Class-Based Kernels - 2022.1 English

Vitis Model Composer User Guide (UG1483)

Document ID
UG1483
Release Date
2022-05-26
Version
2022.1 English

Vitis Model Composer supports importing the C++ kernel class to have constructor parameters for specifying parameter values. You need to use an AIE Class Kernel block from the AI Engine Library as shown.

Figure 1. AIE Class Kernel

Double-clicking the block symbol displays the parameters of the AI Engine class kernel block as shown in the following figure.

Figure 2. AIE Class Kernel: Block Parameters

The block mask parameters need to be updated in order to import the kernel function as a block. The following table provides details on the parameters and description for each parameter.

Table 1. AIE Class Kernel: Parameters
Parameter Name Parameter Type Criticality Description
Kernel header file String Mandatory Name of the header file that contains the kernel class and registerKernelClass method declarations. The string could be just the file name, a relative path to the file or an absolute path of the file. Use the browse button to select the file.

This field does not accept environmental variables.

Kernel class String Mandatory Name of the kernel class which contains member variables and kernel member function.
Kernel function String Mandatory Name of the kernel member function for which the block is to be created. This function should be registered using the registerKernelClass method in kernel header file.
Kernel source file String String

Name of the source file that contains the kernel member function definition and non-default constructor parameter values are specified.

The string could be the file name, a relative path to the file or an absolute path of the file.

This field does not accepts environmental variables.

Kernel search paths Vector of Strings Optional

If the kernel header file or the kernel source file are not found using the value provided through the Kernel header file or Kernel source file fields, respectively, then the paths provided through Kernel search paths are used to find the files.

This parameter allows use of environment variables while specifying paths for the kernel header file and the kernel source file. The environment variable can be used in either ${ENV} or $ENV format.

Preprocessor options   Optional Optional preprocessor arguments for downstream compilation with specific preprocessor options.

The following two preprocessor option formats are accepted and multiple can be selected: -D<name> and -D<name>=<definition> separated by a comma. That is, the optional argument must begin with -D and if the the option <definition> value is not provided, it is assumed to be 1.

The AI Engine class kernel block supports all the kernel functions that a normal AI Engine kernel block can support and the Block Parameters dialog box which appears after double-clicking on the AI Engine class kernel block is the same irrespective of whether the kernel member function is Window-based or Stream-based. To edit the header file or source file, you can click the Edit button (immediately after the browse button).