encoding/asn1: use reflect.TypeAssert to improve performance

Use "reflect.TypeAssert" can gain some performance improvements: goos: darwin goarch: arm64 pkg: encoding/asn1 cpu: Apple M4 │ old │ new │ │ sec/op │ sec/op vs base │ ObjectIdentifierString-10 51.48n ± 1% 49.72n ± 2% -3.41% (p=0.000 n=10) Marshal-10 7.549µ ± 0% 7.466µ ± 1% -1.10% (p=0.000 n=10) Unmarshal-10 1.808µ ± 0% 1.798µ ± 0% -0.58% (p=0.000 n=10) geomean 889.0n 873.8n -1.70% │ old │ new │ │ B/op │ B/op vs base │ ObjectIdentifierString-10 32.00 ± 0% 32.00 ± 0% ~ (p=1.000 n=10) ¹ Marshal-10 7.336Ki ± 0% 7.336Ki ± 0% ~ (p=1.000 n=10) ¹ Unmarshal-10 432.0 ± 0% 432.0 ± 0% ~ (p=1.000 n=10) ¹ geomean 470.0 470.0 +0.00% ¹ all samples are equal │ old │ new │ │ allocs/op │ allocs/op vs base │ ObjectIdentifierString-10 1.000 ± 0% 1.000 ± 0% ~ (p=1.000 n=10) ¹ Marshal-10 271.0 ± 0% 271.0 ± 0% ~ (p=1.000 n=10) ¹ Unmarshal-10 24.00 ± 0% 24.00 ± 0% ~ (p=1.000 n=10) ¹ geomean 18.67 18.67 +0.00% ¹ all samples are equal Updates #62121

Author: apocelipes

src/encoding/asn1/marshal.go

@@ -460,17 +460,20 @@ func makeBody(value reflect.Value, params fieldParameters) (e encoder, err error
 case flagType:
 return bytesEncoder(nil), nil
 case timeType:
-t := value.Interface().(time.Time)
+t, _ := reflect.TypeAssert[time.Time](value)
 if params.timeType == TagGeneralizedTime || outsideUTCRange(t) {
 return makeGeneralizedTime(t)
 }
 return makeUTCTime(t)
 case bitStringType:
-return bitStringEncoder(value.Interface().(BitString)), nil
+v, _ := reflect.TypeAssert[BitString](value)
+return bitStringEncoder(v), nil
 case objectIdentifierType:
-return makeObjectIdentifier(value.Interface().(ObjectIdentifier))
+v, _ := reflect.TypeAssert[ObjectIdentifier](value)
+return makeObjectIdentifier(v)
 case bigIntType:
-return makeBigInt(value.Interface().(*big.Int))
+v, _ := reflect.TypeAssert[*big.Int](value)
+return makeBigInt(v)
 }
 
 switch v := value; v.Kind() {
@@ -605,7 +608,7 @@ func makeField(v reflect.Value, params fieldParameters) (e encoder, err error) {
 }
 
 if v.Type() == rawValueType {
-rv := v.Interface().(RawValue)
+rv, _ := reflect.TypeAssert[RawValue](v)
 if len(rv.FullBytes) != 0 {
 return bytesEncoder(rv.FullBytes), nil
 }
@@ -650,7 +653,8 @@ func makeField(v reflect.Value, params fieldParameters) (e encoder, err error) {
 tag = params.stringType
 }
 case TagUTCTime:
-if params.timeType == TagGeneralizedTime || outsideUTCRange(v.Interface().(time.Time)) {
+t, _ := reflect.TypeAssert[time.Time](v)
+if params.timeType == TagGeneralizedTime || outsideUTCRange(t) {
 tag = TagGeneralizedTime
 }
 }