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<instructionsection id="ursra_z_zi" title="URSRA" type="instruction">
  <docvars>
    <docvar key="instr-class" value="sve2" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="URSRA" />
  </docvars>
  <heading>URSRA</heading>
  <desc>
    <brief>Unsigned rounding shift right and accumulate (immediate)</brief>
    <description>
      <para>Shift right by immediate each unsigned element of the source vector, inserting zeroes, and add the rounded intermediate result destructively to the corresponding elements of the addend vector. The immediate shift amount is an unsigned value in the range 1 to number of bits per element. This instruction is unpredicated.</para>
    </description>
    <status>Green</status>
    <predicated>False</predicated>
    <takes_movprfx>True</takes_movprfx>
  </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="URSRA" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <regdiagram form="32" psname="URSRA-Z.ZI-_" tworows="1">
        <box hibit="31" width="8" settings="8">
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
        </box>
        <box hibit="23" width="2" name="tszh" usename="1">
          <c colspan="2"></c>
        </box>
        <box hibit="21" settings="1">
          <c>0</c>
        </box>
        <box hibit="20" width="2" name="tszl" usename="1">
          <c colspan="2"></c>
        </box>
        <box hibit="18" width="3" name="imm3" usename="1">
          <c colspan="3"></c>
        </box>
        <box hibit="15" width="4" settings="4">
          <c>1</c>
          <c>1</c>
          <c>1</c>
          <c>0</c>
        </box>
        <box hibit="11" name="R" usename="1" settings="1">
          <c>1</c>
        </box>
        <box hibit="10" name="U" usename="1" settings="1">
          <c>1</c>
        </box>
        <box hibit="9" width="5" name="Zn" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="4" width="5" name="Zda" usename="1">
          <c colspan="5"></c>
        </box>
      </regdiagram>
      <encoding name="ursra_z_zi_" oneofinclass="1" oneof="1" label="">
        <docvars>
          <docvar key="instr-class" value="sve2" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="URSRA" />
        </docvars>
        <asmtemplate><text>URSRA   </text><a link="sa_zda" hover="Third source and destination scalable vector register (field &quot;Zda&quot;)">&lt;Zda&gt;</a><text>.</text><a link="sa_t" hover="Size specifier (field &quot;tszh:tszl&quot;) [B,D,H,S]">&lt;T&gt;</a><text>, </text><a link="sa_zn" hover="First source scalable vector register (field &quot;Zn&quot;)">&lt;Zn&gt;</a><text>.</text><a link="sa_t" hover="Size specifier (field &quot;tszh:tszl&quot;) [B,D,H,S]">&lt;T&gt;</a><text>, #</text><a link="sa_const" hover="Immediate shift amount [1-number of bits per element] (field &quot;tszh:tszl:imm3&quot;)">&lt;const&gt;</a></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="URSRA-Z.ZI-_" mylink="URSRA-Z.ZI-_" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">if !<a link="impl-aarch64.HaveSVE2.0" file="shared_pseudocode.xml" hover="function: boolean HaveSVE2()">HaveSVE2</a>() &amp;&amp; !<a link="impl-aarch64.HaveSME.0" file="shared_pseudocode.xml" hover="function: boolean HaveSME()">HaveSME</a>() then UNDEFINED;
bits(4) tsize = tszh:tszl;
integer esize;
case tsize of
    when '0000' UNDEFINED;
    when '0001' esize = 8;
    when '001x' esize = 16;
    when '01xx' esize = 32;
    when '1xxx' esize = 64;
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Zn);
integer da = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Zda);
integer shift = (2 * esize) - <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(tsize:imm3);</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="ursra_z_zi_" symboldefcount="1">
      <symbol link="sa_zda">&lt;Zda&gt;</symbol>
      <account encodedin="Zda">
        <intro>
