cmd/compile: change export.go and fmt.go to use nodeSeq

Also fix some uses of nodeSeqIterator.Len, and fix the implementation in
nodesIterator.

Passes toolstash -cmp.

Update #14473.

Change-Id: I228871470234b7f1314ffd2aae8a4c0624c35f98
Reviewed-on: https://go-review.googlesource.com/20231
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

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

@@ -296,7 +296,7 @@ func genhash(sym *Sym, t *Type) {
 	fn.Nbody.Append(r)
 
 	if Debug['r'] != 0 {
-		dumpslice("genhash body", fn.Nbody.Slice())
+		dumplist("genhash body", fn.Nbody)
 	}
 
 	funcbody(fn)
@@ -504,7 +504,7 @@ func geneq(sym *Sym, t *Type) {
 	}
 
 	if Debug['r'] != 0 {
-		dumpslice("geneq body", fn.Nbody.Slice())
+		dumplist("geneq body", fn.Nbody)
 	}
 
 	funcbody(fn)

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

@@ -333,7 +333,7 @@ func Export(out *obj.Biobuf, trace bool) int {
 	}
 	for _, f := range p.inlined {
 		if p.trace {
-			p.tracef("{ %s }\n", Hconvslice(f.Inl.Slice(), obj.FmtSharp))
+			p.tracef("{ %s }\n", Hconv(f.Inl, obj.FmtSharp))
 		}
 		p.nodeList(f.Inl)
 		if p.trace {
@@ -813,7 +813,7 @@ func (p *exporter) nodeList(list nodesOrNodeList) {
 	}
 	p.int(it.Len())
 	if p.trace {
-		if it.Len() == 0 {
+		if it.Len() <= 1 {
 			p.tracef("] {}")
 		} else {
 			p.tracef("] {>")

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

@@ -106,15 +106,9 @@ func dumppkg(p *Pkg) {
 }
 
 // Look for anything we need for the inline body
-func reexportdeplist(ll *NodeList) {
+func reexportdeplist(ll nodesOrNodeList) {
-	for ; ll != nil; ll = ll.Next {
+	for it := nodeSeqIterate(ll); !it.Done(); it.Next() {
-		reexportdep(ll.N)
+		reexportdep(it.N())
-	}
-}
-
-func reexportdepslice(ll []*Node) {
-	for _, n := range ll {
-		reexportdep(n)
 	}
 }
 
@@ -223,7 +217,7 @@ func reexportdep(n *Node) {
 	reexportdeplist(n.List)
 	reexportdeplist(n.Rlist)
 	reexportdeplist(n.Ninit)
-	reexportdepslice(n.Nbody.Slice())
+	reexportdeplist(n.Nbody)
 }
 
 func dumpexportconst(s *Sym) {
@@ -263,9 +257,9 @@ func dumpexportvar(s *Sym) {
 			}
 
 			// NOTE: The space after %#S here is necessary for ld's export data parser.
-			exportf("\tfunc %v %v { %v }\n", Sconv(s, obj.FmtSharp), Tconv(t, obj.FmtShort|obj.FmtSharp), Hconvslice(n.Func.Inl.Slice(), obj.FmtSharp|obj.FmtBody))
+			exportf("\tfunc %v %v { %v }\n", Sconv(s, obj.FmtSharp), Tconv(t, obj.FmtShort|obj.FmtSharp), Hconv(n.Func.Inl, obj.FmtSharp|obj.FmtBody))
 
