cmd/internal/obj: remove dead code and small cleanups

Change-Id: I88fa0cc245a2141af04acced8716e08b1133abd1
Reviewed-on: https://go-review.googlesource.com/14350Reviewed-by: Ian Lance Taylor <iant@golang.org>

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

@@ -319,6 +319,7 @@ func Main() {
 	dclcontext = PEXTERN
 	nerrors = 0
 	lexlineno = 1
+	const BOM = 0xFEFF
 
 	for _, infile = range flag.Args() {
 		linehistpush(infile)
@@ -338,7 +339,7 @@ func Main() {
 		curio.last = 0
 
 		// Skip initial BOM if present.
-		if obj.Bgetrune(curio.bin) != obj.BOM {
+		if obj.Bgetrune(curio.bin) != BOM {
 			obj.Bungetrune(curio.bin)
 		}
 
@@ -601,11 +602,11 @@ func findpkg(name string) (file string, ok bool) {
 		// if there is an array.6 in the array.a library,
 		// want to find all of array.a, not just array.6.
 		file = fmt.Sprintf("%s.a", name)
-		if obj.Access(file, 0) >= 0 {
+		if _, err := os.Stat(file); err == nil {
 			return file, true
 		}
 		file = fmt.Sprintf("%s.o", name)
-		if obj.Access(file, 0) >= 0 {
+		if _, err := os.Stat(file); err == nil {
 			return file, true
 		}
 		return "", false
@@ -623,11 +624,11 @@ func findpkg(name string) (file string, ok bool) {
 
 	for p := idirs; p != nil; p = p.link {
 		file = fmt.Sprintf("%s/%s.a", p.dir, name)
-		if obj.Access(file, 0) >= 0 {
+		if _, err := os.Stat(file); err == nil {
 			return file, true
 		}
 		file = fmt.Sprintf("%s/%s.o", p.dir, name)
-		if obj.Access(file, 0) >= 0 {
+		if _, err := os.Stat(file); err == nil {
 			return file, true
 		}
 	}
@@ -644,11 +645,11 @@ func findpkg(name string) (file string, ok bool) {
 		}
 
 		file = fmt.Sprintf("%s/pkg/%s_%s%s%s/%s.a", goroot, goos, goarch, suffixsep, suffix, name)
-		if obj.Access(file, 0) >= 0 {
+		if _, err := os.Stat(file); err == nil {
 			return file, true
 		}
 		file = fmt.Sprintf("%s/pkg/%s_%s%s%s/%s.o", goroot, goos, goarch, suffixsep, suffix, name)
-		if obj.Access(file, 0) >= 0 {
+		if _, err := os.Stat(file); err == nil {
 			return file, true
 		}
 	}

src/cmd/internal/obj/arm64/asm7.go

@@ -147,7 +147,6 @@ func OPBIT(x uint32) uint32 {
 const (
 	LFROM = 1 << 0
 	LTO   = 1 << 1
-	LPOOL = 1 << 2
 )
 
 var optab = []Optab{

src/cmd/internal/obj/data.go

@@ -239,21 +239,6 @@ func setaddr(ctxt *Link, s *LSym, off int64, t *LSym) int64 {
 	return setaddrplus(ctxt, s, off, t, 0)
 }
 
-func addsize(ctxt *Link, s *LSym, t *LSym) int64 {
-	if s.Type == 0 {
-		s.Type = SDATA
-	}
-	i := s.Size
-	s.Size += int64(ctxt.Arch.Ptrsize)
-	Symgrow(ctxt, s, s.Size)
-	r := Addrel(s)
-	r.Sym = t
-	r.Off = int32(i)
-	r.Siz = uint8(ctxt.Arch.Ptrsize)
-	r.Type = R_SIZE
-	return i + int64(r.Siz)
-}
-
 func addaddrplus4(ctxt *Link, s *LSym, t *LSym, add int64) int64 {
 	if s.Type == 0 {
 		s.Type = SDATA

