encoding/gob: remove unused ut and atyp parameters

Found by github.com/mvdan/unparam.

Change-Id: Ic97f05a2ecb5b17caa36aafe403e2266abea3e0e
Reviewed-on: https://go-review.googlesource.com/37836
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

src/encoding/gob/decode.go

@@ -430,7 +430,7 @@ type decEngine struct {
 // decodeSingle decodes a top-level value that is not a struct and stores it in value.
 // Such values are preceded by a zero, making them have the memory layout of a
 // struct field (although with an illegal field number).
-func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, value reflect.Value) {
+func (dec *Decoder) decodeSingle(engine *decEngine, value reflect.Value) {
 	state := dec.newDecoderState(&dec.buf)
 	defer dec.freeDecoderState(state)
 	state.fieldnum = singletonField
@@ -446,7 +446,7 @@ func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, value refl
 // differ from ut.indir, which was computed when the engine was built.
 // This state cannot arise for decodeSingle, which is called directly
 // from the user's value, not from the innards of an engine.
-func (dec *Decoder) decodeStruct(engine *decEngine, ut *userTypeInfo, value reflect.Value) {
+func (dec *Decoder) decodeStruct(engine *decEngine, value reflect.Value) {
 	state := dec.newDecoderState(&dec.buf)
 	defer dec.freeDecoderState(state)
 	state.fieldnum = -1
@@ -538,7 +538,7 @@ func (dec *Decoder) decodeArrayHelper(state *decoderState, value reflect.Value,
 // decodeArray decodes an array and stores it in value.
 // The length is an unsigned integer preceding the elements. Even though the length is redundant
 // (it's part of the type), it's a useful check and is included in the encoding.
-func (dec *Decoder) decodeArray(atyp reflect.Type, state *decoderState, value reflect.Value, elemOp decOp, length int, ovfl error, helper decHelper) {
+func (dec *Decoder) decodeArray(state *decoderState, value reflect.Value, elemOp decOp, length int, ovfl error, helper decHelper) {
 	if n := state.decodeUint(); n != uint64(length) {
 		errorf("length mismatch in decodeArray")
 	}
@@ -813,7 +813,7 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProg
 			ovfl := overflow(name)
 			helper := decArrayHelper[t.Elem().Kind()]
 			op = func(i *decInstr, state *decoderState, value reflect.Value) {
-				state.dec.decodeArray(t, state, value, *elemOp, t.Len(), ovfl, helper)
+				state.dec.decodeArray(state, value, *elemOp, t.Len(), ovfl, helper)
 			}
 
 		case reflect.Map:
@@ -854,7 +854,7 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProg
 			}
 			op = func(i *decInstr, state *decoderState, value reflect.Value) {
 				// indirect through enginePtr to delay evaluation for recursive structs.
-				dec.decodeStruct(*enginePtr, ut, value)
+				dec.decodeStruct(*enginePtr, value)
 			}
 		case reflect.Interface:
 			op = func(i *decInstr, state *decoderState, value reflect.Value) {
@@ -1197,9 +1197,9 @@ func (dec *Decoder) decodeValue(wireId typeId, value reflect.Value) {
 			name := base.Name()
 			errorf("type mismatch: no fields matched compiling decoder for %s", name)
 		}
-		dec.decodeStruct(engine, ut, value)
+		dec.decodeStruct(engine, value)
 	} else {
-		dec.decodeSingle(engine, ut, value)
+		dec.decodeSingle(engine, value)
 	}
 }