) mem) -> (MOVWstoreconstidx2 [c] {sym} ptr idx mem)
-(MOVLstoreconstidx1 [c] {sym} ptr (SHLLconst [2] idx) mem) -> (MOVLstoreconstidx4 [c] {sym} ptr idx mem)
-
-// combine ADDL into indexed loads and stores
-(MOV(B|W|L|SS|SD)loadidx1 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOV(B|W|L|SS|SD)loadidx1 [int64(int32(c+d))] {sym} ptr idx mem)
-(MOVWloadidx2 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVWloadidx2 [int64(int32(c+d))] {sym} ptr idx mem)
-(MOV(L|SS)loadidx4 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOV(L|SS)loadidx4 [int64(int32(c+d))] {sym} ptr idx mem)
-(MOVSDloadidx8 [c] {sym} (ADDLconst [d] ptr) idx mem) -> (MOVSDloadidx8 [int64(int32(c+d))] {sym} ptr idx mem)
-
-(MOV(B|W|L|SS|SD)storeidx1 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOV(B|W|L|SS|SD)storeidx1 [int64(int32(c+d))] {sym} ptr idx val mem)
-(MOVWstoreidx2 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVWstoreidx2 [int64(int32(c+d))] {sym} ptr idx val mem)
-(MOV(L|SS)storeidx4 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOV(L|SS)storeidx4 [int64(int32(c+d))] {sym} ptr idx val mem)
-(MOVSDstoreidx8 [c] {sym} (ADDLconst [d] ptr) idx val mem) -> (MOVSDstoreidx8 [int64(int32(c+d))] {sym} ptr idx val mem)
-
-(MOV(B|W|L|SS|SD)loadidx1 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOV(B|W|L|SS|SD)loadidx1 [int64(int32(c+d))] {sym} ptr idx mem)
-(MOVWloadidx2 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVWloadidx2 [int64(int32(c+2*d))] {sym} ptr idx mem)
-(MOV(L|SS)loadidx4 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOV(L|SS)loadidx4 [int64(int32(c+4*d))] {sym} ptr idx mem)
-(MOVSDloadidx8 [c] {sym} ptr (ADDLconst [d] idx) mem) -> (MOVSDloadidx8 [int64(int32(c+8*d))] {sym} ptr idx mem)
-
-(MOV(B|W|L|SS|SD)storeidx1 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOV(B|W|L|SS|SD)storeidx1  [int64(int32(c+d))]   {sym} ptr idx val mem)
-(MOVWstoreidx2 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVWstoreidx2  [int64(int32(c+2*d))] {sym} ptr idx val mem)
-(MOV(L|SS)storeidx4 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOV(L|SS)storeidx4 [int64(int32(c+4*d))] {sym} ptr idx val mem)
-(MOVSDstoreidx8 [c] {sym} ptr (ADDLconst [d] idx) val mem) -> (MOVSDstoreidx8 [int64(int32(c+8*d))] {sym} ptr idx val mem)
 
 // Merge load/store to op
 ((ADD|AND|OR|XOR|SUB|MUL)L x l:(MOVLload [off] {sym} ptr mem)) && canMergeLoadClobber(v, l, x) && clobber(l) -> ((ADD|AND|OR|XOR|SUB|MUL)Lload x [off] {sym} ptr mem)
-((ADD|AND|OR|XOR|SUB|MUL)L x l:(MOVLloadidx4 [off] {sym} ptr idx mem)) && canMergeLoadClobber(v, l, x) && clobber(l) ->
-	((ADD|AND|OR|XOR|SUB|MUL)Lloadidx4 x [off] {sym} ptr idx mem)
-((ADD|SUB|MUL|AND|OR|XOR)Lload [off1] {sym1} val (LEAL4 [off2] {sym2} ptr idx) mem)
-	&& is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	((ADD|SUB|MUL|AND|OR|XOR)Lloadidx4 [off1+off2] {mergeSym(sym1,sym2)} val ptr idx mem)
 ((ADD|SUB|MUL|DIV)SD x l:(MOVSDload [off] {sym} ptr mem)) && canMergeLoadClobber(v, l, x) && !config.use387 && clobber(l) -> ((ADD|SUB|MUL|DIV)SDload x [off] {sym} ptr mem)
 ((ADD|SUB|MUL|DIV)SS x l:(MOVSSload [off] {sym} ptr mem)) && canMergeLoadClobber(v, l, x) && !config.use387 && clobber(l) -> ((ADD|SUB|MUL|DIV)SSload x [off] {sym} ptr mem)
 (MOVLstore {sym} [off] ptr y:((ADD|AND|OR|XOR)Lload x [off] {sym} ptr mem) mem) && y.Uses==1 && clobber(y) -> ((ADD|AND|OR|XOR)Lmodify [off] {sym} ptr x mem)
 (MOVLstore {sym} [off] ptr y:((ADD|SUB|AND|OR|XOR)L l:(MOVLload [off] {sym} ptr mem) x) mem) && y.Uses==1 && l.Uses==1 && clobber(y, l) ->
 	((ADD|SUB|AND|OR|XOR)Lmodify [off] {sym} ptr x mem)
-(MOVLstoreidx4 {sym} [off] ptr idx y:((ADD|AND|OR|XOR)Lloadidx4 x [off] {sym} ptr idx mem) mem) && y.Uses==1 && clobber(y) ->
-	((ADD|AND|OR|XOR)Lmodifyidx4 [off] {sym} ptr idx x mem)
-(MOVLstoreidx4 {sym} [off] ptr idx y:((ADD|SUB|AND|OR|XOR)L l:(MOVLloadidx4 [off] {sym} ptr idx mem) x) mem) && y.Uses==1 && l.Uses==1 && clobber(y, l) ->
-	((ADD|SUB|AND|OR|XOR)Lmodifyidx4 [off] {sym} ptr idx x mem)
 (MOVLstore {sym} [off] ptr y:((ADD|AND|OR|XOR)Lconst [c] l:(MOVLload [off] {sym} ptr mem)) mem)
 	&& y.Uses==1 && l.Uses==1 && clobber(y, l) && validValAndOff(c,off) ->
 	((ADD|AND|OR|XOR)Lconstmodify [makeValAndOff(c,off)] {sym} ptr mem)
-(MOVLstoreidx4 {sym} [off] ptr idx y:((ADD|AND|OR|XOR)Lconst [c] l:(MOVLloadidx4 [off] {sym} ptr idx mem)) mem)
-	&& y.Uses==1 && l.Uses==1 && clobber(y, l) && validValAndOff(c,off) ->
-	((ADD|AND|OR|XOR)Lconstmodifyidx4 [makeValAndOff(c,off)] {sym} ptr idx mem)
-((ADD|AND|OR|XOR)Lmodifyidx4 [off] {sym} ptr idx (MOVLconst [c]) mem) && validValAndOff(c,off) ->
-	((ADD|AND|OR|XOR)Lconstmodifyidx4 [makeValAndOff(c,off)] {sym} ptr idx mem)
-(SUBLmodifyidx4 [off] {sym} ptr idx (MOVLconst [c]) mem) && validValAndOff(-c,off) ->
-	(ADDLconstmodifyidx4 [makeValAndOff(-c,off)] {sym} ptr idx mem)
-
-(MOV(B|W|L)storeconstidx1 [x] {sym} (ADDLconst [c] ptr) idx mem) ->
-	(MOV(B|W|L)storeconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-(MOVWstoreconstidx2 [x] {sym} (ADDLconst [c] ptr) idx mem) ->
-	(MOVWstoreconstidx2 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-(MOVLstoreconstidx4 [x] {sym} (ADDLconst [c] ptr) idx mem) ->
-	(MOVLstoreconstidx4 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-
-(MOV(B|W|L)storeconstidx1 [x] {sym} ptr (ADDLconst [c] idx) mem) ->
-	(MOV(B|W|L)storeconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-(MOVWstoreconstidx2 [x] {sym} ptr (ADDLconst [c] idx) mem) ->
-	(MOVWstoreconstidx2 [ValAndOff(x).add(2*c)] {sym} ptr idx mem)
-(MOVLstoreconstidx4 [x] {sym} ptr (ADDLconst [c] idx) mem) ->
-	(MOVLstoreconstidx4 [ValAndOff(x).add(4*c)] {sym} ptr idx mem)
 
 // fold LEALs together
 (LEAL [off1] {sym1} (LEAL [off2] {sym2} x)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
@@ -826,6 +711,16 @@
 (LEAL [off1] {sym1} (LEAL8 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
       (LEAL8 [off1+off2] {mergeSym(sym1,sym2)} x y)
 
+// LEAL[1248] into LEAL[1248]. Only some such merges are possible.
+(LEAL1 [off1] {sym1} x (LEAL1 [off2] {sym2} y y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
+      (LEAL2 [off1+off2] {mergeSym(sym1, sym2)} x y)
+(LEAL1 [off1] {sym1} x (LEAL1 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
+      (LEAL2 [off1+off2] {mergeSym(sym1, sym2)} y x)
+(LEAL2 [off1] {sym1} x (LEAL1 [off2] {sym2} y y)) && is32Bit(off1+2*off2) && sym2 == nil ->
+      (LEAL4 [off1+2*off2] {sym1} x y)
+(LEAL4 [off1] {sym1} x (LEAL1 [off2] {sym2} y y)) && is32Bit(off1+4*off2) && sym2 == nil ->
+      (LEAL8 [off1+4*off2] {sym1} x y)
+
 // Absorb InvertFlags into branches.
 (LT (InvertFlags cmp) yes no) -> (GT cmp yes no)
 (GT (InvertFlags cmp) yes no) -> (LT cmp yes no)
@@ -1039,23 +934,27 @@
 // TEST %reg,%reg is shorter than CMP
 (CMP(L|W|B)const x [0]) -> (TEST(L|W|B) x x)
 
+// Convert LEAL1 back to ADDL if we can
+(LEAL1 [0] x y) && v.Aux == nil -> (ADDL x y)
+
 // Combining byte loads into larger (unaligned) loads.
 // There are many ways these combinations could occur.  This is
 // designed to match the way encoding/binary.LittleEndian does it.
-(ORL                  x0:(MOVBload [i0] {s} p mem)
-    s0:(SHLLconst [8] x1:(MOVBload [i1] {s} p mem)))
+(ORL                  x0:(MOVBload [i0] {s} p0 mem)
+    s0:(SHLLconst [8] x1:(MOVBload [i1] {s} p1 mem)))
   && i1 == i0+1
   && x0.Uses == 1
   && x1.Uses == 1
   && s0.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, s0)
-  -> @mergePoint(b,x0,x1) (MOVWload [i0] {s} p mem)
+  -> @mergePoint(b,x0,x1) (MOVWload [i0] {s} p0 mem)
 
 (ORL o0:(ORL
-                       x0:(MOVWload [i0] {s} p mem)
-    s0:(SHLLconst [16] x1:(MOVBload [i2] {s} p mem)))
-    s1:(SHLLconst [24] x2:(MOVBload [i3] {s} p mem)))
+                       x0:(MOVWload [i0] {s} p0 mem)
+    s0:(SHLLconst [16] x1:(MOVBload [i2] {s} p1 mem)))
+    s1:(SHLLconst [24] x2:(MOVBload [i3] {s} p2 mem)))
   && i2 == i0+2
   && i3 == i0+3
   && x0.Uses == 1
@@ -1064,126 +963,84 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && o0.Uses == 1
+  && same(p0, p1, 1)
+  && same(p1, p2, 1)
   && mergePoint(b,x0,x1,x2) != nil
   && clobber(x0, x1, x2, s0, s1, o0)
-  -> @mergePoint(b,x0,x1,x2) (MOVLload [i0] {s} p mem)
-
-(ORL                  x0:(MOVBloadidx1 [i0] {s} p idx mem)
-    s0:(SHLLconst [8] x1:(MOVBloadidx1 [i1] {s} p idx mem)))
-  && i1==i0+1
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && s0.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, s0)
-  -> @mergePoint(b,x0,x1) (MOVWloadidx1 <v.Type> [i0] {s} p idx mem)
-
-(ORL o0:(ORL
-                       x0:(MOVWloadidx1 [i0] {s} p idx mem)
-    s0:(SHLLconst [16] x1:(MOVBloadidx1 [i2] {s} p idx mem)))
-    s1:(SHLLconst [24] x2:(MOVBloadidx1 [i3] {s} p idx mem)))
-  && i2 == i0+2
-  && i3 == i0+3
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && x2.Uses == 1
-  && s0.Uses == 1
-  && s1.Uses == 1
-  && o0.Uses == 1
-  && mergePoint(b,x0,x1,x2) != nil
-  && clobber(x0, x1, x2, s0, s1, o0)
-  -> @mergePoint(b,x0,x1,x2) (MOVLloadidx1 <v.Type> [i0] {s} p idx mem)
+  -> @mergePoint(b,x0,x1,x2) (MOVLload [i0] {s} p0 mem)
 
 // Combine constant stores into larger (unaligned) stores.
-(MOVBstoreconst [c] {s} p x:(MOVBstoreconst [a] {s} p mem))
+(MOVBstoreconst [c] {s} p1 x:(MOVBstoreconst [a] {s} p0 mem))
   && x.Uses == 1
   && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p mem)
-(MOVBstoreconst [a] {s} p x:(MOVBstoreconst [c] {s} p mem))
+  -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p0 mem)
+(MOVBstoreconst [a] {s} p1 x:(MOVBstoreconst [c] {s} p0 mem))
   && x.Uses == 1
   && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p mem)
-(MOVWstoreconst [c] {s} p x:(MOVWstoreconst [a] {s} p mem))
+  -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p0 mem)
+(MOVWstoreconst [c] {s} p1 x:(MOVWstoreconst [a] {s} p0 mem))
   && x.Uses == 1
   && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p mem)
-(MOVWstoreconst [a] {s} p x:(MOVWstoreconst [c] {s} p mem))
+  -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p0 mem)
+(MOVWstoreconst [a] {s} p1 x:(MOVWstoreconst [c] {s} p0 mem))
   && x.Uses == 1
   && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p mem)
-
-(MOVBstoreconstidx1 [c] {s} p i x:(MOVBstoreconstidx1 [a] {s} p i mem))
-  && x.Uses == 1
-  && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
-  && clobber(x)
-  -> (MOVWstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p i mem)
-(MOVWstoreconstidx1 [c] {s} p i x:(MOVWstoreconstidx1 [a] {s} p i mem))
-  && x.Uses == 1
-  && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
-  && clobber(x)
-  -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p i mem)
-
-(MOVWstoreconstidx2 [c] {s} p i x:(MOVWstoreconstidx2 [a] {s} p i mem))
-  && x.Uses == 1
-  && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
-  && clobber(x)
-  -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p (SHLLconst <i.Type> [1] i) mem)
+  -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p0 mem)
 
 // Combine stores into larger (unaligned) stores.
-(MOVBstore [i] {s} p (SHR(W|L)const [8] w) x:(MOVBstore [i-1] {s} p w mem))
+(MOVBstore [i] {s} p1 (SHR(W|L)const [8] w) x:(MOVBstore [i-1] {s} p0 w mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVWstore [i-1] {s} p w mem)
-(MOVBstore [i] {s} p w x:(MOVBstore {s} [i+1] p (SHR(W|L)const [8] w) mem))
+  -> (MOVWstore [i-1] {s} p0 w mem)
+(MOVBstore [i] {s} p1 w x:(MOVBstore {s} [i+1] p0 (SHR(W|L)const [8] w) mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVWstore [i] {s} p w mem)
-(MOVBstore [i] {s} p (SHRLconst [j] w) x:(MOVBstore [i-1] {s} p w0:(SHRLconst [j-8] w) mem))
+  -> (MOVWstore [i] {s} p0 w mem)
+(MOVBstore [i] {s} p1 (SHRLconst [j] w) x:(MOVBstore [i-1] {s} p0 w0:(SHRLconst [j-8] w) mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVWstore [i-1] {s} p w0 mem)
-(MOVWstore [i] {s} p (SHRLconst [16] w) x:(MOVWstore [i-2] {s} p w mem))
+  -> (MOVWstore [i-1] {s} p0 w0 mem)
+(MOVWstore [i] {s} p1 (SHRLconst [16] w) x:(MOVWstore [i-2] {s} p0 w mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVLstore [i-2] {s} p w mem)
-(MOVWstore [i] {s} p (SHRLconst [j] w) x:(MOVWstore [i-2] {s} p w0:(SHRLconst [j-16] w) mem))
+  -> (MOVLstore [i-2] {s} p0 w mem)
+(MOVWstore [i] {s} p1 (SHRLconst [j] w) x:(MOVWstore [i-2] {s} p0 w0:(SHRLconst [j-16] w) mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVLstore [i-2] {s} p w0 mem)
+  -> (MOVLstore [i-2] {s} p0 w0 mem)
 
-(MOVBstoreidx1 [i] {s} p idx (SHR(L|W)const [8] w) x:(MOVBstoreidx1 [i-1] {s} p idx w mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVWstoreidx1 [i-1] {s} p idx w mem)
-(MOVBstoreidx1 [i] {s} p idx w x:(MOVBstoreidx1 [i+1] {s} p idx (SHR(L|W)const [8] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVWstoreidx1 [i] {s} p idx w mem)
-(MOVBstoreidx1 [i] {s} p idx (SHRLconst [j] w) x:(MOVBstoreidx1 [i-1] {s} p idx w0:(SHRLconst [j-8] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVWstoreidx1 [i-1] {s} p idx w0 mem)
-(MOVWstoreidx1 [i] {s} p idx (SHRLconst [16] w) x:(MOVWstoreidx1 [i-2] {s} p idx w mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVLstoreidx1 [i-2] {s} p idx w mem)
-(MOVWstoreidx1 [i] {s} p idx (SHRLconst [j] w) x:(MOVWstoreidx1 [i-2] {s} p idx w0:(SHRLconst [j-16] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVLstoreidx1 [i-2] {s} p idx w0 mem)
+// Move constant offsets from LEALx up into load. This lets the above combining
+// rules discover indexed load-combining instances.
+(MOV(B|W|L)load [i0] {s0} l:(LEAL1 [i1] {s1} x y) mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L)load [i0+i1] {s0} (LEAL1 <l.Type> [0] {s1} x y) mem)
+(MOV(B|W|L)load [i0] {s0} l:(LEAL2 [i1] {s1} x y) mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L)load [i0+i1] {s0} (LEAL2 <l.Type> [0] {s1} x y) mem)
+(MOV(B|W|L)load [i0] {s0} l:(LEAL4 [i1] {s1} x y) mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L)load [i0+i1] {s0} (LEAL4 <l.Type> [0] {s1} x y) mem)
+(MOV(B|W|L)load [i0] {s0} l:(LEAL8 [i1] {s1} x y) mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L)load [i0+i1] {s0} (LEAL8 <l.Type> [0] {s1} x y) mem)
 
-(MOVWstoreidx2 [i] {s} p idx (SHRLconst [16] w) x:(MOVWstoreidx2 [i-2] {s} p idx w mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVLstoreidx1 [i-2] {s} p (SHLLconst <idx.Type> [1] idx) w mem)
-(MOVWstoreidx2 [i] {s} p idx (SHRLconst [j] w) x:(MOVWstoreidx2 [i-2] {s} p idx w0:(SHRLconst [j-16] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVLstoreidx1 [i-2] {s} p (SHLLconst <idx.Type> [1] idx) w0 mem)
+(MOV(B|W|L)store [i0] {s0} l:(LEAL1 [i1] {s1} x y) val mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L)store [i0+i1] {s0} (LEAL1 <l.Type> [0] {s1} x y) val mem)
+(MOV(B|W|L)store [i0] {s0} l:(LEAL2 [i1] {s1} x y) val mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L)store [i0+i1] {s0} (LEAL2 <l.Type> [0] {s1} x y) val mem)
+(MOV(B|W|L)store [i0] {s0} l:(LEAL4 [i1] {s1} x y) val mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L)store [i0+i1] {s0} (LEAL4 <l.Type> [0] {s1} x y) val mem)
+(MOV(B|W|L)store [i0] {s0} l:(LEAL8 [i1] {s1} x y) val mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L)store [i0+i1] {s0} (LEAL8 <l.Type> [0] {s1} x y) val mem)
 
 // For PIC, break floating-point constant loading into two instructions so we have
 // a register to use for holding the address of the constant pool entry.

src/cmd/compile/internal/ssa/gen/AMD64.rules

@@ -1043,12 +1043,6 @@
 (MOVWQZX x) && zeroUpper48Bits(x,3) -> x
 (MOVBQZX x) && zeroUpper56Bits(x,3) -> x
 
-(MOVBQZX x:(MOVBloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVBloadidx1 <v.Type> [off] {sym} ptr idx mem)
-(MOVWQZX x:(MOVWloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWloadidx1 <v.Type> [off] {sym} ptr idx mem)
-(MOVWQZX x:(MOVWloadidx2 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVWloadidx2 <v.Type> [off] {sym} ptr idx mem)
-(MOVLQZX x:(MOVLloadidx1 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVLloadidx1 <v.Type> [off] {sym} ptr idx mem)
-(MOVLQZX x:(MOVLloadidx4 [off] {sym} ptr idx mem)) && x.Uses == 1 && clobber(x) -> @x.Block (MOVLloadidx4 <v.Type> [off] {sym} ptr idx mem)
-
 // replace load from same location as preceding store with zero/sign extension (or copy in case of full width)
 (MOVBload [off] {sym} ptr (MOVBstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> (MOVBQZX x)
 (MOVWload [off] {sym} ptr (MOVWstore [off2] {sym2} ptr2 x _)) && sym == sym2 && off == off2 && isSamePtr(ptr, ptr2) -> (MOVWQZX x)
@@ -1166,86 +1160,6 @@
 	&& is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
 	((ADD|SUB|AND|OR|XOR|BTC|BTR|BTS)Lmodify [off1+off2] {mergeSym(sym1,sym2)} base val mem)
 
-// generating indexed loads and stores
-(MOV(B|W|L|Q|SS|SD)load [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(B|W|L|Q|SS|SD)loadidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOVWload [off1] {sym1} (LEAQ2 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOVWloadidx2 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOV(L|SS)load [off1] {sym1} (LEAQ4 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(L|SS)loadidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOV(L|Q|SD)load [off1] {sym1} (LEAQ8 [off2] {sym2} ptr idx) mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(L|Q|SD)loadidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx mem)
-
-(MOV(B|W|L|Q|SS|SD)store [off1] {sym1} (LEAQ1 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(B|W|L|Q|SS|SD)storeidx1 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
-(MOVWstore [off1] {sym1} (LEAQ2 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOVWstoreidx2 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
-(MOV(L|SS)store [off1] {sym1} (LEAQ4 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(L|SS)storeidx4 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
-(MOV(L|Q|SD)store [off1] {sym1} (LEAQ8 [off2] {sym2} ptr idx) val mem) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
-	(MOV(L|Q|SD)storeidx8 [off1+off2] {mergeSym(sym1,sym2)} ptr idx val mem)
-
-(MOV(B|W|L|Q|SS|SD)load [off] {sym} (ADDQ ptr idx) mem) && ptr.Op != OpSB ->
-	(MOV(B|W|L|Q|SS|SD)loadidx1 [off] {sym} ptr idx mem)
-(MOV(B|W|L|Q|SS|SD)store [off] {sym} (ADDQ ptr idx) val mem) && ptr.Op != OpSB ->
-	(MOV(B|W|L|Q|SS|SD)storeidx1 [off] {sym} ptr idx val mem)
-
-(MOV(B|W|L|Q)storeconst [x] {sym1} (LEAQ1 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
-	(MOV(B|W|L|Q)storeconstidx1 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOVWstoreconst [x] {sym1} (LEAQ2 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
-	(MOVWstoreconstidx2 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOVLstoreconst [x] {sym1} (LEAQ4 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
-	(MOVLstoreconstidx4 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
-(MOVQstoreconst [x] {sym1} (LEAQ8 [off] {sym2} ptr idx) mem) && canMergeSym(sym1, sym2) ->
-	(MOVQstoreconstidx8 [ValAndOff(x).add(off)] {mergeSym(sym1,sym2)} ptr idx mem)
-
-(MOV(B|W|L|Q)storeconst [x] {sym} (ADDQ ptr idx) mem) -> (MOV(B|W|L|Q)storeconstidx1 [x] {sym} ptr idx mem)
-
-// combine SHLQ into indexed loads and stores
-(MOVWloadidx1 [c] {sym} ptr (SHLQconst [1] idx) mem) -> (MOVWloadidx2 [c] {sym} ptr idx mem)
-(MOV(L|SS)loadidx1 [c] {sym} ptr (SHLQconst [2] idx) mem) -> (MOV(L|SS)loadidx4 [c] {sym} ptr idx mem)
-(MOV(L|Q|SD)loadidx1 [c] {sym} ptr (SHLQconst [3] idx) mem) -> (MOV(L|Q|SD)loadidx8 [c] {sym} ptr idx mem)
-
-(MOVWstoreidx1 [c] {sym} ptr (SHLQconst [1] idx) val mem) -> (MOVWstoreidx2 [c] {sym} ptr idx val mem)
-(MOV(L|SS)storeidx1 [c] {sym} ptr (SHLQconst [2] idx) val mem) -> (MOV(L|SS)storeidx4 [c] {sym} ptr idx val mem)
-(MOV(L|Q|SD)storeidx1 [c] {sym} ptr (SHLQconst [3] idx) val mem) -> (MOV(L|Q|SD)storeidx8 [c] {sym} ptr idx val mem)
-(MOVWstoreconstidx1 [c] {sym} ptr (SHLQconst [1] idx) mem) -> (MOVWstoreconstidx2 [c] {sym} ptr idx mem)
-(MOVLstoreconstidx1 [c] {sym} ptr (SHLQconst [2] idx) mem) -> (MOVLstoreconstidx4 [c] {sym} ptr idx mem)
-(MOVQstoreconstidx1 [c] {sym} ptr (SHLQconst [3] idx) mem) -> (MOVQstoreconstidx8 [c] {sym} ptr idx mem)
-
-// combine ADDQ into pointer of indexed loads and stores
-(MOV(B|W|L|Q|SS|SD)loadidx1 [c] {sym} (ADDQconst [d] ptr) idx mem) && is32Bit(c+d) -> (MOV(B|W|L|Q|SS|SD)loadidx1 [c+d] {sym} ptr idx mem)
-(MOVWloadidx2 [c] {sym} (ADDQconst [d] ptr) idx mem) && is32Bit(c+d) -> (MOVWloadidx2 [c+d] {sym} ptr idx mem)
-(MOV(L|SS)loadidx4 [c] {sym} (ADDQconst [d] ptr) idx mem) && is32Bit(c+d) -> (MOV(L|SS)loadidx4 [c+d] {sym} ptr idx mem)
-(MOV(L|Q|SD)loadidx8 [c] {sym} (ADDQconst [d] ptr) idx mem) && is32Bit(c+d) -> (MOV(L|Q|SD)loadidx8 [c+d] {sym} ptr idx mem)
-
-(MOV(B|W|L|Q|SS|SD)storeidx1 [c] {sym} (ADDQconst [d] ptr) idx val mem) && is32Bit(c+d) -> (MOV(B|W|L|Q|SS|SD)storeidx1 [c+d] {sym} ptr idx val mem)
-(MOVWstoreidx2 [c] {sym} (ADDQconst [d] ptr) idx val mem) && is32Bit(c+d) -> (MOVWstoreidx2 [c+d] {sym} ptr idx val mem)
-(MOV(L|SS)storeidx4 [c] {sym} (ADDQconst [d] ptr) idx val mem) && is32Bit(c+d) -> (MOV(L|SS)storeidx4 [c+d] {sym} ptr idx val mem)
-(MOV(L|Q|SD)storeidx8 [c] {sym} (ADDQconst [d] ptr) idx val mem) && is32Bit(c+d) -> (MOV(L|Q|SD)storeidx8 [c+d] {sym} ptr idx val mem)
-
-
-// combine ADDQ into index of indexed loads and stores
-(MOV(B|W|L|Q|SS|SD)loadidx1 [c] {sym} ptr (ADDQconst [d] idx) mem)  && is32Bit(c+d) -> (MOV(B|W|L|Q|SS|SD)loadidx1 [c+d] {sym} ptr idx mem)
-(MOVWloadidx2 [c] {sym} ptr (ADDQconst [d] idx) mem)  && is32Bit(c+2*d) -> (MOVWloadidx2 [c+2*d] {sym} ptr idx mem)
-(MOV(L|SS)loadidx4 [c] {sym} ptr (ADDQconst [d] idx) mem)  && is32Bit(c+4*d) -> (MOV(L|SS)loadidx4 [c+4*d] {sym} ptr idx mem)
-(MOV(L|Q|SD)loadidx8 [c] {sym} ptr (ADDQconst [d] idx) mem)  && is32Bit(c+8*d) -> (MOV(L|Q|SD)loadidx8 [c+8*d] {sym} ptr idx mem)
-
-(MOV(B|W|L|Q|SS|SD)storeidx1 [c] {sym} ptr (ADDQconst [d] idx) val mem)  && is32Bit(c+d) -> (MOV(B|W|L|Q|SS|SD)storeidx1 [c+d] {sym} ptr idx val mem)
-(MOVWstoreidx2 [c] {sym} ptr (ADDQconst [d] idx) val mem)  && is32Bit(c+2*d) -> (MOVWstoreidx2 [c+2*d] {sym} ptr idx val mem)
-(MOV(L|SS)storeidx4 [c] {sym} ptr (ADDQconst [d] idx) val mem)  && is32Bit(c+4*d) -> (MOV(L|SS)storeidx4 [c+4*d] {sym} ptr idx val mem)
-(MOV(L|Q|SD)storeidx8 [c] {sym} ptr (ADDQconst [d] idx) val mem)  && is32Bit(c+8*d) -> (MOV(L|Q|SD)storeidx8 [c+8*d] {sym} ptr idx val mem)
-
-(MOV(B|W|L|Q)storeconstidx1 [x] {sym} (ADDQconst [c] ptr) idx mem) && ValAndOff(x).canAdd(c) -> (MOV(B|W|L|Q)storeconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-(MOVWstoreconstidx2 [x] {sym} (ADDQconst [c] ptr) idx mem) && ValAndOff(x).canAdd(c) -> (MOVWstoreconstidx2 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-(MOVLstoreconstidx4 [x] {sym} (ADDQconst [c] ptr) idx mem) && ValAndOff(x).canAdd(c) -> (MOVLstoreconstidx4 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-(MOVQstoreconstidx8 [x] {sym} (ADDQconst [c] ptr) idx mem) && ValAndOff(x).canAdd(c) -> (MOVQstoreconstidx8 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-
-(MOV(B|W|L|Q)storeconstidx1 [x] {sym} ptr (ADDQconst [c] idx) mem) && ValAndOff(x).canAdd(c) -> (MOV(B|W|L|Q)storeconstidx1 [ValAndOff(x).add(c)] {sym} ptr idx mem)
-(MOVWstoreconstidx2 [x] {sym} ptr (ADDQconst [c] idx) mem) && ValAndOff(x).canAdd(2*c) -> (MOVWstoreconstidx2 [ValAndOff(x).add(2*c)] {sym} ptr idx mem)
-(MOVLstoreconstidx4 [x] {sym} ptr (ADDQconst [c] idx) mem) && ValAndOff(x).canAdd(4*c) -> (MOVLstoreconstidx4 [ValAndOff(x).add(4*c)] {sym} ptr idx mem)
-(MOVQstoreconstidx8 [x] {sym} ptr (ADDQconst [c] idx) mem) && ValAndOff(x).canAdd(8*c) -> (MOVQstoreconstidx8 [ValAndOff(x).add(8*c)] {sym} ptr idx mem)
-
 // fold LEAQs together
 (LEAQ [off1] {sym1} (LEAQ [off2] {sym2} x)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
       (LEAQ [off1+off2] {mergeSym(sym1,sym2)} x)
@@ -1274,6 +1188,17 @@
 (LEAQ [off1] {sym1} (LEAQ8 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
       (LEAQ8 [off1+off2] {mergeSym(sym1,sym2)} x y)
 
+// LEAQ[1248] into LEAQ[1248]. Only some such merges are possible.
+(LEAQ1 [off1] {sym1} x (LEAQ1 [off2] {sym2} y y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
+      (LEAQ2 [off1+off2] {mergeSym(sym1, sym2)} x y)
+(LEAQ1 [off1] {sym1} x (LEAQ1 [off2] {sym2} x y)) && is32Bit(off1+off2) && canMergeSym(sym1, sym2) ->
+      (LEAQ2 [off1+off2] {mergeSym(sym1, sym2)} y x)
+(LEAQ2 [off1] {sym1} x (LEAQ1 [off2] {sym2} y y)) && is32Bit(off1+2*off2) && sym2 == nil ->
+      (LEAQ4 [off1+2*off2] {sym1} x y)
+(LEAQ4 [off1] {sym1} x (LEAQ1 [off2] {sym2} y y)) && is32Bit(off1+4*off2) && sym2 == nil ->
+      (LEAQ8 [off1+4*off2] {sym1} x y)
+// TODO: more?
+
 // Absorb InvertFlags into branches.
 (LT (InvertFlags cmp) yes no) -> (GT cmp yes no)
 (GT (InvertFlags cmp) yes no) -> (LT cmp yes no)
@@ -1329,7 +1254,10 @@
 (CMPWconst (ANDLconst _ [m]) [n]) && 0 <= int16(m) && int16(m) < int16(n) -> (FlagLT_ULT)
 (CMPBconst (ANDLconst _ [m]) [n]) && 0 <= int8(m) && int8(m) < int8(n) -> (FlagLT_ULT)
 
-(TEST(Q|L)const [c] (MOV(Q|L)const [c])) -> (FlagEQ)
+// TESTQ c c sets flags like CMPQ c 0.
+(TEST(Q|L)const [c] (MOV(Q|L)const [c])) && c == 0 -> (FlagEQ)
+(TEST(Q|L)const [c] (MOV(Q|L)const [c])) && c < 0 -> (FlagLT_UGT)
+(TEST(Q|L)const [c] (MOV(Q|L)const [c])) && c > 0 -> (FlagGT_UGT)
 
 // TODO: DIVxU also.
 
