More private members

instruction.go

@@ -5,18 +5,18 @@ import "bytes"
 import "github.com/lunixbochs/struc"
 import "github.com/pkg/errors"
 
-const InstructionBytes = 32
-
 type Instruction struct {
 	OpCode   OpCodeType
 	Reserved [4]byte
 	Operand1 Operand
 	Operand2 Operand
 
-	opHandler OpHandler `struc:"skip"`
+	opHandler opHandler `struc:"skip"`
 }
 
-func NewInstruction(byteCode []byte) (*Instruction, error) {
+const instructionBytes = 32
+
+func NewInstructionFromByteCode(byteCode []byte) (*Instruction, error) {
 	instr := &Instruction{}
 
 	reader := bytes.NewReader(byteCode)
@@ -28,3 +28,25 @@ func NewInstruction(byteCode []byte) (*Instruction, error) {
 
 	return instr, nil
 }
+
+func NewInstructionsFromByteCode(byteCode []byte) ([]*Instruction, error) {
+	instrs := []*Instruction{}
+
+	for start := 0; start < len(byteCode); start += instructionBytes {
+		chunk := byteCode[start : start+instructionBytes]
+		instr, err := NewInstructionFromByteCode(chunk)
+		if err != nil {
+			return nil, errors.Wrapf(err, "At byte offset %d", start)
+		}
+		instrs = append(instrs, instr)
+	}
+
+	if len(instrs) == 0 || instrs[len(instrs)-1].OpCode != OpReturn {
+		// Add implicit return at the end of each function
+		instrs = append(instrs, &Instruction{
+			OpCode: OpReturn,
+		})
+	}
+
+	return instrs, nil
+}