cmd/compile: use Node.Right for OAS2* nodes (cleanup)

This CL changes cmd/compile to use Node.Right instead of
Node.Rlist for OAS2FUNC/OAS2RECV/OAS2MAPR/OAS2DOTTYPE nodes.
Fixes #32293

Change-Id: I4c9d9100be2d98d15e016797f934f64d385f5faa
Reviewed-on: https://go-review.googlesource.com/c/go/+/197817
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

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

@@ -361,18 +361,18 @@ func (e *Escape) stmt(n *Node) {
 		}
 
 	case OAS2DOTTYPE: // v, ok = x.(type)
-		e.assign(n.List.First(), n.Rlist.First(), "assign-pair-dot-type", n)
+		e.assign(n.List.First(), n.Right, "assign-pair-dot-type", n)
 		e.assign(n.List.Second(), nil, "assign-pair-dot-type", n)
 	case OAS2MAPR: // v, ok = m[k]
-		e.assign(n.List.First(), n.Rlist.First(), "assign-pair-mapr", n)
+		e.assign(n.List.First(), n.Right, "assign-pair-mapr", n)
 		e.assign(n.List.Second(), nil, "assign-pair-mapr", n)
 	case OAS2RECV: // v, ok = <-ch
-		e.assign(n.List.First(), n.Rlist.First(), "assign-pair-receive", n)
+		e.assign(n.List.First(), n.Right, "assign-pair-receive", n)
 		e.assign(n.List.Second(), nil, "assign-pair-receive", n)
 
 	case OAS2FUNC:
-		e.stmts(n.Rlist.First().Ninit)
-		e.call(e.addrs(n.List), n.Rlist.First(), nil)
+		e.stmts(n.Right.Ninit)
+		e.call(e.addrs(n.List), n.Right, nil)
 	case ORETURN:
 		results := e.curfn.Type.Results().FieldSlice()
 		for i, v := range n.List.Slice() {

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

@@ -945,8 +945,7 @@ func (n *Node) stmtfmt(s fmt.State, mode fmtMode) {
 		fallthrough
 
 	case OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV:
-		mode.Fprintf(s, "%.v = %.v", n.List, n.Rlist)
-
+		mode.Fprintf(s, "%.v = %.v", n.List, n.Right)
 	case ORETURN:
 		mode.Fprintf(s, "return %.v", n.List)
 

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

@@ -1044,12 +1044,18 @@ func (w *exportWriter) stmt(n *Node) {
 			w.expr(n.Right)
 		}
 
-	case OAS2, OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV:
+	case OAS2:
 		w.op(OAS2)
 		w.pos(n.Pos)
 		w.exprList(n.List)
 		w.exprList(n.Rlist)
 
+	case OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV:
+		w.op(OAS2)
+		w.pos(n.Pos)
+		w.exprList(n.List)
+		w.exprList(asNodes([]*Node{n.Right}))
+
 	case ORETURN:
 		w.op(ORETURN)
 		w.pos(n.Pos)

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

@@ -254,7 +254,7 @@ func collectDeps(n *Node, transitive bool) NodeSet {
 	case OAS:
 		d.inspect(n.Right)
 	case OAS2DOTTYPE, OAS2FUNC, OAS2MAPR, OAS2RECV:
-		d.inspect(n.Rlist.First())
+		d.inspect(n.Right)
 	case ODCLFUNC:
 		d.inspectList(n.Nbody)
 	default:

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

@@ -580,6 +580,12 @@ func inlnode(n *Node, maxCost int32) *Node {
 	if n.Right != nil && n.Right.Op == OINLCALL {
 		if n.Op == OFOR || n.Op == OFORUNTIL {
 			inlconv2stmt(n.Right)
+		} else if n.Op == OAS2FUNC {
+			n.Rlist.Set(inlconv2list(n.Right))
+			n.Right = nil
+			n.Op = OAS2
+			n.SetTypecheck(0)
+			n = typecheck(n, ctxStmt)
 		} else {
 			n.Right = inlconv2expr(n.Right)
 		}
@@ -602,20 +608,13 @@ func inlnode(n *Node, maxCost int32) *Node {
 	}
 
 	inlnodelist(n.Rlist, maxCost)
-	if n.Op == OAS2FUNC && n.Rlist.First().Op == OINLCALL {
-		n.Rlist.Set(inlconv2list(n.Rlist.First()))
-		n.Op = OAS2
-		n.SetTypecheck(0)
-		n = typecheck(n, ctxStmt)
-	} else {
-		s := n.Rlist.Slice()
-		for i1, n1 := range s {
-			if n1.Op == OINLCALL {
-				if n.Op == OIF {
-					inlconv2stmt(n1)
-				} else {
-					s[i1] = inlconv2expr(s[i1])
-				}
+	s := n.Rlist.Slice()
+	for i1, n1 := range s {
+		if n1.Op == OINLCALL {
+			if n.Op == OIF {
+				inlconv2stmt(n1)
+			} else {
+				s[i1] = inlconv2expr(s[i1])
 			}
 		}
 	}