@@ -1552,60 +1480,65 @@
 
 // Little-endian loads
 
-(ORL                  x0:(MOVBload [i0] {s} p mem)
-    sh:(SHLLconst [8] x1:(MOVBload [i1] {s} p mem)))
+(ORL                  x0:(MOVBload [i0] {s} p0 mem)
+    sh:(SHLLconst [8] x1:(MOVBload [i1] {s} p1 mem)))
   && i1 == i0+1
   && x0.Uses == 1
   && x1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVWload [i0] {s} p mem)
+  -> @mergePoint(b,x0,x1) (MOVWload [i0] {s} p0 mem)
 
-(ORQ                  x0:(MOVBload [i0] {s} p mem)
-    sh:(SHLQconst [8] x1:(MOVBload [i1] {s} p mem)))
+(ORQ                  x0:(MOVBload [i0] {s} p0 mem)
+    sh:(SHLQconst [8] x1:(MOVBload [i1] {s} p1 mem)))
   && i1 == i0+1
   && x0.Uses == 1
   && x1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVWload [i0] {s} p mem)
+  -> @mergePoint(b,x0,x1) (MOVWload [i0] {s} p0 mem)
 
-(ORL                   x0:(MOVWload [i0] {s} p mem)
-    sh:(SHLLconst [16] x1:(MOVWload [i1] {s} p mem)))
+(ORL                   x0:(MOVWload [i0] {s} p0 mem)
+    sh:(SHLLconst [16] x1:(MOVWload [i1] {s} p1 mem)))
   && i1 == i0+2
   && x0.Uses == 1
   && x1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVLload [i0] {s} p mem)
+  -> @mergePoint(b,x0,x1) (MOVLload [i0] {s} p0 mem)
 
-(ORQ                   x0:(MOVWload [i0] {s} p mem)
-    sh:(SHLQconst [16] x1:(MOVWload [i1] {s} p mem)))
+(ORQ                   x0:(MOVWload [i0] {s} p0 mem)
+    sh:(SHLQconst [16] x1:(MOVWload [i1] {s} p1 mem)))
   && i1 == i0+2
   && x0.Uses == 1
   && x1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVLload [i0] {s} p mem)
+  -> @mergePoint(b,x0,x1) (MOVLload [i0] {s} p0 mem)
 
-(ORQ                   x0:(MOVLload [i0] {s} p mem)
-    sh:(SHLQconst [32] x1:(MOVLload [i1] {s} p mem)))
+(ORQ                   x0:(MOVLload [i0] {s} p0 mem)
+    sh:(SHLQconst [32] x1:(MOVLload [i1] {s} p1 mem)))
   && i1 == i0+4
   && x0.Uses == 1
   && x1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVQload [i0] {s} p mem)
+  -> @mergePoint(b,x0,x1) (MOVQload [i0] {s} p0 mem)
 
 (ORL
-    s1:(SHLLconst [j1] x1:(MOVBload [i1] {s} p mem))
+    s1:(SHLLconst [j1] x1:(MOVBload [i1] {s} p0 mem))
     or:(ORL
-        s0:(SHLLconst [j0] x0:(MOVBload [i0] {s} p mem))
+        s0:(SHLLconst [j0] x0:(MOVBload [i0] {s} p1 mem))
 	y))
   && i1 == i0+1
   && j1 == j0+8
@@ -1615,14 +1548,15 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1,y) != nil
   && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j0] (MOVWload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j0] (MOVWload [i0] {s} p0 mem)) y)
 
 (ORQ
-    s1:(SHLQconst [j1] x1:(MOVBload [i1] {s} p mem))
+    s1:(SHLQconst [j1] x1:(MOVBload [i1] {s} p0 mem))
     or:(ORQ
-        s0:(SHLQconst [j0] x0:(MOVBload [i0] {s} p mem))
+        s0:(SHLQconst [j0] x0:(MOVBload [i0] {s} p1 mem))
 	y))
   && i1 == i0+1
   && j1 == j0+8
@@ -1632,14 +1566,15 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1,y) != nil
   && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVWload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVWload [i0] {s} p0 mem)) y)
 
 (ORQ
-    s1:(SHLQconst [j1] x1:(MOVWload [i1] {s} p mem))
+    s1:(SHLQconst [j1] x1:(MOVWload [i1] {s} p0 mem))
     or:(ORQ
-        s0:(SHLQconst [j0] x0:(MOVWload [i0] {s} p mem))
+        s0:(SHLQconst [j0] x0:(MOVWload [i0] {s} p1 mem))
 	y))
   && i1 == i0+2
   && j1 == j0+16
@@ -1649,180 +1584,105 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1,y) != nil
   && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVLload [i0] {s} p mem)) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVLload [i0] {s} p0 mem)) y)
 
 // Little-endian indexed loads
 
-(ORL                  x0:(MOVBloadidx1 [i0] {s} p idx mem)
-    sh:(SHLLconst [8] x1:(MOVBloadidx1 [i1] {s} p idx mem)))
-  && i1 == i0+1
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVWloadidx1 <v.Type> [i0] {s} p idx mem)
+// Move constants offsets from LEAQx up into load. This lets the above combining
+// rules discover indexed load-combining instances.
+(MOV(B|W|L|Q)load [i0] {s0} l:(LEAQ1 [i1] {s1} x y) mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L|Q)load [i0+i1] {s0} (LEAQ1 <l.Type> [0] {s1} x y) mem)
+(MOV(B|W|L|Q)load [i0] {s0} l:(LEAQ2 [i1] {s1} x y) mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L|Q)load [i0+i1] {s0} (LEAQ2 <l.Type> [0] {s1} x y) mem)
+(MOV(B|W|L|Q)load [i0] {s0} l:(LEAQ4 [i1] {s1} x y) mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L|Q)load [i0+i1] {s0} (LEAQ4 <l.Type> [0] {s1} x y) mem)
+(MOV(B|W|L|Q)load [i0] {s0} l:(LEAQ8 [i1] {s1} x y) mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L|Q)load [i0+i1] {s0} (LEAQ8 <l.Type> [0] {s1} x y) mem)
 
-(ORQ                  x0:(MOVBloadidx1 [i0] {s} p idx mem)
-    sh:(SHLQconst [8] x1:(MOVBloadidx1 [i1] {s} p idx mem)))
-  && i1 == i0+1
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVWloadidx1 <v.Type> [i0] {s} p idx mem)
-
-(ORL                   x0:(MOVWloadidx1 [i0] {s} p idx mem)
-    sh:(SHLLconst [16] x1:(MOVWloadidx1 [i1] {s} p idx mem)))
-  && i1 == i0+2
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVLloadidx1 [i0] {s} p idx mem)
-
-(ORQ                   x0:(MOVWloadidx1 [i0] {s} p idx mem)
-    sh:(SHLQconst [16] x1:(MOVWloadidx1 [i1] {s} p idx mem)))
-  && i1 == i0+2
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVLloadidx1 [i0] {s} p idx mem)
-
-(ORQ                   x0:(MOVLloadidx1 [i0] {s} p idx mem)
-    sh:(SHLQconst [32] x1:(MOVLloadidx1 [i1] {s} p idx mem)))
-  && i1 == i0+4
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (MOVQloadidx1 [i0] {s} p idx mem)
-
-(ORL
-    s1:(SHLLconst [j1] x1:(MOVBloadidx1 [i1] {s} p idx mem))
-    or:(ORL
-        s0:(SHLLconst [j0] x0:(MOVBloadidx1 [i0] {s} p idx mem))
-	y))
-  && i1 == i0+1
-  && j1 == j0+8
-  && j0 % 16 == 0
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && s0.Uses == 1
-  && s1.Uses == 1
-  && or.Uses == 1
-  && mergePoint(b,x0,x1,y) != nil
-  && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j0] (MOVWloadidx1 [i0] {s} p idx mem)) y)
-
-(ORQ
-    s1:(SHLQconst [j1] x1:(MOVBloadidx1 [i1] {s} p idx mem))
-    or:(ORQ
-        s0:(SHLQconst [j0] x0:(MOVBloadidx1 [i0] {s} p idx mem))
-	y))
-  && i1 == i0+1
-  && j1 == j0+8
-  && j0 % 16 == 0
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && s0.Uses == 1
-  && s1.Uses == 1
-  && or.Uses == 1
-  && mergePoint(b,x0,x1,y) != nil
-  && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVWloadidx1 [i0] {s} p idx mem)) y)
-
-(ORQ
-    s1:(SHLQconst [j1] x1:(MOVWloadidx1 [i1] {s} p idx mem))
-    or:(ORQ
-        s0:(SHLQconst [j0] x0:(MOVWloadidx1 [i0] {s} p idx mem))
-	y))
-  && i1 == i0+2
-  && j1 == j0+16
-  && j0 % 32 == 0
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && s0.Uses == 1
-  && s1.Uses == 1
-  && or.Uses == 1
-  && mergePoint(b,x0,x1,y) != nil
-  && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j0] (MOVLloadidx1 [i0] {s} p idx mem)) y)
+(MOV(B|W|L|Q)store [i0] {s0} l:(LEAQ1 [i1] {s1} x y) val mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L|Q)store [i0+i1] {s0} (LEAQ1 <l.Type> [0] {s1} x y) val mem)
+(MOV(B|W|L|Q)store [i0] {s0} l:(LEAQ2 [i1] {s1} x y) val mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L|Q)store [i0+i1] {s0} (LEAQ2 <l.Type> [0] {s1} x y) val mem)
+(MOV(B|W|L|Q)store [i0] {s0} l:(LEAQ4 [i1] {s1} x y) val mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L|Q)store [i0+i1] {s0} (LEAQ4 <l.Type> [0] {s1} x y) val mem)
+(MOV(B|W|L|Q)store [i0] {s0} l:(LEAQ8 [i1] {s1} x y) val mem) && i1 != 0 && is32Bit(i0+i1)
+-> (MOV(B|W|L|Q)store [i0+i1] {s0} (LEAQ8 <l.Type> [0] {s1} x y) val mem)
 
 // Big-endian loads
 
 (ORL
-                       x1:(MOVBload [i1] {s} p mem)
-    sh:(SHLLconst [8]  x0:(MOVBload [i0] {s} p mem)))
+                       x1:(MOVBload [i1] {s} p0 mem)
+    sh:(SHLLconst [8]  x0:(MOVBload [i0] {s} p1 mem)))
   && i1 == i0+1
   && x0.Uses == 1
   && x1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (ROLWconst <v.Type> [8] (MOVWload [i0] {s} p mem))
+  -> @mergePoint(b,x0,x1) (ROLWconst <v.Type> [8] (MOVWload [i0] {s} p0 mem))
 
 (ORQ
-                       x1:(MOVBload [i1] {s} p mem)
-    sh:(SHLQconst [8]  x0:(MOVBload [i0] {s} p mem)))
+                       x1:(MOVBload [i1] {s} p0 mem)
+    sh:(SHLQconst [8]  x0:(MOVBload [i0] {s} p1 mem)))
   && i1 == i0+1
   && x0.Uses == 1
   && x1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (ROLWconst <v.Type> [8] (MOVWload [i0] {s} p mem))
+  -> @mergePoint(b,x0,x1) (ROLWconst <v.Type> [8] (MOVWload [i0] {s} p0 mem))
 
 (ORL
-                        r1:(ROLWconst [8] x1:(MOVWload [i1] {s} p mem))
-    sh:(SHLLconst [16]  r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p mem))))
+                        r1:(ROLWconst [8] x1:(MOVWload [i1] {s} p0 mem))
+    sh:(SHLLconst [16]  r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p1 mem))))
   && i1 == i0+2
   && x0.Uses == 1
   && x1.Uses == 1
   && r0.Uses == 1
   && r1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, r0, r1, sh)
-  -> @mergePoint(b,x0,x1) (BSWAPL <v.Type> (MOVLload [i0] {s} p mem))
+  -> @mergePoint(b,x0,x1) (BSWAPL <v.Type> (MOVLload [i0] {s} p0 mem))
 
 (ORQ
-                        r1:(ROLWconst [8] x1:(MOVWload [i1] {s} p mem))
-    sh:(SHLQconst [16]  r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p mem))))
+                        r1:(ROLWconst [8] x1:(MOVWload [i1] {s} p0 mem))
+    sh:(SHLQconst [16]  r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p1 mem))))
   && i1 == i0+2
   && x0.Uses == 1
   && x1.Uses == 1
   && r0.Uses == 1
   && r1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, r0, r1, sh)
-  -> @mergePoint(b,x0,x1) (BSWAPL <v.Type> (MOVLload [i0] {s} p mem))
+  -> @mergePoint(b,x0,x1) (BSWAPL <v.Type> (MOVLload [i0] {s} p0 mem))
 
 (ORQ
-                        r1:(BSWAPL x1:(MOVLload [i1] {s} p mem))
-    sh:(SHLQconst [32]  r0:(BSWAPL x0:(MOVLload [i0] {s} p mem))))
+                        r1:(BSWAPL x1:(MOVLload [i1] {s} p0 mem))
+    sh:(SHLQconst [32]  r0:(BSWAPL x0:(MOVLload [i0] {s} p1 mem))))
   && i1 == i0+4
   && x0.Uses == 1
   && x1.Uses == 1
   && r0.Uses == 1
   && r1.Uses == 1
   && sh.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1) != nil
   && clobber(x0, x1, r0, r1, sh)
-  -> @mergePoint(b,x0,x1) (BSWAPQ <v.Type> (MOVQload [i0] {s} p mem))
+  -> @mergePoint(b,x0,x1) (BSWAPQ <v.Type> (MOVQload [i0] {s} p0 mem))
 
 (ORL
-    s0:(SHLLconst [j0] x0:(MOVBload [i0] {s} p mem))
+    s0:(SHLLconst [j0] x0:(MOVBload [i0] {s} p0 mem))
     or:(ORL
-        s1:(SHLLconst [j1] x1:(MOVBload [i1] {s} p mem))
+        s1:(SHLLconst [j1] x1:(MOVBload [i1] {s} p1 mem))
 	y))
   && i1 == i0+1
   && j1 == j0-8
@@ -1832,14 +1692,15 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1,y) != nil
   && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWload [i0] {s} p mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWload [i0] {s} p0 mem))) y)
 
 (ORQ
-    s0:(SHLQconst [j0] x0:(MOVBload [i0] {s} p mem))
+    s0:(SHLQconst [j0] x0:(MOVBload [i0] {s} p0 mem))
     or:(ORQ
-        s1:(SHLQconst [j1] x1:(MOVBload [i1] {s} p mem))
+        s1:(SHLQconst [j1] x1:(MOVBload [i1] {s} p1 mem))
 	y))
   && i1 == i0+1
   && j1 == j0-8
@@ -1849,14 +1710,15 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1,y) != nil
   && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWload [i0] {s} p mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWload [i0] {s} p0 mem))) y)
 
 (ORQ
-    s0:(SHLQconst [j0] r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p mem)))
+    s0:(SHLQconst [j0] r0:(ROLWconst [8] x0:(MOVWload [i0] {s} p0 mem)))
     or:(ORQ
-        s1:(SHLQconst [j1] r1:(ROLWconst [8] x1:(MOVWload [i1] {s} p mem)))
+        s1:(SHLQconst [j1] r1:(ROLWconst [8] x1:(MOVWload [i1] {s} p1 mem)))
 	y))
   && i1 == i0+2
   && j1 == j0-16
@@ -1868,168 +1730,41 @@
   && s0.Uses == 1
   && s1.Uses == 1
   && or.Uses == 1
+  && same(p0, p1, 1)
   && mergePoint(b,x0,x1,y) != nil
   && clobber(x0, x1, r0, r1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (BSWAPL <typ.UInt32> (MOVLload [i0] {s} p mem))) y)
-
-// Big-endian indexed loads
-
-(ORL
-                       x1:(MOVBloadidx1 [i1] {s} p idx mem)
-    sh:(SHLLconst [8]  x0:(MOVBloadidx1 [i0] {s} p idx mem)))
-  && i1 == i0+1
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (ROLWconst <v.Type> [8] (MOVWloadidx1 [i0] {s} p idx mem))
-
-(ORQ
-                       x1:(MOVBloadidx1 [i1] {s} p idx mem)
-    sh:(SHLQconst [8]  x0:(MOVBloadidx1 [i0] {s} p idx mem)))
-  && i1 == i0+1
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, sh)
-  -> @mergePoint(b,x0,x1) (ROLWconst <v.Type> [8] (MOVWloadidx1 [i0] {s} p idx mem))
-
-(ORL
-                        r1:(ROLWconst [8] x1:(MOVWloadidx1 [i1] {s} p idx mem))
-    sh:(SHLLconst [16]  r0:(ROLWconst [8] x0:(MOVWloadidx1 [i0] {s} p idx mem))))
-  && i1 == i0+2
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && r0.Uses == 1
-  && r1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, r0, r1, sh)
-  -> @mergePoint(b,x0,x1) (BSWAPL <v.Type> (MOVLloadidx1 [i0] {s} p idx mem))
-
-(ORQ
-                        r1:(ROLWconst [8] x1:(MOVWloadidx1 [i1] {s} p idx mem))
-    sh:(SHLQconst [16]  r0:(ROLWconst [8] x0:(MOVWloadidx1 [i0] {s} p idx mem))))
-  && i1 == i0+2
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && r0.Uses == 1
-  && r1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, r0, r1, sh)
-  -> @mergePoint(b,x0,x1) (BSWAPL <v.Type> (MOVLloadidx1 [i0] {s} p idx mem))
-
-(ORQ
-                        r1:(BSWAPL x1:(MOVLloadidx1 [i1] {s} p idx mem))
-    sh:(SHLQconst [32]  r0:(BSWAPL x0:(MOVLloadidx1 [i0] {s} p idx mem))))
-  && i1 == i0+4
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && r0.Uses == 1
-  && r1.Uses == 1
-  && sh.Uses == 1
-  && mergePoint(b,x0,x1) != nil
-  && clobber(x0, x1, r0, r1, sh)
-  -> @mergePoint(b,x0,x1) (BSWAPQ <v.Type> (MOVQloadidx1 [i0] {s} p idx mem))
-
-(ORL
-    s0:(SHLLconst [j0] x0:(MOVBloadidx1 [i0] {s} p idx mem))
-    or:(ORL
-        s1:(SHLLconst [j1] x1:(MOVBloadidx1 [i1] {s} p idx mem))
-	y))
-  && i1 == i0+1
-  && j1 == j0-8
-  && j1 % 16 == 0
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && s0.Uses == 1
-  && s1.Uses == 1
-  && or.Uses == 1
-  && mergePoint(b,x0,x1,y) != nil
-  && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORL <v.Type> (SHLLconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWloadidx1 [i0] {s} p idx mem))) y)
-
-(ORQ
-    s0:(SHLQconst [j0] x0:(MOVBloadidx1 [i0] {s} p idx mem))
-    or:(ORQ
-        s1:(SHLQconst [j1] x1:(MOVBloadidx1 [i1] {s} p idx mem))
-	y))
-  && i1 == i0+1
-  && j1 == j0-8
-  && j1 % 16 == 0
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && s0.Uses == 1
-  && s1.Uses == 1
-  && or.Uses == 1
-  && mergePoint(b,x0,x1,y) != nil
-  && clobber(x0, x1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (ROLWconst <typ.UInt16> [8] (MOVWloadidx1 [i0] {s} p idx mem))) y)
-
-(ORQ
-    s0:(SHLQconst [j0] r0:(ROLWconst [8] x0:(MOVWloadidx1 [i0] {s} p idx mem)))
-    or:(ORQ
-        s1:(SHLQconst [j1] r1:(ROLWconst [8] x1:(MOVWloadidx1 [i1] {s} p idx mem)))
-	y))
-  && i1 == i0+2
-  && j1 == j0-16
-  && j1 % 32 == 0
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && r0.Uses == 1
-  && r1.Uses == 1
-  && s0.Uses == 1
-  && s1.Uses == 1
-  && or.Uses == 1
-  && mergePoint(b,x0,x1,y) != nil
-  && clobber(x0, x1, r0, r1, s0, s1, or)
-  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (BSWAPL <typ.UInt32> (MOVLloadidx1 [i0] {s} p idx mem))) y)
+  -> @mergePoint(b,x0,x1,y) (ORQ <v.Type> (SHLQconst <v.Type> [j1] (BSWAPL <typ.UInt32> (MOVLload [i0] {s} p0 mem))) y)
 
 // Combine 2 byte stores + shift into rolw 8 + word store
-(MOVBstore [i] {s} p w
-  x0:(MOVBstore [i-1] {s} p (SHRWconst [8] w) mem))
+(MOVBstore [i] {s} p1 w
+  x0:(MOVBstore [i-1] {s} p0 (SHRWconst [8] w) mem))
   && x0.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x0)
-  -> (MOVWstore [i-1] {s} p (ROLWconst <w.Type> [8] w) mem)
-
-(MOVBstoreidx1 [i] {s} p idx w
-  x0:(MOVBstoreidx1 [i-1] {s} p idx (SHRWconst [8] w) mem))
-  && x0.Uses == 1
-  && clobber(x0)
-  -> (MOVWstoreidx1 [i-1] {s} p idx (ROLWconst <w.Type> [8] w) mem)
+  -> (MOVWstore [i-1] {s} p0 (ROLWconst <w.Type> [8] w) mem)
 
 // Combine stores + shifts into bswap and larger (unaligned) stores
-(MOVBstore [i] {s} p w
-  x2:(MOVBstore [i-1] {s} p (SHRLconst [8] w)
-  x1:(MOVBstore [i-2] {s} p (SHRLconst [16] w)
-  x0:(MOVBstore [i-3] {s} p (SHRLconst [24] w) mem))))
+(MOVBstore [i] {s} p3 w
+  x2:(MOVBstore [i-1] {s} p2 (SHRLconst [8] w)
+  x1:(MOVBstore [i-2] {s} p1 (SHRLconst [16] w)
+  x0:(MOVBstore [i-3] {s} p0 (SHRLconst [24] w) mem))))
   && x0.Uses == 1
   && x1.Uses == 1
   && x2.Uses == 1
+  && same(p0, p1, 1)
+  && same(p1, p2, 1)
+  && same(p2, p3, 1)
   && clobber(x0, x1, x2)
-  -> (MOVLstore [i-3] {s} p (BSWAPL <w.Type> w) mem)
+  -> (MOVLstore [i-3] {s} p0 (BSWAPL <w.Type> w) mem)
 
-(MOVBstoreidx1 [i] {s} p idx w
-  x2:(MOVBstoreidx1 [i-1] {s} p idx (SHRLconst [8] w)
-  x1:(MOVBstoreidx1 [i-2] {s} p idx (SHRLconst [16] w)
-  x0:(MOVBstoreidx1 [i-3] {s} p idx (SHRLconst [24] w) mem))))
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && x2.Uses == 1
-  && clobber(x0, x1, x2)
-  -> (MOVLstoreidx1 [i-3] {s} p idx (BSWAPL <w.Type> w) mem)
-
-(MOVBstore [i] {s} p w
-  x6:(MOVBstore [i-1] {s} p (SHRQconst [8] w)
-  x5:(MOVBstore [i-2] {s} p (SHRQconst [16] w)
-  x4:(MOVBstore [i-3] {s} p (SHRQconst [24] w)
-  x3:(MOVBstore [i-4] {s} p (SHRQconst [32] w)
-  x2:(MOVBstore [i-5] {s} p (SHRQconst [40] w)
-  x1:(MOVBstore [i-6] {s} p (SHRQconst [48] w)
-  x0:(MOVBstore [i-7] {s} p (SHRQconst [56] w) mem))))))))
+(MOVBstore [i] {s} p7 w
+  x6:(MOVBstore [i-1] {s} p6 (SHRQconst [8] w)
+  x5:(MOVBstore [i-2] {s} p5 (SHRQconst [16] w)
+  x4:(MOVBstore [i-3] {s} p4 (SHRQconst [24] w)
+  x3:(MOVBstore [i-4] {s} p3 (SHRQconst [32] w)
+  x2:(MOVBstore [i-5] {s} p2 (SHRQconst [40] w)
+  x1:(MOVBstore [i-6] {s} p1 (SHRQconst [48] w)
+  x0:(MOVBstore [i-7] {s} p0 (SHRQconst [56] w) mem))))))))
   && x0.Uses == 1
   && x1.Uses == 1
   && x2.Uses == 1
@@ -2037,165 +1772,99 @@
   && x4.Uses == 1
   && x5.Uses == 1
   && x6.Uses == 1
+  && same(p0, p1, 1)
+  && same(p1, p2, 1)
+  && same(p2, p3, 1)
+  && same(p3, p4, 1)
+  && same(p4, p5, 1)
+  && same(p5, p6, 1)
+  && same(p6, p7, 1)
   && clobber(x0, x1, x2, x3, x4, x5, x6)
-  -> (MOVQstore [i-7] {s} p (BSWAPQ <w.Type> w) mem)
-
-(MOVBstoreidx1 [i] {s} p idx w
-  x6:(MOVBstoreidx1 [i-1] {s} p idx (SHRQconst [8] w)
-  x5:(MOVBstoreidx1 [i-2] {s} p idx (SHRQconst [16] w)
-  x4:(MOVBstoreidx1 [i-3] {s} p idx (SHRQconst [24] w)
-  x3:(MOVBstoreidx1 [i-4] {s} p idx (SHRQconst [32] w)
-  x2:(MOVBstoreidx1 [i-5] {s} p idx (SHRQconst [40] w)
-  x1:(MOVBstoreidx1 [i-6] {s} p idx (SHRQconst [48] w)
-  x0:(MOVBstoreidx1 [i-7] {s} p idx (SHRQconst [56] w) mem))))))))
-  && x0.Uses == 1
-  && x1.Uses == 1
-  && x2.Uses == 1
-  && x3.Uses == 1
-  && x4.Uses == 1
-  && x5.Uses == 1
-  && x6.Uses == 1
-  && clobber(x0, x1, x2, x3, x4, x5, x6)
-  -> (MOVQstoreidx1 [i-7] {s} p idx (BSWAPQ <w.Type> w) mem)
+  -> (MOVQstore [i-7] {s} p0 (BSWAPQ <w.Type> w) mem)
 
 // Combine constant stores into larger (unaligned) stores.
-(MOVBstoreconst [c] {s} p x:(MOVBstoreconst [a] {s} p mem))
+(MOVBstoreconst [c] {s} p1 x:(MOVBstoreconst [a] {s} p0 mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
   && clobber(x)
-  -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p mem)
-(MOVBstoreconst [a] {s} p x:(MOVBstoreconst [c] {s} p mem))
+  -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p0 mem)
+(MOVBstoreconst [a] {s} p1 x:(MOVBstoreconst [c] {s} p0 mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
   && clobber(x)
-  -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p mem)
-(MOVWstoreconst [c] {s} p x:(MOVWstoreconst [a] {s} p mem))
+  -> (MOVWstoreconst [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p0 mem)
+(MOVWstoreconst [c] {s} p1 x:(MOVWstoreconst [a] {s} p0 mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
   && clobber(x)
-  -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p mem)
-(MOVWstoreconst [a] {s} p x:(MOVWstoreconst [c] {s} p mem))
+  -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p0 mem)
+(MOVWstoreconst [a] {s} p1 x:(MOVWstoreconst [c] {s} p0 mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
   && clobber(x)
-  -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p mem)
-(MOVLstoreconst [c] {s} p x:(MOVLstoreconst [a] {s} p mem))
+  -> (MOVLstoreconst [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p0 mem)
+(MOVLstoreconst [c] {s} p1 x:(MOVLstoreconst [a] {s} p0 mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && ValAndOff(a).Off() + 4 == ValAndOff(c).Off()
   && clobber(x)
-  -> (MOVQstore [ValAndOff(a).Off()] {s} p (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
-(MOVLstoreconst [a] {s} p x:(MOVLstoreconst [c] {s} p mem))
+  -> (MOVQstore [ValAndOff(a).Off()] {s} p0 (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
+(MOVLstoreconst [a] {s} p1 x:(MOVLstoreconst [c] {s} p0 mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && ValAndOff(a).Off() + 4 == ValAndOff(c).Off()
   && clobber(x)
-  -> (MOVQstore [ValAndOff(a).Off()] {s} p (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
-(MOVQstoreconst [c] {s} p x:(MOVQstoreconst [c2] {s} p mem))
+  -> (MOVQstore [ValAndOff(a).Off()] {s} p0 (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
+(MOVQstoreconst [c] {s} p1 x:(MOVQstoreconst [c2] {s} p0 mem))
   && config.useSSE
   && x.Uses == 1
+  && same(p0, p1, 1)
   && ValAndOff(c2).Off() + 8 == ValAndOff(c).Off()
   && ValAndOff(c).Val() == 0
   && ValAndOff(c2).Val() == 0
   && clobber(x)
-  -> (MOVOstore [ValAndOff(c2).Off()] {s} p (MOVOconst [0]) mem)
-
-(MOVBstoreconstidx1 [c] {s} p i x:(MOVBstoreconstidx1 [a] {s} p i mem))
-  && x.Uses == 1
-  && ValAndOff(a).Off() + 1 == ValAndOff(c).Off()
-  && clobber(x)
-  -> (MOVWstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xff | ValAndOff(c).Val()<<8, ValAndOff(a).Off())] {s} p i mem)
-(MOVWstoreconstidx1 [c] {s} p i x:(MOVWstoreconstidx1 [a] {s} p i mem))
-  && x.Uses == 1
-  && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
-  && clobber(x)
-  -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p i mem)
-(MOVLstoreconstidx1 [c] {s} p i x:(MOVLstoreconstidx1 [a] {s} p i mem))
-  && x.Uses == 1
-  && ValAndOff(a).Off() + 4 == ValAndOff(c).Off()
-  && clobber(x)
-  -> (MOVQstoreidx1 [ValAndOff(a).Off()] {s} p i (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
-
-(MOVWstoreconstidx2 [c] {s} p i x:(MOVWstoreconstidx2 [a] {s} p i mem))
-  && x.Uses == 1
-  && ValAndOff(a).Off() + 2 == ValAndOff(c).Off()
-  && clobber(x)
-  -> (MOVLstoreconstidx1 [makeValAndOff(ValAndOff(a).Val()&0xffff | ValAndOff(c).Val()<<16, ValAndOff(a).Off())] {s} p (SHLQconst <i.Type> [1] i) mem)
-(MOVLstoreconstidx4 [c] {s} p i x:(MOVLstoreconstidx4 [a] {s} p i mem))
-  && x.Uses == 1
-  && ValAndOff(a).Off() + 4 == ValAndOff(c).Off()
-  && clobber(x)
-  -> (MOVQstoreidx1 [ValAndOff(a).Off()] {s} p (SHLQconst <i.Type> [2] i) (MOVQconst [ValAndOff(a).Val()&0xffffffff | ValAndOff(c).Val()<<32]) mem)
+  -> (MOVOstore [ValAndOff(c2).Off()] {s} p0 (MOVOconst [0]) mem)
 
