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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Cameron wrote:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal">> The scalar constrained intrinsics would prevent vectorization, so you hopefully wouldn't see a vector
<o:p></o:p></p>
<p class="MsoNormal">> sqrt/etc instruction with scalar input(s). I don't think the X86 backend itself would select a vector
<o:p></o:p></p>
<p class="MsoNormal">> instruction for a scalar operation (I could be wrong).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I fear it would, because they’re faster. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">> If your user/frontend is issuing a vector instruction, the user/frontend would be responsible for
<o:p></o:p></p>
<p class="MsoNormal">> inserting safe values as needed (or masking on targets that support it).<o:p></o:p></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Our code is all C, with no assembler, so it has no way to issue vector instructions.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal">> Only a small number of people are currently working on this. New contributors are welcome...<span style="mso-fareast-language:EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">The learning curve before I could do anything useful makes it very hard to justify spending working
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">hours on this. I frankly lack the enthusiasm for spending lots of my own time on this.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt">-- <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt">John Dallman<o:p></o:p></span></p>
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<p style="font-family:Arial; font-size:70%">-----------------<br>
Siemens Industry Software Limited is a limited company registered in England and Wales.<br>
Registered number: 3476850.<br>
Registered office: Faraday House, Sir William Siemens Square, Frimley, Surrey, GU16 8QD.
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