Support for PTX with ComputeCpp was added in 2017 and enabled SYCL developers to target Nvidia devices using OpenCL and the PTX instruction set. See our blog for more background on this.
In November 2020 Codeplay this support has been superseded by our work to add Nvidia device support to DPC++, you can find out more about this work here.
We strongly recommend using the Nvidia device support provided with DPC++, setup instructions for this are available on the open source LLVM project.