 // Combine stores into larger (unaligned) stores.
-(MOVBstore [i] {s} p (SHR(W|L|Q)const [8] w) x:(MOVBstore [i-1] {s} p w mem))
+(MOVBstore [i] {s} p1 (SHR(W|L|Q)const [8] w) x:(MOVBstore [i-1] {s} p0 w mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVWstore [i-1] {s} p w mem)
-(MOVBstore [i] {s} p w x:(MOVBstore [i+1] {s} p (SHR(W|L|Q)const [8] w) mem))
+  -> (MOVWstore [i-1] {s} p0 w mem)
+(MOVBstore [i] {s} p1 w x:(MOVBstore [i+1] {s} p0 (SHR(W|L|Q)const [8] w) mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVWstore [i] {s} p w mem)
-(MOVBstore [i] {s} p (SHR(L|Q)const [j] w) x:(MOVBstore [i-1] {s} p w0:(SHR(L|Q)const [j-8] w) mem))
+  -> (MOVWstore [i] {s} p0 w mem)
+(MOVBstore [i] {s} p1 (SHR(L|Q)const [j] w) x:(MOVBstore [i-1] {s} p0 w0:(SHR(L|Q)const [j-8] w) mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVWstore [i-1] {s} p w0 mem)
-(MOVWstore [i] {s} p (SHR(L|Q)const [16] w) x:(MOVWstore [i-2] {s} p w mem))
+  -> (MOVWstore [i-1] {s} p0 w0 mem)
+(MOVWstore [i] {s} p1 (SHR(L|Q)const [16] w) x:(MOVWstore [i-2] {s} p0 w mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVLstore [i-2] {s} p w mem)
-(MOVWstore [i] {s} p (SHR(L|Q)const [j] w) x:(MOVWstore [i-2] {s} p w0:(SHR(L|Q)const [j-16] w) mem))
+  -> (MOVLstore [i-2] {s} p0 w mem)
+(MOVWstore [i] {s} p1 (SHR(L|Q)const [j] w) x:(MOVWstore [i-2] {s} p0 w0:(SHR(L|Q)const [j-16] w) mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVLstore [i-2] {s} p w0 mem)
-(MOVLstore [i] {s} p (SHRQconst [32] w) x:(MOVLstore [i-4] {s} p w mem))
+  -> (MOVLstore [i-2] {s} p0 w0 mem)
+(MOVLstore [i] {s} p1 (SHRQconst [32] w) x:(MOVLstore [i-4] {s} p0 w mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVQstore [i-4] {s} p w mem)
-(MOVLstore [i] {s} p (SHRQconst [j] w) x:(MOVLstore [i-4] {s} p w0:(SHRQconst [j-32] w) mem))
+  -> (MOVQstore [i-4] {s} p0 w mem)
+(MOVLstore [i] {s} p1 (SHRQconst [j] w) x:(MOVLstore [i-4] {s} p0 w0:(SHRQconst [j-32] w) mem))
   && x.Uses == 1
+  && same(p0, p1, 1)
   && clobber(x)
-  -> (MOVQstore [i-4] {s} p w0 mem)
-
-(MOVBstoreidx1 [i] {s} p idx (SHR(W|L|Q)const [8] w) x:(MOVBstoreidx1 [i-1] {s} p idx w mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVWstoreidx1 [i-1] {s} p idx w mem)
-(MOVBstoreidx1 [i] {s} p idx (SHR(L|Q)const [j] w) x:(MOVBstoreidx1 [i-1] {s} p idx w0:(SHR(L|Q)const [j-8] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVWstoreidx1 [i-1] {s} p idx w0 mem)
-(MOVWstoreidx1 [i] {s} p idx (SHR(L|Q)const [16] w) x:(MOVWstoreidx1 [i-2] {s} p idx w mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVLstoreidx1 [i-2] {s} p idx w mem)
-(MOVWstoreidx1 [i] {s} p idx (SHR(L|Q)const [j] w) x:(MOVWstoreidx1 [i-2] {s} p idx w0:(SHR(L|Q)const [j-16] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVLstoreidx1 [i-2] {s} p idx w0 mem)
-(MOVLstoreidx1 [i] {s} p idx (SHRQconst [32] w) x:(MOVLstoreidx1 [i-4] {s} p idx w mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVQstoreidx1 [i-4] {s} p idx w mem)
-(MOVLstoreidx1 [i] {s} p idx (SHRQconst [j] w) x:(MOVLstoreidx1 [i-4] {s} p idx w0:(SHRQconst [j-32] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVQstoreidx1 [i-4] {s} p idx w0 mem)
-
-(MOVWstoreidx2 [i] {s} p idx (SHR(L|Q)const [16] w) x:(MOVWstoreidx2 [i-2] {s} p idx w mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVLstoreidx1 [i-2] {s} p (SHLQconst <idx.Type> [1] idx) w mem)
-(MOVWstoreidx2 [i] {s} p idx (SHRQconst [j] w) x:(MOVWstoreidx2 [i-2] {s} p idx w0:(SHRQconst [j-16] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVLstoreidx1 [i-2] {s} p (SHLQconst <idx.Type> [1] idx) w0 mem)
-(MOVLstoreidx4 [i] {s} p idx (SHRQconst [32] w) x:(MOVLstoreidx4 [i-4] {s} p idx w mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVQstoreidx1 [i-4] {s} p (SHLQconst <idx.Type> [2] idx) w mem)
-(MOVLstoreidx4 [i] {s} p idx (SHRQconst [j] w) x:(MOVLstoreidx4 [i-4] {s} p idx w0:(SHRQconst [j-32] w) mem))
-  && x.Uses == 1
-  && clobber(x)
-  -> (MOVQstoreidx1 [i-4] {s} p (SHLQconst <idx.Type> [2] idx) w0 mem)
+  -> (MOVQstore [i-4] {s} p0 w0 mem)
 
 (MOVBstore [i] {s} p
   x1:(MOVBload [j] {s2} p2 mem)
@@ -2320,41 +1989,6 @@
 (BSFQ (ORQconst <t> [1<<8] (MOVBQZX x))) -> (BSFQ (ORQconst <t> [1<<8] x))
 (BSFQ (ORQconst <t> [1<<16] (MOVWQZX x))) -> (BSFQ (ORQconst <t> [1<<16] x))
 
-// Simplify indexed loads/stores
-(MOVBstoreidx1 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+c) -> (MOVBstore [i+c] {s} p w mem)
-(MOVWstoreidx1 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+c) -> (MOVWstore [i+c] {s} p w mem)
-(MOVLstoreidx1 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+c) -> (MOVLstore [i+c] {s} p w mem)
-(MOVQstoreidx1 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+c) -> (MOVQstore [i+c] {s} p w mem)
-(MOVWstoreidx2 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+2*c) -> (MOVWstore [i+2*c] {s} p w mem)
-(MOVLstoreidx4 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+4*c) -> (MOVLstore [i+4*c] {s} p w mem)
-(MOVLstoreidx8 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+8*c) -> (MOVLstore [i+8*c] {s} p w mem)
-(MOVQstoreidx8 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+8*c) -> (MOVQstore [i+8*c] {s} p w mem)
-(MOVSSstoreidx1 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+c) -> (MOVSSstore [i+c] {s} p w mem)
-(MOVSSstoreidx4 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+4*c) -> (MOVSSstore [i+4*c] {s} p w mem)
-(MOVSDstoreidx1 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+c) -> (MOVSDstore [i+c] {s} p w mem)
-(MOVSDstoreidx8 [i] {s} p (MOVQconst [c]) w mem) && is32Bit(i+8*c) -> (MOVSDstore [i+8*c] {s} p w mem)
-(MOVBloadidx1 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+c) -> (MOVBload [i+c] {s} p mem)
-(MOVWloadidx1 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+c) -> (MOVWload [i+c] {s} p mem)
-(MOVLloadidx1 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+c) -> (MOVLload [i+c] {s} p mem)
-(MOVQloadidx1 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+c) -> (MOVQload [i+c] {s} p mem)
-(MOVWloadidx2 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+2*c) -> (MOVWload [i+2*c] {s} p mem)
-(MOVLloadidx4 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+4*c) -> (MOVLload [i+4*c] {s} p mem)
-(MOVLloadidx8 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+8*c) -> (MOVLload [i+8*c] {s} p mem)
-(MOVQloadidx8 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+8*c) -> (MOVQload [i+8*c] {s} p mem)
-(MOVSSloadidx1 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+c) -> (MOVSSload [i+c] {s} p mem)
-(MOVSSloadidx4 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+4*c) -> (MOVSSload [i+4*c] {s} p mem)
-(MOVSDloadidx1 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+c) -> (MOVSDload [i+c] {s} p mem)
-(MOVSDloadidx8 [i] {s} p (MOVQconst [c]) mem) && is32Bit(i+8*c) -> (MOVSDload [i+8*c] {s} p mem)
-
-// Combine consts into storeidx.
-// Note that when c == 0, it takes more bytes to encode
-// the immediate $0 than to zero a register and use it.
-// We do the rewrite anyway, to minimize register pressure.
-(MOVBstoreidx1     [off] {s} ptr idx (MOVLconst [c]) mem) && validValAndOff(int64(int8(c)), off)  -> (MOVBstoreconstidx1     [makeValAndOff(int64(int8(c)), off)]  {s} ptr idx mem)
-(MOVWstoreidx(1|2) [off] {s} ptr idx (MOVLconst [c]) mem) && validValAndOff(int64(int16(c)), off) -> (MOVWstoreconstidx(1|2) [makeValAndOff(int64(int16(c)), off)] {s} ptr idx mem)
-(MOVLstoreidx(1|4) [off] {s} ptr idx (MOVQconst [c]) mem) && validValAndOff(int64(int32(c)), off) -> (MOVLstoreconstidx(1|4) [makeValAndOff(int64(int32(c)), off)] {s} ptr idx mem)
-(MOVQstoreidx(1|8) [off] {s} ptr idx (MOVQconst [c]) mem) && validValAndOff(c, off)               -> (MOVQstoreconstidx(1|8) [makeValAndOff(c, off)]               {s} ptr idx mem)
-
 // Redundant sign/zero extensions
 // Note: see issue 21963. We have to make sure we use the right type on
 // the resulting extension (the outer type, not the inner type).

src/cmd/compile/internal/ssa/html.go

@@ -245,6 +245,7 @@ dd.ssa-prog {
 svg {
     cursor: default;
     outline: 1px solid #eee;
+    width: 100%;
 }
 
 body.darkmode {
@@ -975,7 +976,7 @@ func (d *dotWriter) writeFuncSVG(w io.Writer, phase string, f *Func) {
 		fmt.Println(err)
 		return
 	}
-	fmt.Fprint(pipe, `digraph "" { margin=0; size="4,40"; ranksep=.2; `)
+	fmt.Fprint(pipe, `digraph "" { margin=0; ranksep=.2; `)
 	id := strings.Replace(phase, " ", "-", -1)
 	fmt.Fprintf(pipe, `id="g_graph_%s";`, id)
 	fmt.Fprintf(pipe, `node [style=filled,fillcolor=white,fontsize=16,fontname="Menlo,Times,serif",margin="0.01,0.03"];`)

src/cmd/compile/internal/ssa/prove.go

@@ -1305,9 +1305,9 @@ func isNonNegative(v *Value) bool {
 	if !v.Type.IsInteger() {
 		panic("isNonNegative bad type")
 	}
-	if !v.Type.IsSigned() {
-		return true
-	}
+	// TODO: return true if !v.Type.IsSigned()
+	// SSA isn't type-safe enough to do that now (issue 37753).
+	// The checks below depend only on the pattern of bits.
 
 	switch v.Op {
 	case OpConst64:

src/cmd/compile/internal/ssa/rewrite.go

@@ -1247,3 +1247,43 @@ func read64(sym interface{}, off int64, byteorder binary.ByteOrder) uint64 {
 	copy(buf, src)
 	return byteorder.Uint64(buf)
 }
+
+// same reports whether x and y are the same value.
+// It checks to a maximum depth of d, so it may report
+// a false negative.
+func same(x, y *Value, depth int) bool {
+	if x == y {
+		return true
+	}
+	if depth <= 0 {
+		return false
+	}
+	if x.Op != y.Op || x.Aux != y.Aux || x.AuxInt != y.AuxInt {
+		return false
+	}
+	if len(x.Args) != len(y.Args) {
+		return false
+	}
+	if opcodeTable[x.Op].commutative {
+		// Check exchanged ordering first.
+		for i, a := range x.Args {
+			j := i
+			if j < 2 {
+				j ^= 1
+			}
+			b := y.Args[j]
+			if !same(a, b, depth-1) {
+				goto checkNormalOrder
+			}
+		}
+		return true
+	checkNormalOrder:
+	}
+	for i, a := range x.Args {
+		b := y.Args[i]
+		if !same(a, b, depth-1) {
+			return false
+		}
+	}
+	return true
+}

src/cmd/compile/internal/syntax/scanner.go

@@ -50,16 +50,23 @@ func (s *scanner) init(src io.Reader, errh func(line, col uint, msg string), mod
 
 // errorf reports an error at the most recently read character position.
 func (s *scanner) errorf(format string, args ...interface{}) {
-	s.bad = true
 	s.error(fmt.Sprintf(format, args...))
 }
 
 // errorAtf reports an error at a byte column offset relative to the current token start.
 func (s *scanner) errorAtf(offset int, format string, args ...interface{}) {
-	s.bad = true
 	s.errh(s.line, s.col+uint(offset), fmt.Sprintf(format, args...))
 }
 
+// setLit sets the scanner state for a recognized _Literal token.
+func (s *scanner) setLit(kind LitKind, ok bool) {
+	s.nlsemi = true
+	s.tok = _Literal
+	s.lit = string(s.segment())
+	s.bad = !ok
+	s.kind = kind
+}
+
 // next advances the scanner by reading the next token.
 //
 // If a read, source encoding, or lexical error occurs, next calls
@@ -461,8 +468,8 @@ func (s *scanner) digits(base int, invalid *int) (digsep int) {
 }
 
 func (s *scanner) number(seenPoint bool) {
-	s.bad = false
-
+	ok := true
+	kind := IntLit
 	base := 10        // number base
 	prefix := rune(0) // one of 0 (decimal), '0' (0-octal), 'x', 'o', or 'b'
 	digsep := 0       // bit 0: digit present, bit 1: '_' present
@@ -470,7 +477,6 @@ func (s *scanner) number(seenPoint bool) {
 
 	// integer part
 	if !seenPoint {
-		s.kind = IntLit
 		if s.ch == '0' {
 			s.nextch()
 			switch lower(s.ch) {
@@ -491,7 +497,8 @@ func (s *scanner) number(seenPoint bool) {
 		digsep |= s.digits(base, &invalid)
 		if s.ch == '.' {
 			if prefix == 'o' || prefix == 'b' {
-				s.errorf("invalid radix point in %s", litname(prefix))
+				s.errorf("invalid radix point in %s literal", baseName(base))
+				ok = false
 			}
 			s.nextch()
 			seenPoint = true
@@ -500,68 +507,77 @@ func (s *scanner) number(seenPoint bool) {
 
 	// fractional part
 	if seenPoint {
-		s.kind = FloatLit
+		kind = FloatLit
 		digsep |= s.digits(base, &invalid)
 	}
 
-	if digsep&1 == 0 && !s.bad {
-		s.errorf("%s has no digits", litname(prefix))
+	if digsep&1 == 0 && ok {
+		s.errorf("%s literal has no digits", baseName(base))
+		ok = false
 	}
 
 	// exponent
 	if e := lower(s.ch); e == 'e' || e == 'p' {
-		if !s.bad {
+		if ok {
 			switch {
 			case e == 'e' && prefix != 0 && prefix != '0':
 				s.errorf("%q exponent requires decimal mantissa", s.ch)
+				ok = false
 			case e == 'p' && prefix != 'x':
 				s.errorf("%q exponent requires hexadecimal mantissa", s.ch)
+				ok = false
 			}
 		}
 		s.nextch()
-		s.kind = FloatLit
+		kind = FloatLit
 		if s.ch == '+' || s.ch == '-' {
 			s.nextch()
 		}
 		digsep = s.digits(10, nil) | digsep&2 // don't lose sep bit
-		if digsep&1 == 0 && !s.bad {
+		if digsep&1 == 0 && ok {
 			s.errorf("exponent has no digits")
+			ok = false
 		}
-	} else if prefix == 'x' && s.kind == FloatLit && !s.bad {
+	} else if prefix == 'x' && kind == FloatLit && ok {
 		s.errorf("hexadecimal mantissa requires a 'p' exponent")
+		ok = false
 	}
 
 	// suffix 'i'
 	if s.ch == 'i' {
-		s.kind = ImagLit
+		kind = ImagLit
 		s.nextch()
 	}
 
-	s.nlsemi = true
-	s.lit = string(s.segment())
-	s.tok = _Literal
+	s.setLit(kind, ok) // do this now so we can use s.lit below
 
-	if s.kind == IntLit && invalid >= 0 && !s.bad {
-		s.errorAtf(invalid, "invalid digit %q in %s", s.lit[invalid], litname(prefix))
+	if kind == IntLit && invalid >= 0 && ok {
+		s.errorAtf(invalid, "invalid digit %q in %s literal", s.lit[invalid], baseName(base))
+		ok = false
 	}
 
-	if digsep&2 != 0 && !s.bad {
+	if digsep&2 != 0 && ok {
 		if i := invalidSep(s.lit); i >= 0 {
 			s.errorAtf(i, "'_' must separate successive digits")
+			ok = false
 		}
 	}
+
+	s.bad = !ok // correct s.bad
 }
 
-func litname(prefix rune) string {
-	switch prefix {
-	case 'x':
-		return "hexadecimal literal"
-	case 'o', '0':
-		return "octal literal"
-	case 'b':
-		return "binary literal"
+func baseName(base int) string {
+	switch base {
+	case 2:
+		return "binary"
+	case 8:
+		return "octal"
+	case 10:
+		return "decimal"
+	case 16:
+		return "hexadecimal"
 	}
-	return "decimal literal"
+	panic("invalid base")
 }
 
 // invalidSep returns the index of the first invalid separator in x, or -1.
@@ -605,17 +621,19 @@ func invalidSep(x string) int {
 }
 
 func (s *scanner) rune() {
-	s.bad = false
+	ok := true
 	s.nextch()
 
 	n := 0
 	for ; ; n++ {
 		if s.ch == '\'' {
-			if !s.bad {
+			if ok {
 				if n == 0 {
 					s.errorf("empty rune literal or unescaped '")
+					ok = false
 				} else if n != 1 {
 					s.errorAtf(0, "more than one character in rune literal")
+					ok = false
 				}
 			}
 			s.nextch()
@@ -623,32 +641,33 @@ func (s *scanner) rune() {
 		}
 		if s.ch == '\\' {
 			s.nextch()
-			s.escape('\'')
+			if !s.escape('\'') {
+				ok = false
+			}
 			continue
 		}
 		if s.ch == '\n' {
-			if !s.bad {
+			if ok {
 				s.errorf("newline in rune literal")
+				ok = false
 			}
 			break
 		}
 		if s.ch < 0 {
-			if !s.bad {
+			if ok {
 				s.errorAtf(0, "rune literal not terminated")
+				ok = false
 			}
 			break
 		}
 		s.nextch()
 	}
 
-	s.nlsemi = true
-	s.lit = string(s.segment())
-	s.kind = RuneLit
-	s.tok = _Literal
+	s.setLit(RuneLit, ok)
 }
 
 func (s *scanner) stdString() {
-	s.bad = false
+	ok := true
 	s.nextch()
 
 	for {
@@ -658,28 +677,29 @@ func (s *scanner) stdString() {
 		}
 		if s.ch == '\\' {
 			s.nextch()
-			s.escape('"')
+			if !s.escape('"') {
+				ok = false
+			}
 			continue
 		}
 		if s.ch == '\n' {
 			s.errorf("newline in string")
+			ok = false
 			break
 		}
 		if s.ch < 0 {
 			s.errorAtf(0, "string not terminated")
+			ok = false
 			break
 		}
 		s.nextch()
 	}
 
-	s.nlsemi = true
-	s.lit = string(s.segment())
-	s.kind = StringLit
-	s.tok = _Literal
+	s.setLit(StringLit, ok)
 }
 
 func (s *scanner) rawString() {
-	s.bad = false
+	ok := true
 	s.nextch()
 
 	for {
@@ -689,6 +709,7 @@ func (s *scanner) rawString() {
 		}
 		if s.ch < 0 {
 			s.errorAtf(0, "string not terminated")
+			ok = false
 			break
 		}
 		s.nextch()
@@ -697,10 +718,7 @@ func (s *scanner) rawString() {
 	// literal (even though they are not part of the literal
 	// value).
 
-	s.nlsemi = true
-	s.lit = string(s.segment())
-	s.kind = StringLit
-	s.tok = _Literal
+	s.setLit(StringLit, ok)
 }
 
 func (s *scanner) comment(text string) {
@@ -797,14 +815,14 @@ func (s *scanner) fullComment() {
 	}
 }
 
-func (s *scanner) escape(quote rune) {
+func (s *scanner) escape(quote rune) bool {
 	var n int
 	var base, max uint32
 
 	switch s.ch {
 	case quote, 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\':
 		s.nextch()
-		return
+		return true
 	case '0', '1', '2', '3', '4', '5', '6', '7':
 		n, base, max = 3, 8, 255
 	case 'x':
@@ -818,16 +836,16 @@ func (s *scanner) escape(quote rune) {
 		n, base, max = 8, 16, unicode.MaxRune
 	default:
 		if s.ch < 0 {
-			return // complain in caller about EOF
+			return true // complain in caller about EOF
 		}
 		s.errorf("unknown escape")
-		return
+		return false
 	}
 
 	var x uint32
 	for i := n; i > 0; i-- {
 		if s.ch < 0 {
-			return // complain in caller about EOF
+			return true // complain in caller about EOF
 		}
 		d := base
 		if isDecimal(s.ch) {
@@ -836,12 +854,8 @@ func (s *scanner) escape(quote rune) {
 			d = uint32(lower(s.ch)) - 'a' + 10
 		}
 		if d >= base {
-			kind := "hex"
-			if base == 8 {
-				kind = "octal"
-			}
-			s.errorf("invalid character %q in %s escape", s.ch, kind)
-			return
+			s.errorf("invalid character %q in %s escape", s.ch, baseName(int(base)))
+			return false
 		}
 		// d < base
 		x = x*base + d
@@ -850,10 +864,13 @@ func (s *scanner) escape(quote rune) {
 
 	if x > max && base == 8 {
 		s.errorf("octal escape value %d > 255", x)
-		return
+		return false
 	}
 
 	if x > max || 0xD800 <= x && x < 0xE000 /* surrogate range */ {
 		s.errorf("escape is invalid Unicode code point %#U", x)
+		return false
 	}
+
+	return true
 }

src/cmd/compile/internal/syntax/scanner_test.go

@@ -613,9 +613,9 @@ func TestScanErrors(t *testing.T) {
 		{`'\`, "rune literal not terminated", 0, 0},
 		{`'\'`, "rune literal not terminated", 0, 0},
 		{`'\x`, "rune literal not terminated", 0, 0},
-		{`'\x'`, "invalid character '\\'' in hex escape", 0, 3},
+		{`'\x'`, "invalid character '\\'' in hexadecimal escape", 0, 3},
 		{`'\y'`, "unknown escape", 0, 2},
-		{`'\x0'`, "invalid character '\\'' in hex escape", 0, 4},
+		{`'\x0'`, "invalid character '\\'' in hexadecimal escape", 0, 4},
 		{`'\00'`, "invalid character '\\'' in octal escape", 0, 4},
 		{`'\377' /*`, "comment not terminated", 0, 7}, // valid octal escape
 		{`'\378`, "invalid character '8' in octal escape", 0, 4},
@@ -633,9 +633,9 @@ func TestScanErrors(t *testing.T) {
 		{`"\`, "string not terminated", 0, 0},
 		{`"\"`, "string not terminated", 0, 0},
 		{`"\x`, "string not terminated", 0, 0},
-		{`"\x"`, "invalid character '\"' in hex escape", 0, 3},
+		{`"\x"`, "invalid character '\"' in hexadecimal escape", 0, 3},
 		{`"\y"`, "unknown escape", 0, 2},
-		{`"\x0"`, "invalid character '\"' in hex escape", 0, 4},
+		{`"\x0"`, "invalid character '\"' in hexadecimal escape", 0, 4},
 		{`"\00"`, "invalid character '\"' in octal escape", 0, 4},
 		{`"\377" /*`, "comment not terminated", 0, 7}, // valid octal escape
 		{`"\378"`, "invalid character '8' in octal escape", 0, 4},
@@ -644,8 +644,8 @@ func TestScanErrors(t *testing.T) {
 		{`s := "foo\z"`, "unknown escape", 0, 10},
 		{`s := "foo\z00\nbar"`, "unknown escape", 0, 10},
 		{`"\x`, "string not terminated", 0, 0},
-		{`"\x"`, "invalid character '\"' in hex escape", 0, 3},
-		{`var s string = "\x"`, "invalid character '\"' in hex escape", 0, 18},
+		{`"\x"`, "invalid character '\"' in hexadecimal escape", 0, 3},
+		{`var s string = "\x"`, "invalid character '\"' in hexadecimal escape", 0, 18},
 		{`return "\Uffffffff"`, "escape is invalid Unicode code point U+FFFFFFFF", 0, 18},
 
 		{"0b.0", "invalid radix point in binary literal", 0, 2},
@@ -687,6 +687,48 @@ func TestScanErrors(t *testing.T) {
 	}
 }
 
+func TestDirectives(t *testing.T) {
+	for _, src := range []string{
+		"line",
+		"// line",
+		"//line",
+		"//line foo",
+		"//line foo%bar",
+
+		"go",
+		"// go:",
+		"//go:",
+		"//go :foo",
+		"//go:foo",
+		"//go:foo%bar",
+	} {
+		got := ""
+		var s scanner
+		s.init(strings.NewReader(src), func(_, col uint, msg string) {
+			if col != colbase {
+				t.Errorf("%s: got col = %d; want %d", src, col, colbase)
+			}
+			if msg == "" {
+				t.Errorf("%s: handler called with empty msg", src)
+			}
+			got = msg
+		}, directives)
+
+		s.next()
+		if strings.HasPrefix(src, "//line ") || strings.HasPrefix(src, "//go:") {
+			// handler should have been called
+			if got != src {
+				t.Errorf("got %s; want %s", got, src)
+			}
+		} else {
+			// handler should not have been called
+			if got != "" {
+				t.Errorf("got %s for %s", got, src)
+			}
+		}
+	}
+}
+
 func TestIssue21938(t *testing.T) {
 	s := "/*" + strings.Repeat(" ", 4089) + "*/ .5"
 

src/cmd/cover/cover.go

@@ -293,6 +293,11 @@ func (f *File) Visit(node ast.Node) ast.Visitor {
 			ast.Walk(f, n.Assign)
 			return nil
 		}
+	case *ast.FuncDecl:
+		// Don't annotate functions with blank names - they cannot be executed.
+		if n.Name.Name == "_" {
+			return nil
+		}
 	}
 	return f
 }

src/cmd/dist/test.go

@@ -98,9 +98,11 @@ func (t *tester) run() {
 		os.Setenv("PATH", fmt.Sprintf("%s%c%s", gobin, os.PathListSeparator, os.Getenv("PATH")))
 	}
 