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

@@ -567,7 +567,7 @@ func (o *Order) stmt(n *Node) {
 	case OAS2MAPR:
 		t := o.markTemp()
 		o.exprList(n.List)
-		r := n.Rlist.First()
+		r := n.Right
 		r.Left = o.expr(r.Left, nil)
 		r.Right = o.expr(r.Right, nil)
 
@@ -582,8 +582,8 @@ func (o *Order) stmt(n *Node) {
 	case OAS2FUNC:
 		t := o.markTemp()
 		o.exprList(n.List)
-		o.init(n.Rlist.First())
-		o.call(n.Rlist.First())
+		o.init(n.Right)
+		o.call(n.Right)
 		o.as2(n)
 		o.cleanTemp(t)
 
@@ -593,7 +593,7 @@ func (o *Order) stmt(n *Node) {
 	case OAS2DOTTYPE:
 		t := o.markTemp()
 		o.exprList(n.List)
-		n.Rlist.First().Left = o.expr(n.Rlist.First().Left, nil) // i in i.(T)
+		n.Right.Left = o.expr(n.Right.Left, nil) // i in i.(T)
 		o.okAs2(n)
 		o.cleanTemp(t)
 
@@ -602,8 +602,8 @@ func (o *Order) stmt(n *Node) {
 	case OAS2RECV:
 		t := o.markTemp()
 		o.exprList(n.List)
-		n.Rlist.First().Left = o.expr(n.Rlist.First().Left, nil) // arg to recv
-		ch := n.Rlist.First().Left.Type
+		n.Right.Left = o.expr(n.Right.Left, nil) // arg to recv
+		ch := n.Right.Left.Type
 		tmp1 := o.newTemp(ch.Elem(), types.Haspointers(ch.Elem()))
 		tmp2 := o.newTemp(types.Types[TBOOL], false)
 		o.out = append(o.out, n)
@@ -1343,7 +1343,7 @@ func (o *Order) as2(n *Node) {
 func (o *Order) okAs2(n *Node) {
 	var tmp1, tmp2 *Node
 	if !n.List.First().isBlank() {
-		typ := n.Rlist.First().Type
+		typ := n.Right.Type
 		tmp1 = o.newTemp(typ, types.Haspointers(typ))
 	}
 

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

@@ -343,7 +343,7 @@ func walkrange(n *Node) *Node {
 		a := nod(OAS2RECV, nil, nil)
 		a.SetTypecheck(1)
 		a.List.Set2(hv1, hb)
-		a.Rlist.Set1(nod(ORECV, ha, nil))
+		a.Right = nod(ORECV, ha, nil)
 		n.Left.Ninit.Set1(a)
 		if v1 == nil {
 			body = nil

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

@@ -60,7 +60,7 @@ func typecheckselect(sel *Node) {
 
 				// convert x, ok = <-c into OSELRECV2(x, <-c) with ntest=ok
 			case OAS2RECV:
-				if n.Rlist.First().Op != ORECV {
+				if n.Right.Op != ORECV {
 					yyerrorl(n.Pos, "select assignment must have receive on right hand side")
 					break
 				}
@@ -68,8 +68,6 @@ func typecheckselect(sel *Node) {
 				n.Op = OSELRECV2
 				n.Left = n.List.First()
 				n.List.Set1(n.List.Second())
-				n.Right = n.Rlist.First()
-				n.Rlist.Set(nil)
 
 				// convert <-c into OSELRECV(N, <-c)
 			case ORECV:

