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<instructionsection id="SETEND" title="SETEND -- AArch32" type="instruction">
  <docvars>
    <docvar key="instr-class" value="general" />
    <docvar key="mnemonic" value="SETEND" />
  </docvars>
  <heading>SETEND</heading>
  <desc>
    <brief>
      <para>Set Endianness</para>
    </brief>
    <authored>
      <para>Set Endianness writes a new value to <xref linkend="BEIDIGBH">PSTATE</xref>.E.</para>
    </authored>
    <encodingnotes>
      <para>For more information about the <arm-defined-word>constrained unpredictable</arm-defined-word> behavior of this instruction, see <xref linkend="CJAEGDJC">Architectural Constraints on UNPREDICTABLE behaviors</xref>.</para>
    </encodingnotes>
  </desc>
  <alias_list howmany="0"></alias_list>
  <classes>
    <classesintro count="2">
      <txt>It has encodings from the following instruction sets:</txt>
      <txt> A32 (</txt>
      <a href="#iclass_a1">A1</a>
      <txt>)</txt>
      <txt> and </txt>
      <txt> T32 (</txt>
      <a href="#iclass_t1">T1</a>
      <txt>)</txt>
      <txt>.</txt>
    </classesintro>
    <iclass name="A1" oneof="2" id="iclass_a1" no_encodings="1" isa="A32">
      <docvars>
        <docvar key="armarmheading" value="A1" />
        <docvar key="instr-class" value="general" />
        <docvar key="isa" value="A32" />
        <docvar key="mnemonic" value="SETEND" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <regdiagram form="32" psname="aarch32/instrs/SETEND/A1_A.txt">
        <box hibit="31" width="12" settings="12">
          <c>1</c>
          <c>1</c>
          <c>1</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="19" width="2" name="imod" settings="2">
          <c>(0)</c>
          <c>(0)</c>
        </box>
        <box hibit="17" name="M" settings="1">
          <c>(0)</c>
        </box>
        <box hibit="16" name="op" settings="1">
          <c>1</c>
        </box>
        <box hibit="15" settings="1">
          <c>(0)</c>
        </box>
        <box hibit="14" settings="1">
          <c>(0)</c>
        </box>
        <box hibit="13" settings="1">
          <c>(0)</c>
        </box>
        <box hibit="12" settings="1">
          <c>(0)</c>
        </box>
        <box hibit="11" settings="1">
          <c>(0)</c>
        </box>
        <box hibit="10" settings="1">
          <c>(0)</c>
        </box>
        <box hibit="9" name="E" usename="1">
          <c></c>
        </box>
        <box hibit="8" name="A" settings="1">
          <c>(0)</c>
        </box>
        <box hibit="7" name="I" settings="1">
          <c>0</c>
        </box>
        <box hibit="6" name="F" settings="1">
          <c>0</c>
        </box>
        <box hibit="5" settings="1">
          <c>0</c>
        </box>
        <box hibit="4" width="5" name="mode" settings="5">
          <c>0</c>
          <c>(0)</c>
          <c>(0)</c>
          <c>(0)</c>
          <c>(0)</c>
        </box>
      </regdiagram>
      <encoding name="SETEND_A1" oneofinclass="1" oneof="2" label="A1">
        <docvars>
          <docvar key="armarmheading" value="A1" />
          <docvar key="instr-class" value="general" />
          <docvar key="isa" value="A32" />
          <docvar key="mnemonic" value="SETEND" />
        </docvars>
        <asmtemplate comment="Cannot be conditional"><text>SETEND</text><text>{</text><a link="sa_q" hover="See {xref{ARMARM_Babbefhf}{Standard assembler syntax fields}}">&lt;q&gt;</a><text>}</text><text> </text><a link="sa_endian_specifier" hover="Endianness to be selected, and the value to be set in PSTATE (field &quot;E&quot;)">&lt;endian_specifier&gt;</a></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="aarch32/instrs/SETEND/A1_A.txt" mylink="aarch32.instrs.SETEND.A1_A.txt" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">set_bigend = (E == '1');</pstext>