-	slurp, err := exec.Command("go", "env", "CGO_ENABLED").Output()
+	cmd := exec.Command("go", "env", "CGO_ENABLED")
+	cmd.Stderr = new(bytes.Buffer)
+	slurp, err := cmd.Output()
 	if err != nil {
-		fatalf("Error running go env CGO_ENABLED: %v", err)
+		fatalf("Error running go env CGO_ENABLED: %v\n%s", err, cmd.Stderr)
 	}
 	t.cgoEnabled, _ = strconv.ParseBool(strings.TrimSpace(string(slurp)))
 	if flag.NArg() > 0 && t.runRxStr != "" {

src/cmd/go.mod

@@ -3,11 +3,10 @@ module cmd
 go 1.14
 
 require (
-	github.com/google/pprof v0.0.0-20200212024743-f11f1df84d12
+	github.com/google/pprof v0.0.0-20200229191704-1ebb73c60ed3
 	golang.org/x/arch v0.0.0-20191126211547-368ea8f32fff
 	golang.org/x/crypto v0.0.0-20200214034016-1d94cc7ab1c6
 	golang.org/x/mod v0.2.0
 	golang.org/x/sys v0.0.0-20200219091948-cb0a6d8edb6c // indirect
-	golang.org/x/tools v0.0.0-20200219195521-7c4b6277d74d
-	golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 // indirect
+	golang.org/x/tools v0.0.0-20200309180859-aa4048aca1ca
 )

src/cmd/go.sum

@@ -1,8 +1,9 @@
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
+github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e h1:fY5BOSpyZCqRo5OhCuC+XN+r/bBCmeuuJtjz+bCNIf8=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
 github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
-github.com/google/pprof v0.0.0-20200212024743-f11f1df84d12 h1:TgXhFz35pKlZuUz1pNlOKk1UCSXPpuUIc144Wd7SxCA=
-github.com/google/pprof v0.0.0-20200212024743-f11f1df84d12/go.mod h1:ZgVRPoUq/hfqzAqh7sHMqb3I9Rq5C59dIz2SbBwJ4eM=
+github.com/google/pprof v0.0.0-20200229191704-1ebb73c60ed3 h1:SRgJV+IoxM5MKyFdlSUeNy6/ycRUF2yBAKdAQswoHUk=
+github.com/google/pprof v0.0.0-20200229191704-1ebb73c60ed3/go.mod h1:ZgVRPoUq/hfqzAqh7sHMqb3I9Rq5C59dIz2SbBwJ4eM=
 github.com/ianlancetaylor/demangle v0.0.0-20181102032728-5e5cf60278f6 h1:UDMh68UUwekSh5iP2OMhRRZJiiBccgV7axzUG8vi56c=
 github.com/ianlancetaylor/demangle v0.0.0-20181102032728-5e5cf60278f6/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
 golang.org/x/arch v0.0.0-20191126211547-368ea8f32fff h1:k/MrR0lKiCokRu1JUDDAWhWZinfBAOZRzz3LkPOkFMs=
@@ -12,12 +13,13 @@ golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 h1:ObdrDkeb4kJdCP557AjRjq
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200214034016-1d94cc7ab1c6 h1:Sy5bstxEqwwbYs6n0/pBuxKENqOeZUgD45Gp3Q3pqLg=
 golang.org/x/crypto v0.0.0-20200214034016-1d94cc7ab1c6/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
 golang.org/x/mod v0.2.0 h1:KU7oHjnv3XNWfa5COkzUifxZmxp1TyI7ImMXqFxLwvQ=
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20200226121028-0de0cce0169b/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191204072324-ce4227a45e2e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -27,8 +29,8 @@ golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e h1:aZzprAO9/8oim3qStq3wc1Xuxx4QmAGriC4VU4ojemQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.0.0-20200219195521-7c4b6277d74d h1:ZQ18He7VORO2x4IEBuwfdp56K+ftEzRjvL0cFuCGCcM=
-golang.org/x/tools v0.0.0-20200219195521-7c4b6277d74d/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
+golang.org/x/tools v0.0.0-20200309180859-aa4048aca1ca h1:cFQHQhDv9N1vc+64dtXDAyd3exHDGfRTtveOnD0IsLI=
+golang.org/x/tools v0.0.0-20200309180859-aa4048aca1ca/go.mod h1:o4KQGtdN14AW+yjsvvwRTJJuXz8XRtIHtEnmAXLyFUw=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898 h1:/atklqdjdhuosWIl6AIbOeHJjicWYPqR9bpxqxYG2pA=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

src/cmd/go/go_test.go

@@ -1044,6 +1044,7 @@ func TestGetGitDefaultBranch(t *testing.T) {
 func TestAccidentalGitCheckout(t *testing.T) {
 	testenv.MustHaveExternalNetwork(t)
 	testenv.MustHaveExecPath(t, "git")
+	testenv.MustHaveExecPath(t, "svn")
 
 	tg := testgo(t)
 	defer tg.cleanup()
@@ -2208,15 +2209,10 @@ func testBuildmodePIE(t *testing.T, useCgo bool) {
 			t.Fatal(err)
 		}
 		defer f.Close()
-		const (
-			IMAGE_FILE_RELOCS_STRIPPED               = 0x0001
-			IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA = 0x0020
-			IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE    = 0x0040
-		)
 		if f.Section(".reloc") == nil {
 			t.Error(".reloc section is not present")
 		}
-		if (f.FileHeader.Characteristics & IMAGE_FILE_RELOCS_STRIPPED) != 0 {
+		if (f.FileHeader.Characteristics & pe.IMAGE_FILE_RELOCS_STRIPPED) != 0 {
 			t.Error("IMAGE_FILE_RELOCS_STRIPPED flag is set")
 		}
 		var dc uint16
@@ -2225,13 +2221,13 @@ func testBuildmodePIE(t *testing.T, useCgo bool) {
 			dc = oh.DllCharacteristics
 		case *pe.OptionalHeader64:
 			dc = oh.DllCharacteristics
-			if (dc & IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA) == 0 {
+			if (dc & pe.IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA) == 0 {
 				t.Error("IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA flag is not set")
 			}
 		default:
 			t.Fatalf("unexpected optional header type of %T", f.OptionalHeader)
 		}
-		if (dc & IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE) == 0 {
+		if (dc & pe.IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE) == 0 {
 			t.Error("IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE flag is not set")
 		}
 	default:

src/cmd/go/internal/auth/auth.go

@@ -10,10 +10,12 @@ import "net/http"
 // AddCredentials fills in the user's credentials for req, if any.
 // The return value reports whether any matching credentials were found.
 func AddCredentials(req *http.Request) (added bool) {
+	host := req.URL.Hostname()
+
 	// TODO(golang.org/issue/26232): Support arbitrary user-provided credentials.
 	netrcOnce.Do(readNetrc)
 	for _, l := range netrc {
-		if l.machine == req.URL.Host {
+		if l.machine == host {
 			req.SetBasicAuth(l.login, l.password)
 			return true
 		}

src/cmd/go/internal/lockedfile/internal/filelock/filelock_fcntl.go

@@ -13,19 +13,19 @@
 // or an F_OFD_SETLK command for 'fcntl', that allows for better concurrency and
 // does not require per-inode bookkeeping in the application.
 //
-// TODO(bcmills): If we add a build tag for Illumos (see golang.org/issue/20603)
-// then Illumos should use F_OFD_SETLK, and the resulting code would be as
-// simple as filelock_unix.go. We will still need the code in this file for AIX
-// or as long as Oracle Solaris provides only F_SETLK.
+// TODO(golang.org/issue/35618): add a syscall.Flock binding for Illumos and
+// switch it over to use filelock_unix.go.
 
 package filelock
 
 import (
 	"errors"
 	"io"
+	"math/rand"
 	"os"
 	"sync"
 	"syscall"
+	"time"
 )
 
 type lockType int16
@@ -91,7 +91,67 @@ func lock(f File, lt lockType) (err error) {
 		wait <- f
 	}
 
-	err = setlkw(f.Fd(), lt)
+	// Spurious EDEADLK errors arise on platforms that compute deadlock graphs at
+	// the process, rather than thread, level. Consider processes P and Q, with
+	// threads P.1, P.2, and Q.3. The following trace is NOT a deadlock, but will be
+	// reported as a deadlock on systems that consider only process granularity:
+	//
+	// 	P.1 locks file A.
+	// 	Q.3 locks file B.
+	// 	Q.3 blocks on file A.
+	// 	P.2 blocks on file B. (This is erroneously reported as a deadlock.)
+	// 	P.1 unlocks file A.
+	// 	Q.3 unblocks and locks file A.
+	// 	Q.3 unlocks files A and B.
+	// 	P.2 unblocks and locks file B.
+	// 	P.2 unlocks file B.
+	//
+	// These spurious errors were observed in practice on AIX and Solaris in
+	// cmd/go: see https://golang.org/issue/32817.
+	//
+	// We work around this bug by treating EDEADLK as always spurious. If there
+	// really is a lock-ordering bug between the interacting processes, it will
+	// become a livelock instead, but that's not appreciably worse than if we had
+	// a proper flock implementation (which generally does not even attempt to
+	// diagnose deadlocks).
+	//
+	// In the above example, that changes the trace to:
+	//
+	// 	P.1 locks file A.
+	// 	Q.3 locks file B.
+	// 	Q.3 blocks on file A.
+	// 	P.2 spuriously fails to lock file B and goes to sleep.
+	// 	P.1 unlocks file A.
+	// 	Q.3 unblocks and locks file A.
+	// 	Q.3 unlocks files A and B.
+	// 	P.2 wakes up and locks file B.
+	// 	P.2 unlocks file B.
+	//
+	// We know that the retry loop will not introduce a *spurious* livelock
+	// because, according to the POSIX specification, EDEADLK is only to be
+	// returned when “the lock is blocked by a lock from another process”.
+	// If that process is blocked on some lock that we are holding, then the
+	// resulting livelock is due to a real deadlock (and would manifest as such
+	// when using, for example, the flock implementation of this package).
+	// If the other process is *not* blocked on some other lock that we are
+	// holding, then it will eventually release the requested lock.
+
+	nextSleep := 1 * time.Millisecond
+	const maxSleep = 500 * time.Millisecond
+	for {
+		err = setlkw(f.Fd(), lt)
+		if err != syscall.EDEADLK {
+			break
+		}
+		time.Sleep(nextSleep)
+
+		nextSleep += nextSleep
+		if nextSleep > maxSleep {
+			nextSleep = maxSleep
+		}
+		// Apply 10% jitter to avoid synchronizing collisions when we finally unblock.
+		nextSleep += time.Duration((0.1*rand.Float64() - 0.05) * float64(nextSleep))
+	}
 
 	if err != nil {
 		unlock(f)

src/cmd/go/internal/lockedfile/lockedfile_test.go

@@ -8,8 +8,11 @@
 package lockedfile_test
 
 import (
+	"fmt"
+	"internal/testenv"
 	"io/ioutil"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"testing"
 	"time"
@@ -172,3 +175,98 @@ func TestCanLockExistingFile(t *testing.T) {
 	f.Close()
 	wait(t)
 }
+
+// TestSpuriousEDEADLK verifies that the spurious EDEADLK reported in
+// https://golang.org/issue/32817 no longer occurs.
+func TestSpuriousEDEADLK(t *testing.T) {
+	// 	P.1 locks file A.
+	// 	Q.3 locks file B.
+	// 	Q.3 blocks on file A.
+	// 	P.2 blocks on file B. (Spurious EDEADLK occurs here.)
+	// 	P.1 unlocks file A.
+	// 	Q.3 unblocks and locks file A.
+	// 	Q.3 unlocks files A and B.
+	// 	P.2 unblocks and locks file B.
+	// 	P.2 unlocks file B.
+
+	testenv.MustHaveExec(t)
+
+	dirVar := t.Name() + "DIR"
+
+	if dir := os.Getenv(dirVar); dir != "" {
+		// Q.3 locks file B.
+		b, err := lockedfile.Edit(filepath.Join(dir, "B"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer b.Close()
+
+		if err := ioutil.WriteFile(filepath.Join(dir, "locked"), []byte("ok"), 0666); err != nil {
+			t.Fatal(err)
+		}
+
+		// Q.3 blocks on file A.
+		a, err := lockedfile.Edit(filepath.Join(dir, "A"))
+		// Q.3 unblocks and locks file A.
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer a.Close()
+
+		// Q.3 unlocks files A and B.
+		return
+	}
+
+	dir, remove := mustTempDir(t)
+	defer remove()
+
+	// P.1 locks file A.
+	a, err := lockedfile.Edit(filepath.Join(dir, "A"))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	cmd := exec.Command(os.Args[0], "-test.run="+t.Name())
+	cmd.Env = append(os.Environ(), fmt.Sprintf("%s=%s", dirVar, dir))
+
+	qDone := make(chan struct{})
+	waitQ := mustBlock(t, "Edit A and B in subprocess", func() {
+		out, err := cmd.CombinedOutput()
+		if err != nil {
+			t.Errorf("%v:\n%s", err, out)
+		}
+		close(qDone)
+	})
+
+	// Wait until process Q has either failed or locked file B.
+	// Otherwise, P.2 might not block on file B as intended.
+locked:
+	for {
+		if _, err := os.Stat(filepath.Join(dir, "locked")); !os.IsNotExist(err) {
+			break locked
+		}
+		select {
+		case <-qDone:
+			break locked
+		case <-time.After(1 * time.Millisecond):
+		}
+	}
+
+	waitP2 := mustBlock(t, "Edit B", func() {
+		// P.2 blocks on file B. (Spurious EDEADLK occurs here.)
+		b, err := lockedfile.Edit(filepath.Join(dir, "B"))
+		// P.2 unblocks and locks file B.
+		if err != nil {
+			t.Error(err)
+			return
+		}
+		// P.2 unlocks file B.
+		b.Close()
+	})
+
+	// P.1 unlocks file A.
+	a.Close()
+
+	waitQ(t)
+	waitP2(t)
+}

src/cmd/go/internal/modcmd/verify.go

@@ -6,6 +6,7 @@ package modcmd
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -67,12 +68,10 @@ func verifyMod(mod module.Version) bool {
 		_, zipErr = os.Stat(zip)
 	}
 	dir, dirErr := modfetch.DownloadDir(mod)
-	if dirErr == nil {
-		_, dirErr = os.Stat(dir)
-	}
 	data, err := ioutil.ReadFile(zip + "hash")
 	if err != nil {
-		if zipErr != nil && os.IsNotExist(zipErr) && dirErr != nil && os.IsNotExist(dirErr) {
+		if zipErr != nil && errors.Is(zipErr, os.ErrNotExist) &&
+			dirErr != nil && errors.Is(dirErr, os.ErrNotExist) {
 			// Nothing downloaded yet. Nothing to verify.
 			return true
 		}
@@ -81,7 +80,7 @@ func verifyMod(mod module.Version) bool {
 	}
 	h := string(bytes.TrimSpace(data))
 
-	if zipErr != nil && os.IsNotExist(zipErr) {
+	if zipErr != nil && errors.Is(zipErr, os.ErrNotExist) {
 		// ok
 	} else {
 		hZ, err := dirhash.HashZip(zip, dirhash.DefaultHash)
@@ -93,7 +92,7 @@ func verifyMod(mod module.Version) bool {
 			ok = false
 		}
 	}
-	if dirErr != nil && os.IsNotExist(dirErr) {
+	if dirErr != nil && errors.Is(dirErr, os.ErrNotExist) {
 		// ok
 	} else {
 		hD, err := dirhash.HashDir(dir, mod.Path+"@"+mod.Version, dirhash.DefaultHash)

src/cmd/go/internal/modfetch/cache.go

@@ -7,6 +7,7 @@ package modfetch
 import (
 	"bytes"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -56,8 +57,11 @@ func CachePath(m module.Version, suffix string) (string, error) {
 	return filepath.Join(dir, encVer+"."+suffix), nil
 }
 
-// DownloadDir returns the directory to which m should be downloaded.
-// Note that the directory may not yet exist.
+// DownloadDir returns the directory to which m should have been downloaded.
+// An error will be returned if the module path or version cannot be escaped.
+// An error satisfying errors.Is(err, os.ErrNotExist) will be returned
+// along with the directory if the directory does not exist or if the directory
+// is not completely populated.
 func DownloadDir(m module.Version) (string, error) {
 	if PkgMod == "" {
 		return "", fmt.Errorf("internal error: modfetch.PkgMod not set")
@@ -76,9 +80,39 @@ func DownloadDir(m module.Version) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	return filepath.Join(PkgMod, enc+"@"+encVer), nil
+
+	dir := filepath.Join(PkgMod, enc+"@"+encVer)
+	if fi, err := os.Stat(dir); os.IsNotExist(err) {
+		return dir, err
+	} else if err != nil {
+		return dir, &DownloadDirPartialError{dir, err}
+	} else if !fi.IsDir() {
+		return dir, &DownloadDirPartialError{dir, errors.New("not a directory")}
+	}
+	partialPath, err := CachePath(m, "partial")
+	if err != nil {
+		return dir, err
+	}
+	if _, err := os.Stat(partialPath); err == nil {
+		return dir, &DownloadDirPartialError{dir, errors.New("not completely extracted")}
+	} else if !os.IsNotExist(err) {
+		return dir, err
+	}
+	return dir, nil
 }
 
+// DownloadDirPartialError is returned by DownloadDir if a module directory
+// exists but was not completely populated.
+//
+// DownloadDirPartialError is equivalent to os.ErrNotExist.
+type DownloadDirPartialError struct {
+	Dir string
+	Err error
+}
+
+func (e *DownloadDirPartialError) Error() string     { return fmt.Sprintf("%s: %v", e.Dir, e.Err) }
+func (e *DownloadDirPartialError) Is(err error) bool { return err == os.ErrNotExist }
+
 // lockVersion locks a file within the module cache that guards the downloading
 // and extraction of the zipfile for the given module version.
 func lockVersion(mod module.Version) (unlock func(), err error) {

src/cmd/go/internal/modfetch/coderepo.go

@@ -563,7 +563,7 @@ func (r *codeRepo) validatePseudoVersion(info *codehost.RevInfo, version string)
 		return err
 	}
 	if !t.Equal(info.Time.Truncate(time.Second)) {
-		return fmt.Errorf("does not match version-control timestamp (%s)", info.Time.UTC().Format(time.RFC3339))
+		return fmt.Errorf("does not match version-control timestamp (expected %s)", info.Time.UTC().Format(pseudoVersionTimestampFormat))
 	}
 
 	tagPrefix := ""

src/cmd/go/internal/modfetch/fetch.go

@@ -46,24 +46,26 @@ func Download(mod module.Version) (dir string, err error) {
 		err error
 	}
 	c := downloadCache.Do(mod, func() interface{} {
-		dir, err := DownloadDir(mod)
+		dir, err := download(mod)
 		if err != nil {
 			return cached{"", err}
 		}
-		if err := download(mod, dir); err != nil {
-			return cached{"", err}
-		}
 		checkMod(mod)
 		return cached{dir, nil}
 	}).(cached)
 	return c.dir, c.err
 }
 
-func download(mod module.Version, dir string) (err error) {
-	// If the directory exists, the module has already been extracted.
-	fi, err := os.Stat(dir)
-	if err == nil && fi.IsDir() {
-		return nil
+func download(mod module.Version) (dir string, err error) {
+	// If the directory exists, and no .partial file exists, the module has
+	// already been completely extracted. .partial files may be created when a
+	// module zip directory is extracted in place instead of being extracted to a
+	// temporary directory and renamed.
+	dir, err = DownloadDir(mod)
+	if err == nil {
+		return dir, nil
+	} else if dir == "" || !errors.Is(err, os.ErrNotExist) {
+		return "", err
 	}
 
 	// To avoid cluttering the cache with extraneous files,
@@ -71,22 +73,24 @@ func download(mod module.Version, dir string) (err error) {
 	// Invoke DownloadZip before locking the file.
 	zipfile, err := DownloadZip(mod)
 	if err != nil {
-		return err
+		return "", err
 	}
 
 	unlock, err := lockVersion(mod)
 	if err != nil {
-		return err
+		return "", err
 	}
 	defer unlock()
 
 	// Check whether the directory was populated while we were waiting on the lock.
-	fi, err = os.Stat(dir)
-	if err == nil && fi.IsDir() {
-		return nil
+	_, dirErr := DownloadDir(mod)
+	if dirErr == nil {
+		return dir, nil
 	}
+	_, dirExists := dirErr.(*DownloadDirPartialError)
 
-	// Clean up any remaining temporary directories from previous runs.
+	// Clean up any remaining temporary directories from previous runs, as well
+	// as partially extracted diectories created by future versions of cmd/go.
 	// This is only safe to do because the lock file ensures that their writers
 	// are no longer active.
 	parentDir := filepath.Dir(dir)
@@ -96,35 +100,75 @@ func download(mod module.Version, dir string) (err error) {
 			RemoveAll(path) // best effort
 		}
 	}
-
-	// Extract the zip file to a temporary directory, then rename it to the
-	// final path. That way, we can use the existence of the source directory to
-	// signal that it has been extracted successfully, and if someone deletes
-	// the entire directory (e.g. as an attempt to prune out file corruption)
-	// the module cache will still be left in a recoverable state.
-	// We retry failed renames using robustio.Rename on Windows. Programs that
-	// open files in the temporary directory (antivirus, search indexers, etc.)
-	// can cause os.Rename to fail with ERROR_ACCESS_DENIED.
-	if err := os.MkdirAll(parentDir, 0777); err != nil {
-		return err
-	}
-	tmpDir, err := ioutil.TempDir(parentDir, tmpPrefix)
-	if err != nil {
-		return err
-	}
-	defer func() {
-		if err != nil {
-			RemoveAll(tmpDir)
+	if dirExists {
+		if err := RemoveAll(dir); err != nil {
+			return "", err
 		}
-	}()
-
-	if err := modzip.Unzip(tmpDir, mod, zipfile); err != nil {
-		fmt.Fprintf(os.Stderr, "-> %s\n", err)
-		return err
 	}
 
-	if err := robustio.Rename(tmpDir, dir); err != nil {
-		return err
+	partialPath, err := CachePath(mod, "partial")
+	if err != nil {
+		return "", err
+	}
+	if err := os.Remove(partialPath); err != nil && !os.IsNotExist(err) {
+		return "", err
+	}
+
+	// Extract the module zip directory.
+	//
+	// By default, we extract to a temporary directory, then atomically rename to
+	// its final location. We use the existence of the source directory to signal
+	// that it has been extracted successfully (see DownloadDir).  If someone
+	// deletes the entire directory (e.g., as an attempt to prune out file
+	// corruption), the module cache will still be left in a recoverable
+	// state.
+	//
+	// Unfortunately, os.Rename may fail with ERROR_ACCESS_DENIED on Windows if
+	// another process opens files in the temporary directory. This is partially
+	// mitigated by using robustio.Rename, which retries os.Rename for a short
+	// time.
+	//
+	// To avoid this error completely, if unzipInPlace is set, we instead create a
+	// .partial file (indicating the directory isn't fully extracted), then we
+	// extract the directory at its final location, then we delete the .partial
+	// file. This is not the default behavior because older versions of Go may
+	// simply stat the directory to check whether it exists without looking for a
+	// .partial file. If multiple versions run concurrently, the older version may
+	// assume a partially extracted directory is complete.
+	// TODO(golang.org/issue/36568): when these older versions are no longer
+	// supported, remove the old default behavior and the unzipInPlace flag.
+	if err := os.MkdirAll(parentDir, 0777); err != nil {
+		return "", err
+	}
+
+	if unzipInPlace {
+		if err := ioutil.WriteFile(partialPath, nil, 0666); err != nil {
+			return "", err
+		}
+		if err := modzip.Unzip(dir, mod, zipfile); err != nil {
+			fmt.Fprintf(os.Stderr, "-> %s\n", err)
+			if rmErr := RemoveAll(dir); rmErr == nil {
+				os.Remove(partialPath)
+			}
+			return "", err
+		}
+		if err := os.Remove(partialPath); err != nil {
+			return "", err
+		}
+	} else {
+		tmpDir, err := ioutil.TempDir(parentDir, tmpPrefix)
+		if err != nil {
+			return "", err
+		}
+		if err := modzip.Unzip(tmpDir, mod, zipfile); err != nil {
+			fmt.Fprintf(os.Stderr, "-> %s\n", err)
+			RemoveAll(tmpDir)
+			return "", err
+		}
+		if err := robustio.Rename(tmpDir, dir); err != nil {
+			RemoveAll(tmpDir)
+			return "", err
+		}
 	}
 
 	if !cfg.ModCacheRW {
@@ -132,7 +176,18 @@ func download(mod module.Version, dir string) (err error) {
 		// os.Rename was observed to fail for read-only directories on macOS.
 		makeDirsReadOnly(dir)
 	}
-	return nil
+	return dir, nil
+}
+
+var unzipInPlace bool
+
+func init() {
+	for _, f := range strings.Split(os.Getenv("GODEBUG"), ",") {
+		if f == "modcacheunzipinplace=1" {
+			unzipInPlace = true
+			break
+		}
+	}
 }
 
 var downloadZipCache par.Cache
@@ -306,7 +361,7 @@ func RemoveAll(dir string) error {
 		}
 		return nil
 	})
-	return os.RemoveAll(dir)
+	return robustio.RemoveAll(dir)
 }
 
 var GoSumFile string // path to go.sum; set by package modload

src/cmd/go/internal/modfetch/pseudo.go

@@ -48,6 +48,8 @@ import (
 
 var pseudoVersionRE = lazyregexp.New(`^v[0-9]+\.(0\.0-|\d+\.\d+-([^+]*\.)?0\.)\d{14}-[A-Za-z0-9]+(\+[0-9A-Za-z-]+(\.[0-9A-Za-z-]+)*)?$`)
 
+const pseudoVersionTimestampFormat = "20060102150405"
+
 // PseudoVersion returns a pseudo-version for the given major version ("v1")
 // preexisting older tagged version ("" or "v1.2.3" or "v1.2.3-pre"), revision time,
 // and revision identifier (usually a 12-byte commit hash prefix).
@@ -55,7 +57,7 @@ func PseudoVersion(major, older string, t time.Time, rev string) string {
 	if major == "" {
 		major = "v0"
 	}
-	segment := fmt.Sprintf("%s-%s", t.UTC().Format("20060102150405"), rev)
+	segment := fmt.Sprintf("%s-%s", t.UTC().Format(pseudoVersionTimestampFormat), rev)
 	build := semver.Build(older)
 	older = semver.Canonical(older)
 	if older == "" {

src/cmd/go/internal/modload/build.go

@@ -148,9 +148,7 @@ func moduleInfo(m module.Version, fromBuildList bool) *modinfo.ModulePublic {
 			}
 			dir, err := modfetch.DownloadDir(mod)
 			if err == nil {
-				if info, err := os.Stat(dir); err == nil && info.IsDir() {
-					m.Dir = dir
-				}
+				m.Dir = dir
 			}
 		}
 	}

src/cmd/go/internal/modload/init.go

@@ -59,27 +59,6 @@ var (
 	allowMissingModuleImports bool
 )
 
-var modFile *modfile.File
-
-// A modFileIndex is an index of data corresponding to a modFile
-// at a specific point in time.
-type modFileIndex struct {
-	data         []byte
-	dataNeedsFix bool // true if fixVersion applied a change while parsing data
-	module       module.Version
-	goVersion    string
-	require      map[module.Version]requireMeta
-	replace      map[module.Version]module.Version
-	exclude      map[module.Version]bool
-}
-
-// index is the index of the go.mod file as of when it was last read or written.
-var index *modFileIndex
-
-type requireMeta struct {
-	indirect bool
-}
-
 // ModFile returns the parsed go.mod file.
 //
 // Note that after calling ImportPaths or LoadBuildList,
@@ -555,101 +534,6 @@ func setDefaultBuildMod() {
 	}
 }
 
-// checkVendorConsistency verifies that the vendor/modules.txt file matches (if
-// go 1.14) or at least does not contradict (go 1.13 or earlier) the
-// requirements and replacements listed in the main module's go.mod file.
-func checkVendorConsistency() {
-	readVendorList()
-
-	pre114 := false
-	if modFile.Go == nil || semver.Compare("v"+modFile.Go.Version, "v1.14") < 0 {
-		// Go versions before 1.14 did not include enough information in
-		// vendor/modules.txt to check for consistency.
-		// If we know that we're on an earlier version, relax the consistency check.
-		pre114 = true
-	}
-
-	vendErrors := new(strings.Builder)
-	vendErrorf := func(mod module.Version, format string, args ...interface{}) {
-		detail := fmt.Sprintf(format, args...)
-		if mod.Version == "" {
-			fmt.Fprintf(vendErrors, "\n\t%s: %s", mod.Path, detail)
-		} else {
-			fmt.Fprintf(vendErrors, "\n\t%s@%s: %s", mod.Path, mod.Version, detail)
-		}
-	}
-
-	for _, r := range modFile.Require {
-		if !vendorMeta[r.Mod].Explicit {
-			if pre114 {
-				// Before 1.14, modules.txt did not indicate whether modules were listed
-				// explicitly in the main module's go.mod file.
-				// However, we can at least detect a version mismatch if packages were
-				// vendored from a non-matching version.
-				if vv, ok := vendorVersion[r.Mod.Path]; ok && vv != r.Mod.Version {
-					vendErrorf(r.Mod, fmt.Sprintf("is explicitly required in go.mod, but vendor/modules.txt indicates %s@%s", r.Mod.Path, vv))
-				}
-			} else {
-				vendErrorf(r.Mod, "is explicitly required in go.mod, but not marked as explicit in vendor/modules.txt")
-			}
-		}
-	}
-
-	describe := func(m module.Version) string {
-		if m.Version == "" {
-			return m.Path
-		}
-		return m.Path + "@" + m.Version
-	}
-
-	// We need to verify *all* replacements that occur in modfile: even if they
-	// don't directly apply to any module in the vendor list, the replacement
-	// go.mod file can affect the selected versions of other (transitive)
-	// dependencies
-	for _, r := range modFile.Replace {
-		vr := vendorMeta[r.Old].Replacement
-		if vr == (module.Version{}) {
-			if pre114 && (r.Old.Version == "" || vendorVersion[r.Old.Path] != r.Old.Version) {
-				// Before 1.14, modules.txt omitted wildcard replacements and
-				// replacements for modules that did not have any packages to vendor.
-			} else {
-				vendErrorf(r.Old, "is replaced in go.mod, but not marked as replaced in vendor/modules.txt")
-			}
-		} else if vr != r.New {
-			vendErrorf(r.Old, "is replaced by %s in go.mod, but marked as replaced by %s in vendor/modules.txt", describe(r.New), describe(vr))
-		}
-	}
-
-	for _, mod := range vendorList {
-		meta := vendorMeta[mod]
-		if meta.Explicit {
-			if _, inGoMod := index.require[mod]; !inGoMod {
-				vendErrorf(mod, "is marked as explicit in vendor/modules.txt, but not explicitly required in go.mod")
-			}
-		}
-	}
-
-	for _, mod := range vendorReplaced {
-		r := Replacement(mod)
-		if r == (module.Version{}) {
-			vendErrorf(mod, "is marked as replaced in vendor/modules.txt, but not replaced in go.mod")
-			continue
-		}
-		if meta := vendorMeta[mod]; r != meta.Replacement {
-			vendErrorf(mod, "is marked as replaced by %s in vendor/modules.txt, but replaced by %s in go.mod", describe(meta.Replacement), describe(r))
-		}
-	}
-
-	if vendErrors.Len() > 0 {
-		base.Fatalf("go: inconsistent vendoring in %s:%s\n\nrun 'go mod vendor' to sync, or use -mod=mod or -mod=readonly to ignore the vendor directory", modRoot, vendErrors)
-	}
-}
-
-// Allowed reports whether module m is allowed (not excluded) by the main module's go.mod.
-func Allowed(m module.Version) bool {
-	return index == nil || !index.exclude[m]
-}
-
 func legacyModInit() {
 	if modFile == nil {
 		path, err := findModulePath(modRoot)
@@ -983,113 +867,3 @@ func WriteGoMod() {
 		base.Fatalf("go: updating go.mod: %v", err)
 	}
 }
-
-// indexModFile rebuilds the index of modFile.
-// If modFile has been changed since it was first read,
-// modFile.Cleanup must be called before indexModFile.
-func indexModFile(data []byte, modFile *modfile.File, needsFix bool) *modFileIndex {
-	i := new(modFileIndex)
-	i.data = data
-	i.dataNeedsFix = needsFix
-
-	i.module = module.Version{}
-	if modFile.Module != nil {
-		i.module = modFile.Module.Mod
-	}
-
-	i.goVersion = ""
-	if modFile.Go != nil {
-		i.goVersion = modFile.Go.Version
-	}
-
-	i.require = make(map[module.Version]requireMeta, len(modFile.Require))
-	for _, r := range modFile.Require {
-		i.require[r.Mod] = requireMeta{indirect: r.Indirect}
-	}
-
-	i.replace = make(map[module.Version]module.Version, len(modFile.Replace))
-	for _, r := range modFile.Replace {
-		if prev, dup := i.replace[r.Old]; dup && prev != r.New {
-			base.Fatalf("go: conflicting replacements for %v:\n\t%v\n\t%v", r.Old, prev, r.New)
-		}
-		i.replace[r.Old] = r.New
-	}
-
-	i.exclude = make(map[module.Version]bool, len(modFile.Exclude))
-	for _, x := range modFile.Exclude {
-		i.exclude[x.Mod] = true
-	}
-
-	return i
-}
-
-// modFileIsDirty reports whether the go.mod file differs meaningfully
-// from what was indexed.
-// If modFile has been changed (even cosmetically) since it was first read,
-// modFile.Cleanup must be called before modFileIsDirty.
-func (i *modFileIndex) modFileIsDirty(modFile *modfile.File) bool {
-	if i == nil {
-		return modFile != nil
-	}
-
-	if i.dataNeedsFix {
-		return true
-	}
-
-	if modFile.Module == nil {
-		if i.module != (module.Version{}) {
-			return true
-		}
-	} else if modFile.Module.Mod != i.module {
-		return true
-	}
-
-	if modFile.Go == nil {
-		if i.goVersion != "" {
-			return true
-		}
-	} else if modFile.Go.Version != i.goVersion {
-		if i.goVersion == "" && cfg.BuildMod == "readonly" {
-			// go.mod files did not always require a 'go' version, so do not error out
-			// if one is missing — we may be inside an older module in the module
-			// cache, and should bias toward providing useful behavior.
-		} else {
-			return true
-		}
-	}
-
-	if len(modFile.Require) != len(i.require) ||
-		len(modFile.Replace) != len(i.replace) ||
-		len(modFile.Exclude) != len(i.exclude) {
-		return true
-	}
-
-	for _, r := range modFile.Require {
-		if meta, ok := i.require[r.Mod]; !ok {
-			return true
-		} else if r.Indirect != meta.indirect {
-			if cfg.BuildMod == "readonly" {
-				// The module's requirements are consistent; only the "// indirect"
-				// comments that are wrong. But those are only guaranteed to be accurate
-				// after a "go mod tidy" — it's a good idea to run those before
-				// committing a change, but it's certainly not mandatory.
-			} else {
-				return true
-			}
-		}
-	}
-
-	for _, r := range modFile.Replace {
-		if r.New != i.replace[r.Old] {
-			return true
-		}
-	}
-
-	for _, x := range modFile.Exclude {
-		if !i.exclude[x.Mod] {
-			return true
-		}
-	}
-
-	return false
-}

src/cmd/go/internal/modload/load.go

@@ -9,14 +9,12 @@ import (
 	"errors"
 	"fmt"
 	"go/build"
-	"io/ioutil"
 	"os"
 	"path"
 	pathpkg "path"
 	"path/filepath"
 	"sort"
 	"strings"
-	"sync"
 
