X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Futils%2FFiniteMap.lhs;h=3acadf137c24e0ace151450c8368a25edeb4c91a;hp=c14b77eb2afc099c864a865f296d6b3f1b44ff6d;hb=8133a9f47b99f4e65ed30551de32ad72c6b61b27;hpb=21a85c38819cfc951c6c8b440d9ea74f3fa02d55

diff --git a/compiler/utils/FiniteMap.lhs b/compiler/utils/FiniteMap.lhs
index c14b77e..3acadf1 100644
--- a/compiler/utils/FiniteMap.lhs
+++ b/compiler/utils/FiniteMap.lhs
@@ -1,762 +1,35 @@
-%
-% (c) The University of Glasgow 2006
-% (c) The AQUA Project, Glasgow University, 1994-1998
-%
-
-``Finite maps'' are the heart of the compiler's
-lookup-tables/environments and its implementation of sets.  Important
-stuff!
-
-This code is derived from that in the paper:
-\begin{display}
-S Adams
-"Efficient sets: a balancing act"
-Journal of functional programming 3(4) Oct 1993, pp553-562
-\end{display}
-
-The code is SPECIALIZEd to various highly-desirable types (e.g., Id)
-near the end.
 
 \begin{code}
-{-# OPTIONS -w #-}
--- The above warning supression flag is a temporary kludge.
--- While working on this module you are encouraged to remove it and fix
--- any warnings in the module. See
---     http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
--- for details
-
 module FiniteMap (
-        FiniteMap, -- abstract type
-
-        emptyFM, unitFM, listToFM,
-
-        addToFM,
-        addToFM_C,
-        addListToFM,
-        addListToFM_C,
-        delFromFM,
-        delListFromFM,
-
-        plusFM,
-        plusFM_C,
-        minusFM,
-        foldFM,
-
-        intersectFM,
-        intersectFM_C,
-        mapFM, filterFM,
-
-        sizeFM, isEmptyFM, elemFM, lookupFM, lookupWithDefaultFM,
-
-        fmToList, keysFM, eltsFM,
-
-        bagToFM
+        insertList,
+        insertListWith,
+        deleteList,
+        foldRight, foldRightWithKey
     ) where
 
-#include "HsVersions.h"
+import Data.Map (Map)
+import qualified Data.Map as Map
 
-#if defined(DEBUG_FINITEMAPS)/* NB NB NB */
-#define OUTPUTABLE_key , Outputable key
-#else
-#define OUTPUTABLE_key {--}
-#endif
+insertList :: Ord key => [(key,elt)] -> Map key elt -> Map key elt
+insertList xs m = foldl (\m (k, v) -> Map.insert k v m) m xs
 
-import Maybes
-import Bag ( Bag, foldrBag )
-import Util
-import Outputable
+insertListWith :: Ord key
+               => (elt -> elt -> elt)
+               -> [(key,elt)]
+               -> Map key elt
+               -> Map key elt
+insertListWith f xs m0 = foldl (\m (k, v) -> Map.insertWith f k v m) m0 xs
 
-#if 0
-import GHC.Exts
--- was this import only needed for I#, or does it have something
--- to do with the (not-presently-used) IF_NCG also?
