__copyright__ = """
Copyright (c) 2011, Eric Bainville
Copyright (c) 2015, Ilya Efimoff
All rights reserved.
"""

__license__ = """
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.

3. Neither the name of the copyright holder nor the names of its contributors
may be used to endorse or promote products derived from this software without
specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
"""

LOCAL_MEM_FACTOR = 1


# {{{ defines

defines = """//CL//

% if dtype == "double":
    #if __OPENCL_C_VERSION__ < 120
    #pragma OPENCL EXTENSION cl_khr_fp64: enable
    #endif
% endif

typedef ${dtype} data_t;
typedef ${idxtype} idx_t;
#if CONFIG_USE_VALUE
#define getKey(a) ((a).x)
#define getValue(a) ((a).y)
#define makeData(k,v) ((${dtype}2)((k),(v)))
#else
#define getKey(a) (a)
#define getValue(a) (0)
#define makeData(k,v) (k)
#endif

#ifndef BLOCK_FACTOR
#define BLOCK_FACTOR 1
#endif

#define inc  ${inc}
#define hinc ${inc>>1} //Half inc
#define qinc ${inc>>2} //Quarter inc
#define einc ${inc>>3} //Eighth of inc
#define dir  ${dir}

% if argsort:
#define ORDER(a,b,ay,by) { bool swap = reverse ^ (getKey(a)<getKey(b));${NS}
                         data_t auxa = a; data_t auxb = b;${NS}
                         idx_t auya = ay; idx_t auyb = by;${NS}
                         a = (swap)?auxb:auxa; b = (swap)?auxa:auxb;${NS}
                         ay = (swap)?auyb:auya; by = (swap)?auya:auyb;}
#define ORDERV(x,y,a,b) { bool swap = reverse ^ (getKey(x[a])<getKey(x[b]));${NS}
                        data_t auxa = x[a]; data_t auxb = x[b];${NS}
                        idx_t auya = y[a]; idx_t auyb = y[b];${NS}
                        x[a] = (swap)?auxb:auxa; x[b] = (swap)?auxa:auxb;${NS}
                        y[a] = (swap)?auyb:auya; y[b] = (swap)?auya:auyb;}
#define B2V(x,y,a)  { ORDERV(x,y,a,a+1) }
#define B4V(x,y,a)  { for (int i4=0;i4<2;i4++) { ORDERV(x,y,a+i4,a+i4+2) } B2V(x,y,a) B2V(x,y,a+2) }
#define B8V(x,y,a)  { for (int i8=0;i8<4;i8++) { ORDERV(x,y,a+i8,a+i8+4) } B4V(x,y,a) B4V(x,y,a+4) }
#define B16V(x,y,a) { for (int i16=0;i16<8;i16++) { ORDERV(x,y,a+i16,a+i16+8) } B8V(x,y,a) B8V(x,y,a+8) }
% else:
#define ORDER(a,b) { bool swap = reverse ^ (getKey(a)<getKey(b)); data_t auxa = a; data_t auxb = b; a = (swap)?auxb:auxa; b = (swap)?auxa:auxb; }
#define ORDERV(x,a,b) { bool swap = reverse ^ (getKey(x[a])<getKey(x[b]));${NS}
      data_t auxa = x[a]; data_t auxb = x[b];${NS}
      x[a] = (swap)?auxb:auxa; x[b] = (swap)?auxa:auxb; }
#define B2V(x,a) { ORDERV(x,a,a+1) }
#define B4V(x,a) { for (int i4=0;i4<2;i4++) { ORDERV(x,a+i4,a+i4+2) } B2V(x,a) B2V(x,a+2) }
#define B8V(x,a) { for (int i8=0;i8<4;i8++) { ORDERV(x,a+i8,a+i8+4) } B4V(x,a) B4V(x,a+4) }
#define B16V(x,a) { for (int i16=0;i16<8;i16++) { ORDERV(x,a+i16,a+i16+8) } B8V(x,a) B8V(x,a+8) }
% endif
#define nsize ${nsize}   //Total next dimensions sizes sum. (Block size)
#define dsize ${dsize}   //Dimension size
"""         # noqa: E501

