cmd/compile: implement fmt.Formatter for *Node formats %s, %v

Change-Id: I80ed668cdeab0c4342b734d34b429927e0213e5a
Reviewed-on: https://go-review.googlesource.com/28335Reviewed-by: Matthew Dempsky <mdempsky@google.com>

src/cmd/compile/internal/amd64/ggen.go

@@ -40,7 +40,7 @@ func defframe(ptxt *obj.Prog) {
 			gc.Fatalf("needzero class %d", n.Class)
 		}
 		if n.Type.Width%int64(gc.Widthptr) != 0 || n.Xoffset%int64(gc.Widthptr) != 0 || n.Type.Width == 0 {
-			gc.Fatalf("var %v has size %d offset %d", gc.Nconv(n, gc.FmtLong), int(n.Type.Width), int(n.Xoffset))
+			gc.Fatalf("var %2v has size %d offset %d", n, int(n.Type.Width), int(n.Xoffset))
 		}
 
 		if lo != hi && n.Xoffset+n.Type.Width >= lo-int64(2*gc.Widthreg) {

src/cmd/compile/internal/amd64/gsubr.go

@@ -178,7 +178,7 @@ func bignodes() {
  */
 func gmove(f *gc.Node, t *gc.Node) {
 	if gc.Debug['M'] != 0 {
-		fmt.Printf("gmove %v -> %v\n", gc.Nconv(f, gc.FmtLong), gc.Nconv(t, gc.FmtLong))
+		fmt.Printf("gmove %2v -> %2v\n", f, t)
 	}
 
 	ft := gc.Simsimtype(f.Type)

src/cmd/compile/internal/arm/ggen.go

@@ -34,7 +34,7 @@ func defframe(ptxt *obj.Prog) {
 			gc.Fatalf("needzero class %d", n.Class)
 		}
 		if n.Type.Width%int64(gc.Widthptr) != 0 || n.Xoffset%int64(gc.Widthptr) != 0 || n.Type.Width == 0 {
-			gc.Fatalf("var %v has size %d offset %d", gc.Nconv(n, gc.FmtLong), int(n.Type.Width), int(n.Xoffset))
+			gc.Fatalf("var %2v has size %d offset %d", n, int(n.Type.Width), int(n.Xoffset))
 		}
 		if lo != hi && n.Xoffset+n.Type.Width >= lo-int64(2*gc.Widthptr) {
 			// merge with range we already have

src/cmd/compile/internal/arm64/ggen.go

@@ -43,7 +43,7 @@ func defframe(ptxt *obj.Prog) {
 			gc.Fatalf("needzero class %d", n.Class)
 		}
 		if n.Type.Width%int64(gc.Widthptr) != 0 || n.Xoffset%int64(gc.Widthptr) != 0 || n.Type.Width == 0 {
-			gc.Fatalf("var %v has size %d offset %d", gc.Nconv(n, gc.FmtLong), int(n.Type.Width), int(n.Xoffset))
+			gc.Fatalf("var %2v has size %d offset %d", n, int(n.Type.Width), int(n.Xoffset))
 		}
 
 		if lo != hi && n.Xoffset+n.Type.Width >= lo-int64(2*gc.Widthreg) {

src/cmd/compile/internal/arm64/gsubr.go

@@ -133,7 +133,7 @@ func ginscmp(op gc.Op, t *gc.Type, n1, n2 *gc.Node, likely int) *obj.Prog {
  */
 func gmove(f *gc.Node, t *gc.Node) {
 	if gc.Debug['M'] != 0 {
-		fmt.Printf("gmove %v -> %v\n", gc.Nconv(f, gc.FmtLong), gc.Nconv(t, gc.FmtLong))
+		fmt.Printf("gmove %2v -> %2v\n", f, t)
 	}
 
 	ft := int(gc.Simsimtype(f.Type))

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

@@ -361,7 +361,7 @@ func cgen_wb(n, res *Node, wb bool) {
 	default:
 		Dump("cgen", n)
 		Dump("cgen-res", res)
-		Fatalf("cgen: unknown op %v", Nconv(n, FmtShort|FmtSign))
+		Fatalf("cgen: unknown op %+1v", n)
 
 	case OOROR, OANDAND,
 		OEQ, ONE,
@@ -1553,7 +1553,7 @@ func Agen(n *Node, res *Node) {
 	switch n.Op {
 	default:
 		Dump("bad agen", n)
-		Fatalf("agen: unknown op %v", Nconv(n, FmtShort|FmtSign))
+		Fatalf("agen: unknown op %+1v", n)
 
 	case OCALLMETH:
 		cgen_callmeth(n, 0)
@@ -1864,7 +1864,7 @@ func bgenx(n, res *Node, wantTrue bool, likely int, to *obj.Prog) {
 	case OLITERAL:
 		// n is a constant.
 		if !Isconst(n, CTBOOL) {
-			Fatalf("bgen: non-bool const %v\n", Nconv(n, FmtLong))
+			Fatalf("bgen: non-bool const %2v\n", n)
 		}
 		if genval {
 			Cgen(Nodbool(wantTrue == n.Val().U.(bool)), res)

