slonik/specs/tst_rr.xml

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XML

<?xml version="1.0" encoding="utf-8"?>
<?xml-stylesheet type="text/xsl" encoding="UTF-8" href="iform.xsl" version="1.0"?>
<!DOCTYPE instructionsection PUBLIC "-//ARM//DTD instructionsection //EN" "iform-p.dtd">
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<instructionsection id="TST_rr" title="TST (register-shifted register) -- AArch32" type="instruction">
<docvars>
<docvar key="armarmheading" value="A1" />
<docvar key="instr-class" value="general" />
<docvar key="isa" value="A32" />
<docvar key="mnemonic" value="TST" />
</docvars>
<heading>TST (register-shifted register)</heading>
<desc>
<brief>
<para>Test (register-shifted register)</para>
</brief>
<authored>
<para>Test (register-shifted register) performs a bitwise AND operation on a register value and a register-shifted register value. It updates the condition flags based on the result, and discards the result.</para>
</authored>
<encodingnotes>
<para>For more information about the <arm-defined-word>constrained unpredictable</arm-defined-word> behavior of this instruction, see <xref linkend="CJAEGDJC">Architectural Constraints on UNPREDICTABLE behaviors</xref>.</para>
</encodingnotes>
</desc>
<operationalnotes>
<para>If CPSR.DIT is 1, this instruction has passed its condition execution check, and does not use R15 as either its source or destination:</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="A1" oneof="1" id="iclass_a1" no_encodings="1" isa="A32">
<docvars>
<docvar key="armarmheading" value="A1" />
<docvar key="instr-class" value="general" />
<docvar key="isa" value="A32" />
<docvar key="mnemonic" value="TST" />
</docvars>
<iclassintro count="1"></iclassintro>
<regdiagram form="32" psname="aarch32/instrs/TST_rr/A1_A.txt" tworows="1">
<box hibit="31" width="4" name="cond" usename="1" settings="4" constraint="!= 1111">
<c colspan="4">!= 1111</c>
</box>
<box hibit="27" width="5" settings="5">
<c>0</c>
<c>0</c>
<c>0</c>
<c>1</c>
<c>0</c>
</box>
<box hibit="22" width="2" name="opc" settings="2">
<c>0</c>
<c>0</c>
</box>
<box hibit="20" settings="1">
<c>1</c>
</box>
<box hibit="19" width="4" name="Rn" usename="1">
<c colspan="4"></c>
</box>
<box hibit="15" settings="1">
<c>(0)</c>
</box>
<box hibit="14" settings="1">
<c>(0)</c>
</box>
<box hibit="13" settings="1">
<c>(0)</c>
</box>
<box hibit="12" settings="1">
<c>(0)</c>
</box>
<box hibit="11" width="4" name="Rs" usename="1">
<c colspan="4"></c>
</box>
<box hibit="7" settings="1">
<c>0</c>
</box>
<box hibit="6" width="2" name="stype" usename="1">
<c colspan="2"></c>
</box>
<box hibit="4" settings="1">
<c>1</c>
</box>
<box hibit="3" width="4" name="Rm" usename="1">
<c colspan="4"></c>
</box>
</regdiagram>
<encoding name="TST_rr_A1" oneofinclass="1" oneof="1" label="A1">
<docvars>
<docvar key="armarmheading" value="A1" />
<docvar key="instr-class" value="general" />
<docvar key="isa" value="A32" />
<docvar key="mnemonic" value="TST" />
</docvars>
<asmtemplate><text>TST</text><text>{</text><a link="sa_c" hover="See {xref{ARMARM_Babbefhf}{Standard assembler syntax fields}}">&lt;c&gt;</a><text>}</text><text>{</text><a link="sa_q" hover="See {xref{ARMARM_Babbefhf}{Standard assembler syntax fields}}">&lt;q&gt;</a><text>}</text><text> </text><a link="sa_rn" hover="First general-purpose source register (field &quot;Rn&quot;)">&lt;Rn&gt;</a><text>, </text><a link="sa_rm" hover="Second general-purpose source register (field &quot;Rm&quot;)">&lt;Rm&gt;</a><text>, </text><a link="sa_type" hover="Type of shift applied to second source register (field &quot;stype&quot;) [ASR,LSL,LSR,ROR]">&lt;type&gt;</a><text> </text><a link="sa_rs" hover="Third general-purpose source register holding a shift amount in its bottom 8 bits (field &quot;Rs&quot;)">&lt;Rs&gt;</a></asmtemplate>
</encoding>
<ps_section howmany="1">
