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 <head>
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  <title>P1111R0: Resolutions to NB Comments on the Parallelism TS v2</title>
<style data-fill-with="stylesheet">/******************************************************************************
 *                   Style sheet for the W3C specifications                   *
 *
 * Special classes handled by this style sheet include:
 *
 * Indices
 *   - .toc for the Table of Contents (<ol class="toc">)
 *     + <span class="secno"> for the section numbers
 *   - #toc for the Table of Contents (<nav id="toc">)
 *   - ul.index for Indices (<a href="#ref">term</a><span>, in §N.M</span>)
 *   - table.index for Index Tables (e.g. for properties or elements)
 *
 * Structural Markup
 *   - table.data for general data tables
 *     -> use 'scope' attribute, <colgroup>, <thead>, and <tbody> for best results !
 *     -> use <table class='complex data'> for extra-complex tables
 *     -> use <td class='long'> for paragraph-length cell content
 *     -> use <td class='pre'> when manual line breaks/indentation would help readability
 *   - dl.switch for switch statements
 *   - ol.algorithm for algorithms (helps to visualize nesting)
 *   - .figure and .caption (HTML4) and figure and figcaption (HTML5)
 *     -> .sidefigure for right-floated figures
 *   - ins/del
 *
 * Code
 *   - pre and code
 *
 * Special Sections
 *   - .note       for informative notes             (div, p, span, aside, details)
 *   - .example    for informative examples          (div, p, pre, span)
 *   - .issue      for issues                        (div, p, span)
 *   - .assertion  for assertions                    (div, p, span)
 *   - .advisement for loud normative statements     (div, p, strong)
 *   - .annoying-warning for spec obsoletion notices (div, aside, details)
 *
 * Definition Boxes
 *   - pre.def   for WebIDL definitions
 *   - table.def for tables that define other entities (e.g. CSS properties)
 *   - dl.def    for definition lists that define other entitles (e.g. HTML elements)
 *
 * Numbering
 *   - .secno for section numbers in .toc and headings (<span class='secno'>3.2</span>)
 *   - .marker for source-inserted example/figure/issue numbers (<span class='marker'>Issue 4</span>)
 *   - ::before styled for CSS-generated issue/example/figure numbers:
 *     -> Documents wishing to use this only need to add
 *        figcaption::before,
 *        .caption::before { content: "Figure "  counter(figure) " ";  }
 *        .example::before { content: "Example " counter(example) " "; }
 *        .issue::before   { content: "Issue "   counter(issue) " ";   }
 *
 * Header Stuff (ignore, just don't conflict with these classes)
 *   - .head for the header
 *   - .copyright for the copyright
 *
 * Miscellaneous
 *   - .overlarge for things that should be as wide as possible, even if
 *     that overflows the body text area. This can be used on an item or
 *     on its container, depending on the effect desired.
 *     Note that this styling basically doesn't help at all when printing,
 *     since A4 paper isn't much wider than the max-width here.
 *     It's better to design things to fit into a narrower measure if possible.
 *   - js-added ToC jump links (see fixup.js)
 *
 ******************************************************************************/

/******************************************************************************/
/*                                   Body                                     */
/******************************************************************************/

	body {
		counter-reset: example figure issue;

		/* Layout */
		max-width: 50em;               /* limit line length to 50em for readability   */
		margin: 0 auto;                /* center text within page                     */
		padding: 1.6em 1.5em 2em 50px; /* assume 16px font size for downlevel clients */
		padding: 1.6em 1.5em 2em calc(26px + 1.5em); /* leave space for status flag     */

		/* Typography */
		line-height: 1.5;
		font-family: sans-serif;
		widows: 2;
		orphans: 2;
		word-wrap: break-word;
		overflow-wrap: break-word;
		hyphens: auto;

		/* Colors */
		color: black;
		background: white top left fixed no-repeat;
		background-size: 25px auto;
	}


/******************************************************************************/
/*                         Front Matter & Navigation                          */
/******************************************************************************/

/** Header ********************************************************************/

	div.head { margin-bottom: 1em }
	div.head hr { border-style: solid; }

	div.head h1 {
		font-weight: bold;
		margin: 0 0 .1em;
		font-size: 220%;
	}

	div.head h2 { margin-bottom: 1.5em;}

/** W3C Logo ******************************************************************/

	.head .logo {
		float: right;
		margin: 0.4rem 0 0.2rem .4rem;
	}

	.head img[src*="logos/W3C"] {
		display: block;
		border: solid #1a5e9a;
		border-width: .65rem .7rem .6rem;
		border-radius: .4rem;
		background: #1a5e9a;
		color: white;
		font-weight: bold;
	}

	.head a:hover > img[src*="logos/W3C"],
	.head a:focus > img[src*="logos/W3C"] {
		opacity: .8;
	}

	.head a:active > img[src*="logos/W3C"] {
		background: #c00;
		border-color: #c00;
	}

	/* see also additional rules in Link Styling section */

/** Copyright *****************************************************************/

	p.copyright,
	p.copyright small { font-size: small }

/** Back to Top / ToC Toggle **************************************************/

	@media print {
		#toc-nav {
			display: none;
		}
	}
	@media not print {
		#toc-nav {
			position: fixed;
			z-index: 2;
			bottom: 0; left: 0;
			margin: 0;
			min-width: 1.33em;
			border-top-right-radius: 2rem;
			box-shadow: 0 0 2px;
			font-size: 1.5em;
			color: black;
		}
		#toc-nav > a {
			display: block;
			white-space: nowrap;

			height: 1.33em;
			padding: .1em 0.3em;
			margin: 0;

			background: white;
			box-shadow: 0 0 2px;
			border: none;
			border-top-right-radius: 1.33em;
			background: white;
		}
		#toc-nav > #toc-jump {
			padding-bottom: 2em;
			margin-bottom: -1.9em;
		}

		#toc-nav > a:hover,
		#toc-nav > a:focus {
			background: #f8f8f8;
		}
		#toc-nav > a:not(:hover):not(:focus) {
			color: #707070;
		}

		/* statusbar gets in the way on keyboard focus; remove once browsers fix */
		#toc-nav > a[href="#toc"]:not(:hover):focus:last-child {
			padding-bottom: 1.5rem;
		}

		#toc-nav:not(:hover) > a:not(:focus) > span + span {
			/* Ideally this uses :focus-within on #toc-nav */
			display: none;
		}
		#toc-nav > a > span + span {
			padding-right: 0.2em;
		}

		#toc-toggle-inline {
			vertical-align: 0.05em;
			font-size: 80%;
			color: gray;
			color: hsla(203,20%,40%,.7);
			border-style: none;
			background: transparent;
			position: relative;
		}
		#toc-toggle-inline:hover:not(:active),
		#toc-toggle-inline:focus:not(:active) {
			text-shadow: 1px 1px silver;
			top: -1px;
			left: -1px;
		}

