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<instructionsection id="AUTIA" title="AUTIA, AUTIA1716, AUTIASP, AUTIAZ, AUTIZA -- A64" type="instruction">
  <docvars>
    <docvar key="isa" value="A64" />
  </docvars>
  <heading>AUTIA, AUTIA1716, AUTIASP, AUTIAZ, AUTIZA</heading>
  <desc>
    <brief>
      <para>Authenticate Instruction address, using key A</para>
    </brief>
    <authored>
      <para>Authenticate Instruction address, using key A. This instruction authenticates an instruction address, using a modifier and key A.</para>
      <para>The address is:</para>
      <list type="unordered">
        <listitem><content>In the general-purpose register that is specified by <syntax>&lt;Xd&gt;</syntax> for <instruction>AUTIA</instruction> and <instruction>AUTIZA</instruction>.</content></listitem>
        <listitem><content>In X17, for <instruction>AUTIA1716</instruction>.</content></listitem>
        <listitem><content>In X30, for <instruction>AUTIASP</instruction> and <instruction>AUTIAZ</instruction>.</content></listitem>
      </list>
      <para>The modifier is:</para>
      <list type="unordered">
        <listitem><content>In the general-purpose register or stack pointer that is specified by <syntax>&lt;Xn|SP&gt;</syntax> for <instruction>AUTIA</instruction>.</content></listitem>
        <listitem><content>The value zero, for <instruction>AUTIZA</instruction> and <instruction>AUTIAZ</instruction>.</content></listitem>
        <listitem><content>In X16, for <instruction>AUTIA1716</instruction>.</content></listitem>
        <listitem><content>In SP, for <instruction>AUTIASP</instruction>.</content></listitem>
      </list>
      <para>If the authentication passes, the upper bits of the address are restored to enable subsequent use of the address. For information on behavior if the authentication fails, see <xref>Faulting on pointer authentication</xref>.</para>
    </authored>
  </desc>
  <alias_list howmany="0"></alias_list>
  <classes>
    <classesintro count="2">
      <txt>It has encodings from 2 classes:</txt>
      <a href="#iclass_general">Integer</a>
      <txt> and </txt>
      <a href="#iclass_system">System</a>
    </classesintro>
    <iclass name="Integer" oneof="2" id="iclass_general" no_encodings="2" isa="A64">
      <docvars>
        <docvar key="instr-class" value="general" />
        <docvar key="isa" value="A64" />
      </docvars>
      <iclassintro count="2"></iclassintro>
      <arch_variants>
        <arch_variant name="ARMv8.3" feature="FEAT_PAuth" />
      </arch_variants>
      <regdiagram form="32" psname="aarch64/instrs/integer/pac/autia/dp_1src">
        <box hibit="31" name="sf" settings="1">
          <c>1</c>
        </box>
        <box hibit="30" settings="1">
          <c>1</c>
        </box>
        <box hibit="29" name="S" settings="1">
          <c>0</c>
        </box>
        <box hibit="28" width="8" settings="8">
          <c>1</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
          <c>1</c>
          <c>0</c>
        </box>
        <box hibit="20" width="5" name="opcode2" settings="5">
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
        </box>
        <box hibit="15" name="opcode[5]" settings="1">
          <c>0</c>
        </box>
        <box hibit="14" name="opcode[4]" settings="1">
          <c>0</c>
        </box>
        <box hibit="13" name="Z" usename="1">
          <c></c>
        </box>
        <box hibit="12" width="3" name="opcode[2:0]" settings="3">
          <c>1</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="9" width="5" name="Rn" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="4" width="5" name="Rd" usename="1">
          <c colspan="5"></c>
        </box>
      </regdiagram>
      <encoding name="AUTIA_64P_dp_1src" oneofinclass="2" oneof="5" label="AUTIA" bitdiffs="Z == 0">
        <docvars>
          <docvar key="instr-class" value="general" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="AUTIA" />
        </docvars>
        <box hibit="13" width="1" name="Z">
          <c>0</c>
        </box>
        <asmtemplate><text>AUTIA  </text><a link="sa_xd" hover="64-bit general-purpose destination register (field &quot;Rd&quot;)">&lt;Xd&gt;</a><text>, </text><a link="sa_xn_sp" hover="64-bit general-purpose source register or SP (field &quot;Rn&quot;)">&lt;Xn|SP&gt;</a></asmtemplate>
      </encoding>
      <encoding name="AUTIZA_64Z_dp_1src" oneofinclass="2" oneof="5" label="AUTIZA" bitdiffs="Z == 1 &amp;&amp; Rn == 11111">
        <docvars>
          <docvar key="instr-class" value="general" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="AUTIZA" />
        </docvars>
        <box hibit="13" width="1" name="Z">
          <c>1</c>
        </box>
        <box hibit="9" width="5" name="Rn">
          <c>1</c>
          <c>1</c>
          <c>1</c>
          <c>1</c>
          <c>1</c>
        </box>
        <asmtemplate><text>AUTIZA  </text><a link="sa_xd" hover="64-bit general-purpose destination register (field &quot;Rd&quot;)">&lt;Xd&gt;</a></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="aarch64/instrs/integer/pac/autia/dp_1src" mylink="aarch64.instrs.integer.pac.autia.dp_1src" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">boolean source_is_sp = FALSE;
integer d = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rd);
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rn);

if !<a link="impl-aarch64.HavePACExt.0" file="shared_pseudocode.xml" hover="function: boolean HavePACExt()">HavePACExt</a>() then
    UNDEFINED;

