archived-ballistic/spec/arm64_xml/cosp_sys.xml

<?xml version="1.0" encoding="utf-8"?>
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<instructionsection id="COSP_SYS" title="COSP -- A64" type="alias">
  <docvars>
    <docvar key="alias_mnemonic" value="COSP" />
    <docvar key="instr-class" value="system" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="SYS" />
  </docvars>
  <heading>COSP</heading>
  <desc>
    <brief>
      <para>Clear Other Speculative Predictions by Context</para>
    </brief>
    <authored>
      <para>Clear Other Speculative Predictions by Context prevents predictions, other than Cache prefetch, Control flow, and Data Value predictions, that predict execution addresses based on information gathered from earlier execution within a particular execution context. Predictions, other than Cache prefetch, Control flow, and Data Value predictions, determined by the actions of code in the target execution context or contexts appearing in program order before the instruction cannot exploitatively control any speculative access occurring after the instruction is complete and synchronized.</para>
    </authored>
  </desc>
  <aliasto refiform="sys.xml" iformid="SYS">SYS</aliasto>
  <classes>
    <iclass name="System" oneof="1" id="iclass_system" no_encodings="1" isa="A64">
      <docvars>
        <docvar key="instr-class" value="system" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="SYS" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <arch_variants>
        <arch_variant name="ARMv8.9" feature="FEAT_SPECRES2" />
      </arch_variants>
      <regdiagram form="32" psname="aarch64/instrs/system/sysops" 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" usename="1" settings="1" psbits="x">
          <c>0</c>
        </box>
        <box hibit="20" width="2" name="op0" settings="2">
          <c>0</c>
          <c>1</c>
        </box>
        <box hibit="18" width="3" name="op1" usename="1" settings="3" psbits="xxx">
          <c>0</c>
          <c>1</c>
          <c>1</c>
        </box>
        <box hibit="15" width="4" name="CRn" usename="1" settings="4" psbits="xxxx">
          <c>0</c>
          <c>1</c>
          <c>1</c>
          <c>1</c>
        </box>
        <box hibit="11" width="4" name="CRm" usename="1" settings="4" psbits="xxxx">
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>1</c>
        </box>
        <box hibit="7" width="3" name="op2" usename="1" settings="3" psbits="xxx">
          <c>1</c>
          <c>1</c>
          <c>0</c>
        </box>
        <box hibit="4" width="5" name="Rt" usename="1">
          <c colspan="5"></c>
        </box>
      </regdiagram>
      <encoding name="COSP_SYS_CR_systeminstrs" oneofinclass="1" oneof="1" label="">
        <docvars>
          <docvar key="alias_mnemonic" value="COSP" />
          <docvar key="instr-class" value="system" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="SYS" />
        </docvars>
        <asmtemplate><text>COSP  RCTX, </text><a link="sa_xt_1" hover="64-bit general-purpose source register (field &quot;Rt&quot;)">&lt;Xt&gt;</a></asmtemplate>
        <equivalent_to>
          <asmtemplate><a href="sys.xml#SYS_CR_systeminstrs">SYS</a><text> #3, C7, C3, #6, </text><a link="sa_xt_1" hover="64-bit general-purpose source register (field &quot;Rt&quot;)">&lt;Xt&gt;</a></asmtemplate>
          <aliascond>Unconditionally</aliascond>
        </equivalent_to>
      </encoding>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="COSP_SYS_CR_systeminstrs" symboldefcount="1">
      <symbol link="sa_xt_1">&lt;Xt&gt;</symbol>
      <account encodedin="Rt">
        <intro>
          <para>Is the 64-bit name of the general-purpose source register, encoded in the "Rt" field.</para>
        </intro>
      </account>
    </explanation>
  </explanations>
</instructionsection>