cf = With[{
      mandel = Block[{z = #, c = #},
        Catch@Do[If[Abs[z] > 2, Throw@i]; z = z^2 + c, {i, 100}]] &
    },
   Compile[{},Table[mandel[y + x I], {x, -1, 1, 0.005}, {y, -2, 0.5, 0.005}]]
  ];
ArrayPlot[cf[]]