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[AMD Official Use Only]<br>
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Hi,</div>
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<a href="https://reviews.llvm.org/D113366" id="LPlnk328483">https://reviews.llvm.org/D113366</a> and <a href="https://github.com/llvm/llvm-project/commit/1376301c87274bccf5565eb892173442782b1de3" id="LPNoLPOWALinkPreview">https://github.com/llvm/llvm-project/commit/1376301c87274bccf5565eb892173442782b1de3</a> <br>
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The above change causes a soft hang for the below IR in InstCombine Transform.</div>
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define i32 @p0(i32 %CF_init) {
<div> %t0 = add i32 %CF_init, -3</div>
<div> %t1 = icmp ugt i32 %t0, 1</div>
<div> %t2 = select i1 %t1, i32 -3, i32 1</div>
<div> ret i32 %t2</div>
<div>}</div>
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tryToReuseConstantFromSelectInComparison() from InstCombineSelect.cpp will replace select with inverse icmp and select. 1376301c8727 change when it sees a icmp ugt will replace with icmp ult. InstCombinerImpl::run() in InstructionCombining.cpp, will run these
transforms in a loop and it never ends. This is causing soft hang.<br>
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icmp ugt is always transformed to icmp ult. Issue is with this transform. Commenting out the change fixes the soft hang issue.</div>
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Any suggestion on other ways of fixing this in <span style="background-color:rgb(255, 255, 255);display:inline !important">InstructionCombining transform pass?</span></div>
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Regards,</div>
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Chaitanya</div>
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