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

@@ -107,7 +107,7 @@ func typecheckclosure(func_ *Node, top int) {
 		if !n.Name.Captured {
 			n.Name.Captured = true
 			if n.Name.Decldepth == 0 {
-				Fatalf("typecheckclosure: var %v does not have decldepth assigned", Nconv(n, FmtShort))
+				Fatalf("typecheckclosure: var %1v does not have decldepth assigned", n)
 			}
 
 			// Ignore assignments to the variable in straightline code
@@ -193,7 +193,7 @@ func closurename(n *Node) *Sym {
 		n.Func.Outerfunc.Func.Closgen++
 		gen = n.Func.Outerfunc.Func.Closgen
 	default:
-		Fatalf("closurename called for %v", Nconv(n, FmtShort))
+		Fatalf("closurename called for %1v", n)
 	}
 	n.Sym = Lookupf("%s.%s%d", outer, prefix, gen)
 	return n.Sym

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

@@ -1386,7 +1386,7 @@ func defaultlitreuse(n *Node, t *Type, reuse canReuseNode) *Node {
 		Yyerror("defaultlit: unknown literal: %v", n)
 
 	case CTxxx:
-		Fatalf("defaultlit: idealkind is CTxxx: %v", Nconv(n, FmtSign))
+		Fatalf("defaultlit: idealkind is CTxxx: %+v", n)
 
 	case CTBOOL:
 		t1 := Types[TBOOL]

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

@@ -260,7 +260,7 @@ var classnames = []string{
 func (n *Node) Format(s fmt.State, format rune) {
 	switch format {
 	case 's', 'v':
-		fmt.Fprint(s, Nconv(n, fmtFlag(s)))
+		n.Nconv(s)
 
 	case 'j':
 		n.jconv(s)
@@ -866,7 +866,7 @@ func (p *printer) stmtfmt(n *Node) *printer {
 		if n.Left != nil {
 			p.f("%v %v", n.Left, n.Right)
 		} else {
-			p.Nconv(n.Right, 0)
+			p.f("%v", n.Right)
 		}
 
 	// Don't export "v = <N>" initializing statements, hope they're always
@@ -972,7 +972,7 @@ func (p *printer) stmtfmt(n *Node) *printer {
 			p.f(" %v;", n.Ninit.First())
 		}
 		if n.Left != nil {
-			p.f(" %s ", Nconv(n.Left, 0))
+			p.f(" %v ", n.Left)
 		}
 
 		p.f(" { %v }", n.List)
@@ -1543,10 +1543,10 @@ func (p *printer) nodedump(n *Node, flag FmtFlag) *printer {
 
 	if recur {
 		if n.Left != nil {
-			p.Nconv(n.Left, 0)
+			p.f("%v", n.Left)
 		}
 		if n.Right != nil {
-			p.Nconv(n.Right, 0)
+			p.f("%v", n.Right)
 		}
 		if n.List.Len() != 0 {
 			p.indent()
@@ -1649,7 +1649,7 @@ func Fldconv(f *Field, flag FmtFlag) string {
 
 		if s != nil && f.Embedded == 0 {
 			if f.Funarg != FunargNone {
-				name = Nconv(f.Nname, 0)
+				name = f.Nname.String()
 			} else if flag&FmtLong != 0 {
 				name = fmt.Sprintf("%01v", s)
 				if !exportname(name) && flag&FmtUnsigned == 0 {
@@ -1735,37 +1735,31 @@ func (t *Type) tconv(s fmt.State) {
 	t.Trecur--
 }
 
-func (n *Node) Print(p *printer) {
-	p.Nconv(n, 0)
-}
-
-var _ Printable = new(Node) // verify that Node implements Printable
-
 func (n *Node) String() string {
-	return Nconv(n, 0)
+	return fmt.Sprint(n)
 }
 
 // Fmt '%N': Nodes.
 // Flags: 'l' suffix with "(type %T)" where possible
 //	  '+h' in debug mode, don't recurse, no multiline output
-func Nconv(n *Node, flag FmtFlag) string {
-	return new(printer).Nconv(n, flag).String()
-}
+func (n *Node) Nconv(s fmt.State) {
+	flag := fmtFlag(s)
 
-func (p *printer) Nconv(n *Node, flag FmtFlag) *printer {
 	if n == nil {
-		return p.s("<N>")
+		fmt.Fprint(s, "<N>")
+		return
 	}
+
 	sf := flag
 	sm := setfmode(&flag)
 
 	switch fmtmode {
 	case FErr:
-		p.nodefmt(n, flag)
+		fmt.Fprint(s, new(printer).nodefmt(n, flag).String())
 
 	case FDbg:
 		dumpdepth++
-		p.nodedump(n, flag)
+		fmt.Fprint(s, new(printer).nodedump(n, flag).String())
 		dumpdepth--
 
 	default:
@@ -1774,8 +1768,6 @@ func (p *printer) Nconv(n *Node, flag FmtFlag) *printer {
 
 	flag = sf
 	fmtmode = sm
-
-	return p
 }
 
 func (n Nodes) Print(p *printer) {
@@ -1809,7 +1801,7 @@ func (p *printer) hconv(l Nodes, flag FmtFlag) *printer {
 	}
 
 	for i, n := range l.Slice() {
-		p.Nconv(n, 0)
+		p.f("%v", n)
 		if i+1 < l.Len() {
 			p.s(sep)
 		}
@@ -1826,7 +1818,7 @@ func dumplist(s string, l Nodes) {
 }
 
 func Dump(s string, n *Node) {
-	fmt.Printf("%s [%p]%v\n", s, n, Nconv(n, FmtSign))
+	fmt.Printf("%s [%p]%+v\n", s, n, n)
 }
 
 // printer is a buffer for creating longer formatted strings.

