cmd/compile/internal/gc: various minor cleanups

Two funcs and a field were unused. Remove them.

A few statements could be made simpler.

importsym's pos parameter was unused, so remove it.

Finally, don't use printf-like funcs with constant strings that have no
formatting directives.

Change-Id: I415452249bf2168aa353ac4f3643dfc03017ee53
Reviewed-on: https://go-review.googlesource.com/117699
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>

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

@@ -227,17 +227,6 @@ type bvecSet struct {
 	uniq  []bvec // unique bvecs, in insertion order
 }
 
-func newBvecSet(size int) bvecSet {
-	// bvecSet is a linear probing hash table.
-	// The hash table has 4n entries to keep the linear
-	// scan short.
-	index := make([]int, size*4)
-	for i := range index {
-		index[i] = -1
-	}
-	return bvecSet{index, nil}
-}
-
 func (m *bvecSet) grow() {
 	// Allocate new index.
 	n := len(m.index) * 2

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

@@ -766,7 +766,7 @@ func evconst(n *Node) {
 			v.U.(*Mpint).Neg()
 
 		case OCOM_ | CTINT_:
-			var et types.EType = Txxx
+			et := Txxx
 			if nl.Type != nil {
 				et = nl.Type.Etype
 			}

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

@@ -142,7 +142,7 @@ func assembleInlines(fnsym *obj.LSym, dwVars []*dwarf.Var) dwarf.InlCalls {
 				// return temps (~r%d) that were created during
 				// lowering, or unnamed params ("_").
 				v.ChildIndex = int32(synthCount)
-				synthCount += 1
+				synthCount++
 			}
 		}
 	}

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

@@ -88,7 +88,7 @@ func dumpexport(bout *bio.Writer) {
 	}
 }
 
-func importsym(ipkg *types.Pkg, pos src.XPos, s *types.Sym, op Op) *Node {
+func importsym(ipkg *types.Pkg, s *types.Sym, op Op) *Node {
 	n := asNode(s.PkgDef())
 	if n == nil {
 		// iimport should have created a stub ONONAME
@@ -113,7 +113,7 @@ func importsym(ipkg *types.Pkg, pos src.XPos, s *types.Sym, op Op) *Node {
 // If no such type has been declared yet, a forward declaration is returned.
 // ipkg is the package being imported
 func importtype(ipkg *types.Pkg, pos src.XPos, s *types.Sym) *types.Type {
-	n := importsym(ipkg, pos, s, OTYPE)
+	n := importsym(ipkg, s, OTYPE)
 	if n.Op != OTYPE {
 		t := types.New(TFORW)
 		t.Sym = s
@@ -135,7 +135,7 @@ func importtype(ipkg *types.Pkg, pos src.XPos, s *types.Sym) *types.Type {
 // importobj declares symbol s as an imported object representable by op.
 // ipkg is the package being imported
 func importobj(ipkg *types.Pkg, pos src.XPos, s *types.Sym, op Op, ctxt Class, t *types.Type) *Node {
-	n := importsym(ipkg, pos, s, op)
+	n := importsym(ipkg, s, op)
 	if n.Op != ONONAME {
 		if n.Op == op && (n.Class() != ctxt || !eqtype(n.Type, t)) {
 			redeclare(lineno, s, fmt.Sprintf("during import %q", ipkg.Path))

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

@@ -595,7 +595,7 @@ func (p *iexporter) typOff(t *types.Type) uint64 {
 	if !ok {
 		w := p.newWriter()
 		w.doTyp(t)
-		off = predeclReserved + uint64(w.flush())
+		off = predeclReserved + w.flush()
 		p.typIndex[t] = off
 	}
 	return off

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

@@ -341,7 +341,7 @@ func Main(archInit func(*Arch)) {
 			}
 			// display help about the -d option itself and quit
 			if name == "help" {
-				fmt.Printf(debugHelpHeader)
+				fmt.Print(debugHelpHeader)
 				maxLen := len("ssa/help")
 				for _, t := range debugtab {
 					if len(t.name) > maxLen {
@@ -353,7 +353,7 @@ func Main(archInit func(*Arch)) {
 				}
 				// ssa options have their own help
 				fmt.Printf("\t%-*s\t%s\n", maxLen, "ssa/help", "print help about SSA debugging")
-				fmt.Printf(debugHelpFooter)
+				fmt.Print(debugHelpFooter)
 				os.Exit(0)
 			}
 			val, valstring, haveInt := 1, "", true

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

@@ -299,8 +299,8 @@ func (a *Mpint) SetString(as string) {
 	}
 }
 
-func (x *Mpint) String() string {
-	return bconv(x, 0)
+func (a *Mpint) String() string {
+	return bconv(a, 0)
 }
 
 func bconv(xval *Mpint, flag FmtFlag) string {

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

@@ -350,7 +350,6 @@ type scopexplainContext struct {
 	dwarfData   *dwarf.Data
 	dwarfReader *dwarf.Reader
 	scopegen    int
-	lines       map[line][]int
 }
 
 // readScope reads the DW_TAG_lexical_block or the DW_TAG_subprogram in

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

@@ -2220,14 +2220,6 @@ func callnew(t *types.Type) *Node {
 	return v
 }
 
-func iscallret(n *Node) bool {
-	if n == nil {
-		return false
-	}
-	n = outervalue(n)
-	return n.Op == OINDREGSP
-}
-
 // isReflectHeaderDataField reports whether l is an expression p.Data
 // where p has type reflect.SliceHeader or reflect.StringHeader.
 func isReflectHeaderDataField(l *Node) bool {