cmd/compile/internal/types2: removed deprecated API entry points

We don't need to keep them around in types2.
Switched a couple of uses of NewSignature to NewSignatureType.

Change-Id: I62880c2b49ec82caa9362ed8a798cfc3bcea300e
Reviewed-on: https://go-review.googlesource.com/c/go/+/353397
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>

src/cmd/compile/internal/noder/reader2.go

@@ -316,7 +316,7 @@ func (r *reader2) signature(recv *types2.Var) *types2.Signature {
 	results := r.params()
 	variadic := r.bool()
 
-	return types2.NewSignature(recv, params, results, variadic)
+	return types2.NewSignatureType(recv, nil, nil, params, results, variadic)
 }
 
 func (r *reader2) params() *types2.Tuple {

src/cmd/compile/internal/types2/interface.go

@@ -27,19 +27,6 @@ func (t *Interface) typeSet() *_TypeSet { return computeInterfaceTypeSet(t.check
 // emptyInterface represents the empty interface
 var emptyInterface = Interface{complete: true, tset: &topTypeSet}
 
-// NewInterface returns a new interface for the given methods and embedded types.
-// NewInterface takes ownership of the provided methods and may modify their types
-// by setting missing receivers.
-//
-// Deprecated: Use NewInterfaceType instead which allows arbitrary embedded types.
-func NewInterface(methods []*Func, embeddeds []*Named) *Interface {
-	tnames := make([]Type, len(embeddeds))
-	for i, t := range embeddeds {
-		tnames[i] = t
-	}
-	return NewInterfaceType(methods, tnames)
-}
-
 // NewInterfaceType returns a new interface for the given methods and embedded types.
 // NewInterfaceType takes ownership of the provided methods and may modify their types
 // by setting missing receivers.
@@ -76,12 +63,6 @@ func (t *Interface) ExplicitMethod(i int) *Func { return t.methods[i] }
 // NumEmbeddeds returns the number of embedded types in interface t.
 func (t *Interface) NumEmbeddeds() int { return len(t.embeddeds) }
 
-// Embedded returns the i'th embedded defined (*Named) type of interface t for 0 <= i < t.NumEmbeddeds().
-// The result is nil if the i'th embedded type is not a defined type.
-//
-// Deprecated: Use EmbeddedType which is not restricted to defined (*Named) types.
-func (t *Interface) Embedded(i int) *Named { tname, _ := t.embeddeds[i].(*Named); return tname }
-
 // EmbeddedType returns the i'th embedded type of interface t for 0 <= i < t.NumEmbeddeds().
 func (t *Interface) EmbeddedType(i int) Type { return t.embeddeds[i] }
 

src/cmd/compile/internal/types2/signature.go

@@ -28,16 +28,6 @@ type Signature struct {
 	variadic bool           // true if the last parameter's type is of the form ...T (or string, for append built-in only)
 }
 
-// NewSignature returns a new function type for the given receiver, parameters,
-// and results, either of which may be nil. If variadic is set, the function
-// is variadic, it must have at least one parameter, and the last parameter
-// must be of unnamed slice type.
-//
-// Deprecated: Use NewSignatureType instead which allows for type parameters.
-func NewSignature(recv *Var, params, results *Tuple, variadic bool) *Signature {
-	return NewSignatureType(recv, nil, nil, params, results, variadic)
-}
-
 // NewSignatureType creates a new function type for the given receiver,
 // receiver type parameters, type parameters, parameters, and results. If
 // variadic is set, params must hold at least one parameter and the last

src/cmd/compile/internal/types2/universe.go

@@ -86,7 +86,7 @@ func defPredeclaredTypes() {
 		obj := NewTypeName(nopos, nil, "error", nil)
 		obj.setColor(black)
 		res := NewVar(nopos, nil, "", Typ[String])
-		sig := NewSignature(nil, nil, NewTuple(res), false)
+		sig := NewSignatureType(nil, nil, nil, nil, NewTuple(res), false)
 		err := NewFunc(nopos, nil, "Error", sig)
 		ityp := &Interface{nil, obj, []*Func{err}, nil, nil, true, nil}
 		computeInterfaceTypeSet(nil, nopos, ityp) // prevent races due to lazy computation of tset