The FFT length in the clFFT library is limited to 2^24 SP and 2^22 DP respectively. What was the reason to do so? I'd like to tackle this in the open source version. But if there's a bigger limitation problem behind this (e.g. due to OpenCL itself), I'd like to know that first.
size_t SP_MAX_LEN = 1 << 24;
size_t DP_MAX_LEN = 1 << 22;