public override void Compile(Assembly assembly, Scope scope, Register target)
{
throw new CompileError("Comparisons in general expressions are not implemented");
//Evaluate in reverse in case both need to go on the stack
var secondTarget = scope.FindFreeRegister();
if (Scope.IsRegister((Register)secondTarget)) scope.UseRegister(secondTarget);
(ChildNodes[1] as CompilableNode).Compile(assembly, scope, (Register)secondTarget);
if (AsString == "==" || AsString == "!=")
{
(ChildNodes[0] as CompilableNode).Compile(assembly, scope, Register.STACK);
if (target == Register.STACK)
{
assembly.Add("SET", Scope.TempRegister, "0x0", "Equality onto stack");
assembly.Add((AsString == "==" ? "IFE" : "IFN"), "POP", Scope.GetRegisterLabelSecond(secondTarget));
assembly.Add("SET", Scope.TempRegister, "0x1");
assembly.Add("SET", "PUSH", Scope.TempRegister);
}
else
{
assembly.Add("SET", Scope.GetRegisterLabelFirst((int)target), "0x0", "Equality into register");
assembly.Add((AsString == "==" ? "IFE" : "IFN"), "POP", Scope.GetRegisterLabelSecond(secondTarget));
assembly.Add("SET", Scope.GetRegisterLabelFirst((int)target), "0x1");
}
}
if (secondTarget == (int)Register.STACK)
scope.stackDepth -= 1;
else
scope.FreeRegister(secondTarget);
}
private static void PushRegister(Assembly assembly, Scope scope, Register r)
{
assembly.Add("SET", "PUSH", Scope.GetRegisterLabelSecond((int)r), "Saving register");
scope.FreeRegister(0);
scope.stackDepth += 1;
}