-#endif
+deleteList :: Ord key => [key] -> Map key elt -> Map key elt
+deleteList ks m = foldl (flip Map.delete) m ks
 
-import Data.List
-
-#if 0
-#if ! OMIT_NATIVE_CODEGEN
-#  define IF_NCG(a) a
+foldRight        :: (elt -> a -> a) -> a -> Map key elt -> a
+foldRight        = Map.fold
+foldRightWithKey :: (key -> elt -> a -> a) -> a -> Map key elt -> a
+#if (MIN_VERSION_containers(0,4,0))
+foldRightWithKey = Map.foldrWithKey
 #else
-#  define IF_NCG(a) {--}
-#endif
+foldRightWithKey = Map.foldWithKey
 #endif
 \end{code}
 
-
-%************************************************************************
-%*                                                                      *
-\subsection{The signature of the module}
-%*                                                                      *
-%************************************************************************
-
-\begin{code}
--- BUILDING
-emptyFM     :: FiniteMap key elt
-unitFM      :: key -> elt -> FiniteMap key elt
--- In the case of duplicates, the last is taken:
-listToFM    :: (Ord key OUTPUTABLE_key) => [(key,elt)] -> FiniteMap key elt
--- In the case of duplicates, who knows which is taken:
-bagToFM     :: (Ord key OUTPUTABLE_key) => Bag (key,elt) -> FiniteMap key elt
-
--- ADDING AND DELETING
--- Throws away any previous binding
--- In the list case, the items are added starting with the
--- first one in the list
-addToFM     :: (Ord key OUTPUTABLE_key)
-            => FiniteMap key elt -> key -> elt -> FiniteMap key elt
-addListToFM :: (Ord key OUTPUTABLE_key)
-            => FiniteMap key elt -> [(key,elt)] -> FiniteMap key elt
-
--- Combines with previous binding
--- The combining fn goes (old -> new -> new)
-addToFM_C       :: (Ord key OUTPUTABLE_key) => (elt -> elt -> elt)
-                           -> FiniteMap key elt -> key -> elt
-                           -> FiniteMap key elt
-addListToFM_C   :: (Ord key OUTPUTABLE_key) => (elt -> elt -> elt)
-                           -> FiniteMap key elt -> [(key,elt)]
-                           -> FiniteMap key elt
-
--- Deletion doesn't complain if you try to delete something which isn't there
-delFromFM       :: (Ord key OUTPUTABLE_key)
-                => FiniteMap key elt -> key   -> FiniteMap key elt
-delListFromFM   :: (Ord key OUTPUTABLE_key)
-                => FiniteMap key elt -> [key] -> FiniteMap key elt
-
--- COMBINING
--- Bindings in right argument shadow those in the left
-plusFM          :: (Ord key OUTPUTABLE_key)
-                => FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt
-
--- Combines bindings for the same thing with the given function
-plusFM_C        :: (Ord key OUTPUTABLE_key)
-                => (elt -> elt -> elt)
-                -> FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt
-
--- (minusFM a1 a2) deletes from a1 any bindings which are bound in a2
-minusFM         :: (Ord key OUTPUTABLE_key)
-                => FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt
-
-intersectFM     :: (Ord key OUTPUTABLE_key)
-                => FiniteMap key elt -> FiniteMap key elt -> FiniteMap key elt
-intersectFM_C   :: (Ord key OUTPUTABLE_key)
-                => (elt1 -> elt2 -> elt3)
-                -> FiniteMap key elt1 -> FiniteMap key elt2
-                -> FiniteMap key elt3
-
--- MAPPING, FOLDING, FILTERING
-foldFM          :: (key -> elt -> a -> a) -> a -> FiniteMap key elt -> a
-mapFM           :: (key -> elt1 -> elt2)
-                -> FiniteMap key elt1 -> FiniteMap key elt2
-filterFM        :: (Ord key OUTPUTABLE_key)
-                => (key -> elt -> Bool)
-                -> FiniteMap key elt -> FiniteMap key elt
-
--- INTERROGATING
-sizeFM                  :: FiniteMap key elt -> Int
-isEmptyFM               :: FiniteMap key elt -> Bool
-
-elemFM                  :: (Ord key OUTPUTABLE_key)
-                        => key -> FiniteMap key elt -> Bool
-lookupFM                :: (Ord key OUTPUTABLE_key)
-                        => FiniteMap key elt -> key -> Maybe elt
--- lookupWithDefaultFM supplies a "default" elt
--- to return for an unmapped key
-lookupWithDefaultFM     :: (Ord key OUTPUTABLE_key)