		#toc-nav :active {
			color: #C00;
		}
	}

/** ToC Sidebar ***************************************************************/

	/* Floating sidebar */
	@media screen {
		body.toc-sidebar #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			max-width: 80%;
			max-width: calc(100% - 2em - 26px);
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			background: inherit;
			background-color: #f7f8f9;
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
		}
		body.toc-sidebar #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
		}
		body.toc-sidebar #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	/* Hide main scroller when only the ToC is visible anyway */
	@media screen and (max-width: 28em) {
		body.toc-sidebar {
			overflow: hidden;
		}
	}

	/* Sidebar with its own space */
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			background: inherit;
			background-color: #f7f8f9;
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
		}
		body:not(.toc-inline) #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
		}

		body:not(.toc-inline) {
			padding-left: 29em;
		}
		/* See also Overflow section at the bottom */

		body:not(.toc-inline) #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) {
			margin: 0 4em;
		}
	}

/******************************************************************************/
/*                                Sectioning                                  */
/******************************************************************************/

/** Headings ******************************************************************/

	h1, h2, h3, h4, h5, h6, dt {
		page-break-after: avoid;
		page-break-inside: avoid;
		font: 100% sans-serif;   /* Reset all font styling to clear out UA styles */
		font-family: inherit;    /* Inherit the font family. */
		line-height: 1.2;        /* Keep wrapped headings compact */
		hyphens: manual;         /* Hyphenated headings look weird */
	}

	h2, h3, h4, h5, h6 {
		margin-top: 3rem;
	}

	h1, h2, h3 {
		color: #005A9C;
		background: transparent;
	}

	h1 { font-size: 170%; }
	h2 { font-size: 140%; }
	h3 { font-size: 120%; }
	h4 { font-weight: bold; }
	h5 { font-style: italic; }
	h6 { font-variant: small-caps; }
	dt { font-weight: bold; }

/** Subheadings ***************************************************************/

	h1 + h2,
	#subtitle {
		/* #subtitle is a subtitle in an H2 under the H1 */
		margin-top: 0;
	}
	h2 + h3,
	h3 + h4,
	h4 + h5,
	h5 + h6 {
		margin-top: 1.2em; /* = 1 x line-height */
	}

/** Section divider ***********************************************************/

	:not(.head) > hr {
		font-size: 1.5em;
		text-align: center;
		margin: 1em auto;
		height: auto;
		border: transparent solid 0;
		background: transparent;
	}
	:not(.head) > hr::before {
		content: "\2727\2003\2003\2727\2003\2003\2727";
	}

/******************************************************************************/
/*                            Paragraphs and Lists                            */
/******************************************************************************/

	p {
		margin: 1em 0;
	}

	dd > p:first-child,
	li > p:first-child {
		margin-top: 0;
	}

	ul, ol {
		margin-left: 0;
		padding-left: 2em;
	}

	li {
		margin: 0.25em 0 0.5em;
		padding: 0;
	}

	dl dd {
		margin: 0 0 .5em 2em;
	}

	.head dd + dd { /* compact for header */
		margin-top: -.5em;
	}

	/* Style for algorithms */
	ol.algorithm ol:not(.algorithm),
	.algorithm > ol ol:not(.algorithm) {
	 border-left: 0.5em solid #DEF;
	}

	/* Put nice boxes around each algorithm. */
	[data-algorithm]:not(.heading) {
	  padding: .5em;
	  border: thin solid #ddd; border-radius: .5em;
	  margin: .5em calc(-0.5em - 1px);
	}
	[data-algorithm]:not(.heading) > :first-child {
	  margin-top: 0;
	}
	[data-algorithm]:not(.heading) > :last-child {
	  margin-bottom: 0;
	}

	/* Style for switch/case <dl>s */
	dl.switch > dd > ol.only,
	dl.switch > dd > .only > ol {
	 margin-left: 0;
	}
	dl.switch > dd > ol.algorithm,
	dl.switch > dd > .algorithm > ol {
	 margin-left: -2em;
	}
	dl.switch {
	 padding-left: 2em;
	}
	dl.switch > dt {
	 text-indent: -1.5em;
	 margin-top: 1em;
	}
	dl.switch > dt + dt {
	 margin-top: 0;
	}
	dl.switch > dt::before {
	 content: '\21AA';
	 padding: 0 0.5em 0 0;
	 display: inline-block;
	 width: 1em;
	 text-align: right;
	 line-height: 0.5em;
	}

/** Terminology Markup ********************************************************/


/******************************************************************************/
/*                                 Inline Markup                              */
/******************************************************************************/

/** Terminology Markup ********************************************************/
	dfn   { /* Defining instance */
		font-weight: bolder;
	}
	a > i { /* Instance of term */
		font-style: normal;
	}
	dt dfn code, code.idl {
		font-size: medium;
	}
	dfn var {
		font-style: normal;
	}

/** Change Marking ************************************************************/

	del { color: red;  text-decoration: line-through; }
	ins { color: #080; text-decoration: underline;    }

/** Miscellaneous improvements to inline formatting ***************************/

	sup {
		vertical-align: super;
		font-size: 80%
	}

/******************************************************************************/
/*                                    Code                                    */
/******************************************************************************/

/** General monospace/pre rules ***********************************************/

	pre, code, samp {
		font-family: Menlo, Consolas, "DejaVu Sans Mono", Monaco, monospace;
		font-size: .9em;
		page-break-inside: avoid;
		hyphens: none;
		text-transform: none;
	}
	pre code,
	code code {
		font-size: 100%;
	}

	pre {
		margin-top: 1em;
		margin-bottom: 1em;
		overflow: auto;
	}

/** Inline Code fragments *****************************************************/

  /* Do something nice. */

/******************************************************************************/
/*                                    Links                                   */
/******************************************************************************/

/** General Hyperlinks ********************************************************/

	/* We hyperlink a lot, so make it less intrusive */
	a[href] {
		color: #034575;
		text-decoration: none;
		border-bottom: 1px solid #707070;
		/* Need a bit of extending for it to look okay */
		padding: 0 1px 0;
		margin: 0 -1px 0;
	}
	a:visited {
		border-bottom-color: #BBB;
	}

	/* Use distinguishing colors when user is interacting with the link */
	a[href]:focus,
	a[href]:hover {
		background: #f8f8f8;
		background: rgba(75%, 75%, 75%, .25);
		border-bottom-width: 3px;
		margin-bottom: -2px;
	}
	a[href]:active {
		color: #C00;
		border-color: #C00;
	}

	/* Backout above styling for W3C logo */
	.head .logo,
	.head .logo a {
		border: none;
		text-decoration: none;
		background: transparent;
	}

/******************************************************************************/
/*                                    Images                                  */
/******************************************************************************/

	img {
		border-style: none;
	}

	/* For autogen numbers, add
	   .caption::before, figcaption::before { content: "Figure " counter(figure) ". "; }
	*/

	figure, .figure, .sidefigure {
		page-break-inside: avoid;
		text-align: center;
		margin: 2.5em 0;
	}
	.figure img,    .sidefigure img,    figure img,
	.figure object, .sidefigure object, figure object {
		max-width: 100%;
		margin: auto;
	}
	.figure pre, .sidefigure pre, figure pre {
		text-align: left;
		display: table;
		margin: 1em auto;
	}
	.figure table, figure table {
		margin: auto;
	}
	@media screen and (min-width: 20em) {
		.sidefigure {
			float: right;
			width: 50%;
			margin: 0 0 0.5em 0.5em
		}
	}
	.caption, figcaption, caption {
		font-style: italic;
		font-size: 90%;
	}
	.caption::before, figcaption::before, figcaption > .marker {
		font-weight: bold;
	}
	.caption, figcaption {
		counter-increment: figure;
	}