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

@@ -716,7 +716,7 @@ func gen(n *Node) {
 
 	switch n.Op {
 	default:
-		Fatalf("gen: unknown op %v", Nconv(n, FmtShort|FmtSign))
+		Fatalf("gen: unknown op %+1v", n)
 
 	case OCASE,
 		OFALL,

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

@@ -40,7 +40,7 @@ func fnpkg(fn *Node) *Pkg {
 			rcvr = rcvr.Elem()
 		}
 		if rcvr.Sym == nil {
-			Fatalf("receiver with no sym: [%v] %v  (%v)", fn.Sym, Nconv(fn, FmtLong), rcvr)
+			Fatalf("receiver with no sym: [%v] %2v  (%v)", fn.Sym, fn, rcvr)
 		}
 		return rcvr.Sym.Pkg
 	}
@@ -65,7 +65,7 @@ func typecheckinl(fn *Node) {
 	}
 
 	if Debug['m'] > 2 || Debug_export != 0 {
-		fmt.Printf("typecheck import [%v] %v { %v }\n", fn.Sym, Nconv(fn, FmtLong), hconv(fn.Func.Inl, FmtSharp))
+		fmt.Printf("typecheck import [%v] %2v { %v }\n", fn.Sym, fn, hconv(fn.Func.Inl, FmtSharp))
 	}
 
 	save_safemode := safemode
@@ -89,7 +89,7 @@ func caninl(fn *Node) {
 		Fatalf("caninl %v", fn)
 	}
 	if fn.Func.Nname == nil {
-		Fatalf("caninl no nname %v", Nconv(fn, FmtSign))
+		Fatalf("caninl no nname %+v", fn)
 	}
 
 	var reason string // reason, if any, that the function was not inlined
@@ -165,7 +165,7 @@ func caninl(fn *Node) {
 	fn.Type.SetNname(n)
 
 	if Debug['m'] > 1 {
-		fmt.Printf("%v: can inline %v as: %#v { %v }\n", fn.Line(), Nconv(n, FmtSharp), fn.Type, hconv(n.Func.Inl, FmtSharp))
+		fmt.Printf("%v: can inline %#v as: %#v { %v }\n", fn.Line(), n, fn.Type, hconv(n.Func.Inl, FmtSharp))
 	} else if Debug['m'] != 0 {
 		fmt.Printf("%v: can inline %v\n", fn.Line(), n)
 	}
@@ -211,7 +211,7 @@ func ishairy(n *Node, budget *int32, reason *string) bool {
 	case OCALLMETH:
 		t := n.Left.Type
 		if t == nil {
-			Fatalf("no function type for [%p] %v\n", n.Left, Nconv(n.Left, FmtSign))
+			Fatalf("no function type for [%p] %+v\n", n.Left, n.Left)
 		}
 		if t.Nname() == nil {
 			Fatalf("no function definition for [%p] %+v\n", t, t)
@@ -327,7 +327,7 @@ func inlconv2expr(n *Node) *Node {
 // statements.
 func inlconv2list(n *Node) []*Node {
 	if n.Op != OINLCALL || n.Rlist.Len() == 0 {
-		Fatalf("inlconv2list %v\n", Nconv(n, FmtSign))
+		Fatalf("inlconv2list %+v\n", n)
 	}
 
 	s := n.Rlist.Slice()
@@ -475,7 +475,7 @@ func inlnode(n *Node) *Node {
 	switch n.Op {
 	case OCALLFUNC:
 		if Debug['m'] > 3 {
-			fmt.Printf("%v:call to func %v\n", n.Line(), Nconv(n.Left, FmtSign))
+			fmt.Printf("%v:call to func %+v\n", n.Line(), n.Left)
 		}
 		if n.Left.Func != nil && n.Left.Func.Inl.Len() != 0 && !isIntrinsicCall(n) { // normal case
 			n = mkinlcall(n, n.Left, n.Isddd)
@@ -485,12 +485,12 @@ func inlnode(n *Node) *Node {
 
 	case OCALLMETH:
 		if Debug['m'] > 3 {
-			fmt.Printf("%v:call to meth %v\n", n.Line(), Nconv(n.Left.Right, FmtLong))
+			fmt.Printf("%v:call to meth %2v\n", n.Line(), n.Left.Right)
 		}
 