if Z == '0' then // AUTIA
    if n == 31 then source_is_sp = TRUE;
else // AUTIZA
    if n != 31 then UNDEFINED;</pstext>
        </ps>
      </ps_section>
    </iclass>
    <iclass name="System" oneof="2" id="iclass_system" no_encodings="3" isa="A64">
      <docvars>
        <docvar key="instr-class" value="system" />
        <docvar key="isa" value="A64" />
      </docvars>
      <iclassintro count="3"></iclassintro>
      <arch_variants>
        <arch_variant name="ARMv8.3" feature="FEAT_PAuth" />
      </arch_variants>
      <regdiagram form="32" psname="aarch64/instrs/integer/pac/autia/hint" tworows="1">
        <box hibit="31" width="10" settings="10">
          <c>1</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="21" name="L" settings="1">
          <c>0</c>
        </box>
        <box hibit="20" width="2" name="op0" settings="2">
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="18" width="3" name="op1" settings="3">
          <c>0</c>
          <c>1</c>
          <c>1</c>
        </box>
        <box hibit="15" width="4" name="CRn" settings="4">
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
        </box>
        <box hibit="11" width="4" name="CRm" usename="1" settings="3" psbits="xxxx">
          <c>0</c>
          <c>0</c>
          <c>x</c>
          <c>1</c>
        </box>
        <box hibit="7" width="3" name="op2" usename="1" settings="2" psbits="xxx">
          <c>1</c>
          <c>0</c>
          <c>x</c>
        </box>
        <box hibit="4" width="5" name="Rt" settings="5">
          <c>1</c>
          <c>1</c>
          <c>1</c>
          <c>1</c>
          <c>1</c>
        </box>
      </regdiagram>
      <encoding name="AUTIA1716_HI_hints" oneofinclass="3" oneof="5" label="AUTIA1716" bitdiffs="CRm == 0001 &amp;&amp; op2 == 100">
        <docvars>
          <docvar key="instr-class" value="system" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="AUTIA1716" />
        </docvars>
        <box hibit="11" width="4" name="CRm">
          <c></c>
          <c></c>
          <c>0</c>
          <c></c>
        </box>
        <box hibit="7" width="3" name="op2">
          <c></c>
          <c></c>
          <c>0</c>
        </box>
        <asmtemplate><text>AUTIA1716</text></asmtemplate>
      </encoding>
      <encoding name="AUTIASP_HI_hints" oneofinclass="3" oneof="5" label="AUTIASP" bitdiffs="CRm == 0011 &amp;&amp; op2 == 101">
        <docvars>
          <docvar key="instr-class" value="system" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="AUTIASP" />
        </docvars>
        <box hibit="11" width="4" name="CRm">
          <c></c>
          <c></c>
          <c>1</c>
          <c></c>
        </box>
        <box hibit="7" width="3" name="op2">
          <c></c>
          <c></c>
          <c>1</c>
        </box>
        <asmtemplate><text>AUTIASP</text></asmtemplate>
      </encoding>
      <encoding name="AUTIAZ_HI_hints" oneofinclass="3" oneof="5" label="AUTIAZ" bitdiffs="CRm == 0011 &amp;&amp; op2 == 100">
        <docvars>
          <docvar key="instr-class" value="system" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="AUTIAZ" />
        </docvars>
        <box hibit="11" width="4" name="CRm">
          <c></c>
          <c></c>
          <c>1</c>
          <c></c>
        </box>
        <box hibit="7" width="3" name="op2">
          <c></c>
          <c></c>
          <c>0</c>
        </box>
        <asmtemplate><text>AUTIAZ</text></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="aarch64/instrs/integer/pac/autia/hint" mylink="aarch64.instrs.integer.pac.autia.hint" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">integer d;
integer n;
boolean source_is_sp = FALSE;

case CRm:op2 of
    when '0011 100' // AUTIAZ
        d = 30;
        n = 31;
    when '0011 101' // AUTIASP
        d = 30;
        source_is_sp = TRUE;
    when '0001 100' // AUTIA1716
        d = 17;
        n = 16;
    when '0001 000' SEE "PACIA";
    when '0001 010' SEE "PACIB";
    when '0001 110' SEE "AUTIB";
    when '0011 00x' SEE "PACIA";
    when '0011 01x' SEE "PACIB";
    when '0011 11x' SEE "AUTIB";
    when '0000 111' SEE "XPACLRI";
    otherwise       SEE "HINT";</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="AUTIA_64P_dp_1src, AUTIZA_64Z_dp_1src" symboldefcount="1">
      <symbol link="sa_xd">&lt;Xd&gt;</symbol>
      <account encodedin="Rd">
        <intro>
          <para>Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="AUTIA_64P_dp_1src" symboldefcount="1">
      <symbol link="sa_xn_sp">&lt;Xn|SP&gt;</symbol>
      <account encodedin="Rn">
        <intro>
          <para>Is the 64-bit name of the general-purpose source register or stack pointer, encoded in the "Rn" field.</para>
        </intro>
      </account>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="aarch64/instrs/integer/pac/autia/dp_1src" mylink="execute" enclabels="" sections="1" secttype="Operation">
      <pstext mayhavelinks="1" section="Execute" rep_section="execute">auth_then_branch = FALSE;

if <a link="impl-aarch64.HavePACExt.0" file="shared_pseudocode.xml" hover="function: boolean HavePACExt()">HavePACExt</a>() then
    if source_is_sp then
        <a link="impl-aarch64.X.write.2" file="shared_pseudocode.xml" hover="accessor: X[integer n, integer width] = bits(width) value">X</a>[d, 64] = AuthIA(X[d, 64], SP[], auth_then_branch);
    else
        <a link="impl-aarch64.X.write.2" file="shared_pseudocode.xml" hover="accessor: X[integer n, integer width] = bits(width) value">X</a>[d, 64] = AuthIA(X[d, 64], X[n, 64], auth_then_branch);</pstext>
    </ps>
  </ps_section>
</instructionsection>
