Compiles a plugin's C runtime wrappers into a single LLVM IR module.

add_mim_runtime(<plugin-name>
    SOURCES <source>...
    [INSTALL])

All SOURCES are compiled with clang and merged into a single textual module <libdir>/mim/rt/<plugin-name>_rt.ll, next to the plugins. A backend locates that one file via the driver's search paths (see mim.plug.ll.Emitter.load_rt_module) and either embeds it into or links it with its emitted module (see -X <plugin-name>:rt=embed|extern). Producing a single module keeps the runtime addressable by one well-known name regardless of how many source files it is split into.

A single source is compiled directly to the module; multiple sources are compiled to bitcode and merged with llvm-link (which must then be on PATH).

If clang is unavailable (see MIM_CLANG) or MIM_BUILD_LL_RUNTIME is off, the command is a no-op; the runtime is simply not built.