X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FbasicTypes%2FUniqSupply.lhs;h=4f56474a52fe486066a5dc07e94ace0642a6b439;hb=6eca2acf184d4911123193757bdd38e53caa3467;hp=7c155f326cc4a41ac5d54457707eaefc5c435e44;hpb=f01a8e8c9c53bfb5ab3393ed3457ebf25390efa1;p=ghc-hetmet.git

diff --git a/ghc/compiler/basicTypes/UniqSupply.lhs b/ghc/compiler/basicTypes/UniqSupply.lhs
index 7c155f3..4f56474 100644
--- a/ghc/compiler/basicTypes/UniqSupply.lhs
+++ b/ghc/compiler/basicTypes/UniqSupply.lhs
@@ -1,32 +1,37 @@
 %
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
 %
 \section[UniqSupply]{The @UniqueSupply@ data type and a (monadic) supply thereof}
 
 \begin{code}
-#include "HsVersions.h"
-
 module UniqSupply (
 
 	UniqSupply,		-- Abstractly
 
-	getUnique, getUniques,	-- basic ops
+	uniqFromSupply, uniqsFromSupply,	-- basic ops
 
-	UniqSM(..),		-- type: unique supply monad
-	initUs, thenUs, returnUs,
+	UniqSM,		-- type: unique supply monad
+	initUs, initUs_, thenUs, thenUs_, returnUs, fixUs, getUs, setUs,
+	getUniqueUs, getUniquesUs,
 	mapUs, mapAndUnzipUs, mapAndUnzip3Us,
 	thenMaybeUs, mapAccumLUs,
+	lazyThenUs, lazyMapUs,
 
 	mkSplitUniqSupply,
 	splitUniqSupply
   ) where
 
-import Ubiq{-uitous-}
+#include "HsVersions.h"
 
 import Unique
-import Util
+import Panic	( panic )
 
-import PreludeGlaST
+import GlaExts
+
+#if __GLASGOW_HASKELL__ < 301
+import IOBase		( IO(..), IOResult(..) )
+#else
+#endif
 
 w2i x = word2Int# x
 i2w x = int2Word# x
@@ -62,51 +67,42 @@ data UniqSupply
 mkSplitUniqSupply :: Char -> IO UniqSupply
 
 splitUniqSupply :: UniqSupply -> (UniqSupply, UniqSupply)
-getUnique :: UniqSupply -> Unique
-getUniques :: Int -> UniqSupply -> [Unique]
+uniqFromSupply  :: UniqSupply -> Unique
+uniqsFromSupply :: Int -> UniqSupply -> [Unique]
 \end{code}
 
 \begin{code}
-mkSplitUniqSupply (MkChar c#)
+mkSplitUniqSupply (C# c#)
   = let
 	mask# = (i2w (ord# c#)) `shiftL#` (i2w_s 24#)
 
 	-- here comes THE MAGIC:
 
+	-- This is one of the most hammered bits in the whole compiler
 	mk_supply#
-	  = unsafe_interleave (
-		mk_unique   `thenPrimIO` \ uniq ->
-		mk_supply#  `thenPrimIO` \ s1 ->
-		mk_supply#  `thenPrimIO` \ s2 ->
-		returnPrimIO (MkSplitUniqSupply uniq s1 s2)
+	  = unsafeInterleaveIO (
+		mk_unique   >>= \ uniq ->
+		mk_supply#  >>= \ s1 ->
+		mk_supply#  >>= \ s2 ->
+		return (MkSplitUniqSupply uniq s1 s2)
 	    )
-	  where
-	    -- inlined copy of unsafeInterleavePrimIO;
-	    -- this is the single-most-hammered bit of code
-	    -- in the compiler....
-	    unsafe_interleave m s
-	      = let
-		    (r, new_s) = m s
-		in
-		(r, s)
-
-	mk_unique = _ccall_ genSymZh		`thenPrimIO` \ (W# u#) ->
-		    returnPrimIO (MkInt (w2i (mask# `or#` u#)))
+
+	mk_unique = _ccall_ genSymZh		>>= \ (W# u#) ->
+		    return (I# (w2i (mask# `or#` u#)))
     in
-    mk_supply#	`thenPrimIO` \ s ->
-    return s
+    mk_supply#
 
 splitUniqSupply (MkSplitUniqSupply _ s1 s2) = (s1, s2)
 \end{code}
 
 \begin{code}
-getUnique (MkSplitUniqSupply (MkInt n) _ _) = mkUniqueGrimily n
+uniqFromSupply (MkSplitUniqSupply (I# n) _ _) = mkUniqueGrimily n
 
