[commit: dph] master: Fix reverse example (c223c04)

[Ben Lippmeier]

Repository : ssh://darcs.haskell.org//srv/darcs/packages/dph

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/c223c04920bbd45d82d0943dd958c4e59224a627

>---------------------------------------------------------------

commit c223c04920bbd45d82d0943dd958c4e59224a627
Author: Ben Lippmeier <benl at ouroborus.net>
Date:   Thu Apr 14 15:42:09 2011 +1000

    Fix reverse example

>---------------------------------------------------------------

 dph-examples/broken/Reverse/dph/ReverseVector.hs   |   21 -------
 .../broken/Reverse/dph/ReverseVectorised.hs        |   30 -----------
 dph-examples/imaginary/Reverse/dph/Main.hs         |   56 ++++++++++++++++++++
 .../imaginary/Reverse/dph/ReverseVector.hs         |   21 +++++++
 .../imaginary/Reverse/dph/ReverseVectorised.hs     |   29 ++++++++++
 5 files changed, 106 insertions(+), 51 deletions(-)

diff --git a/dph-examples/broken/Reverse/dph/ReverseVector.hs b/dph-examples/broken/Reverse/dph/ReverseVector.hs
deleted file mode 100644
index 42a10b4..0000000
--- a/dph-examples/broken/Reverse/dph/ReverseVector.hs
+++ /dev/null
@@ -1,21 +0,0 @@
-
-module ReverseVector
-	(treeReverse)
-where
-import qualified Data.Vector.Unboxed as V
-import Data.Vector.Unboxed		(Vector)
-
--- | Reverse the elements in an array using a tree.
-treeReverse :: Vector Double -> Vector Double
-{-# NOINLINE treeReverse #-}
-treeReverse xx
-	| V.length xx == 1
-	= xx
-	
-	| otherwise
-	= let	len	= V.length xx
-		half	= len `div` 2
-		s1	= V.slice 0    half  xx
-		s2	= V.slice half half  xx		
-	  in	treeReverse s2 V.++ treeReverse s1
-
diff --git a/dph-examples/broken/Reverse/dph/ReverseVectorised.hs b/dph-examples/broken/Reverse/dph/ReverseVectorised.hs
deleted file mode 100644
index 2a3f97b..0000000
--- a/dph-examples/broken/Reverse/dph/ReverseVectorised.hs
+++ /dev/null
@@ -1,30 +0,0 @@
-{-# LANGUAGE ParallelArrays #-}
-{-# OPTIONS -fvectorise #-}
-module ReverseVectorised	
-	(treeReversePA)
-where
-import Data.Array.Parallel.Prelude
-import Data.Array.Parallel.Prelude.Double
-import qualified Data.Array.Parallel.Prelude.Int as Int
-import qualified Prelude as P
-
-
-treeReversePA :: PArray Double -> PArray Double
-{-# NOINLINE treeReversePA #-}
-treeReversePA ps
-	= toPArrayP (treeReverse (fromPArrayP ps))
-
-
--- | Reverse the elements in an array using a tree.
-treeReverse :: [:Double:] -> [:Double:]
-{-# NOINLINE treeReverse #-}
-treeReverse xx
-	| lengthP xx Int.== 1
-	= xx
-	
-	| otherwise
-	= let	len	= lengthP xx
-		half	= len `Int.div` 2
-		s1	= sliceP 0    half xx
-		s2	= sliceP half half xx		
-	  in	concatP (mapP treeReverse [:s1, s2:])
diff --git a/dph-examples/imaginary/Reverse/dph/Main.hs b/dph-examples/imaginary/Reverse/dph/Main.hs
new file mode 100644
index 0000000..e1b3242
--- /dev/null
+++ b/dph-examples/imaginary/Reverse/dph/Main.hs
@@ -0,0 +1,56 @@
+
+import Util
+import Timing
+import Randomish
+import System.Environment
+import System.Random
+import Control.Exception
+import qualified ReverseVector                  as RV
+import qualified ReverseVectorised              as RD
+import qualified Data.Array.Parallel.PArray     as P
+import qualified Data.Vector.Unboxed            as V
+
+
+main 
+ = do   args    <- getArgs
+        
+        case args of
+         [alg, count]   
+           |  not $ isPowerOfTwo (read count)
+           -> error "reverse: length of array must be a power of two."
+
+           | otherwise -> run alg (read count)
+
+         _ -> usage
+
+
+run "vectorised" count
+ = do   let arr = P.fromList [0 .. count - 1]
+        arr `seq` return ()     
+                
+        (arrReversed, tElapsed)
+         <- time
+         $  let  arr'    = RD.treeReversePA arr
+            in   arr' `seq` return arr'
+                
+        putStr  $ prettyTime tElapsed
+
+run "vector" count
+ = do   let arr = V.fromList [0 .. count - 1]
+        arr `seq` return ()
+        
+        (arrReversed, tElapsed)
+         <- time
+         $  let arr'    = RV.treeReverse arr
+            in  arr' `seq` return arr'
+            
+        putStr  $ prettyTime tElapsed
+
+run _ _
+ = usage
+
+
+usage   = putStr $ unlines
+        [ "usage: reverse <algorithm> <count>\n"
+        , "  algorithm one of " ++ show ["vectorised"]
+        , ""]
diff --git a/dph-examples/imaginary/Reverse/dph/ReverseVector.hs b/dph-examples/imaginary/Reverse/dph/ReverseVector.hs
new file mode 100644
index 0000000..e0d275c
--- /dev/null
+++ b/dph-examples/imaginary/Reverse/dph/ReverseVector.hs
@@ -0,0 +1,21 @@
+
+module ReverseVector
+        (treeReverse)
+where
+import qualified Data.Vector.Unboxed as V
+import Data.Vector.Unboxed              (Vector)
+
+-- | Reverse the elements in an array using a tree.
+treeReverse :: Vector Int -> Vector Int
+{-# NOINLINE treeReverse #-}
+treeReverse xx
+        | V.length xx == 1
+        = xx
+        
+        | otherwise
+        = let   len     = V.length xx
+                half    = len `div` 2
+                s1      = V.slice 0    half  xx
+                s2      = V.slice half half  xx         
+          in    treeReverse s2 V.++ treeReverse s1
+
diff --git a/dph-examples/imaginary/Reverse/dph/ReverseVectorised.hs b/dph-examples/imaginary/Reverse/dph/ReverseVectorised.hs
new file mode 100644
index 0000000..a4ace75
--- /dev/null
+++ b/dph-examples/imaginary/Reverse/dph/ReverseVectorised.hs
@@ -0,0 +1,29 @@
+{-# LANGUAGE ParallelArrays #-}
+{-# OPTIONS -fvectorise #-}
+module ReverseVectorised        
+        (treeReversePA)
+where
+import Data.Array.Parallel.Prelude
+import Data.Array.Parallel.Prelude.Int
+import qualified Prelude as P
+
+
+treeReversePA :: PArray Int -> PArray Int
+{-# NOINLINE treeReversePA #-}
+treeReversePA ps
+        = toPArrayP (treeReverse (fromPArrayP ps))
+
+
+-- | Reverse the elements in an array using a tree.
+treeReverse :: [:Int:] -> [:Int:]
+{-# NOINLINE treeReverse #-}
+treeReverse xx
+        | lengthP xx == 1
+        = xx
+        
+        | otherwise
+        = let   len     = lengthP xx
+                half    = len `div` 2
+                s1      = sliceP 0    half xx
+                s2      = sliceP half len  xx           
+          in    treeReverse s2 +:+ treeReverse s1