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diff --git "a/c\316\273ash/CLasH/Normalize.hs" "b/c\316\273ash/CLasH/Normalize.hs"
index 999704f..cf33b7b 100644
--- "a/c\316\273ash/CLasH/Normalize.hs"
+++ "b/c\316\273ash/CLasH/Normalize.hs"
@@ -327,35 +327,35 @@ inlinenonreptop = everywhere ("inlinenonrep", inlinebind ((Monad.liftM not) . is
 --------------------------------
 -- Top level function inlining
 --------------------------------
--- This transformation inlines top level bindings that have been generated by
--- the compiler and are really simple. Really simple currently means that the
--- normalized form only contains a single binding, which catches most of the
+-- This transformation inlines simple top level bindings. Simple
+-- currently means that the body is only a single application (though
+-- the complexity of the arguments is not currently checked) or that the
+-- normalized form only contains a single binding. This should catch most of the
 -- cases where a top level function is created that simply calls a type class
 -- method with a type and dictionary argument, e.g.
 --   fromInteger = GHC.Num.fromInteger (SizedWord D8) $dNum
 -- which is later called using simply
 --   fromInteger (smallInteger 10)
--- By inlining such calls to simple, compiler generated functions, we prevent
--- huge amounts of trivial components in the VHDL output, which the user never
--- wanted. We never inline user-defined functions, since we want to preserve
--- all structure defined by the user. Currently this includes all functions
--- that were created by funextract, since we would get loops otherwise.
+--
+-- These useless wrappers are created by GHC automatically. If we don't
+-- inline them, we get loads of useless components cluttering the
+-- generated VHDL.
+--
+-- Note that the inlining could also inline simple functions defined by
+-- the user, not just GHC generated functions. It turns out to be near
+-- impossible to reliably determine what functions are generated and
+-- what functions are user-defined. Instead of guessing (which will
+-- inline less than we want) we will just inline all simple functions.
 --
 -- Only functions that are actually completely applied and bound by a
 -- variable in a let expression are inlined. These are the expressions
 -- that will eventually generate instantiations of trivial components.
 -- By not inlining any other reference, we also prevent looping problems
 -- with funextract and inlinedict.
---
--- Note that "defined by the compiler" isn't completely watertight, since GHC
--- doesn't seem to set all those names as "system names", we apply some
--- guessing here.
 inlinetoplevel, inlinetopleveltop :: Transform
-inlinetoplevel (LetBinding:_) expr =
+inlinetoplevel (LetBinding:_) expr | not (is_fun expr) =
   case collectArgs expr of
-	-- Any system name is candidate for inlining. Never inline
-	-- user-defined functions, to preserve structure.
-	(Var f, args) | not $ isUserDefined f -> do
+	(Var f, args) -> do
 	  body_maybe <- needsInline f
 	  case body_maybe of
 		Just body -> do