cmd/compile: encapsulate Type.Nname

Generated by eg, manually fixed up.

I’m not thrilled about having a setter,
but given the variety of contexts in which this
gets fiddled with, it is the cleanest
available alternative.

Change-Id: Ibdf23e638fe0bdabded014c9e59d557fab8c955f
Reviewed-on: https://go-review.googlesource.com/21341
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

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

@@ -481,14 +481,14 @@ func (p *exporter) typ(t *Type) {
 			}
 			p.string(m.Sym.Name)
 			sig := m.Type
-			inlineable := p.isInlineable(sig.Nname)
+			inlineable := p.isInlineable(sig.Nname())
 			p.paramList(sig.Recvs(), inlineable)
 			p.paramList(sig.Params(), inlineable)
 			p.paramList(sig.Results(), inlineable)
 			index := -1
 			if inlineable {
 				index = len(p.inlined)
-				p.inlined = append(p.inlined, sig.Nname.Func)
+				p.inlined = append(p.inlined, sig.Nname().Func)
 			}
 			p.int(index)
 		}

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

@@ -261,7 +261,7 @@ func (p *importer) typ() *Type {
 			// (dotmeth's type).Nname.Inl, and dotmeth's type has been pulled
 			// out by typecheck's lookdot as this $$.ttype. So by providing
 			// this back link here we avoid special casing there.
-			n.Type.Nname = n
+			n.Type.SetNname(n)
 
 			// parser.go:hidden_import
 			n.Func.Inl.Set(nil)

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

@@ -875,8 +875,7 @@ func interfacefield(n *Node) *Field {
 			// right now all we need is the name list.
 			// avoids cycles for recursive interface types.
 			n.Type = typ(TINTERMETH)
-
+			n.Type.SetNname(n.Right)
-			n.Type.Nname = n.Right
 			n.Left.Type = n.Type
 			queuemethod(n)
 

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

@@ -323,15 +323,15 @@ func dumpexporttype(t *Type) {
 		if f.Nointerface {
 			exportf("\t//go:nointerface\n")
 		}
-		if f.Type.Nname != nil && len(f.Type.Nname.Func.Inl.Slice()) != 0 { // nname was set by caninl
+		if f.Type.Nname() != nil && len(f.Type.Nname().Func.Inl.Slice()) != 0 { // nname was set by caninl
 
 			// when lazily typechecking inlined bodies, some re-exported ones may not have been typechecked yet.
 			// currently that can leave unresolved ONONAMEs in import-dot-ed packages in the wrong package
 			if Debug['l'] < 2 {
-				typecheckinl(f.Type.Nname)
+				typecheckinl(f.Type.Nname())
 			}
-			exportf("\tfunc %v %v %v { %v }\n", Tconv(f.Type.Recvs(), FmtSharp), Sconv(f.Sym, FmtShort|FmtByte|FmtSharp), Tconv(f.Type, FmtShort|FmtSharp), Hconv(f.Type.Nname.Func.Inl, FmtSharp|FmtBody))
+			exportf("\tfunc %v %v %v { %v }\n", Tconv(f.Type.Recvs(), FmtSharp), Sconv(f.Sym, FmtShort|FmtByte|FmtSharp), Tconv(f.Type, FmtShort|FmtSharp), Hconv(f.Type.Nname().Func.Inl, FmtSharp|FmtBody))
-			reexportdeplist(f.Type.Nname.Func.Inl)
+			reexportdeplist(f.Type.Nname().Func.Inl)
 		} else {
 			exportf("\tfunc %v %v %v\n", Tconv(f.Type.Recvs(), FmtSharp), Sconv(f.Sym, FmtShort|FmtByte|FmtSharp), Tconv(f.Type, FmtShort|FmtSharp))
 		}

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

@@ -144,7 +144,7 @@ func caninl(fn *Node) {
 
 	// hack, TODO, check for better way to link method nodes back to the thing with the ->inl
 	// this is so export can find the body of a method
-	fn.Type.Nname = fn.Func.Nname
+	fn.Type.SetNname(fn.Func.Nname)
 
 	if Debug['m'] > 1 {
 		fmt.Printf("%v: can inline %v as: %v { %v }\n", fn.Line(), Nconv(fn.Func.Nname, FmtSharp), Tconv(fn.Type, FmtSharp), Hconv(fn.Func.Nname.Func.Inl, FmtSharp))
@@ -192,11 +192,11 @@ func ishairy(n *Node, budget *int) bool {
 		if n.Left.Type == nil {
 			Fatalf("no function type for [%p] %v\n", n.Left, Nconv(n.Left, FmtSign))
 		}
-		if n.Left.Type.Nname == nil {
+		if n.Left.Type.Nname() == nil {
 			Fatalf("no function definition for [%p] %v\n", n.Left.Type, Tconv(n.Left.Type, FmtSign))
 		}
-		if len(n.Left.Type.Nname.Func.Inl.Slice()) != 0 {
+		if len(n.Left.Type.Nname().Func.Inl.Slice()) != 0 {
-			*budget -= int(n.Left.Type.Nname.Func.InlCost)
+			*budget -= int(n.Left.Type.Nname().Func.InlCost)
 			break
 		}
 		if Debug['l'] < 4 {
@@ -471,11 +471,11 @@ func inlnode(n *Node) *Node {
 			Fatalf("no function type for [%p] %v\n", n.Left, Nconv(n.Left, FmtSign))
 		}
 