-                        => FiniteMap key elt -> elt -> key -> elt
-
--- LISTIFYING
-fmToList        :: FiniteMap key elt -> [(key,elt)]
-keysFM          :: FiniteMap key elt -> [key]
-eltsFM          :: FiniteMap key elt -> [elt]
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{The @FiniteMap@ data type, and building of same}
-%*                                                                      *
-%************************************************************************
-
-Invariants about @FiniteMap@:
-\begin{enumerate}
-\item
-all keys in a FiniteMap are distinct
-\item
-all keys in left  subtree are $<$ key in Branch and
-all keys in right subtree are $>$ key in Branch
-\item
-size field of a Branch gives number of Branch nodes in the tree
-\item
-size of left subtree is differs from size of right subtree by a
-factor of at most \tr{sIZE_RATIO}
-\end{enumerate}
-
-\begin{code}
-data FiniteMap key elt
-  = EmptyFM
-  | Branch key elt        -- Key and elt stored here
-    {-# UNPACK #-} !Int   -- Size >= 1
-    (FiniteMap key elt)   -- Children
-    (FiniteMap key elt)
-\end{code}
-
-\begin{code}
-emptyFM = EmptyFM
-{-
-emptyFM
-  = Branch bottom bottom 0 bottom bottom
-  where
-    bottom = panic "emptyFM"
--}
-
---  #define EmptyFM (Branch _ _ 0 _ _)
-
-unitFM key elt = Branch key elt 1 emptyFM emptyFM
-
-listToFM = addListToFM emptyFM
-
-bagToFM = foldrBag (\(k,v) fm -> addToFM fm k v) emptyFM
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{Adding to and deleting from @FiniteMaps@}
-%*                                                                      *
-%************************************************************************
-
-\begin{code}
-addToFM fm key elt = addToFM_C (\ old new -> new) fm key elt
-
-addToFM_C combiner EmptyFM key elt = unitFM key elt
-addToFM_C combiner (Branch key elt size fm_l fm_r) new_key new_elt
-  = case compare new_key key of
-        LT -> mkBalBranch key elt (addToFM_C combiner fm_l new_key new_elt) fm_r
-        GT -> mkBalBranch key elt fm_l (addToFM_C combiner fm_r new_key new_elt)
-        EQ -> Branch new_key (combiner elt new_elt) size fm_l fm_r
-
-addListToFM fm key_elt_pairs = addListToFM_C (\ old new -> new) fm key_elt_pairs
-
-addListToFM_C combiner fm key_elt_pairs
-  = foldl' add fm key_elt_pairs	-- foldl adds from the left
-  where
-    add fmap (key,elt) = addToFM_C combiner fmap key elt
-\end{code}
-
-\begin{code}
-delFromFM EmptyFM del_key = emptyFM
-delFromFM (Branch key elt size fm_l fm_r) del_key
-  = case compare del_key key of
-        GT -> mkBalBranch key elt fm_l (delFromFM fm_r del_key)
-        LT -> mkBalBranch key elt (delFromFM fm_l del_key) fm_r
-        EQ -> glueBal fm_l fm_r
-
-delListFromFM fm keys = foldl' delFromFM fm keys
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{Combining @FiniteMaps@}
-%*                                                                      *
-%************************************************************************
-
-\begin{code}
-plusFM_C combiner EmptyFM fm2 = fm2
-plusFM_C combiner fm1 EmptyFM = fm1
-plusFM_C combiner fm1 (Branch split_key elt2 _ left right)
-  = mkVBalBranch split_key new_elt
-                 (plusFM_C combiner lts left)
-                 (plusFM_C combiner gts right)
-  where
-    lts     = splitLT fm1 split_key
-    gts     = splitGT fm1 split_key
-    new_elt = case lookupFM fm1 split_key of
-                Nothing   -> elt2
-                Just elt1 -> combiner elt1 elt2
-
--- It's worth doing plusFM specially, because we don't need
--- to do the lookup in fm1.
--- FM2 over-rides FM1.
-
-plusFM EmptyFM fm2 = fm2
-plusFM fm1 EmptyFM = fm1
-plusFM fm1 (Branch split_key elt1 _ left right)
-  = mkVBalBranch split_key elt1 (plusFM lts left) (plusFM gts right)
-  where
-    lts     = splitLT fm1 split_key
-    gts     = splitGT fm1 split_key
-
-minusFM EmptyFM fm2 = emptyFM
-minusFM fm1 EmptyFM = fm1
-minusFM fm1 (Branch split_key elt _ left right)
-  = glueVBal (minusFM lts left) (minusFM gts right)
-    -- The two can be way different, so we need glueVBal
-  where
-    lts = splitLT fm1 split_key -- NB gt and lt, so the equal ones
-    gts = splitGT fm1 split_key -- are not in either.