# }}}


# {{{ B2

ParallelBitonic_B2 = """//CL//
// N/2 threads
//ParallelBitonic_B2
__kernel void run(__global data_t * data\\
% if argsort:
, __global idx_t * index)
% else:
)
% endif
{
  int t  = get_global_id(0) % (dsize>>1); // thread index
  int gt = get_global_id(0) / (dsize>>1);
  int low = t & (inc - 1); // low order bits (below INC)
  int i = (t<<1) - low; // insert 0 at position INC
  int gi = i/dsize; // block index
  bool reverse = ((dir & i) == 0);// ^ (gi%2); // asc/desc order

  int offset = (gt/nsize)*nsize*dsize+(gt%nsize);
  data  += i*nsize + offset; // translate to first value
% if argsort:
  index += i*nsize + offset; // translate to first value
% endif

  // Load data
  data_t x0 = data[  0];
  data_t x1 = data[inc*nsize];
% if argsort:
  // Load index
  idx_t i0 = index[  0];
  idx_t i1 = index[inc*nsize];
% endif

  // Sort
% if argsort:
  ORDER(x0,x1,i0,i1)
% else:
  ORDER(x0,x1)
% endif

  // Store data
  data[0  ] = x0;
  data[inc*nsize] = x1;
% if argsort:
  // Store index
  index[  0] = i0;
  index[inc*nsize] = i1;
% endif
}
"""

# }}}


# {{{ B4

ParallelBitonic_B4 = """//CL//
// N/4 threads
//ParallelBitonic_B4
__kernel void run(__global data_t * data\\
% if argsort:
, __global idx_t * index)
% else:
)
% endif
{
  int t  = get_global_id(0) % (dsize>>2); // thread index
  int gt = get_global_id(0) / (dsize>>2);
  int low = t & (hinc - 1); // low order bits (below INC)
  int i = ((t - low) << 2) + low; // insert 00 at position INC
  bool reverse = ((dir & i) == 0); // asc/desc order
  int offset = (gt/nsize)*nsize*dsize+(gt%nsize);
  data  += i*nsize + offset; // translate to first value
% if argsort:
  index += i*nsize + offset; // translate to first value
% endif

  // Load data
  data_t x0 = data[     0];
  data_t x1 = data[  hinc*nsize];
  data_t x2 = data[2*hinc*nsize];
  data_t x3 = data[3*hinc*nsize];
% if argsort:
  // Load index
  idx_t i0 = index[     0];
  idx_t i1 = index[  hinc*nsize];
  idx_t i2 = index[2*hinc*nsize];
  idx_t i3 = index[3*hinc*nsize];
% endif

  // Sort
% if argsort:
  ORDER(x0,x2,i0,i2)
  ORDER(x1,x3,i1,i3)
  ORDER(x0,x1,i0,i1)
  ORDER(x2,x3,i2,i3)
% else:
  ORDER(x0,x2)
  ORDER(x1,x3)
  ORDER(x0,x1)
  ORDER(x2,x3)
% endif

  // Store data
  data[     0] = x0;
  data[  hinc*nsize] = x1;
  data[2*hinc*nsize] = x2;
  data[3*hinc*nsize] = x3;
% if argsort:
  // Store index
  index[     0] = i0;
  index[  hinc*nsize] = i1;
  index[2*hinc*nsize] = i2;
  index[3*hinc*nsize] = i3;
% endif
}
"""