        </ps>
      </ps_section>
    </iclass>
    <iclass name="T1" oneof="2" id="iclass_t1" no_encodings="1" isa="T32">
      <docvars>
        <docvar key="armarmheading" value="T1" />
        <docvar key="instr-class" value="general" />
        <docvar key="isa" value="T32" />
        <docvar key="mnemonic" value="SETEND" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <regdiagram form="16" psname="aarch32/instrs/SETEND/T1_A.txt">
        <box hibit="31" width="10" settings="10">
          <c>1</c>
          <c>0</c>
          <c>1</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
        </box>
        <box hibit="21" name="op" settings="1">
          <c>0</c>
        </box>
        <box hibit="20" settings="1">
          <c>(1)</c>
        </box>
        <box hibit="19" name="E" usename="1">
          <c></c>
        </box>
        <box hibit="18" width="3" settings="3">
          <c>(0)</c>
          <c>(0)</c>
          <c>(0)</c>
        </box>
      </regdiagram>
      <encoding name="SETEND_T1" oneofinclass="1" oneof="2" label="T1">
        <docvars>
          <docvar key="armarmheading" value="T1" />
          <docvar key="instr-class" value="general" />
          <docvar key="isa" value="T32" />
          <docvar key="mnemonic" value="SETEND" />
        </docvars>
        <asmtemplate comment="Not permitted in IT block"><text>SETEND</text><text>{</text><a link="sa_q" hover="See {xref{ARMARM_Babbefhf}{Standard assembler syntax fields}}">&lt;q&gt;</a><text>}</text><text> </text><a link="sa_endian_specifier" hover="Endianness to be selected, and the value to be set in PSTATE (field &quot;E&quot;)">&lt;endian_specifier&gt;</a></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="aarch32/instrs/SETEND/T1_A.txt" mylink="aarch32.instrs.SETEND.T1_A.txt" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">set_bigend = (E == '1');
if <a link="impl-aarch32.InITBlock.0" file="shared_pseudocode.xml" hover="function: boolean InITBlock()">InITBlock</a>() then UNPREDICTABLE;</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="SETEND_A1, SETEND_T1" symboldefcount="1">
      <symbol link="sa_q">&lt;q&gt;</symbol>
      <account encodedin="">
        <intro>
          <para>See <xref linkend="Babbefhf">Standard assembler syntax fields</xref>.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="SETEND_A1, SETEND_T1" symboldefcount="1">
      <symbol link="sa_endian_specifier">&lt;endian_specifier&gt;</symbol>
      <definition encodedin="E">
        <intro>Is the endianness to be selected, and the value to be set in PSTATE.E, </intro>
        <table class="valuetable">
          <tgroup cols="2">
            <thead>
              <row>
                <entry class="bitfield">E</entry>
                <entry class="symbol">&lt;endian_specifier&gt;</entry>
              </row>
            </thead>
            <tbody>
              <row>
                <entry class="bitfield">0</entry>
                <entry class="symbol">LE</entry>
              </row>
              <row>
                <entry class="bitfield">1</entry>
                <entry class="symbol">BE</entry>
              </row>
            </tbody>
          </tgroup>
        </table>
      </definition>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="aarch32/instrs/SETEND/Op_A.txt" mylink="execute" enclabels="" sections="1" secttype="Operation">
      <pstext mayhavelinks="1" section="Execute" rep_section="execute">EncodingSpecificOperations();
<a link="AArch32.CheckSETENDEnabled.0" file="shared_pseudocode.xml" hover="function: AArch32.CheckSETENDEnabled()">AArch32.CheckSETENDEnabled</a>();
PSTATE.E = if set_bigend then '1' else '0';</pstext>
    </ps>
  </ps_section>
</instructionsection>
