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archived-ballistic/spec/arm64_xml/subps.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

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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">
<!-- 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="SUBPS" title="SUBPS -- A64" type="instruction">
<docvars>
<docvar key="instr-class" value="general" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="SUBPS" />
</docvars>
<heading>SUBPS</heading>
<desc>
<brief>
<para>Subtract Pointer, setting Flags</para>
</brief>
<authored>
<para>Subtract Pointer, setting Flags subtracts the 56-bit address held in the second source register from the 56-bit address held in the first source register, sign-extends the result to 64-bits, and writes the result to the destination register. It updates the condition flags based on the result of the subtraction.</para>
</authored>
</desc>
<alias_list howmany="1">
<alias_list_intro>This instruction is used by the alias </alias_list_intro>
<aliasref aliaspageid="CMPP_SUBPS" aliasfile="cmpp_subps.xml" hover="Compare with Tag" punct=".">
<text>CMPP</text>
<aliaspref>S == '1' &amp;&amp; Xd == '11111'</aliaspref>
</aliasref>
<alias_list_outro>
<text> See </text>
<aliastablelink />
<text> below for details of when the alias is preferred.</text>
</alias_list_outro>
</alias_list>
<classes>
<iclass name="Integer" oneof="1" id="iclass_general" no_encodings="1" isa="A64">
<docvars>
<docvar key="instr-class" value="general" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="SUBPS" />
</docvars>
<iclassintro count="1"></iclassintro>
<arch_variants>
<arch_variant name="ARMv8.5" feature="FEAT_MTE" />
</arch_variants>
<regdiagram form="32" psname="aarch64/instrs/integer/arithmetic/pointer/mcsubtracttaggedaddresssetflags">
<box hibit="31" name="sf" settings="1">
<c>1</c>
</box>
<box hibit="30" settings="1">
<c>0</c>
</box>
<box hibit="29" name="S" settings="1">
<c>1</c>
</box>
<box hibit="28" width="8" settings="8">
<c>1</c>
<c>1</c>
<c>0</c>
<c>1</c>
<c>0</c>
<c>1</c>
<c>1</c>
<c>0</c>
</box>
<box hibit="20" width="5" name="Xm" usename="1">
<c colspan="5"></c>
</box>
<box hibit="15" name="opcode&lt;5&gt;" settings="1">
<c>0</c>
</box>
<box hibit="14" name="opcode&lt;4&gt;" settings="1">
<c>0</c>
</box>
<box hibit="13" name="opcode&lt;3&gt;" settings="1">
<c>0</c>
</box>
<box hibit="12" name="opcode&lt;2&gt;" settings="1">
<c>0</c>
</box>
<box hibit="11" name="opcode&lt;1&gt;" settings="1">
<c>0</c>
</box>
<box hibit="10" name="opcode&lt;0&gt;" settings="1">
<c>0</c>
</box>
<box hibit="9" width="5" name="Xn" usename="1">
<c colspan="5"></c>
</box>
<box hibit="4" width="5" name="Xd" usename="1">
<c colspan="5"></c>
</box>
</regdiagram>
<encoding name="SUBPS_64S_dp_2src" oneofinclass="1" oneof="1" label="">
<docvars>
<docvar key="instr-class" value="general" />
<docvar key="isa" value="A64" />
<docvar key="mnemonic" value="SUBPS" />
</docvars>
<asmtemplate><text>SUBPS </text><a link="sa_xd" hover="64-bit general-purpose destination register (field &quot;Xd&quot;)">&lt;Xd&gt;</a><text>, </text><a link="sa_xn_sp" hover="First 64-bit source general-purpose register or SP (field &quot;Xn&quot;)">&lt;Xn|SP&gt;</a><text>, </text><a link="sa_xm_sp" hover="Second 64-bit general-purpose source register or SP (field &quot;Xm&quot;)">&lt;Xm|SP&gt;</a></asmtemplate>
</encoding>
