+<div class="doc_text">
+
+<p>Similarly to debugging incorrect compilation by mis-behaving passes, you can
+debug incorrect code generation by either LLC or the JIT, using
+<tt>bugpoint</tt>. The process <tt>bugpoint</tt> follows in this case is to try
+to narrow the code down to a function that is miscompiled by one or the other
+method, but since for correctness, the entire program must be run,
+<tt>bugpoint</tt> will compile the code it deems to not be affected with the C
+Backend, and then link in the shared object it generates.</p>
+
+<p>To debug the JIT:</p>
+
+<div class="doc_code">
+<pre>
+bugpoint -run-jit -output=[correct output file] [bitcode file] \
+ --tool-args -- [arguments to pass to lli] \
+ --args -- [program arguments]
+</pre>
+</div>
+
+<p>Similarly, to debug the LLC, one would run:</p>
+
+<div class="doc_code">
+<pre>
+bugpoint -run-llc -output=[correct output file] [bitcode file] \
+ --tool-args -- [arguments to pass to llc] \
+ --args -- [program arguments]
+</pre>
+</div>
+
+<p><b>Special note:</b> if you are debugging MultiSource or SPEC tests that
+already exist in the <tt>llvm/test</tt> hierarchy, there is an easier way to
+debug the JIT, LLC, and CBE, using the pre-written Makefile targets, which
+will pass the program options specified in the Makefiles:</p>
+
+<div class="doc_code">
+<p><tt>
+cd llvm/test/../../program<br>
+make bugpoint-jit
+</tt></p>
+</div>
+
+<p>At the end of a successful <tt>bugpoint</tt> run, you will be presented
+with two bitcode files: a <em>safe</em> file which can be compiled with the C
+backend and the <em>test</em> file which either LLC or the JIT
+mis-codegenerates, and thus causes the error.</p>
+
+<p>To reproduce the error that <tt>bugpoint</tt> found, it is sufficient to do
+the following:</p>
+
+<ol>
+
+<li><p>Regenerate the shared object from the safe bitcode file:</p>
+
+<div class="doc_code">
+<p><tt>
+<b>llc</b> -march=c safe.bc -o safe.c<br>
+<b>gcc</b> -shared safe.c -o safe.so
+</tt></p>
+</div></li>
+
+<li><p>If debugging LLC, compile test bitcode native and link with the shared
+ object:</p>
+
+<div class="doc_code">
+<p><tt>
+<b>llc</b> test.bc -o test.s -f<br>
+<b>gcc</b> test.s safe.so -o test.llc<br>
+./test.llc [program options]
+</tt></p>
+</div></li>
+
+<li><p>If debugging the JIT, load the shared object and supply the test
+ bitcode:</p>
+
+<div class="doc_code">
+<p><tt><b>lli</b> -load=safe.so test.bc [program options]</tt></p>
+</div></li>
+
+</ol>
+
+</div>
+
+<!-- *********************************************************************** -->
+<hr>
+<address>
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+ <a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
+ <a href="http://llvm.org">The LLVM Compiler Infrastructure</a>
+ <br>
+ Last modified: $Date$
+</address>
+
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