src/cmd/internal/obj/fmt.go

@@ -17,18 +17,11 @@ package obj
 const (
 	FmtWidth = 1 << iota
 	FmtLeft
-	FmtPrec
 	FmtSharp
-	FmtSpace
 	FmtSign
-	FmtApost
-	FmtZero
 	FmtUnsigned
 	FmtShort
 	FmtLong
-	FmtVLong
 	FmtComma
 	FmtByte
-	FmtLDouble
-	FmtFlag
 )

src/cmd/internal/obj/funcdata.go

@@ -74,6 +74,5 @@ const (
 	PCDATA_StackMapIndex       = 0
 	FUNCDATA_ArgsPointerMaps   = 0
 	FUNCDATA_LocalsPointerMaps = 1
-	FUNCDATA_DeadValueMaps     = 2
 	ArgsSizeUnknown            = -0x80000000
 )

src/cmd/internal/obj/libc.go

-// Copyright 2015 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 obj
-
-const (
-	AEXIST = 0
-	BOM    = 0xFEFF
-)
-
-var GOEXPERIMENT string

src/cmd/internal/obj/mgc0.go

-// Copyright 2013 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 obj
-
-// Garbage collector liveness bitmap generation.
-
-// The command line flag -live causes this code to print debug information.
-// The levels are:
-//
-//	-live (aka -live=1): print liveness lists as code warnings at safe points
-//	-live=2: print an assembly listing with liveness annotations
-//	-live=3: print information during each computation phase (much chattier)
-//
-// Each level includes the earlier output as well.
-
-// Copyright 2012 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.
-
-// Used by cmd/gc.
-
-const (
-	InsData = 1 + iota
-	InsArray
-	InsArrayEnd
-	InsEnd
-	MaxGCMask = 65536
-)

src/cmd/internal/obj/objfile.go

@@ -107,8 +107,6 @@ import (
 	"strings"
 )
 
-var outfile string
-
 // The Go and C compilers, and the assembler, call writeobj to write
 // out a Go object file.  The linker does not call this; the linker
 // does not write out object files.

src/cmd/internal/obj/sym.go

@@ -107,12 +107,7 @@ func Linknew(arch *LinkArch) *Link {
 
 	// On arm, record goarm.
 	if ctxt.Arch.Thechar == '5' {
-		p := Getgoarm()
-		if p != "" {
-			ctxt.Goarm = int32(Atoi(p))
-		} else {
-			ctxt.Goarm = 6
-		}
+		ctxt.Goarm = Getgoarm()
 	}
 
 	return ctxt

src/cmd/internal/obj/util.go

@@ -11,7 +11,6 @@ import (
 	"io"
 	"log"
 	"os"
-	"strconv"
 	"strings"
 	"time"
 )
@@ -166,17 +165,6 @@ func Brdstr(b *Biobuf, delim int, cut int) string {
 	return s
 }
 
-func Access(name string, mode int) int {
-	if mode != 0 {
-		panic("bad access")
-	}
-	_, err := os.Stat(name)
-	if err != nil {
-		return -1
-	}
-	return 0
-}
-
 func Blinelen(b *Biobuf) int {
 	return b.linelen
 }
@@ -212,10 +200,14 @@ func Getgoos() string {
 	return envOr("GOOS", defaultGOOS)
 }
 
-func Getgoarm() string {
+func Getgoarm() int32 {
 	switch v := envOr("GOARM", defaultGOARM); v {
-	case "5", "6", "7":
-		return v
+	case "5":
+		return 5
+	case "6":
+		return 6
+	case "7":
+		return 7
 	}
 	// Fail here, rather than validate at multiple call sites.
 	log.Fatalf("Invalid GOARM value. Must be 5, 6, or 7.")
@@ -235,11 +227,6 @@ func Getgoversion() string {
 	return version
 }
 