	/* DL list is indented 2em, but figure inside it is not */
	dd > .figure, dd > figure { margin-left: -2em }

/******************************************************************************/
/*                             Colored Boxes                                  */
/******************************************************************************/

	.issue, .note, .example, .assertion, .advisement, blockquote {
		padding: .5em;
		border: .5em;
		border-left-style: solid;
		page-break-inside: avoid;
	}
	span.issue, span.note {
		padding: .1em .5em .15em;
		border-right-style: solid;
	}

	.issue,
	.note,
	.example,
	.advisement,
	.assertion,
	blockquote {
		margin: 1em auto;
	}
	.note  > p:first-child,
	.issue > p:first-child,
	blockquote > :first-child {
		margin-top: 0;
	}
	blockquote > :last-child {
		margin-bottom: 0;
	}

/** Blockquotes ***************************************************************/

	blockquote {
		border-color: silver;
	}

/** Open issue ****************************************************************/

	.issue {
		border-color: #E05252;
		background: #FBE9E9;
		counter-increment: issue;
		overflow: auto;
	}
	.issue::before, .issue > .marker {
		text-transform: uppercase;
		color: #AE1E1E;
		padding-right: 1em;
		text-transform: uppercase;
	}
	/* Add .issue::before { content: "Issue " counter(issue) " "; } for autogen numbers,
	   or use class="marker" to mark up the issue number in source. */

/** Example *******************************************************************/

	.example {
		border-color: #E0CB52;
		background: #FCFAEE;
		counter-increment: example;
		overflow: auto;
		clear: both;
	}
	.example::before, .example > .marker {
		text-transform: uppercase;
		color: #827017;
		min-width: 7.5em;
		display: block;
	}
	/* Add .example::before { content: "Example " counter(example) " "; } for autogen numbers,
	   or use class="marker" to mark up the example number in source. */

/** Non-normative Note ********************************************************/

	.note {
		border-color: #52E052;
		background: #E9FBE9;
		overflow: auto;
	}

	.note::before, .note > .marker,
	details.note > summary::before,
	details.note > summary > .marker {
		text-transform: uppercase;
		display: block;
		color: hsl(120, 70%, 30%);
	}
	/* Add .note::before { content: "Note"; } for autogen label,
	   or use class="marker" to mark up the label in source. */

	details.note > summary {
		display: block;
		color: hsl(120, 70%, 30%);
	}
	details.note[open] > summary {
		border-bottom: 1px silver solid;
	}

/** Assertion Box *************************************************************/
	/*  for assertions in algorithms */

	.assertion {
		border-color: #AAA;
		background: #EEE;
	}

/** Advisement Box ************************************************************/
	/*  for attention-grabbing normative statements */

	.advisement {
		border-color: orange;
		border-style: none solid;
		background: #FFEECC;
	}
	strong.advisement {
		display: block;
		text-align: center;
	}
	.advisement > .marker {
		color: #B35F00;
	}

/** Spec Obsoletion Notice ****************************************************/
	/* obnoxious obsoletion notice for older/abandoned specs. */

	details {
		display: block;
	}
	summary {
		font-weight: bolder;
	}

	.annoying-warning:not(details),
	details.annoying-warning:not([open]) > summary,
	details.annoying-warning[open] {
		background: #fdd;
		color: red;
		font-weight: bold;
		padding: .75em 1em;
		border: thick red;
		border-style: solid;
		border-radius: 1em;
	}
	.annoying-warning :last-child {
		margin-bottom: 0;
	}

@media not print {
	details.annoying-warning[open] {
		position: fixed;
		left: 1em;
		right: 1em;
		bottom: 1em;
		z-index: 1000;
	}
}

	details.annoying-warning:not([open]) > summary {
		text-align: center;
	}

/** Entity Definition Boxes ***************************************************/

	.def {
		padding: .5em 1em;
		background: #DEF;
		margin: 1.2em 0;
		border-left: 0.5em solid #8CCBF2;
	}

/******************************************************************************/
/*                                    Tables                                  */
/******************************************************************************/

	th, td {
		text-align: left;
		text-align: start;
	}

/** Property/Descriptor Definition Tables *************************************/

	table.def {
		/* inherits .def box styling, see above */
		width: 100%;
		border-spacing: 0;
	}

	table.def td,
	table.def th {
		padding: 0.5em;
		vertical-align: baseline;
		border-bottom: 1px solid #bbd7e9;
	}

	table.def > tbody > tr:last-child th,
	table.def > tbody > tr:last-child td {
		border-bottom: 0;
	}

	table.def th {
		font-style: italic;
		font-weight: normal;
		padding-left: 1em;
		width: 3em;
	}

	/* For when values are extra-complex and need formatting for readability */
	table td.pre {
		white-space: pre-wrap;
	}

	/* A footnote at the bottom of a def table */
	table.def           td.footnote {
		padding-top: 0.6em;
	}
	table.def           td.footnote::before {
		content: " ";
		display: block;
		height: 0.6em;
		width: 4em;
		border-top: thin solid;
	}

/** Data tables (and properly marked-up index tables) *************************/
	/*
		 <table class="data"> highlights structural relationships in a table
		 when correct markup is used (e.g. thead/tbody, th vs. td, scope attribute)

		 Use class="complex data" for particularly complicated tables --
		 (This will draw more lines: busier, but clearer.)

		 Use class="long" on table cells with paragraph-like contents
		 (This will adjust text alignment accordingly.)
		 Alternately use class="longlastcol" on tables, to have the last column assume "long".
	*/

	table {
		word-wrap: normal;
		overflow-wrap: normal;
		hyphens: manual;
	}

	table.data,
	table.index {
		margin: 1em auto;
		border-collapse: collapse;
		border: hidden;
		width: 100%;
	}
	table.data caption,
	table.index caption {
		max-width: 50em;
		margin: 0 auto 1em;
	}

	table.data td,  table.data th,
	table.index td, table.index th {
		padding: 0.5em 1em;
		border-width: 1px;
		border-color: silver;
		border-top-style: solid;
	}

