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<p class="MsoNormal"><span style="font-family:"Courier New"">When I have a MOV instruction in my dot-td-file with an explicit pattern<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> Def MOV Format_RR < ,,,,,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> [(set i32:$dst, i32:$src)]>;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">then Instruction Selection goes haywire, why is that ?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">(I have noticed that other targets get around this by defining their MOV<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">Instrs with an empty pattern, but that seems weird to me (and it’s<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">undocumented which also seems weird to me))<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">Unfortunately this is not an idle question, because my target has<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">separate Address and Data registers I need to add these NOP-ish defs:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> Def MOVDA Format_RR < ,,,,,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> [(set i32:$dst, (bitconvert p32:$src))]>;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> Def MOVAD Format_RR < ,,,,,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> [(set p32:$dst, (bitconvert i32:$src))]>;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">which actually work just fine, but when I also add these<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">even more NOP-ish defs:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> Def MOVDD Format_RR < ,,,,,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> [(set i32:$dst, (bitconvert i32:$src))]>;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> Def MOVAA Format_RR < ,,,,,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""> [(set p32:$dst, (bitconvert p32:$src))]>;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">then I start seeing I-Select going haywire again, why is that ?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">By “haywire” I mean –debug-only=isel shows really long lists<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">of “Match failed at index ###” ending in compilation failure,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">which are otherwise really short and don’t fail.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">--Peter Lawrence. <o:p>
</o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
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