[project @ 2005-07-28 15:41:47 by simonmar]

[ghc-hetmet.git] / ghc / docs / users_guide / using.xml

diff --git a/ghc/docs/users_guide/using.xml b/ghc/docs/users_guide/using.xml
index 80b8790..25869d9 100644 (file)
--- a/ghc/docs/users_guide/using.xml
+++ b/ghc/docs/users_guide/using.xml
@@ -1290,6 +1290,18 @@ f "2"    = 2
 
        <varlistentry>
          <term>
+            <option>-fno-cse</option>
+            <indexterm><primary><option>-fno-cse</option></primary></indexterm>
+          </term>
+         <listitem>
+           <para>Turns off the common-sub-expression elimination optimisation.
+             Can be useful if you have some <literal>unsafePerformIO</literal>
+           expressions that you don't want commoned-up.</para>
+         </listitem>
+       </varlistentry>
+
+       <varlistentry>
+         <term>
             <option>-fno-strictness</option>
             <indexterm><primary><option>-fno-strictness</option></primary></indexterm>
           </term>
@@ -1301,12 +1313,27 @@ f "2"    = 2
 
        <varlistentry>
          <term>
-            <option>-fno-cpr-analyse</option>
-            <indexterm><primary><option>-fno-cpr-analyse</option></primary></indexterm>
+            <option>-fno-full-laziness</option>
+            <indexterm><primary><option>-fno-full-laziness</option></primary></indexterm>
+          </term>
+         <listitem>
+           <para>Turns off the full laziness optimisation (also known as
+             let-floating).  Full laziness increases sharing, which can lead
+             to increased memory residency.</para>
+         </listitem>
+       </varlistentry>
+
+       <varlistentry>
+         <term>
+            <option>-fno-state-hack</option>
+            <indexterm><primary><option>-fno-state-hack</option></primary></indexterm>
           </term>
          <listitem>
-           <para>Turns off the CPR (constructed product result)
-           analysis; it is somewhat experimental.</para>
+           <para>Turn off the "state hack" whereby any lambda with a
+             <literal>State#</literal> token as argument is considered to be
+             single-entry, hence it is considered OK to inline things inside
+             it.  This can improve performance of IO and ST monad code, but it
+           runs the risk of reducing sharing.</para> 
          </listitem>
        </varlistentry>