	table.data thead td:empty {
		padding: 0;
		border: 0;
	}

	table.data  thead,
	table.index thead,
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 <body class="h-entry">
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   <p data-fill-with="logo"></p>
   <h1 class="p-name no-ref" id="title">P1111R0<br>Resolutions to NB Comments on the Parallelism TS v2</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Published Proposal, <time class="dt-updated" datetime="2018-06-04">4 June 2018</time></span></h2>
   <div data-fill-with="spec-metadata">
    <dl>
     <dt>This version:
     <dd><a class="u-url" href="http://wg21.link/D1111R0">http://wg21.link/D1111R0</a>
     <dt>Issue Tracking:
     <dd><a href="https://github.com/brycelelbach/wg21_p1111_proposed_resolution_to_nb_comments_on_the_parallelism_ts_v2/issues">GitHub</a>
     <dt>Authors:
     <dd>
      <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:brycelelbach@gmail.com">Bryce Adelstein Lelbach</a> (<span class="p-org org">NVIDIA</span>)
     <dd>
      <dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:m.kretz@gsi.de">Matthias Kretz</a>
     <dt>Audience:
     <dd>SG1, LEWG, LWG
     <dt>Toggle Diffs:
     <dd>
      <label for="hidedel" id="hidedel-label">Hide deleted text</label>
     <dt>Project:
     <dd>ISO JTC1/SC22/WG21: Programming Language C++
    </dl>
   </div>
   <div data-fill-with="warning"></div>
   <hr title="Separator for header">
  </div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li><a href="#ca15-17us11-12ch35"><span class="secno">1</span> <span class="content">CA 15, CA 16, CA 17, US 11, US 12, CH 35</span></a>
    <li><a href="#us37"><span class="secno">2</span> <span class="content">US 37</span></a>
    <li><a href="#us44"><span class="secno">3</span> <span class="content">US 44</span></a>
    <li><a href="#us53"><span class="secno">4</span> <span class="content">US 53</span></a>
    <li><a href="#us3"><span class="secno">5</span> <span class="content">US 3</span></a>
    <li><a href="#us7"><span class="secno">6</span> <span class="content">US 7</span></a>
    <li><a href="#ca4"><span class="secno">7</span> <span class="content">CA 4</span></a>
    <li><a href="#ca8"><span class="secno">8</span> <span class="content">CA 8</span></a>
    <li><a href="#ca5"><span class="secno">9</span> <span class="content">CA 5</span></a>
    <li><a href="#de19de48"><span class="secno">10</span> <span class="content">DE 19, DE 48</span></a>
    <li><a href="#ch21"><span class="secno">11</span> <span class="content">CH 21</span></a>
    <li><a href="#ch23"><span class="secno">12</span> <span class="content">CH 23</span></a>
    <li><a href="#us42-43"><span class="secno">13</span> <span class="content">US 42, US 43</span></a>
    <li><a href="#ch30ch33"><span class="secno">14</span> <span class="content">CH 30, CH 33</span></a>
    <li><a href="#ch38"><span class="secno">15</span> <span class="content">CH 38</span></a>
    <li><a href="#us41us45ch46-47"><span class="secno">16</span> <span class="content">US 41, US 45, CH 46, CH 47</span></a>
    <li><a href="#us50"><span class="secno">17</span> <span class="content">US 50</span></a>
    <li><a href="#us51"><span class="secno">18</span> <span class="content">US 51</span></a>
    <li>
     <a href="#references"><span class="secno"></span> <span class="content">References</span></a>
     <ol class="toc">
      <li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
     </ol>
   </ol>
  </nav>
  <main>
   <p class="note" role="note"><span>NOTE:</span> All wording is relative to <a data-link-type="biblio" href="#biblio-n4744">[N4744]</a>, the Proposed Draft Technical
Specification for version 2 of the C++ Parallelism Technical Specification
(ISO/IEC PTDS 19750).</p>
   <p class="note" role="note"><span>NOTE:</span> Paragraph references are relative to <a data-link-type="biblio" href="#biblio-n4744">[N4744]</a> and do not take paragraph
renumbering into account. In the places where this would be ambiguous,
descriptions of the location are provided instead of paragraph numbers.</p>
   <p class="note" role="note"><span>NOTE:</span> The changes should be applied in order.</p>
   <h2 class="heading settled" data-level="1" id="ca15-17us11-12ch35"><span class="secno">1. </span><span class="content">CA 15, CA 16, CA 17, US 11, US 12, CH 35</span><a class="self-link" href="#ca15-17us11-12ch35"></a></h2>
   <p>Modify [<strong>parallel.simd.whereexpr</strong>] paragraph 12 as follows:</p>
   <blockquote> If the template parameter <code class="highlight"><span class="n">Flags</span></code> is <code class="highlight"><span class="n">vector_aligned_tag</span></code>, <code class="highlight"><span class="n">mem</span></code> shall point to storage aligned by <code class="highlight"><span class="n">memory_alignment_v</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">U</span><span class="o">></span></code>.
If the template parameter <code class="highlight"><span class="n">Flags</span></code> is <code class="highlight"><span class="n">overaligned_tag</span><span class="o">&lt;</span><span class="n">N</span><span class="o">></span></code>, <code class="highlight"><span class="n">mem</span></code> shall point to storage aligned by <code class="highlight"><span class="n">N</span></code>.
If the template parameter <code class="highlight"><span class="n">Flags</span></code> is <code class="highlight"><span class="n">element_aligned_tag</span></code>, <code class="highlight"><span class="n">mem</span></code> shall point to storage aligned by <code class="highlight"><span class="k">alignof</span><span class="p">(</span><span class="n">U</span><span class="p">)</span></code>.
If <code class="highlight"><span class="n">M</span></code> is not <code class="highlight"><span class="kt">bool</span></code>, the largest <span class="del"><span class="math">i</span> ∊ <code class="highlight"><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="n">M</span><span class="o">::</span><span class="n">size</span><span class="p">())</span></code> where <code class="highlight"><span class="n">mask</span><span class="p">[</span><span class="math"><span class="n">i</span></span><span class="p">]</span></code> is <code class="highlight">true</code></span><span class="ins">selected index</span> is less than the number of values pointed to by <code class="highlight"><span class="n">mem</span></code>. </blockquote>
   <p>In [<strong>parallel.simd.reductions</strong>] replace all occurrences of:</p>
   <blockquote> for all <span class="del"><span class="math">i</span> ∊ {<span class="math">j</span> ∊ ℕ<sub>0</sub> ∣ <span class="math">j</span> &lt; <code class="highlight"><span class="n">M</span><span class="o">::</span><span class="n">size</span><span class="p">()</span></code> ⋀ <code class="highlight"><span class="n">mask</span><span class="p">[</span><span class="math"><span class="n">j</span></span><span class="p">]</span></code>}</span> </blockquote>
   <p>with:</p>
   <blockquote> for all <span class="ins">selected indices <span class="math">i</span></span> </blockquote>
   <p>Replace all occurrences of <span class="del">∊</span> preceding a half-open range with <span class="ins">in the range of</span>.</p>
   <p>Replace all remaining occurrences of <span class="del">∊</span> with <span class="ins">∈</span>.</p>
   <p>Replace all occurrences of <span class="del">ℕ<sub>0</sub></span> with <span class="ins">ℕ</span>.</p>
   <p>Replace all occurrences of <span class="del">-th</span> to <span class="ins"><sup>th</sup></span>.</p>
   <p>Replace all occurrences of <code class="highlight"><span class="n">i</span></code> and <code class="highlight"><span class="n">j</span></code> (code font) with <span class="math">i</span> and <span class="math">j</span> (math font) respectively.</p>
   <h2 class="heading settled" data-level="2" id="us37"><span class="secno">2. </span><span class="content">US 37</span><a class="self-link" href="#us37"></a></h2>
   <p>Move paragraphs 4 and 5 of [<strong>parallel.simd.overview</strong>] into a new subsection after [<strong>parallel.simd.overview</strong>]:</p>
   <ins>
    <blockquote>
      <strong>9.3.2 simd width [parallel.simd.width]</strong> 
     <p><code class="highlight"><span class="k">static</span> <span class="k">constexpr</span> <span class="kt">size_t</span> <span class="nf">size</span><span class="p">()</span> <span class="k">noexcept</span><span class="p">;</span></code></p>
     <p><em>Returns:</em> The width of <code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code>.</p>
    </blockquote>
   </ins>
   <p>Move paragraphs 4 and 5 of [<strong>parallel.simd.mask.overview</strong>] into a new subsection after [<strong>parallel.simd.mask.overview</strong>]:</p>
   <ins>
    <blockquote>
      <strong>9.5.2 simd_mask width [parallel.simd.mask.width]</strong> 
