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remove 'another common example', which doesn't work with VC++, and indent 

another example properly

llvm-svn: 21442
This commit is contained in:
Chris Lattner 2005-04-22 04:49:59 +00:00
parent 88e7b7288a
commit 16431f7b3c
1 changed files with 4 additions and 12 deletions
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16
llvm/docs/ProgrammersManual.html
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@ -292,8 +292,9 @@ file (note that you very rarely have to include this file directly).</p>
if (isa&lt;<a href="#Constant">Constant</a>&gt;(V) || isa&lt;<a href="#Argument">Argument</a>&gt;(V) || isa&lt;<a href="#GlobalValue">GlobalValue</a>&gt;(V))
return true;
<i>// Otherwise, it must be an instruction...</i>
return !L-&gt;contains(cast&lt;<a href="#Instruction">Instruction</a>&gt;(V)-&gt;getParent());
<i>// Otherwise, it must be an instruction...</i>
return !L-&gt;contains(cast&lt;<a href="#Instruction">Instruction</a>&gt;(V)-&gt;getParent());
}
</pre>
<p>Note that you should <b>not</b> use an <tt>isa&lt;&gt;</tt> test followed
@ -322,21 +323,12 @@ file (note that you very rarely have to include this file directly).</p>
call to <tt>isa&lt;&gt;</tt> and a call to <tt>cast&lt;&gt;</tt> into one
statement, which is very convenient.</p>
<p> Another common example is:</p>
<pre>
<i>// Loop over all of the phi nodes in a basic block</i>
BasicBlock::iterator BBI = BB-&gt;begin();
for (; <a href="#PhiNode">PHINode</a> *PN = dyn_cast&lt;<a href="#PHINode">PHINode</a>&gt;(BBI); ++BBI)
std::cerr &lt;&lt; *PN;
</pre>
<p>Note that the <tt>dyn_cast&lt;&gt;</tt> operator, like C++'s
<tt>dynamic_cast</tt> or Java's <tt>instanceof</tt> operator, can be abused.
In particular you should not use big chained <tt>if/then/else</tt> blocks to
check for lots of different variants of classes. If you find yourself
wanting to do this, it is much cleaner and more efficient to use the
InstVisitor class to dispatch over the instruction type directly.</p>
<tt>InstVisitor</tt> class to dispatch over the instruction type directly.</p>
</dd>