/* ============================================================================
Function: = Bitonic_sort_decr
Purpose: = Use bitonic sort to sort the keys in my_list into
= decreasing order.
==============================================================================
Input arg: = 1. my_rank: The size of the processors array.
= 2. my_list[]: A pointer to an array.
= 3. neighbors_list[]: A pointer to an array.
= 4. list_size: The size of the processors array.
= 5. partner_size: The size of partner pairing.
= 6. comm: The mpi communicator channel.
==============================================================================
Note: = len is a power of 2
=========================================================================== */
void Bitonic_sort_decr(int my_rank, int my_list[], int neighbors_list[],
int list_size, int partner_size, MPI_Comm comm)
{
unsigned xor_bit;
int partner, stage, stage_limit;
stage_limit = log_base2(partner_size);
xor_bit = 1 << (stage_limit - 1);
for(stage = 0; stage < stage_limit; stage++)
{
partner = my_rank ^ xor_bit;
if(my_rank > partner)
{
Merge_split(1, my_rank, list_size, my_list, neighbors_list,
partner, comm);
}
else
{
Merge_split(0, my_rank, list_size, my_list, neighbors_list,
partner, comm);
}
xor_bit = xor_bit >> 1;
}
} /* Bitonic_sort_decr */
void Par_bitonic_sort_decr(
int list_size /* in */,
KEY_T* local_list /* in/out */,
int proc_set_size /* in */,
MPI_Comm comm /* in */ ) {
unsigned eor_bit;
int proc_set_dim;
int stage;
int partner;
int my_rank;
MPI_Comm_rank(comm, &my_rank);
proc_set_dim = log_base2(proc_set_size);
eor_bit = 1 << (proc_set_dim - 1);
for (stage = 0; stage < proc_set_dim; stage++) {
partner = my_rank ^ eor_bit;
if (my_rank > partner)
Merge_split(list_size, local_list, LOW,
partner, comm);
else
Merge_split(list_size, local_list, HIGH,
partner, comm);
eor_bit = eor_bit >> 1;
}
} /* Par_bitonic_sort_decr */