 	"cmd/go/internal/base"
 	"cmd/go/internal/cfg"
@@ -27,9 +25,7 @@ import (
 	"cmd/go/internal/search"
 	"cmd/go/internal/str"
 
-	"golang.org/x/mod/modfile"
 	"golang.org/x/mod/module"
-	"golang.org/x/mod/semver"
 )
 
 // buildList is the list of modules to use for building packages.
@@ -1033,354 +1029,3 @@ func WhyDepth(path string) int {
 	}
 	return n
 }
-
-// Replacement returns the replacement for mod, if any, from go.mod.
-// If there is no replacement for mod, Replacement returns
-// a module.Version with Path == "".
-func Replacement(mod module.Version) module.Version {
-	if index != nil {
-		if r, ok := index.replace[mod]; ok {
-			return r
-		}
-		if r, ok := index.replace[module.Version{Path: mod.Path}]; ok {
-			return r
-		}
-	}
-	return module.Version{}
-}
-
-// mvsReqs implements mvs.Reqs for module semantic versions,
-// with any exclusions or replacements applied internally.
-type mvsReqs struct {
-	buildList []module.Version
-	cache     par.Cache
-	versions  sync.Map
-}
-
-// Reqs returns the current module requirement graph.
-// Future calls to SetBuildList do not affect the operation
-// of the returned Reqs.
-func Reqs() mvs.Reqs {
-	r := &mvsReqs{
-		buildList: buildList,
-	}
-	return r
-}
-
-func (r *mvsReqs) Required(mod module.Version) ([]module.Version, error) {
-	type cached struct {
-		list []module.Version
-		err  error
-	}
-
-	c := r.cache.Do(mod, func() interface{} {
-		list, err := r.required(mod)
-		if err != nil {
-			return cached{nil, err}
-		}
-		for i, mv := range list {
-			if index != nil {
-				for index.exclude[mv] {
-					mv1, err := r.next(mv)
-					if err != nil {
-						return cached{nil, err}
-					}
-					if mv1.Version == "none" {
-						return cached{nil, fmt.Errorf("%s(%s) depends on excluded %s(%s) with no newer version available", mod.Path, mod.Version, mv.Path, mv.Version)}
-					}
-					mv = mv1
-				}
-			}
-			list[i] = mv
-		}
-
-		return cached{list, nil}
-	}).(cached)
-
-	return c.list, c.err
-}
-
-var vendorOnce sync.Once
-
-type vendorMetadata struct {
-	Explicit    bool
-	Replacement module.Version
-}
-
-var (
-	vendorList      []module.Version          // modules that contribute packages to the build, in order of appearance
-	vendorReplaced  []module.Version          // all replaced modules; may or may not also contribute packages
-	vendorVersion   map[string]string         // module path → selected version (if known)
-	vendorPkgModule map[string]module.Version // package → containing module
-	vendorMeta      map[module.Version]vendorMetadata
-)
-
-// readVendorList reads the list of vendored modules from vendor/modules.txt.
-func readVendorList() {
-	vendorOnce.Do(func() {
-		vendorList = nil
-		vendorPkgModule = make(map[string]module.Version)
-		vendorVersion = make(map[string]string)
-		vendorMeta = make(map[module.Version]vendorMetadata)
-		data, err := ioutil.ReadFile(filepath.Join(ModRoot(), "vendor/modules.txt"))
-		if err != nil {
-			if !errors.Is(err, os.ErrNotExist) {
-				base.Fatalf("go: %s", err)
-			}
-			return
-		}
-
-		var mod module.Version
-		for _, line := range strings.Split(string(data), "\n") {
-			if strings.HasPrefix(line, "# ") {
-				f := strings.Fields(line)
-
-				if len(f) < 3 {
-					continue
-				}
-				if semver.IsValid(f[2]) {
-					// A module, but we don't yet know whether it is in the build list or
-					// only included to indicate a replacement.
-					mod = module.Version{Path: f[1], Version: f[2]}
-					f = f[3:]
-				} else if f[2] == "=>" {
-					// A wildcard replacement found in the main module's go.mod file.
-					mod = module.Version{Path: f[1]}
-					f = f[2:]
-				} else {
-					// Not a version or a wildcard replacement.
-					// We don't know how to interpret this module line, so ignore it.
-					mod = module.Version{}
-					continue
-				}
-
-				if len(f) >= 2 && f[0] == "=>" {
-					meta := vendorMeta[mod]
-					if len(f) == 2 {
-						// File replacement.
-						meta.Replacement = module.Version{Path: f[1]}
-						vendorReplaced = append(vendorReplaced, mod)
-					} else if len(f) == 3 && semver.IsValid(f[2]) {
-						// Path and version replacement.
-						meta.Replacement = module.Version{Path: f[1], Version: f[2]}
-						vendorReplaced = append(vendorReplaced, mod)
-					} else {
-						// We don't understand this replacement. Ignore it.
-					}
-					vendorMeta[mod] = meta
-				}
-				continue
-			}
-
-			// Not a module line. Must be a package within a module or a metadata
-			// directive, either of which requires a preceding module line.
-			if mod.Path == "" {
-				continue
-			}
-
-			if strings.HasPrefix(line, "## ") {
-				// Metadata. Take the union of annotations across multiple lines, if present.
-				meta := vendorMeta[mod]
-				for _, entry := range strings.Split(strings.TrimPrefix(line, "## "), ";") {
-					entry = strings.TrimSpace(entry)
-					if entry == "explicit" {
-						meta.Explicit = true
-					}
-					// All other tokens are reserved for future use.
-				}
-				vendorMeta[mod] = meta
-				continue
-			}
-
-			if f := strings.Fields(line); len(f) == 1 && module.CheckImportPath(f[0]) == nil {
-				// A package within the current module.
-				vendorPkgModule[f[0]] = mod
-
-				// Since this module provides a package for the build, we know that it
-				// is in the build list and is the selected version of its path.
-				// If this information is new, record it.
-				if v, ok := vendorVersion[mod.Path]; !ok || semver.Compare(v, mod.Version) < 0 {
-					vendorList = append(vendorList, mod)
-					vendorVersion[mod.Path] = mod.Version
-				}
-			}
-		}
-	})
-}
-
-func (r *mvsReqs) modFileToList(f *modfile.File) []module.Version {
-	list := make([]module.Version, 0, len(f.Require))
-	for _, r := range f.Require {
-		list = append(list, r.Mod)
-	}
-	return list
-}
-
-// required returns a unique copy of the requirements of mod.
-func (r *mvsReqs) required(mod module.Version) ([]module.Version, error) {
-	if mod == Target {
-		if modFile != nil && modFile.Go != nil {
-			r.versions.LoadOrStore(mod, modFile.Go.Version)
-		}
-		return append([]module.Version(nil), r.buildList[1:]...), nil
-	}
-
-	if cfg.BuildMod == "vendor" {
-		// For every module other than the target,
-		// return the full list of modules from modules.txt.
-		readVendorList()
-		return append([]module.Version(nil), vendorList...), nil
-	}
-
-	origPath := mod.Path
-	if repl := Replacement(mod); repl.Path != "" {
-		if repl.Version == "" {
-			// TODO: need to slip the new version into the tags list etc.
-			dir := repl.Path
-			if !filepath.IsAbs(dir) {
-				dir = filepath.Join(ModRoot(), dir)
-			}
-			gomod := filepath.Join(dir, "go.mod")
-			data, err := ioutil.ReadFile(gomod)
-			if err != nil {
-				return nil, fmt.Errorf("parsing %s: %v", base.ShortPath(gomod), err)
-			}
-			f, err := modfile.ParseLax(gomod, data, nil)
-			if err != nil {
-				return nil, fmt.Errorf("parsing %s: %v", base.ShortPath(gomod), err)
-			}
-			if f.Go != nil {
-				r.versions.LoadOrStore(mod, f.Go.Version)
-			}
-			return r.modFileToList(f), nil
-		}
-		mod = repl
-	}
-
-	if mod.Version == "none" {
-		return nil, nil
-	}
-
-	if !semver.IsValid(mod.Version) {
-		// Disallow the broader queries supported by fetch.Lookup.
-		base.Fatalf("go: internal error: %s@%s: unexpected invalid semantic version", mod.Path, mod.Version)
-	}
-
-	data, err := modfetch.GoMod(mod.Path, mod.Version)
-	if err != nil {
-		return nil, err
-	}
-	f, err := modfile.ParseLax("go.mod", data, nil)
-	if err != nil {
-		return nil, module.VersionError(mod, fmt.Errorf("parsing go.mod: %v", err))
-	}
-
-	if f.Module == nil {
-		return nil, module.VersionError(mod, errors.New("parsing go.mod: missing module line"))
-	}
-	if mpath := f.Module.Mod.Path; mpath != origPath && mpath != mod.Path {
-		return nil, module.VersionError(mod, fmt.Errorf(`parsing go.mod:
-	module declares its path as: %s
-	        but was required as: %s`, mpath, mod.Path))
-	}
-	if f.Go != nil {
-		r.versions.LoadOrStore(mod, f.Go.Version)
-	}
-
-	return r.modFileToList(f), nil
-}
-
-func (*mvsReqs) Max(v1, v2 string) string {
-	if v1 != "" && semver.Compare(v1, v2) == -1 {
-		return v2
-	}
-	return v1
-}
-
-// Upgrade is a no-op, here to implement mvs.Reqs.
-// The upgrade logic for go get -u is in ../modget/get.go.
-func (*mvsReqs) Upgrade(m module.Version) (module.Version, error) {
-	return m, nil
-}
-
-func versions(path string) ([]string, error) {
-	// Note: modfetch.Lookup and repo.Versions are cached,
-	// so there's no need for us to add extra caching here.
-	var versions []string
-	err := modfetch.TryProxies(func(proxy string) error {
-		repo, err := modfetch.Lookup(proxy, path)
-		if err == nil {
-			versions, err = repo.Versions("")
-		}
-		return err
-	})
-	return versions, err
-}
-
-// Previous returns the tagged version of m.Path immediately prior to
-// m.Version, or version "none" if no prior version is tagged.
-func (*mvsReqs) Previous(m module.Version) (module.Version, error) {
-	list, err := versions(m.Path)
-	if err != nil {
-		return module.Version{}, err
-	}
-	i := sort.Search(len(list), func(i int) bool { return semver.Compare(list[i], m.Version) >= 0 })
-	if i > 0 {
-		return module.Version{Path: m.Path, Version: list[i-1]}, nil
-	}
-	return module.Version{Path: m.Path, Version: "none"}, nil
-}
-
-// next returns the next version of m.Path after m.Version.
-// It is only used by the exclusion processing in the Required method,
-// not called directly by MVS.
-func (*mvsReqs) next(m module.Version) (module.Version, error) {
-	list, err := versions(m.Path)
-	if err != nil {
-		return module.Version{}, err
-	}
-	i := sort.Search(len(list), func(i int) bool { return semver.Compare(list[i], m.Version) > 0 })
-	if i < len(list) {
-		return module.Version{Path: m.Path, Version: list[i]}, nil
-	}
-	return module.Version{Path: m.Path, Version: "none"}, nil
-}
-
-// fetch downloads the given module (or its replacement)
-// and returns its location.
-//
-// The isLocal return value reports whether the replacement,
-// if any, is local to the filesystem.
-func fetch(mod module.Version) (dir string, isLocal bool, err error) {
-	if mod == Target {
-		return ModRoot(), true, nil
-	}
-	if r := Replacement(mod); r.Path != "" {
-		if r.Version == "" {
-			dir = r.Path
-			if !filepath.IsAbs(dir) {
-				dir = filepath.Join(ModRoot(), dir)
-			}
-			// Ensure that the replacement directory actually exists:
-			// dirInModule does not report errors for missing modules,
-			// so if we don't report the error now, later failures will be
-			// very mysterious.
-			if _, err := os.Stat(dir); err != nil {
-				if os.IsNotExist(err) {
-					// Semantically the module version itself “exists” — we just don't
-					// have its source code. Remove the equivalence to os.ErrNotExist,
-					// and make the message more concise while we're at it.
-					err = fmt.Errorf("replacement directory %s does not exist", r.Path)
-				} else {
-					err = fmt.Errorf("replacement directory %s: %w", r.Path, err)
-				}
-				return dir, true, module.VersionError(mod, err)
-			}
-			return dir, true, nil
-		}
-		mod = r
-	}
-
-	dir, err = modfetch.Download(mod)
-	return dir, false, err
-}

src/cmd/go/internal/modload/modfile.go

@@ -0,0 +1,164 @@
+// Copyright 2020 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.
+
+package modload
+
+import (
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+
+	"golang.org/x/mod/modfile"
+	"golang.org/x/mod/module"
+)
+
+var modFile *modfile.File
+
+// A modFileIndex is an index of data corresponding to a modFile
+// at a specific point in time.
+type modFileIndex struct {
+	data         []byte
+	dataNeedsFix bool // true if fixVersion applied a change while parsing data
+	module       module.Version
+	goVersion    string
+	require      map[module.Version]requireMeta
+	replace      map[module.Version]module.Version
+	exclude      map[module.Version]bool
+}
+
+// index is the index of the go.mod file as of when it was last read or written.
+var index *modFileIndex
+
+type requireMeta struct {
+	indirect bool
+}
+
+// Allowed reports whether module m is allowed (not excluded) by the main module's go.mod.
+func Allowed(m module.Version) bool {
+	return index == nil || !index.exclude[m]
+}
+
+// Replacement returns the replacement for mod, if any, from go.mod.
+// If there is no replacement for mod, Replacement returns
+// a module.Version with Path == "".
+func Replacement(mod module.Version) module.Version {
+	if index != nil {
+		if r, ok := index.replace[mod]; ok {
+			return r
+		}
+		if r, ok := index.replace[module.Version{Path: mod.Path}]; ok {
+			return r
+		}
+	}
+	return module.Version{}
+}
+
+// indexModFile rebuilds the index of modFile.
+// If modFile has been changed since it was first read,
+// modFile.Cleanup must be called before indexModFile.
+func indexModFile(data []byte, modFile *modfile.File, needsFix bool) *modFileIndex {
+	i := new(modFileIndex)
+	i.data = data
+	i.dataNeedsFix = needsFix
+
+	i.module = module.Version{}
+	if modFile.Module != nil {
+		i.module = modFile.Module.Mod
+	}
+
+	i.goVersion = ""
+	if modFile.Go != nil {
+		i.goVersion = modFile.Go.Version
+	}
+
+	i.require = make(map[module.Version]requireMeta, len(modFile.Require))
+	for _, r := range modFile.Require {
+		i.require[r.Mod] = requireMeta{indirect: r.Indirect}
+	}
+
+	i.replace = make(map[module.Version]module.Version, len(modFile.Replace))
+	for _, r := range modFile.Replace {
+		if prev, dup := i.replace[r.Old]; dup && prev != r.New {
+			base.Fatalf("go: conflicting replacements for %v:\n\t%v\n\t%v", r.Old, prev, r.New)
+		}
+		i.replace[r.Old] = r.New
+	}
+
+	i.exclude = make(map[module.Version]bool, len(modFile.Exclude))
+	for _, x := range modFile.Exclude {
+		i.exclude[x.Mod] = true
+	}
+
+	return i
+}
+
+// modFileIsDirty reports whether the go.mod file differs meaningfully
+// from what was indexed.
+// If modFile has been changed (even cosmetically) since it was first read,
+// modFile.Cleanup must be called before modFileIsDirty.
+func (i *modFileIndex) modFileIsDirty(modFile *modfile.File) bool {
+	if i == nil {
+		return modFile != nil
+	}
+
+	if i.dataNeedsFix {
+		return true
+	}
+
+	if modFile.Module == nil {
+		if i.module != (module.Version{}) {
+			return true
+		}
+	} else if modFile.Module.Mod != i.module {
+		return true
+	}
+
+	if modFile.Go == nil {
+		if i.goVersion != "" {
+			return true
+		}
+	} else if modFile.Go.Version != i.goVersion {
+		if i.goVersion == "" && cfg.BuildMod == "readonly" {
+			// go.mod files did not always require a 'go' version, so do not error out
+			// if one is missing — we may be inside an older module in the module
+			// cache, and should bias toward providing useful behavior.
+		} else {
+			return true
+		}
+	}
+
+	if len(modFile.Require) != len(i.require) ||
+		len(modFile.Replace) != len(i.replace) ||
+		len(modFile.Exclude) != len(i.exclude) {
+		return true
+	}
+
+	for _, r := range modFile.Require {
+		if meta, ok := i.require[r.Mod]; !ok {
+			return true
+		} else if r.Indirect != meta.indirect {
+			if cfg.BuildMod == "readonly" {
+				// The module's requirements are consistent; only the "// indirect"
+				// comments that are wrong. But those are only guaranteed to be accurate
+				// after a "go mod tidy" — it's a good idea to run those before
+				// committing a change, but it's certainly not mandatory.
+			} else {
+				return true
+			}
+		}
+	}
+
+	for _, r := range modFile.Replace {
+		if r.New != i.replace[r.Old] {
+			return true
+		}
+	}
+
+	for _, x := range modFile.Exclude {
+		if !i.exclude[x.Mod] {
+			return true
+		}
+	}
+
+	return false
+}

src/cmd/go/internal/modload/mvs.go

@@ -0,0 +1,253 @@
+// Copyright 2020 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.
+
+package modload
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"sort"
+	"sync"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/modfetch"
+	"cmd/go/internal/mvs"
+	"cmd/go/internal/par"
+
+	"golang.org/x/mod/modfile"
+	"golang.org/x/mod/module"
+	"golang.org/x/mod/semver"
+)
+
+// mvsReqs implements mvs.Reqs for module semantic versions,
+// with any exclusions or replacements applied internally.
+type mvsReqs struct {
+	buildList []module.Version
+	cache     par.Cache
+	versions  sync.Map
+}
+
+// Reqs returns the current module requirement graph.
+// Future calls to SetBuildList do not affect the operation
+// of the returned Reqs.
+func Reqs() mvs.Reqs {
+	r := &mvsReqs{
+		buildList: buildList,
+	}
+	return r
+}
+
+func (r *mvsReqs) Required(mod module.Version) ([]module.Version, error) {
+	type cached struct {
+		list []module.Version
+		err  error
+	}
+
+	c := r.cache.Do(mod, func() interface{} {
+		list, err := r.required(mod)
+		if err != nil {
+			return cached{nil, err}
+		}
+		for i, mv := range list {
+			if index != nil {
+				for index.exclude[mv] {
+					mv1, err := r.next(mv)
+					if err != nil {
+						return cached{nil, err}
+					}
+					if mv1.Version == "none" {
+						return cached{nil, fmt.Errorf("%s(%s) depends on excluded %s(%s) with no newer version available", mod.Path, mod.Version, mv.Path, mv.Version)}
+					}
+					mv = mv1
+				}
+			}
+			list[i] = mv
+		}
+
+		return cached{list, nil}
+	}).(cached)
+
+	return c.list, c.err
+}
+
+func (r *mvsReqs) modFileToList(f *modfile.File) []module.Version {
+	list := make([]module.Version, 0, len(f.Require))
+	for _, r := range f.Require {
+		list = append(list, r.Mod)
+	}
+	return list
+}
+
+// required returns a unique copy of the requirements of mod.
+func (r *mvsReqs) required(mod module.Version) ([]module.Version, error) {
+	if mod == Target {
+		if modFile != nil && modFile.Go != nil {
+			r.versions.LoadOrStore(mod, modFile.Go.Version)
+		}
+		return append([]module.Version(nil), r.buildList[1:]...), nil
+	}
+
+	if cfg.BuildMod == "vendor" {
+		// For every module other than the target,
+		// return the full list of modules from modules.txt.
+		readVendorList()
+		return append([]module.Version(nil), vendorList...), nil
+	}
+
+	origPath := mod.Path
+	if repl := Replacement(mod); repl.Path != "" {
+		if repl.Version == "" {
+			// TODO: need to slip the new version into the tags list etc.
+			dir := repl.Path
+			if !filepath.IsAbs(dir) {
+				dir = filepath.Join(ModRoot(), dir)
+			}
+			gomod := filepath.Join(dir, "go.mod")
+			data, err := ioutil.ReadFile(gomod)
+			if err != nil {
+				return nil, fmt.Errorf("parsing %s: %v", base.ShortPath(gomod), err)
+			}
+			f, err := modfile.ParseLax(gomod, data, nil)
+			if err != nil {
+				return nil, fmt.Errorf("parsing %s: %v", base.ShortPath(gomod), err)
+			}
+			if f.Go != nil {
+				r.versions.LoadOrStore(mod, f.Go.Version)
+			}
+			return r.modFileToList(f), nil
+		}
+		mod = repl
+	}
+
+	if mod.Version == "none" {
+		return nil, nil
+	}
+
+	if !semver.IsValid(mod.Version) {
+		// Disallow the broader queries supported by fetch.Lookup.
+		base.Fatalf("go: internal error: %s@%s: unexpected invalid semantic version", mod.Path, mod.Version)
+	}
+
+	data, err := modfetch.GoMod(mod.Path, mod.Version)
+	if err != nil {
+		return nil, err
+	}
+	f, err := modfile.ParseLax("go.mod", data, nil)
+	if err != nil {
+		return nil, module.VersionError(mod, fmt.Errorf("parsing go.mod: %v", err))
+	}
+
+	if f.Module == nil {
+		return nil, module.VersionError(mod, errors.New("parsing go.mod: missing module line"))
+	}
+	if mpath := f.Module.Mod.Path; mpath != origPath && mpath != mod.Path {
+		return nil, module.VersionError(mod, fmt.Errorf(`parsing go.mod:
+	module declares its path as: %s
+	        but was required as: %s`, mpath, mod.Path))
+	}
+	if f.Go != nil {
+		r.versions.LoadOrStore(mod, f.Go.Version)
+	}
+
+	return r.modFileToList(f), nil
+}
+
+func (*mvsReqs) Max(v1, v2 string) string {
+	if v1 != "" && semver.Compare(v1, v2) == -1 {
+		return v2
+	}
+	return v1
+}
+
+// Upgrade is a no-op, here to implement mvs.Reqs.
+// The upgrade logic for go get -u is in ../modget/get.go.
+func (*mvsReqs) Upgrade(m module.Version) (module.Version, error) {
+	return m, nil
+}
+
+func versions(path string) ([]string, error) {
+	// Note: modfetch.Lookup and repo.Versions are cached,
+	// so there's no need for us to add extra caching here.
+	var versions []string
+	err := modfetch.TryProxies(func(proxy string) error {
+		repo, err := modfetch.Lookup(proxy, path)
+		if err == nil {
+			versions, err = repo.Versions("")
+		}
+		return err
+	})
+	return versions, err
+}
+
+// Previous returns the tagged version of m.Path immediately prior to
+// m.Version, or version "none" if no prior version is tagged.
+func (*mvsReqs) Previous(m module.Version) (module.Version, error) {
+	list, err := versions(m.Path)
+	if err != nil {
+		return module.Version{}, err
+	}
+	i := sort.Search(len(list), func(i int) bool { return semver.Compare(list[i], m.Version) >= 0 })
+	if i > 0 {
+		return module.Version{Path: m.Path, Version: list[i-1]}, nil
+	}
+	return module.Version{Path: m.Path, Version: "none"}, nil
+}
+
+// next returns the next version of m.Path after m.Version.
+// It is only used by the exclusion processing in the Required method,
+// not called directly by MVS.
+func (*mvsReqs) next(m module.Version) (module.Version, error) {
+	list, err := versions(m.Path)
+	if err != nil {
+		return module.Version{}, err
+	}
+	i := sort.Search(len(list), func(i int) bool { return semver.Compare(list[i], m.Version) > 0 })
+	if i < len(list) {
+		return module.Version{Path: m.Path, Version: list[i]}, nil
+	}
+	return module.Version{Path: m.Path, Version: "none"}, nil
+}
+
+// fetch downloads the given module (or its replacement)
+// and returns its location.
+//
+// The isLocal return value reports whether the replacement,
+// if any, is local to the filesystem.
+func fetch(mod module.Version) (dir string, isLocal bool, err error) {
+	if mod == Target {
+		return ModRoot(), true, nil
+	}
+	if r := Replacement(mod); r.Path != "" {
+		if r.Version == "" {
+			dir = r.Path
+			if !filepath.IsAbs(dir) {
+				dir = filepath.Join(ModRoot(), dir)
+			}
+			// Ensure that the replacement directory actually exists:
+			// dirInModule does not report errors for missing modules,
+			// so if we don't report the error now, later failures will be
+			// very mysterious.
+			if _, err := os.Stat(dir); err != nil {
+				if os.IsNotExist(err) {
+					// Semantically the module version itself “exists” — we just don't
+					// have its source code. Remove the equivalence to os.ErrNotExist,
+					// and make the message more concise while we're at it.
+					err = fmt.Errorf("replacement directory %s does not exist", r.Path)
+				} else {
+					err = fmt.Errorf("replacement directory %s: %w", r.Path, err)
+				}
+				return dir, true, module.VersionError(mod, err)
+			}
+			return dir, true, nil
+		}
+		mod = r
+	}
+
+	dir, err = modfetch.Download(mod)
+	return dir, false, err
+}

src/cmd/go/internal/modload/vendor.go

@@ -0,0 +1,217 @@
+// Copyright 2020 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.
+
+package modload
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+
+	"cmd/go/internal/base"
+
+	"golang.org/x/mod/module"
+	"golang.org/x/mod/semver"
+)
+
+var (
+	vendorOnce      sync.Once
+	vendorList      []module.Version          // modules that contribute packages to the build, in order of appearance
+	vendorReplaced  []module.Version          // all replaced modules; may or may not also contribute packages
+	vendorVersion   map[string]string         // module path → selected version (if known)
+	vendorPkgModule map[string]module.Version // package → containing module
+	vendorMeta      map[module.Version]vendorMetadata
+)
+
+type vendorMetadata struct {
+	Explicit    bool
+	Replacement module.Version
+}
+
+// readVendorList reads the list of vendored modules from vendor/modules.txt.
+func readVendorList() {
+	vendorOnce.Do(func() {
+		vendorList = nil
+		vendorPkgModule = make(map[string]module.Version)
+		vendorVersion = make(map[string]string)
+		vendorMeta = make(map[module.Version]vendorMetadata)
+		data, err := ioutil.ReadFile(filepath.Join(ModRoot(), "vendor/modules.txt"))
+		if err != nil {
+			if !errors.Is(err, os.ErrNotExist) {
+				base.Fatalf("go: %s", err)
+			}
+			return
+		}
+
+		var mod module.Version
+		for _, line := range strings.Split(string(data), "\n") {
+			if strings.HasPrefix(line, "# ") {
+				f := strings.Fields(line)
+
+				if len(f) < 3 {
+					continue
+				}
+				if semver.IsValid(f[2]) {
+					// A module, but we don't yet know whether it is in the build list or
+					// only included to indicate a replacement.
+					mod = module.Version{Path: f[1], Version: f[2]}
+					f = f[3:]
+				} else if f[2] == "=>" {
+					// A wildcard replacement found in the main module's go.mod file.
+					mod = module.Version{Path: f[1]}
+					f = f[2:]
+				} else {
+					// Not a version or a wildcard replacement.
+					// We don't know how to interpret this module line, so ignore it.
+					mod = module.Version{}
+					continue
+				}
+
+				if len(f) >= 2 && f[0] == "=>" {
+					meta := vendorMeta[mod]
+					if len(f) == 2 {
+						// File replacement.
+						meta.Replacement = module.Version{Path: f[1]}
+						vendorReplaced = append(vendorReplaced, mod)
+					} else if len(f) == 3 && semver.IsValid(f[2]) {
+						// Path and version replacement.
+						meta.Replacement = module.Version{Path: f[1], Version: f[2]}
+						vendorReplaced = append(vendorReplaced, mod)
+					} else {
+						// We don't understand this replacement. Ignore it.
+					}
+					vendorMeta[mod] = meta
+				}
+				continue
+			}
+
+			// Not a module line. Must be a package within a module or a metadata
+			// directive, either of which requires a preceding module line.
+			if mod.Path == "" {
+				continue
+			}
+
+			if strings.HasPrefix(line, "## ") {
+				// Metadata. Take the union of annotations across multiple lines, if present.
+				meta := vendorMeta[mod]
+				for _, entry := range strings.Split(strings.TrimPrefix(line, "## "), ";") {
+					entry = strings.TrimSpace(entry)
+					if entry == "explicit" {
+						meta.Explicit = true
+					}
+					// All other tokens are reserved for future use.
+				}
+				vendorMeta[mod] = meta
+				continue
+			}
+
+			if f := strings.Fields(line); len(f) == 1 && module.CheckImportPath(f[0]) == nil {
+				// A package within the current module.
+				vendorPkgModule[f[0]] = mod
+
+				// Since this module provides a package for the build, we know that it
+				// is in the build list and is the selected version of its path.
+				// If this information is new, record it.
+				if v, ok := vendorVersion[mod.Path]; !ok || semver.Compare(v, mod.Version) < 0 {
+					vendorList = append(vendorList, mod)
+					vendorVersion[mod.Path] = mod.Version
+				}
+			}
+		}
+	})
+}
+
+// checkVendorConsistency verifies that the vendor/modules.txt file matches (if
+// go 1.14) or at least does not contradict (go 1.13 or earlier) the
+// requirements and replacements listed in the main module's go.mod file.
+func checkVendorConsistency() {
+	readVendorList()
+
+	pre114 := false
+	if modFile.Go == nil || semver.Compare("v"+modFile.Go.Version, "v1.14") < 0 {
+		// Go versions before 1.14 did not include enough information in
+		// vendor/modules.txt to check for consistency.
+		// If we know that we're on an earlier version, relax the consistency check.
+		pre114 = true
+	}
+
+	vendErrors := new(strings.Builder)
+	vendErrorf := func(mod module.Version, format string, args ...interface{}) {
+		detail := fmt.Sprintf(format, args...)
+		if mod.Version == "" {
+			fmt.Fprintf(vendErrors, "\n\t%s: %s", mod.Path, detail)
+		} else {
+			fmt.Fprintf(vendErrors, "\n\t%s@%s: %s", mod.Path, mod.Version, detail)
+		}
+	}
+
+	for _, r := range modFile.Require {
+		if !vendorMeta[r.Mod].Explicit {
+			if pre114 {
+				// Before 1.14, modules.txt did not indicate whether modules were listed
+				// explicitly in the main module's go.mod file.
+				// However, we can at least detect a version mismatch if packages were
+				// vendored from a non-matching version.
+				if vv, ok := vendorVersion[r.Mod.Path]; ok && vv != r.Mod.Version {
+					vendErrorf(r.Mod, fmt.Sprintf("is explicitly required in go.mod, but vendor/modules.txt indicates %s@%s", r.Mod.Path, vv))
+				}
+			} else {
+				vendErrorf(r.Mod, "is explicitly required in go.mod, but not marked as explicit in vendor/modules.txt")
+			}
+		}
+	}
+
+	describe := func(m module.Version) string {
+		if m.Version == "" {
+			return m.Path
+		}
+		return m.Path + "@" + m.Version
+	}
+
+	// We need to verify *all* replacements that occur in modfile: even if they
+	// don't directly apply to any module in the vendor list, the replacement
+	// go.mod file can affect the selected versions of other (transitive)
+	// dependencies
+	for _, r := range modFile.Replace {
+		vr := vendorMeta[r.Old].Replacement
+		if vr == (module.Version{}) {
+			if pre114 && (r.Old.Version == "" || vendorVersion[r.Old.Path] != r.Old.Version) {
+				// Before 1.14, modules.txt omitted wildcard replacements and
+				// replacements for modules that did not have any packages to vendor.
+			} else {
+				vendErrorf(r.Old, "is replaced in go.mod, but not marked as replaced in vendor/modules.txt")
+			}
+		} else if vr != r.New {
+			vendErrorf(r.Old, "is replaced by %s in go.mod, but marked as replaced by %s in vendor/modules.txt", describe(r.New), describe(vr))
+		}
+	}
+
+	for _, mod := range vendorList {
+		meta := vendorMeta[mod]
+		if meta.Explicit {
+			if _, inGoMod := index.require[mod]; !inGoMod {
+				vendErrorf(mod, "is marked as explicit in vendor/modules.txt, but not explicitly required in go.mod")
+			}
+		}
+	}
+
+	for _, mod := range vendorReplaced {
+		r := Replacement(mod)
+		if r == (module.Version{}) {
+			vendErrorf(mod, "is marked as replaced in vendor/modules.txt, but not replaced in go.mod")
+			continue
+		}
+		if meta := vendorMeta[mod]; r != meta.Replacement {
+			vendErrorf(mod, "is marked as replaced by %s in vendor/modules.txt, but replaced by %s in go.mod", describe(meta.Replacement), describe(r))
+		}
+	}
+
+	if vendErrors.Len() > 0 {
+		base.Fatalf("go: inconsistent vendoring in %s:%s\n\nrun 'go mod vendor' to sync, or use -mod=mod or -mod=readonly to ignore the vendor directory", modRoot, vendErrors)
+	}
+}

src/cmd/go/internal/robustio/robustio_flaky.go

@@ -15,7 +15,7 @@ import (
 	"time"
 )
 