 		// typecheck should have resolved ODOTMETH->type, whose nname points to the actual function.
 		if n.Left.Type == nil {
-			Fatalf("no function type for [%p] %v\n", n.Left, Nconv(n.Left, FmtSign))
+			Fatalf("no function type for [%p] %+v\n", n.Left, n.Left)
 		}
 
 		if n.Left.Type.Nname() == nil {
@@ -562,7 +562,7 @@ func mkinlcall1(n *Node, fn *Node, isddd bool) *Node {
 	}
 
 	if Debug['m'] > 2 {
-		fmt.Printf("%v: Before inlining: %v\n", n.Line(), Nconv(n, FmtSign))
+		fmt.Printf("%v: Before inlining: %+v\n", n.Line(), n)
 	}
 
 	ninit := n.Ninit
@@ -623,10 +623,10 @@ func mkinlcall1(n *Node, fn *Node, isddd bool) *Node {
 			Fatalf("missing inlvar for %v\n", t.Nname)
 		}
 		if n.Left.Left == nil {
-			Fatalf("method call without receiver: %v", Nconv(n, FmtSign))
+			Fatalf("method call without receiver: %+v", n)
 		}
 		if t == nil {
-			Fatalf("method call unknown receiver type: %v", Nconv(n, FmtSign))
+			Fatalf("method call unknown receiver type: %+v", n)
 		}
 		as := Nod(OAS, tinlvar(t), n.Left.Left)
 		if as != nil {
@@ -682,7 +682,7 @@ func mkinlcall1(n *Node, fn *Node, isddd bool) *Node {
 	if fn.Type.Recv() != nil && n.Left.Op != ODOTMETH {
 		// non-method call to method
 		if n.List.Len() == 0 {
-			Fatalf("non-method call to method without first arg: %v", Nconv(n, FmtSign))
+			Fatalf("non-method call to method without first arg: %+v", n)
 		}
 
 		// append receiver inlvar to LHS.
@@ -692,7 +692,7 @@ func mkinlcall1(n *Node, fn *Node, isddd bool) *Node {
 			Fatalf("missing inlvar for %v\n", t.Nname)
 		}
 		if t == nil {
-			Fatalf("method call unknown receiver type: %v", Nconv(n, FmtSign))
+			Fatalf("method call unknown receiver type: %+v", n)
 		}
 		as.List.Append(tinlvar(t))
 		li++
@@ -843,7 +843,7 @@ func mkinlcall1(n *Node, fn *Node, isddd bool) *Node {
 	fn.Func.Inl.Set(body)
 
 	if Debug['m'] > 2 {
-		fmt.Printf("%v: After inlining %v\n\n", n.Line(), Nconv(n, FmtSign))
+		fmt.Printf("%v: After inlining %+v\n\n", n.Line(), n)
 	}
 
 	return n
@@ -854,7 +854,7 @@ func mkinlcall1(n *Node, fn *Node, isddd bool) *Node {
 // PPARAM's, PAUTOS and PPARAMOUTs of the called function.
 func inlvar(var_ *Node) *Node {
 	if Debug['m'] > 3 {
-		fmt.Printf("inlvar %v\n", Nconv(var_, FmtSign))
+		fmt.Printf("inlvar %+v\n", var_)
 	}
 
 	n := newname(var_.Sym)
@@ -923,13 +923,13 @@ func (subst *inlsubst) node(n *Node) *Node {
 	case ONAME:
 		if n.Name.Inlvar != nil { // These will be set during inlnode
 			if Debug['m'] > 2 {
-				fmt.Printf("substituting name %v  ->  %v\n", Nconv(n, FmtSign), Nconv(n.Name.Inlvar, FmtSign))
+				fmt.Printf("substituting name %+v  ->  %+v\n", n, n.Name.Inlvar)
 			}
 			return n.Name.Inlvar
 		}
 
 		if Debug['m'] > 2 {
-			fmt.Printf("not substituting name %v\n", Nconv(n, FmtSign))
+			fmt.Printf("not substituting name %+v\n", n)
 		}
 		return n
 
@@ -978,7 +978,7 @@ func (subst *inlsubst) node(n *Node) *Node {
 		m.Ninit.Set(nil)
 
 		if n.Op == OCLOSURE {
-			Fatalf("cannot inline function containing closure: %v", Nconv(n, FmtSign))
+			Fatalf("cannot inline function containing closure: %+v", n)
 		}
 
 		m.Left = subst.node(n.Left)

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

@@ -1233,7 +1233,7 @@ func livenessepilogue(lv *Liveness) {
 						if !n.Name.Needzero {
 							n.Name.Needzero = true
 							if debuglive >= 1 {
-								Warnl(p.Lineno, "%v: %v is ambiguously live", Curfn.Func.Nname, Nconv(n, FmtLong))
+								Warnl(p.Lineno, "%v: %2v is ambiguously live", Curfn.Func.Nname, n)
 							}
 
 							// Record in 'ambiguous' bitmap.
@@ -1329,7 +1329,7 @@ func livenessepilogue(lv *Liveness) {
 						}
 						n := lv.vars[j]
 						if n.Class != PPARAM {
-							yyerrorl(p.Lineno, "internal error: %v %v recorded as live on entry, p.Pc=%v", Curfn.Func.Nname, Nconv(n, FmtLong), p.Pc)
+							yyerrorl(p.Lineno, "internal error: %v %2v recorded as live on entry, p.Pc=%v", Curfn.Func.Nname, n, p.Pc)
 						}
 					}
 				}

