fftm -- Fftm (multiple fast fourier transform) benchmark
Single precision
 Fixed rows, sweeping FFT size:
   -1 -- op  : out-of-place CC fwd fft
   -2 -- ip  : In-place CC fwd fft
   -3 -- pop : Psuedo out-of-place CC fwd fft
   -4 -- pip1: Psuedo in-place v1 CC fwd fft
   -5 -- pip2: Psuedo in-place v2 CC fwd fft
   -6 -- bv  : By-value CC fwd fft

 Parameters (for sweeping FFT size, cases 1 through 6)
  -p:rows ROWS -- set number of pulses (default 64)

 Fixed FFT size, sweeping number of FFTs:
  -11 -- op  : out-of-place CC fwd fft
  -12 -- ip  : In-place CC fwd fft
  -13 -- pop : Psuedo out-of-place CC fwd fft
  -14 -- pip1: Psuedo in-place v1 CC fwd fft
  -15 -- pip2: Psuedo in-place v2 CC fwd fft
  -16 -- bv  : By-value CC fwd fft

 Parameters (for sweeping number of FFTs, cases 11 through 16)
  -p:size SIZE -- size of pulse (default 2048)