     <p><code class="highlight"><span class="k">static</span> <span class="k">constexpr</span> <span class="kt">size_t</span> <span class="nf">size</span><span class="p">()</span> <span class="k">noexcept</span><span class="p">;</span></code></p>
     <p><em>Returns:</em> The width of <code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code>.</p>
    </blockquote>
   </ins>
   <h2 class="heading settled" data-level="3" id="us44"><span class="secno">3. </span><span class="content">US 44</span><a class="self-link" href="#us44"></a></h2>
   <p>Modify [<strong>parallel.references</strong>] paragraph 2 as follows:</p>
   <blockquote> ISO/IEC 14882:2017 is herein called the <i><b>C++ Standard</b></i>. <span class="ins"> References to clauses within the C++ Standard are written as "C++17 §3.2".</span> The library described in ISO/IEC 14882:2017 clauses 20-33 is herein called the <i><b>C++ Standard Library</b></i>.
The C++ Standard Library components described in ISO/IEC 14882:2017 clauses 28, 29.8 and 23.10.10 are herein called the <i><b>C++ Standard Algorithms Library</b></i>. </blockquote>
   <p>Replace all references to the C++ Standard with references in the style "C++17 §3.2":</p>
   <p>Modify [<strong>parallel.simd.ctor</strong>] paragraph 7 as follows:</p>
   <blockquote> if both U and value_type are integral, the integer conversion rank <span class="del">[conv.rank]</span><span class="ins">(C++17 §7.15)</span> of value_type is greater than the integer conversion rank of U. </blockquote>
   <p>Modify [<strong>parallel.simd.ctor</strong>] paragraph 11 as follows:</p>
   <blockquote> Vectorization-unsafe standard library functions may not be invoked by <code class="highlight"><span class="n">gen</span></code> (<span class="del">[algorithms.parallel.exec]</span><span class="ins">C++17 §28.4.3</span>). </blockquote>
   <p>Modify [<strong>parallel.simd.reductions</strong>] paragraph 4 as follows:</p>
   <blockquote>
<pre class="highlight"><span class="k">template</span><span class="o">&lt;</span><span class="k">class</span> <span class="nc">T</span><span class="p">,</span> <span class="k">class</span> <span class="nc">Abi</span><span class="p">,</span> <span class="k">class</span> <span class="nc">BinaryOperation</span> <span class="o">=</span> <span class="n">plus</span><span class="o">&lt;>></span>
<span class="n">T</span> <span class="n">reduce</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>&amp;</span> <span class="n">x</span><span class="p">,</span> <span class="n">BinaryOperation</span> <span class="n">binary_op</span> <span class="o">=</span> <span class="p">{});</span>
</pre>
    <p><em>Requires:</em> <code class="highlight"><span class="n">binary_op</span></code> shall be callable with two arguments of type <code class="highlight"><span class="n">T</span></code> returning <code class="highlight"><span class="n">T</span></code>, or callable
with two arguments of type <code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">A1</span><span class="o">></span></code> returning <code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">A1</span><span class="o">></span></code> for every <code class="highlight"><span class="n">A1</span></code> that is an ABI tag type.</p>
    <p><em>Returns:</em> <code class="highlight"><em><span class="n">GENERALIZED_SUM</span></em><span class="p">(</span><span class="n">binary_op</span><span class="p">,</span> <span class="n">x</span><span class="p">.</span><span class="n">data</span><span class="p">[</span><em><span class="n">i</span></em><span class="p">],</span> <span class="p">...)</span></code> for all <span class="math">i</span> ∈ <code class="highlight"><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="n">size</span><span class="p">())</span></code><span class="ins"> (C++17 §29.2)</span>.</p>
   </blockquote>
   <h2 class="heading settled" data-level="4" id="us53"><span class="secno">4. </span><span class="content">US 53</span><a class="self-link" href="#us53"></a></h2>
   <p>Modify [<strong>parallel.scope</strong>] paragraph 3 as follows:</p>
   <blockquote> The goal of this Technical Specification is to build widespread existing practice for parallelism in the C++ <span class="ins">programming language</span><span class="del">standard algorithms library</span>. It gives advice on extensions to those vendors who wish to provide them. </blockquote>
   <h2 class="heading settled" data-level="5" id="us3"><span class="secno">5. </span><span class="content">US 3</span><a class="self-link" href="#us3"></a></h2>
   <p>Insert a new paragraph after [<strong>parallel.general.namespaces</strong>] p1:</p>
   <ins>
    <blockquote>
      Each header described in this technical specification shall import the contents of <code class="highlight"><span class="n">std</span><span class="o">::</span><span class="n">experimental</span><span class="o">::</span><span class="n">parallelism_v2</span></code> into <code class="highlight"><span class="n">std</span><span class="o">::</span><span class="n">experimental</span></code> as if by 
<pre class="highlight">    <span class="k">namespace</span> <span class="n">std</span><span class="o">::</span><span class="n">experimental</span> <span class="p">{</span>
      <span class="kr">inline</span> <span class="k">namespace</span> <span class="n">parallelism_v2</span> <span class="p">{}</span>
    <span class="p">}</span>
</pre>
    </blockquote>
   </ins>
   <h2 class="heading settled" data-level="6" id="us7"><span class="secno">6. </span><span class="content">US 7</span><a class="self-link" href="#us7"></a></h2>
   <p>Modify [<strong>parallel.alg.ops.synopsis</strong>] as follows:</p>
   <blockquote> <code class="highlight"><span class="c1">// Exposition only: Suppress template argument deduction.</span></code><br> <code class="highlight"><span class="k">template</span><span class="o">&lt;</span><span class="k">class</span> <span class="nc">T</span><span class="o">></span> <span class="k">struct</span> <span class="del"><span class="n">no_deduce</span></span><span class="ins"><span class="n">type_identity</span></span> <span class="p">{</span> <span class="k">using</span> <span class="n">type</span> <span class="o">=</span> <span class="n">T</span><span class="p">;</span> <span class="p">};</span></code><br> <code class="highlight"><span class="k">template</span><span class="o">&lt;</span><span class="k">class</span> <span class="nc">T</span><span class="o">></span> <span class="k">using</span> <span class="del"><span class="n">no_deduce_t</span></span><span class="ins"><span class="n">type_identity_t</span></span> <span class="o">=</span> <span class="k">typename</span> <span class="del"><span class="n">no_deduce</span></span><span class="ins"><span class="n">type_identity</span></span><span class="o">&lt;</span><span class="n">T</span><span class="o">>::</span><span class="n">type</span><span class="p">;</span></code> </blockquote>
   <p>In [<strong>parallel.alg</strong>], replace all occurrences of:</p>
   <blockquote> <span class="del"><code class="highlight"><span class="n">no_deduce_t</span></code></span> </blockquote>
   <p>with:</p>
   <blockquote> <span class="ins"><code class="highlight"><span class="n">type_identity_t</span></code></span> </blockquote>
   <p>In [<strong>parallel.simd</strong>], replace all occurrences of:</p>
   <blockquote> <span class="del"><code class="highlight"><span class="n">nodeduce_t</span></code></span> </blockquote>
   <p>with:</p>
   <blockquote> <span class="ins"><code class="highlight"><span class="n">type_identity_t</span></code></span> </blockquote>
   <h2 class="heading settled" data-level="7" id="ca4"><span class="secno">7. </span><span class="content">CA 4</span><a class="self-link" href="#ca4"></a></h2>
   <p>Remove the column titled "Doc. No." from [<strong>parallel.general.features</strong>] Table 1.</p>
   <h2 class="heading settled" data-level="8" id="ca8"><span class="secno">8. </span><span class="content">CA 8</span><a class="self-link" href="#ca8"></a></h2>
   <p>Modify [<strong>parallel.alg.reductions</strong>] paragraph 3 as follows:</p>
   <blockquote> Modifications to the accumulator by the application of element access functions accrue as
partial results.
At some point before the algorithm returns, the partial results are combined, two at a time, using the reduction object’s combiner operation until a single value remains, which is then assigned back to the live-out object.
[ <em>Note:</em> <span class="del">in</span><span class="ins">In</span> order to produce useful results, modifications to the accumulator should be limited to commutative operations closely related to the combiner operation.
For example if the combiner is <code class="highlight"><span class="n">plus</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code>, incrementing the accumulator would be consistent with the combiner but doubling it or assigning to it would not.