-			reexportdepslice(n.Func.Inl.Slice())
+			reexportdeplist(n.Func.Inl)
 		} else {
 			exportf("\tfunc %v %v\n", Sconv(s, obj.FmtSharp), Tconv(t, obj.FmtShort|obj.FmtSharp))
 		}
@@ -320,8 +314,8 @@ func dumpexporttype(t *Type) {
 			if Debug['l'] < 2 {
 				typecheckinl(f.Type.Nname)
 			}
-			exportf("\tfunc (%v) %v %v { %v }\n", Tconv(getthisx(f.Type).Type, obj.FmtSharp), Sconv(f.Sym, obj.FmtShort|obj.FmtByte|obj.FmtSharp), Tconv(f.Type, obj.FmtShort|obj.FmtSharp), Hconvslice(f.Type.Nname.Func.Inl.Slice(), obj.FmtSharp))
+			exportf("\tfunc (%v) %v %v { %v }\n", Tconv(getthisx(f.Type).Type, obj.FmtSharp), Sconv(f.Sym, obj.FmtShort|obj.FmtByte|obj.FmtSharp), Tconv(f.Type, obj.FmtShort|obj.FmtSharp), Hconv(f.Type.Nname.Func.Inl, obj.FmtSharp))
-			reexportdepslice(f.Type.Nname.Func.Inl.Slice())
+			reexportdeplist(f.Type.Nname.Func.Inl)
 		} else {
 			exportf("\tfunc (%v) %v %v\n", Tconv(getthisx(f.Type).Type, obj.FmtSharp), Sconv(f.Sym, obj.FmtShort|obj.FmtByte|obj.FmtSharp), Tconv(f.Type, obj.FmtShort|obj.FmtSharp))
 		}

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

@@ -800,10 +800,10 @@ func stmtfmt(n *Node) string {
 	// block starting with the init statements.
 
 	// if we can just say "for" n->ninit; ... then do so
-	simpleinit := n.Ninit != nil && n.Ninit.Next == nil && n.Ninit.N.Ninit == nil && stmtwithinit(n.Op)
+	simpleinit := nodeSeqLen(n.Ninit) == 1 && nodeSeqLen(nodeSeqFirst(n.Ninit).Ninit) == 0 && stmtwithinit(n.Op)
 
 	// otherwise, print the inits as separate statements
-	complexinit := n.Ninit != nil && !simpleinit && (fmtmode != FErr)
+	complexinit := nodeSeqLen(n.Ninit) != 0 && !simpleinit && (fmtmode != FErr)
 
 	// but if it was for if/for/switch, put in an extra surrounding block to limit the scope
 	extrablock := complexinit && stmtwithinit(n.Op)
@@ -889,7 +889,7 @@ func stmtfmt(n *Node) string {
 		} else {
 			f += fmt.Sprintf("if %v { %v }", n.Left, n.Nbody)
 		}
-		if n.Rlist != nil {
+		if nodeSeqLen(n.Rlist) != 0 {
 			f += fmt.Sprintf(" else { %v }", n.Rlist)
 		}
 
@@ -901,7 +901,7 @@ func stmtfmt(n *Node) string {
 
 		f += "for"
 		if simpleinit {
-			f += fmt.Sprintf(" %v;", n.Ninit.N)
+			f += fmt.Sprintf(" %v;", nodeSeqFirst(n.Ninit))
 		} else if n.Right != nil {
 			f += " ;"
 		}
@@ -924,7 +924,7 @@ func stmtfmt(n *Node) string {
 			break
 		}
 
-		if n.List == nil {
+		if nodeSeqLen(n.List) == 0 {
 			f += fmt.Sprintf("for range %v { %v }", n.Right, n.Nbody)
 			break
 		}
@@ -939,7 +939,7 @@ func stmtfmt(n *Node) string {
 
 		f += Oconv(int(n.Op), obj.FmtSharp)
 		if simpleinit {
-			f += fmt.Sprintf(" %v;", n.Ninit.N)
+			f += fmt.Sprintf(" %v;", nodeSeqFirst(n.Ninit))
 		}
 		if n.Left != nil {
 			f += Nconv(n.Left, 0)
@@ -948,7 +948,7 @@ func stmtfmt(n *Node) string {
 		f += fmt.Sprintf(" { %v }", n.List)
 