-
-intersectFM fm1 fm2 = intersectFM_C (\ left right -> right) fm1 fm2
-
-intersectFM_C combiner fm1 EmptyFM = emptyFM
-intersectFM_C combiner EmptyFM fm2 = emptyFM
-intersectFM_C combiner fm1 (Branch split_key elt2 _ left right)
-
-  | maybeToBool maybe_elt1 -- split_elt *is* in intersection
-  = mkVBalBranch split_key (combiner elt1 elt2)
-                 (intersectFM_C combiner lts left)
-                 (intersectFM_C combiner gts right)
-
-  | otherwise -- split_elt is *not* in intersection
-  = glueVBal (intersectFM_C combiner lts left)
-             (intersectFM_C combiner gts right)
-
-  where
-    lts = splitLT fm1 split_key -- NB gt and lt, so the equal ones
-    gts = splitGT fm1 split_key -- are not in either.
-
-    maybe_elt1 = lookupFM fm1 split_key
-    Just elt1  = maybe_elt1
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{Mapping, folding, and filtering with @FiniteMaps@}
-%*                                                                      *
-%************************************************************************
-
-\begin{code}
-foldFM k z EmptyFM = z
-foldFM k z (Branch key elt _ fm_l fm_r)
-  = foldFM k (k key elt (foldFM k z fm_r)) fm_l
-
-mapFM f EmptyFM = emptyFM
-mapFM f (Branch key elt size fm_l fm_r)
-  = Branch key (f key elt) size (mapFM f fm_l) (mapFM f fm_r)
-
-filterFM p EmptyFM = emptyFM
-filterFM p (Branch key elt _ fm_l fm_r)
-  | p key elt -- Keep the item
-  = mkVBalBranch key elt (filterFM p fm_l) (filterFM p fm_r)
-
-  | otherwise -- Drop the item
-  = glueVBal (filterFM p fm_l) (filterFM p fm_r)
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{Interrogating @FiniteMaps@}
-%*                                                                      *
-%************************************************************************
-
-\begin{code}
---{-# INLINE sizeFM #-}
-sizeFM EmptyFM               = 0
-sizeFM (Branch _ _ size _ _) = size
-
-isEmptyFM fm = sizeFM fm == 0
-
-lookupFM EmptyFM key = Nothing
-lookupFM (Branch key elt _ fm_l fm_r) key_to_find
-  = case compare key_to_find key of
-        LT -> lookupFM fm_l key_to_find
-        GT -> lookupFM fm_r key_to_find
-        EQ -> Just elt
-
-key `elemFM` fm
-  = case (lookupFM fm key) of { Nothing -> False; Just elt -> True }
-
-lookupWithDefaultFM fm deflt key
-  = case (lookupFM fm key) of { Nothing -> deflt; Just elt -> elt }
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{Listifying @FiniteMaps@}
-%*                                                                      *
-%************************************************************************
-
-\begin{code}
-fmToList fm = foldFM (\ key elt rest -> (key,elt) : rest) [] fm
-keysFM fm   = foldFM (\ key elt rest -> key : rest)       [] fm
-eltsFM fm   = foldFM (\ key elt rest -> elt : rest)       [] fm
-\end{code}
-
-
-%************************************************************************
-%*                                                                      *
-\subsection{The implementation of balancing}
-%*                                                                      *
-%************************************************************************
-
-%************************************************************************
-%*                                                                      *
-\subsubsection{Basic construction of a @FiniteMap@}
-%*                                                                      *
-%************************************************************************
-
-@mkBranch@ simply gets the size component right.  This is the ONLY
-(non-trivial) place the Branch object is built, so the ASSERTion
-recursively checks consistency.  (The trivial use of Branch is in
-@unitFM@.)
