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en Abort('Duplicate Identifier ' + N);

if NEntry = MaxEntry then Abort('Symbol Table Full');

Inc(NEntry);

ST[NEntry] := N;

SType[NEntry] := T;

end;

{–}

{ Get an Identifier }

procedure GetName;

begin

NewLine;

if not IsAlpha(Look) then Expected('Name');

Value := '';

while IsAlNum(Look) do begin

Value := Value + UpCase(Look);

GetChar;

end;

SkipWhite;

end;

{–}

{ Get a Number }

function GetNum: integer;

var Val: integer;

begin

NewLine;

if not IsDigit(Look) then Expected('Integer');

Val := 0;

while IsDigit(Look) do begin

Val := 10 * Val + Ord(Look) – Ord('0');

GetChar;

end;

GetNum := Val;

SkipWhite;

end;

{–}

{ Get an Identifier and Scan it for Keywords }

procedure Scan;

begin

GetName;

Token := KWcode[Lookup(Addr(KWlist), Value, NKW) + 1];

end;

{–}

{ Match a Specific Input String }

procedure MatchString(x: string);

begin

if Value <> x then Expected('''' + x + '''');

end;

{–}

{ Output a String with Tab }

procedure Emit(s: string);

begin

Write(TAB, s);

end;

{–}

{ Output a String with Tab and CRLF }

procedure EmitLn(s: string);

begin

Emit(s);

WriteLn;

end;

{–}

{ Generate a Unique Label }

function NewLabel: string;

var S: string;

begin

Str(LCount, S);

NewLabel := 'L' + S;

Inc(LCount);

end;

{–}

{ Post a Label To Output }

procedure PostLabel(L: string);

begin

WriteLn(L, ':');

end;

{–}

{ Clear the Primary Register }

procedure Clear;

begin

EmitLn('CLR D0');

end;

{–}

{ Negate the Primary Register }

procedure Negate;

begin

EmitLn('NEG D0');

end;

{–}

{ Complement the Primary Register }

procedure NotIt;

begin

EmitLn('NOT D0');

end;

{–}

{ Load a Constant Value to Primary Register }

procedure LoadConst(n: integer);

begin

Emit('MOVE #');

WriteLn(n, ',D0');

end;

{–}

{ Load a Variable to Primary Register }

procedure LoadVar(Name: string);

begin

if not InTable(Name) then Undefined(Name);

EmitLn('MOVE ' + Name + '(PC),D0');

end;

{–}

{ Push Primary onto Stack }

procedure Push;

begin

EmitLn('MOVE D0,-(SP)');

end;

{–}

{ Add Top of Stack to Primary }

procedure PopAdd;

begin

EmitLn('ADD (SP)+,D0');

end;

{–}

{ Subtract Primary from Top of Stack }

procedure PopSub;

begin

EmitLn('SUB (SP)+,D0');

EmitLn('NEG D0');

end;

{–}

{ Multiply Top of Stack by Primary }

procedure PopMul;

begin

EmitLn('MULS (SP)+,D0');

end;

{–}

{ Divide Top of Stack by Primary }

procedure PopDiv;

begin

EmitLn('MOVE (SP)+,D7');

EmitLn('EXT.