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archived-ballistic/spec/arm64_xml/umull_advsimd_elt.xml
Ronald Caesar 26a677f8b4 decoder: Add ARM specification docs
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<?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">
<!-- Copyright (c) 2010-2022 Arm Limited or its affiliates. All rights reserved. -->
<!-- This document is Non-Confidential. This document may only be used and distributed in accordance with the terms of the agreement entered into by Arm and the party that Arm delivered this document to. -->
<instructionsection id="UMULL_advsimd_elt" title="UMULL, UMULL2 (by element) -- A64" type="instruction">
<docvars>
<docvar key="advsimd-reguse" value="2reg-element" />
<docvar key="instr-class" value="advsimd" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="UMULL" />
</docvars>
<heading>UMULL, UMULL2 (by element)</heading>
<desc>
<brief>
<para>Unsigned Multiply Long (vector, by element)</para>
</brief>
<authored>
<para>Unsigned Multiply Long (vector, by element). This instruction multiplies each vector element in the lower or upper half of the first source SIMD&amp;FP register by the specified vector element of the second source SIMD&amp;FP register, places the results in a vector, and writes the vector to the destination SIMD&amp;FP register. The destination vector elements are twice as long as the elements that are multiplied.</para>
<para>The <instruction>UMULL</instruction> instruction extracts vector elements from the lower half of the first source register. The <instruction>UMULL2</instruction> instruction extracts vector elements from the upper half of the first source register.</para>
<para>Depending on the settings in the <xref linkend="AArch64.cpacr_el1">CPACR_EL1</xref>, <xref linkend="AArch64.cptr_el2">CPTR_EL2</xref>, and <xref linkend="AArch64.cptr_el3">CPTR_EL3</xref> registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped.</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="Vector" oneof="1" id="iclass_2reg_element" no_encodings="1" isa="A64">
<docvars>
<docvar key="advsimd-reguse" value="2reg-element" />
<docvar key="instr-class" value="advsimd" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="UMULL" />
</docvars>
<iclassintro count="1"></iclassintro>
<regdiagram form="32" psname="aarch64/instrs/vector/arithmetic/binary/element/mul/long" tworows="1">
<box hibit="31" settings="1">
<c>0</c>
</box>
<box hibit="30" name="Q" usename="1">
<c></c>
</box>
<box hibit="29" name="U" usename="1" settings="1" psbits="x">
<c>1</c>
</box>
<box hibit="28" width="5" settings="5">
<c>0</c>
<c>1</c>
<c>1</c>
<c>1</c>
<c>1</c>
</box>
<box hibit="23" width="2" name="size" usename="1">
<c colspan="2"></c>
</box>
<box hibit="21" name="L" usename="1">
<c></c>
</box>
<box hibit="20" name="M" usename="1">
<c></c>
</box>
<box hibit="19" width="4" name="Rm" usename="1">
<c colspan="4"></c>
</box>
<box hibit="15" width="4" name="opcode" settings="4">
<c>1</c>
<c>0</c>
<c>1</c>
<c>0</c>
</box>
<box hibit="11" name="H" usename="1">
<c></c>
</box>
<box hibit="10" settings="1">
<c>0</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="UMULL_asimdelem_L" oneofinclass="1" oneof="1" label="">
<docvars>
<docvar key="advsimd-reguse" value="2reg-element" />
<docvar key="instr-class" value="advsimd" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="UMULL" />
</docvars>
<asmtemplate><text>UMULL</text><a link="sa_2" hover="Second and upper half specifier (field &quot;Q&quot;)">{2}</a><text> </text><a link="sa_vd" hover="SIMD&amp;FP destination register (field &quot;Rd&quot;)">&lt;Vd&gt;</a><text>.</text><a link="sa_ta" hover="Arrangement specifier (field &quot;size&quot;) [2D,4S]">&lt;Ta&gt;</a><text>, </text><a link="sa_vn" hover="First SIMD&amp;FP source register (field &quot;Rn&quot;)">&lt;Vn&gt;</a><text>.</text><a link="sa_tb" hover="Arrangement specifier (field &quot;size:Q&quot;) [2S,4H,4S,8H]">&lt;Tb&gt;</a><text>, </text><a link="sa_vm" hover="Second SIMD&amp;FP source register (field &quot;size:M:Rm&quot;)">&lt;Vm&gt;</a><text>.</text><a link="sa_ts" hover="Element size specifier (field &quot;size&quot;) [H,S]">&lt;Ts&gt;</a><text>[</text><a link="sa_index" hover="Element index (field &quot;size:L:H:M&quot;) [H:L,H:L:M]">&lt;index&gt;</a><text>]</text></asmtemplate>