-const arbitraryTimeout = 500 * time.Millisecond
+const arbitraryTimeout = 2000 * time.Millisecond
 
 // retry retries ephemeral errors from f up to an arbitrary timeout
 // to work around filesystem flakiness on Windows and Darwin.

src/cmd/go/internal/work/exec.go

@@ -213,6 +213,9 @@ func (b *Builder) buildActionID(a *Action) cache.ActionID {
 	} else if cfg.BuildTrimpath && p.Module != nil {
 		fmt.Fprintf(h, "module %s@%s\n", p.Module.Path, p.Module.Version)
 	}
+	if p.Module != nil {
+		fmt.Fprintf(h, "go %s\n", p.Module.GoVersion)
+	}
 	fmt.Fprintf(h, "goos %s goarch %s\n", cfg.Goos, cfg.Goarch)
 	fmt.Fprintf(h, "import %q\n", p.ImportPath)
 	fmt.Fprintf(h, "omitdebug %v standard %v local %v prefix %q\n", p.Internal.OmitDebug, p.Standard, p.Internal.Local, p.Internal.LocalPrefix)

src/cmd/go/script_test.go

@@ -109,6 +109,7 @@ func (ts *testScript) setup() {
 		"CCACHE_DISABLE=1", // ccache breaks with non-existent HOME
 		"GOARCH=" + runtime.GOARCH,
 		"GOCACHE=" + testGOCACHE,
+		"GODEBUG=" + os.Getenv("GODEBUG"),
 		"GOEXE=" + cfg.ExeSuffix,
 		"GOOS=" + runtime.GOOS,
 		"GOPATH=" + filepath.Join(ts.workdir, "gopath"),

src/cmd/go/testdata/script/README

@@ -36,6 +36,7 @@ Scripts also have access to these other environment variables:
 	HOME=/no-home
 	PATH=<actual PATH>
 	TMPDIR=$WORK/tmp
+	GODEBUG=<actual GODEBUG>
 	devnull=<value of os.DevNull>
 	goversion=<current Go version; for example, 1.12>
 	:=<OS-specific path list separator>

src/cmd/go/testdata/script/build_gcflags.txt

@@ -7,7 +7,8 @@ env GO111MODULE=off
 [!linux] skip  # test only works if c-archive implies -shared
 [short] skip
 
-go build -x -buildmode=c-archive -gcflags=all=-shared=false ./override.go
+env GOCACHE=$WORK/gocache  # Looking for compile commands, so need a clean cache.
+go build -x -n -buildmode=c-archive -gcflags=all=-shared=false ./override.go
 stderr '^.*/compile (.* )?-shared (.* )?-shared=false'
 
 -- override.go --

src/cmd/go/testdata/script/cgo_flag_contains_space.txt

@@ -1,15 +1,16 @@
 [short] skip
 [!cgo] skip
 
-go run -x main.go
+env GOCACHE=$WORK/gocache  # Looking for compile flags, so need a clean cache.
+go build -x -n main.go
 stderr '"-I[^"]+c flags"' # find quoted c flags
-! stderr '"-I[^"]+c flags".*"-I[^"]+c flags"' # don't find too many quoted c flags
+! stderr '"-I[^"]+c flags".*"-I[^"]+c flags"' # don't find too many quoted c flags per line
 stderr '"-L[^"]+ld flags"' # find quoted ld flags
-! stderr '"-L[^"]+c flags".*"-L[^"]+c flags"' # don't find too many quoted ld flags
+! stderr '"-L[^"]+c flags".*"-L[^"]+c flags"' # don't find too many quoted ld flags per line
 
 -- main.go --
 package main
 // #cgo CFLAGS: -I"c flags"
 // #cgo LDFLAGS: -L"ld flags"
 import "C"
-func main() {}
+func main() {}

src/cmd/go/testdata/script/cover_blank_func_decl.txt

@@ -0,0 +1,31 @@
+[short] skip
+go test -cover ./coverblank
+stdout 'coverage: 100.0% of statements'
+
+
+-- coverblank/a.go --
+package coverblank
+
+func _() {
+	println("unreachable")
+}
+
+type X int
+
+func (x X) Print() {
+	println(x)
+}
+
+func (x X) _() {
+	println("unreachable")
+}
+
+-- coverblank/a_test.go --
+package coverblank
+
+import "testing"
+
+func TestX(t *testing.T) {
+	var x X
+	x.Print()
+}

src/cmd/go/testdata/script/gcflags_patterns.txt

@@ -3,6 +3,8 @@ env GO111MODULE=off
 [!gc] skip 'using -gcflags and -ldflags'
 [short] skip
 
+env GOCACHE=$WORK/gocache  # Looking for compile commands, so need a clean cache.
+
 # -gcflags=-e applies to named packages, not dependencies
 go build -n -v -gcflags=-e z1 z2
 stderr 'compile.* -e.* -p z1'

src/cmd/go/testdata/script/mod_concurrent_unzipinplace.txt

@@ -0,0 +1,17 @@
+# This tests checks the GODEBUG=modcacheunzipinplace=1 flag, used as part of
+# a migration in golang.org/issue/36568.
+#
+# Concurrent downloads with and without GODEBUG=modcacheunzipinplace=1 should
+# not conflict. This is meant to simulate an old version and a new version
+# of Go accessing the cache concurrently.
+go mod download &
+env GODEBUG=modcacheunzipinplace=1
+go mod download
+wait
+
+-- go.mod --
+module golang.org/issue/36568
+
+go 1.14
+
+require rsc.io/quote v1.5.2

src/cmd/go/testdata/script/mod_download_concurrent_read.txt

@@ -0,0 +1,120 @@
+# This test simulates a process watching for changes and reading files in
+# module cache as a module is extracted.
+#
+# By default, we unzip a downloaded module into a temporary directory with a
+# random name, then rename the directory into place. On Windows, this fails
+# with ERROR_ACCESS_DENIED if another process (e.g., antivirus) opens files
+# in the directory.
+#
+# Setting GODEBUG=modcacheunzipinplace=1 opts into new behavior: a downloaded
+# module is unzipped in place. A .partial file is created elsewhere to indicate
+# that the extraction is incomplete.
+#
+# Verifies golang.org/issue/36568.
+
+[!windows] skip
+[short] skip
+
+# Control case: check that the default behavior fails.
+# This is commented out to avoid flakiness. We can't reproduce the failure
+# 100% of the time.
+# ! go run downloader.go
+
+# Experiment: check that the new behavior does not fail.
+env GODEBUG=modcacheunzipinplace=1
+go run downloader.go
+
+-- go.mod --
+module example.com/m
+
+go 1.14
+
+-- downloader.go --
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+)
+
+func main() {
+	if err := run(); err != nil {
+		log.Fatal(err)
+	}
+}
+
+// run repeatedly downloads a module while opening files in the module cache
+// in a background goroutine.
+//
+// run uses a different temporary module cache in each iteration so that we
+// don't need to clean the cache or synchronize closing files after each
+// iteration.
+func run() (err error) {
+	tmpDir, err := ioutil.TempDir("", "")
+	if err != nil {
+		return err
+	}
+	defer func() {
+		if rmErr := os.RemoveAll(tmpDir); err == nil && rmErr != nil {
+			err = rmErr
+		}
+	}()
+	for i := 0; i < 10; i++ {
+    gopath := filepath.Join(tmpDir, fmt.Sprintf("gopath%d", i))
+		var err error
+		done := make(chan struct{})
+		go func() {
+			err = download(gopath)
+			close(done)
+		}()
+		readCache(gopath, done)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// download downloads a module into the given cache using 'go mod download'.
+func download(gopath string) error {
+	cmd := exec.Command("go", "mod", "download", "-modcacherw", "rsc.io/quote@v1.5.2")
+	cmd.Stderr = os.Stderr
+	cmd.Env = append(os.Environ(), "GOPATH="+gopath)
+	return cmd.Run()
+}
+
+// readCache repeatedly globs for go.mod files in the given cache, then opens
+// those files for reading. When the done chan is closed, readCache closes
+// files and returns.
+func readCache(gopath string, done <-chan struct{}) {
+	files := make(map[string]*os.File)
+	defer func() {
+		for _, f := range files {
+			f.Close()
+		}
+	}()
+
+	pattern := filepath.Join(gopath, "pkg/mod/rsc.io/quote@v1.5.2*/go.mod")
+	for {
+		select {
+		case <-done:
+			return
+		default:
+		}
+
+		names, _ := filepath.Glob(pattern)
+		for _, name := range names {
+			if files[name] != nil {
+				continue
+			}
+			f, _ := os.Open(name)
+			if f != nil {
+				files[name] = f
+			}
+		}
+	}
+}

src/cmd/go/testdata/script/mod_download_partial.txt

@@ -0,0 +1,64 @@
+# Download a module
+go mod download -modcacherw rsc.io/quote
+exists $GOPATH/pkg/mod/rsc.io/quote@v1.5.2/go.mod
+
+# 'go mod verify' should fail if we delete a file.
+go mod verify
+rm $GOPATH/pkg/mod/rsc.io/quote@v1.5.2/go.mod
+! go mod verify
+
+# Create a .partial file to simulate an failure extracting the zip file.
+cp empty $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.2.partial
+
+# 'go mod verify' should not fail, since the module hasn't been completely
+# ingested into the cache.
+go mod verify
+
+# 'go list' should not load packages from the directory.
+# NOTE: the message "directory $dir outside available modules" is reported
+# for directories not in the main module, active modules in the module cache,
+# or local replacements. In this case, the directory is in the right place,
+# but it's incomplete, so 'go list' acts as if it's not an active module.
+! go list $GOPATH/pkg/mod/rsc.io/quote@v1.5.2
+stderr 'outside available modules'
+
+# 'go list -m' should not print the directory.
+go list -m -f '{{.Dir}}' rsc.io/quote
+! stdout .
+
+# 'go mod download' should re-extract the module and remove the .partial file.
+go mod download -modcacherw rsc.io/quote
+! exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.2.partial
+exists $GOPATH/pkg/mod/rsc.io/quote@v1.5.2/go.mod
+
+# 'go list' should succeed.
+go list $GOPATH/pkg/mod/rsc.io/quote@v1.5.2
+stdout '^rsc.io/quote$'
+
+# 'go list -m' should print the directory.
+go list -m -f '{{.Dir}}' rsc.io/quote
+stdout 'pkg[/\\]mod[/\\]rsc.io[/\\]quote@v1.5.2'
+
+# go mod verify should fail if we delete a file.
+go mod verify
+rm $GOPATH/pkg/mod/rsc.io/quote@v1.5.2/go.mod
+! go mod verify
+
+# 'go mod download' should not leave behind a directory or a .partial file
+# if there is an error extracting the zip file.
+env GODEBUG=modcacheunzipinplace=1
+rm $GOPATH/pkg/mod/rsc.io/quote@v1.5.2
+cp empty $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.2.zip
+! go mod download
+stderr 'not a valid zip file'
+! exists $GOPATH/pkg/mod/rsc.io/quote@v1.5.2
+! exists $GOPATH/pkg/mod/cache/download/rsc.io/quote/@v/v1.5.2.partial
+
+-- go.mod --
+module m
+
+go 1.14
+
+require rsc.io/quote v1.5.2
+
+-- empty --

src/cmd/go/testdata/script/mod_edit_go.txt

@@ -7,6 +7,13 @@ go mod edit -go=1.9
 grep 'go 1.9' go.mod
 go build
 
+# Reverting the version should force a rebuild and error instead of using
+# the cached 1.9 build. (https://golang.org/issue/37804)
+go mod edit -go=1.8
+! go build
+stderr 'type aliases only supported as of'
+
+
 -- go.mod --
 module m
 go 1.8

src/cmd/go/testdata/script/mod_get_commit.txt

@@ -14,6 +14,9 @@ go get -d golang.org/x/text@14c0d48
 
 # dropping -d, we should see a build.
 [short] skip
+
+env GOCACHE=$WORK/gocache  # Looking for compile commands, so need a clean cache.
+
 go get -x golang.org/x/text/language@14c0d48
 stderr 'compile|cp|gccgo .*language\.a$'
 

src/cmd/go/testdata/script/mod_get_tags.txt

@@ -14,7 +14,8 @@ stdout 'rsc.io/quote v1.5.2'
 [short] skip
 
 # Packages that are only imported in excluded files should not be built.
-go get -x .
+env GOCACHE=$WORK/gocache  # Looking for compile commands, so need a clean cache.
+go get -n -x .
 stderr 'compile.* -p m '
 ! stderr 'compile.* -p example.com/version '
 ! stderr 'compile.* -p rsc.io/quote '

src/cmd/go/testdata/script/mod_invalid_version.txt

@@ -76,17 +76,17 @@ cp go.mod.orig go.mod
 go mod edit -require golang.org/x/text@v0.1.1-0.20190915032832-14c0d48ead0c
 cd outside
 ! go list -m golang.org/x/text
-stderr 'go: example.com@v0.0.0 requires\n\tgolang.org/x/text@v0.1.1-0.20190915032832-14c0d48ead0c: invalid pseudo-version: does not match version-control timestamp \(2017-09-15T03:28:32Z\)'
+stderr 'go: example.com@v0.0.0 requires\n\tgolang.org/x/text@v0.1.1-0.20190915032832-14c0d48ead0c: invalid pseudo-version: does not match version-control timestamp \(expected 20170915032832\)'
 cd ..
 ! go list -m golang.org/x/text
-stderr 'golang.org/x/text@v0.1.1-0.20190915032832-14c0d48ead0c: invalid pseudo-version: does not match version-control timestamp \(2017-09-15T03:28:32Z\)'
+stderr 'golang.org/x/text@v0.1.1-0.20190915032832-14c0d48ead0c: invalid pseudo-version: does not match version-control timestamp \(expected 20170915032832\)'
 
 # A 'replace' directive in the main module can replace an invalid timestamp
 # with a valid one.
 go mod edit -replace golang.org/x/text@v0.1.1-0.20190915032832-14c0d48ead0c=golang.org/x/text@14c0d48ead0c
 cd outside
 ! go list -m golang.org/x/text
-stderr 'go: example.com@v0.0.0 requires\n\tgolang.org/x/text@v0.1.1-0.20190915032832-14c0d48ead0c: invalid pseudo-version: does not match version-control timestamp \(2017-09-15T03:28:32Z\)'
+stderr 'go: example.com@v0.0.0 requires\n\tgolang.org/x/text@v0.1.1-0.20190915032832-14c0d48ead0c: invalid pseudo-version: does not match version-control timestamp \(expected 20170915032832\)'
 cd ..
 go list -m golang.org/x/text
 stdout 'golang.org/x/text v0.1.1-0.20190915032832-14c0d48ead0c => golang.org/x/text v0.1.1-0.20170915032832-14c0d48ead0c'

src/cmd/internal/moddeps/moddeps_test.go

@@ -47,6 +47,7 @@ func findGorootModules(t *testing.T) []gorootModule {
 			// Use 'go list' to describe the module contained in this directory (but
 			// not its dependencies).
 			cmd := exec.Command(goBin, "list", "-json", "-m")
+			cmd.Env = append(os.Environ(), "GO111MODULE=on")
 			cmd.Dir = dir
 			cmd.Stderr = new(strings.Builder)
 			out, err := cmd.Output()
@@ -103,6 +104,7 @@ func TestAllDependenciesVendored(t *testing.T) {
 				// dependencies are vendored. If any imported package is missing,
 				// 'go list -deps' will fail when attempting to load it.
 				cmd := exec.Command(goBin, "list", "-mod=vendor", "-deps", "./...")
+				cmd.Env = append(os.Environ(), "GO111MODULE=on")
 				cmd.Dir = m.Dir
 				cmd.Stderr = new(strings.Builder)
 				_, err := cmd.Output()
@@ -115,7 +117,8 @@ func TestAllDependenciesVendored(t *testing.T) {
 
 			// There is no vendor directory, so the module must have no dependencies.
 			// Check that the list of active modules contains only the main module.
-			cmd := exec.Command(goBin, "list", "-m", "all")
+			cmd := exec.Command(goBin, "list", "-mod=mod", "-m", "all")
+			cmd.Env = append(os.Environ(), "GO111MODULE=on")
 			cmd.Dir = m.Dir
 			cmd.Stderr = new(strings.Builder)
 			out, err := cmd.Output()

src/cmd/internal/obj/ppc64/a.out.go

@@ -944,22 +944,16 @@ const (
 	ASTXVW4X
 	ASTXVH8X
 	ASTXVB16X
-	ALXS
 	ALXSDX
-	ASTXS
 	ASTXSDX
-	ALXSI
 	ALXSIWAX
 	ALXSIWZX
-	ASTXSI
 	ASTXSIWX
-	AMFVSR
 	AMFVSRD
 	AMFFPRD
 	AMFVRD
 	AMFVSRWZ
 	AMFVSRLD
-	AMTVSR
 	AMTVSRD
 	AMTFPRD
 	AMTVRD
@@ -968,7 +962,6 @@ const (
 	AMTVSRDD
 	AMTVSRWS
 	AXXLAND
-	AXXLANDQ
 	AXXLANDC
 	AXXLEQV
 	AXXLNAND
@@ -978,34 +971,27 @@ const (
 	AXXLORQ
 	AXXLXOR
 	AXXSEL
-	AXXMRG
 	AXXMRGHW
 	AXXMRGLW
 	AXXSPLT
 	AXXSPLTW
 	AXXPERM
 	AXXPERMDI
-	AXXSI
 	AXXSLDWI
-	AXSCV
 	AXSCVDPSP
 	AXSCVSPDP
 	AXSCVDPSPN
 	AXSCVSPDPN
-	AXVCV
 	AXVCVDPSP
 	AXVCVSPDP
-	AXSCVX
 	AXSCVDPSXDS
 	AXSCVDPSXWS
 	AXSCVDPUXDS
 	AXSCVDPUXWS
-	AXSCVXP
 	AXSCVSXDDP
 	AXSCVUXDDP
 	AXSCVSXDSP
 	AXSCVUXDSP
-	AXVCVX
 	AXVCVDPSXDS
 	AXVCVDPSXWS
 	AXVCVDPUXDS
@@ -1014,7 +1000,6 @@ const (
 	AXVCVSPSXWS
 	AXVCVSPUXDS
 	AXVCVSPUXWS
-	AXVCVXP
 	AXVCVSXDDP
 	AXVCVSXWDP
 	AXVCVUXDDP

src/cmd/internal/obj/ppc64/anames.go

@@ -532,22 +532,16 @@ var Anames = []string{
 	"STXVW4X",
 	"STXVH8X",
 	"STXVB16X",
-	"LXS",
 	"LXSDX",
-	"STXS",
 	"STXSDX",
-	"LXSI",
 	"LXSIWAX",
 	"LXSIWZX",
-	"STXSI",
 	"STXSIWX",
-	"MFVSR",
 	"MFVSRD",
 	"MFFPRD",
 	"MFVRD",
 	"MFVSRWZ",
 	"MFVSRLD",
-	"MTVSR",
 	"MTVSRD",
 	"MTFPRD",
 	"MTVRD",
@@ -556,7 +550,6 @@ var Anames = []string{
 	"MTVSRDD",
 	"MTVSRWS",
 	"XXLAND",
-	"XXLANDQ",
 	"XXLANDC",
 	"XXLEQV",
 	"XXLNAND",
@@ -566,34 +559,27 @@ var Anames = []string{
 	"XXLORQ",
 	"XXLXOR",
 	"XXSEL",
-	"XXMRG",
 	"XXMRGHW",
 	"XXMRGLW",
 	"XXSPLT",
 	"XXSPLTW",
 	"XXPERM",
 	"XXPERMDI",
-	"XXSI",
 	"XXSLDWI",
-	"XSCV",
 	"XSCVDPSP",
 	"XSCVSPDP",
 	"XSCVDPSPN",
 	"XSCVSPDPN",
-	"XVCV",
 	"XVCVDPSP",
 	"XVCVSPDP",
-	"XSCVX",
 	"XSCVDPSXDS",
 	"XSCVDPSXWS",
 	"XSCVDPUXDS",
 	"XSCVDPUXWS",
-	"XSCVXP",
 	"XSCVSXDDP",
 	"XSCVUXDDP",
 	"XSCVSXDSP",
 	"XSCVUXDSP",
-	"XVCVX",
 	"XVCVDPSXDS",
 	"XVCVDPSXWS",
 	"XVCVDPUXDS",
@@ -602,7 +588,6 @@ var Anames = []string{
 	"XVCVSPSXWS",
 	"XVCVSPUXDS",
 	"XVCVSPUXWS",
-	"XVCVXP",
 	"XVCVSXDDP",
 	"XVCVSXWDP",
 	"XVCVUXDDP",

src/cmd/internal/obj/ppc64/asm9.go

@@ -462,10 +462,10 @@ var optab = []Optab{
 	{AVSEL, C_VREG, C_VREG, C_VREG, C_VREG, 83, 4, 0}, /* vector select, va-form */
 
 	/* Vector splat */
-	{AVSPLT, C_SCON, C_VREG, C_NONE, C_VREG, 82, 4, 0}, /* vector splat, vx-form */
-	{AVSPLT, C_ADDCON, C_VREG, C_NONE, C_VREG, 82, 4, 0},
-	{AVSPLTI, C_SCON, C_NONE, C_NONE, C_VREG, 82, 4, 0}, /* vector splat immediate, vx-form */
-	{AVSPLTI, C_ADDCON, C_NONE, C_NONE, C_VREG, 82, 4, 0},
+	{AVSPLTB, C_SCON, C_VREG, C_NONE, C_VREG, 82, 4, 0}, /* vector splat, vx-form */
+	{AVSPLTB, C_ADDCON, C_VREG, C_NONE, C_VREG, 82, 4, 0},
+	{AVSPLTISB, C_SCON, C_NONE, C_NONE, C_VREG, 82, 4, 0}, /* vector splat immediate, vx-form */
+	{AVSPLTISB, C_ADDCON, C_NONE, C_NONE, C_VREG, 82, 4, 0},
 
 	/* Vector AES */
 	{AVCIPH, C_VREG, C_VREG, C_NONE, C_VREG, 82, 4, 0},  /* vector AES cipher, vx-form */
@@ -484,27 +484,27 @@ var optab = []Optab{
 	{ASTXV, C_VSREG, C_NONE, C_NONE, C_SOREG, 97, 4, 0},    /* vsx vector store, dq-form */
 
 	/* VSX scalar load */
-	{ALXS, C_SOREG, C_NONE, C_NONE, C_VSREG, 87, 4, 0}, /* vsx scalar load, xx1-form */
+	{ALXSDX, C_SOREG, C_NONE, C_NONE, C_VSREG, 87, 4, 0}, /* vsx scalar load, xx1-form */
 
 	/* VSX scalar store */
-	{ASTXS, C_VSREG, C_NONE, C_NONE, C_SOREG, 86, 4, 0}, /* vsx scalar store, xx1-form */
+	{ASTXSDX, C_VSREG, C_NONE, C_NONE, C_SOREG, 86, 4, 0}, /* vsx scalar store, xx1-form */
 
 	/* VSX scalar as integer load */
-	{ALXSI, C_SOREG, C_NONE, C_NONE, C_VSREG, 87, 4, 0}, /* vsx scalar as integer load, xx1-form */
+	{ALXSIWAX, C_SOREG, C_NONE, C_NONE, C_VSREG, 87, 4, 0}, /* vsx scalar as integer load, xx1-form */
 
 	/* VSX scalar store as integer */
-	{ASTXSI, C_VSREG, C_NONE, C_NONE, C_SOREG, 86, 4, 0}, /* vsx scalar as integer store, xx1-form */
+	{ASTXSIWX, C_VSREG, C_NONE, C_NONE, C_SOREG, 86, 4, 0}, /* vsx scalar as integer store, xx1-form */
 
 	/* VSX move from VSR */
-	{AMFVSR, C_VSREG, C_NONE, C_NONE, C_REG, 88, 4, 0}, /* vsx move from vsr, xx1-form */
-	{AMFVSR, C_FREG, C_NONE, C_NONE, C_REG, 88, 4, 0},
-	{AMFVSR, C_VREG, C_NONE, C_NONE, C_REG, 88, 4, 0},
+	{AMFVSRD, C_VSREG, C_NONE, C_NONE, C_REG, 88, 4, 0}, /* vsx move from vsr, xx1-form */
+	{AMFVSRD, C_FREG, C_NONE, C_NONE, C_REG, 88, 4, 0},
+	{AMFVSRD, C_VREG, C_NONE, C_NONE, C_REG, 88, 4, 0},
 
 	/* VSX move to VSR */
-	{AMTVSR, C_REG, C_NONE, C_NONE, C_VSREG, 88, 4, 0}, /* vsx move to vsr, xx1-form */
-	{AMTVSR, C_REG, C_REG, C_NONE, C_VSREG, 88, 4, 0},
-	{AMTVSR, C_REG, C_NONE, C_NONE, C_FREG, 88, 4, 0},
-	{AMTVSR, C_REG, C_NONE, C_NONE, C_VREG, 88, 4, 0},
+	{AMTVSRD, C_REG, C_NONE, C_NONE, C_VSREG, 88, 4, 0}, /* vsx move to vsr, xx1-form */
+	{AMTVSRD, C_REG, C_REG, C_NONE, C_VSREG, 88, 4, 0},
+	{AMTVSRD, C_REG, C_NONE, C_NONE, C_FREG, 88, 4, 0},
+	{AMTVSRD, C_REG, C_NONE, C_NONE, C_VREG, 88, 4, 0},
 
 	/* VSX logical */
 	{AXXLAND, C_VSREG, C_VSREG, C_NONE, C_VSREG, 90, 4, 0}, /* vsx and, xx3-form */
@@ -514,34 +514,34 @@ var optab = []Optab{
 	{AXXSEL, C_VSREG, C_VSREG, C_VSREG, C_VSREG, 91, 4, 0}, /* vsx select, xx4-form */
 
 	/* VSX merge */
-	{AXXMRG, C_VSREG, C_VSREG, C_NONE, C_VSREG, 90, 4, 0}, /* vsx merge, xx3-form */
+	{AXXMRGHW, C_VSREG, C_VSREG, C_NONE, C_VSREG, 90, 4, 0}, /* vsx merge, xx3-form */
 
 	/* VSX splat */
-	{AXXSPLT, C_VSREG, C_NONE, C_SCON, C_VSREG, 89, 4, 0}, /* vsx splat, xx2-form */
+	{AXXSPLTW, C_VSREG, C_NONE, C_SCON, C_VSREG, 89, 4, 0}, /* vsx splat, xx2-form */
 
 	/* VSX permute */
-	{AXXPERM, C_VSREG, C_VSREG, C_SCON, C_VSREG, 90, 4, 0}, /* vsx permute, xx3-form */
+	{AXXPERM, C_VSREG, C_VSREG, C_NONE, C_VSREG, 90, 4, 0}, /* vsx permute, xx3-form */
 
 	/* VSX shift */
-	{AXXSI, C_VSREG, C_VSREG, C_SCON, C_VSREG, 90, 4, 0}, /* vsx shift immediate, xx3-form */
+	{AXXSLDWI, C_VSREG, C_VSREG, C_SCON, C_VSREG, 90, 4, 0}, /* vsx shift immediate, xx3-form */
 
 	/* VSX scalar FP-FP conversion */
-	{AXSCV, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx scalar fp-fp conversion, xx2-form */
+	{AXSCVDPSP, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx scalar fp-fp conversion, xx2-form */
 
 	/* VSX vector FP-FP conversion */
-	{AXVCV, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx vector fp-fp conversion, xx2-form */
+	{AXVCVDPSP, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx vector fp-fp conversion, xx2-form */
 
 	/* VSX scalar FP-integer conversion */
-	{AXSCVX, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx scalar fp-integer conversion, xx2-form */
+	{AXSCVDPSXDS, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx scalar fp-integer conversion, xx2-form */
 
 	/* VSX scalar integer-FP conversion */
-	{AXSCVXP, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx scalar integer-fp conversion, xx2-form */
+	{AXSCVSXDDP, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx scalar integer-fp conversion, xx2-form */
 
 	/* VSX vector FP-integer conversion */
-	{AXVCVX, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx vector fp-integer conversion, xx2-form */
+	{AXVCVDPSXDS, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx vector fp-integer conversion, xx2-form */
 
