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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'>For the case, please see the “.ll” file
attached. Here I am doing a right shift on 32 bits by constant amount
(specifically by 8). <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 is an 8-bit target. Therefore while performing a
shift (right or left) on long (32 bits) it is legalized in 4 smaller units. After
performing the shift, this value should be stored at the same location. So
order of the stores does matter. But all 4 stores are parallel in the code and do
not have any control flow dependency between them. Therefore these stores are
scheduled in some order not correct for the result. <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'>Please provide some input on this. Also how does the
scheduler determine the order when 16-bit quantity is shifted (in the same
example) because the DAG for 16 bit shift is similar with both the stores in parallel.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I have tried shift operation for 64 bits on some 32 bit
targets also. The DAG looks similar with stores in parallel. How does the
scheduler determine the order in such cases?<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'>This is not a target specific doubt. But pic16 is the only
target that creates that such a scenario. For 8-bit target command line used:- <o:p></o:p></span></font></p>
<p class=MsoNormal><b><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial;font-weight:bold'><o:p> </o:p></span></font></b></p>
<p class=MsoNormal><b><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial;font-weight:bold'>llc –march=pic16 try.bc</span></font></b><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'><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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