archived-ballistic/spec/arm64_xml/dup_z_zi.xml

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<instructionsection id="dup_z_zi" title="DUP (indexed)" type="instruction">
  <docvars>
    <docvar key="instr-class" value="sve" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="DUP" />
  </docvars>
  <heading>DUP (indexed)</heading>
  <desc>
    <brief>Broadcast indexed element to vector (unpredicated)</brief>
    <description>
      <para>Unconditionally broadcast the indexed source vector element into each element of the destination vector. This instruction is unpredicated.</para>
      <para>The immediate element index is in the range of 0 to 63 (bytes), 31 (halfwords), 15 (words), 7 (doublewords) or 3 (quadwords). Selecting an element beyond the accessible vector length causes the destination vector to be set to zero.</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="1">
    <alias_list_intro>This instruction is used by the alias </alias_list_intro>
    <aliasref aliaspageid="MOV_dup_z_zi" aliasfile="mov_dup_z_zi.xml" hover="Move indexed element or SIMD&amp;FP scalar to vector (unpredicated)" punct=".">
      <text>MOV (SIMD&amp;FP scalar, unpredicated)</text>
      <aliaspref><a link="impl-shared.BitCount.1" file="shared_pseudocode.xml" hover="function: integer BitCount(bits(N) x)">BitCount</a>(imm2:tsz) == 1</aliaspref>
      <aliaspref><a link="impl-shared.BitCount.1" file="shared_pseudocode.xml" hover="function: integer BitCount(bits(N) x)">BitCount</a>(imm2:tsz) &gt; 1</aliaspref>
    </aliasref>
    <alias_list_outro>
      <text>  See </text>
      <aliastablelink />
      <text> below for details of when the alias is preferred.</text>
    </alias_list_outro>
  </alias_list>
  <classes>
    <iclass name="SVE" oneof="1" id="iclass_sve" no_encodings="1" isa="A64">
      <docvars>
        <docvar key="instr-class" value="sve" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="DUP" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <regdiagram form="32" psname="DUP-Z.Zi-_">
        <box hibit="31" width="8" settings="8">
          <c>0</c>
          <c>0</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="imm2" usename="1">
          <c colspan="2"></c>
        </box>
        <box hibit="21" settings="1">
          <c>1</c>
        </box>
        <box hibit="20" width="5" name="tsz" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="15" width="6" settings="6">
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="9" width="5" name="Zn" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="4" width="5" name="Zd" usename="1">
          <c colspan="5"></c>
        </box>
      </regdiagram>
      <encoding name="dup_z_zi_" oneofinclass="1" oneof="1" label="">
        <docvars>
          <docvar key="instr-class" value="sve" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="DUP" />
        </docvars>
        <asmtemplate><text>DUP     </text><a link="sa_zd" hover="Destination scalable vector register (field &quot;Zd&quot;)">&lt;Zd&gt;</a><text>.</text><a link="sa_t" hover="Size specifier (field &quot;tsz&quot;) [B,D,H,Q,S]">&lt;T&gt;</a><text>, </text><a link="sa_zn" hover="Source scalable vector register (field &quot;Zn&quot;)">&lt;Zn&gt;</a><text>.</text><a link="sa_t" hover="Size specifier (field &quot;tsz&quot;) [B,D,H,Q,S]">&lt;T&gt;</a><text>[</text><a link="sa_imm" hover="Immediate index [0-one less than the number of elements in 512 bits] (field &quot;imm2:tsz&quot;)">&lt;imm&gt;</a><text>]</text></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="DUP-Z.Zi-_" mylink="DUP-Z.Zi-_" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">if !<a link="impl-aarch64.HaveSVE.0" file="shared_pseudocode.xml" hover="function: boolean HaveSVE()">HaveSVE</a>() &amp;&amp; !<a link="impl-aarch64.HaveSME.0" file="shared_pseudocode.xml" hover="function: boolean HaveSME()">HaveSME</a>() then UNDEFINED;
bits(7) imm = imm2:tsz;
integer esize;
integer index;
case tsz of
    when '00000' UNDEFINED;
    when '10000' esize = 128; index = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(imm&lt;6:5&gt;);
    when 'x1000' esize = 64;  index = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(imm&lt;6:4&gt;);
    when 'xx100' esize = 32;  index = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(imm&lt;6:3&gt;);
    when 'xxx10' esize = 16;  index = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(imm&lt;6:2&gt;);
    when 'xxxx1' esize = 8;   index = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(imm&lt;6:1&gt;);
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Zn);
integer d = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Zd);</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="dup_z_zi_" symboldefcount="1">
      <symbol link="sa_zd">&lt;Zd&gt;</symbol>
      <account encodedin="Zd">
        <intro>
          <para>Is the name of the destination scalable vector register, encoded in the "Zd" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="dup_z_zi_" symboldefcount="1">
      <symbol link="sa_t">&lt;T&gt;</symbol>
      <definition encodedin="tsz">
        <intro>Is the size specifier, </intro>
        <table class="valuetable">
          <tgroup cols="2">
            <thead>
              <row>
                <entry class="bitfield">tsz</entry>
                <entry class="symbol">&lt;T&gt;</entry>
              </row>
            </thead>
            <tbody>
              <row>
                <entry class="bitfield">00000</entry>
                <entry class="symbol">RESERVED</entry>
              </row>
              <row>
                <entry class="bitfield">xxxx1</entry>
                <entry class="symbol">B</entry>
              </row>
              <row>
                <entry class="bitfield">xxx10</entry>
                <entry class="symbol">H</entry>
              </row>
              <row>
                <entry class="bitfield">xx100</entry>
                <entry class="symbol">S</entry>
              </row>
              <row>
                <entry class="bitfield">x1000</entry>
                <entry class="symbol">D</entry>
              </row>
              <row>
                <entry class="bitfield">10000</entry>
                <entry class="symbol">Q</entry>
              </row>
            </tbody>
          </tgroup>
        </table>
      </definition>
    </explanation>
    <explanation enclist="dup_z_zi_" symboldefcount="1">
      <symbol link="sa_zn">&lt;Zn&gt;</symbol>
      <account encodedin="Zn">
        <intro>
          <para>Is the name of the source scalable vector register, encoded in the "Zn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="dup_z_zi_" symboldefcount="1">
      <symbol link="sa_imm">&lt;imm&gt;</symbol>
      <account encodedin="imm2:tsz">
        <intro>
          <para>Is the immediate index, in the range 0 to one less than the number of elements in 512 bits, encoded in "imm2:tsz".</para>
        </intro>
      </account>
    </explanation>
  </explanations>
  <aliastablehook anchor="aliasconditions">Alias Conditions</aliastablehook>
  <ps_section howmany="1">
    <ps name="DUP-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 PL = VL DIV 8;
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) result;
bits(esize) element;

if index &gt;= elements then
    element = <a link="impl-shared.Zeros.1" file="shared_pseudocode.xml" hover="function: bits(N) Zeros(integer N)">Zeros</a>(esize);
else
    element = <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, index, esize];
result = <a link="impl-shared.Replicate.2" file="shared_pseudocode.xml" hover="function: bits(M*N) Replicate(bits(M) x, integer N)">Replicate</a>(element, VL DIV esize);

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