 	/* VSX vector integer-FP conversion */
-	{AXVCVXP, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx vector integer-fp conversion, xx2-form */
+	{AXVCVSXDDP, C_VSREG, C_NONE, C_NONE, C_VSREG, 89, 4, 0}, /* vsx vector integer-fp conversion, xx2-form */
 
 	/* 64-bit special registers */
 	{AMOVD, C_REG, C_NONE, C_NONE, C_SPR, 66, 4, 0},
@@ -1519,13 +1519,11 @@ func buildop(ctxt *obj.Link) {
 		case AVSEL: /* vsel */
 			opset(AVSEL, r0)
 
-		case AVSPLT: /* vspltb, vsplth, vspltw */
-			opset(AVSPLTB, r0)
+		case AVSPLTB: /* vspltb, vsplth, vspltw */
 			opset(AVSPLTH, r0)
 			opset(AVSPLTW, r0)
 
-		case AVSPLTI: /* vspltisb, vspltish, vspltisw */
-			opset(AVSPLTISB, r0)
+		case AVSPLTISB: /* vspltisb, vspltish, vspltisw */
 			opset(AVSPLTISH, r0)
 			opset(AVSPLTISW, r0)
 
@@ -1561,28 +1559,25 @@ func buildop(ctxt *obj.Link) {
 		case ASTXV: /* stxv */
 			opset(ASTXV, r0)
 
-		case ALXS: /* lxsdx  */
+		case ALXSDX: /* lxsdx  */
 			opset(ALXSDX, r0)
 
-		case ASTXS: /* stxsdx */
+		case ASTXSDX: /* stxsdx */
 			opset(ASTXSDX, r0)
 
-		case ALXSI: /* lxsiwax, lxsiwzx  */
-			opset(ALXSIWAX, r0)
+		case ALXSIWAX: /* lxsiwax, lxsiwzx  */
 			opset(ALXSIWZX, r0)
 
-		case ASTXSI: /* stxsiwx */
+		case ASTXSIWX: /* stxsiwx */
 			opset(ASTXSIWX, r0)
 
-		case AMFVSR: /* mfvsrd, mfvsrwz (and extended mnemonics), mfvsrld */
-			opset(AMFVSRD, r0)
+		case AMFVSRD: /* mfvsrd, mfvsrwz (and extended mnemonics), mfvsrld */
 			opset(AMFFPRD, r0)
 			opset(AMFVRD, r0)
 			opset(AMFVSRWZ, r0)
 			opset(AMFVSRLD, r0)
 
-		case AMTVSR: /* mtvsrd, mtvsrwa, mtvsrwz (and extended mnemonics), mtvsrdd, mtvsrws */
-			opset(AMTVSRD, r0)
+		case AMTVSRD: /* mtvsrd, mtvsrwa, mtvsrwz (and extended mnemonics), mtvsrdd, mtvsrws */
 			opset(AMTFPRD, r0)
 			opset(AMTVRD, r0)
 			opset(AMTVSRWA, r0)
@@ -1591,7 +1586,6 @@ func buildop(ctxt *obj.Link) {
 			opset(AMTVSRWS, r0)
 
 		case AXXLAND: /* xxland, xxlandc, xxleqv, xxlnand */
-			opset(AXXLANDQ, r0)
 			opset(AXXLANDC, r0)
 			opset(AXXLEQV, r0)
 			opset(AXXLNAND, r0)
@@ -1605,42 +1599,38 @@ func buildop(ctxt *obj.Link) {
 		case AXXSEL: /* xxsel */
 			opset(AXXSEL, r0)
 
-		case AXXMRG: /* xxmrghw, xxmrglw */
-			opset(AXXMRGHW, r0)
+		case AXXMRGHW: /* xxmrghw, xxmrglw */
 			opset(AXXMRGLW, r0)
 
-		case AXXSPLT: /* xxspltw */
+		case AXXSPLTW: /* xxspltw */
 			opset(AXXSPLTW, r0)
 
 		case AXXPERM: /* xxpermdi */
-			opset(AXXPERMDI, r0)
+			opset(AXXPERM, r0)
 
-		case AXXSI: /* xxsldwi */
+		case AXXSLDWI: /* xxsldwi */
+			opset(AXXPERMDI, r0)
 			opset(AXXSLDWI, r0)
 
-		case AXSCV: /* xscvdpsp, xscvspdp, xscvdpspn, xscvspdpn */
-			opset(AXSCVDPSP, r0)
+		case AXSCVDPSP: /* xscvdpsp, xscvspdp, xscvdpspn, xscvspdpn */
 			opset(AXSCVSPDP, r0)
 			opset(AXSCVDPSPN, r0)
 			opset(AXSCVSPDPN, r0)
 
-		case AXVCV: /* xvcvdpsp, xvcvspdp */
-			opset(AXVCVDPSP, r0)
+		case AXVCVDPSP: /* xvcvdpsp, xvcvspdp */
 			opset(AXVCVSPDP, r0)
 
-		case AXSCVX: /* xscvdpsxds, xscvdpsxws, xscvdpuxds, xscvdpuxws */
-			opset(AXSCVDPSXDS, r0)
+		case AXSCVDPSXDS: /* xscvdpsxds, xscvdpsxws, xscvdpuxds, xscvdpuxws */
 			opset(AXSCVDPSXWS, r0)
 			opset(AXSCVDPUXDS, r0)
 			opset(AXSCVDPUXWS, r0)
 
-		case AXSCVXP: /* xscvsxddp, xscvuxddp, xscvsxdsp, xscvuxdsp */
-			opset(AXSCVSXDDP, r0)
+		case AXSCVSXDDP: /* xscvsxddp, xscvuxddp, xscvsxdsp, xscvuxdsp */
 			opset(AXSCVUXDDP, r0)
 			opset(AXSCVSXDSP, r0)
 			opset(AXSCVUXDSP, r0)
 
-		case AXVCVX: /* xvcvdpsxds, xvcvdpsxws, xvcvdpuxds, xvcvdpuxws, xvcvspsxds, xvcvspsxws, xvcvspuxds, xvcvspuxws */
+		case AXVCVDPSXDS: /* xvcvdpsxds, xvcvdpsxws, xvcvdpuxds, xvcvdpuxws, xvcvspsxds, xvcvspsxws, xvcvspuxds, xvcvspuxws */
 			opset(AXVCVDPSXDS, r0)
 			opset(AXVCVDPSXWS, r0)
 			opset(AXVCVDPUXDS, r0)
@@ -1650,8 +1640,7 @@ func buildop(ctxt *obj.Link) {
 			opset(AXVCVSPUXDS, r0)
 			opset(AXVCVSPUXWS, r0)
 
-		case AXVCVXP: /* xvcvsxddp, xvcvsxwdp, xvcvuxddp, xvcvuxwdp, xvcvsxdsp, xvcvsxwsp, xvcvuxdsp, xvcvuxwsp */
-			opset(AXVCVSXDDP, r0)
+		case AXVCVSXDDP: /* xvcvsxddp, xvcvsxwdp, xvcvuxddp, xvcvuxwdp, xvcvsxdsp, xvcvsxwsp, xvcvuxdsp, xvcvuxwsp */
 			opset(AXVCVSXWDP, r0)
 			opset(AXVCVUXDDP, r0)
 			opset(AXVCVUXWDP, r0)
@@ -4616,7 +4605,7 @@ func (c *ctxt9) oprrr(a obj.As) uint32 {
 	case AMTVSRWS:
 		return OPVXX1(31, 403, 0) /* mtvsrws - v3.00 */
 
-	case AXXLANDQ:
+	case AXXLAND:
 		return OPVXX3(60, 130, 0) /* xxland - v2.06 */
 	case AXXLANDC:
 		return OPVXX3(60, 138, 0) /* xxlandc - v2.06 */
@@ -4645,6 +4634,8 @@ func (c *ctxt9) oprrr(a obj.As) uint32 {
 	case AXXSPLTW:
 		return OPVXX2(60, 164, 0) /* xxspltw - v2.06 */
 
+	case AXXPERM:
+		return OPVXX3(60, 26, 0) /* xxperm - v2.06 */
 	case AXXPERMDI:
 		return OPVXX3(60, 10, 0) /* xxpermdi - v2.06 */
 

src/cmd/internal/objfile/disasm.go

@@ -175,6 +175,11 @@ func (fc *FileCache) Line(filename string, line int) ([]byte, error) {
 		fc.files.MoveToFront(e)
 	}
 
+	// because //line directives can be out-of-range. (#36683)
+	if line-1 >= len(cf.Lines) || line-1 < 0 {
+		return nil, nil
+	}
+
 	return cf.Lines[line-1], nil
 }
 

src/cmd/link/internal/ld/dwarf_test.go

@@ -1239,6 +1239,7 @@ func TestPackageNameAttr(t *testing.T) {
 	}
 
 	rdr := d.Reader()
+	runtimeUnitSeen := false
 	for {
 		e, err := rdr.Next()
 		if err != nil {
@@ -1254,11 +1255,25 @@ func TestPackageNameAttr(t *testing.T) {
 			continue
 		}
 
-		_, ok := e.Val(dwarfAttrGoPackageName).(string)
+		pn, ok := e.Val(dwarfAttrGoPackageName).(string)
 		if !ok {
 			name, _ := e.Val(dwarf.AttrName).(string)
 			t.Errorf("found compile unit without package name: %s", name)
+
 		}
+		if pn == "" {
+			name, _ := e.Val(dwarf.AttrName).(string)
+			t.Errorf("found compile unit with empty package name: %s", name)
+		} else {
+			if pn == "runtime" {
+				runtimeUnitSeen = true
+			}
+		}
+	}
+
+	// Something is wrong if there's no runtime compilation unit.
+	if !runtimeUnitSeen {
+		t.Errorf("no package name for runtime unit")
 	}
 }
 

src/cmd/link/internal/ld/pe.go

@@ -58,47 +58,15 @@ var (
 )
 
 const (
-	IMAGE_FILE_MACHINE_I386                        = 0x14c
-	IMAGE_FILE_MACHINE_AMD64                       = 0x8664
-	IMAGE_FILE_MACHINE_ARM                         = 0x1c0
-	IMAGE_FILE_MACHINE_ARMNT                       = 0x1c4
-	IMAGE_FILE_RELOCS_STRIPPED                     = 0x0001
-	IMAGE_FILE_EXECUTABLE_IMAGE                    = 0x0002
-	IMAGE_FILE_LINE_NUMS_STRIPPED                  = 0x0004
-	IMAGE_FILE_LARGE_ADDRESS_AWARE                 = 0x0020
-	IMAGE_FILE_32BIT_MACHINE                       = 0x0100
-	IMAGE_FILE_DEBUG_STRIPPED                      = 0x0200
-	IMAGE_SCN_CNT_CODE                             = 0x00000020
-	IMAGE_SCN_CNT_INITIALIZED_DATA                 = 0x00000040
-	IMAGE_SCN_CNT_UNINITIALIZED_DATA               = 0x00000080
-	IMAGE_SCN_MEM_EXECUTE                          = 0x20000000
-	IMAGE_SCN_MEM_READ                             = 0x40000000
-	IMAGE_SCN_MEM_WRITE                            = 0x80000000
-	IMAGE_SCN_MEM_DISCARDABLE                      = 0x2000000
-	IMAGE_SCN_LNK_NRELOC_OVFL                      = 0x1000000
-	IMAGE_SCN_ALIGN_32BYTES                        = 0x600000
-	IMAGE_DIRECTORY_ENTRY_EXPORT                   = 0
-	IMAGE_DIRECTORY_ENTRY_IMPORT                   = 1
-	IMAGE_DIRECTORY_ENTRY_RESOURCE                 = 2
-	IMAGE_DIRECTORY_ENTRY_EXCEPTION                = 3
-	IMAGE_DIRECTORY_ENTRY_SECURITY                 = 4
-	IMAGE_DIRECTORY_ENTRY_BASERELOC                = 5
-	IMAGE_DIRECTORY_ENTRY_DEBUG                    = 6
-	IMAGE_DIRECTORY_ENTRY_COPYRIGHT                = 7
-	IMAGE_DIRECTORY_ENTRY_ARCHITECTURE             = 7
-	IMAGE_DIRECTORY_ENTRY_GLOBALPTR                = 8
-	IMAGE_DIRECTORY_ENTRY_TLS                      = 9
-	IMAGE_DIRECTORY_ENTRY_LOAD_CONFIG              = 10
-	IMAGE_DIRECTORY_ENTRY_BOUND_IMPORT             = 11
-	IMAGE_DIRECTORY_ENTRY_IAT                      = 12
-	IMAGE_DIRECTORY_ENTRY_DELAY_IMPORT             = 13
-	IMAGE_DIRECTORY_ENTRY_COM_DESCRIPTOR           = 14
-	IMAGE_SUBSYSTEM_WINDOWS_GUI                    = 2
-	IMAGE_SUBSYSTEM_WINDOWS_CUI                    = 3
-	IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA       = 0x0020
-	IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE          = 0x0040
-	IMAGE_DLLCHARACTERISTICS_NX_COMPAT             = 0x0100
-	IMAGE_DLLCHARACTERISTICS_TERMINAL_SERVER_AWARE = 0x8000
+	IMAGE_SCN_CNT_CODE               = 0x00000020
+	IMAGE_SCN_CNT_INITIALIZED_DATA   = 0x00000040
+	IMAGE_SCN_CNT_UNINITIALIZED_DATA = 0x00000080
+	IMAGE_SCN_MEM_EXECUTE            = 0x20000000
+	IMAGE_SCN_MEM_READ               = 0x40000000
+	IMAGE_SCN_MEM_WRITE              = 0x80000000
+	IMAGE_SCN_MEM_DISCARDABLE        = 0x2000000
+	IMAGE_SCN_LNK_NRELOC_OVFL        = 0x1000000
+	IMAGE_SCN_ALIGN_32BYTES          = 0x600000
 )
 
 // TODO(crawshaw): add these constants to debug/pe.
@@ -762,11 +730,11 @@ func (f *peFile) writeFileHeader(ctxt *Link) {
 	default:
 		Exitf("unknown PE architecture: %v", ctxt.Arch.Family)
 	case sys.AMD64:
-		fh.Machine = IMAGE_FILE_MACHINE_AMD64
+		fh.Machine = pe.IMAGE_FILE_MACHINE_AMD64
 	case sys.I386:
-		fh.Machine = IMAGE_FILE_MACHINE_I386
+		fh.Machine = pe.IMAGE_FILE_MACHINE_I386
 	case sys.ARM:
-		fh.Machine = IMAGE_FILE_MACHINE_ARMNT
+		fh.Machine = pe.IMAGE_FILE_MACHINE_ARMNT
 	}
 
 	fh.NumberOfSections = uint16(len(f.sections))
@@ -776,24 +744,24 @@ func (f *peFile) writeFileHeader(ctxt *Link) {
 	fh.TimeDateStamp = 0
 
 	if ctxt.LinkMode == LinkExternal {
-		fh.Characteristics = IMAGE_FILE_LINE_NUMS_STRIPPED
+		fh.Characteristics = pe.IMAGE_FILE_LINE_NUMS_STRIPPED
 	} else {
-		fh.Characteristics = IMAGE_FILE_EXECUTABLE_IMAGE | IMAGE_FILE_DEBUG_STRIPPED
+		fh.Characteristics = pe.IMAGE_FILE_EXECUTABLE_IMAGE | pe.IMAGE_FILE_DEBUG_STRIPPED
 		switch ctxt.Arch.Family {
 		case sys.AMD64, sys.I386:
 			if ctxt.BuildMode != BuildModePIE {
-				fh.Characteristics |= IMAGE_FILE_RELOCS_STRIPPED
+				fh.Characteristics |= pe.IMAGE_FILE_RELOCS_STRIPPED
 			}
 		}
 	}
 	if pe64 != 0 {
 		var oh64 pe.OptionalHeader64
 		fh.SizeOfOptionalHeader = uint16(binary.Size(&oh64))
-		fh.Characteristics |= IMAGE_FILE_LARGE_ADDRESS_AWARE
+		fh.Characteristics |= pe.IMAGE_FILE_LARGE_ADDRESS_AWARE
 	} else {
 		var oh pe.OptionalHeader32
 		fh.SizeOfOptionalHeader = uint16(binary.Size(&oh))
-		fh.Characteristics |= IMAGE_FILE_32BIT_MACHINE
+		fh.Characteristics |= pe.IMAGE_FILE_32BIT_MACHINE
 	}
 
 	fh.PointerToSymbolTable = uint32(f.symtabOffset)
@@ -854,36 +822,36 @@ func (f *peFile) writeOptionalHeader(ctxt *Link) {
 	oh64.SizeOfHeaders = uint32(PEFILEHEADR)
 	oh.SizeOfHeaders = uint32(PEFILEHEADR)
 	if windowsgui {
-		oh64.Subsystem = IMAGE_SUBSYSTEM_WINDOWS_GUI
-		oh.Subsystem = IMAGE_SUBSYSTEM_WINDOWS_GUI
+		oh64.Subsystem = pe.IMAGE_SUBSYSTEM_WINDOWS_GUI
+		oh.Subsystem = pe.IMAGE_SUBSYSTEM_WINDOWS_GUI
 	} else {
-		oh64.Subsystem = IMAGE_SUBSYSTEM_WINDOWS_CUI
-		oh.Subsystem = IMAGE_SUBSYSTEM_WINDOWS_CUI
+		oh64.Subsystem = pe.IMAGE_SUBSYSTEM_WINDOWS_CUI
+		oh.Subsystem = pe.IMAGE_SUBSYSTEM_WINDOWS_CUI
 	}
 
 	// Mark as having awareness of terminal services, to avoid ancient compatibility hacks.
-	oh64.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_TERMINAL_SERVER_AWARE
-	oh.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_TERMINAL_SERVER_AWARE
+	oh64.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_TERMINAL_SERVER_AWARE
+	oh.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_TERMINAL_SERVER_AWARE
 
 	// Enable DEP
-	oh64.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_NX_COMPAT
-	oh.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_NX_COMPAT
+	oh64.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_NX_COMPAT
+	oh.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_NX_COMPAT
 
 	// The DLL can be relocated at load time.
 	switch ctxt.Arch.Family {
 	case sys.AMD64, sys.I386:
 		if ctxt.BuildMode == BuildModePIE {
-			oh64.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE
-			oh.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE
+			oh64.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE
+			oh.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE
 		}
 	case sys.ARM:
-		oh64.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE
-		oh.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE
+		oh64.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE
+		oh.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE
 	}
 
 	// Image can handle a high entropy 64-bit virtual address space.
 	if ctxt.BuildMode == BuildModePIE {
-		oh64.DllCharacteristics |= IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA
+		oh64.DllCharacteristics |= pe.IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA
 	}
 
 	// Disable stack growth as we don't want Windows to
@@ -1229,10 +1197,10 @@ func addimports(ctxt *Link, datsect *peSection) {
 	out.Write32(0)
 
 	// update data directory
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress = isect.virtualAddress
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].Size = isect.virtualSize
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress = uint32(dynamic.Value - PEBASE)
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].Size = uint32(dynamic.Size)
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress = isect.virtualAddress
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_IMPORT].Size = isect.virtualSize
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress = uint32(dynamic.Value - PEBASE)
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_IAT].Size = uint32(dynamic.Size)
 
 	out.SeekSet(endoff)
 }
@@ -1272,8 +1240,8 @@ func addexports(ctxt *Link) {
 	sect.characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ
 	sect.checkOffset(ctxt.Out.Offset())
 	va := int(sect.virtualAddress)
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress = uint32(va)
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].Size = sect.virtualSize
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress = uint32(va)
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_EXPORT].Size = sect.virtualSize
 
 	vaName := va + binary.Size(&e) + nexport*4
 	vaAddr := va + binary.Size(&e)
@@ -1481,8 +1449,8 @@ func addPEBaseReloc(ctxt *Link) {
 	rsect.checkOffset(startoff)
 	rsect.pad(ctxt.Out, uint32(size))
 
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress = rsect.virtualAddress
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size = rsect.virtualSize
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress = rsect.virtualAddress
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_BASERELOC].Size = rsect.virtualSize
 }
 
 func (ctxt *Link) dope() {
@@ -1528,9 +1496,9 @@ func addpersrc(ctxt *Link) {
 	h.pad(ctxt.Out, uint32(size))
 
 	// update data directory
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_RESOURCE].VirtualAddress = h.virtualAddress
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_RESOURCE].VirtualAddress = h.virtualAddress
 
-	pefile.dataDirectory[IMAGE_DIRECTORY_ENTRY_RESOURCE].Size = h.virtualSize
+	pefile.dataDirectory[pe.IMAGE_DIRECTORY_ENTRY_RESOURCE].Size = h.virtualSize
 }
 
 func Asmbpe(ctxt *Link) {

src/cmd/objdump/objdump_test.go

@@ -106,8 +106,11 @@ func testDisasm(t *testing.T, printCode bool, flags ...string) {
 	hello := filepath.Join(tmp, fmt.Sprintf("hello-%x.exe", hash))
 	args := []string{"build", "-o", hello}
 	args = append(args, flags...)
-	args = append(args, "testdata/fmthello.go")
-	out, err := exec.Command(testenv.GoToolPath(t), args...).CombinedOutput()
+	args = append(args, "fmthello.go")
+	cmd := exec.Command(testenv.GoToolPath(t), args...)
+	cmd.Dir = "testdata" // "Bad line" bug #36683 is sensitive to being run in the source directory
+	t.Logf("Running %v", cmd.Args)
+	out, err := cmd.CombinedOutput()
 	if err != nil {
 		t.Fatalf("go build fmthello.go: %v\n%s", err, out)
 	}
@@ -139,7 +142,11 @@ func testDisasm(t *testing.T, printCode bool, flags ...string) {
 		args = append([]string{"-S"}, args...)
 	}
 
-	out, err = exec.Command(exe, args...).CombinedOutput()
+	cmd = exec.Command(exe, args...)
+	cmd.Dir = "testdata" // "Bad line" bug #36683 is sensitive to being run in the source directory
+	out, err = cmd.CombinedOutput()
+	t.Logf("Running %v", cmd.Args)
+
 	if err != nil {
 		t.Fatalf("objdump fmthello.exe: %v\n%s", err, out)
 	}

src/cmd/objdump/testdata/fmthello.go

@@ -5,6 +5,8 @@ import "fmt"
 func main() {
 	Println("hello, world")
 	if flag {
+//line fmthello.go:999999
+		Println("bad line")
 		for {
 		}
 	}

src/cmd/vendor/github.com/google/pprof/internal/report/report.go

@@ -834,10 +834,19 @@ func printTraces(w io.Writer, rpt *Report) error {
 
 	_, locations := graph.CreateNodes(prof, &graph.Options{})
 	for _, sample := range prof.Sample {
-		var stack graph.Nodes
+		type stk struct {
+			*graph.NodeInfo
+			inline bool
+		}
+		var stack []stk
 		for _, loc := range sample.Location {
-			id := loc.ID
-			stack = append(stack, locations[id]...)
+			nodes := locations[loc.ID]
+			for i, n := range nodes {
+				// The inline flag may be inaccurate if 'show' or 'hide' filter is
+				// used. See https://github.com/google/pprof/issues/511.
+				inline := i != len(nodes)-1
+				stack = append(stack, stk{&n.Info, inline})
+			}
 		}
 
 		if len(stack) == 0 {
@@ -875,10 +884,15 @@ func printTraces(w io.Writer, rpt *Report) error {
 		if d != 0 {
 			v = v / d
 		}
-		fmt.Fprintf(w, "%10s   %s\n",
-			rpt.formatValue(v), stack[0].Info.PrintableName())
-		for _, s := range stack[1:] {
-			fmt.Fprintf(w, "%10s   %s\n", "", s.Info.PrintableName())
+		for i, s := range stack {
+			var vs, inline string
+			if i == 0 {
+				vs = rpt.formatValue(v)
+			}
+			if s.inline {
+				inline = " (inline)"
+			}
+			fmt.Fprintf(w, "%10s   %s%s\n", vs, s.PrintableName(), inline)
 		}
 	}
 	fmt.Fprintln(w, separator)

src/cmd/vendor/github.com/google/pprof/profile/proto.go

@@ -33,7 +33,10 @@
 
 package profile
 
-import "errors"
+import (
+	"errors"
+	"fmt"
+)
 
 type buffer struct {
 	field int // field tag
@@ -235,7 +238,7 @@ func decodeField(b *buffer, data []byte) ([]byte, error) {
 		b.u64 = uint64(le32(data[:4]))
 		data = data[4:]
 	default:
-		return nil, errors.New("unknown wire type: " + string(b.typ))
+		return nil, fmt.Errorf("unknown wire type: %d", b.typ)
 	}
 
 	return data, nil

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/errorsas/errorsas.go

@@ -51,7 +51,7 @@ func run(pass *analysis.Pass) (interface{}, error) {
 			return // not enough arguments, e.g. called with return values of another function
 		}
 		if fn.FullName() == "errors.As" && !pointerToInterfaceOrError(pass, call.Args[1]) {
-			pass.ReportRangef(call, "second argument to errors.As must be a pointer to an interface or a type implementing error")
+			pass.ReportRangef(call, "second argument to errors.As must be a non-nil pointer to either a type that implements error, or to any interface type")
 		}
 	})
 	return nil, nil

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/ifaceassert/ifaceassert.go

@@ -0,0 +1,101 @@
+// Copyright 2020 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.
+
+// Package ifaceassert defines an Analyzer that flags
+// impossible interface-interface type assertions.
+package ifaceassert
+
+import (
+	"go/ast"
+	"go/types"
+
+	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/analysis/passes/inspect"
+	"golang.org/x/tools/go/ast/inspector"
+)
+
+const Doc = `detect impossible interface-to-interface type assertions
+
+This checker flags type assertions v.(T) and corresponding type-switch cases
+in which the static type V of v is an interface that cannot possibly implement
+the target interface T. This occurs when V and T contain methods with the same
+name but different signatures. Example:
+
+	var v interface {
+		Read()
+	}
+	_ = v.(io.Reader)
+
+The Read method in v has a different signature than the Read method in
+io.Reader, so this assertion cannot succeed.
+`
+
+var Analyzer = &analysis.Analyzer{
+	Name:     "ifaceassert",
+	Doc:      Doc,
+	Requires: []*analysis.Analyzer{inspect.Analyzer},
+	Run:      run,
+}
+
+// assertableTo checks whether interface v can be asserted into t. It returns
+// nil on success, or the first conflicting method on failure.
+func assertableTo(v, t types.Type) *types.Func {
+	// ensure that v and t are interfaces
+	V, _ := v.Underlying().(*types.Interface)
+	T, _ := t.Underlying().(*types.Interface)
+	if V == nil || T == nil {
+		return nil
+	}
+	if f, wrongType := types.MissingMethod(V, T, false); wrongType {
+		return f
+	}
+	return nil
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
+	nodeFilter := []ast.Node{
+		(*ast.TypeAssertExpr)(nil),
+		(*ast.TypeSwitchStmt)(nil),
+	}
+	inspect.Preorder(nodeFilter, func(n ast.Node) {
+		var (
+			assert  *ast.TypeAssertExpr // v.(T) expression
+			targets []ast.Expr          // interfaces T in v.(T)
+		)
+		switch n := n.(type) {
+		case *ast.TypeAssertExpr:
+			// take care of v.(type) in *ast.TypeSwitchStmt
+			if n.Type == nil {
+				return
+			}
+			assert = n
+			targets = append(targets, n.Type)
+		case *ast.TypeSwitchStmt:
+			// retrieve type assertion from type switch's 'assign' field
+			switch t := n.Assign.(type) {
+			case *ast.ExprStmt:
+				assert = t.X.(*ast.TypeAssertExpr)
+			case *ast.AssignStmt:
+				assert = t.Rhs[0].(*ast.TypeAssertExpr)
+			}
+			// gather target types from case clauses
+			for _, c := range n.Body.List {
+				targets = append(targets, c.(*ast.CaseClause).List...)
+			}
+		}
+		V := pass.TypesInfo.TypeOf(assert.X)
+		for _, target := range targets {
+			T := pass.TypesInfo.TypeOf(target)
+			if f := assertableTo(V, T); f != nil {
+				pass.Reportf(
+					target.Pos(),
+					"impossible type assertion: no type can implement both %v and %v (conflicting types for %v method)",
+					V, T, f.Name(),
+				)
+			}
+		}
+	})
+	return nil, nil
+}

src/cmd/vendor/golang.org/x/tools/go/analysis/passes/stringintconv/string.go

@@ -0,0 +1,126 @@
+// Copyright 2020 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.
+
+// Package stringintconv defines an Analyzer that flags type conversions
+// from integers to strings.
+package stringintconv
+
+import (
+	"fmt"
+	"go/ast"
+	"go/types"
+
+	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/analysis/passes/inspect"
+	"golang.org/x/tools/go/ast/inspector"
+)
+
+const Doc = `check for string(int) conversions
+
+This checker flags conversions of the form string(x) where x is an integer
+(but not byte or rune) type. Such conversions are discouraged because they
+return the UTF-8 representation of the Unicode code point x, and not a decimal
+string representation of x as one might expect. Furthermore, if x denotes an
+invalid code point, the conversion cannot be statically rejected.
+
+For conversions that intend on using the code point, consider replacing them
+with string(rune(x)). Otherwise, strconv.Itoa and its equivalents return the
+string representation of the value in the desired base.
+`
+
+var Analyzer = &analysis.Analyzer{
+	Name:     "stringintconv",
+	Doc:      Doc,
+	Requires: []*analysis.Analyzer{inspect.Analyzer},
+	Run:      run,
+}
+
+func typeName(typ types.Type) string {
+	if v, _ := typ.(interface{ Name() string }); v != nil {
+		return v.Name()
+	}
+	if v, _ := typ.(interface{ Obj() *types.TypeName }); v != nil {
+		return v.Obj().Name()
+	}
+	return ""
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
+	nodeFilter := []ast.Node{
+		(*ast.CallExpr)(nil),
+	}
+	inspect.Preorder(nodeFilter, func(n ast.Node) {
+		call := n.(*ast.CallExpr)
+
+		// Retrieve target type name.
+		var tname *types.TypeName
+		switch fun := call.Fun.(type) {
+		case *ast.Ident:
+			tname, _ = pass.TypesInfo.Uses[fun].(*types.TypeName)
+		case *ast.SelectorExpr:
+			tname, _ = pass.TypesInfo.Uses[fun.Sel].(*types.TypeName)
+		}
+		if tname == nil {
+			return
+		}
+		target := tname.Name()
+
+		// Check that target type T in T(v) has an underlying type of string.
+		T, _ := tname.Type().Underlying().(*types.Basic)
+		if T == nil || T.Kind() != types.String {
+			return
+		}
+		if s := T.Name(); target != s {
+			target += " (" + s + ")"
+		}
+
+		// Check that type V of v has an underlying integral type that is not byte or rune.
+		if len(call.Args) != 1 {
+			return
+		}
+		v := call.Args[0]
+		vtyp := pass.TypesInfo.TypeOf(v)
+		V, _ := vtyp.Underlying().(*types.Basic)
+		if V == nil || V.Info()&types.IsInteger == 0 {
+			return
+		}
+		switch V.Kind() {
+		case types.Byte, types.Rune, types.UntypedRune:
+			return
+		}
+
+		// Retrieve source type name.
+		source := typeName(vtyp)
+		if source == "" {
+			return
+		}
+		if s := V.Name(); source != s {
+			source += " (" + s + ")"
+		}
+		diag := analysis.Diagnostic{
+			Pos:     n.Pos(),
+			Message: fmt.Sprintf("conversion from %s to %s yields a string of one rune", source, target),
+			SuggestedFixes: []analysis.SuggestedFix{
+				{
+					Message: "Did you mean to convert a rune to a string?",
+					TextEdits: []analysis.TextEdit{
+						{
+							Pos:     v.Pos(),
+							End:     v.Pos(),
+							NewText: []byte("rune("),
+						},
+						{
+							Pos:     v.End(),
+							End:     v.End(),
+							NewText: []byte(")"),
+						},
+					},
+				},
+			},
+		}
+		pass.Report(diag)
+	})
+	return nil, nil
+}