-
-\begin{code}
-sIZE_RATIO :: Int
-sIZE_RATIO = 5
-
-mkBranch :: (Ord key OUTPUTABLE_key) -- Used for the assertion checking only
-         => Int
-         -> key -> elt
-         -> FiniteMap key elt -> FiniteMap key elt
-         -> FiniteMap key elt
-
-mkBranch which key elt fm_l fm_r
-  = --ASSERT( left_ok && right_ok && balance_ok )
-#if defined(DEBUG_FINITEMAPS)
-    if not ( left_ok && right_ok && balance_ok ) then
-        pprPanic ("mkBranch:"++show which)
-                 (vcat [ppr [left_ok, right_ok, balance_ok],
-                            ppr key,
-                            ppr fm_l,
-                            ppr fm_r])
-    else
-#endif
-    let
-        result = Branch key elt (1 + left_size + right_size) fm_l fm_r
-    in
---    if sizeFM result <= 8 then
-        result
---    else
---      pprTrace ("mkBranch:"++(show which)) (ppr result) (
---      result
---      )
-  where
-    left_ok  = case fm_l of
-                EmptyFM                  -> True
-                Branch left_key _ _ _ _  -> let
-                                                biggest_left_key = fst (findMax fm_l)
-                                            in
-                                            biggest_left_key < key
-    right_ok = case fm_r of
-                EmptyFM                  -> True
-                Branch right_key _ _ _ _ -> let
-                                                smallest_right_key = fst (findMin fm_r)
-                                            in
-                                            key < smallest_right_key
-    balance_ok = True -- sigh
-{- LATER:
-    balance_ok
-      = -- Both subtrees have one or no elements...
-        (left_size + right_size <= 1)
--- NO         || left_size == 0  -- ???
--- NO         || right_size == 0 -- ???
-        -- ... or the number of elements in a subtree does not exceed
-        -- sIZE_RATIO times the number of elements in the other subtree
-      || (left_size  * sIZE_RATIO >= right_size &&
-          right_size * sIZE_RATIO >= left_size)
--}
-
-    left_size  = sizeFM fm_l
-    right_size = sizeFM fm_r
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsubsection{{\em Balanced} construction of a @FiniteMap@}
-%*                                                                      *
-%************************************************************************
-
-@mkBalBranch@ rebalances, assuming that the subtrees aren't too far
-out of whack.
-
-\begin{code}
-mkBalBranch :: (Ord key OUTPUTABLE_key)
-            => key -> elt
-            -> FiniteMap key elt -> FiniteMap key elt
-            -> FiniteMap key elt
-
-mkBalBranch key elt fm_L fm_R
-
-  | size_l + size_r < 2
-  = mkBranch 1{-which-} key elt fm_L fm_R
-
-  | size_r > sIZE_RATIO * size_l -- Right tree too big
-  = case fm_R of
-        Branch _ _ _ fm_rl fm_rr
-                | sizeFM fm_rl < 2 * sizeFM fm_rr -> single_L fm_L fm_R
-                | otherwise                       -> double_L fm_L fm_R
-        -- Other case impossible
-
-  | size_l > sIZE_RATIO * size_r -- Left tree too big
-  = case fm_L of
-        Branch _ _ _ fm_ll fm_lr
-                | sizeFM fm_lr < 2 * sizeFM fm_ll -> single_R fm_L fm_R
-                | otherwise                       -> double_R fm_L fm_R
-        -- Other case impossible
-
-  | otherwise -- No imbalance
-  = mkBranch 2{-which-} key elt fm_L fm_R
-
-  where
-    size_l   = sizeFM fm_L
-    size_r   = sizeFM fm_R
-
-    single_L fm_l (Branch key_r elt_r _ fm_rl fm_rr)