— <em>end note</em> ] </blockquote>
   <h2 class="heading settled" data-level="9" id="ca5"><span class="secno">9. </span><span class="content">CA 5</span><a class="self-link" href="#ca5"></a></h2>
   <p>Modify [<strong>parallel.exceptions.synopsis</strong>] p2 as follows:</p>
   <blockquote>
    <del>The type <code class="highlight"><span class="n">exception_list</span><span class="o">::</span><span class="n">iterator</span></code> fulfills the requirements of <code class="highlight"><span class="n">ForwardIterator</span></code>.</del>
    <ins><code class="highlight"><span class="n">exception_list</span><span class="o">::</span><span class="n">iterator</span></code> is an iterator which meets the forward iterator requirements and has a value type of <code class="highlight"><span class="n">exception_ptr</span></code>.</ins>
   </blockquote>
   <h2 class="heading settled" data-level="10" id="de19de48"><span class="secno">10. </span><span class="content">DE 19, DE 48</span><a class="self-link" href="#de19de48"></a></h2>
   <p>Modify the <code class="highlight"><span class="n">array</span></code>-returning declarations of <code class="highlight"><span class="n">split</span></code> in [<strong>parallel.simd.synopsis</strong>]:</p>
   <blockquote>
<pre class="highlight"><code class="highlight"><span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="kt"><span class="kt">size_t</span></span><span class="p"><span class="p">...</span></span> <span class="n"><span class="n">Sizes</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">T</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span>
  <span class="n"><span class="n">tuple</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">T</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">simd_abi</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">deduce_t</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">T</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Sizes</span></span><span class="o"><span class="o">>></span></span><span class="p"><span class="p">...</span></span><span class="o"><span class="o">></span></span>
    <span class="n"><span class="n">split</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">T</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">>&amp;</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="kt"><span class="kt">size_t</span></span><span class="p"><span class="p">...</span></span> <span class="n"><span class="n">Sizes</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">T</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span>
  <span class="n"><span class="n">tuple</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">T</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">simd_mask_abi</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">deduce_t</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">T</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Sizes</span></span><span class="o"><span class="o">>></span></span><span class="p"><span class="p">...</span></span><span class="o"><span class="o">></span></span>
    <span class="n"><span class="n">split</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">T</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">>&amp;</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">V</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span>
  <span class="n"><span class="n">array</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">V</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">simd_size_v</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">typename</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">value_type</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">></span></span> <span class="o"><span class="o">/</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">size</span></span><span class="p"><span class="p">()</span></span><span class="o"><span class="o">></span></span>
    <span class="n"><span class="n">split</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">typename</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">value_type</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">>&amp;</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">V</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span>
  <span class="n"><span class="n">array</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">V</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">simd_size_v</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">typename</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="ins"><span class="n"><span class="n">simd_type</span></span><span class="o"><span class="o">::</span></span></span><span class="n"><span class="n">value_type</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">></span></span> <span class="o"><span class="o">/</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">size</span></span><span class="p"><span class="p">()</span></span><span class="o"><span class="o">></span></span>
    <span class="n"><span class="n">split</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">typename</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="ins"><span class="n"><span class="n">simd_type</span></span><span class="o"><span class="o">::</span></span></span><span class="n"><span class="n">value_type</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">>&amp;</span></span><span class="p"><span class="p">);</span></span>
</code></pre>
   </blockquote>
   <p>Modify the <code class="highlight"><span class="n">array</span></code>-returning definitions of <code class="highlight"><span class="n">split</span></code> in [<strong>parallel.simd.casts</strong>]:</p>
   <blockquote>
<pre class="highlight"><code class="highlight"><span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">V</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span>
  <span class="n"><span class="n">array</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">V</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">simd_size_v</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">typename</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">value_type</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">></span></span> <span class="o"><span class="o">/</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">size</span></span><span class="p"><span class="p">()</span></span><span class="o"><span class="o">></span></span>
    <span class="n"><span class="n">split</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">typename</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">value_type</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">>&amp;</span></span> <span class="n"><span class="n">x</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">V</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span>
  <span class="n"><span class="n">array</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">V</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">simd_size_v</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">typename</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="ins"><span class="n"><span class="n">simd_type</span></span><span class="o"><span class="o">::</span></span></span><span class="n"><span class="n">value_type</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">></span></span> <span class="o"><span class="o">/</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="n"><span class="n">size</span></span><span class="p"><span class="p">()</span></span><span class="o"><span class="o">></span></span>
    <span class="n"><span class="n">split</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">typename</span></span> <span class="n"><span class="n">V</span></span><span class="o"><span class="o">::</span></span><span class="ins"><span class="n"><span class="n">simd_type</span></span><span class="o"><span class="o">::</span></span></span><span class="n"><span class="n">value_type</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">>&amp;</span></span> <span class="n"><span class="n">x</span></span><span class="p"><span class="p">);</span></span>
</code></pre>
    <p><em>Returns:</em> An array of data-parallel objects with the <code class="highlight"><span class="n">i</span></code>-th <code class="highlight"><span class="n">simd</span></code>/<code class="highlight"><span class="n">simd_mask</span></code> element of the <code class="highlight"><span class="n">j</span></code>-th
element initialized to the value of the element in <code class="highlight"><span class="n">x</span></code> with index <code class="highlight"><span class="n">i</span> <span class="o">+</span> <span class="n">j</span> <span class="o">*</span> <span class="n">V</span><span class="o">::</span><span class="n">size</span><span class="p">()</span></code>.</p>
