Compute the main order asymptotics of the integral $\int_0^{\infty}e^{itx-e^x}dx$, as $\mid t \mid \to \infty$.

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I have found this integral interesting because it does not fall into any of the Fourier/steepest descent/integration by parts methods to compute asymptotics! The Mellin transform of this function is also ill-defined !

Has someone come across a similar oscillating integral ? Any novel ideas would be greatly appreciated. Thanks in advance.