Simplified file structure

src/core/ExpressionToRegister.go

@@ -0,0 +1,87 @@
+package core
+
+import (
+	"git.akyoto.dev/cli/q/src/asm"
+	"git.akyoto.dev/cli/q/src/ast"
+	"git.akyoto.dev/cli/q/src/cpu"
+	"git.akyoto.dev/cli/q/src/errors"
+	"git.akyoto.dev/cli/q/src/expression"
+	"git.akyoto.dev/cli/q/src/token"
+	"git.akyoto.dev/cli/q/src/types"
+)
+
+// ExpressionToRegister puts the result of an expression into the specified register.
+func (f *Function) ExpressionToRegister(node *expression.Expression, register cpu.Register) (types.Type, error) {
+	f.SaveRegister(register)
+
+	if node.IsFolded {
+		f.RegisterNumber(asm.MOVE, register, node.Value)
+		return types.Int, nil
+	}
+
+	if node.IsLeaf() {
+		return f.TokenToRegister(node.Token, register)
+	}
+
+	if ast.IsFunctionCall(node) {
+		fn, err := f.CompileCall(node)
+
+		if register != f.CPU.Output[0] {
+			f.RegisterRegister(asm.MOVE, register, f.CPU.Output[0])
+		}
+
+		if fn == nil || len(fn.ReturnTypes) == 0 {
+			return types.Any, err
+		}
+
+		return fn.ReturnTypes[0], err
+	}
+
+	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)
+		return types.Int, err
+	}
+
+	if len(node.Children) == 1 {
+		if !node.Token.IsUnaryOperator() {
+			return types.Invalid, errors.New(errors.MissingOperand, f.File, node.Token.End())
+		}
+
+		typ, err := f.ExpressionToRegister(node.Children[0], register)
+
+		if err != nil {
+			return typ, err
+		}
+
+		return typ, f.ExecuteRegister(node.Token, register)
+	}
+
+	left := node.Children[0]
+	right := node.Children[1]
+	final := register
+
+	if f.UsesRegister(right, register) {
+		register = f.NewRegister()
+	}
+
+	typ, err := f.ExpressionToRegister(left, register)
+
+	if err != nil {
+		return types.Invalid, err
+	}
+
+	if typ == types.Pointer && (node.Token.Kind == token.Add || node.Token.Kind == token.Sub) && right.Token.Kind == token.Identifier && f.VariableByName(right.Token.Text(f.File.Bytes)).Type == types.Pointer {
+		typ = types.Int
+	}
+
+	err = f.Execute(node.Token, register, right)
+
+	if register != final {
+		f.RegisterRegister(asm.MOVE, final, register)
+		f.FreeRegister(register)
+	}
+
+	return typ, err
+}