# }}}


# {{{ B8

ParallelBitonic_B8 = """//CL//
// N/8 threads
//ParallelBitonic_B8
__kernel void run(__global data_t * data\\
% if argsort:
, __global idx_t * index)
% else:
)
% endif
{
  int t  = get_global_id(0) % (dsize>>3); // thread index
  int gt = get_global_id(0) / (dsize>>3);
  int low = t & (qinc - 1); // low order bits (below INC)
  int i = ((t - low) << 3) + low; // insert 000 at position INC
  bool reverse = ((dir & i) == 0); // asc/desc order
  int offset = (gt/nsize)*nsize*dsize+(gt%nsize);

  data  += i*nsize + offset; // translate to first value
% if argsort:
  index += i*nsize + offset; // translate to first value
% endif

  // Load
  data_t x[8];
% if argsort:
  idx_t y[8];
% endif
  for (int k=0;k<8;k++) x[k] = data[k*qinc*nsize];
% if argsort:
  for (int k=0;k<8;k++) y[k] = index[k*qinc*nsize];
% endif

  // Sort
% if argsort:
  B8V(x,y,0)
% else:
  B8V(x,0)
% endif

  // Store
  for (int k=0;k<8;k++) data[k*qinc*nsize] = x[k];
% if argsort:
  for (int k=0;k<8;k++) index[k*qinc*nsize] = y[k];
% endif
}
"""

# }}}


# {{{ B16

ParallelBitonic_B16 = """//CL//
// N/16 threads
//ParallelBitonic_B16
__kernel void run(__global data_t * data\\
% if argsort:
, __global idx_t * index)
% else:
)
% endif
{
  int t  = get_global_id(0) % (dsize>>4); // thread index
  int gt = get_global_id(0) / (dsize>>4);
  int low = t & (einc - 1); // low order bits (below INC)
  int i = ((t - low) << 4) + low; // insert 0000 at position INC
  bool reverse = ((dir & i) == 0); // asc/desc order
  int offset = (gt/nsize)*nsize*dsize+(gt%nsize);

  data  += i*nsize + offset; // translate to first value
% if argsort:
  index += i*nsize + offset; // translate to first value
% endif

  // Load
  data_t x[16];
% if argsort:
  idx_t y[16];
% endif
  for (int k=0;k<16;k++) x[k] = data[k*einc*nsize];
% if argsort:
  for (int k=0;k<16;k++) y[k] = index[k*einc*nsize];
% endif

  // Sort
% if argsort:
  B16V(x,y,0)
% else:
  B16V(x,0)
% endif

  // Store
  for (int k=0;k<16;k++) data[k*einc*nsize] = x[k];
% if argsort:
  for (int k=0;k<16;k++) index[k*einc*nsize] = y[k];
% endif
}
"""

# }}}


# {{{ C4

# IF YOU RE-ENABLE THIS, YOU NEED TO ADJUST LOCAL_MEM_FACTOR TO 4

ParallelBitonic_C4 = """//CL//
//ParallelBitonic_C4
__kernel void run\\
% if argsort:
(__global data_t * data, __global idx_t * index, __local data_t * aux, __local idx_t * auy)
% else:
(__global data_t * data, __local data_t * aux)
% endif
{
  int t = get_global_id(0); // thread index
  int wgBits = 4*get_local_size(0) - 1; // bit mask to get index in local memory AUX (size is 4*WG)
  int linc,low,i;
  bool reverse;
  data_t x[4];
% if argsort:
  idx_t y[4];
% endif

  // First iteration, global input, local output
  linc = hinc;
  low = t & (linc - 1); // low order bits (below INC)
  i = ((t - low) << 2) + low; // insert 00 at position INC
  reverse = ((dir & i) == 0); // asc/desc order
  for (int k=0;k<4;k++) x[k] = data[i+k*linc];
% if argsort:
  for (int k=0;k<4;k++) y[k] = index[i+k*linc];
  B4V(x,y,0);
  for (int k=0;k<4;k++) auy[(i+k*linc) & wgBits] = y[k];
% else:
  B4V(x,0);
% endif
  for (int k=0;k<4;k++) aux[(i+k*linc) & wgBits] = x[k];
  barrier(CLK_LOCAL_MEM_FENCE);

