3.6.1.4 Bound Loop

Syntax
#pragma HLS loop bounds lower(<int>) upper(<int>)
Description
Specifies the bounds on the number of times a loop will iterate. This pragma does not affect the synthesized circuit. It's only used to improve reporting. By manually specifying bounds, the overall loop latency can be computed and reported.
Parameters
ParameterValueOptionalDefaultDescription
lowerIntegerNo-Lower bound
upperIntegerNo-Upper bound
Position
Before the beginning of the loop. If there is a loop label, the pragma should be placed after the label.
Examples
#pragma HLS loop bounds lower(5) upper(10)
// Here, the bounds tell us the trip count (number of iterations) will be between 5 and 10 inclusively.
for (int i = 0; i < N; i++) {
  ...
}