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<instructionsection id="smops_za32_pp_zz" title="SMOPS (2-way)" type="instruction">
  <docvars>
    <docvar key="instr-class" value="mortlach2" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="SMOPS" />
  </docvars>
  <heading>SMOPS (2-way)</heading>
  <desc>
    <brief>Signed integer sum of outer products and subtract</brief>
    <description>
      <para>This instruction works with a 32-bit element ZA tile.</para>
      <para>The signed integer sum of outer products and subtract instructions multiply the sub-matrix in the first source vector by the sub-matrix in the second source vector. The first source holds SVL<sub>S</sub>×2 sub-matrix of signed 16-bit integer values, and the second source holds 2×SVL<sub>S</sub> sub-matrix of signed 16-bit integer values.</para>
      <para>Each source vector is independently predicated by a corresponding governing predicate. When a 16-bit source element is inactive, it is treated as having the value 0.</para>
      <para>The resulting SVL<sub>S</sub>×SVL<sub>S</sub> widened 32-bit integer sum of outer products is then destructively subtracted from the 32-bit integer destination tile. This is equivalent to performing a 2-way dot product and subtract from each of the destination tile elements.</para>
      <para>Each 32-bit container of the first source vector holds 2 consecutive column elements of each row of a SVL<sub>S</sub>×2 sub-matrix, and each 32-bit container of the second source vector holds 2 consecutive row elements of each column of a 2×SVL<sub>S</sub> sub-matrix.</para>
    </description>
    <status>Green</status>
    <predicated>True</predicated>
    <uses_dit condition="FEAT_SVE2 is implemented or FEAT_SME is implemented">True</uses_dit>
    <sm_policy>SM_1_only</sm_policy>
    <is_gov_pred_pair>True</is_gov_pred_pair>
  </desc>
  <alias_list howmany="0"></alias_list>
  <classes>
    <iclass name="SME2" oneof="1" id="iclass_mortlach2" no_encodings="1" isa="A64">
      <docvars>
        <docvar key="instr-class" value="mortlach2" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="SMOPS" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <arch_variants>
        <arch_variant name="FEAT_SME2" feature="FEAT_SME2" />
      </arch_variants>
      <regdiagram form="32" psname="SMOPS-ZA32.PP.ZZ-16" tworows="1">
        <box hibit="31" width="2" settings="2">
          <c>1</c>
          <c>0</c>
        </box>
        <box hibit="29" width="5" settings="5">
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="24" name="u0" usename="1" settings="1">
          <c>0</c>
        </box>
        <box hibit="23" width="3" settings="3">
          <c>1</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="20" width="5" name="Zm" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="15" width="3" name="Pm" usename="1">
          <c colspan="3"></c>
        </box>
        <box hibit="12" width="3" name="Pn" usename="1">
          <c colspan="3"></c>
        </box>
        <box hibit="9" width="5" name="Zn" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="4" name="S" usename="1" settings="1">
          <c>1</c>
        </box>
        <box hibit="3" settings="1">
          <c>1</c>
        </box>
        <box hibit="2" settings="1">
          <c>0</c>
        </box>
        <box hibit="1" width="2" name="ZAda" usename="1">
          <c colspan="2"></c>
        </box>
      </regdiagram>
      <encoding name="smops_za32_pp_zz_16" oneofinclass="1" oneof="1" label="">
        <docvars>
          <docvar key="instr-class" value="mortlach2" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="SMOPS" />
        </docvars>
        <asmtemplate><text>SMOPS   </text><a link="sa_zada" hover="ZA tile ZA0-ZA3 (field &quot;ZAda&quot;)">&lt;ZAda&gt;</a><text>.S, </text><a link="sa_pn" hover="First governing scalable predicate register P0-P7 (field &quot;Pn&quot;)">&lt;Pn&gt;</a><text>/M, </text><a link="sa_pm" hover="Second governing scalable predicate register P0-P7 (field &quot;Pm&quot;)">&lt;Pm&gt;</a><text>/M, </text><a link="sa_zn" hover="First source scalable vector register (field &quot;Zn&quot;)">&lt;Zn&gt;</a><text>.H, </text><a link="sa_zm" hover="Second source scalable vector register (field &quot;Zm&quot;)">&lt;Zm&gt;</a><text>.H</text></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="SMOPS-ZA32.PP.ZZ-16" mylink="SMOPS-ZA32.PP.ZZ-16" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">if !<a link="impl-aarch64.HaveSME2.0" file="shared_pseudocode.xml" hover="function: boolean HaveSME2()">HaveSME2</a>() then UNDEFINED;
constant integer esize = 32;
integer a = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pn);
integer b = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pm);
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Zn);
integer m = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Zm);
integer da = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(ZAda);
boolean sub_op = TRUE;
boolean unsigned = FALSE;</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="smops_za32_pp_zz_16" symboldefcount="1">
      <symbol link="sa_zada">&lt;ZAda&gt;</symbol>
      <account encodedin="ZAda">
        <intro>
          <para>Is the name of the ZA tile ZA0-ZA3, encoded in the "ZAda" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="smops_za32_pp_zz_16" symboldefcount="1">
      <symbol link="sa_pn">&lt;Pn&gt;</symbol>
      <account encodedin="Pn">
        <intro>
          <para>Is the name of the first governing scalable predicate register P0-P7, encoded in the "Pn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="smops_za32_pp_zz_16" symboldefcount="1">
      <symbol link="sa_pm">&lt;Pm&gt;</symbol>
      <account encodedin="Pm">
        <intro>
          <para>Is the name of the second governing scalable predicate register P0-P7, encoded in the "Pm" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="smops_za32_pp_zz_16" symboldefcount="1">
      <symbol link="sa_zn">&lt;Zn&gt;</symbol>
      <account encodedin="Zn">
        <intro>
          <para>Is the name of the first source scalable vector register, encoded in the "Zn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="smops_za32_pp_zz_16" symboldefcount="1">
      <symbol link="sa_zm">&lt;Zm&gt;</symbol>
      <account encodedin="Zm">
        <intro>
          <para>Is the name of the second source scalable vector register, encoded in the "Zm" field.</para>
        </intro>
      </account>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="SMOPS-ZA32.PP.ZZ-16" mylink="execute" enclabels="" sections="1" secttype="Operation">
      <pstext mayhavelinks="1" section="Execute" rep_section="execute"><a link="impl-aarch64.CheckStreamingSVEAndZAEnabled.0" file="shared_pseudocode.xml" hover="function: CheckStreamingSVEAndZAEnabled()">CheckStreamingSVEAndZAEnabled</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 dim = VL DIV esize;
bits(PL) mask1 = <a link="impl-aarch64.P.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) P[integer n, integer width]">P</a>[a, PL];
bits(PL) mask2 = <a link="impl-aarch64.P.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) P[integer n, integer width]">P</a>[b, PL];
bits(VL) operand1 = <a link="impl-aarch64.Z.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) Z[integer n, integer width]">Z</a>[n, VL];
bits(VL) operand2 = <a link="impl-aarch64.Z.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) Z[integer n, integer width]">Z</a>[m, VL];
bits(dim*dim*esize) operand3 = <a link="impl-aarch64.ZAtile.read.3" file="shared_pseudocode.xml" hover="accessor: bits(width) ZAtile[integer tile, integer esize, integer width]">ZAtile</a>[da, esize, dim*dim*esize];
bits(dim*dim*esize) result;
integer  prod;

