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<instructionsection id="zero_zt_i" title="ZERO (ZT0)" type="instruction">
  <docvars>
    <docvar key="instr-class" value="mortlach2" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="ZERO" />
  </docvars>
  <heading>ZERO (ZT0)</heading>
  <desc>
    <brief>Zero ZT0</brief>
    <description>
      <para>Zero all bytes of the ZT0 register.</para>
      <para>This instruction does not require the PE to be in Streaming SVE mode, and it is expected that this instruction will not experience a significant slowdown due to contention with other PEs that are executing in Streaming SVE mode.</para>
    </description>
    <status>Green</status>
    <predicated>False</predicated>
  </desc>
  <alias_list howmany="0"></alias_list>
  <classes>
    <iclass name="SME2" oneof="1" id="iclass_mortlach2" no_encodings="1" isa="A64">
      <docvars>
        <docvar key="instr-class" value="mortlach2" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="ZERO" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <arch_variants>
        <arch_variant name="FEAT_SME2" feature="FEAT_SME2" />
      </arch_variants>
      <regdiagram form="32" psname="ZERO-ZT.I-_">
        <box hibit="31" width="2" settings="2">
          <c>1</c>
          <c>1</c>
        </box>
        <box hibit="29" width="10" settings="10">
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="19" width="10" settings="10">
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="9" width="6" settings="6">
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="3" name="opc&lt;3&gt;" settings="1">
          <c>0</c>
        </box>
        <box hibit="2" name="opc&lt;2&gt;" settings="1">
          <c>0</c>
        </box>
        <box hibit="1" name="opc&lt;1&gt;" settings="1">
          <c>0</c>
        </box>
        <box hibit="0" name="opc&lt;0&gt;" settings="1">
          <c>1</c>
        </box>
      </regdiagram>
      <encoding name="zero_zt_i_" oneofinclass="1" oneof="1" label="">
        <docvars>
          <docvar key="instr-class" value="mortlach2" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="ZERO" />
        </docvars>
        <asmtemplate><text>ZERO    </text><a>{ ZT0 }</a></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="ZERO-ZT.I-_" mylink="ZERO-ZT.I-_" 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>() then UNDEFINED;</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all"></explanations>
  <ps_section howmany="1">
    <ps name="ZERO-ZT.I-_" mylink="execute" enclabels="" sections="1" secttype="Operation">
      <pstext mayhavelinks="1" section="Execute" rep_section="execute"><a link="impl-aarch64.CheckSMEEnabled.0" file="shared_pseudocode.xml" hover="function: CheckSMEEnabled()">CheckSMEEnabled</a>();
<a link="impl-aarch64.CheckSMEZT0Enabled.0" file="shared_pseudocode.xml" hover="function: CheckSMEZT0Enabled()">CheckSMEZT0Enabled</a>();

if <a link="impl-shared.HaveTME.0" file="shared_pseudocode.xml" hover="function: boolean HaveTME()">HaveTME</a>() &amp;&amp; TSTATE.depth &gt; 0 then
    <a link="impl-aarch64.FailTransaction.2" file="shared_pseudocode.xml" hover="function: FailTransaction(TMFailure cause, boolean retry)">FailTransaction</a>(<a link="TMFailure_ERR" file="shared_pseudocode.xml" hover="enumeration TMFailure { TMFailure_CNCL, TMFailure_DBG, TMFailure_ERR, TMFailure_NEST, TMFailure_SIZE, TMFailure_MEM, TMFailure_TRIVIAL, TMFailure_IMP }">TMFailure_ERR</a>, FALSE);

<a link="impl-aarch64.ZT0.write.1" file="shared_pseudocode.xml" hover="accessor: ZT0[integer width] = bits(width) value">ZT0</a>[512] = <a link="impl-shared.Zeros.1" file="shared_pseudocode.xml" hover="function: bits(N) Zeros(integer N)">Zeros</a>(512);</pstext>
    </ps>
  </ps_section>
</instructionsection>
