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<instructionsection id="cntp_r_pn" title="CNTP (predicate as counter)" type="instruction">
  <docvars>
    <docvar key="instr-class" value="sve2" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="CNTP" />
  </docvars>
  <heading>CNTP (predicate as counter)</heading>
  <desc>
    <brief>Set scalar to count from predicate-as-counter</brief>
    <description>
      <para>Counts the number of true elements in the source predicate and places the scalar result in the destination general-purpose register.</para>
    </description>
    <status>Green</status>
    <predicated>False</predicated>
    <uses_dit condition="FEAT_SVE2 is implemented or FEAT_SME is implemented">True</uses_dit>
  </desc>
  <alias_list howmany="0"></alias_list>
  <classes>
    <iclass name="SVE2" oneof="1" id="iclass_sve2" no_encodings="1" isa="A64">
      <docvars>
        <docvar key="instr-class" value="sve2" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="CNTP" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <arch_variants>
        <arch_variant name="FEAT_SVE2p1" feature="FEAT_SVE2p1" />
      </arch_variants>
      <regdiagram form="32" psname="CNTP-R.PN-_">
        <box hibit="31" width="8" settings="8">
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
        </box>
        <box hibit="23" width="2" name="size" usename="1">
          <c colspan="2"></c>
        </box>
        <box hibit="21" width="3" settings="3">
          <c>1</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="18" width="2" name="opc&lt;2:1&gt;" settings="2">
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="16" name="opc&lt;0&gt;" settings="1">
          <c>0</c>
        </box>
        <box hibit="15" width="5" settings="5">
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="10" name="vl" usename="1">
          <c></c>
        </box>
        <box hibit="9" settings="1">
          <c>1</c>
        </box>
        <box hibit="8" width="4" name="PNn" usename="1">
          <c colspan="4"></c>
        </box>
        <box hibit="4" width="5" name="Rd" usename="1">
          <c colspan="5"></c>
        </box>
      </regdiagram>
      <encoding name="cntp_r_pn_" oneofinclass="1" oneof="1" label="">
        <docvars>
          <docvar key="instr-class" value="sve2" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="CNTP" />
        </docvars>
        <asmtemplate><text>CNTP    </text><a link="sa_xd" hover="64-bit destination general-purpose register (field &quot;Rd&quot;)">&lt;Xd&gt;</a><text>, </text><a link="sa_pnn" hover="First source scalable predicate register (field &quot;PNn&quot;)">&lt;PNn&gt;</a><text>.</text><a link="sa_t" hover="Size specifier (field &quot;size&quot;) [B,D,H,S]">&lt;T&gt;</a><text>, </text><a link="sa_vl" hover="Vl specifier (field &quot;vl&quot;) [VLx2,VLx4]">&lt;vl&gt;</a></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="CNTP-R.PN-_" mylink="CNTP-R.PN-_" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">if !<a link="impl-aarch64.HaveSME2.0" file="shared_pseudocode.xml" hover="function: boolean HaveSME2()">HaveSME2</a>() &amp;&amp; !<a link="impl-aarch64.HaveSVE2p1.0" file="shared_pseudocode.xml" hover="function: boolean HaveSVE2p1()">HaveSVE2p1</a>() then UNDEFINED;
constant integer esize = 8 &lt;&lt; <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(size);
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(PNn);
integer d = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rd);
constant integer width = 2 &lt;&lt; <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(vl);</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="cntp_r_pn_" symboldefcount="1">
      <symbol link="sa_xd">&lt;Xd&gt;</symbol>
      <account encodedin="Rd">
        <intro>
          <para>Is the 64-bit name of the destination general-purpose register, encoded in the "Rd" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="cntp_r_pn_" symboldefcount="1">
      <symbol link="sa_pnn">&lt;PNn&gt;</symbol>