 	case OCASE, OXCASE:
-		if n.List != nil {
+		if nodeSeqLen(n.List) != 0 {
 			f += fmt.Sprintf("case %v: %v", Hconv(n.List, obj.FmtComma), n.Nbody)
 		} else {
 			f += fmt.Sprintf("default: %v", n.Nbody)
@@ -1257,10 +1257,10 @@ func exprfmt(n *Node, prec int) string {
 			} else {
 				f += fmt.Sprintf("(%v{", n.Type)
 			}
-			for l := n.List; l != nil; l = l.Next {
+			for it := nodeSeqIterate(n.List); !it.Done(); it.Next() {
-				f += fmt.Sprintf(" %v:%v", Sconv(l.N.Left.Sym, obj.FmtShort|obj.FmtByte), l.N.Right)
+				f += fmt.Sprintf(" %v:%v", Sconv(it.N().Left.Sym, obj.FmtShort|obj.FmtByte), it.N().Right)
 
-				if l.Next != nil {
+				if it.Len() > 1 {
 					f += ","
 				} else {
 					f += " "
@@ -1391,7 +1391,7 @@ func exprfmt(n *Node, prec int) string {
 		return f
 
 	case OMAKEMAP, OMAKECHAN, OMAKESLICE:
-		if n.List != nil { // pre-typecheck
+		if nodeSeqLen(n.List) != 0 { // pre-typecheck
 			return fmt.Sprintf("make(%v, %v)", n.Type, Hconv(n.List, obj.FmtComma))
 		}
 		if n.Right != nil {
@@ -1449,11 +1449,13 @@ func exprfmt(n *Node, prec int) string {
 
 	case OADDSTR:
 		var f string
-		for l := n.List; l != nil; l = l.Next {
+		i := 0
-			if l != n.List {
+		for it := nodeSeqIterate(n.List); !it.Done(); it.Next() {
+			if i != 0 {
 				f += " + "
 			}
-			f += exprfmt(l.N, nprec)
+			f += exprfmt(it.N(), nprec)
+			i++
 		}
 
 		return f
@@ -1521,7 +1523,7 @@ func nodedump(n *Node, flag int) string {
 			return buf.String()
 		}
 
-		if n.Ninit != nil {
+		if nodeSeqLen(n.Ninit) != 0 {
 			fmt.Fprintf(&buf, "%v-init%v", Oconv(int(n.Op), 0), n.Ninit)
 			indent(&buf)
 		}
@@ -1574,12 +1576,12 @@ func nodedump(n *Node, flag int) string {
 		if n.Right != nil {
 			buf.WriteString(Nconv(n.Right, 0))
 		}
-		if n.List != nil {
+		if nodeSeqLen(n.List) != 0 {
 			indent(&buf)
 			fmt.Fprintf(&buf, "%v-list%v", Oconv(int(n.Op), 0), n.List)
 		}
 
-		if n.Rlist != nil {
+		if nodeSeqLen(n.Rlist) != 0 {
 			indent(&buf)
 			fmt.Fprintf(&buf, "%v-rlist%v", Oconv(int(n.Op), 0), n.Rlist)
 		}
@@ -1701,13 +1703,13 @@ func (l *NodeList) String() string {
 }
 
 func (n Nodes) String() string {
-	return Hconvslice(n.Slice(), 0)
+	return Hconv(n, 0)
 }
 
 // Fmt '%H': NodeList.
 // Flags: all those of %N plus ',': separate with comma's instead of semicolons.
-func Hconv(l *NodeList, flag int) string {
+func Hconv(l nodesOrNodeList, flag int) string {
-	if l == nil && fmtmode == FDbg {
+	if nodeSeqLen(l) == 0 && fmtmode == FDbg {
 		return "<nil>"
 	}
 
@@ -1721,9 +1723,9 @@ func Hconv(l *NodeList, flag int) string {
 	}
 
 	var buf bytes.Buffer
-	for ; l != nil; l = l.Next {
+	for it := nodeSeqIterate(l); !it.Done(); it.Next() {
-		buf.WriteString(Nconv(l.N, 0))
+		buf.WriteString(Nconv(it.N(), 0))
-		if l.Next != nil {
+		if it.Len() > 1 {
 			buf.WriteString(sep)
 		}
 	}
@@ -1734,42 +1736,10 @@ func Hconv(l *NodeList, flag int) string {
 	return buf.String()
 }
 
