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<div class="moz-cite-prefix">On 6/12/14, 9:29 PM, Padefic wrote:<br>
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<div>I am doing a research project. I want to run the DSA pass
of LLVM, and use its result in Clang for automatic fixing. I
have to use Clang because the line numbers in Clang are
accurate so that I can change code accordingly, while LLVM IR
seems to lose the information. <br>
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<br>
If I understand what you're saying, you're building a refactoring
tool that does some analysis on the program and then changes the
original program's source code. Is this correct?<br>
<br>
I do not think that this is a good idea. DSA operates on the LLVM
IR. Not only will you have the headache of making DSA's results
available to Clang, but Clang "sees" the program at the Clang AST
level while DSA "sees" the program at the LLVM IR level. Mapping
DSA's results from the LLVM IR back to the AST that Clang creates
will be painful in the best case and will probably not work reliably
at all in the worst case.<br>
<br>
I think your best option is to build a points-to analysis that works
at the Clang AST level and put it into clang directly. There might
be the issue of how to build an inter-procedural points-to analysis
with Clang, but I think there either is a way for Clang to do that,
or there is work to make Clang do that.<br>
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<div>I need to access the objects created <span
style="line-height: 1.7;">in LLVM pass </span><span
style="line-height: 1.7;"> to get information. </span><span
style="line-height: 1.7;">Thank Bruce for your advice, could
you explain more about how to output using the C backend?
Does it mean to output to files, which then input into
Clang? I would appreciate any reference on this problem.</span></div>
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The C Backend generates C code instead of native assembly code. The
C code it generates is ugly and looks almost nothing like the
original C source code that was compiled. Again, if you're building
a refactoring tool, this is probably not what you want.<br>
<br>
Regards,<br>
<br>
John Criswell<br>
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