Intel® High Level Synthesis Compiler Pro Edition: Reference Manual

ID 683349
Date 10/04/2021
Public

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10.3. System of Tasks Simulation

When you simulate a system of tasks design where the completion of a task function is not synchronized with an ihc::collect call, use the ihc_hls_set_component_wait_cycle testbench API function to allow output from that task function to be returned after the component function finishes running.

By default, the simulation process simulates an additional 100 cycles after a component asserts the done signal to ensure all operations have propagated back to the testbench. This function tells the simulation process for the specified component to continue running for the specified number of cycles in addition to the default wait period of 100 cycles.

If you do not use this function in your testbench, the latency of some task functions might make your simulation output inaccurate or cause your simulation testbench to hang..

For an example of a valid systems of task design where the completion of a task function is not synchronized with an ihc::collect call, see Example 3 of a Valid ihc::launch/ihc::collect Sequence.

Table 26.   Intel® HLS Compiler Testbench API for System of Tasks
Function Description
ihc_hls_set_component_wait_cycle This function tells the simulation process to continue running for a specified number of additional cycles (beyond the default wait period of 100 cycles) after the done signal for the specified component is observed.