archived-ballistic/spec/arm64_xml/uxtb_ubfm.xml

<?xml version="1.0" encoding="utf-8"?>
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<instructionsection id="UXTB_UBFM" title="UXTB -- A64" type="alias">
  <docvars>
    <docvar key="alias_mnemonic" value="UXTB" />
    <docvar key="bitfield-fill" value="zero-fill" />
    <docvar key="datatype" value="32" />
    <docvar key="instr-class" value="general" />
    <docvar key="isa" value="A64" />
    <docvar key="mnemonic" value="UBFM" />
    <docvar key="source-type" value="src-is-immediate" />
  </docvars>
  <heading>UXTB</heading>
  <desc>
    <brief>
      <para>Unsigned Extend Byte</para>
    </brief>
    <authored>
      <para>Unsigned Extend Byte extracts an 8-bit value from a register, zero-extends it to the size of the 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>
  <aliasto refiform="ubfm.xml" iformid="UBFM">UBFM</aliasto>
  <classes>
    <iclass name="With zeros to left and right" oneof="1" id="iclass_zero_fill" no_encodings="1" isa="A64">
      <docvars>
        <docvar key="bitfield-fill" value="zero-fill" />
        <docvar key="instr-class" value="general" />
        <docvar key="isa" value="A64" />
        <docvar key="mnemonic" value="UBFM" />
      </docvars>
      <iclassintro count="1"></iclassintro>
      <regdiagram form="32" psname="aarch64/instrs/integer/bitfield" tworows="1">
        <box hibit="31" name="sf" usename="1" settings="1" psbits="x">
          <c>0</c>
        </box>
        <box hibit="30" width="2" name="opc" usename="1" settings="2" psbits="xx">
          <c>1</c>
          <c>0</c>
        </box>
        <box hibit="28" width="6" settings="6">
          <c>1</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>1</c>
          <c>0</c>
        </box>
        <box hibit="22" name="N" usename="1" settings="1" psbits="x">
          <c>0</c>
        </box>
        <box hibit="21" width="6" name="immr" usename="1" settings="6" psbits="xxxxxx">
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>0</c>
        </box>
        <box hibit="15" width="6" name="imms" usename="1" settings="6" psbits="xxxxxx">
          <c>0</c>
          <c>0</c>
          <c>0</c>
          <c>1</c>
          <c>1</c>
          <c>1</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="UXTB_UBFM_32M_bitfield" oneofinclass="1" oneof="1" label="32-bit">
        <docvars>
          <docvar key="alias_mnemonic" value="UXTB" />
          <docvar key="bitfield-fill" value="zero-fill" />
          <docvar key="datatype" value="32" />
          <docvar key="instr-class" value="general" />
          <docvar key="isa" value="A64" />
          <docvar key="mnemonic" value="UBFM" />
          <docvar key="source-type" value="src-is-immediate" />
        </docvars>
        <asmtemplate><text>UXTB  </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>
        <equivalent_to>
          <asmtemplate><a href="ubfm.xml#UBFM_32M_bitfield">UBFM</a><text> </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><text>, #0, #7</text></asmtemplate>
          <aliascond>Unconditionally</aliascond>
        </equivalent_to>
      </encoding>
    </iclass>
  </classes>
  <explanations scope="all">
    <explanation enclist="UXTB_UBFM_32M_bitfield" 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="UXTB_UBFM_32M_bitfield" 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>
  </explanations>
</instructionsection>