ap_fifoprotocol. More specifically, the AXI-Stream (
axis) protocol does not support non-blocking accesses.
The term non-blocking means that lack of data (or too much data) on the
stream does not block the operation of a function or the
iteration of a loop. Non-blocking methods return a Boolean value
indicating the status of a read or write:
false otherwise. However, using
non-blocking APIs can lead to non-deterministic behavior which
cannot be fully validated during either C-simulation or
RTL/Co-simulation, and requires an RTL testbench to test it
exhaustively. Non-deterministic behavior can occur when reading
from an empty FIFO or writing to a full FIFO.
During C simulation, streams have an infinite size. It is therefore not possible to validate with C simulation if the stream is full. These methods can be verified only during RTL simulation when the FIFO sizes are defined (either the default size of 1, or an arbitrary size defined with the STREAM directive).
ap_ctrl_noneand the design contains any
hls::streamvariables that employ non-blocking behavior, C/RTL co-simulation is not guaranteed to complete.