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<instructionsection id="brkpbs_p_p_pp" title="BRKPBS" type="instruction">
  <docvars>
    <docvar key="cond-setting" value="s" />
    <docvar key="instr-class" value="sve" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="BRKPBS" />
  </docvars>
  <heading>BRKPBS</heading>
  <desc>
    <brief>Break before first true condition, propagating from previous partition and setting the condition flags</brief>
    <description>
      <para>If the last active element of the first source predicate is false then set the destination predicate to all-false. Otherwise sets destination predicate elements up to but not 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="BRKPBS" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <regdiagram form="32" psname="BRKPBS-P.P.PP-_" 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="op" settings="1">
          <c>0</c>
        </box>
        <box hibit="22" name="S" usename="1" settings="1">
          <c>1</c>
        </box>
        <box hibit="21" width="2" settings="2">
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="19" width="4" name="Pm" usename="1">
          <c colspan="4"></c>
        </box>
        <box hibit="15" width="2" settings="2">
          <c>1</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="B" usename="1" settings="1">
          <c>1</c>
        </box>
        <box hibit="3" width="4" name="Pd" usename="1">
          <c colspan="4"></c>
        </box>
      </regdiagram>
      <encoding name="brkpbs_p_p_pp_" 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="BRKPBS" />
        </docvars>
        <asmtemplate><text>BRKPBS  </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="First source scalable predicate register (field &quot;Pn&quot;)">&lt;Pn&gt;</a><text>.B, </text><a link="sa_pm" hover="Second source scalable predicate register (field &quot;Pm&quot;)">&lt;Pm&gt;</a><text>.B</text></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="BRKPBS-P.P.PP-_" mylink="BRKPBS-P.P.PP-_" 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 m = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pm);
integer d = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pd);
boolean setflags = TRUE;</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="brkpbs_p_p_pp_" 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="brkpbs_p_p_pp_" 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="brkpbs_p_p_pp_" symboldefcount="1">
      <symbol link="sa_pn">&lt;Pn&gt;</symbol>
      <account encodedin="Pn">
        <intro>
          <para>Is the name of the first source scalable predicate register, encoded in the "Pn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="brkpbs_p_p_pp_" symboldefcount="1">
      <symbol link="sa_pm">&lt;Pm&gt;</symbol>
      <account encodedin="Pm">
        <intro>
          <para>Is the name of the second source scalable predicate register, encoded in the "Pm" field.</para>
        </intro>
      </account>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="BRKPBS-P.P.PP-_" 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) operand1 = <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>[m, PL];
bits(PL) result;
boolean last = (<a link="impl-aarch64.LastActive.3" file="shared_pseudocode.xml" hover="function: bit LastActive(bits(N) mask, bits(N) x, integer esize)">LastActive</a>(mask, operand1, 8) == '1');

for e = 0 to elements-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, 8) then
        last = last &amp;&amp; (!<a link="impl-aarch64.ActivePredicateElement.3" file="shared_pseudocode.xml" hover="function: boolean ActivePredicateElement(bits(N) pred, integer e, integer esize)">ActivePredicateElement</a>(operand2, e, 8));
        bit pbit = if last 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, 1] = <a link="impl-shared.ZeroExtend.2" file="shared_pseudocode.xml" hover="function: bits(N) ZeroExtend(bits(M) x, integer N)">ZeroExtend</a>(pbit, 1);
    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, 1] = <a link="impl-shared.ZeroExtend.2" file="shared_pseudocode.xml" hover="function: bits(N) ZeroExtend(bits(M) x, integer N)">ZeroExtend</a>('0', 1);

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>