-func Hconvslice(l []*Node, flag int) string {
+func dumplist(s string, l nodesOrNodeList) {
-	if len(l) == 0 && fmtmode == FDbg {
-		return "<nil>"
-	}
-
-	sf := flag
-	sm, sb := setfmode(&flag)
-	sep := "; "
-	if fmtmode == FDbg {
-		sep = "\n"
-	} else if flag&obj.FmtComma != 0 {
-		sep = ", "
-	}
-
-	var buf bytes.Buffer
-	for i, n := range l {
-		buf.WriteString(Nconv(n, 0))
-		if i+1 < len(l) {
-			buf.WriteString(sep)
-		}
-	}
-
-	flag = sf
-	fmtbody = sb
-	fmtmode = sm
-	return buf.String()
-}
-
-func dumplist(s string, l *NodeList) {
 	fmt.Printf("%s%v\n", s, Hconv(l, obj.FmtSign))
 }
 
-func dumpslice(s string, l []*Node) {
-	fmt.Printf("%s%v\n", s, Hconvslice(l, obj.FmtSign))
-}
-
 func Dump(s string, n *Node) {
 	fmt.Printf("%s [%p]%v\n", s, n, Nconv(n, obj.FmtSign))
 }

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

@@ -79,7 +79,7 @@ func typecheckinl(fn *Node) {
 	}
 
 	if Debug['m'] > 2 {
-		fmt.Printf("typecheck import [%v] %v { %v }\n", fn.Sym, Nconv(fn, obj.FmtLong), Hconvslice(fn.Func.Inl.Slice(), obj.FmtSharp))
+		fmt.Printf("typecheck import [%v] %v { %v }\n", fn.Sym, Nconv(fn, obj.FmtLong), Hconv(fn.Func.Inl, obj.FmtSharp))
 	}
 
 	save_safemode := safemode
@@ -161,7 +161,7 @@ func caninl(fn *Node) {
 	fn.Type.Nname = fn.Func.Nname
 
 	if Debug['m'] > 1 {
-		fmt.Printf("%v: can inline %v as: %v { %v }\n", fn.Line(), Nconv(fn.Func.Nname, obj.FmtSharp), Tconv(fn.Type, obj.FmtSharp), Hconvslice(fn.Func.Nname.Func.Inl.Slice(), obj.FmtSharp))
+		fmt.Printf("%v: can inline %v as: %v { %v }\n", fn.Line(), Nconv(fn.Func.Nname, obj.FmtSharp), Tconv(fn.Type, obj.FmtSharp), Hconv(fn.Func.Nname.Func.Inl, obj.FmtSharp))
 	} else if Debug['m'] != 0 {
 		fmt.Printf("%v: can inline %v\n", fn.Line(), fn.Func.Nname)
 	}
@@ -543,7 +543,7 @@ func mkinlcall1(np **Node, fn *Node, isddd bool) {
 
 	// Bingo, we have a function node, and it has an inlineable body
 	if Debug['m'] > 1 {
-		fmt.Printf("%v: inlining call to %v %v { %v }\n", n.Line(), fn.Sym, Tconv(fn.Type, obj.FmtSharp), Hconvslice(fn.Func.Inl.Slice(), obj.FmtSharp))
+		fmt.Printf("%v: inlining call to %v %v { %v }\n", n.Line(), fn.Sym, Tconv(fn.Type, obj.FmtSharp), Hconv(fn.Func.Inl, obj.FmtSharp))
 	} else if Debug['m'] != 0 {
 		fmt.Printf("%v: inlining call to %v\n", n.Line(), fn)
 	}