</encoding>
<ps_section howmany="1">
<ps name="aarch64/instrs/vector/arithmetic/binary/element/mul/long" mylink="aarch64.instrs.vector.arithmetic.binary.element.mul.long" enclabels="" sections="1" secttype="noheading">
<pstext mayhavelinks="1" section="Decode" rep_section="decode">integer idxdsize = if H == '1' then 128 else 64;
integer index;
bit Rmhi;
case size of
when '01' index = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(H:L:M); Rmhi = '0';
when '10' index = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(H:L); Rmhi = M;
otherwise UNDEFINED;
integer d = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Rd);
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>(Rmhi:Rm);
integer esize = 8 &lt;&lt; <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(size);
integer datasize = 64;
integer part = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Q);
integer elements = datasize DIV esize;
boolean unsigned = (U == '1');</pstext>
</ps>
</ps_section>
</iclass>
</classes>
<explanations scope="all">
<explanation enclist="UMULL_asimdelem_L" symboldefcount="1">
<symbol link="sa_2">2</symbol>
<definition encodedin="Q">
<intro>Is the second and upper half specifier. If present it causes the operation to be performed on the upper 64 bits of the registers holding the narrower elements, and is </intro>
<table class="valuetable">
<tgroup cols="2">
<thead>
<row>
<entry class="bitfield">Q</entry>
<entry class="symbol">2</entry>
</row>
</thead>
<tbody>
<row>
<entry class="bitfield">0</entry>
<entry class="symbol">[absent]</entry>
</row>
<row>
<entry class="bitfield">1</entry>
<entry class="symbol">[present]</entry>
</row>
</tbody>
</tgroup>
</table>
</definition>
</explanation>
<explanation enclist="UMULL_asimdelem_L" symboldefcount="1">
<symbol link="sa_vd">&lt;Vd&gt;</symbol>
<account encodedin="Rd">
<intro>
<para>Is the name of the SIMD&amp;FP destination register, encoded in the "Rd" field.</para>
</intro>
</account>
</explanation>
<explanation enclist="UMULL_asimdelem_L" symboldefcount="1">
<symbol link="sa_ta">&lt;Ta&gt;</symbol>
<definition encodedin="size">
<intro>Is an arrangement specifier, </intro>
<table class="valuetable">
<tgroup cols="2">
<thead>
<row>
<entry class="bitfield">size</entry>
<entry class="symbol">&lt;Ta&gt;</entry>
</row>
</thead>
<tbody>
<row>
<entry class="bitfield">00</entry>
<entry class="symbol">RESERVED</entry>
</row>
<row>
<entry class="bitfield">01</entry>
<entry class="symbol">4S</entry>
</row>
<row>
<entry class="bitfield">10</entry>
<entry class="symbol">2D</entry>
</row>
<row>
<entry class="bitfield">11</entry>
<entry class="symbol">RESERVED</entry>
</row>
</tbody>
</tgroup>
</table>
</definition>
</explanation>
<explanation enclist="UMULL_asimdelem_L" symboldefcount="1">
<symbol link="sa_vn">&lt;Vn&gt;</symbol>
<account encodedin="Rn">
<intro>
<para>Is the name of the first SIMD&amp;FP source register, encoded in the "Rn" field.</para>
</intro>
</account>
</explanation>
<explanation enclist="UMULL_asimdelem_L" symboldefcount="1">
<symbol link="sa_tb">&lt;Tb&gt;</symbol>
<definition encodedin="size:Q">
<intro>Is an arrangement specifier, </intro>
<table class="valuetable">
<tgroup cols="3">
<thead>
<row>
<entry class="bitfield">size</entry>
<entry class="bitfield">Q</entry>
<entry class="symbol">&lt;Tb&gt;</entry>
</row>
</thead>
<tbody>
<row>
<entry class="bitfield">00</entry>
<entry class="bitfield">x</entry>
<entry class="symbol">RESERVED</entry>
</row>
<row>
<entry class="bitfield">01</entry>
<entry class="bitfield">0</entry>
<entry class="symbol">4H</entry>
</row>
<row>
<entry class="bitfield">01</entry>
<entry class="bitfield">1</entry>
<entry class="symbol">8H</entry>
</row>
<row>
<entry class="bitfield">10</entry>
<entry class="bitfield">0</entry>
<entry class="symbol">2S</entry>
</row>
<row>
<entry class="bitfield">10</entry>
<entry class="bitfield">1</entry>
<entry class="symbol">4S</entry>
