This patch introduces a hook to encode descriptor set
and binding number into `spv.globalVariable`'s symbolic name. This
allows to preserve this information, and at the same time legalize
the global variable for the conversion to LLVM dialect.
This is required for `mlir-spirv-cpu-runner` to convert kernel
arguments into LLVM.
Also, a couple of some nits added:
- removed unused comment
- changed to a capital letter in the comment
Reviewed By: mravishankar
Differential Revision: https://reviews.llvm.org/D86515
e850558cdc