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

@@ -50,7 +50,7 @@ type Order struct {
 func order(fn *Node) {
 	if Debug['W'] > 1 {
 		s := fmt.Sprintf("\nbefore order %v", fn.Func.Nname.Sym)
-		dumpslice(s, fn.Nbody.Slice())
+		dumplist(s, fn.Nbody)
 	}
 
 	orderblockNodes(&fn.Nbody)

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

@@ -78,11 +78,11 @@ func instrument(fn *Node) {
 
 	if Debug['W'] != 0 {
 		s := fmt.Sprintf("after instrument %v", fn.Func.Nname.Sym)
-		dumpslice(s, fn.Nbody.Slice())
+		dumplist(s, fn.Nbody)
 		s = fmt.Sprintf("enter %v", fn.Func.Nname.Sym)
-		dumpslice(s, fn.Func.Enter.Slice())
+		dumplist(s, fn.Func.Enter)
 		s = fmt.Sprintf("exit %v", fn.Func.Nname.Sym)
-		dumpslice(s, fn.Func.Exit.Slice())
+		dumplist(s, fn.Func.Exit)
 	}
 }
 

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

@@ -89,9 +89,9 @@ func buildssa(fn *Node) *ssa.Func {
 	printssa := name == os.Getenv("GOSSAFUNC")
 	if printssa {
 		fmt.Println("generating SSA for", name)
-		dumpslice("buildssa-enter", fn.Func.Enter.Slice())
+		dumplist("buildssa-enter", fn.Func.Enter)
-		dumpslice("buildssa-body", fn.Nbody.Slice())
+		dumplist("buildssa-body", fn.Nbody)
-		dumpslice("buildssa-exit", fn.Func.Exit.Slice())
+		dumplist("buildssa-exit", fn.Func.Exit)
 	}
 
 	var s state

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

@@ -2185,7 +2185,7 @@ func genwrapper(rcvr *Type, method *Type, newnam *Sym, iface int) {
 	}
 
 	if false && Debug['r'] != 0 {
-		dumpslice("genwrapper body", fn.Nbody.Slice())
+		dumplist("genwrapper body", fn.Nbody)
 	}
 
 	funcbody(fn)

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

@@ -578,7 +578,7 @@ func (ni *nodesIterator) P() **Node {
 }
 
 func (ni *nodesIterator) Len() int {
-	return len(ni.n.Slice())
+	return len(ni.n.Slice()[ni.i:])
 }
 
 func (ni *nodesIterator) Seq() nodesOrNodeList {

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

@@ -22,7 +22,7 @@ func walk(fn *Node) {
 
 	if Debug['W'] != 0 {
 		s := fmt.Sprintf("\nbefore %v", Curfn.Func.Nname.Sym)
-		dumpslice(s, Curfn.Nbody.Slice())
+		dumplist(s, Curfn.Nbody)
 	}
 
 	lno := lineno
@@ -67,13 +67,13 @@ func walk(fn *Node) {
 	walkstmtlist(Curfn.Nbody)
 	if Debug['W'] != 0 {
 		s := fmt.Sprintf("after walk %v", Curfn.Func.Nname.Sym)
-		dumpslice(s, Curfn.Nbody.Slice())
+		dumplist(s, Curfn.Nbody)
 	}
 
 	heapmoves()
 	if Debug['W'] != 0 && len(Curfn.Func.Enter.Slice()) > 0 {
 		s := fmt.Sprintf("enter %v", Curfn.Func.Nname.Sym)
-		dumpslice(s, Curfn.Func.Enter.Slice())
+		dumplist(s, Curfn.Func.Enter)
 	}
 }
 
@@ -2963,7 +2963,7 @@ func walkappend(n *Node, init nodesOrNodeListPtr, dst *Node) *Node {
 		nx = Nod(OINDEX, ns, nn) // s[n] ...
 		nx.Bounded = true
 		l = append(l, Nod(OAS, nx, it.N())) // s[n] = arg
-		if it.Len() != 0 {
+		if it.Len() > 1 {
 			l = append(l, Nod(OAS, nn, Nod(OADD, nn, Nodintconst(1)))) // n = n + 1
 		}
 	}