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<instructionsection id="CCMN_reg" title="CCMN (register) -- A64" type="instruction">
  <docvars>
    <docvar key="instr-class" value="general" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="CCMN" />
  </docvars>
  <heading>CCMN (register)</heading>
  <desc>
    <brief>
      <para>Conditional Compare Negative (register)</para>
    </brief>
    <authored>
      <para>Conditional Compare Negative (register) sets the value of the condition flags to the result of the comparison of a register value and the inverse of another register value if the condition is TRUE, and an immediate value otherwise.</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="CCMN" />
      </docvars>
      <iclassintro count="2"></iclassintro>
      <regdiagram form="32" psname="aarch64/instrs/integer/conditional/compare/register" tworows="1">
        <box hibit="31" name="sf" usename="1">
          <c></c>
        </box>
        <box hibit="30" name="op" usename="1" settings="1" psbits="x">
          <c>0</c>
        </box>
        <box hibit="29" name="S" settings="1">
          <c>1</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>0</c>
          <c>1</c>
          <c>0</c>
        </box>
        <box hibit="20" width="5" name="Rm" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="15" width="4" name="cond" usename="1">
          <c colspan="4"></c>
        </box>
        <box hibit="11" settings="1">
          <c>0</c>
        </box>
        <box hibit="10" name="o2" settings="1">
          <c>0</c>
        </box>
        <box hibit="9" width="5" name="Rn" usename="1">
          <c colspan="5"></c>
        </box>
        <box hibit="4" name="o3" settings="1">
          <c>0</c>
        </box>
        <box hibit="3" width="4" name="nzcv" usename="1">
          <c colspan="4"></c>
        </box>
      </regdiagram>
      <encoding name="CCMN_32_condcmp_reg" 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="CCMN" />
        </docvars>
        <box hibit="31" width="1" name="sf">
          <c>0</c>
        </box>
        <asmtemplate><text>CCMN  </text><a link="sa_wn" hover="First 32-bit general-purpose source register (field &quot;Rn&quot;)">&lt;Wn&gt;</a><text>, </text><a link="sa_wm" hover="Second 32-bit general-purpose source register (field &quot;Rm&quot;)">&lt;Wm&gt;</a><text>, #</text><a link="sa_nzcv" hover="Flag bit specifier, an immediate [0-15], giving the alternative state for 4-bit NZCV condition flags (field &quot;nzcv&quot;)">&lt;nzcv&gt;</a><text>, </text><a link="sa_cond" hover="Standard condition (field &quot;cond&quot;)">&lt;cond&gt;</a></asmtemplate>
      </encoding>
      <encoding name="CCMN_64_condcmp_reg" 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="CCMN" />
        </docvars>
        <box hibit="31" width="1" name="sf">
          <c>1</c>
        </box>
        <asmtemplate><text>CCMN  </text><a link="sa_xn" hover="First 64-bit general-purpose source register (field &quot;Rn&quot;)">&lt;Xn&gt;</a><text>, </text><a link="sa_xm" hover="Second 64-bit general-purpose source register (field &quot;Rm&quot;)">&lt;Xm&gt;</a><text>, #</text><a link="sa_nzcv" hover="Flag bit specifier, an immediate [0-15], giving the alternative state for 4-bit NZCV condition flags (field &quot;nzcv&quot;)">&lt;nzcv&gt;</a><text>, </text><a link="sa_cond" hover="Standard condition (field &quot;cond&quot;)">&lt;cond&gt;</a></asmtemplate>
      </encoding>
      <ps_section howmany="1">
        <ps name="aarch64/instrs/integer/conditional/compare/register" mylink="aarch64.instrs.integer.conditional.compare.register" enclabels="" sections="1" secttype="noheading">
          <pstext mayhavelinks="1" section="Decode" rep_section="decode">integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rn);
integer m = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rm);
integer datasize = if sf == '1' then 64 else 32;
boolean sub_op = (op == '1');
bits(4) condition = cond;
bits(4) flags = nzcv;</pstext>
        </ps>
      </ps_section>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="CCMN_32_condcmp_reg" symboldefcount="1">
      <symbol link="sa_wn">&lt;Wn&gt;</symbol>
      <account encodedin="Rn">
        <intro>
          <para>Is the 32-bit name of the first general-purpose source register, encoded in the "Rn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="CCMN_32_condcmp_reg" symboldefcount="1">
      <symbol link="sa_wm">&lt;Wm&gt;</symbol>
      <account encodedin="Rm">
        <intro>
          <para>Is the 32-bit name of the second general-purpose source register, encoded in the "Rm" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="CCMN_64_condcmp_reg" symboldefcount="1">
      <symbol link="sa_xn">&lt;Xn&gt;</symbol>
      <account encodedin="Rn">
        <intro>
          <para>Is the 64-bit name of the first general-purpose source register, encoded in the "Rn" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="CCMN_64_condcmp_reg" symboldefcount="1">
      <symbol link="sa_xm">&lt;Xm&gt;</symbol>
      <account encodedin="Rm">
        <intro>
          <para>Is the 64-bit name of the second general-purpose source register, encoded in the "Rm" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="CCMN_32_condcmp_reg, CCMN_64_condcmp_reg" symboldefcount="1">
      <symbol link="sa_nzcv">&lt;nzcv&gt;</symbol>
      <account encodedin="nzcv">
        <intro>
          <para>Is the flag bit specifier, an immediate in the range 0 to 15, giving the alternative state for the 4-bit NZCV condition flags, encoded in the "nzcv" field.</para>
        </intro>
      </account>
    </explanation>
    <explanation enclist="CCMN_32_condcmp_reg, CCMN_64_condcmp_reg" symboldefcount="1">
      <symbol link="sa_cond">&lt;cond&gt;</symbol>
      <account encodedin="cond">
        <intro>
          <para>Is one of the standard conditions, encoded in the "cond" field in the standard way.</para>
        </intro>
      </account>
    </explanation>
  </explanations>
  <ps_section howmany="1">
    <ps name="aarch64/instrs/integer/conditional/compare/register" mylink="execute" enclabels="" sections="1" secttype="Operation">
      <pstext mayhavelinks="1" section="Execute" rep_section="execute">if <a link="impl-shared.ConditionHolds.1" file="shared_pseudocode.xml" hover="function: boolean ConditionHolds(bits(4) cond)">ConditionHolds</a>(condition) then
    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];
    bits(datasize) operand2 = <a link="impl-aarch64.X.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) X[integer n, integer width]">X</a>[m, datasize];
    bit carry_in = '0';
    if sub_op then
        operand2 = NOT(operand2);
        carry_in = '1';
    (-, flags) = <a link="impl-shared.AddWithCarry.3" file="shared_pseudocode.xml" hover="function: (bits(N), bits(4)) AddWithCarry(bits(N) x, bits(N) y, bit carry_in)">AddWithCarry</a>(operand1, operand2, carry_in);
PSTATE.&lt;N,Z,C,V&gt; = flags;</pstext>
    </ps>
  </ps_section>
</instructionsection>
