DPCT1099#

Message#

Verify if the default value of the direction and placement used in the function <function name> is correct.

Detailed Help#

By default, the parameter direction_and_placement is not passed for dpct::fft::fft_engine::create(), dpct::fft::fft_engine::commit(), or dpct::fft::fft_engine::estimate_size(). In this case, a forward direction (if the current FFT is complex-to-complex) and out-of-place (false) are used as the default values in this API. The configuration of the direction and placement is reset when executing dpct::fft::fft_engine::compute() according to the argument passed with the compute() API. There might be performance issues caused by the reconfiguration.

To avoid the potential performance issues, specify the parameter direction_and_placement explicitly when calling dpct::fft::fft_engine::create() or dpct::fft::fft_engine::commit(), then the direction and placement information passed by the compute() API is ignored and no reconfiguration happens.

Suggestions to Fix#

If you received a warning for dpct::fft::fft_engine::create() or dpct::fft::fft_engine::commit():

  • If you are using an internal workspace and do not care about performance, you can ignore this warning.

  • If you do care about performance, specify the direction_and_placement parameter correctly.

If you received this warning for dpct::fft::fft_engine::estimate_size(), you need specify the direction_and_placement parameter correctly.