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Make use of the doc_author and doc_code styles. <tt>'ify llvm names. Minor

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llvm-svn: 13760
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Chris Lattner 2004-05-25 17:44:58 +00:00
parent 0e78929263
commit aecfdd6324
1 changed files with 14 additions and 12 deletions
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26
docs/BytecodeFormat.html
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@ -38,10 +38,9 @@
</ol>
</li>
</ol>
<div class="doc_text">
<p><b>Written by <a href="mailto:rspencer@x10sys.com">Reid Spencer</a>
and <a href="mailto:sabre@nondot.org">Chris Lattner</a></b></p>
<p> </p>
<div class="doc_author">
<p>Written by <a href="mailto:rspencer@x10sys.com">Reid Spencer</a>
</p>
</div>
<!-- *********************************************************************** -->
<div class="doc_section"> <a name="abstract">Abstract </a></div>
@ -128,13 +127,16 @@ Values. Since the bytecode file is a <em>direct</em> representation of LLVM's
intermediate representation, there is a need to represent pointers in the file.
Slots are used for this purpose. For example, if one has the following assembly:
</p>
<pre><code>
%MyType = type { int, sbyte };
%MyVar = external global %MyType ;
</code></pre>
<p>there are two definitions. The definition of %MyVar uses %MyType and %MyType
is used by %MyVar. In the C++ IR this linkage between %MyVar and %MyType is
made explicitly by the use of C++ pointers. In bytecode, however, there's no
<div class="doc_code">
%MyType = type { int, sbyte }<br>
%MyVar = external global %MyType
</div>
<p>there are two definitions. The definition of <tt>%MyVar</tt> uses
<tt>%MyType</tt>. In the C++ IR this linkage between <tt>%MyVar</tt> and
<tt>%MyType</tt> is
explicit through the use of C++ pointers. In bytecode, however, there's no
ability to store memory addresses. Instead, we compute and write out slot
numbers for every type and Value written to the file.</p>
<p>A slot number is simply an unsigned 32-bit integer encoded in the variable
@ -146,7 +148,7 @@ written to the bytecode file in a list (sequentially). Their order in that list
determines their slot number. This means that slot #1 doesn't mean anything
unless you also specify for which type you want slot #1. Types are handled
specially and are always written to the file first (in the Global Type Pool) and
in such a way that both forward and backward references of the types can be
in such a way that both forward and backward references of the types can often be
resolved with a single pass through the type pool. </p>
<p>Slot numbers are also kept small by rearranging their order. Because of the
structure of LLVM, certain values are much more likely to be used frequently