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

@@ -746,7 +746,7 @@ func mergetemp(firstp *obj.Prog) {
 	nfree := len(bystart)
 	for _, v := range bystart {
 		if debugmerge > 0 && Debug['v'] != 0 {
-			fmt.Printf("consider %v: removed=%t\n", Nconv(v.node, FmtSharp), v.removed)
+			fmt.Printf("consider %#v: removed=%t\n", v.node, v.removed)
 		}
 
 		if v.removed {
@@ -761,7 +761,7 @@ func mergetemp(firstp *obj.Prog) {
 		}
 
 		if debugmerge > 0 && Debug['v'] != 0 {
-			fmt.Printf("consider %v: removed=%t nfree=%d nvar=%d\n", Nconv(v.node, FmtSharp), v.removed, nfree, len(bystart))
+			fmt.Printf("consider %#v: removed=%t nfree=%d nvar=%d\n", v.node, v.removed, nfree, len(bystart))
 		}
 
 		// Find old temp to reuse if possible.
@@ -770,7 +770,7 @@ func mergetemp(firstp *obj.Prog) {
 		for j := nfree; j < len(inuse); j++ {
 			v1 := inuse[j]
 			if debugmerge > 0 && Debug['v'] != 0 {
-				fmt.Printf("consider %v: maybe %v: type=%v,%v addrtaken=%v,%v\n", Nconv(v.node, FmtSharp), Nconv(v1.node, FmtSharp), t, v1.node.Type, v.node.Addrtaken, v1.node.Addrtaken)
+				fmt.Printf("consider %#v: maybe %#v: type=%v,%v addrtaken=%v,%v\n", v.node, v1.node, t, v1.node.Type, v.node.Addrtaken, v1.node.Addrtaken)
 			}
 
 			// Require the types to match but also require the addrtaken bits to match.
@@ -806,7 +806,7 @@ func mergetemp(firstp *obj.Prog) {
 	if debugmerge > 0 && Debug['v'] != 0 {
 		fmt.Printf("%v [%d - %d]\n", Curfn.Func.Nname.Sym, len(vars), nkill)
 		for _, v := range vars {
-			fmt.Printf("var %v %v %d-%d", Nconv(v.node, FmtSharp), v.node.Type, v.start, v.end)
+			fmt.Printf("var %#v %v %d-%d", v.node, v.node.Type, v.start, v.end)
 			if v.addr {
 				fmt.Printf(" addr=true")
 			}
@@ -814,7 +814,7 @@ func mergetemp(firstp *obj.Prog) {
 				fmt.Printf(" removed=true")
 			}
 			if v.merge != nil {
-				fmt.Printf(" merge %v", Nconv(v.merge.node, FmtSharp))
+				fmt.Printf(" merge %#v", v.merge.node)
 			}
 			if v.start == v.end && v.def != nil {
 				fmt.Printf(" %v", v.def.Prog)

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

@@ -48,7 +48,7 @@ func typecheckrange(n *Node) {
 	toomany = 0
 	switch t.Etype {
 	default:
-		Yyerror("cannot range over %v", Nconv(n.Right, FmtLong))
+		Yyerror("cannot range over %2v", n.Right)
 		goto out
 
 	case TARRAY, TSLICE:
@@ -104,7 +104,7 @@ func typecheckrange(n *Node) {
 		if v1.Name != nil && v1.Name.Defn == n {
 			v1.Type = t1
 		} else if v1.Type != nil && assignop(t1, v1.Type, &why) == 0 {
-			Yyerror("cannot assign type %v to %v in range%s", t1, Nconv(v1, FmtLong), why)
+			Yyerror("cannot assign type %v to %2v in range%s", t1, v1, why)
 		}
 		checkassign(n, v1)
 	}
@@ -113,7 +113,7 @@ func typecheckrange(n *Node) {
 		if v2.Name != nil && v2.Name.Defn == n {
 			v2.Type = t2
 		} else if v2.Type != nil && assignop(t2, v2.Type, &why) == 0 {
-			Yyerror("cannot assign type %v to %v in range%s", t2, Nconv(v2, FmtLong), why)
+			Yyerror("cannot assign type %v to %2v in range%s", t2, v2, why)
 		}
 		checkassign(n, v2)
 	}

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

@@ -393,10 +393,10 @@ func mkvar(f *Flow, a *obj.Addr) Bits {
 
 	if nvar >= NVAR {
 		if Debug['w'] > 1 && node != nil {
-			Fatalf("variable not optimized: %v", Nconv(node, FmtSharp))
+			Fatalf("variable not optimized: %#v", node)
 		}
 		if Debug['v'] > 0 {
-			Warn("variable not optimized: %v", Nconv(node, FmtSharp))
+			Warn("variable not optimized: %#v", node)
 		}
 
 		// If we're not tracking a word in a variable, mark the rest as
@@ -488,7 +488,7 @@ func mkvar(f *Flow, a *obj.Addr) Bits {
 	}
 
 	if Debug['R'] != 0 {
-		fmt.Printf("bit=%2d et=%v w=%d+%d %v %v flag=%d\n", i, et, o, w, Nconv(node, FmtSharp), Ctxt.Dconv(a), v.addr)
+		fmt.Printf("bit=%2d et=%v w=%d+%d %#v %v flag=%d\n", i, et, o, w, node, Ctxt.Dconv(a), v.addr)
 	}
 	Ostats.Nvar++
 