-		if n.Left.Type.Nname == nil {
+		if n.Left.Type.Nname() == nil {
 			Fatalf("no function definition for [%p] %v\n", n.Left.Type, Tconv(n.Left.Type, FmtSign))
 		}
 
-		n = mkinlcall(n, n.Left.Type.Nname, n.Isddd)
+		n = mkinlcall(n, n.Left.Type.Nname(), n.Isddd)
 	}
 
 	lineno = lno

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

@@ -2018,7 +2018,7 @@ func (p *parser) hidden_fndcl() *Node {
 		// (dotmeth's type).Nname.Inl, and dotmeth's type has been pulled
 		// out by typecheck's lookdot as this $$.ttype. So by providing
 		// this back link here we avoid special casing there.
-		ss.Type.Nname = ss
+		ss.Type.SetNname(ss)
 		return ss
 	}
 }

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

@@ -255,9 +255,9 @@ func methodfunc(f *Type, receiver *Type) *Type {
 	}
 
 	t := functype(nil, in, out)
-	if f.Nname != nil {
+	if f.Nname() != nil {
 		// Link to name of original method function.
-		t.Nname = f.Nname
+		t.SetNname(f.Nname())
 	}
 
 	return t

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

@@ -45,7 +45,7 @@ func init1(n *Node, out *[]*Node) {
 	if n.Left != nil && n.Type != nil && n.Left.Op == OTYPE && n.Class == PFUNC {
 		// Methods called as Type.Method(receiver, ...).
 		// Definitions for method expressions are stored in type->nname.
-		init1(n.Type.Nname, out)
+		init1(n.Type.Nname(), out)
 	}
 
 	if n.Op != ONAME {
@@ -216,7 +216,7 @@ func init2(n *Node, out *[]*Node) {
 		init2list(n.Func.Closure.Nbody, out)
 	}
 	if n.Op == ODOTMETH || n.Op == OCALLPART {
-		init2(n.Type.Nname, out)
+		init2(n.Type.Nname(), out)
 	}
 }
 

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

@@ -128,7 +128,7 @@ type Type struct {
 	Vargen int32 // unique name for OTYPE/ONAME
 	Lineno int32
 
-	Nname  *Node
+	nname  *Node
 	Argwid int64
 
 	// most nodes
@@ -454,6 +454,12 @@ func (t *Type) wantEtype(et EType) {
 	}
 }
 
+func (t *Type) wantEtype2(et1, et2 EType) {
+	if t.Etype != et1 && t.Etype != et2 {
+		Fatalf("want %v or %v, but have %v", et1, et2, t)
+	}
+}
+
 func (t *Type) RecvsP() **Type {
 	t.wantEtype(TFUNC)
 	return &t.Type
@@ -527,6 +533,18 @@ func (t *Type) Wrapped() *Type {
 	return t.Type
 }
 
+// Nname returns the associated function's nname.
+func (t *Type) Nname() *Node {
+	t.wantEtype2(TFUNC, TINTERMETH)
+	return t.nname
+}
+
+// Nname sets the associated function's nname.
+func (t *Type) SetNname(n *Node) {
+	t.wantEtype2(TFUNC, TINTERMETH)
+	t.nname = n
+}
+
 func (t *Type) Methods() *Fields {
 	// TODO(mdempsky): Validate t?
 	return &t.methods

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

@@ -3418,7 +3418,7 @@ func typecheckfunc(n *Node) {
 		return
 	}
 	n.Type = t
-	t.Nname = n.Func.Nname
+	t.SetNname(n.Func.Nname)
 	rcvr := t.Recv()
 	if rcvr != nil && n.Func.Shortname != nil {
 		addmethod(n.Func.Shortname.Sym, t, nil, true, n.Func.Nname.Nointerface)
@@ -3465,7 +3465,7 @@ var ntypecheckdeftype int
 var methodqueue []*Node
 
 func domethod(n *Node) {
-	nt := n.Type.Nname
+	nt := n.Type.Nname()
 	nt = typecheck(nt, Etype)
 	if nt.Type == nil {
 		// type check failed; leave empty func