fix: recursive for large and deep struct

dev/decoder/compile_struct.go

@@ -9,6 +9,10 @@ import (
 	"github.com/bytedance/sonic/dev/internal/caching"
 )
 
+const (
+    _MAX_FIELDS = 50        // cutoff at 50 fields struct
+)
+
 func (c *compiler) compileIntStringOption(vt reflect.Type) decFunc {
 	switch vt.Size() {
 	case 4:
@@ -80,9 +84,20 @@ func (c *compiler) compileFieldStringOption(vt reflect.Type) decFunc {
 	}
 }
 
+
 func (c *compiler) compileStruct(vt reflect.Type) decFunc {
 	c.enter(vt)
 	defer c.exit(vt)
+	if c.depth >= c.opts.MaxInlineDepth || (c.counts > 0 &&  vt.NumField() >= _MAX_FIELDS) {
+		return &recuriveDecoder{
+			typ: rt.UnpackType(vt),
+		}
+	} else {
+		return c.compileStructBody(vt)
+	}
+}
+
+func (c *compiler) compileStructBody(vt reflect.Type) decFunc {
 	fv := resolver.ResolveStruct(vt)
 	fm := caching.CreateFieldMap(len(fv))
 

dev/decoder/compiler.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"reflect"
 
+	"github.com/bytedance/sonic/option"
 	"github.com/bytedance/sonic/dev/internal/rt"
 	"github.com/bytedance/sonic/dev/internal/caching"
 )
@@ -30,15 +31,22 @@ func findOrCompile(vt *rt.GoType) (decFunc, error) {
 type compiler struct {
 	visited map[reflect.Type]bool
 	depth   int
+	counts  int
+	opts option.CompileOptions
 }
 
 func newCompiler() *compiler {
 	return &compiler{
 		visited: make(map[reflect.Type]bool),
-		depth:   0,
+		opts:  option.DefaultCompileOptions(),
 	}
 }
 
+func (self *compiler) apply(opts option.CompileOptions) *compiler {
+	self.opts = opts
+	return self
+}
+
 const _CompileMaxDepth = 4096
 
 func (c *compiler) enter(vt reflect.Type) {
@@ -113,6 +121,9 @@ func (c *compiler) compile(vt reflect.Type) decFunc {
 }
 
 func (c *compiler) compileBasic(vt reflect.Type) decFunc {
+	defer func() {
+		c.counts += 1
+	}()
 	switch vt.Kind() {
 	case reflect.Bool:
 		return &boolDecoder{}
@@ -279,6 +290,8 @@ func (c *compiler) compileSliceBytes(vt reflect.Type) decFunc {
 }
 
 func (c *compiler) compileInterface(vt reflect.Type) decFunc {
+	c.enter(vt)
+	defer c.exit(vt)
 	if vt.NumMethod() == 0 {
 		return &efaceDecoder{}
 	}