X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FbasicTypes%2FUniqSupply.lhs;h=4b83b52a610b005ae6a2330af0b9a327e07326a1;hb=bc86223d8822da6949334ddb8b9040cf65637b4a;hp=3cb2ca724e4664f1970cb98a56e6d96640cbbc09;hpb=5eb1c77c795f92ed0f4c8023847e9d4be1a4fd0d;p=ghc-hetmet.git

diff --git a/ghc/compiler/basicTypes/UniqSupply.lhs b/ghc/compiler/basicTypes/UniqSupply.lhs
index 3cb2ca7..4b83b52 100644
--- a/ghc/compiler/basicTypes/UniqSupply.lhs
+++ b/ghc/compiler/basicTypes/UniqSupply.lhs
@@ -4,16 +4,14 @@
 \section[UniqSupply]{The @UniqueSupply@ data type and a (monadic) supply thereof}
 
 \begin{code}
-#include "HsVersions.h"
-
 module UniqSupply (
 
 	UniqSupply,		-- Abstractly
 
 	getUnique, getUniques,	-- basic ops
 
-	SYN_IE(UniqSM),		-- type: unique supply monad
-	initUs, thenUs, returnUs,
+	UniqSM,		-- type: unique supply monad
+	initUs, thenUs, returnUs, fixUs,
 	mapUs, mapAndUnzipUs, mapAndUnzip3Us,
 	thenMaybeUs, mapAccumLUs,
 
@@ -21,17 +19,16 @@ module UniqSupply (
 	splitUniqSupply
   ) where
 
-IMP_Ubiq(){-uitous-}
+#include "HsVersions.h"
 
 import Unique
 import Util
 
-import PreludeGlaST
+import GlaExts
 
-#if __GLASGOW_HASKELL__ >= 200
-# define WHASH	    GHCbase.W#
+#if __GLASGOW_HASKELL__ < 301
+import IOBase		( IO(..), IOResult(..) )
 #else
-# define WHASH	    W#
 #endif
 
 w2i x = word2Int# x
@@ -79,36 +76,19 @@ mkSplitUniqSupply (C# c#)
 
 	-- here comes THE MAGIC:
 
+	-- This is one of the most hammered bits in the whole compiler
 	mk_supply#
-	  = unsafeInterleavePrimIO {-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....
-	    -- Too bad it's not 1.3-portable...
-	    unsafe_interleave m s
-	      = let
-		    (r, new_s) = m s
-		in
-		(r, s)
--}
-
-	mk_unique = _ccall_ genSymZh		`thenPrimIO` \ (WHASH u#) ->
-		    returnPrimIO (I# (w2i (mask# `or#` u#)))
+
+	mk_unique = _ccall_ genSymZh		>>= \ (W# u#) ->
+		    return (I# (w2i (mask# `or#` u#)))
     in
-#if __GLASGOW_HASKELL__ >= 200
-    primIOToIO mk_supply#	>>= \ s ->
-    return s
-#else
-    mk_supply#	`thenPrimIO` \ s ->
-    return s
-#endif
+    mk_supply#
 
 splitUniqSupply (MkSplitUniqSupply _ s1 s2) = (s1, s2)
 \end{code}
@@ -120,7 +100,7 @@ getUniques (I# i) supply = i `get_from` supply
   where
     get_from 0# _ = []
     get_from n (MkSplitUniqSupply (I# u) _ s2)
-      = mkUniqueGrimily u : get_from (n `minusInt#` 1#) s2
+      = mkUniqueGrimily u : get_from (n -# 1#) s2
 \end{code}
 
 %************************************************************************
@@ -134,11 +114,9 @@ type UniqSM result = UniqSupply -> result
 
 -- the initUs function also returns the final UniqSupply
 
-initUs :: UniqSupply -> UniqSM a -> (UniqSupply, a)
+initUs :: UniqSupply -> UniqSM a -> a
 
-initUs init_us m
-  = case (splitUniqSupply init_us) of { (s1, s2) ->
-    (s2, m s1) }
+initUs init_us m = m init_us
 
 {-# INLINE thenUs #-}
 {-# INLINE returnUs #-}
@@ -147,6 +125,10 @@ initUs init_us m
 
 @thenUs@ is where we split the @UniqSupply@.
 \begin{code}
+fixUs :: (a -> UniqSM a) -> UniqSM a
+fixUs m us
+  = r  where  r = m r us
+
 thenUs :: UniqSM a -> (a -> UniqSM b) -> UniqSM b
 
 thenUs expr cont us