source: branches/virtcpu fixed int/UInstructionWriter.pas

unit UInstructionWriter;

{$mode delphi}{$H+}

interface

uses
  Classes, SysUtils, UCpu;

type
  { TInstructionWriter }

  TInstructionWriter = class
  private
  public
    Cpu: TCpu;
    IP: T;
    procedure Write(Value: T);
    procedure NoOperation;
    procedure Load(R1, R2: Integer);
    procedure Halt;
    procedure LoadConst(R, Value: Integer);
    procedure LoadMemory(R1, R2: Integer);
    procedure StoreMemory(R1, R2: Integer);
    procedure Neg(R: Integer);
    procedure Input(R1, R2: Integer);
    procedure Output(R1, R2: Integer);
    procedure Subtract(R1, R2: Integer);
    procedure Jump(Addr: Integer);
    procedure JumpCond(Addr: Integer);
    procedure TestZero(R: Integer);
    {$IFDEF EXT_REL_JUMP}procedure JumpRelative(Addr: Integer);{$ENDIF}
    procedure SysCall;
    procedure Increment(R: Integer);
    procedure Decrement(R: Integer);
    constructor Create;
  end;


implementation

{ TInstructionWriter }

procedure TInstructionWriter.NoOperation;
begin
  Write(T(opNop));
end;

procedure TInstructionWriter.Load(R1, R2: Integer);
begin
  Write(T(opLoad));
  Write(R1);
  Write(R2);
end;

procedure TInstructionWriter.Halt;
begin
  Write(T(opHalt));
end;

procedure TInstructionWriter.LoadConst(R, Value: Integer);
begin
  Write(T(opLoadConst));
  Write(R);
  Write(Value);
end;

procedure TInstructionWriter.LoadMemory(R1, R2: Integer);
begin
  Write(T(opLoadMem));
  Write(R1);
  Write(R2);
end;

procedure TInstructionWriter.StoreMemory(R1, R2: Integer);
begin
  Write(T(opStoreMem));
  Write(R1);
  Write(R2);
end;

procedure TInstructionWriter.Neg(R: Integer);
begin
  Write(T(opNeg));
  Write(R);
end;

procedure TInstructionWriter.Input(R1, R2: Integer);
begin
  Write(T(opInput));
  Write(R1);
  Write(R2);
end;

procedure TInstructionWriter.Output(R1, R2: Integer);
begin
  Write(T(opOutput));
  Write(R1);
  Write(R2);
end;

procedure TInstructionWriter.Subtract(R1, R2: Integer);
begin
  Write(T(opSub));
  Write(R1);
  Write(R2);
end;

procedure TInstructionWriter.Jump(Addr: Integer);
begin
  Write(T(opJump));
  Write(Addr);
end;

procedure TInstructionWriter.JumpCond(Addr: Integer);
begin
  Write(T(opJumpCond));
  Write(Addr);
end;

procedure TInstructionWriter.TestZero(R: Integer);
begin
  Write(T(opTestZero));
  Write(R);
end;

procedure TInstructionWriter.SysCall;
begin
  Write(T(opSysCall));
end;

{$IFDEF EXT_REL_JUMP}
procedure TInstructionWriter.JumpRelative(Addr: Integer);
begin
  Write(T(opJumpRel));
  Write(Addr - IP - 1);
end;
{$ENDIF}

procedure TInstructionWriter.Increment(R: Integer);
begin
  Write(T(opInc));
  Write(R);
end;

procedure TInstructionWriter.Decrement(R: Integer);
begin
  Write(T(opDec));
  Write(R);
end;

constructor TInstructionWriter.Create;
begin
  IP := 0;
  Cpu := nil;
end;

procedure TInstructionWriter.Write(Value: T);
begin
  Cpu.Memory[IP] := Value;
  Inc(IP);
end;


end.