[SYCL] DPC++ support runtime compilation?

[DongBaiYue]

Is your feature request related to a problem? Please describe
I'm trying to add SYCL backend to TVM. In it, kernel source code is automatically generated at runtime, so source code needs to be compiled at runtime.

Describe the solution you would like
Runtime compilation similar to nvrtc.

Describe alternatives you have considered
I'm know this is a little tricky in SYCL, because SYCL is based on a single-source model. The alternative I'm taking now is to write the generated source code to a file and compile the file to a dynamic link library. This alternative is somewhat heavy.
Any suggestions?

[steffenlarsen]

Hi @DongBaiYue! I see that you have already seen the draft extension in #11985, but in case anyone else finds this issue, there is an extension for such functionality in progress.