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

@@ -201,7 +201,7 @@ func init2(n *Node, out *[]*Node) {
 	}
 
 	if n.Op == ONAME && n.Ninit.Len() != 0 {
-		Fatalf("name %v with ninit: %v\n", n.Sym, Nconv(n, FmtSign))
+		Fatalf("name %v with ninit: %+v\n", n.Sym, n)
 	}
 
 	init1(n, out)

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

@@ -1013,7 +1013,7 @@ func assignconvfn(n *Node, t *Type, context func() string) *Node {
 	var why string
 	op := assignop(n.Type, t, &why)
 	if op == 0 {
-		Yyerror("cannot use %v as type %v in %s%s", Nconv(n, FmtLong), t, context(), why)
+		Yyerror("cannot use %2v as type %v in %s%s", n, t, context(), why)
 		op = OCONV
 	}
 

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

@@ -71,7 +71,7 @@ func typecheckswitch(n *Node) {
 		n.Left.Right = typecheck(n.Left.Right, Erv)
 		t = n.Left.Right.Type
 		if t != nil && !t.IsInterface() {
-			Yyerror("cannot type switch on non-interface value %v", Nconv(n.Left.Right, FmtLong))
+			Yyerror("cannot type switch on non-interface value %2v", n.Left.Right)
 		}
 	} else {
 		// expression switch
@@ -86,14 +86,14 @@ func typecheckswitch(n *Node) {
 		if t != nil {
 			switch {
 			case !okforeq[t.Etype]:
-				Yyerror("cannot switch on %v", Nconv(n.Left, FmtLong))
+				Yyerror("cannot switch on %2v", n.Left)
 			case t.IsSlice():
 				nilonly = "slice"
 			case t.IsArray() && !t.IsComparable():
-				Yyerror("cannot switch on %v", Nconv(n.Left, FmtLong))
+				Yyerror("cannot switch on %2v", n.Left)
 			case t.IsStruct():
 				if f := t.IncomparableField(); f != nil {
-					Yyerror("cannot switch on %v (struct containing %v cannot be compared)", Nconv(n.Left, FmtLong), f.Type)
+					Yyerror("cannot switch on %2v (struct containing %v cannot be compared)", n.Left, f.Type)
 				}
 			case t.Etype == TFUNC:
 				nilonly = "func"
@@ -143,7 +143,7 @@ func typecheckswitch(n *Node) {
 					case nilonly != "" && !isnil(n1):
 						Yyerror("invalid case %v in switch (can only compare %s %v to nil)", n1, nilonly, n.Left)
 					case t.IsInterface() && !n1.Type.IsInterface() && !n1.Type.IsComparable():
-						Yyerror("invalid case %v in switch (incomparable type)", Nconv(n1, FmtLong))
+						Yyerror("invalid case %2v in switch (incomparable type)", n1)
 					}
 
 				// type switch
@@ -159,15 +159,15 @@ func typecheckswitch(n *Node) {
 							niltype = ncase
 						}
 					case n1.Op != OTYPE && n1.Type != nil: // should this be ||?
-						Yyerror("%v is not a type", Nconv(n1, FmtLong))
+						Yyerror("%2v is not a type", n1)
 						// reset to original type
 						n1 = n.Left.Right
 						ls[i1] = n1
 					case !n1.Type.IsInterface() && t.IsInterface() && !implements(n1.Type, t, &missing, &have, &ptr):
 						if have != nil && !missing.Broke && !have.Broke {
-							Yyerror("impossible type switch case: %v cannot have dynamic type %v"+" (wrong type for %v method)\n\thave %v%1v\n\twant %v%1v", Nconv(n.Left.Right, FmtLong), n1.Type, missing.Sym, have.Sym, have.Type, missing.Sym, missing.Type)
+							Yyerror("impossible type switch case: %2v cannot have dynamic type %v"+" (wrong type for %v method)\n\thave %v%1v\n\twant %v%1v", n.Left.Right, n1.Type, missing.Sym, have.Sym, have.Type, missing.Sym, missing.Type)
 						} else if !missing.Broke {
-							Yyerror("impossible type switch case: %v cannot have dynamic type %v"+" (missing %v method)", Nconv(n.Left.Right, FmtLong), n1.Type, missing.Sym)
+							Yyerror("impossible type switch case: %2v cannot have dynamic type %v"+" (missing %v method)", n.Left.Right, n1.Type, missing.Sym)
 						}
 					}
 				}

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

@@ -490,7 +490,7 @@ OpSwitch:
 
 		if !t.IsPtr() {
 			if top&(Erv|Etop) != 0 {
-				Yyerror("invalid indirect of %v", Nconv(n.Left, FmtLong))
+				Yyerror("invalid indirect of %2v", n.Left)
 				n.Type = nil
 				return n
 			}
@@ -1380,7 +1380,7 @@ OpSwitch:
 		break OpSwitch
 
 	badcall1:
-		Yyerror("invalid argument %v for %v", Nconv(n.Left, FmtLong), n.Op)
+		Yyerror("invalid argument %2v for %v", n.Left, n.Op)
 		n.Type = nil
 		return n
 
