修正接口互查

_tests/type-assert-01.wa

@@ -6,6 +6,7 @@ func main {
 
 	println("ok:", ok) // BUG: OK 始终返回 false
 	println("xerr:", xerr)
+	println("err.MyError():", err.MyError())
 }
 
 type myIface interface {

internal/backends/compiler_wat/wir/value_interface.go

@@ -167,17 +167,20 @@ func (v *aInterface) emitQueryInterface(destType ValueType, commaOk bool) (insts
 	insts = append(insts, wat.NewInstCall("$wa.runtime.getItab")) //itab
 
 	insts = append(insts, wat.NewInstCall("$wa.runtime.DupI32"))
-	ifBlock := wat.NewInstIf(nil, nil, nil)
-	insts = append(insts, ifBlock)
+	ifs := wat.NewInstIf(nil, nil, nil)
+	insts = append(insts, ifs)
 	if commaOk {
-		ifBlock.Ret = append(ifBlock.Ret, wat.I32{})
-		ifBlock.True = append(ifBlock.True, wat.NewInstConst(wat.I32{}, "1"))
-		ifBlock.False = append(ifBlock.False, wat.NewInstConst(wat.I32{}, "0"))
+		ifs.Ret = []wat.ValueType{wat.I32{}, wat.I32{}}
+		ifs.True = append(ifs.True, v.Extract("eq").EmitPush()...)    //eq
+		ifs.True = append(ifs.True, wat.NewInstConst(wat.I32{}, "1")) //ok:true
+
+		ifs.False = append(ifs.False, v.Extract("eq").EmitPush()...)    //eq
+		ifs.False = append(ifs.False, wat.NewInstConst(wat.I32{}, "0")) //ok:false
 	} else {
-		ifBlock.False = append(ifBlock.False, wat.NewInstUnreachable())
+		ifs.False = append(ifs.False, wat.NewInstUnreachable())
+		insts = append(insts, v.Extract("eq").EmitPush()...) //eq
 	}
 
-	insts = append(insts, v.Extract("eq").EmitPush()...)
 	return
 }