-        = mkBranch 3{-which-} key_r elt_r (mkBranch 4{-which-} key elt fm_l fm_rl) fm_rr
-
-    double_L fm_l (Branch key_r elt_r _ (Branch key_rl elt_rl _ fm_rll fm_rlr) fm_rr)
-        = mkBranch 5{-which-} key_rl elt_rl
-                   (mkBranch 6{-which-} key   elt   fm_l   fm_rll)
-                   (mkBranch 7{-which-} key_r elt_r fm_rlr fm_rr)
-
-    single_R (Branch key_l elt_l _ fm_ll fm_lr) fm_r
-        = mkBranch 8{-which-} key_l elt_l fm_ll
-                   (mkBranch 9{-which-} key elt fm_lr fm_r)
-
-    double_R (Branch key_l elt_l _ fm_ll (Branch key_lr elt_lr _ fm_lrl fm_lrr)) fm_r
-        = mkBranch 10{-which-} key_lr elt_lr
-                   (mkBranch 11{-which-} key_l elt_l fm_ll  fm_lrl)
-                   (mkBranch 12{-which-} key   elt   fm_lrr fm_r)
-\end{code}
-
-
-\begin{code}
-mkVBalBranch :: (Ord key OUTPUTABLE_key)
-             => key -> elt
-             -> FiniteMap key elt -> FiniteMap key elt
-             -> FiniteMap key elt
-
--- Assert: in any call to (mkVBalBranch_C comb key elt l r),
---         (a) all keys in l are < all keys in r
---         (b) all keys in l are < key
---         (c) all keys in r are > key
-
-mkVBalBranch key elt EmptyFM fm_r = addToFM fm_r key elt
-mkVBalBranch key elt fm_l EmptyFM = addToFM fm_l key elt
-
-mkVBalBranch key elt fm_l@(Branch key_l elt_l _ fm_ll fm_lr)
-                     fm_r@(Branch key_r elt_r _ fm_rl fm_rr)
-  | sIZE_RATIO * size_l < size_r
-  = mkBalBranch key_r elt_r (mkVBalBranch key elt fm_l fm_rl) fm_rr
-
-  | sIZE_RATIO * size_r < size_l
-  = mkBalBranch key_l elt_l fm_ll (mkVBalBranch key elt fm_lr fm_r)
-
-  | otherwise
-  = mkBranch 13{-which-} key elt fm_l fm_r
-
-  where
-    size_l = sizeFM fm_l
-    size_r = sizeFM fm_r
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsubsection{Gluing two trees together}
-%*                                                                      *
-%************************************************************************
-
-@glueBal@ assumes its two arguments aren't too far out of whack, just
-like @mkBalBranch@.  But: all keys in first arg are $<$ all keys in
-second.
-
-\begin{code}
-glueBal :: (Ord key OUTPUTABLE_key)
-        => FiniteMap key elt -> FiniteMap key elt
-        -> FiniteMap key elt
-
-glueBal EmptyFM fm2 = fm2
-glueBal fm1 EmptyFM = fm1
-glueBal fm1 fm2
-  -- The case analysis here (absent in Adams' program) is really to deal
-  -- with the case where fm2 is a singleton. Then deleting the minimum means
-  -- we pass an empty tree to mkBalBranch, which breaks its invariant.
-  | sizeFM fm2 > sizeFM fm1
-  = mkBalBranch mid_key2 mid_elt2 fm1 (deleteMin fm2)
-
-  | otherwise
-  = mkBalBranch mid_key1 mid_elt1 (deleteMax fm1) fm2
-  where
-    (mid_key1, mid_elt1) = findMax fm1
-    (mid_key2, mid_elt2) = findMin fm2
-\end{code}
-
-@glueVBal@ copes with arguments which can be of any size.
-But: all keys in first arg are $<$ all keys in second.
-
-\begin{code}
-glueVBal :: (Ord key OUTPUTABLE_key)
-         => FiniteMap key elt -> FiniteMap key elt
-         -> FiniteMap key elt
-
-glueVBal EmptyFM fm2 = fm2
-glueVBal fm1 EmptyFM = fm1
-glueVBal fm_l@(Branch key_l elt_l _ fm_ll fm_lr)
-         fm_r@(Branch key_r elt_r _ fm_rl fm_rr)
-  | sIZE_RATIO * size_l < size_r
-  = mkBalBranch key_r elt_r (glueVBal fm_l fm_rl) fm_rr
-
-  | sIZE_RATIO * size_r < size_l
-  = mkBalBranch key_l elt_l fm_ll (glueVBal fm_lr fm_r)
-
-  | otherwise -- We now need the same two cases as in glueBal above.
