don't require varargs to be in last position to exploit cached type info

base/compiler/ssair/inlining2.jl

@@ -576,18 +576,7 @@ function analyze_method!(idx, f, ft, metharg, methsp, method, stmt, atypes, sv,
         return ConstantCase(quoted(linfo.inferred_const), method, Any[methsp...], metharg)
     end
 
-    # Handle vararg functions
-    prevararg_rewritten_atypes = atypes
-    isva = na > 0 && method.isva
-    if isva
-        @assert length(atypes) >= na - 1
-        va_type = tuple_tfunc(Tuple{Any[widenconst(atypes[i]) for i in 1:length(atypes)]...})
-        atypes = Any[atypes[1:(na - 1)]..., va_type]
-    end
-
-    # Go see if we already have a pre-inferred result. Use prevararg_rewritten_atypes
-    # for the lookup, since that's what inference used when it populated the cache.
-    res = find_inferred(linfo, prevararg_rewritten_atypes, sv)
+    res = find_inferred(linfo, atypes, sv)
     res === nothing && return nothing
 
     if length(res::Tuple) == 1