Update of /cvsroot/mockpp/mockpp/mockpp/docs/en
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv1247/mockpp/docs/en
Modified Files:
dev_embedded.docbook
Log Message:
extend
Index: dev_embedded.docbook
===================================================================
RCS file: /cvsroot/mockpp/mockpp/mockpp/docs/en/dev_embedded.docbook,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -d -r1.2 -r1.3
--- dev_embedded.docbook 2 Dec 2005 17:28:36 -0000 1.2
+++ dev_embedded.docbook 3 Dec 2005 15:56:33 -0000 1.3
@@ -1,45 +1,88 @@
<sect1 id="embedded-systems">
-<title>Embedded Systems</title>
-
+<title>Working With Embedded Systems</title>
-<para>text
+<para>There are hidden costs concerning memory resources when programming in
+C++. On a desktop system with plenty of virtual memory you don't neccessarily
+recognize it. But working with embedded systems is different as there is only a
+limited amout of physical ram available.</para>
-<programlisting>
+<para>For that reasons it is important to know the places where he compiler adds
+additional code:
-Full featured: 322400
+<variablelist>
-built-in stl: 230628
+ <varlistentry>
+ <term>Standard Template Library (STL)</term>
+ <listitem>Templates and other inline code may increase the resulting footprint
+ of the binary.</listitem>
+ </varlistentry>
-built-in stl, no rtti: 218204
+ <varlistentry>
+ <term>Exceptions</term>
+ <listitem>After throwing an exception the complier must cleanup and
+ destroy all automatic objects in the previous scopes. This bookkeeping
+ consumes space as well.</listitem>
+ </varlistentry>
-built-in stl, no exceptions: 193588
+ <varlistentry>
+ <term>Runtime Type Information (RTTI)</term>
+ <listitem>To provide information about an object at runtime the
+ compiler includes data like the class name or the inheritance tree
+ in the binary. </listitem>
+ </varlistentry>
-built-in stl, no rtti, no exceptions: 180588
+</variablelist>
-------------
+</para>
-Cost per feature
+<para>The following table shows the the size of the &mockpp; library when
+compiled with different settings. The size ranged from around 320KiB with the
+default settings down to 180KiB with as many features disabled as possible.
-stl: 91772 == 28%
+<table><title>Proportion of Important Features</title>
+<tgroup cols='3' align='left' colsep='1' rowsep='1'>
+<thead>
+ <row>
+ <entry>Feature</entry><entry>Number of Bytes</entry><entry>Percentage</entry>
+ </row>
+</thead>
-rtti: 12424 == 4%
+<tbody>
+ <row>
+ <entry>regular STL</entry><entry>92KiB</entry><entry>28%</entry>
+ </row>
-exceptions: 37040 == 11%
+ <row>
+ <entry>RTTI</entry><entry>12KiB</entry><entry>4%</entry>
+ </row>
-production code: 188588 = 58%
+ <row>
+ <entry>Exceptions</entry><entry>37KiB</entry><entry>11%</entry>
+ </row>
-</programlisting>
+ <row>
+ <entry>Library Code</entry><entry>180KiB</entry><entry>57%</entry>
+ </row>
+</tbody>
+</tgroup>
+</table>
</para>
-<para>There are a few things that are not obvious but might become interesting:
+<para>
-<itemizedlist>
+<programlisting>
+
+void forwardMalfunctionData(const T &e)
+
+#define MOCKPP_THROW(x) throw (x)
+#define MOCKPP_RETHROW throw
+#define MOCKPP_TRY try
+#define MOCKPP_CATCH(x) (x)
+#define MOCKPP_CATCH_ALL catch(...)
+
+</programlisting>
- <listitem>In the same manner <literal>MOCKPP_STRING</literal> yields either a
- <token>std::string</token> or a <token>std::wstring</token>.
- </listitem>
-</itemizedlist>
</para>
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