feat: update funcStruct to use variadic, impl String

Co-authored-by: Ethan Lewis <[email protected]>

Author: jeff1010322

compiler/interface.go

@@ -248,6 +248,7 @@ func (c *compilerContext) getTypeCode(typ types.Type) llvm.Value {
 				types.NewVar(token.NoPos, nil, "ptrTo", types.Typ[types.UnsafePointer]),
 				types.NewVar(token.NoPos, nil, "inCount", types.Typ[types.Uint16]),
 				types.NewVar(token.NoPos, nil, "outCount", types.Typ[types.Uint16]),
+				types.NewVar(token.NoPos, nil, "variadic", types.Typ[types.Bool]),
 				types.NewVar(token.NoPos, nil, "fields", types.NewArray(types.Typ[types.UnsafePointer], int64(typ.Params().Len()+typ.Results().Len()))),
 			)
 		}
@@ -409,13 +410,9 @@ func (c *compilerContext) getTypeCode(typ types.Type) llvm.Value {
 			typeFields = []llvm.Value{c.getTypeCode(types.NewPointer(typ))}
 			// TODO: methods
 		case *types.Signature:
-			v := typ.Results().Len()
+			v := 0
 			if typ.Variadic() {
-				// set variadic to 1
-				v = v | (1 << 15)
-			} else {
-				// set variadic to 0
-				v = v & ^(1 << 15)
+				v = 1
 			}
 
 			var vars []*types.Var
@@ -433,9 +430,9 @@ func (c *compilerContext) getTypeCode(typ types.Type) llvm.Value {
 			}
 			typeFields = []llvm.Value{c.getTypeCode(types.NewPointer(typ)),
 				llvm.ConstInt(c.ctx.Int16Type(), uint64(typ.Params().Len()), false),
-				llvm.ConstInt(c.ctx.Int16Type(), uint64(v), false),
+				llvm.ConstInt(c.ctx.Int16Type(), uint64(typ.Results().Len()), false),
+				llvm.ConstInt(c.ctx.Int1Type(), uint64(v), false),
 			}
-
 			typeFields = append(typeFields, llvm.ConstArray(c.dataPtrType, fields))
 		}
 		// Prepend metadata byte.

src/reflect/type.go

@@ -489,9 +489,10 @@ type structField struct {
 
 type funcType struct {
 	rawType
-	ptrType  *rawType
+	ptrTo    *rawType
 	inCount  uint16
 	outCount uint16
+	variadic bool
 	fields   [1]*rawType // the remaining fields are all of type funcField
 }
 
@@ -606,6 +607,28 @@ func (t *rawType) String() string {
 		}
 		s += " }"
 		return s
+	case Func:
+
+		f := "func("
+		for i := 0; i < t.NumIn(); i++ {
+			if i > 0 {
+				f += ", "
+			}
+			f += t.In(i).String()
+		}
+		f += ") "
+
+		var rets string
+		for i := 0; i < t.NumOut(); i++ {
+			if i > 0 {
+				rets += ", "
+			}
+			rets += t.Out(i).String()
+		}
+		if t.NumOut() > 1 {
+			rets = "(" + rets + ")"
+		}
+		return f + rets
 	case Interface:
 		// TODO(dgryski): Needs actual method set info
 		return "interface {}"
@@ -1050,7 +1073,7 @@ func (t *rawType) IsVariadic() bool {
 	if t.Kind() != Func {
 		panic("reflect: IsVariadic of non-func type")
 	}
-	return (*funcType)(unsafe.Pointer(t)).outCount&(1<<15) != 0
+	return (*funcType)(unsafe.Pointer(t)).variadic
 }
 
 func (t *rawType) NumIn() int {
@@ -1156,12 +1179,15 @@ func (t *rawType) Out(i int) Type {
 	if t.Kind() != Func {
 		panic(errTypeField)
 	}
-	i = i + int((*funcType)(unsafe.Pointer(t)).inCount)
+
 	descriptor := (*funcType)(unsafe.Pointer(t.underlying()))
-	if uint(i) > uint(descriptor.inCount) && uint(i) <= uint(descriptor.outCount+descriptor.inCount) {
+	if uint(i) >= uint(descriptor.outCount) {
 		panic("reflect: field index out of range")
 	}
 
+	// Shift the index by the number of input parameters.
+	i = i + int((*funcType)(unsafe.Pointer(t)).inCount)
+
 	pointer := (unsafe.Add(unsafe.Pointer(&descriptor.fields[0]), uintptr(i)*unsafe.Sizeof(unsafe.Pointer(nil))))
 	return (*rawType)(*(**rawType)(pointer))
 }