HLS Behavioral Differences - 2021.2 English

Vitis High-Level Synthesis User Guide (UG1399)

Document ID
UG1399
ft:locale
English (United States)
Release Date
2021-12-15
Version
2021.2 English

Vitis™ HLS brings some fundamental changes in the way HLS synthesizes the C code, supports language constructs, and supports existing commands, pragmas, and directives. For example, the std::complex<long double> data type is not supported in Vitis HLS, and should not be used. These changes have implications on the application QoR. Xilinx® recommends reviewing this section before using the tool.

Tip: Due to the behavioral differences between Vitis HLS and Vivado HLS, you might need to differentiate your code for use in the Vitis tool. To enable the same source code to be used in both tools, Vitis HLS supports the __VITIS_HLS__ predefined macro to encapsulate source code written specifically for use in that tool. Use #if defined( __VITIS_HLS__) type pre-processor declarations to encapsulate tool specific code.