<ps_section howmany="1">
<ps name="aarch64/instrs/integer/arithmetic/pointer/mcsubtracttaggedaddresssetflags" mylink="aarch64.instrs.integer.arithmetic.pointer.mcsubtracttaggedaddresssetflags" enclabels="" sections="1" secttype="noheading">
<pstext mayhavelinks="1" section="Decode" rep_section="decode">if !<a link="impl-shared.HaveMTEExt.0" file="shared_pseudocode.xml" hover="function: boolean HaveMTEExt()">HaveMTEExt</a>() then UNDEFINED;
integer d = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Xd);
integer n = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Xn);
integer m = <a link="impl-shared.UInt.1" file="shared_pseudocode.xml" hover="function: integer UInt(bits(N) x)">UInt</a>(Xm);
boolean setflags = TRUE;</pstext>
</ps>
</ps_section>
</iclass>
</classes>
<explanations scope="all">
<explanation enclist="SUBPS_64S_dp_2src" symboldefcount="1">
<symbol link="sa_xd">&lt;Xd&gt;</symbol>
<account encodedin="Xd">
<intro>
<para>Is the 64-bit name of the general-purpose destination register, encoded in the "Xd" field.</para>
</intro>
</account>
</explanation>
<explanation enclist="SUBPS_64S_dp_2src" symboldefcount="1">
<symbol link="sa_xn_sp">&lt;Xn|SP&gt;</symbol>
<account encodedin="Xn">
<intro>
<para>Is the 64-bit name of the first source general-purpose register or stack pointer, encoded in the "Xn" field.</para>
</intro>
</account>
</explanation>
<explanation enclist="SUBPS_64S_dp_2src" symboldefcount="1">
<symbol link="sa_xm_sp">&lt;Xm|SP&gt;</symbol>
<account encodedin="Xm">
<intro>
<para>Is the 64-bit name of the second general-purpose source register or stack pointer, encoded in the "Xm" field.</para>
</intro>
</account>
</explanation>
</explanations>
<aliastablehook anchor="aliasconditions">Alias Conditions</aliastablehook>
<ps_section howmany="1">
<ps name="aarch64/instrs/integer/arithmetic/pointer/mcsubtracttaggedaddresssetflags" mylink="execute" enclabels="" sections="1" secttype="Operation">
<pstext mayhavelinks="1" section="Execute" rep_section="execute">bits(64) operand1 = if n == 31 then <a link="impl-aarch64.SP.read.0" file="shared_pseudocode.xml" hover="accessor: bits(64) SP[]">SP</a>[] else <a link="impl-aarch64.X.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) X[integer n, integer width]">X</a>[n, 64];
bits(64) operand2 = if m == 31 then <a link="impl-aarch64.SP.read.0" file="shared_pseudocode.xml" hover="accessor: bits(64) SP[]">SP</a>[] else <a link="impl-aarch64.X.read.2" file="shared_pseudocode.xml" hover="accessor: bits(width) X[integer n, integer width]">X</a>[m, 64];
operand1 = <a link="impl-shared.SignExtend.2" file="shared_pseudocode.xml" hover="function: bits(N) SignExtend(bits(M) x, integer N)">SignExtend</a>(operand1&lt;55:0&gt;, 64);
operand2 = <a link="impl-shared.SignExtend.2" file="shared_pseudocode.xml" hover="function: bits(N) SignExtend(bits(M) x, integer N)">SignExtend</a>(operand2&lt;55:0&gt;, 64);
bits(64) result;
bits(4) nzcv;
operand2 = NOT(operand2);
(result, nzcv) = <a link="impl-shared.AddWithCarry.3" file="shared_pseudocode.xml" hover="function: (bits(N), bits(4)) AddWithCarry(bits(N) x, bits(N) y, bit carry_in)">AddWithCarry</a>(operand1, operand2, '1');
if setflags then
PSTATE.&lt;N,Z,C,V&gt; = nzcv;
<a link="impl-aarch64.X.write.2" file="shared_pseudocode.xml" hover="accessor: X[integer n, integer width] = bits(width) value">X</a>[d, 64] = result;</pstext>
</ps>
</ps_section>
</instructionsection>