function TestBuild(Lines: TStrings): string;
const
  SizeAlloc = 32 * 4;
var
  i, Len, current, c: Cardinal;
  wd: string;
begin
  i := Lines.Count;
  if i = 0 then
    Exit('''' + '''');

  Len := SizeAlloc;
  SetLength(Result, Len);

  wd := '''' + Lines[0] + '''';
  current := Length(wd);
  Move(wd[1], Result[1], current * SizeOf(Char));

  for i := 1 to i - 1 do
  begin
    wd := '#13#10' + '''' + Lines[i] + '''';

    c := Length(wd);

    if (current + c) > Len then
    begin
      Inc(Len, SizeAlloc);
      SetLength(Result, Len);
    end;

    Move(wd[1], Result[current], c * SizeOf(Char));
    Inc(current, c);
  end;
  SetLength(Result, current - 1);
end;

unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type
  TForm1 = class(TForm)
    Memo1: TMemo;
    Button1: TButton;
    Memo2: TMemo;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure FormCreate(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

var
  T, T1, T3: Int64;
  i, A: integer;

function sprintf(S: PAnsiChar; const Format: PAnsiChar): integer; cdecl; varargs; external 'msvcrt.dll';

function PrintTime(T: Int64): AnsiString;
var
  A, b: Int64;
begin
  Result := '';
  if QueryPerformanceCounter(A) and QueryPerformanceFrequency(b) then
  begin
    SetLength(Result, 25);
    SetLength(Result, sprintf(PAnsiChar(Result), '%f', single((A - T) / b)));
  end;
end;

function BuildStringLiteral(List: TStrings): String;
const
  sLineBreak = '#13#10';
var
  i, Sz, Len: integer;
begin
  if List.Count = 0 then
  begin
    Result := '''' + '''';
    Exit;
  end;
  Sz := 0;
  for i := 0 to List.Count - 1 do
    Inc(Sz, Length(List[i]) + 8);
  Dec(Sz, 6);
  SetLength(Result, Sz);
  Sz := 1;
  for i := 0 to List.Count - 1 do
  begin
    Result[Sz] := '''';
    Len := Length(List[i]);
    CopyMemory(@Result[Sz + 1], @List[i][1], Len * SizeOf(Char));
    Inc(Sz, Len + 2);
    Result[Sz - 1] := '''';
    if i < List.Count - 1 then
      CopyMemory(@Result[Sz], @sLineBreak[1], Length(sLineBreak) * SizeOf(Char));
    Inc(Sz, 6);
  end;
end;

function TestBuildStringLiteral(List: TStrings): AnsiString;
var
  arr: Pointer;
  i, r: integer;
begin
  QueryPerformanceCounter(T1);
  for r := 0 to 3 do
    for i := 0 to 1000 do
      BuildStringLiteral(List);

  Result := PrintTime(T1);
end;

function TestBuild(Lines: TStrings): string;
const
  SizeAlloc = 32 * 4;
var
  i, Len, current, c: Cardinal;
  wd: string;
begin
  i := Lines.Count;
  if i = 0 then
    Exit('''' + '''');

  Len := SizeAlloc;
  SetLength(Result, Len);

  wd := '''' + Lines[0] + '''';
  current := Length(wd);
  Move(wd[1], Result[1], current * SizeOf(Char));

  for i := 1 to i - 1 do
  begin
    wd := '#13#10' + '''' + Lines[i] + '''';

    c := Length(wd);

    if (current + c) > Len then
    begin
      Inc(Len, SizeAlloc);
      SetLength(Result, Len);
    end;

    Move(wd[1], Result[current], c * SizeOf(Char));
    Inc(current, c);
  end;
  SetLength(Result, current - 1);
end;

function TestTestBuild(List: TStrings): AnsiString;
var
  arr: Pointer;
  i, r: integer;
begin
  QueryPerformanceCounter(T1);
  for r := 0 to 3 do
    for i := 0 to 1000 do
      TestBuild(List);

  Result := PrintTime(T1);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  Memo2.Lines.Add('TestBuild: ' + TestTestBuild(Memo1.Lines));
  Memo2.Lines.Add('BuildStringLiteral: ' + TestBuildStringLiteral(Memo1.Lines));
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  ShowMessage(TestBuild(Memo1.Lines));
  ShowMessage(BuildStringLiteral(Memo1.Lines));
end;

procedure TForm1.FormCreate(Sender: TObject);
var
  i: integer;
  S: string;
begin
  S := '';
  for i := 0 to 100 do
    S := S + 'Ijisjergije488reujiorjt' + i.ToString + #13#10;
  Memo1.Text := S;
end;

end.