<div class="doc_text">
<p>The <tt><a href="http://llvm.org/doxygen/classllvm_1_1User.html">
-User</a></tt> class provides a base for expressing the ownership of <tt>User</tt>
+User</a></tt> class provides a basis for expressing the ownership of <tt>User</tt>
towards other <tt><a href="http://llvm.org/doxygen/classllvm_1_1Value.html">
Value</a></tt>s. The <tt><a href="http://llvm.org/doxygen/classllvm_1_1Use.html">
Use</a></tt> helper class is employed to do the bookkeeping and to facilitate <i>O(1)</i>
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<div class="doc_subsubsection">
- <a name="PATypeHolder">Interaction and relationship between <tt>User</tt> and <tt>Use</tt> objects</a>
+ <a name="Use2User">Interaction and relationship between <tt>User</tt> and <tt>Use</tt> objects</a>
</div>
<div class="doc_text">
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<div class="doc_subsubsection">
- <a name="PATypeHolder">The waymarking algorithm</a>
+ <a name="Waymarking">The waymarking algorithm</a>
</div>
<div class="doc_text">
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<div class="doc_subsubsection">
- <a name="PATypeHolder">Reference implementation</a>
+ <a name="ReferenceImpl">Reference implementation</a>
</div>
<div class="doc_text">
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<div class="doc_subsubsection">
- <a name="PATypeHolder">Tagging considerations</a>
+ <a name="Tagging">Tagging considerations</a>
</div>
<p>
For layout b) instead of the <tt>User</tt> we find a pointer (<tt>User*</tt> with LSBit set).
Following this pointer brings us to the <tt>User</tt>. A portable trick ensures
that the first bytes of <tt>User</tt> (if interpreted as a pointer) never has
-the LSBit set.</p>
+the LSBit set. (Portability is relying on the fact that all known compilers place the
+<tt>vptr</tt> in the first word of the instances.)</p>
</div>
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<div class="doc_subsubsection">
- <a name="m_Value">Important Public Methods</a>
+ <a name="m_Type">Important Public Methods</a>
</div>
<div class="doc_text">
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<div class="doc_subsubsection">
- <a name="m_Value">Important Derived Types</a>
+ <a name="derivedtypes">Important Derived Types</a>
</div>
<div class="doc_text">
<dl>