<ps name="aarch32/instrs/TST_rr/A1_A.txt" mylink="aarch32.instrs.TST_rr.A1_A.txt" enclabels="" sections="1" secttype="noheading">
<pstext mayhavelinks="1" section="Decode" rep_section="decode">n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rn); m = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rm); s = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rs);
shift_t = <a link="impl-aarch32.DecodeRegShift.1" file="shared_pseudocode.xml" hover="function: SRType DecodeRegShift(bits(2) srtype)">DecodeRegShift</a>(stype);
if n == 15 || m == 15 || s == 15 then UNPREDICTABLE;</pstext>
</ps>
</ps_section>
</iclass>
</classes>
<explanations scope="all">
<explanation enclist="TST_rr_A1" symboldefcount="1">
<symbol link="sa_c">&lt;c&gt;</symbol>
<account encodedin="">
<intro>
<para>See <xref linkend="Babbefhf">Standard assembler syntax fields</xref>.</para>
</intro>
</account>
</explanation>
<explanation enclist="TST_rr_A1" symboldefcount="1">
<symbol link="sa_q">&lt;q&gt;</symbol>
<account encodedin="">
<intro>
<para>See <xref linkend="Babbefhf">Standard assembler syntax fields</xref>.</para>
</intro>
</account>
</explanation>
<explanation enclist="TST_rr_A1" symboldefcount="1">
<symbol link="sa_rn">&lt;Rn&gt;</symbol>
<account encodedin="Rn">
<intro>
<para>Is the first general-purpose source register, encoded in the "Rn" field.</para>
</intro>
</account>
</explanation>
<explanation enclist="TST_rr_A1" symboldefcount="1">
<symbol link="sa_rm">&lt;Rm&gt;</symbol>
<account encodedin="Rm">
<intro>
<para>Is the second general-purpose source register, encoded in the "Rm" field.</para>
</intro>
</account>
</explanation>
<explanation enclist="TST_rr_A1" symboldefcount="1">
<symbol link="sa_type">&lt;type&gt;</symbol>
<definition encodedin="stype">
<intro>Is the type of shift to be applied to the second source register, </intro>
<table class="valuetable">
<tgroup cols="2">
<thead>
<row>
<entry class="bitfield">stype</entry>
<entry class="symbol">&lt;type&gt;</entry>
</row>
</thead>
<tbody>
<row>
<entry class="bitfield">00</entry>
<entry class="symbol">LSL</entry>
</row>
<row>
<entry class="bitfield">01</entry>
<entry class="symbol">LSR</entry>
</row>
<row>
<entry class="bitfield">10</entry>
<entry class="symbol">ASR</entry>
</row>
<row>
<entry class="bitfield">11</entry>
<entry class="symbol">ROR</entry>
</row>
</tbody>
</tgroup>
</table>
</definition>
</explanation>
<explanation enclist="TST_rr_A1" symboldefcount="1">
<symbol link="sa_rs">&lt;Rs&gt;</symbol>
<account encodedin="Rs">
<intro>
<para>Is the third general-purpose source register holding a shift amount in its bottom 8 bits, encoded in the "Rs" field.</para>
</intro>
</account>
</explanation>
</explanations>
<ps_section howmany="1">
<ps name="aarch32/instrs/TST_rr/Op_A.txt" mylink="execute" enclabels="" sections="1" secttype="Operation">
<pstext mayhavelinks="1" section="Execute" rep_section="execute">if <a link="impl-aarch32.ConditionPassed.0" file="shared_pseudocode.xml" hover="function: boolean ConditionPassed()">ConditionPassed</a>() then
EncodingSpecificOperations();
shift_n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(<a link="impl-aarch32.R.read.1" file="shared_pseudocode.xml" hover="accessor: bits(32) R[integer n]">R</a>[s]&lt;7:0&gt;);
(shifted, carry) = <a link="impl-aarch32.Shift_C.4" file="shared_pseudocode.xml" hover="function: (bits(N), bit) Shift_C(bits(N) value, SRType srtype, integer amount, bit carry_in)">Shift_C</a>(<a link="impl-aarch32.R.read.1" file="shared_pseudocode.xml" hover="accessor: bits(32) R[integer n]">R</a>[m], shift_t, shift_n, PSTATE.C);
result = <a link="impl-aarch32.R.read.1" file="shared_pseudocode.xml" hover="accessor: bits(32) R[integer n]">R</a>[n] AND shifted;
PSTATE.N = result&lt;31&gt;;
PSTATE.Z = <a link="impl-shared.IsZeroBit.1" file="shared_pseudocode.xml" hover="function: bit IsZeroBit(bits(N) x)">IsZeroBit</a>(result);
PSTATE.C = carry;
// PSTATE.V unchanged</pstext>
</ps>
</ps_section>
</instructionsection>