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<instructionsection id="bfmls_z_p_zzz" title="BFMLS (vectors)" type="instruction">
  <docvars>
    <docvar key="instr-class" value="sve2" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="BFMLS" />
  </docvars>
  <heading>BFMLS (vectors)</heading>
  <desc>
    <brief>BFloat16 floating-point fused multiply-subtract vectors</brief>
    <description>
      <para>Multiply the corresponding active BFloat16 elements of the first and second source vectors and subtract from elements of the third source (addend) vector without intermediate rounding. Destructively place the results in the destination and third source (addend) vector. Inactive elements in the destination vector register remain unmodified.</para>
      <para>This instruction follows SVE2.1 non-widening BFloat16 numerical behaviors.</para>
      <para>ID_AA64ZFR0_EL1.B16B16 indicates whether this instruction is implemented.</para>
    </description>
    <status>Green</status>
    <predicated>True</predicated>
    <takes_movprfx>True</takes_movprfx>
    <takes_pred_movprfx>True</takes_pred_movprfx>
  </desc>
  <alias_list howmany="0"></alias_list>
  <classes>
    <iclass name="SVE2" oneof="1" id="iclass_sve2" no_encodings="1" isa="A64">
      <docvars>
        <docvar key="instr-class" value="sve2" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="BFMLS" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <arch_variants>
        <arch_variant name="FEAT_B16B16" feature="FEAT_B16B16" />
      </arch_variants>
      <regdiagram form="32" psname="BFMLS-Z.P.ZZZ-_" tworows="1">
        <box hibit="31" width="8" settings="8">
          <c>0</c>
          <c>1</c>
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>0</c>
          <c>1</c>
        </box>
        <box hibit="23" name="size&lt;1&gt;" usename="1" settings="1">
          <c>0</c>
        </box>
        <box hibit="22" name="size&lt;0&gt;" usename="1" settings="1">
          <c>0</c>
        </box>
        <box hibit="21" settings="1">
          <c>1</c>
        </box>
        <box hibit="20" width="5" name="Zm" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="15" settings="1">
          <c>0</c>
        </box>
        <box hibit="14" settings="1">
          <c>0</c>
        </box>
        <box hibit="13" name="op" usename="1" settings="1">
          <c>1</c>
        </box>
        <box hibit="12" width="3" name="Pg" usename="1">
          <c colspan="3"></c>
        </box>
        <box hibit="9" width="5" name="Zn" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="4" width="5" name="Zda" usename="1">
          <c colspan="5"></c>
        </box>
      </regdiagram>
      <encoding name="bfmls_z_p_zzz_" oneofinclass="1" oneof="1" label="">
        <docvars>
          <docvar key="instr-class" value="sve2" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="BFMLS" />
        </docvars>
        <asmtemplate><text>BFMLS   </text><a link="sa_zda" hover="Third source and destination scalable vector register (field &quot;Zda&quot;)">&lt;Zda&gt;</a><text>.H, </text><a link="sa_pg" hover="Governing scalable predicate register P0-P7 (field &quot;Pg&quot;)">&lt;Pg&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="BFMLS-Z.P.ZZZ-_" mylink="BFMLS-Z.P.ZZZ-_" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">if !<a link="impl-aarch64.HaveSVEB16B16.0" file="shared_pseudocode.xml" hover="function: boolean HaveSVEB16B16()">HaveSVEB16B16</a>() then UNDEFINED;
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>(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>(Zda);
boolean op1_neg = TRUE;
boolean op3_neg = FALSE;</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="bfmls_z_p_zzz_" symboldefcount="1">
      <symbol link="sa_zda">&lt;Zda&gt;</symbol>
      <account encodedin="Zda">
        <intro>
          <para>Is the name of the third source and destination scalable vector register, encoded in the "Zda" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="bfmls_z_p_zzz_" symboldefcount="1">
      <symbol link="sa_pg">&lt;Pg&gt;</symbol>
      <account encodedin="Pg">
        <intro>
          <para>Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="bfmls_z_p_zzz_" 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="bfmls_z_p_zzz_" 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="BFMLS-Z.P.ZZZ-_" 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 16;
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(VL) operand1 = if <a link="impl-aarch64.AnyActiveElement.2" file="shared_pseudocode.xml" hover="function: boolean AnyActiveElement(bits(N) mask, integer esize)">AnyActiveElement</a>(mask, 16) then <a link="impl-aarch64.Z.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) Z[integer n, integer width]">Z</a>[n, VL] else <a link="impl-shared.Zeros.1" file="shared_pseudocode.xml" hover="function: bits(N) Zeros(integer N)">Zeros</a>(VL);
bits(VL) operand2 = if <a link="impl-aarch64.AnyActiveElement.2" file="shared_pseudocode.xml" hover="function: boolean AnyActiveElement(bits(N) mask, integer esize)">AnyActiveElement</a>(mask, 16) then <a link="impl-aarch64.Z.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) Z[integer n, integer width]">Z</a>[m, VL] else <a link="impl-shared.Zeros.1" file="shared_pseudocode.xml" hover="function: bits(N) Zeros(integer N)">Zeros</a>(VL);
bits(VL) operand3 = <a link="impl-aarch64.Z.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) Z[integer n, integer width]">Z</a>[da, VL];
bits(VL) result;

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, 16) then
        bits(16) element1 = <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, e, 16];
        bits(16) element2 = <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, e, 16];
        bits(16) element3 = <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, e, 16];

        if op1_neg then element1 = <a link="impl-shared.BFNeg.1" file="shared_pseudocode.xml" hover="function: bits(16) BFNeg(bits(16) op)">BFNeg</a>(element1);
        if op3_neg then element3 = <a link="impl-shared.BFNeg.1" file="shared_pseudocode.xml" hover="function: bits(16) BFNeg(bits(16) op)">BFNeg</a>(element3);
        <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, 16] = <a link="impl-shared.BFMulAdd.4" file="shared_pseudocode.xml" hover="function: bits(16) BFMulAdd(bits(16) addend, bits(16) op1, bits(16) op2, FPCRType fpcr)">BFMulAdd</a>(element3, element1, element2, FPCR[]);
    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, 16] = <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, e, 16];

<a link="impl-aarch64.Z.write.2" file="shared_pseudocode.xml" hover="accessor: Z[integer n, integer width] = bits(width) value">Z</a>[da, VL] = result;</pstext>
    </ps>
  </ps_section>
</instructionsection>
