Add a simple arity analyser

[ghc-hetmet.git] / compiler / coreSyn / CoreUtils.lhs

diff --git a/compiler/coreSyn/CoreUtils.lhs b/compiler/coreSyn/CoreUtils.lhs
index 72977be..3b7f1af 100644 (file)
--- a/compiler/coreSyn/CoreUtils.lhs
+++ b/compiler/coreSyn/CoreUtils.lhs
@@ -25,7 +25,8 @@ module CoreUtils (
 
        -- * Properties of expressions
        exprType, coreAltType, coreAltsType,
-       exprIsDupable, exprIsTrivial, exprIsCheap, exprIsExpandable,
+       exprIsDupable, exprIsTrivial, 
+        exprIsCheap, exprIsExpandable, exprIsCheap', CheapAppFun,
        exprIsHNF, exprOkForSpeculation, exprIsBig, exprIsConLike,
        rhsIsStatic, isCheapApp, isExpandableApp,
 
@@ -513,8 +514,8 @@ exprIsCheap = exprIsCheap' isCheapApp
 exprIsExpandable :: CoreExpr -> Bool
 exprIsExpandable = exprIsCheap' isExpandableApp        -- See Note [CONLIKE pragma] in BasicTypes
 
-
-exprIsCheap' :: (Id -> Int -> Bool) -> CoreExpr -> Bool
+type CheapAppFun = Id -> Int -> Bool
+exprIsCheap' :: CheapAppFun -> CoreExpr -> Bool
 exprIsCheap' _          (Lit _)   = True
 exprIsCheap' _          (Type _)  = True
 exprIsCheap' _          (Var _)   = True
@@ -582,12 +583,12 @@ exprIsCheap' good_app other_expr  -- Applications and variables
                -- BUT: Take care with (sel d x)!  The (sel d) might be cheap, but
                --      there's no guarantee that (sel d x) will be too.  Hence (n_val_args == 1)
 
-isCheapApp :: Id -> Int -> Bool
+isCheapApp :: CheapAppFun
 isCheapApp fn n_val_args
   = isDataConWorkId fn 
   || n_val_args < idArity fn
 
-isExpandableApp :: Id -> Int -> Bool
+isExpandableApp :: CheapAppFun
 isExpandableApp fn n_val_args
   =  isConLikeId fn
   || n_val_args < idArity fn