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<instructionsection id="brkas_p_p_p" title="BRKAS" type="instruction">
  <docvars>
    <docvar key="cond-setting" value="s" />
    <docvar key="instr-class" value="sve" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="BRKAS" />
  </docvars>
  <heading>BRKAS</heading>
  <desc>
    <brief>Break after first true condition, setting the condition flags</brief>
    <description>
      <para>Sets destination predicate elements up to and including the first active and true source element to true, then sets subsequent elements to false. Inactive elements in the destination predicate register are set to zero. Sets the <arm-defined-word>First</arm-defined-word> (N), <arm-defined-word>None</arm-defined-word> (Z), <arm-defined-word>!Last</arm-defined-word> (C) condition flags based on the predicate result, and the V flag to zero.</para>
    </description>
    <status>Green</status>
    <predicated>True</predicated>
    <affected_by_sme output="NZCV condition flags" />
  </desc>
  <alias_list howmany="0"></alias_list>
  <classes>
    <iclass name="Setting the condition flags" oneof="1" id="iclass_s" no_encodings="1" isa="A64">
      <docvars>
        <docvar key="cond-setting" value="s" />
        <docvar key="instr-class" value="sve" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="BRKAS" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <regdiagram form="32" psname="BRKAS-P.P.P-Z" tworows="1">
        <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" name="B" usename="1" settings="1">
          <c>0</c>
        </box>
        <box hibit="22" name="S" usename="1" settings="1">
          <c>1</c>
        </box>
        <box hibit="21" width="8" settings="8">
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
        </box>
        <box hibit="13" width="4" name="Pg" usename="1">
          <c colspan="4"></c>
        </box>
        <box hibit="9" settings="1">
          <c>0</c>
        </box>
        <box hibit="8" width="4" name="Pn" usename="1">
          <c colspan="4"></c>
        </box>
        <box hibit="4" name="M" usename="1" settings="1">
          <c>0</c>
        </box>
        <box hibit="3" width="4" name="Pd" usename="1">
          <c colspan="4"></c>
        </box>
      </regdiagram>
      <encoding name="brkas_p_p_p_z" oneofinclass="1" oneof="1" label="">
        <docvars>
          <docvar key="cond-setting" value="s" />
          <docvar key="instr-class" value="sve" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="BRKAS" />
        </docvars>
        <asmtemplate><text>BRKAS   </text><a link="sa_pd" hover="Destination scalable predicate register (field &quot;Pd&quot;)">&lt;Pd&gt;</a><text>.B, </text><a link="sa_pg" hover="Governing scalable predicate register (field &quot;Pg&quot;)">&lt;Pg&gt;</a><text>/Z, </text><a link="sa_pn" hover="Source scalable predicate register (field &quot;Pn&quot;)">&lt;Pn&gt;</a><text>.B</text></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="BRKAS-P.P.P-Z" mylink="BRKAS-P.P.P-Z" 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;
constant integer esize = 8;
integer g = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pg);
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pn);
integer d = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pd);
boolean merging = FALSE;
boolean setflags = TRUE;</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="brkas_p_p_p_z" symboldefcount="1">
      <symbol link="sa_pd">&lt;Pd&gt;</symbol>
      <account encodedin="Pd">
        <intro>
          <para>Is the name of the destination scalable predicate register, encoded in the "Pd" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="brkas_p_p_p_z" symboldefcount="1">
      <symbol link="sa_pg">&lt;Pg&gt;</symbol>
      <account encodedin="Pg">
        <intro>
          <para>Is the name of the governing scalable predicate register, encoded in the "Pg" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="brkas_p_p_p_z" symboldefcount="1">
      <symbol link="sa_pn">&lt;Pn&gt;</symbol>
      <account encodedin="Pn">
        <intro>
          <para>Is the name of the source scalable predicate register, encoded in the "Pn" field.</para>
        </intro>
      </account>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="BRKAS-P.P.P-Z" 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(PL) mask = <a link="impl-aarch64.P.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) P[integer n, integer width]">P</a>[g, PL];
bits(PL) operand  = <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) operand2 = <a link="impl-aarch64.P.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) P[integer n, integer width]">P</a>[d, PL];
boolean break = FALSE;
bits(PL) result;
constant integer psize = esize DIV 8;

for e = 0 to elements-1
    boolean element = <a link="impl-aarch64.ActivePredicateElement.3" file="shared_pseudocode.xml" hover="function: boolean ActivePredicateElement(bits(N) pred, integer e, integer esize)">ActivePredicateElement</a>(operand, e, esize);
    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
        bit pbit = if !break then '1' else '0';
        <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, psize] = <a link="impl-shared.ZeroExtend.2" file="shared_pseudocode.xml" hover="function: bits(N) ZeroExtend(bits(M) x, integer N)">ZeroExtend</a>(pbit, psize);
        break = break || element;
    elsif merging then
        bit pbit = <a link="impl-aarch64.PredicateElement.3" file="shared_pseudocode.xml" hover="function: bit PredicateElement(bits(N) pred, integer e, integer esize)">PredicateElement</a>(operand2, e, esize);
        <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, psize] = <a link="impl-shared.ZeroExtend.2" file="shared_pseudocode.xml" hover="function: bits(N) ZeroExtend(bits(M) x, integer N)">ZeroExtend</a>(pbit, psize);
    else
        <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, psize] = <a link="impl-shared.ZeroExtend.2" file="shared_pseudocode.xml" hover="function: bits(N) ZeroExtend(bits(M) x, integer N)">ZeroExtend</a>('0', psize);

if setflags then
    PSTATE.&lt;N,Z,C,V&gt; = <a link="impl-aarch64.PredTest.3" file="shared_pseudocode.xml" hover="function: bits(4) PredTest(bits(N) mask, bits(N) result, integer esize)">PredTest</a>(mask, result, esize);
<a link="impl-aarch64.P.write.2" file="shared_pseudocode.xml" hover="accessor: P[integer n, integer width] = bits(width) value">P</a>[d, PL] = result;</pstext>
    </ps>
  </ps_section>
</instructionsection>
