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<div class="elementToProof"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);" class="elementToProof">Sorry if this was previously discussed. I am new to the list.</span></div>
<div class="elementToProof"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);" class="elementToProof"><br>
</span></div>
<div class="elementToProof"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);" class="elementToProof ContentPasted1 ContentPasted2">With current API, it seems that if
one want to get the lanes with highest bit set, one can use Vector::compare(LT, 0). In the backend, this seems to be translated to something like vpcmpgtb followed by vpmovmskb. However, Gather the highest bit on x86 only need a movemask operation.
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<div class="elementToProof"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);" class="elementToProof ContentPasted1 ContentPasted2"><br>
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<ul>
<li style="font-size: 12pt; font-family: Calibri, Arial, Helvetica, sans-serif; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);" class="elementToProof ContentPasted1 ContentPasted2">I wonder if such operations can be optimized if the given constant
is special (such as 0)</span></li><li style="font-size: 12pt; font-family: Calibri, Arial, Helvetica, sans-serif; color: rgb(0, 0, 0);" class="elementToProof">
<span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);" class="elementToProof ContentPasted1 ContentPasted2">Or if we can finally have a
<code>gatherBits()</code> operation. I know that movemask operations are not available on platforms like aarch64, but libraries like SIMDE has given some examples on how to emulate these operations on other platforms.</span></li></ul>
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<span style="font-family: "Calibri Light", "Helvetica Light", sans-serif;">Schrodinger ZHU Yifan, Ph.D. Student</span></div>
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<div class="ContentPasted0"><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif;">Computer Science Department, University of Rochester</span></div>
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<div class="ContentPasted0"><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif; font-size: 10pt;"><b>Personal Email:</b></span><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif; font-size: 10pt;"> i@zhuyi.fan</span></div>
<div class="ContentPasted0"><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif; font-size: 10pt;"><b>Work Email:</b></span><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif; font-size: 10pt;"> yifanzhu@rochester.edu</span></div>
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<div class="ContentPasted0"><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif; font-size: 10pt;"><b>Github:</b></span><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif; font-size: 10pt;"> SchrodingerZhu</span></div>
<div class="ContentPasted0"><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif; font-size: 10pt;"><b>GPG Fingerprint:</b></span><span style="font-family: "Calibri Light", "Helvetica Light", sans-serif; font-size: 10pt;"> BA02CBEB8CB5D8181E9368304D2CC545A78DBCC3</span></div>
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