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

@@ -874,9 +874,9 @@ func (s *state) stmt(n *Node) {
 		s.call(n.Left, callGo)
 
 	case OAS2DOTTYPE:
-		res, resok := s.dottype(n.Rlist.First(), true)
+		res, resok := s.dottype(n.Right, true)
 		deref := false
-		if !canSSAType(n.Rlist.First().Type) {
+		if !canSSAType(n.Right.Type) {
 			if res.Op != ssa.OpLoad {
 				s.Fatalf("dottype of non-load")
 			}
@@ -896,10 +896,10 @@ func (s *state) stmt(n *Node) {
 
 	case OAS2FUNC:
 		// We come here only when it is an intrinsic call returning two values.
-		if !isIntrinsicCall(n.Rlist.First()) {
-			s.Fatalf("non-intrinsic AS2FUNC not expanded %v", n.Rlist.First())
+		if !isIntrinsicCall(n.Right) {
+			s.Fatalf("non-intrinsic AS2FUNC not expanded %v", n.Right)
 		}
-		v := s.intrinsicCall(n.Rlist.First())
+		v := s.intrinsicCall(n.Right)
 		v1 := s.newValue1(ssa.OpSelect0, n.List.First().Type, v)
 		v2 := s.newValue1(ssa.OpSelect1, n.List.Second().Type, v)
 		s.assign(n.List.First(), v1, false, 0)

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

@@ -600,10 +600,10 @@ const (
 	OSTR2RUNES    // Type(Left) (Type is []rune, Left is a string)
 	OAS           // Left = Right or (if Colas=true) Left := Right
 	OAS2          // List = Rlist (x, y, z = a, b, c)
-	OAS2DOTTYPE   // List = Rlist (x, ok = I.(int))
-	OAS2FUNC      // List = Rlist (x, y = f())
-	OAS2MAPR      // List = Rlist (x, ok = m["foo"])
-	OAS2RECV      // List = Rlist (x, ok = <-c)
+	OAS2DOTTYPE   // List = Right (x, ok = I.(int))
+	OAS2FUNC      // List = Right (x, y = f())
+	OAS2MAPR      // List = Right (x, ok = m["foo"])
+	OAS2RECV      // List = Right (x, ok = <-c)
 	OASOP         // Left Etype= Right (x += y)
 	OCALL         // Left(List) (function call, method call or type conversion)
 

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

@@ -3275,6 +3275,8 @@ func typecheckas2(n *Node) {
 				goto mismatch
 			}
 			n.Op = OAS2FUNC
+			n.Right = r
+			n.Rlist.Set(nil)
 			for i, l := range n.List.Slice() {
 				f := r.Type.Field(i)
 				if f.Type != nil && l.Type != nil {
@@ -3298,15 +3300,14 @@ func typecheckas2(n *Node) {
 			switch r.Op {
 			case OINDEXMAP:
 				n.Op = OAS2MAPR
-
 			case ORECV:
 				n.Op = OAS2RECV
-
 			case ODOTTYPE:
 				n.Op = OAS2DOTTYPE
 				r.Op = ODOTTYPE2
 			}
-
+			n.Right = r
+			n.Rlist.Set(nil)
 			if l.Type != nil {
 				checkassignto(r.Type, l)
 			}

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

@@ -691,12 +691,12 @@ opswitch:
 	case OAS2FUNC:
 		init.AppendNodes(&n.Ninit)
 
-		r := n.Rlist.First()
+		r := n.Right
 		walkexprlistsafe(n.List.Slice(), init)
 		r = walkexpr(r, init)
 
 		if isIntrinsicCall(r) {
-			n.Rlist.Set1(r)
+			n.Right = r
 			break
 		}
 		init.Append(r)
@@ -709,7 +709,7 @@ opswitch:
 	case OAS2RECV:
 		init.AppendNodes(&n.Ninit)
 
-		r := n.Rlist.First()
+		r := n.Right
 		walkexprlistsafe(n.List.Slice(), init)
 		r.Left = walkexpr(r.Left, init)
 		var n1 *Node
@@ -728,7 +728,7 @@ opswitch:
 	case OAS2MAPR:
 		init.AppendNodes(&n.Ninit)
 
-		r := n.Rlist.First()
+		r := n.Right
 		walkexprlistsafe(n.List.Slice(), init)
 		r.Left = walkexpr(r.Left, init)
 		r.Right = walkexpr(r.Right, init)
@@ -767,7 +767,7 @@ opswitch:
 		if ok := n.List.Second(); !ok.isBlank() && ok.Type.IsBoolean() {
 			r.Type.Field(1).Type = ok.Type
 		}
-		n.Rlist.Set1(r)
+		n.Right = r
 		n.Op = OAS2FUNC
 
 		// don't generate a = *var if a is _
@@ -801,7 +801,7 @@ opswitch:
 
 	case OAS2DOTTYPE:
 		walkexprlistsafe(n.List.Slice(), init)
-		n.Rlist.SetFirst(walkexpr(n.Rlist.First(), init))
+		n.Right = walkexpr(n.Right, init)
 
 	case OCONVIFACE:
 		n.Left = walkexpr(n.Left, init)