    <p><em>Remarks:</em> These functions shall not participate in overload resolution unless <span class="ins">either:</span></p>
    <ul>
     <li data-md="">
      <p><span class="del"><code class="highlight"><span class="n">simd_size_v</span><span class="o">&lt;</span><span class="k">typename</span> <span class="n">V</span><span class="o">::</span><span class="n">value_type</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is an integral multiple of <code class="highlight"><span class="n">V</span><span class="o">::</span><span class="n">size</span><span class="p">()</span></code>, and</span></p>
     <li data-md="">
      <p><span class="del">for the overload with a <code class="highlight"><span class="n">simd</span></code> parameter <code class="highlight"><span class="n">is_simd_v</span><span class="o">&lt;</span><span class="n">V</span><span class="o">></span></code> is <code class="highlight">true</code>, for the overload with a <code class="highlight"><span class="n">simd_mask</span></code> parameter <code class="highlight"><span class="n">is_simd_mask_v</span><span class="o">&lt;</span><span class="n">V</span><span class="o">></span></code> is <code class="highlight">true</code>.</span></p>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">is_simd_v</span><span class="o">&lt;</span><span class="n">V</span><span class="o">></span></code> is <code class="highlight">true</code> and <code class="highlight"><span class="n">simd_size_v</span><span class="o">&lt;</span><span class="k">typename</span> <span class="n">V</span><span class="o">::</span><span class="n">value_type</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is an integral multiple of <code class="highlight"><span class="n">V</span><span class="o">::</span><span class="n">size</span><span class="p">()</span></code>, or</span></p>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">is_simd_mask_v</span><span class="o">&lt;</span><span class="n">V</span><span class="o">></span></code> is <code class="highlight">true</code> and <code class="highlight"><span class="n">simd_size_v</span><span class="o">&lt;</span><span class="k">typename</span> <span class="n">V</span><span class="o">::</span><span class="n">simd_type</span><span class="o">::</span><span class="n">value_type</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is an integral multiple of <code class="highlight"><span class="n">V</span><span class="o">::</span><span class="n">size</span><span class="p">()</span></code>.</span></p>
    </ul>
   </blockquote>
   <h2 class="heading settled" data-level="11" id="ch21"><span class="secno">11. </span><span class="content">CH 21</span><a class="self-link" href="#ch21"></a></h2>
   <p>Modify the synopsis for namespace <code class="highlight"><span class="n">simd_abi</span></code> in [<strong>parallel.simd.abi</strong>] as follows:</p>
   <blockquote>
<pre class="highlight"><code class="highlight"><span class="k"><span class="k">namespace</span></span> <span class="n"><span class="n">simd_abi</span></span> <span class="p"><span class="p">{</span></span>
  <span class="k"><span class="k">struct</span></span> <span class="n"><span class="n">scalar</span></span> <span class="p"><span class="p">{};</span></span>
  <span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="kt"><span class="kt">int</span></span> <span class="n"><span class="n">N</span></span><span class="o"><span class="o">></span></span> <span class="k"><span class="k">struct</span></span> <span class="n"><span class="n">fixed_size</span></span> <span class="p"><span class="p">{};</span></span>
  <span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">T</span></span><span class="o"><span class="o">></span></span> <span class="kr"><span class="kr">inline</span></span> <span class="k"><span class="k">constexpr</span></span> <span class="kt"><span class="kt">in</span></span><span class="ins"><span class="kt"><span class="kt">t</span></span></span> <span class="n"><span class="n">max_fixed_size</span></span> <span class="o"><span class="o">=</span></span> <i><span class="n"><span class="n">implementation</span></span><span class="o"><span class="o">-</span></span><span class="n"><span class="n">defined</span></span></i><span class="p"><span class="p">;</span></span>
  <span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">T</span></span><span class="o"><span class="o">></span></span> <span class="k"><span class="k">using</span></span> <span class="n"><span class="n">compatible</span></span> <span class="o"><span class="o">=</span></span> <i><span class="n"><span class="n">implementation</span></span><span class="o"><span class="o">-</span></span><span class="n"><span class="n">defined</span></span></i><span class="p"><span class="p">;</span></span>
  <span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">T</span></span><span class="o"><span class="o">></span></span> <span class="k"><span class="k">using</span></span> <span class="n"><span class="n">native</span></span> <span class="o"><span class="o">=</span></span> <i><span class="n"><span class="n">implementation</span></span><span class="o"><span class="o">-</span></span><span class="n"><span class="n">defined</span></span></i><span class="p"><span class="p">;</span></span>
<span class="p"><span class="p">}</span></span>
</code></pre>
   </blockquote>
   <h2 class="heading settled" data-level="12" id="ch23"><span class="secno">12. </span><span class="content">CH 23</span><a class="self-link" href="#ch23"></a></h2>
   <p>Modify [<strong>parallel.simd.abi</strong>] paragraph 9 as follows:</p>
   <blockquote>
     <code class="highlight"><span class="n">compatible</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> is an implementation-defined alias for an ABI tag.
[ <em>Note:</em> The intent is to use the ABI tag producing the most efficient data-parallel execution for the element type <code class="highlight"><span class="n">T</span></code> that ensures ABI compatibility between translation units on the target architecture.
— <em>end note</em> ] 
    <p>[ <em>Example:</em> Consider a target architecture supporting the extended ABI tags <code class="highlight"><span class="n">__simd128</span></code> and <code class="highlight"><span class="n">__simd256</span></code>, where the <code class="highlight"><span class="n">__simd256</span></code> type requires an optional ISA extension on said architecture. Also,
the target architecture does not support long double with either ABI tag. The implementation therefore defines <span class="ins"><code class="highlight"><span class="n">compatible</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> as an alias for:</span></p>
    <ul>
     <li data-md="">
      <p><span class="del"><code class="highlight"><span class="n">compatible</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> is an alias for __simd128 for all vectorizable T, except <code class="highlight"><span class="kt">long</span> <span class="kt">double</span></code>, and</span></p>
     <li data-md="">
      <p><span class="del"><code class="highlight"><span class="n">compatible</span><span class="o">&lt;</span><span class="kt">long</span> <span class="kt">double</span><span class="o">></span></code> as an alias for scalar.</span></p>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">scalar</span></code> if <code class="highlight"><span class="n">T</span></code> is the same type as <code class="highlight"><span class="kt">long</span> <span class="kt">double</span></code>, and</span></p>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">__simd128</span></code> otherwise.</span> — <em>end example</em> ]</p>
    </ul>
   </blockquote>
   <h2 class="heading settled" data-level="13" id="us42-43"><span class="secno">13. </span><span class="content">US 42, US 43</span><a class="self-link" href="#us42-43"></a></h2>
   <p>Modify [<strong>parallel.simd.binary</strong>] as follows:</p>
   <blockquote>
<pre class="highlight"><span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">+</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">-</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">*</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">/</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">%</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">&amp;</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">|</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">^</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">&lt;&lt;</span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span> <span class="k">operator</span><span class="o">>></span><span class="p">(</span><span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">);</span>
</pre>