@@ -1681,7 +1681,7 @@ OpSwitch:
 		n.Op = convertop(t, n.Type, &why)
 		if n.Op == 0 {
 			if n.Diag == 0 && !n.Type.Broke {
-				Yyerror("cannot convert %v to type %v%s", Nconv(n.Left, FmtLong), n.Type, why)
+				Yyerror("cannot convert %2v to type %v%s", n.Left, n.Type, why)
 				n.Diag = 1
 			}
 
@@ -2006,7 +2006,7 @@ OpSwitch:
 		if n.Left != nil {
 			t := n.Left.Type
 			if t != nil && !t.IsBoolean() {
-				Yyerror("non-bool %v used as for condition", Nconv(n.Left, FmtLong))
+				Yyerror("non-bool %2v used as for condition", n.Left)
 			}
 		}
 		n.Right = typecheck(n.Right, Etop)
@@ -2021,7 +2021,7 @@ OpSwitch:
 		if n.Left != nil {
 			t := n.Left.Type
 			if t != nil && !t.IsBoolean() {
-				Yyerror("non-bool %v used as if condition", Nconv(n.Left, FmtLong))
+				Yyerror("non-bool %2v used as if condition", n.Left)
 			}
 		}
 		typecheckslice(n.Nbody.Slice(), Etop)
@@ -2466,7 +2466,7 @@ func lookdot(n *Node, t *Type, dostrcmp int) *Field {
 				n.Left.Implicit = true
 				n.Left = typecheck(n.Left, Etype|Erv)
 			} else if tt.Etype == Tptr && tt.Elem().Etype == Tptr && Eqtype(derefall(tt), derefall(rcvr)) {
-				Yyerror("calling method %v with receiver %v requires explicit dereference", n.Sym, Nconv(n.Left, FmtLong))
+				Yyerror("calling method %v with receiver %2v requires explicit dereference", n.Sym, n.Left)
 				for tt.Etype == Tptr {
 					// Stop one level early for method with pointer receiver.
 					if rcvr.Etype == Tptr && tt.Elem().Etype != Tptr {
@@ -3250,7 +3250,7 @@ func checkassignto(src *Type, dst *Node) {
 	var why string
 
 	if assignop(src, dst.Type, &why) == 0 {
-		Yyerror("cannot assign %v to %v in multiple assignment%s", src, Nconv(dst, FmtLong), why)
+		Yyerror("cannot assign %v to %2v in multiple assignment%s", src, dst, why)
 		return
 	}
 }
@@ -3669,7 +3669,7 @@ func typecheckdef(n *Node) *Node {
 			}
 
 			if !e.Type.IsUntyped() && !Eqtype(t, e.Type) {
-				Yyerror("cannot use %v as type %v in const initializer", Nconv(e, FmtLong), t)
+				Yyerror("cannot use %2v as type %v in const initializer", e, t)
 				goto ret
 			}
 

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

@@ -184,7 +184,7 @@ func walkstmt(n *Node) *Node {
 		ORECOVER,
 		OGETG:
 		if n.Typecheck == 0 {
-			Fatalf("missing typecheck: %v", Nconv(n, FmtSign))
+			Fatalf("missing typecheck: %+v", n)
 		}
 		wascopy := n.Op == OCOPY
 		init := n.Ninit
@@ -199,7 +199,7 @@ func walkstmt(n *Node) *Node {
 	// the value received.
 	case ORECV:
 		if n.Typecheck == 0 {
-			Fatalf("missing typecheck: %v", Nconv(n, FmtSign))
+			Fatalf("missing typecheck: %+v", n)
 		}
 		init := n.Ninit
 		n.Ninit.Set(nil)
@@ -366,7 +366,7 @@ func walkstmt(n *Node) *Node {
 	}
 
 	if n.Op == ONAME {
-		Fatalf("walkstmt ended up with name: %v", Nconv(n, FmtSign))
+		Fatalf("walkstmt ended up with name: %+v", n)
 	}
 	return n
 }
@@ -500,7 +500,7 @@ func walkexpr(n *Node, init *Nodes) *Node {
 	}
 
 	if n.Typecheck != 1 {
-		Fatalf("missed typecheck: %v\n", Nconv(n, FmtSign))
+		Fatalf("missed typecheck: %+v", n)
 	}
 
 	if n.Op == ONAME && n.Class == PAUTOHEAP {
@@ -515,7 +515,7 @@ opswitch:
 	switch n.Op {
 	default:
 		Dump("walk", n)
-		Fatalf("walkexpr: switch 1 unknown op %v", Nconv(n, FmtShort|FmtSign))
+		Fatalf("walkexpr: switch 1 unknown op %+1v", n)
 
 	case OTYPE,
 		ONONAME,
@@ -2217,7 +2217,7 @@ func needwritebarrier(l *Node, r *Node) bool {
 func applywritebarrier(n *Node) *Node {
 	if n.Left != nil && n.Right != nil && needwritebarrier(n.Left, n.Right) {
 		if Debug_wb > 1 {
-			Warnl(n.Lineno, "marking %v for barrier", Nconv(n.Left, 0))
+			Warnl(n.Lineno, "marking %v for barrier", n.Left)
 		}
 		n.Op = OASWB
 		return n

