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<p class="MsoNormal" style="mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in">
<br>
I think this seems about right. We shouldn't re-compare the trip counts in the epilogue loop if the alias check is false anyway:<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"><tt><span style="font-size:10.0pt;background:white">int start = 0;</span></tt><b><span style="font-family:"Courier New""><br>
</span></b><tt><span style="font-size:10.0pt;background:white">if (n >= vf) {</span></tt><span style="font-size:10.0pt;font-family:"Courier New";background:white"><br>
<tt> if (check) {</tt><br>
<tt> for (...; start += vf)</tt><br>
<tt> ...</tt><br>
<tt> } else { goto scalar; }</tt><br>
<tt>} else { goto scalar; }</tt><br>
</span><br>
<tt><span style="font-size:10.0pt;background:white">if (n - start >= vf2) {</span></tt><span style="font-size:10.0pt;font-family:"Courier New";background:white"><br>
<tt> for (...; start += vf2)</tt><br>
<tt> ...</tt><br>
<tt>}</tt><br>
</span><br>
<tt><span style="font-size:10.0pt">scalar:</span></tt><br>
<tt><span style="font-size:10.0pt;background:white">for (i = start; i < n; ++i) {</span></tt><span style="font-size:10.0pt;font-family:"Courier New";background:white"><br>
<tt> …</tt><br>
<tt>}</tt></span><o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in"><br>
-Hal<br>
<br>
<br>
<o:p></o:p></p>
<pre><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D">This layout looks OK *<b>only when alias check is required*</b>, but what if alias check is not required in that case the layout probably will looks like this:<o:p></o:p></span></pre>
<pre><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></pre>
<p class="MsoNormal" style="margin-left:.5in"><tt><span style="font-size:10.0pt;background:white">int start = 0;</span></tt><b><span style="font-family:"Courier New""><br>
</span></b><tt><span style="font-size:10.0pt;background:white">if (n >= vf) {</span></tt><span style="font-size:10.0pt;font-family:"Courier New";background:white"><br>
<tt><s> if (check) {</s></tt><br>
<tt> for (...; start += vf)</tt><br>
<tt> ...</tt><br>
<tt><s> } else { goto scalar; }</s></tt><br>
<tt>} else { goto scalar; }</tt><br>
</span><br>
<tt><span style="font-size:10.0pt;background:white">if (n - start >= vf2) {</span></tt><span style="font-size:10.0pt;font-family:"Courier New";background:white"><br>
<tt> for (...; start += vf2)</tt><br>
<tt> ...</tt><br>
<tt>}</tt><br>
</span><br>
<tt><span style="font-size:10.0pt">scalar:</span></tt><br>
<tt><span style="font-size:10.0pt;background:white">for (i = start; i < n; ++i) {</span></tt><span style="font-size:10.0pt;font-family:"Courier New";background:white"><br>
<tt> …</tt><br>
<tt>}</tt></span><o:p></o:p></p>
<pre><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></pre>
<pre><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D">For ‘n < vf’ it should try executing epilog vector loop but in this layout it will execute scalar loop.<o:p></o:p></span></pre>
<pre><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D"><o:p> </o:p></span></pre>
<pre><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D">Regards,<o:p></o:p></span></pre>
<pre><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D">Ashutosh<o:p></o:p></span></pre>
<pre><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D"><o:p> </o:p></span></pre>
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