When a device function calls a host function or vice versa, this is wrong-sided
reference. Currently clang immediately diagnose it. This is different from nvcc
behavior, where it is diagnosed only if the function is really emitted.
Current clang behavior causes false alarms for valid use cases.
This patch let clang always defer diagnostics for wrong-sided
reference.
Differential Revision: https://reviews.llvm.org/D83893
norecurse function attr indicates the function is not called recursively
directly or indirectly.
Add norecurse to OpenCL functions, SYCL functions in device compilation
and CUDA/HIP kernels.
Although there is LLVM pass adding norecurse to functions, it only works
for whole-program compilation. Also FE adding norecurse can make that
pass run faster since functions with norecurse do not need to be checked
again.
Differential Revision: https://reviews.llvm.org/D73651