Implemented length storage of allocated memory

src/core/CompileAssignArray.go

@@ -40,7 +40,7 @@ func (f *Function) CompileAssignArray(node *ast.Assign) error {
 			return err
 		}
 
-		memory.Offset = byte(offset)
+		memory.Offset = int8(offset)
 	} else {
 		_, indexRegister, isTemporary, err := f.Evaluate(index)
 

src/core/CompileAssignField.go

@@ -32,7 +32,7 @@ func (f *Function) CompileAssignField(node *ast.Assign) error {
 
 	memory := asm.Memory{
 		Base:           variable.Register,
-		Offset:         byte(field.Offset),
+		Offset:         int8(field.Offset),
 		OffsetRegister: math.MaxUint8,
 		Length:         byte(field.Type.Size()),
 	}

src/core/CompileCall.go

@@ -27,6 +27,14 @@ func (f *Function) CompileCall(root *expression.Expression) (*Function, error) {
 		name = nameNode.Token.Text(f.File.Bytes)
 
 		switch name {
+		case "len":
+			return &Function{
+				Output: []*Output{
+					{
+						Type: types.Int,
+					},
+				},
+			}, f.CompileLen(root)
 		case "syscall":
 			return nil, f.CompileSyscall(root)
 		case "new":

src/core/CompileLen.go

@@ -0,0 +1,26 @@
+package core
+
+import (
+	"math"
+
+	"git.akyoto.dev/cli/q/src/asm"
+	"git.akyoto.dev/cli/q/src/expression"
+)
+
+// CompileLen returns the length of a slice.
+func (f *Function) CompileLen(root *expression.Expression) error {
+	_, register, isTemporary, err := f.Evaluate(root.Children[1])
+
+	if err != nil {
+		return err
+	}
+
+	f.SaveRegister(f.CPU.Output[0])
+	f.MemoryRegister(asm.LOAD, asm.Memory{Base: register, Offset: -8, OffsetRegister: math.MaxUint8, Length: 8}, f.CPU.Output[0])
+
+	if isTemporary {
+		f.FreeRegister(register)
+	}
+
+	return nil
+}

src/core/ExpressionToRegister.go

@@ -40,7 +40,7 @@ func (f *Function) ExpressionToRegister(node *expression.Expression, register cp
 	if node.Token.Kind == token.Array {
 		array := f.VariableByName(node.Children[0].Token.Text(f.File.Bytes))
 		offset, err := f.Number(node.Children[1].Token)
-		f.MemoryRegister(asm.LOAD, asm.Memory{Base: array.Register, Offset: byte(offset), Length: 1}, register)
+		f.MemoryRegister(asm.LOAD, asm.Memory{Base: array.Register, Offset: int8(offset), Length: 1}, register)
 		return types.Int, err
 	}
 
@@ -51,7 +51,7 @@ func (f *Function) ExpressionToRegister(node *expression.Expression, register cp
 		right := node.Children[1]
 		name = right.Token.Text(f.File.Bytes)
 		field := variable.Type.(*types.Pointer).To.(*types.Struct).FieldByName(name)
-		f.MemoryRegister(asm.LOAD, asm.Memory{Base: variable.Register, Offset: byte(field.Offset), Length: byte(field.Type.Size())}, register)
+		f.MemoryRegister(asm.LOAD, asm.Memory{Base: variable.Register, Offset: int8(field.Offset), Length: byte(field.Type.Size())}, register)
 		return field.Type, nil
 	}
 

src/core/TokenToRegister.go

@@ -1,6 +1,8 @@
 package core
 
 import (
+	"encoding/binary"
+
 	"git.akyoto.dev/cli/q/src/asm"
 	"git.akyoto.dev/cli/q/src/cpu"
 	"git.akyoto.dev/cli/q/src/errors"
@@ -45,7 +47,12 @@ func (f *Function) TokenToRegister(t token.Token, register cpu.Register) (types.
 	case token.String:
 		data := t.Bytes(f.File.Bytes)
 		data = String(data)
-		label := f.AddBytes(data)
+
+		slice := make([]byte, len(data)+8)
+		binary.LittleEndian.PutUint64(slice, uint64(len(data)))
+		copy(slice[8:], data)
+
+		label := f.AddBytes(slice)
 		f.SaveRegister(register)
 		f.RegisterLabel(asm.MOVE, register, label)
 		return types.PointerAny, nil