-func Atoi(s string) int {
-	i, _ := strconv.Atoi(s)
-	return i
-}
-
 func (p *Prog) Line() string {
 	return p.Ctxt.LineHist.LineString(int(p.Lineno))
 }

src/cmd/internal/obj/x86/asm6.go

@@ -40,8 +40,6 @@ import (
 // Instruction layout.
 
 const (
-	MaxAlign = 32 // max data alignment
-
 	// Loop alignment constants:
 	// want to align loop entry to LoopAlign-byte boundary,
 	// and willing to insert at most MaxLoopPad bytes of NOP to do so.
@@ -175,7 +173,6 @@ const (
 	Zil_rp
 	Ziq_rp
 	Zilo_m
-	Ziqo_m
 	Zjmp
 	Zjmpcon
 	Zloop
@@ -225,14 +222,10 @@ const (
 	Py1 = 0x81 // symbolic; exact value doesn't matter
 	Py3 = 0x83 // symbolic; exact value doesn't matter
 
-	Rxf = 1 << 9 /* internal flag for Rxr on from */
-	Rxt = 1 << 8 /* internal flag for Rxr on to */
 	Rxw = 1 << 3 /* =1, 64-bit operand size */
 	Rxr = 1 << 2 /* extend modrm reg */
 	Rxx = 1 << 1 /* extend sib index */
 	Rxb = 1 << 0 /* extend modrm r/m, sib base, or opcode reg */
-
-	Maxand = 10 /* in -a output width of the byte codes */
 )
 
 var ycover [Ymax * Ymax]uint8
@@ -245,11 +238,6 @@ var ynone = []ytab{
 	{Ynone, Ynone, Ynone, Zlit, 1},
 }
 
-var ysahf = []ytab{
-	{Ynone, Ynone, Ynone, Zlit, 2},
-	{Ynone, Ynone, Ynone, Zlit, 1},
-}
-
 var ytext = []ytab{
 	{Ymb, Ynone, Ytextsize, Zpseudo, 0},
 	{Ymb, Yi32, Ytextsize, Zpseudo, 1},

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

@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"log"
 	"sort"
+	"strconv"
 	"strings"
 )
 
@@ -191,8 +192,8 @@ func ldpe(f *obj.Biobuf, pkg string, length int64, pn string) {
 		if peobj.sect[i].name[0] != '/' {
 			continue
 		}
-		l = uint32(obj.Atoi(peobj.sect[i].name[1:]))
-		peobj.sect[i].name = cstring(peobj.snames[l:])
+		n, _ := strconv.Atoi(peobj.sect[i].name[1:])
+		peobj.sect[i].name = cstring(peobj.snames[n:])
 	}
 
 	// read symbols

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

@@ -421,7 +421,7 @@ func loadinternal(name string) {
 			if Debug['v'] != 0 {
 				fmt.Fprintf(&Bso, "searching for %s.a in %s\n", name, shlibname)
 			}
-			if obj.Access(shlibname, obj.AEXIST) >= 0 {
+			if _, err := os.Stat(shlibname); err == nil {
 				addlibpath(Ctxt, "internal", "internal", "", name, shlibname)
 				found = 1
 				break
@@ -431,7 +431,7 @@ func loadinternal(name string) {
 		if Debug['v'] != 0 {
 			fmt.Fprintf(&Bso, "searching for %s.a in %s\n", name, pname)
 		}
-		if obj.Access(pname, obj.AEXIST) >= 0 {
+		if _, err := os.Stat(pname); err == nil {
 			addlibpath(Ctxt, "internal", "internal", pname, name, "")
 			found = 1
 			break

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

@@ -144,12 +144,7 @@ func linknew(arch *LinkArch) *Link {
 
 	// On arm, record goarm.
 	if ctxt.Arch.Thechar == '5' {
-		p := obj.Getgoarm()
-		if p != "" {
-			ctxt.Goarm = int32(obj.Atoi(p))
-		} else {
-			ctxt.Goarm = 6
-		}
+		ctxt.Goarm = obj.Getgoarm()
 	}
 
 	return ctxt