Free Running Pipeline - Free Running Pipeline - 2026.1 English - UG1448

Vitis HLS Messaging (UG1448)

Document ID
UG1448
Release Date
2026-06-23
Version
2026.1 English

Description

Warning: [200-1975] Disabling free running pipeline (frp) architecture on pipeline 'VITIS_LOOP_11_2' in module 'COM_Pipeline_VITIS_LOOP_11_2', because the pipeline has no blocking I/O (enable free running pipeline would get no gain as there is no big fanout issue of blocking I/O).

Explanation

FRP is not applied because there is no blocking I/O with big fanout; therefore, there is no advantage to using FRP for this pipelined loop.

Example


void COM(int a[SIZE])
{
    int i,j,temp;

    for(i = 0; i < SIZE-1; i++)
    {
      for(j = 0; j < SIZE-1-i; j++)
      {
        #pragma HLS pipeline II=1 style=frp
        #pragma HLS latency min=2 max=3
        if(a[j] < a[j+1])
        {
            temp = a[j+1];
            a[j+1] = a[j];
            a[j] = temp;
        }
      }
     }
        for(i = 0; i < SIZE; i++)
             printf("%d\n",a[i]);
}