Files
archived-ballistic/spec/arm64_xml/brkn_p_p_pp.xml
Ronald Caesar 26a677f8b4 decoder: Add ARM specification docs
Signed-off-by: Ronald Caesar <github43132@proton.me>
2025-12-12 18:11:36 -04:00

141 lines
7.2 KiB
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">
<!-- 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="brkn_p_p_pp" title="BRKN" type="instruction">
<docvars>
<docvar key="cond-setting" value="no-s" />
<docvar key="instr-class" value="sve" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="BRKN" />
</docvars>
<heading>BRKN</heading>
<desc>
<brief>Propagate break to next partition</brief>
<description>
<para>If the last active element of the first source predicate is false then set the destination predicate to all-false. Otherwise leaves the destination and second source predicate unchanged. Does not set the condition flags.</para>
</description>
<status>Green</status>
<predicated>True</predicated>
</desc>
<alias_list howmany="0"></alias_list>
<classes>
<iclass name="Not setting the condition flags" oneof="1" id="iclass_no_s" no_encodings="1" isa="A64">
<docvars>
<docvar key="cond-setting" value="no-s" />
<docvar key="instr-class" value="sve" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="BRKN" />
</docvars>
<iclassintro count="1"></iclassintro>
<regdiagram form="32" psname="BRKN-P.P.PP-_" tworows="1">
<box hibit="31" width="9" settings="9">
<c>0</c>
<c>0</c>
<c>1</c>
<c>0</c>
<c>0</c>
<c>1</c>
<c>0</c>
<c>1</c>
<c>0</c>
</box>
<box hibit="22" name="S" usename="1" settings="1">
<c>0</c>
</box>
<box hibit="21" width="8" settings="8">
<c>0</c>
<c>1</c>
<c>1</c>
<c>0</c>
<c>0</c>
<c>0</c>
<c>0</c>
<c>1</c>
</box>
<box hibit="13" width="4" name="Pg" usename="1">
<c colspan="4"></c>
</box>
<box hibit="9" settings="1">
<c>0</c>
</box>
<box hibit="8" width="4" name="Pn" usename="1">
<c colspan="4"></c>
</box>
<box hibit="4" settings="1">
<c>0</c>
</box>
<box hibit="3" width="4" name="Pdm" usename="1">
<c colspan="4"></c>
</box>
</regdiagram>
<encoding name="brkn_p_p_pp_" oneofinclass="1" oneof="1" label="">
<docvars>
<docvar key="cond-setting" value="no-s" />
<docvar key="instr-class" value="sve" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="BRKN" />
</docvars>
<asmtemplate><text>BRKN </text><a link="sa_pdm" hover="Second source and destination scalable predicate register (field &quot;Pdm&quot;)">&lt;Pdm&gt;</a><text>.B, </text><a link="sa_pg" hover="Governing scalable predicate register (field &quot;Pg&quot;)">&lt;Pg&gt;</a><text>/Z, </text><a link="sa_pn" hover="First source scalable predicate register (field &quot;Pn&quot;)">&lt;Pn&gt;</a><text>.B, </text><a link="sa_pdm" hover="Second source and destination scalable predicate register (field &quot;Pdm&quot;)">&lt;Pdm&gt;</a><text>.B</text></asmtemplate>
</encoding>
<ps_section howmany="1">
<ps name="BRKN-P.P.PP-_" mylink="BRKN-P.P.PP-_" enclabels="" sections="1" secttype="noheading">
<pstext mayhavelinks="1" section="Decode" rep_section="decode">if !<a link="impl-aarch64.HaveSVE.0" file="shared_pseudocode.xml" hover="function: boolean HaveSVE()">HaveSVE</a>() &amp;&amp; !<a link="impl-aarch64.HaveSME.0" file="shared_pseudocode.xml" hover="function: boolean HaveSME()">HaveSME</a>() then UNDEFINED;
integer g = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pg);
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pn);
integer dm = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Pdm);
boolean setflags = FALSE;</pstext>
</ps>
</ps_section>
</iclass>
</classes>
<explanations scope="all">
<explanation enclist="brkn_p_p_pp_" symboldefcount="1">
<symbol link="sa_pdm">&lt;Pdm&gt;</symbol>
<account encodedin="Pdm">
<intro>
<para>Is the name of the second source and destination scalable predicate register, encoded in the "Pdm" field.</para>
</intro>
</account>
</explanation>
<explanation enclist="brkn_p_p_pp_" symboldefcount="1">
<symbol link="sa_pg">&lt;Pg&gt;</symbol>
<account encodedin="Pg">
<intro>
<para>Is the name of the governing scalable predicate register, encoded in the "Pg" field.</para>
</intro>
</account>
</explanation>
<explanation enclist="brkn_p_p_pp_" symboldefcount="1">
<symbol link="sa_pn">&lt;Pn&gt;</symbol>
<account encodedin="Pn">
<intro>
<para>Is the name of the first source scalable predicate register, encoded in the "Pn" field.</para>
</intro>
</account>
</explanation>
</explanations>
<ps_section howmany="1">
<ps name="BRKN-P.P.PP-_" mylink="execute" enclabels="" sections="1" secttype="Operation">
<pstext mayhavelinks="1" section="Execute" rep_section="execute"><a link="impl-aarch64.CheckSVEEnabled.0" file="shared_pseudocode.xml" hover="function: CheckSVEEnabled()">CheckSVEEnabled</a>();
constant integer VL = <a link="impl-aarch64.CurrentVL.read.none" file="shared_pseudocode.xml" hover="accessor: integer CurrentVL">CurrentVL</a>;
constant integer PL = VL DIV 8;
bits(PL) mask = <a link="impl-aarch64.P.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) P[integer n, integer width]">P</a>[g, PL];
bits(PL) operand1 = <a link="impl-aarch64.P.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) P[integer n, integer width]">P</a>[n, PL];
bits(PL) operand2 = <a link="impl-aarch64.P.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) P[integer n, integer width]">P</a>[dm, PL];
bits(PL) result;
if <a link="impl-aarch64.LastActive.3" file="shared_pseudocode.xml" hover="function: bit LastActive(bits(N) mask, bits(N) x, integer esize)">LastActive</a>(mask, operand1, 8) == '1' then
result = operand2;
else
result = <a link="impl-shared.Zeros.1" file="shared_pseudocode.xml" hover="function: bits(N) Zeros(integer N)">Zeros</a>(PL);
if setflags then
PSTATE.&lt;N,Z,C,V&gt; = <a link="impl-aarch64.PredTest.3" file="shared_pseudocode.xml" hover="function: bits(4) PredTest(bits(N) mask, bits(N) result, integer esize)">PredTest</a>(<a link="impl-shared.Ones.1" file="shared_pseudocode.xml" hover="function: bits(N) Ones(integer N)">Ones</a>(PL), result, 8);
<a link="impl-aarch64.P.write.2" file="shared_pseudocode.xml" hover="accessor: P[integer n, integer width] = bits(width) value">P</a>[dm, PL] = result;</pstext>
</ps>
</ps_section>
</instructionsection>