      <account encodedin="PNn">
        <intro>
          <para>Is the name of the first source scalable predicate register, with predicate-as-counter encoding, encoded in the "PNn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="cntp_r_pn_" symboldefcount="1">
      <symbol link="sa_t">&lt;T&gt;</symbol>
      <definition encodedin="size">
        <intro>Is the size specifier, </intro>
        <table class="valuetable">
          <tgroup cols="2">
            <thead>
              <row>
                <entry class="bitfield">size</entry>
                <entry class="symbol">&lt;T&gt;</entry>
              </row>
            </thead>
            <tbody>
              <row>
                <entry class="bitfield">00</entry>
                <entry class="symbol">B</entry>
              </row>
              <row>
                <entry class="bitfield">01</entry>
                <entry class="symbol">H</entry>
              </row>
              <row>
                <entry class="bitfield">10</entry>
                <entry class="symbol">S</entry>
              </row>
              <row>
                <entry class="bitfield">11</entry>
                <entry class="symbol">D</entry>
              </row>
            </tbody>
          </tgroup>
        </table>
      </definition>
    </explanation>
    <explanation enclist="cntp_r_pn_" symboldefcount="1">
      <symbol link="sa_vl">&lt;vl&gt;</symbol>
      <definition encodedin="vl">
        <intro>Is the vl specifier, </intro>
        <table class="valuetable">
          <tgroup cols="2">
            <thead>
              <row>
                <entry class="bitfield">vl</entry>
                <entry class="symbol">&lt;vl&gt;</entry>
              </row>
            </thead>
            <tbody>
              <row>
                <entry class="bitfield">0</entry>
                <entry class="symbol">VLx2</entry>
              </row>
              <row>
                <entry class="bitfield">1</entry>
                <entry class="symbol">VLx4</entry>
              </row>
            </tbody>
          </tgroup>
        </table>
      </definition>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="CNTP-R.PN-_" mylink="execute" enclabels="" sections="1" secttype="Operation">
      <pstext mayhavelinks="1" section="Execute" rep_section="execute">if <a link="impl-aarch64.HaveSVE2p1.0" file="shared_pseudocode.xml" hover="function: boolean HaveSVE2p1()">HaveSVE2p1</a>() then <a link="impl-aarch64.CheckSVEEnabled.0" file="shared_pseudocode.xml" hover="function: CheckSVEEnabled()">CheckSVEEnabled</a>(); else <a link="impl-aarch64.CheckStreamingSVEEnabled.0" file="shared_pseudocode.xml" hover="function: CheckStreamingSVEEnabled()">CheckStreamingSVEEnabled</a>();
constant integer VL = <a link="impl-aarch64.CurrentVL.read.none" file="shared_pseudocode.xml" hover="accessor: integer CurrentVL">CurrentVL</a>;
constant integer PL = VL DIV 8;
constant integer elements = VL DIV esize;
bits(PL) pred = <a link="impl-aarch64.P.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) P[integer n, integer width]">P</a>[n, PL];
bits(PL*4) mask = <a link="impl-aarch64.CounterToPredicate.2" file="shared_pseudocode.xml" hover="function: bits(width) CounterToPredicate(bits(16) pred, integer width)">CounterToPredicate</a>(pred&lt;15:0&gt;, PL*4);
bits(64) sum = <a link="impl-shared.Zeros.1" file="shared_pseudocode.xml" hover="function: bits(N) Zeros(integer N)">Zeros</a>(64);
constant integer limit = elements * width;

for e = 0 to limit-1
    if <a link="impl-aarch64.ActivePredicateElement.3" file="shared_pseudocode.xml" hover="function: boolean ActivePredicateElement(bits(N) pred, integer e, integer esize)">ActivePredicateElement</a>(mask, e, esize) then
        sum = sum + 1;
<a link="impl-aarch64.X.write.2" file="shared_pseudocode.xml" hover="accessor: X[integer n, integer width] = bits(width) value">X</a>[d, 64] = sum;</pstext>
    </ps>
  </ps_section>
</instructionsection>