-  = glueBal fm_l fm_r
-  where
-    size_l = sizeFM fm_l
-    size_r = sizeFM fm_r
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{Local utilities}
-%*                                                                      *
-%************************************************************************
-
-\begin{code}
-splitLT, splitGT :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> key -> FiniteMap key elt
-
--- splitLT fm split_key  =  fm restricted to keys <  split_key
--- splitGT fm split_key  =  fm restricted to keys >  split_key
-
-splitLT EmptyFM split_key = emptyFM
-splitLT (Branch key elt _ fm_l fm_r) split_key
-  = case compare split_key key of
-        LT -> splitLT fm_l split_key
-        GT -> mkVBalBranch key elt fm_l (splitLT fm_r split_key)
-        EQ -> fm_l
-
-splitGT EmptyFM split_key = emptyFM
-splitGT (Branch key elt _ fm_l fm_r) split_key
-  = case compare split_key key of
-        GT -> splitGT fm_r split_key
-        LT -> mkVBalBranch key elt (splitGT fm_l split_key) fm_r
-        EQ -> fm_r
-
-findMin :: FiniteMap key elt -> (key,elt)
-findMin (Branch key elt _ EmptyFM _) = (key,elt)
-findMin (Branch key elt _ fm_l    _) = findMin fm_l
-
-deleteMin :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> FiniteMap key elt
-deleteMin (Branch key elt _ EmptyFM fm_r) = fm_r
-deleteMin (Branch key elt _ fm_l    fm_r) = mkBalBranch key elt (deleteMin fm_l) fm_r
-
-findMax :: FiniteMap key elt -> (key,elt)
-findMax (Branch key elt _ _ EmptyFM) = (key,elt)
-findMax (Branch key elt _ _    fm_r) = findMax fm_r
-
-deleteMax :: (Ord key OUTPUTABLE_key) => FiniteMap key elt -> FiniteMap key elt
-deleteMax (Branch key elt _ fm_l EmptyFM) = fm_l
-deleteMax (Branch key elt _ fm_l    fm_r) = mkBalBranch key elt fm_l (deleteMax fm_r)
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{Output-ery}
-%*                                                                      *
-%************************************************************************
-
-\begin{code}
-#if defined(DEBUG_FINITEMAPS)
-
-instance (Outputable key) => Outputable (FiniteMap key elt) where
-    ppr fm = pprX fm
-
-pprX EmptyFM = char '!'
-pprX (Branch key elt sz fm_l fm_r)
- = parens (hcat [pprX fm_l, space,
-                 ppr key, space, int sz, space,
-                 pprX fm_r])
-#else
--- and when not debugging the package itself...
-instance (Outputable key, Outputable elt) => Outputable (FiniteMap key elt) where
-    ppr fm = ppr (fmToList fm)
-#endif
-
-#if 0
-instance (Eq key, Eq elt) => Eq (FiniteMap key elt) where
-  fm_1 == fm_2 = (sizeFM   fm_1 == sizeFM   fm_2) &&   -- quick test
-                 (fmToList fm_1 == fmToList fm_2)
-
-{- NO: not clear what The Right Thing to do is:
-instance (Ord key, Ord elt) => Ord (FiniteMap key elt) where
-  fm_1 <= fm_2 = (sizeFM   fm_1 <= sizeFM   fm_2) &&   -- quick test
-                 (fmToList fm_1 <= fmToList fm_2)
--}
-#endif
-\end{code}
-
-%************************************************************************
-%*                                                                      *
-\subsection{Efficiency pragmas for GHC}
-%*                                                                      *
-%************************************************************************
-
-When the FiniteMap module is used in GHC, we specialise it for
-\tr{Uniques}, for dastardly efficiency reasons.
