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<DIV><FONT size=2>Hi,</FONT></DIV>
<DIV> </DIV>
<DIV style="TEXT-INDENT: 2em">I have a llvm-pass in hand written by other
people. There are following statements that I couldn't understand:</DIV>
<DIV style="TEXT-INDENT: 2em"> </DIV>
<DIV
style="TEXT-INDENT: 2em">-------------------------------program----------------------------------------------------</DIV>
<DIV style="TEXT-INDENT: 2em">
<DIV>...</DIV>
<DIV>if (isa<CallInst>(inst) || isa<InvokeInst>(inst)) {</DIV>
<DIV> const CallSite cs(inst);</DIV>
<DIV> if (cs.getCalledFunction() == NULL)</DIV>
<DIV> return dealAtIndirectCall(cs);</DIV>
<DIV> else</DIV>
<DIV> return dealAtDirectCall(cs);</DIV>
<DIV>}</DIV></DIV>
<DIV style="TEXT-INDENT: 2em">...</DIV>
<DIV
style="TEXT-INDENT: 2em">-------------------------------------------------------------------------------------------</DIV>
<DIV style="TEXT-INDENT: 2em"> </DIV>
<DIV style="TEXT-INDENT: 2em">My question is:</DIV>
<DIV style="TEXT-INDENT: 2em"> </DIV>
<DIV style="TEXT-INDENT: 2em">When does the called function equal NULL,
could you give an example? I mean what kind of call in source code could
change to this case in llvm-IR, could you give an example?</DIV>
<DIV style="TEXT-INDENT: 2em"> </DIV>
<DIV style="TEXT-INDENT: 2em">Thank you for your time.</DIV>
<DIV style="TEXT-INDENT: 2em"> </DIV>
<DIV style="TEXT-INDENT: 2em">Best Regards</DIV>
<DIV style="TEXT-INDENT: 2em"><FONT size=2></FONT> </DIV>
<DIV align=left><FONT size=2>2010-11-30 </FONT></DIV><FONT size=2>
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<DIV><FONT size=2><SPAN>WeiHu</SPAN></FONT></DIV></FONT></BODY></HTML>