Ensure kernel metadata is correct on kernel replacement.

Author: maleadt

src/irgen.jl

@@ -1062,6 +1062,7 @@ function add_input_arguments!(@nospecialize(job::CompilerJob), mod::LLVM.Module,
     for (f, new_f) in workmap
         rewrite_uses!(f, new_f)
         @assert isempty(uses(f))
+        replace_metadata_uses!(f, new_f)
         erase!(f)
     end
 

src/metal.jl

@@ -497,6 +497,7 @@ function pass_by_reference!(@nospecialize(job::CompilerJob), mod::LLVM.Module, f
     # NOTE: if we ever have legitimate uses of the old function, create a shim instead
     fn = LLVM.name(f)
     @assert isempty(uses(f))
+    replace_metadata_uses!(f, new_f)
     erase!(f)
     LLVM.name!(new_f, fn)