Bound

The bound annotation provides a quick, simple way of annotating the approximate sizes of data consumed by the application. This is primarily useful in automated design space exploration, where the ideal parallelization factor or memory size may depend on the size of the data the accelerator will be processing.

The bound annotation is not a guarantee, so no operation optimizations are done as a result of this annotation. It is purely used to help drive runtime estimation.

While bound can be used outside of the Accel scopes, it currently has no use except in hardware tuning.

To set the bound of a given value, use the syntax:

bound(x) = 64

This tells the compiler to expect the value x to be approximately 64 at runtime.