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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The PHI elimination pass calls the function copyRegToReg for
copy placement and then later tries to setkill to the temporary virtual
register used in copy placement. For this setkill action it looks only in one
instruction (last instruction for copyRegToReg) for virtual register with no
use.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>My target has only one register and I can’t do
copyRegToReg in one instruction only. So I create two instructions (one:SrcReg
to Stack , two:Stack to DestReg). The SrcReg here is the temporary virtual
register (for PHI elimination) which should be setkill. However, the PHI
Elimination pass looks only in last instruction (here: Stack to DestReg) for
any NoUse register and does not find any. Therefore the intended setkill does
not take place. This causes an assertion failure saying <b><span
style='font-weight:bold'>“PHI elimination vreg should have one kill, the
PHI itself”.<o:p></o:p></span></b></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Please provide some input on how this can be solved.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Regards<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Sachin <o:p></o:p></span></font></p>
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