          <para>Is the name of the third source and destination scalable vector register, encoded in the "Zda" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="ursra_z_zi_" symboldefcount="1">
      <symbol link="sa_t">&lt;T&gt;</symbol>
      <definition encodedin="tszh:tszl">
        <intro>Is the size specifier, </intro>
        <table class="valuetable">
          <tgroup cols="3">
            <thead>
              <row>
                <entry class="bitfield">tszh</entry>
                <entry class="bitfield">tszl</entry>
                <entry class="symbol">&lt;T&gt;</entry>
              </row>
            </thead>
            <tbody>
              <row>
                <entry class="bitfield">00</entry>
                <entry class="bitfield">00</entry>
                <entry class="symbol">RESERVED</entry>
              </row>
              <row>
                <entry class="bitfield">00</entry>
                <entry class="bitfield">01</entry>
                <entry class="symbol">B</entry>
              </row>
              <row>
                <entry class="bitfield">00</entry>
                <entry class="bitfield">1x</entry>
                <entry class="symbol">H</entry>
              </row>
              <row>
                <entry class="bitfield">01</entry>
                <entry class="bitfield">xx</entry>
                <entry class="symbol">S</entry>
              </row>
              <row>
                <entry class="bitfield">1x</entry>
                <entry class="bitfield">xx</entry>
                <entry class="symbol">D</entry>
              </row>
            </tbody>
          </tgroup>
        </table>
      </definition>
    </explanation>
    <explanation enclist="ursra_z_zi_" symboldefcount="1">
      <symbol link="sa_zn">&lt;Zn&gt;</symbol>
      <account encodedin="Zn">
        <intro>
          <para>Is the name of the first source scalable vector register, encoded in the "Zn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="ursra_z_zi_" symboldefcount="1">
      <symbol link="sa_const">&lt;const&gt;</symbol>
      <account encodedin="imm3:tszh:tszl">
        <intro>
          <para>Is the immediate shift amount, in the range 1 to number of bits per element, encoded in "tszh:tszl:imm3".</para>
        </intro>
      </account>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="URSRA-Z.ZI-_" mylink="execute" enclabels="" sections="1" secttype="Operation">
      <pstext mayhavelinks="1" section="Execute" rep_section="execute"><a link="impl-aarch64.CheckSVEEnabled.0" file="shared_pseudocode.xml" hover="function: CheckSVEEnabled()">CheckSVEEnabled</a>();
constant integer VL = <a link="impl-aarch64.CurrentVL.read.none" file="shared_pseudocode.xml" hover="accessor: integer CurrentVL">CurrentVL</a>;
constant integer elements = VL DIV esize;
bits(VL) operand1 = <a link="impl-aarch64.Z.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) Z[integer n, integer width]">Z</a>[n, VL];
bits(VL) operand2 = <a link="impl-aarch64.Z.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) Z[integer n, integer width]">Z</a>[da, VL];
bits(VL) result;
integer round_const = 1 &lt;&lt; (shift - 1);

for e = 0 to elements-1
    integer element = (<a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(<a link="impl-shared.Elem.read.3" file="shared_pseudocode.xml" hover="accessor: bits(size) Elem[bits(N) vector, integer e, integer size]">Elem</a>[operand1, e, esize]) + round_const) &gt;&gt; shift;
    <a link="impl-shared.Elem.write.3" file="shared_pseudocode.xml" hover="accessor: Elem[bits(N) &amp;vector, integer e, integer size] = bits(size) value">Elem</a>[result, e, esize] = <a link="impl-shared.Elem.read.3" file="shared_pseudocode.xml" hover="accessor: bits(size) Elem[bits(N) vector, integer e, integer size]">Elem</a>[operand2, e, esize] + element&lt;esize-1:0&gt;;

<a link="impl-aarch64.Z.write.2" file="shared_pseudocode.xml" hover="accessor: Z[integer n, integer width] = bits(width) value">Z</a>[da, VL] = result;</pstext>
    </ps>
  </ps_section>
</instructionsection>
