<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">Hi All,</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default"><span style="font-family:arial,helvetica,sans-serif">  While compiling libgcc, I find I have to deal with UMULO (overflow-aware unsigned multiplication) SDNode. UMULO returns the result of multiplication, and a boolean indicating overflow occurred or not. Our target's multiply instruction doesn't care (detect) overflow. I am wondering if I can always set the boolean to false. I am not sure about this as I see AArch64 [1] seems trying to emulate the overflow behavior.</span></div><div class="gmail_default"><span style="font-family:arial,helvetica,sans-serif"><br></span></div><div class="gmail_default"><span style="font-family:arial,helvetica,sans-serif">  Thanks.</span></div><div class="gmail_default"><span style="font-family:arial,helvetica,sans-serif"><br></span></div><div class="gmail_default"><span style="font-family:arial,helvetica,sans-serif">[1] </span><font face="arial, helvetica, sans-serif"><a href="https://github.com/llvm-mirror/llvm/blob/master/lib/Target/AArch64/AArch64ISelLowering.cpp">https://github.com/llvm-mirror/llvm/blob/master/lib/Target/AArch64/AArch64ISelLowering.cpp</a></font></div><div><br></div><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">​Regards,</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">chenwj​</div><br></div>-- <br><div class="gmail_signature"><div dir="ltr"><div>Wei-Ren Chen (陳韋任)<br>Homepage: <a href="https://people.cs.nctu.edu.tw/~chenwj" target="_blank">https://people.cs.nctu.edu.tw/~chenwj</a></div></div></div>
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