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<p class="MsoNormal">Hi all,</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I¡¯m currently writing an IR pass that¡¯s required to match a ¡®br¡¯ instruction (in IR) with a specific AST if statement. Matching itself can be done quite easily through DebugLoc, but I realized that the ¡®way¡¯ (as in where the control flow
continues after it¡¯s been (not-)taken) of a branch can be changed in the course of IR optimizations. For example, a branch ¡®if (x == 0)¡¯ can be semantically transformed to ¡®if (x != 0)¡¯ in the resulting IR.</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My question is, <i>how can I know such way-changing transformation has been done on which branches?</i> Or, is there any way I can prevent such way-changes during optimization?</p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,</p>
<p class="MsoNormal">Gwangmu Lee.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<b><span style="font-size:11.0pt">Gwangmu Lee</span></b><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" align="left" style="text-align:left;text-autospace:ideograph-numeric ideograph-other;word-break:keep-all">
<span style="font-size:11.0pt">Ph.D. Student<o:p></o:p></span></p>
<p class="MsoNormal" align="left" style="text-align:left;text-autospace:ideograph-numeric ideograph-other;word-break:keep-all">
+82) 10 4114 7441<o:p></o:p></p>
<p class="MsoNormal" align="left" style="text-align:left;text-autospace:ideograph-numeric ideograph-other;word-break:keep-all">
Room 615, Bldg 301, Seoul National University, <br>
Gwanak-ro 1, Gwanak-gu, Seoul, South Korea.<o:p></o:p></p>
<p class="MsoNormal" align="left" style="text-align:left;text-autospace:ideograph-numeric ideograph-other;word-break:keep-all">
<a href="http://compsec.snu.ac.kr/~gwangmu">http://compsec.snu.ac.kr/~gwangmu</a><o:p></o:p></p>
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<span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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