X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=docs%2Fusers_guide%2Fparallel.xml;h=76d38dc6464031ed61928a6df316d172f81d5361;hb=d5ab3b5e415ebdff8906dcac3451e7448d6bdb11;hp=7792ea651abde3e7ee45d4dc7606d90e581bf66f;hpb=fcf6ab7b3dfe389e971059bbf21dfa8179b20f5e;p=ghc-hetmet.git

diff --git a/docs/users_guide/parallel.xml b/docs/users_guide/parallel.xml
index 7792ea6..76d38dc 100644
--- a/docs/users_guide/parallel.xml
+++ b/docs/users_guide/parallel.xml
@@ -5,7 +5,7 @@
   </indexterm>
 
   <para>GHC implements some major extensions to Haskell to support 
-  concurrent and parallel programming.  Let us first etablish terminology:
+  concurrent and parallel programming.  Let us first establish terminology:
   <itemizedlist>
 	<listitem><para><emphasis>Parallelism</emphasis> means running
 	  a Haskell program on multiple processors, with the goal of improving
@@ -33,7 +33,7 @@
 	      url="http://research.microsoft.com/copyright/accept.asp?path=/users/simonpj/papers/concurrent-haskell.ps.gz">
 	      Concurrent Haskell paper</ulink> is still an excellent
 	      resource, as is <ulink
-	      url="http://research.microsoft.com/%7Esimonpj/papers/marktoberdorf">Tackling
+	      url="http://research.microsoft.com/%7Esimonpj/papers/marktoberdorf/">Tackling
 	      the awkward squad</ulink>.
   </para><para>
   To the programmer, Concurrent Haskell introduces no new language constructs;
@@ -83,7 +83,7 @@ All these features are described in the papers mentioned earlier.
   By default GHC runs your program on one processor; if you
      want it to run in parallel you must link your program
       with the <option>-threaded</option>, and run it with the RTS
-      <option>-N</option> option; see  <xref linkend="sec-using-smp" />).
+      <option>-N</option> option; see  <xref linkend="using-smp" />).
       The runtime will
       schedule the running Haskell threads among the available OS
       threads, running as many in parallel as you specified with the
@@ -110,7 +110,7 @@ All these features are described in the papers mentioned earlier.
     linkend="concurrent-haskell"/>), but the simplest mechanism for extracting parallelism from pure code is
       to use the <literal>par</literal> combinator, which is closely related to (and often used
       with) <literal>seq</literal>.  Both of these are available from <ulink
-	url="../libraries/base/Control-Parallel.html"><literal>Control.Parallel</literal></ulink>:</para>
+	url="../libraries/parallel/Control-Parallel.html"><literal>Control.Parallel</literal></ulink>:</para>
 
 <programlisting>
 infixr 0 `par`
@@ -136,7 +136,7 @@ import Control.Parallel
 
 nfib :: Int -&#62; Int
 nfib n | n &#60;= 1 = 1
-       | otherwise = par n1 (seq n2 (n1 + n2))
+       | otherwise = par n1 (seq n2 (n1 + n2 + 1))
                      where n1 = nfib (n-1)
                            n2 = nfib (n-2)</programlisting>
 
@@ -149,8 +149,8 @@ nfib n | n &#60;= 1 = 1
       (leaving the parent to evaluate the other branch).  Also, we must use
       <function>seq</function> to ensure that the parent will evaluate
       <varname>n2</varname> <emphasis>before</emphasis> <varname>n1</varname>
-      in the expression <literal>(n1 + n2)</literal>.  It is not sufficient
-      to reorder the expression as <literal>(n2 + n1)</literal>, because
+      in the expression <literal>(n1 + n2 + 1)</literal>.  It is not sufficient
+      to reorder the expression as <literal>(n2 + n1 + 1)</literal>, because
       the compiler may not generate code to evaluate the addends from left to
       right.</para>
 
@@ -163,12 +163,20 @@ nfib n | n &#60;= 1 = 1
 
     <para>More sophisticated combinators for expressing parallelism are
       available from the <ulink
-	url="../libraries/base/Control-Parallel-Strategies.html"><literal>Control.Parallel.Strategies</literal></ulink> module.
+	url="../libraries/parallel/Control-Parallel-Strategies.html"><literal>Control.Parallel.Strategies</literal></ulink> module.
       This module builds functionality around <literal>par</literal>,
       expressing more elaborate patterns of parallel computation, such as
       parallel <literal>map</literal>.</para>
   </sect2>
 
+<sect2><title>Data Parallel Haskell</title>
+  <para>GHC includes experimental support for Data Parallel Haskell (DPH). This code
+        is highly unstable and is only provided as a technology preview. More
+        information can be found on the corresponding <ulink
+        url="http://www.haskell.org/haskellwiki/GHC/Data_Parallel_Haskell">DPH
+        wiki page</ulink>.</para>
+</sect2>
+
 </sect1>
 
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