1. 08 Jun, 2012 1 commit
    • Heinz-Bernd Eggenstein's avatar
      Bug #1608: clFFT use of native_sin , native_cos can cause validation problems · 48a3c019
      Heinz-Bernd Eggenstein authored
      Still experimental: replace calls to native_sin in clFFT
      This change explores the performance impacts of using a set of LUTs, precomputed on the CPU
      to perform sin(x_i) and cos(x_i) in a grid x_i= +/- 2*pi *i/N , N fixed.
      On a 6770M, this code is still ca 3% slower than the original native_sin/native_cos varaint
      for a BRP4-like transform
      This variant should have a very high accuracy, versions with lesser accuracy but
      higher performance should be explored next. Eventually the method should be selectable
      by a parameter to the plan creator as suggested by Bernd.
      TODO: - remove some diagnostic code,
            - optimze total size of LUTs perhaps by using
              cos(x) = sin(x+pi/2), so no need to keep separate LUTs for sin and cos, just one slighly longer with
              an additional alias pointer
            - try caching the LUTs in shared memory (using constant memory didn't help)
  2. 18 Mar, 2011 2 commits
  3. 16 Mar, 2011 2 commits
  4. 12 Jan, 2011 3 commits