</row>
<row>
<entry class="bitfield">11</entry>
<entry class="bitfield">x</entry>
<entry class="symbol">RESERVED</entry>
</row>
</tbody>
</tgroup>
</table>
</definition>
</explanation>
<explanation enclist="UMULL_asimdelem_L" symboldefcount="1">
<symbol link="sa_vm">&lt;Vm&gt;</symbol>
<definition encodedin="size:M:Rm">
<intro>Is the name of the second SIMD&amp;FP source register, </intro>
<table class="valuetable">
<tgroup cols="2">
<thead>
<row>
<entry class="bitfield">size</entry>
<entry class="symbol">&lt;Vm&gt;</entry>
</row>
</thead>
<tbody>
<row>
<entry class="bitfield">00</entry>
<entry class="symbol">RESERVED</entry>
</row>
<row>
<entry class="bitfield">01</entry>
<entry class="symbol">0:Rm</entry>
</row>
<row>
<entry class="bitfield">10</entry>
<entry class="symbol">M:Rm</entry>
</row>
<row>
<entry class="bitfield">11</entry>
<entry class="symbol">RESERVED</entry>
</row>
</tbody>
</tgroup>
</table>
<after> Restricted to V0-V15 when element size &lt;Ts&gt; is H.</after>
</definition>
</explanation>
<explanation enclist="UMULL_asimdelem_L" symboldefcount="1">
<symbol link="sa_ts">&lt;Ts&gt;</symbol>
<definition encodedin="size">
<intro>Is an element size specifier, </intro>
<table class="valuetable">
<tgroup cols="2">
<thead>
<row>
<entry class="bitfield">size</entry>
<entry class="symbol">&lt;Ts&gt;</entry>
</row>
</thead>
<tbody>
<row>
<entry class="bitfield">00</entry>
<entry class="symbol">RESERVED</entry>
</row>
<row>
<entry class="bitfield">01</entry>
<entry class="symbol">H</entry>
</row>
<row>
<entry class="bitfield">10</entry>
<entry class="symbol">S</entry>
</row>
<row>
<entry class="bitfield">11</entry>
<entry class="symbol">RESERVED</entry>
</row>
</tbody>
</tgroup>
</table>
</definition>
</explanation>
<explanation enclist="UMULL_asimdelem_L" symboldefcount="1">
<symbol link="sa_index">&lt;index&gt;</symbol>
<definition encodedin="size:L:H:M">
<intro>Is the element index, </intro>
<table class="valuetable">
<tgroup cols="2">
<thead>
<row>
<entry class="bitfield">size</entry>
<entry class="symbol">&lt;index&gt;</entry>
</row>
</thead>
<tbody>
<row>
<entry class="bitfield">00</entry>
<entry class="symbol">RESERVED</entry>
</row>
<row>
<entry class="bitfield">01</entry>
<entry class="symbol">H:L:M</entry>
</row>
<row>
<entry class="bitfield">10</entry>
<entry class="symbol">H:L</entry>
</row>
<row>
<entry class="bitfield">11</entry>
<entry class="symbol">RESERVED</entry>
</row>
</tbody>
</tgroup>
</table>
</definition>
</explanation>
</explanations>
<ps_section howmany="1">
<ps name="aarch64/instrs/vector/arithmetic/binary/element/mul/long" mylink="execute" enclabels="" sections="1" secttype="Operation">
<pstext mayhavelinks="1" section="Execute" rep_section="execute"><a link="impl-aarch64.CheckFPAdvSIMDEnabled64.0" file="shared_pseudocode.xml" hover="function: CheckFPAdvSIMDEnabled64()">CheckFPAdvSIMDEnabled64</a>();
bits(datasize) operand1 = <a link="impl-aarch64.Vpart.read.3" file="shared_pseudocode.xml" hover="accessor: bits(width) Vpart[integer n, integer part, integer width]">Vpart</a>[n, part, datasize];
bits(idxdsize) operand2 = <a link="impl-aarch64.V.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) V[integer n, integer width]">V</a>[m, idxdsize];
bits(2*datasize) result;
integer element1;
integer element2;
bits(2*esize) product;
element2 = <a link="impl-shared.Int.2" file="shared_pseudocode.xml" hover="function: integer Int(bits(N) x, boolean unsigned)">Int</a>(<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, index, esize], unsigned);
for e = 0 to elements-1
element1 = <a link="impl-shared.Int.2" file="shared_pseudocode.xml" hover="function: integer Int(bits(N) x, boolean unsigned)">Int</a>(<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, esize], unsigned);
product = (element1 * element2)&lt;2*esize-1:0&gt;;
<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, 2*esize] = product;
<a link="impl-aarch64.V.write.2" file="shared_pseudocode.xml" hover="accessor: V[integer n, integer width] = bits(width) value">V</a>[d, 2*datasize] = result;</pstext>
</ps>
</ps_section>
</instructionsection>