adapt to changes in UnionSplitInfo (#600)

due to JuliaLang/julia#55815

---------

Co-authored-by: Shuhei Kadowaki <40514306+aviatesk@users.noreply.github.com>

src/reflection.jl

@@ -179,7 +179,11 @@ function process_info(interp::AbstractInterpreter, @nospecialize(info::CCCallInf
             is_cached(mi) ? mici : UncachedCallInfo(mici)
         end for match::Core.MethodMatch in matches]
     elseif isa(info, UnionSplitInfo)
-        return mapreduce(process_recursive, vcat, info.matches; init=CallInfo[])::Vector{CallInfo}
+        @static if hasfield(UnionSplitInfo, :split)
+            return mapreduce(process_recursive, vcat, info.split; init=CallInfo[])::Vector{CallInfo}
+        else
+            return mapreduce(process_recursive, vcat, info.matches; init=CallInfo[])::Vector{CallInfo}
+        end
     elseif isa(info, UnionSplitApplyCallInfo)
         return mapreduce(process_recursive, vcat, info.infos; init=CallInfo[])::Vector{CallInfo}
     elseif isa(info, ApplyCallInfo)