src/cmd/vendor/modules.txt

@@ -1,4 +1,4 @@
-# github.com/google/pprof v0.0.0-20200212024743-f11f1df84d12
+# github.com/google/pprof v0.0.0-20200229191704-1ebb73c60ed3
 ## explicit
 github.com/google/pprof/driver
 github.com/google/pprof/internal/binutils
@@ -43,7 +43,7 @@ golang.org/x/mod/zip
 ## explicit
 golang.org/x/sys/unix
 golang.org/x/sys/windows
-# golang.org/x/tools v0.0.0-20200219195521-7c4b6277d74d
+# golang.org/x/tools v0.0.0-20200309180859-aa4048aca1ca
 ## explicit
 golang.org/x/tools/go/analysis
 golang.org/x/tools/go/analysis/internal/analysisflags
@@ -59,6 +59,7 @@ golang.org/x/tools/go/analysis/passes/copylock
 golang.org/x/tools/go/analysis/passes/ctrlflow
 golang.org/x/tools/go/analysis/passes/errorsas
 golang.org/x/tools/go/analysis/passes/httpresponse
+golang.org/x/tools/go/analysis/passes/ifaceassert
 golang.org/x/tools/go/analysis/passes/inspect
 golang.org/x/tools/go/analysis/passes/internal/analysisutil
 golang.org/x/tools/go/analysis/passes/loopclosure
@@ -67,6 +68,7 @@ golang.org/x/tools/go/analysis/passes/nilfunc
 golang.org/x/tools/go/analysis/passes/printf
 golang.org/x/tools/go/analysis/passes/shift
 golang.org/x/tools/go/analysis/passes/stdmethods
+golang.org/x/tools/go/analysis/passes/stringintconv
 golang.org/x/tools/go/analysis/passes/structtag
 golang.org/x/tools/go/analysis/passes/tests
 golang.org/x/tools/go/analysis/passes/unmarshal
@@ -80,6 +82,5 @@ golang.org/x/tools/go/cfg
 golang.org/x/tools/go/types/objectpath
 golang.org/x/tools/go/types/typeutil
 # golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543
-## explicit
 golang.org/x/xerrors
 golang.org/x/xerrors/internal

src/cmd/vet/main.go

@@ -15,12 +15,14 @@ import (
 	"golang.org/x/tools/go/analysis/passes/copylock"
 	"golang.org/x/tools/go/analysis/passes/errorsas"
 	"golang.org/x/tools/go/analysis/passes/httpresponse"
+	"golang.org/x/tools/go/analysis/passes/ifaceassert"
 	"golang.org/x/tools/go/analysis/passes/loopclosure"
 	"golang.org/x/tools/go/analysis/passes/lostcancel"
 	"golang.org/x/tools/go/analysis/passes/nilfunc"
 	"golang.org/x/tools/go/analysis/passes/printf"
 	"golang.org/x/tools/go/analysis/passes/shift"
 	"golang.org/x/tools/go/analysis/passes/stdmethods"
+	"golang.org/x/tools/go/analysis/passes/stringintconv"
 	"golang.org/x/tools/go/analysis/passes/structtag"
 	"golang.org/x/tools/go/analysis/passes/tests"
 	"golang.org/x/tools/go/analysis/passes/unmarshal"
@@ -43,12 +45,14 @@ func main() {
 		copylock.Analyzer,
 		errorsas.Analyzer,
 		httpresponse.Analyzer,
+		ifaceassert.Analyzer,
 		loopclosure.Analyzer,
 		lostcancel.Analyzer,
 		nilfunc.Analyzer,
 		printf.Analyzer,
 		shift.Analyzer,
 		stdmethods.Analyzer,
+		stringintconv.Analyzer,
 		structtag.Analyzer,
 		tests.Analyzer,
 		unmarshal.Analyzer,

src/crypto/tls/auth.go

@@ -106,7 +106,7 @@ func typeAndHashFromSignatureScheme(signatureAlgorithm SignatureScheme) (sigType
 	case Ed25519:
 		sigType = signatureEd25519
 	default:
-		return 0, 0, fmt.Errorf("unsupported signature algorithm: %#04x", signatureAlgorithm)
+		return 0, 0, fmt.Errorf("unsupported signature algorithm: %v", signatureAlgorithm)
 	}
 	switch signatureAlgorithm {
 	case PKCS1WithSHA1, ECDSAWithSHA1:
@@ -120,7 +120,7 @@ func typeAndHashFromSignatureScheme(signatureAlgorithm SignatureScheme) (sigType
 	case Ed25519:
 		hash = directSigning
 	default:
-		return 0, 0, fmt.Errorf("unsupported signature algorithm: %#04x", signatureAlgorithm)
+		return 0, 0, fmt.Errorf("unsupported signature algorithm: %v", signatureAlgorithm)
 	}
 	return sigType, hash, nil
 }

src/crypto/tls/auth_test.go

@@ -62,7 +62,7 @@ func TestSignatureSelection(t *testing.T) {
 			t.Errorf("test[%d]: unexpected selectSignatureScheme error: %v", testNo, err)
 		}
 		if test.expectedSigAlg != sigAlg {
-			t.Errorf("test[%d]: expected signature scheme %#x, got %#x", testNo, test.expectedSigAlg, sigAlg)
+			t.Errorf("test[%d]: expected signature scheme %v, got %v", testNo, test.expectedSigAlg, sigAlg)
 		}
 		sigType, hashFunc, err := typeAndHashFromSignatureScheme(sigAlg)
 		if err != nil {
@@ -115,7 +115,7 @@ func TestSignatureSelection(t *testing.T) {
 	for testNo, test := range badTests {
 		sigAlg, err := selectSignatureScheme(test.tlsVersion, test.cert, test.peerSigAlgs)
 		if err == nil {
-			t.Errorf("test[%d]: unexpected success, got %#x", testNo, sigAlg)
+			t.Errorf("test[%d]: unexpected success, got %v", testNo, sigAlg)
 		}
 	}
 }
@@ -129,7 +129,7 @@ func TestLegacyTypeAndHash(t *testing.T) {
 		t.Errorf("RSA: expected signature type %#x, got %#x", expectedSigType, sigType)
 	}
 	if expectedHashFunc := crypto.MD5SHA1; expectedHashFunc != hashFunc {
-		t.Errorf("RSA: expected hash %#x, got %#x", expectedHashFunc, sigType)
+		t.Errorf("RSA: expected hash %#x, got %#x", expectedHashFunc, hashFunc)
 	}
 
 	sigType, hashFunc, err = legacyTypeAndHashFromPublicKey(testECDSAPrivateKey.Public())
@@ -140,7 +140,7 @@ func TestLegacyTypeAndHash(t *testing.T) {
 		t.Errorf("ECDSA: expected signature type %#x, got %#x", expectedSigType, sigType)
 	}
 	if expectedHashFunc := crypto.SHA1; expectedHashFunc != hashFunc {
-		t.Errorf("ECDSA: expected hash %#x, got %#x", expectedHashFunc, sigType)
+		t.Errorf("ECDSA: expected hash %#x, got %#x", expectedHashFunc, hashFunc)
 	}
 
 	// Ed25519 is not supported by TLS 1.0 and 1.1.
@@ -156,13 +156,13 @@ func TestSupportedSignatureAlgorithms(t *testing.T) {
 	for _, sigAlg := range supportedSignatureAlgorithms {
 		sigType, hash, err := typeAndHashFromSignatureScheme(sigAlg)
 		if err != nil {
-			t.Errorf("%#04x: unexpected error: %v", sigAlg, err)
+			t.Errorf("%v: unexpected error: %v", sigAlg, err)
 		}
 		if sigType == 0 {
-			t.Errorf("%#04x: missing signature type", sigAlg)
+			t.Errorf("%v: missing signature type", sigAlg)
 		}
 		if hash == 0 && sigAlg != Ed25519 {
-			t.Errorf("%#04x: missing hash", sigAlg)
+			t.Errorf("%v: missing hash", sigAlg)
 		}
 	}
 }

src/crypto/tls/common.go

@@ -299,6 +299,8 @@ type ClientSessionCache interface {
 	Put(sessionKey string, cs *ClientSessionState)
 }
 
+//go:generate stringer -type=SignatureScheme,CurveID,ClientAuthType -output=common_string.go
+
 // SignatureScheme identifies a signature algorithm supported by TLS. See
 // RFC 8446, Section 4.2.3.
 type SignatureScheme uint16

src/crypto/tls/common_string.go

@@ -0,0 +1,116 @@
+// Code generated by "stringer -type=SignatureScheme,CurveID,ClientAuthType -output=common_string.go"; DO NOT EDIT.
+
+package tls
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[PKCS1WithSHA256-1025]
+	_ = x[PKCS1WithSHA384-1281]
+	_ = x[PKCS1WithSHA512-1537]
+	_ = x[PSSWithSHA256-2052]
+	_ = x[PSSWithSHA384-2053]
+	_ = x[PSSWithSHA512-2054]
+	_ = x[ECDSAWithP256AndSHA256-1027]
+	_ = x[ECDSAWithP384AndSHA384-1283]
+	_ = x[ECDSAWithP521AndSHA512-1539]
+	_ = x[Ed25519-2055]
+	_ = x[PKCS1WithSHA1-513]
+	_ = x[ECDSAWithSHA1-515]
+}
+
+const (
+	_SignatureScheme_name_0 = "PKCS1WithSHA1"
+	_SignatureScheme_name_1 = "ECDSAWithSHA1"
+	_SignatureScheme_name_2 = "PKCS1WithSHA256"
+	_SignatureScheme_name_3 = "ECDSAWithP256AndSHA256"
+	_SignatureScheme_name_4 = "PKCS1WithSHA384"
+	_SignatureScheme_name_5 = "ECDSAWithP384AndSHA384"
+	_SignatureScheme_name_6 = "PKCS1WithSHA512"
+	_SignatureScheme_name_7 = "ECDSAWithP521AndSHA512"
+	_SignatureScheme_name_8 = "PSSWithSHA256PSSWithSHA384PSSWithSHA512Ed25519"
+)
+
+var (
+	_SignatureScheme_index_8 = [...]uint8{0, 13, 26, 39, 46}
+)
+
+func (i SignatureScheme) String() string {
+	switch {
+	case i == 513:
+		return _SignatureScheme_name_0
+	case i == 515:
+		return _SignatureScheme_name_1
+	case i == 1025:
+		return _SignatureScheme_name_2
+	case i == 1027:
+		return _SignatureScheme_name_3
+	case i == 1281:
+		return _SignatureScheme_name_4
+	case i == 1283:
+		return _SignatureScheme_name_5
+	case i == 1537:
+		return _SignatureScheme_name_6
+	case i == 1539:
+		return _SignatureScheme_name_7
+	case 2052 <= i && i <= 2055:
+		i -= 2052
+		return _SignatureScheme_name_8[_SignatureScheme_index_8[i]:_SignatureScheme_index_8[i+1]]
+	default:
+		return "SignatureScheme(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+}
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[CurveP256-23]
+	_ = x[CurveP384-24]
+	_ = x[CurveP521-25]
+	_ = x[X25519-29]
+}
+
+const (
+	_CurveID_name_0 = "CurveP256CurveP384CurveP521"
+	_CurveID_name_1 = "X25519"
+)
+
+var (
+	_CurveID_index_0 = [...]uint8{0, 9, 18, 27}
+)
+
+func (i CurveID) String() string {
+	switch {
+	case 23 <= i && i <= 25:
+		i -= 23
+		return _CurveID_name_0[_CurveID_index_0[i]:_CurveID_index_0[i+1]]
+	case i == 29:
+		return _CurveID_name_1
+	default:
+		return "CurveID(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+}
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[NoClientCert-0]
+	_ = x[RequestClientCert-1]
+	_ = x[RequireAnyClientCert-2]
+	_ = x[VerifyClientCertIfGiven-3]
+	_ = x[RequireAndVerifyClientCert-4]
+}
+
+const _ClientAuthType_name = "NoClientCertRequestClientCertRequireAnyClientCertVerifyClientCertIfGivenRequireAndVerifyClientCert"
+
+var _ClientAuthType_index = [...]uint8{0, 12, 29, 49, 72, 98}
+
+func (i ClientAuthType) String() string {
+	if i < 0 || i >= ClientAuthType(len(_ClientAuthType_index)-1) {
+		return "ClientAuthType(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _ClientAuthType_name[_ClientAuthType_index[i]:_ClientAuthType_index[i+1]]
+}

src/debug/pe/file_test.go

@@ -621,16 +621,14 @@ func TestBuildingWindowsGUI(t *testing.T) {
 	}
 	defer f.Close()
 
-	const _IMAGE_SUBSYSTEM_WINDOWS_GUI = 2
-
 	switch oh := f.OptionalHeader.(type) {
 	case *OptionalHeader32:
-		if oh.Subsystem != _IMAGE_SUBSYSTEM_WINDOWS_GUI {
-			t.Errorf("unexpected Subsystem value: have %d, but want %d", oh.Subsystem, _IMAGE_SUBSYSTEM_WINDOWS_GUI)
+		if oh.Subsystem != IMAGE_SUBSYSTEM_WINDOWS_GUI {
+			t.Errorf("unexpected Subsystem value: have %d, but want %d", oh.Subsystem, IMAGE_SUBSYSTEM_WINDOWS_GUI)
 		}
 	case *OptionalHeader64:
-		if oh.Subsystem != _IMAGE_SUBSYSTEM_WINDOWS_GUI {
-			t.Errorf("unexpected Subsystem value: have %d, but want %d", oh.Subsystem, _IMAGE_SUBSYSTEM_WINDOWS_GUI)
+		if oh.Subsystem != IMAGE_SUBSYSTEM_WINDOWS_GUI {
+			t.Errorf("unexpected Subsystem value: have %d, but want %d", oh.Subsystem, IMAGE_SUBSYSTEM_WINDOWS_GUI)
 		}
 	default:
 		t.Fatalf("unexpected OptionalHeader type: have %T, but want *pe.OptionalHeader32 or *pe.OptionalHeader64", oh)

src/debug/pe/pe.go

@@ -129,3 +129,56 @@ const (
 	IMAGE_DIRECTORY_ENTRY_DELAY_IMPORT   = 13
 	IMAGE_DIRECTORY_ENTRY_COM_DESCRIPTOR = 14
 )
+
+// Values of IMAGE_FILE_HEADER.Characteristics. These can be combined together.
+const (
+	IMAGE_FILE_RELOCS_STRIPPED         = 0x0001
+	IMAGE_FILE_EXECUTABLE_IMAGE        = 0x0002
+	IMAGE_FILE_LINE_NUMS_STRIPPED      = 0x0004
+	IMAGE_FILE_LOCAL_SYMS_STRIPPED     = 0x0008
+	IMAGE_FILE_AGGRESIVE_WS_TRIM       = 0x0010
+	IMAGE_FILE_LARGE_ADDRESS_AWARE     = 0x0020
+	IMAGE_FILE_BYTES_REVERSED_LO       = 0x0080
+	IMAGE_FILE_32BIT_MACHINE           = 0x0100
+	IMAGE_FILE_DEBUG_STRIPPED          = 0x0200
+	IMAGE_FILE_REMOVABLE_RUN_FROM_SWAP = 0x0400
+	IMAGE_FILE_NET_RUN_FROM_SWAP       = 0x0800
+	IMAGE_FILE_SYSTEM                  = 0x1000
+	IMAGE_FILE_DLL                     = 0x2000
+	IMAGE_FILE_UP_SYSTEM_ONLY          = 0x4000
+	IMAGE_FILE_BYTES_REVERSED_HI       = 0x8000
+)
+
+// OptionalHeader64.Subsystem and OptionalHeader32.Subsystem values.
+const (
+	IMAGE_SUBSYSTEM_UNKNOWN                  = 0
+	IMAGE_SUBSYSTEM_NATIVE                   = 1
+	IMAGE_SUBSYSTEM_WINDOWS_GUI              = 2
+	IMAGE_SUBSYSTEM_WINDOWS_CUI              = 3
+	IMAGE_SUBSYSTEM_OS2_CUI                  = 5
+	IMAGE_SUBSYSTEM_POSIX_CUI                = 7
+	IMAGE_SUBSYSTEM_NATIVE_WINDOWS           = 8
+	IMAGE_SUBSYSTEM_WINDOWS_CE_GUI           = 9
+	IMAGE_SUBSYSTEM_EFI_APPLICATION          = 10
+	IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER  = 11
+	IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER       = 12
+	IMAGE_SUBSYSTEM_EFI_ROM                  = 13
+	IMAGE_SUBSYSTEM_XBOX                     = 14
+	IMAGE_SUBSYSTEM_WINDOWS_BOOT_APPLICATION = 16
+)
+
+// OptionalHeader64.DllCharacteristics and OptionalHeader32.DllCharacteristics
+// values. These can be combined together.
+const (
+	IMAGE_DLLCHARACTERISTICS_HIGH_ENTROPY_VA       = 0x0020
+	IMAGE_DLLCHARACTERISTICS_DYNAMIC_BASE          = 0x0040
+	IMAGE_DLLCHARACTERISTICS_FORCE_INTEGRITY       = 0x0080
+	IMAGE_DLLCHARACTERISTICS_NX_COMPAT             = 0x0100
+	IMAGE_DLLCHARACTERISTICS_NO_ISOLATION          = 0x0200
+	IMAGE_DLLCHARACTERISTICS_NO_SEH                = 0x0400
+	IMAGE_DLLCHARACTERISTICS_NO_BIND               = 0x0800
+	IMAGE_DLLCHARACTERISTICS_APPCONTAINER          = 0x1000
+	IMAGE_DLLCHARACTERISTICS_WDM_DRIVER            = 0x2000
+	IMAGE_DLLCHARACTERISTICS_GUARD_CF              = 0x4000
+	IMAGE_DLLCHARACTERISTICS_TERMINAL_SERVER_AWARE = 0x8000
+)

src/errors/wrap.go

@@ -70,7 +70,7 @@ func Is(err, target error) bool {
 // setting target.
 //
 // An error type might provide an As method so it can be treated as if it were a
-// a different error type.
+// different error type.
 //
 // As panics if target is not a non-nil pointer to either a type that implements
 // error, or to any interface type.

src/go.mod

@@ -4,7 +4,7 @@ go 1.14
 
 require (
 	golang.org/x/crypto v0.0.0-20200214034016-1d94cc7ab1c6
-	golang.org/x/net v0.0.0-20200219183655-46282727080f
+	golang.org/x/net v0.0.0-20200301022130-244492dfa37a
 	golang.org/x/sys v0.0.0-20200219091948-cb0a6d8edb6c // indirect
 	golang.org/x/text v0.3.3-0.20191031172631-4b67af870c6f // indirect
 )

src/go.sum

@@ -2,8 +2,8 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACk
 golang.org/x/crypto v0.0.0-20200214034016-1d94cc7ab1c6 h1:Sy5bstxEqwwbYs6n0/pBuxKENqOeZUgD45Gp3Q3pqLg=
 golang.org/x/crypto v0.0.0-20200214034016-1d94cc7ab1c6/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/net v0.0.0-20200219183655-46282727080f h1:dB42wwhNuwPvh8f+5zZWNcU+F2Xs/B9wXXwvUCOH7r8=
-golang.org/x/net v0.0.0-20200219183655-46282727080f/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20200301022130-244492dfa37a h1:GuSPYbZzB5/dcLNCwLQLsg3obCJtX9IJhpXkvY7kzk0=
+golang.org/x/net v0.0.0-20200301022130-244492dfa37a/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200219091948-cb0a6d8edb6c h1:jceGD5YNJGgGMkJz79agzOln1K9TaZUjv5ird16qniQ=

src/internal/bytealg/bytealg.go

@@ -20,6 +20,7 @@ const (
 )
 
 // MaxLen is the maximum length of the string to be searched for (argument b) in Index.
+// If MaxLen is not 0, make sure MaxLen >= 4.
 var MaxLen int
 
 // FIXME: the logic of HashStrBytes, HashStrRevBytes, IndexRabinKarpBytes and HashStr, HashStrRev,

src/internal/bytealg/index_generic.go

@@ -16,8 +16,42 @@ func Index(a, b []byte) int {
 
 // IndexString returns the index of the first instance of b in a, or -1 if b is not present in a.
 // Requires 2 <= len(b) <= MaxLen.
-func IndexString(a, b string) int {
-	panic("unimplemented")
+func IndexString(s, substr string) int {
+	// This is a partial copy of strings.Index, here because bytes.IndexAny and bytes.LastIndexAny
+	// call bytealg.IndexString. Some platforms have an optimized assembly version of this function.
+	// This implementation is used for those that do not. Although the pure Go implementation here
+	// works for the case of len(b) > MaxLen, we do not require that its assembly implementation also
+	// supports the case of len(b) > MaxLen. And we do not guarantee that this function supports the
+	// case of len(b) > MaxLen.
+	n := len(substr)
+	c0 := substr[0]
+	c1 := substr[1]
+	i := 0
+	t := len(s) - n + 1
+	fails := 0
+	for i < t {
+		if s[i] != c0 {
+			o := IndexByteString(s[i:t], c0)
+			if o < 0 {
+				return -1
+			}
+			i += o
+		}
+		if s[i+1] == c1 && s[i:i+n] == substr {
+			return i
+		}
+		i++
+		fails++
+		if fails >= 4+i>>4 && i < t {
+			// See comment in src/bytes/bytes.go.
+			j := IndexRabinKarp(s[i:], substr)
+			if j < 0 {
+				return -1
+			}
+			return i + j
+		}
+	}
+	return -1
 }
 
 // Cutover reports the number of failures of IndexByte we should tolerate

src/internal/xcoff/file.go

@@ -412,10 +412,10 @@ func NewFile(r io.ReaderAt) (*File, error) {
 				sect.Relocs[i].Type = rel.Rtype
 				sect.Relocs[i].Length = rel.Rsize&0x3F + 1
 
-				if rel.Rsize&0x80 == 1 {
+				if rel.Rsize&0x80 != 0 {
 					sect.Relocs[i].Signed = true
 				}
-				if rel.Rsize&0x40 == 1 {
+				if rel.Rsize&0x40 != 0 {
 					sect.Relocs[i].InstructionFixed = true
 				}
 
@@ -428,10 +428,10 @@ func NewFile(r io.ReaderAt) (*File, error) {
 				sect.Relocs[i].Symbol = idxToSym[int(rel.Rsymndx)]
 				sect.Relocs[i].Type = rel.Rtype
 				sect.Relocs[i].Length = rel.Rsize&0x3F + 1
-				if rel.Rsize&0x80 == 1 {
+				if rel.Rsize&0x80 != 0 {
 					sect.Relocs[i].Signed = true
 				}
-				if rel.Rsize&0x40 == 1 {
+				if rel.Rsize&0x40 != 0 {
 					sect.Relocs[i].InstructionFixed = true
 				}
 			}

src/io/io.go

@@ -236,6 +236,10 @@ type WriterAt interface {
 // ReadByte reads and returns the next byte from the input or
 // any error encountered. If ReadByte returns an error, no input
 // byte was consumed, and the returned byte value is undefined.
+//
+// ReadByte provides an efficient interface for byte-at-time
+// processing. A Reader that does not implement  ByteReader
+// can be wrapped using bufio.NewReader to add this method.
 type ByteReader interface {
 	ReadByte() (byte, error)
 }

src/mime/type.go

@@ -65,6 +65,7 @@ var builtinTypesLower = map[string]string{
 	".jpeg": "image/jpeg",
 	".jpg":  "image/jpeg",
 	".js":   "text/javascript; charset=utf-8",
+	".json": "application/json",
 	".mjs":  "text/javascript; charset=utf-8",
 	".pdf":  "application/pdf",
 	".png":  "image/png",

src/net/dial_test.go

@@ -441,6 +441,14 @@ func TestDialParallelSpuriousConnection(t *testing.T) {
 		t.Skip("both IPv4 and IPv6 are required")
 	}
 
+	var readDeadline time.Time
+	if td, ok := t.Deadline(); ok {
+		const arbitraryCleanupMargin = 1 * time.Second
+		readDeadline = td.Add(-arbitraryCleanupMargin)
+	} else {
+		readDeadline = time.Now().Add(5 * time.Second)
+	}
+
 	var wg sync.WaitGroup
 	wg.Add(2)
 	handler := func(dss *dualStackServer, ln Listener) {
@@ -450,7 +458,7 @@ func TestDialParallelSpuriousConnection(t *testing.T) {
 			t.Fatal(err)
 		}
 		// The client should close itself, without sending data.
-		c.SetReadDeadline(time.Now().Add(1 * time.Second))
+		c.SetReadDeadline(readDeadline)
 		var b [1]byte
 		if _, err := c.Read(b[:]); err != io.EOF {
 			t.Errorf("got %v; want %v", err, io.EOF)

src/net/http/cgi/child.go

@@ -89,8 +89,6 @@ func RequestFromMap(params map[string]string) (*http.Request, error) {
 		r.Header.Add(strings.ReplaceAll(k[5:], "_", "-"), v)
 	}
 
-	// TODO: cookies.  parsing them isn't exported, though.
-
 	uriStr := params["REQUEST_URI"]
 	if uriStr == "" {
 		// Fallback to SCRIPT_NAME, PATH_INFO and QUERY_STRING.

src/net/http/serve_test.go

@@ -4135,10 +4135,19 @@ func TestServerConnState(t *testing.T) {
 
 		doRequests()
 
-		timer := time.NewTimer(5 * time.Second)
+		stateDelay := 5 * time.Second
+		if deadline, ok := t.Deadline(); ok {
+			// Allow an arbitrarily long delay.
+			// This test was observed to be flaky on the darwin-arm64-corellium builder,
+			// so we're increasing the deadline to see if it starts passing.
+			// See https://golang.org/issue/37322.
+			const arbitraryCleanupMargin = 1 * time.Second
+			stateDelay = time.Until(deadline) - arbitraryCleanupMargin
+		}
+		timer := time.NewTimer(stateDelay)
 		select {
 		case <-timer.C:
-			t.Errorf("Timed out waiting for connection to change state.")
+			t.Errorf("Timed out after %v waiting for connection to change state.", stateDelay)
 		case <-complete:
 			timer.Stop()
 		}

src/runtime/alg.go

@@ -158,6 +158,8 @@ func nilinterhash(p unsafe.Pointer, h uintptr) uintptr {
 // is slower but more general and is used for hashing interface types
 // (called from interhash or nilinterhash, above) or for hashing in
 // maps generated by reflect.MapOf (reflect_typehash, below).
+// Note: this function must match the compiler generated
+// functions exactly. See issue 37716.
 func typehash(t *_type, p unsafe.Pointer, h uintptr) uintptr {
 	if t.tflag&tflagRegularMemory != 0 {
 		// Handle ptr sizes specially, see issue 37086.
@@ -195,12 +197,28 @@ func typehash(t *_type, p unsafe.Pointer, h uintptr) uintptr {
 		return h
 	case kindStruct:
 		s := (*structtype)(unsafe.Pointer(t))
+		memStart := uintptr(0)
+		memEnd := uintptr(0)
 		for _, f := range s.fields {
-			// TODO: maybe we could hash several contiguous fields all at once.
+			if memEnd > memStart && (f.name.isBlank() || f.offset() != memEnd || f.typ.tflag&tflagRegularMemory == 0) {
+				// flush any pending regular memory hashing
+				h = memhash(add(p, memStart), h, memEnd-memStart)
+				memStart = memEnd
+			}
 			if f.name.isBlank() {
 				continue
 			}
-			h = typehash(f.typ, add(p, f.offset()), h)
+			if f.typ.tflag&tflagRegularMemory == 0 {
+				h = typehash(f.typ, add(p, f.offset()), h)
+				continue
+			}
+			if memStart == memEnd {
+				memStart = f.offset()
+			}
+			memEnd = f.offset() + f.typ.size
+		}
+		if memEnd > memStart {
+			h = memhash(add(p, memStart), h, memEnd-memStart)
 		}
 		return h
 	default:

src/runtime/checkptr.go

@@ -10,18 +10,18 @@ func checkptrAlignment(p unsafe.Pointer, elem *_type, n uintptr) {
 	// Check that (*[n]elem)(p) is appropriately aligned.
 	// TODO(mdempsky): What about fieldAlign?
 	if uintptr(p)&(uintptr(elem.align)-1) != 0 {
-		throw("checkptr: unsafe pointer conversion")
+		throw("checkptr: misaligned pointer conversion")
 	}
 
 	// Check that (*[n]elem)(p) doesn't straddle multiple heap objects.
 	if size := n * elem.size; size > 1 && checkptrBase(p) != checkptrBase(add(p, size-1)) {
-		throw("checkptr: unsafe pointer conversion")
+		throw("checkptr: converted pointer straddles multiple allocations")
 	}
 }
 
 func checkptrArithmetic(p unsafe.Pointer, originals []unsafe.Pointer) {
 	if 0 < uintptr(p) && uintptr(p) < minLegalPointer {
-		throw("checkptr: unsafe pointer arithmetic")
+		throw("checkptr: pointer arithmetic computed bad pointer value")
 	}
 
 	// Check that if the computed pointer p points into a heap
@@ -38,7 +38,7 @@ func checkptrArithmetic(p unsafe.Pointer, originals []unsafe.Pointer) {
 		}
 	}
 
-	throw("checkptr: unsafe pointer arithmetic")
+	throw("checkptr: pointer arithmetic result points to invalid allocation")
 }
 
 // checkptrBase returns the base address for the allocation containing

src/runtime/checkptr_test.go

@@ -24,10 +24,10 @@ func TestCheckPtr(t *testing.T) {
 		cmd  string
 		want string
 	}{
-		{"CheckPtrAlignment", "fatal error: checkptr: unsafe pointer conversion\n"},
-		{"CheckPtrArithmetic", "fatal error: checkptr: unsafe pointer arithmetic\n"},
-		{"CheckPtrSize", "fatal error: checkptr: unsafe pointer conversion\n"},
-		{"CheckPtrSmall", "fatal error: checkptr: unsafe pointer arithmetic\n"},
+		{"CheckPtrAlignment", "fatal error: checkptr: misaligned pointer conversion\n"},
+		{"CheckPtrArithmetic", "fatal error: checkptr: pointer arithmetic result points to invalid allocation\n"},
+		{"CheckPtrSize", "fatal error: checkptr: converted pointer straddles multiple allocations\n"},
+		{"CheckPtrSmall", "fatal error: checkptr: pointer arithmetic computed bad pointer value\n"},
 	}
 
 	for _, tc := range testCases {

src/runtime/crash_unix_test.go

@@ -15,6 +15,7 @@ import (
 	"os/exec"
 	"path/filepath"
 	"runtime"
+	"strings"
 	"sync"
 	"syscall"
 	"testing"
@@ -288,6 +289,12 @@ func TestSignalExitStatus(t *testing.T) {
 }
 
 func TestSignalIgnoreSIGTRAP(t *testing.T) {
+	if runtime.GOOS == "openbsd" {
+		if bn := testenv.Builder(); strings.HasSuffix(bn, "-62") || strings.HasSuffix(bn, "-64") {
+			testenv.SkipFlaky(t, 17496)
+		}
+	}
+
 	output := runTestProg(t, "testprognet", "SignalIgnoreSIGTRAP")
 	want := "OK\n"
 	if output != want {