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<p class="MsoNormal">Hi guys,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m running into the following assert in InstrEmiiter::EmitMachineNode() with the RET instruction:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">#ifndef NDEBUG<o:p></o:p></p>
<p class="MsoNormal"> Unsigned NumMIOperands = NodeOperands + NumResults;<o:p></o:p></p>
<p class="MsoNormal"> if (II.isVariadic())<o:p></o:p></p>
<p class="MsoNormal"> {<o:p></o:p></p>
<p class="MsoNormal"> assert(NumMIOperands >= II.getNumOperands() &&<o:p></o:p></p>
<p class="MsoNormal"> “Too few operands for a variadic node!”);<o:p></o:p></p>
<p class="MsoNormal"> }<o:p></o:p></p>
<p class="MsoNormal"> else<o:p></o:p></p>
<p class="MsoNormal"> {<o:p></o:p></p>
<p class="MsoNormal"> assert(NumMIOperands >= II.getNumOperands() &&
<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.4in">NumMIOperands <= II.getNumOperands() + II.getNumImplicitDefs() + NumImpUses &&<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:1.0in"> “#operands for dag node doesn’t match .td file!”);<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:.5in">}<o:p></o:p></p>
<p class="MsoNormal">#endif<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">And the reason seems to be that “NumImpUses” only takes into account the number of the physical registers?
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The pattern we have for RET is <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Let isTerminator =1, isReturn =1 in<o:p></o:p></p>
<p class="MsoNormal">{<o:p></o:p></p>
<p class="MsoNormal"> Multiclass __RET< SDNode node, Opcode op, string asmstr> {<o:p></o:p></p>
<p class="MsoNormal"> def : OP <op, 0, (outs), (ins), !strconcat(asmstr, “ “), [(node)]>;
<o:p></o:p></p>
<p class="MsoNormal"> }<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If I added “variable_ops” for the ins, it seems to then go to the “isvariadic” path without hitting the assert.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Let isTerminator =1, isReturn =1 in<o:p></o:p></p>
<p class="MsoNormal">{<o:p></o:p></p>
<p class="MsoNormal"> Multiclass __RET< SDNode node, Opcode op, string asmstr> {<o:p></o:p></p>
<p class="MsoNormal"> def : OP <op, 0, (outs), (ins <b>
<i>variable_ops</i></b>), !strconcat(asmstr, “ “), [(node)]>; <o:p></o:p></p>
<p class="MsoNormal"> }<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does this approach sound reasonable? I noticed that the “variable_ops” has been removed for CALL instructions for many backends. I was wondering if this is not going to be supported by RET either?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks a lot,<o:p></o:p></p>
<p class="MsoNormal">- Chad<o:p></o:p></p>
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