src/cmd/compile/internal/mips64/ggen.go

@@ -36,7 +36,7 @@ func defframe(ptxt *obj.Prog) {
 			gc.Fatalf("needzero class %d", n.Class)
 		}
 		if n.Type.Width%int64(gc.Widthptr) != 0 || n.Xoffset%int64(gc.Widthptr) != 0 || n.Type.Width == 0 {
-			gc.Fatalf("var %v has size %d offset %d", gc.Nconv(n, gc.FmtLong), int(n.Type.Width), int(n.Xoffset))
+			gc.Fatalf("var %2v has size %d offset %d", n, int(n.Type.Width), int(n.Xoffset))
 		}
 
 		if lo != hi && n.Xoffset+n.Type.Width >= lo-int64(2*gc.Widthreg) {

src/cmd/compile/internal/mips64/gsubr.go

@@ -215,7 +215,7 @@ func bignodes() {
  */
 func gmove(f *gc.Node, t *gc.Node) {
 	if gc.Debug['M'] != 0 {
-		fmt.Printf("gmove %v -> %v\n", gc.Nconv(f, gc.FmtLong), gc.Nconv(t, gc.FmtLong))
+		fmt.Printf("gmove %2v -> %2v\n", f, t)
 	}
 
 	ft := int(gc.Simsimtype(f.Type))

src/cmd/compile/internal/ppc64/ggen.go

@@ -36,7 +36,7 @@ func defframe(ptxt *obj.Prog) {
 			gc.Fatalf("needzero class %d", n.Class)
 		}
 		if n.Type.Width%int64(gc.Widthptr) != 0 || n.Xoffset%int64(gc.Widthptr) != 0 || n.Type.Width == 0 {
-			gc.Fatalf("var %v has size %d offset %d", gc.Nconv(n, gc.FmtLong), int(n.Type.Width), int(n.Xoffset))
+			gc.Fatalf("var %2v has size %d offset %d", n, int(n.Type.Width), int(n.Xoffset))
 		}
 
 		if lo != hi && n.Xoffset+n.Type.Width >= lo-int64(2*gc.Widthreg) {

src/cmd/compile/internal/ppc64/gsubr.go

@@ -170,7 +170,7 @@ func bignodes() {
  */
 func gmove(f *gc.Node, t *gc.Node) {
 	if gc.Debug['M'] != 0 {
-		fmt.Printf("gmove %v -> %v\n", gc.Nconv(f, gc.FmtLong), gc.Nconv(t, gc.FmtLong))
+		fmt.Printf("gmove %2v -> %2v\n", f, t)
 	}
 
 	ft := int(gc.Simsimtype(f.Type))

src/cmd/compile/internal/s390x/ggen.go

@@ -42,7 +42,7 @@ func defframe(ptxt *obj.Prog) {
 			gc.Fatalf("needzero class %d", n.Class)
 		}
 		if n.Type.Width%int64(gc.Widthptr) != 0 || n.Xoffset%int64(gc.Widthptr) != 0 || n.Type.Width == 0 {
-			gc.Fatalf("var %v has size %d offset %d", gc.Nconv(n, gc.FmtLong), int(n.Type.Width), int(n.Xoffset))
+			gc.Fatalf("var %2v has size %d offset %d", n, int(n.Type.Width), int(n.Xoffset))
 		}
 
 		if lo != hi && n.Xoffset+n.Type.Width >= lo-int64(2*gc.Widthreg) {

src/cmd/compile/internal/s390x/gsubr.go

@@ -182,7 +182,7 @@ func gmvc(f, t *gc.Node) bool {
 // hard part is conversions.
 func gmove(f *gc.Node, t *gc.Node) {
 	if gc.Debug['M'] != 0 {
-		fmt.Printf("gmove %v -> %v\n", gc.Nconv(f, gc.FmtLong), gc.Nconv(t, gc.FmtLong))
+		fmt.Printf("gmove %2v -> %2v\n", f, t)
 	}
 
 	ft := int(gc.Simsimtype(f.Type))

src/cmd/compile/internal/x86/ggen.go

@@ -34,7 +34,7 @@ func defframe(ptxt *obj.Prog) {
 			gc.Fatalf("needzero class %d", n.Class)
 		}
 		if n.Type.Width%int64(gc.Widthptr) != 0 || n.Xoffset%int64(gc.Widthptr) != 0 || n.Type.Width == 0 {
-			gc.Fatalf("var %v has size %d offset %d", gc.Nconv(n, gc.FmtLong), int(n.Type.Width), int(n.Xoffset))
+			gc.Fatalf("var %2v has size %d offset %d", n, int(n.Type.Width), int(n.Xoffset))
 		}
 		if lo != hi && n.Xoffset+n.Type.Width == lo-int64(2*gc.Widthptr) {
 			// merge with range we already have

src/cmd/compile/internal/x86/gsubr.go

@@ -1594,7 +1594,7 @@ hardmem:
 
 	// should not happen
 fatal:
-	gc.Fatalf("gmove %v -> %v", gc.Nconv(f, gc.FmtLong), gc.Nconv(t, gc.FmtLong))
+	gc.Fatalf("gmove %2v -> %2v", f, t)
 
 	return
 }