-
-\begin{code}
-#if 0
-
-#ifdef __GLASGOW_HASKELL__
-
-{-# SPECIALIZE addListToFM
-                :: FiniteMap (FastString, FAST_STRING) elt -> [((FAST_STRING, FAST_STRING),elt)] -> FiniteMap (FAST_STRING, FAST_STRING) elt
-                 , FiniteMap RdrName elt -> [(RdrName,elt)] -> FiniteMap RdrName elt
-    IF_NCG(COMMA   FiniteMap Reg elt -> [(Reg COMMA elt)] -> FiniteMap Reg elt)
-    #-}
-{-# SPECIALIZE addListToFM_C
-                :: (elt -> elt -> elt) -> FiniteMap TyCon elt -> [(TyCon,elt)] -> FiniteMap TyCon elt
-                 , (elt -> elt -> elt) -> FiniteMap FastString elt -> [(FAST_STRING,elt)] -> FiniteMap FAST_STRING elt
-    IF_NCG(COMMA   (elt -> elt -> elt) -> FiniteMap Reg elt -> [(Reg COMMA elt)] -> FiniteMap Reg elt)
-    #-}
-{-# SPECIALIZE addToFM
-                :: FiniteMap CLabel elt -> CLabel -> elt  -> FiniteMap CLabel elt
-                 , FiniteMap FastString elt -> FAST_STRING -> elt  -> FiniteMap FAST_STRING elt
-                 , FiniteMap (FastString, FAST_STRING) elt -> (FAST_STRING, FAST_STRING) -> elt  -> FiniteMap (FAST_STRING, FAST_STRING) elt
-                 , FiniteMap RdrName elt -> RdrName -> elt  -> FiniteMap RdrName elt
-    IF_NCG(COMMA   FiniteMap Reg elt -> Reg -> elt  -> FiniteMap Reg elt)
-    #-}
-{-# SPECIALIZE addToFM_C
-                :: (elt -> elt -> elt) -> FiniteMap (RdrName, RdrName) elt -> (RdrName, RdrName) -> elt -> FiniteMap (RdrName, RdrName) elt
-                 , (elt -> elt -> elt) -> FiniteMap FastString elt -> FAST_STRING -> elt -> FiniteMap FAST_STRING elt
-    IF_NCG(COMMA   (elt -> elt -> elt) -> FiniteMap Reg elt -> Reg -> elt -> FiniteMap Reg elt)
-    #-}
-{-# SPECIALIZE bagToFM
-                :: Bag (FastString,elt) -> FiniteMap FAST_STRING elt
-    #-}
-{-# SPECIALIZE delListFromFM
-                :: FiniteMap RdrName elt -> [RdrName]   -> FiniteMap RdrName elt
-                 , FiniteMap FastString elt -> [FAST_STRING]   -> FiniteMap FAST_STRING elt
-    IF_NCG(COMMA   FiniteMap Reg elt -> [Reg]   -> FiniteMap Reg elt)
-    #-}
-{-# SPECIALIZE listToFM
-                :: [([Char],elt)] -> FiniteMap [Char] elt
-                 , [(FastString,elt)] -> FiniteMap FAST_STRING elt
-                 , [((FastString,FAST_STRING),elt)] -> FiniteMap (FAST_STRING, FAST_STRING) elt
-    IF_NCG(COMMA   [(Reg COMMA elt)] -> FiniteMap Reg elt)
-    #-}
-{-# SPECIALIZE lookupFM
-                :: FiniteMap CLabel elt -> CLabel -> Maybe elt
-                 , FiniteMap [Char] elt -> [Char] -> Maybe elt
-                 , FiniteMap FastString elt -> FAST_STRING -> Maybe elt
-                 , FiniteMap (FastString,FAST_STRING) elt -> (FAST_STRING,FAST_STRING) -> Maybe elt
-                 , FiniteMap RdrName elt -> RdrName -> Maybe elt
-                 , FiniteMap (RdrName,RdrName) elt -> (RdrName,RdrName) -> Maybe elt
-    IF_NCG(COMMA   FiniteMap Reg elt -> Reg -> Maybe elt)
-    #-}
-{-# SPECIALIZE lookupWithDefaultFM
-                :: FiniteMap FastString elt -> elt -> FAST_STRING -> elt
-    IF_NCG(COMMA   FiniteMap Reg elt -> elt -> Reg -> elt)
-    #-}
-{-# SPECIALIZE plusFM
-                :: FiniteMap RdrName elt -> FiniteMap RdrName elt -> FiniteMap RdrName elt
-                 , FiniteMap FastString elt -> FiniteMap FAST_STRING elt -> FiniteMap FAST_STRING elt
-    IF_NCG(COMMA   FiniteMap Reg elt -> FiniteMap Reg elt -> FiniteMap Reg elt)
-    #-}
-{-# SPECIALIZE plusFM_C
-                :: (elt -> elt -> elt) -> FiniteMap FastString elt -> FiniteMap FAST_STRING elt -> FiniteMap FAST_STRING elt
-    IF_NCG(COMMA   (elt -> elt -> elt) -> FiniteMap Reg elt -> FiniteMap Reg elt -> FiniteMap Reg elt)
-    #-}
-
-#endif /* compiling with ghc and have specialiser */
-
-#endif /* 0 */
-\end{code}