  // Internal iterations, local input and output
  for ( ;linc>1;linc>>=2)
  {
    low = t & (linc - 1); // low order bits (below INC)
    i = ((t - low) << 2) + low; // insert 00 at position INC
    reverse = ((dir & i) == 0); // asc/desc order
    for (int k=0;k<4;k++) x[k] = aux[(i+k*linc) & wgBits];
% if argsort:
    for (int k=0;k<4;k++) y[k] = auy[(i+k*linc) & wgBits];
    B4V(x,y,0);
    barrier(CLK_LOCAL_MEM_FENCE);
    for (int k=0;k<4;k++) auy[(i+k*linc) & wgBits] = y[k];
% else:
    B4V(x,0);
    barrier(CLK_LOCAL_MEM_FENCE);
% endif
    for (int k=0;k<4;k++) aux[(i+k*linc) & wgBits] = x[k];
    barrier(CLK_LOCAL_MEM_FENCE);
  }

  // Final iteration, local input, global output, INC=1
  i = t << 2;
  reverse = ((dir & i) == 0); // asc/desc order
  for (int k=0;k<4;k++) x[k] = aux[(i+k) & wgBits];
% if argsort:
  for (int k=0;k<4;k++) y[k] = auy[(i+k) & wgBits];
  B4V(x,y,0);
  for (int k=0;k<4;k++) index[i+k] = y[k];
% else:
  B4V(x,0);
% endif
  for (int k=0;k<4;k++) data[i+k] = x[k];
}
"""         # noqa: E501

# }}}


# {{{ local merge

ParallelMerge_Local = """//CL//
// N threads, WG is workgroup size. Sort WG input blocks in each workgroup.
__kernel void run(__global const data_t * in,__global data_t * out,__local data_t * aux)
{
  int i = get_local_id(0); // index in workgroup
  int wg = get_local_size(0); // workgroup size = block size, power of 2

  // Move IN, OUT to block start
  int offset = get_group_id(0) * wg;
  in += offset; out += offset;

  // Load block in AUX[WG]
  aux[i] = in[i];
  barrier(CLK_LOCAL_MEM_FENCE); // make sure AUX is entirely up to date

  // Now we will merge sub-sequences of length 1,2,...,WG/2
  for (int length=1;length<wg;length<<=1)
  {
    data_t iData = aux[i];
    data_t iKey = getKey(iData);
    int ii = i & (length-1);  // index in our sequence in 0..length-1
    int sibling = (i - ii) ^ length; // beginning of the sibling sequence
    int pos = 0;
    for (int pinc=length;pinc>0;pinc>>=1) // increment for dichotomic search
    {
      int j = sibling+pos+pinc-1;
      data_t jKey = getKey(aux[j]);
      bool smaller = (jKey < iKey) || ( jKey == iKey && j < i );
      pos += (smaller)?pinc:0;
      pos = min(pos,length);
    }
    int bits = 2*length-1; // mask for destination
    int dest = ((ii + pos) & bits) | (i & ~bits); // destination index in merged sequence
    barrier(CLK_LOCAL_MEM_FENCE);
    aux[dest] = iData;
    barrier(CLK_LOCAL_MEM_FENCE);
  }

  // Write output
  out[i] = aux[i];
}
"""         # noqa: E501

# }}}


# {{{

ParallelBitonic_Local = """//CL//
// N threads, WG is workgroup size. Sort WG input blocks in each workgroup.
__kernel void run(__global const data_t * in,__global data_t * out,__local data_t * aux)
{
  int i = get_local_id(0); // index in workgroup
  int wg = get_local_size(0); // workgroup size = block size, power of 2

  // Move IN, OUT to block start
  int offset = get_group_id(0) * wg;
  in += offset; out += offset;

  // Load block in AUX[WG]
  aux[i] = in[i];
  barrier(CLK_LOCAL_MEM_FENCE); // make sure AUX is entirely up to date

