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Fast way to exchange the contents of two variables

procedure SwapVars1(var u, v; Size: Integer); var x: Pointer; begin GetMem(x, Size); try System.move(u, x^, Size); System.move(v, u, Size); System.move(x^, v, Size); finally FreeMem(x); end; end; procedure SwapVars2(var Source, Dest; Size: Integer); // By Mike Heydon, mheydon@eoh.co.za begin asm push edi push esi mov esi,Source mov edi,Dest mov ecx,Size cld @1: mov al,[edi] xchg [esi],al inc si stosb loop @1 pop esi pop edi end; end; procedure TForm1.Button2Click(Sender: TObject); begin SwapVars1(X1, X2, SizeOf(Integer)); end;