Clover: Build with MSVC
This is the first steps towards being able to use Clover (e.g. with LLVMPipe) on Windows. High-level changes:
- Remove requirement to include AMD's native LLVM backend in Clover.
- Support CMake instead of configtool as a way of finding LLVM for Clover.
- Fix up some nonportable code
- Work around some MSVC quirks
- Switch to a .def file for Windows exports, since
__declspec(dllexport)needs to match on declaration/definition, and CL APIs are declared in
With a cheap hack to use the static pipe loader, I was able to run CL LLVMPipe on Windows with this.
This addresses a couple of bullets from #3824