The old JIT was a fork of a pared-back version of MSVC; this was for all platforms, except the .NET Compact framework, which was for embedded stuff, and it was its own fork.
There were other weird things like C++/CLI which was a full-fat MSVC fork used to compile C++ either into .NET IL or x86 code which could be embedded into .NET assemblies, but could still call into .NET code.
But what most people think of as .NET (Framework) was definitely using the old MSVC-based JIT
There were other weird things like C++/CLI which was a full-fat MSVC fork used to compile C++ either into .NET IL or x86 code which could be embedded into .NET assemblies, but could still call into .NET code.
But what most people think of as .NET (Framework) was definitely using the old MSVC-based JIT