Implemented length storage of allocated memory

src/asm/Assembler.go

@@ -24,5 +24,5 @@ func (a *Assembler) SetData(label string, bytes []byte) {
 		a.Data = data.Data{}
 	}
 
-	a.Data[label] = bytes
+	a.Data.Insert(label, bytes)
 }

src/asm/Memory.go

@@ -4,7 +4,7 @@ import "git.akyoto.dev/cli/q/src/cpu"
 
 type Memory struct {
 	Base           cpu.Register
-	Offset         byte
+	Offset         int8
 	OffsetRegister cpu.Register
 	Length         byte
 }

src/asmc/resolvePointers.go

@@ -80,7 +80,7 @@ restart:
 	dataStart, _ := fs.Align(c.codeStart+Address(len(c.code)), config.Align)
 
 	for _, pointer := range c.dataPointers {
-		address := config.BaseAddress + dataStart + pointer.Resolve()
+		address := config.BaseAddress + dataStart + pointer.Resolve() + 8
 		slice := c.code[pointer.Position : pointer.Position+4]
 		binary.LittleEndian.PutUint32(slice, uint32(address))
 	}

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

src/register/SaveRegister.go

@@ -26,4 +26,5 @@ func (f *Machine) SaveRegister(register cpu.Register) {
 	newRegister := f.NewRegister()
 	f.RegisterRegister(asm.MOVE, newRegister, register)
 	variable.Register = newRegister
+	f.FreeRegister(register)
 }

src/x86/Load.go

@@ -3,6 +3,6 @@ package x86
 import "git.akyoto.dev/cli/q/src/cpu"
 
 // LoadRegister loads from memory into a register.
-func LoadRegister(code []byte, destination cpu.Register, offset byte, length byte, source cpu.Register) []byte {
+func LoadRegister(code []byte, destination cpu.Register, offset int8, length byte, source cpu.Register) []byte {
 	return memoryAccess(code, 0x8A, 0x8B, source, offset, length, destination)
 }

src/x86/Load_test.go

@@ -12,7 +12,7 @@ func TestLoadRegister(t *testing.T) {
 	usagePatterns := []struct {
 		Destination cpu.Register
 		Source      cpu.Register
-		Offset      byte
+		Offset      int8
 		Length      byte
 		Code        []byte
 	}{

src/x86/Store.go

@@ -7,7 +7,7 @@ import (
 )
 
 // StoreNumber stores a number into the memory address included in the given register.
-func StoreNumber(code []byte, register cpu.Register, offset byte, length byte, number int) []byte {
+func StoreNumber(code []byte, register cpu.Register, offset int8, length byte, number int) []byte {
 	code = memoryAccess(code, 0xC6, 0xC7, register, offset, length, 0b000)
 
 	switch length {
@@ -22,6 +22,6 @@ func StoreNumber(code []byte, register cpu.Register, offset byte, length byte, n
 }
 
 // StoreRegister stores the contents of the `source` register into the memory address included in the given register.
-func StoreRegister(code []byte, register cpu.Register, offset byte, length byte, source cpu.Register) []byte {
+func StoreRegister(code []byte, register cpu.Register, offset int8, length byte, source cpu.Register) []byte {
 	return memoryAccess(code, 0x88, 0x89, register, offset, length, source)
 }

src/x86/Store_test.go

@@ -11,7 +11,7 @@ import (
 func TestStoreNumber(t *testing.T) {
 	usagePatterns := []struct {
 		Register cpu.Register
-		Offset   byte
+		Offset   int8
 		Length   byte
 		Number   int
 		Code     []byte
@@ -159,7 +159,7 @@ func TestStoreNumber(t *testing.T) {
 func TestStoreRegister(t *testing.T) {
 	usagePatterns := []struct {
 		RegisterTo   cpu.Register
-		Offset       byte
+		Offset       int8
 		Length       byte
 		RegisterFrom cpu.Register
 		Code         []byte

src/x86/memoryAccess.go

@@ -3,7 +3,7 @@ package x86
 import "git.akyoto.dev/cli/q/src/cpu"
 
 // memoryAccess encodes a memory access.
-func memoryAccess(code []byte, opCode8 byte, opCode32 byte, register cpu.Register, offset byte, numBytes byte, source cpu.Register) []byte {
+func memoryAccess(code []byte, opCode8 byte, opCode32 byte, register cpu.Register, offset int8, numBytes byte, source cpu.Register) []byte {
 	opCode := opCode32
 
 	if numBytes == 1 {
@@ -27,7 +27,7 @@ func memoryAccess(code []byte, opCode8 byte, opCode32 byte, register cpu.Registe
 	}
 
 	if mod == AddressMemoryOffset8 {
-		code = append(code, offset)
+		code = append(code, byte(offset))
 	}
 
 	return code