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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">from the SD / SelectionDAG form of a global-virt-reg, IE a CopyToReg or CopyFromReg<o:p></o:p></p>
<p class="MsoNormal">where the Reg is a virtual-register (not a physical-register),<o:p></o:p></p>
<p class="MsoNormal">I need to compute the set of all other global-virt-regs that this one is connected<o:p></o:p></p>
<p class="MsoNormal">to through PHI nodes<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">as the PHI nodes set up equivalence relations,<o:p></o:p></p>
<p class="MsoNormal">I should be able to use ADT/EquivalenceClasses.h<o:p></o:p></p>
<p class="MsoNormal">which seems to implement a generic Union-Find algorithm,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I also note that there do not seem to be any uses of EquivalenceClasses<o:p></o:p></p>
<p class="MsoNormal">in CodeGen, so perhaps no one has had to do this before and I will<o:p></o:p></p>
<p class="MsoNormal">have to start from scratch ?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">thanks,<o:p></o:p></p>
<p class="MsoNormal">--Peter Lawrence.<o:p></o:p></p>
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