for row = 0 to dim-1
    for col = 0 to dim-1
        bits(esize) sum = <a link="impl-shared.Elem.read.3" file="shared_pseudocode.xml" hover="accessor: bits(size) Elem[bits(N) vector, integer e, integer size]">Elem</a>[operand3, row*dim+col, esize];
        for k = 0 to 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>(mask1, 2*row + k, esize DIV 2) &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>(mask2, 2*col + k, esize DIV 2) then
                prod = (<a link="impl-shared.Int.2" file="shared_pseudocode.xml" hover="function: integer Int(bits(N) x, boolean unsigned)">Int</a>(<a link="impl-shared.Elem.read.3" file="shared_pseudocode.xml" hover="accessor: bits(size) Elem[bits(N) vector, integer e, integer size]">Elem</a>[operand1, 2*row + k, esize DIV 2], unsigned) *
                        <a link="impl-shared.Int.2" file="shared_pseudocode.xml" hover="function: integer Int(bits(N) x, boolean unsigned)">Int</a>(<a link="impl-shared.Elem.read.3" file="shared_pseudocode.xml" hover="accessor: bits(size) Elem[bits(N) vector, integer e, integer size]">Elem</a>[operand2, 2*col + k, esize DIV 2], unsigned));
                if sub_op then prod = -prod;
                sum = sum + prod;

        <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, row*dim+col, esize] = sum;

<a link="impl-aarch64.ZAtile.write.3" file="shared_pseudocode.xml" hover="accessor: ZAtile[integer tile, integer esize, integer width] = bits(width) value">ZAtile</a>[da, esize, dim*dim*esize] = result;</pstext>
    </ps>
  </ps_section>
</instructionsection>
