Merge branch 'master' of git://github.com/christiaanb/clash

[matthijs/master-project/cλash.git] / clash / CLasH / Normalize.hs

diff --git a/clash/CLasH/Normalize.hs b/clash/CLasH/Normalize.hs
index c27e93eb7803c0c4604492308cbccd9fadbc2864..11212f943df0678a4b9cef09fb52657ba06bc2dd 100644 (file)
--- a/clash/CLasH/Normalize.hs
+++ b/clash/CLasH/Normalize.hs
@@ -216,10 +216,15 @@ needsInline f = do
 -- body consisting of a bunch of nested lambdas containing a
 -- non-function value (e.g., a complete application).
 eta :: Transform
-eta c expr | is_fun expr && not (is_lam expr) && all (== LambdaBody) c = do
-  let arg_ty = (fst . Type.splitFunTy . CoreUtils.exprType) expr
-  id <- Trans.lift $ mkInternalVar "param" arg_ty
-  change (Lam id (App expr (Var id)))
+eta (AppFirst:_) expr = return expr
+-- Also don't apply to arguments, since this can cause loops with
+-- funextract. This isn't the proper solution, but due to an
+-- implementation bug in notappargs, this is how it used to work so far.
+eta (AppSecond:_) expr = return expr
+eta c expr | is_fun expr && not (is_lam expr) = do
+ let arg_ty = (fst . Type.splitFunTy . CoreUtils.exprType) expr
+ id <- Trans.lift $ mkInternalVar "param" arg_ty
+ change (Lam id (App expr (Var id)))
 -- Leave all other expressions unchanged
 eta c e = return e
 
@@ -375,7 +380,7 @@ funextract c expr@(App _ _) | is_var fexpr = do
     -- We could use is_applicable here instead of is_fun, but I think
     -- arguments to functions could only have forall typing when existential
     -- typing is enabled. Not sure, though.
-    doarg arg | not (is_simple arg) && is_fun arg = do
+    doarg arg | not (is_simple arg) && is_fun arg && not (has_free_tyvars arg) = do
       -- Create a new top level binding that binds the argument. Its body will
       -- be extended with lambda expressions, to take any free variables used
       -- by the argument expression.
@@ -405,15 +410,14 @@ funextract c expr = return expr
 -- Make sure the scrutinee of a case expression is a local variable
 -- reference.
 scrutsimpl :: Transform
--- Don't touch scrutinees that are already simple
-scrutsimpl c expr@(Case (Var _) _ _ _) = return expr
--- Replace all other cases with a let that binds the scrutinee and a new
+-- Replace a case expression with a let that binds the scrutinee and a new
 -- simple scrutinee, but only when the scrutinee is representable (to prevent
 -- loops with inlinenonrep, though I don't think a non-representable scrutinee
--- will be supported anyway...) 
+-- will be supported anyway...) and is not a local variable already.
 scrutsimpl c expr@(Case scrut b ty alts) = do
   repr <- isRepr scrut
-  if repr
+  local_var <- Trans.lift $ is_local_var scrut
+  if repr && not local_var
     then do
       id <- Trans.lift $ mkBinderFor scrut "scrut"
       change $ Let (NonRec id scrut) (Case (Var id) b ty alts)
@@ -748,7 +752,7 @@ inlinenonrepresult :: Transform
 -- that is fully applied (i.e., dos not have a function type) but is not
 -- representable. We apply in any context, since non-representable
 -- expressions are generally left alone and can occur anywhere.
-inlinenonrepresult context expr | not (is_fun expr) =
+inlinenonrepresult context expr | not (is_applicable expr) && not (has_free_tyvars expr) =
   case collectArgs expr of
     (Var f, args) | not (Id.isDictId f) -> do
       repr <- isRepr expr
@@ -816,6 +820,10 @@ inlinenonrepresult context expr | not (is_fun expr) =
 -- Leave all other expressions unchanged
 inlinenonrepresult c expr = return expr
 
+----------------------------------------------------------------
+-- Type-class transformations
+----------------------------------------------------------------
+
 --------------------------------
 -- ClassOp resolution
 --------------------------------