-getUniques i@(MkInt i#) supply = i# `get_from` supply
+uniqsFromSupply (I# i) supply = i `get_from` supply
   where
     get_from 0# _ = []
-    get_from n# (MkSplitUniqSupply (MkInt u#) _ s2)
-      = mkUniqueGrimily u# : get_from (n# `minusInt#` 1#) s2
+    get_from n (MkSplitUniqSupply (I# u) _ s2)
+      = mkUniqueGrimily u : get_from (n -# 1#) s2
 \end{code}
 
 %************************************************************************
@@ -116,43 +112,73 @@ getUniques i@(MkInt i#) supply = i# `get_from` supply
 %************************************************************************
 
 \begin{code}
-type UniqSM result = UniqSupply -> result
-
--- the initUs function also returns the final UniqSupply
+type UniqSM result = UniqSupply -> (result, UniqSupply)
 
-initUs :: UniqSupply -> UniqSM a -> (UniqSupply, a)
+-- the initUs function also returns the final UniqSupply; initUs_ drops it
+initUs :: UniqSupply -> UniqSM a -> (a,UniqSupply)
+initUs init_us m = case m init_us of { (r,us) -> (r,us) }
 
-initUs init_us m
-  = case (splitUniqSupply init_us) of { (s1, s2) ->
-    (s2, m s1) }
+initUs_ :: UniqSupply -> UniqSM a -> a
+initUs_ init_us m = case m init_us of { (r,us) -> r }
 
 {-# INLINE thenUs #-}
+{-# INLINE lazyThenUs #-}
 {-# INLINE returnUs #-}
 {-# INLINE splitUniqSupply #-}
 \end{code}
 
 @thenUs@ is where we split the @UniqSupply@.
 \begin{code}
-thenUs :: UniqSM a -> (a -> UniqSM b) -> UniqSM b
+fixUs :: (a -> UniqSM a) -> UniqSM a
+fixUs m us
+  = (r,us')  where  (r,us') = m r us
 
+thenUs :: UniqSM a -> (a -> UniqSM b) -> UniqSM b
 thenUs expr cont us
-  = case (splitUniqSupply us) of { (s1, s2) ->
-    case (expr s1)	      of { result ->
-    cont result s2 }}
-\end{code}
+  = case (expr us) of { (result, us') -> cont result us' }
+
+lazyThenUs :: UniqSM a -> (a -> UniqSM b) -> UniqSM b
+lazyThenUs expr cont us
+  = let (result, us') = expr us in cont result us'
+
+thenUs_ :: UniqSM a -> UniqSM b -> UniqSM b
+thenUs_ expr cont us
+  = case (expr us) of { (_, us') -> cont us' }
+
 
-\begin{code}
 returnUs :: a -> UniqSM a
-returnUs result us = result
+returnUs result us = (result, us)
 
-mapUs :: (a -> UniqSM b) -> [a] -> UniqSM [b]
+getUs :: UniqSM UniqSupply
+getUs us = (us, panic "getUs: bad supply")
 
+setUs :: UniqSupply -> UniqSM ()
+setUs us old_us = ((), us)
+
+getUniqueUs :: UniqSM Unique
+getUniqueUs us = case splitUniqSupply us of
+		   (us1,us2) -> (uniqFromSupply us1, us2)
+
+getUniquesUs :: Int -> UniqSM [Unique]
+getUniquesUs n us = case splitUniqSupply us of
+		      (us1,us2) -> (uniqsFromSupply n us1, us2)
+\end{code}
+
+\begin{code}
+mapUs :: (a -> UniqSM b) -> [a] -> UniqSM [b]
 mapUs f []     = returnUs []
 mapUs f (x:xs)
   = f x         `thenUs` \ r  ->
     mapUs f xs  `thenUs` \ rs ->
     returnUs (r:rs)
 
+lazyMapUs :: (a -> UniqSM b) -> [a] -> UniqSM [b]
+lazyMapUs f []     = returnUs []
+lazyMapUs f (x:xs)
+  = f x             `lazyThenUs` \ r  ->
+    lazyMapUs f xs  `lazyThenUs` \ rs ->
+    returnUs (r:rs)
+
 mapAndUnzipUs  :: (a -> UniqSM (b,c))   -> [a] -> UniqSM ([b],[c])
 mapAndUnzip3Us :: (a -> UniqSM (b,c,d)) -> [a] -> UniqSM ([b],[c],[d])