  // Loop on sorted sequence length
  for (int length=1;length<wg;length<<=1)
  {
    bool direction = ((i & (length<<1)) != 0); // direction of sort: 0=asc, 1=desc
    // Loop on comparison distance (between keys)
    for (int pinc=length;pinc>0;pinc>>=1)
    {
      int j = i + pinc; // sibling to compare
      data_t iData = aux[i];
      uint iKey = getKey(iData);
      data_t jData = aux[j];
      uint jKey = getKey(jData);
      bool smaller = (jKey < iKey) || ( jKey == iKey && j < i );
      bool swap = smaller ^ (j < i) ^ direction;
      barrier(CLK_LOCAL_MEM_FENCE);
      aux[i] = (swap)?jData:iData;
      barrier(CLK_LOCAL_MEM_FENCE);
    }
  }

  // Write output
  out[i] = aux[i];
}
"""         # noqa: E501

# }}}


# {{{ A

ParallelBitonic_A = """//CL//
__kernel void ParallelBitonic_A(__global const data_t * in)
{
  int i = get_global_id(0); // thread index
  int j = i ^ inc; // sibling to compare

  // Load values at I and J
  data_t iData = in[i];
  uint iKey = getKey(iData);
  data_t jData = in[j];
  uint jKey = getKey(jData);

  // Compare
  bool smaller = (jKey < iKey) || ( jKey == iKey && j < i );
  bool swap = smaller ^ (j < i) ^ ((dir & i) != 0);

  // Store
  in[i] = (swap)?jData:iData;
}
"""

# }}}


# {{{ local optim

ParallelBitonic_Local_Optim = """//CL//
__kernel void run\\
% if argsort:
(__global data_t * data, __global idx_t * index, __local data_t * aux, __local idx_t * auy)
% else:
(__global data_t * data, __local data_t * aux)
% endif
{
  int t  = get_global_id(0) % dsize; // thread index
  int gt = get_global_id(0) / dsize;
  int offset = (gt/nsize)*nsize*dsize+(gt%nsize);

  int i = get_local_id(0); // index in workgroup
  int wg = get_local_size(0); // workgroup size = block size, power of 2

  // Move IN, OUT to block start
  //int offset = get_group_id(0) * wg;
  data += offset;
  // Load block in AUX[WG]
  data_t iData = data[t*nsize];
  aux[i] = iData;
% if argsort:
  index += offset;
  // Load block in AUY[WG]
  idx_t iidx = index[t*nsize];
  auy[i] = iidx;
% endif
  barrier(CLK_LOCAL_MEM_FENCE); // make sure AUX is entirely up to date

  // Loop on sorted sequence length
  for (int pwg=1;pwg<=wg;pwg<<=1){
      int loffset = pwg*(i/pwg);
      int ii = i%pwg;
      for (int length=1;length<pwg;length<<=1){
        bool direction = ii & (length<<1); // direction of sort: 0=asc, 1=desc
        // Loop on comparison distance (between keys)
        for (int pinc=length;pinc>0;pinc>>=1){
          int j = ii ^ pinc; // sibling to compare
          data_t jData = aux[loffset+j];
% if argsort:
          idx_t jidx = auy[loffset+j];
% endif
          data_t iKey = getKey(iData);
          data_t jKey = getKey(jData);
          bool smaller = (jKey < iKey) || ( jKey == iKey && j < ii );
          bool swap = smaller ^ (ii>j) ^ direction;
          iData = (swap)?jData:iData; // update iData
% if argsort:
          iidx = (swap)?jidx:iidx; // update iidx
% endif
          barrier(CLK_LOCAL_MEM_FENCE);
          aux[loffset+ii] = iData;
% if argsort:
          auy[loffset+ii] = iidx;
% endif
          barrier(CLK_LOCAL_MEM_FENCE);
        }
      }
  }

  // Write output
  data[t*nsize] = iData;
% if argsort:
  index[t*nsize] = iidx;
% endif
}
"""         # noqa: E501

# }}}

# vim: filetype=pyopencl:fdm=marker
