[project @ 2002-02-06 15:54:23 by simonpj]

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

diff --git a/ghc/compiler/coreSyn/CoreUtils.lhs b/ghc/compiler/coreSyn/CoreUtils.lhs
index a1a4694..d7a91a0 100644 (file)
--- a/ghc/compiler/coreSyn/CoreUtils.lhs
+++ b/ghc/compiler/coreSyn/CoreUtils.lhs
@@ -8,7 +8,7 @@ module CoreUtils (
        -- Construction
        mkNote, mkInlineMe, mkSCC, mkCoerce,
        bindNonRec, needsCaseBinding,
-       mkIfThenElse, mkAltExpr, mkPiType,
+       mkIfThenElse, mkAltExpr, mkPiType, mkPiTypes,
 
        -- Taking expressions apart
        findDefault, findAlt, hasDefault,
@@ -32,7 +32,7 @@ module CoreUtils (
        hashExpr,
 
        -- Equality
-       cheapEqExpr, eqExpr, applyTypeToArgs
+       cheapEqExpr, eqExpr, applyTypeToArgs, applyTypeToArg
     ) where
 
 #include "HsVersions.h"
@@ -57,9 +57,10 @@ import IdInfo                ( LBVarInfo(..),
                          megaSeqIdInfo )
 import NewDemand       ( appIsBottom )
 import Type            ( Type, mkFunTy, mkForAllTy, splitFunTy_maybe, splitFunTy,
-                         applyTys, isUnLiftedType, seqType, mkUTy, mkTyVarTy,
+                         applyTys, isUnLiftedType, seqType, mkTyVarTy,
                          splitForAllTy_maybe, isForAllTy, splitNewType_maybe, 
-                         splitTyConApp_maybe, eqType, funResultTy, applyTy
+                         splitTyConApp_maybe, eqType, funResultTy, applyTy,
+                         funResultTy, applyTy
                        )
 import TyCon           ( tyConArity )
 import TysWiredIn      ( boolTy, trueDataCon, falseDataCon )
@@ -104,26 +105,35 @@ lbvarinfo field to figure out the right annotation for the arrove in
 case of a term variable.
 
 \begin{code}
-mkPiType :: Var -> Type -> Type                -- The more polymorphic version doesn't work...
-mkPiType v ty | isId v    = (case idLBVarInfo v of
-                               LBVarInfo u -> mkUTy u
-                               otherwise   -> id) $
-                            mkFunTy (idType v) ty
-             | isTyVar v = mkForAllTy v ty
+mkPiType  :: Var   -> Type -> Type     -- The more polymorphic version
+mkPiTypes :: [Var] -> Type -> Type     --    doesn't work...
+
+mkPiTypes vs ty = foldr mkPiType ty vs
+
+mkPiType v ty
+   | isId v    = mkFunTy (idType v) ty
+   | otherwise = mkForAllTy v ty
 \end{code}
 
 \begin{code}
--- The first argument is just for debugging
+applyTypeToArg :: Type -> CoreExpr -> Type
+applyTypeToArg fun_ty (Type arg_ty) = applyTy fun_ty arg_ty
+applyTypeToArg fun_ty other_arg     = funResultTy fun_ty
+
 applyTypeToArgs :: CoreExpr -> Type -> [CoreExpr] -> Type
+-- A more efficient version of applyTypeToArg 
+-- when we have several args
+-- The first argument is just for debugging
 applyTypeToArgs e op_ty [] = op_ty
 
 applyTypeToArgs e op_ty (Type ty : args)
   =    -- Accumulate type arguments so we can instantiate all at once
-    applyTypeToArgs e (applyTys op_ty tys) rest_args
+    go [ty] args
   where
-    (tys, rest_args)        = go [ty] args
-    go tys (Type ty : args) = go (ty:tys) args
-    go tys rest_args       = (reverse tys, rest_args)
+    go rev_tys (Type ty : args) = go (ty:rev_tys) args
+    go rev_tys rest_args        = applyTypeToArgs e op_ty' rest_args
+                               where
+                                 op_ty' = applyTys op_ty (reverse rev_tys)
 
 applyTypeToArgs e op_ty (other_arg : args)
   = case (splitFunTy_maybe op_ty) of
@@ -907,7 +917,6 @@ exprArity e = go e
              go _                         = 0
 \end{code}
 
-
 %************************************************************************
 %*                                                                     *
 \subsection{Equality}
@@ -1006,7 +1015,7 @@ coreBindsSize bs = foldr ((+) . bindSize) 0 bs
 exprSize :: CoreExpr -> Int
        -- A measure of the size of the expressions
        -- It also forces the expression pretty drastically as a side effect
-exprSize (Var v)       = varSize v 
+exprSize (Var v)       = v `seq` 1
 exprSize (Lit lit)     = lit `seq` 1
 exprSize (App f a)     = exprSize f + exprSize a
 exprSize (Lam b e)     = varSize b + exprSize e