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<instructionsection id="ABS" title="ABS -- A64" type="instruction">
  <docvars>
    <docvar key="instr-class" value="general" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="ABS" />
  </docvars>
  <heading>ABS</heading>
  <desc>
    <brief>
      <para>Absolute value</para>
    </brief>
    <authored>
      <para>Absolute value computes the absolute value of the signed integer value in the source register, and writes the result to the destination register.</para>
    </authored>
  </desc>
  <operationalnotes>
    <para>If PSTATE.DIT is 1:</para>
    <list type="unordered">
      <listitem><content>The execution time of this instruction is independent of:<list type="unordered"><listitem><content>The values of the data supplied in any of its registers.</content></listitem><listitem><content>The values of the NZCV flags.</content></listitem></list></content></listitem>
      <listitem><content>The response of this instruction to asynchronous exceptions does not vary based on:<list type="unordered"><listitem><content>The values of the data supplied in any of its registers.</content></listitem><listitem><content>The values of the NZCV flags.</content></listitem></list></content></listitem>
    </list>
  </operationalnotes>
  <alias_list howmany="0"></alias_list>
  <classes>
    <iclass name="Integer" oneof="1" id="iclass_general" no_encodings="2" isa="A64">
      <docvars>
        <docvar key="instr-class" value="general" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="ABS" />
      </docvars>
      <iclassintro count="2"></iclassintro>
      <arch_variants>
        <arch_variant name="ARMv8.9" feature="FEAT_CSSC" />
      </arch_variants>
      <regdiagram form="32" psname="aarch64/instrs/integer/arithmetic/unary/abs">
        <box hibit="31" name="sf" usename="1">
          <c></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>0</c>
        </box>
        <box hibit="15" width="6" name="opcode" settings="6">
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</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="ABS_32_dp_1src" oneofinclass="2" oneof="2" label="32-bit" bitdiffs="sf == 0">
        <docvars>
          <docvar key="datatype" value="32" />
          <docvar key="instr-class" value="general" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="ABS" />
        </docvars>
        <box hibit="31" width="1" name="sf">
          <c>0</c>
        </box>
        <asmtemplate><text>ABS  </text><a link="sa_wd" hover="32-bit general-purpose destination register (field &quot;Rd&quot;)">&lt;Wd&gt;</a><text>, </text><a link="sa_wn" hover="32-bit general-purpose source register (field &quot;Rn&quot;)">&lt;Wn&gt;</a></asmtemplate>
      </encoding>
      <encoding name="ABS_64_dp_1src" oneofinclass="2" oneof="2" label="64-bit" bitdiffs="sf == 1">
        <docvars>
          <docvar key="datatype" value="64" />
          <docvar key="instr-class" value="general" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="ABS" />
        </docvars>
        <box hibit="31" width="1" name="sf">
          <c>1</c>
        </box>
        <asmtemplate><text>ABS  </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" hover="64-bit general-purpose source register (field &quot;Rn&quot;)">&lt;Xn&gt;</a></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="aarch64/instrs/integer/arithmetic/unary/abs" mylink="aarch64.instrs.integer.arithmetic.unary.abs" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">if !<a link="impl-shared.HaveCSSC.0" file="shared_pseudocode.xml" hover="function: boolean HaveCSSC()">HaveCSSC</a>() then UNDEFINED;
integer datasize = 32 &lt;&lt; <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(sf);
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rn);
integer d = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rd);</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="ABS_32_dp_1src" symboldefcount="1">
      <symbol link="sa_wd">&lt;Wd&gt;</symbol>
      <account encodedin="Rd">
        <intro>
          <para>Is the 32-bit name of the general-purpose destination register, encoded in the "Rd" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="ABS_32_dp_1src" symboldefcount="1">
      <symbol link="sa_wn">&lt;Wn&gt;</symbol>
      <account encodedin="Rn">
        <intro>
          <para>Is the 32-bit name of the general-purpose source register, encoded in the "Rn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="ABS_64_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="ABS_64_dp_1src" symboldefcount="1">
      <symbol link="sa_xn">&lt;Xn&gt;</symbol>
      <account encodedin="Rn">
        <intro>
          <para>Is the 64-bit name of the general-purpose source register, encoded in the "Rn" field.</para>
        </intro>
      </account>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="aarch64/instrs/integer/arithmetic/unary/abs" mylink="execute" enclabels="" sections="1" secttype="Operation">
      <pstext mayhavelinks="1" section="Execute" rep_section="execute">bits(datasize) operand1 = <a link="impl-aarch64.X.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) X[integer n, integer width]">X</a>[n, datasize];
integer result = <a link="impl-shared.Abs.1" file="shared_pseudocode.xml" hover="function: integer Abs(integer x)">Abs</a>(<a link="impl-shared.SInt.1" file="shared_pseudocode.xml" hover="function: integer SInt(bits(N) x)">SInt</a>(operand1));
<a link="impl-aarch64.X.write.2" file="shared_pseudocode.xml" hover="accessor: X[integer n, integer width] = bits(width) value">X</a>[d, datasize] = result&lt;datasize-1:0&gt;;</pstext>
    </ps>
  </ps_section>
</instructionsection>