    <p><em>Returns:</em> A <code class="highlight"><span class="n">simd</span></code> object initialized with the results of <span class="del">the element-wise application of the indicated operator.</span><span class="ins">applying the indicated operator to <code class="highlight"><span class="n">lhs</span></code> and <code class="highlight"><span class="n">rhs</span></code> as a binary element-wise operation.</span></p>
    <p><em>Throws:</em> Nothing.</p>
    <p><em>Remarks:</em> Each of these operators shall not participate in overload resolution unless the
indicated operator can be applied to objects of type <code class="highlight"><span class="n">value_type</span></code>.</p>
   </blockquote>
   <p>Modify [<strong>parallel.simd.cassign</strong>] as follows:</p>
   <blockquote>
<pre class="highlight"><code class="highlight"><span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">+=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">-=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">*=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">/=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">%=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">&amp;=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">|=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">^=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">&lt;&lt;=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">>>=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">rhs</span></span><span class="p"><span class="p">);</span></span>
<span class="del"><span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">&lt;&lt;=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="kt"><span class="kt">int</span></span> <span class="n"><span class="n">n</span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">>>=</span></span><span class="p"><span class="p">(</span></span><span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="n"><span class="n">lhs</span></span><span class="p"><span class="p">,</span></span> <span class="kt"><span class="kt">int</span></span> <span class="n"><span class="n">n</span></span><span class="p"><span class="p">);</span></span></span>
</code></pre>
    <p><em>Effects:</em> These operators <span class="del">perform the indicated binary element-wise operation.</span><span class="ins">apply the indicated operator to <code class="highlight"><span class="n">lhs</span></code> and <code class="highlight"><span class="n">rhs</span></code> as an element-wise operation.</span></p>
    <p><em>Returns:</em> <code class="highlight"><span class="n">lhs</span></code>.</p>
    <p><em>Throws:</em> Nothing.</p>
    <p><em>Remarks:</em> These operators shall not participate in overload resolution unless the indicated operator can be applied to objects of type <code class="highlight"><span class="n">value_type</span></code>.</p>
    <ins>
     <div>
<pre class="highlight"><span class="k">friend</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="k">operator</span><span class="o">&lt;&lt;=</span><span class="p">(</span><span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="kt">int</span> <span class="n">n</span><span class="p">);</span>
<span class="k">friend</span> <span class="n">simd</span><span class="o">&amp;</span> <span class="k">operator</span><span class="o">>>=</span><span class="p">(</span><span class="n">simd</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="kt">int</span> <span class="n">n</span><span class="p">);</span>
</pre>
      <p><em>Effects:</em> Equivalent to: <code class="highlight"><span class="k">return</span> <span class="k">operator</span>@<span class="o">=</span><span class="p">(</span><span class="n">lhs</span><span class="p">,</span> <span class="n">simd</span><span class="p">(</span><span class="n">n</span><span class="p">));</span></code></p>
      <p><em>Remarks:</em> These operators shall not participate in overload resolution unless the indicated operator can be applied to objects of type <code class="highlight"><span class="n">value_type</span></code>.</p>
     </div>
    </ins>
   </blockquote>
   <p>Modify [<strong>parallel.simd.comparison</strong>] as follows:</p>
   <blockquote>
     <code class="highlight"><pre class="highlight"><span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">mask_type</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">==</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">mask_type</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">!=</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">mask_type</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">>=</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">mask_type</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">&lt;=</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">mask_type</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">></span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">);</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">mask_type</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">&lt;</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">);</span></span>
</pre></code> 
    <p><em>Returns:</em> A <code class="highlight"><span class="n">simd_mask</span></code> object initialized with the results of <span class="del">the element-wise application of the indicated operator.</span><span class="ins">applying the indicated operator to <code class="highlight"><span class="n">lhs</span></code> and <code class="highlight"><span class="n">rhs</span></code> as a binary element-wise operation.</span></p>
    <p><em>Throws:</em> Nothing.</p>
   </blockquote>
   <p>Modify [<strong>parallel.simd.mask.binary</strong>] as follows:</p>
   <blockquote>
     <code class="highlight"><pre class="highlight"><span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd_mask</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">&amp;&amp;</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">)</span></span> <span class="k"><span class="k">noexcept</span></span><span class="p"><span class="p">;</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd_mask</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">||</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">)</span></span> <span class="k"><span class="k">noexcept</span></span><span class="p"><span class="p">;</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd_mask</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">&amp;</span></span> <span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">)</span></span> <span class="k"><span class="k">noexcept</span></span><span class="p"><span class="p">;</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd_mask</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">|</span></span> <span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">)</span></span> <span class="k"><span class="k">noexcept</span></span><span class="p"><span class="p">;</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd_mask</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">^</span></span> <span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">)</span></span> <span class="k"><span class="k">noexcept</span></span><span class="p"><span class="p">;</span></span>
</pre></code> 
    <p><em>Returns:</em> A <code class="highlight"><span class="n">simd_mask</span></code> object initialized with the results of <span class="del">the element-wise appliation of the indicated operator.</span><span class="ins">applying the indicated operator to <code class="highlight"><span class="n">lhs</span></code> and <code class="highlight"><span class="n">rhs</span></code> as a binary element-wise operation.</span></p>
   </blockquote>
   <p>Modify [<strong>parallel.simd.mask.cassign</strong>] as follows:</p>
   <blockquote>
<pre class="highlight"><span class="k">friend</span> <span class="n">simd_mask</span><span class="o">&amp;</span> <span class="k">operator</span><span class="o">&amp;=</span><span class="p">(</span><span class="n">simd_mask</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd_mask</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span>
<span class="k">friend</span> <span class="n">simd_mask</span><span class="o">&amp;</span> <span class="k">operator</span><span class="o">|=</span><span class="p">(</span><span class="n">simd_mask</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd_mask</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span>
<span class="k">friend</span> <span class="n">simd_mask</span><span class="o">&amp;</span> <span class="k">operator</span><span class="o">^=</span><span class="p">(</span><span class="n">simd_mask</span><span class="o">&amp;</span> <span class="n">lhs</span><span class="p">,</span> <span class="k">const</span> <span class="n">simd_mask</span><span class="o">&amp;</span> <span class="n">rhs</span><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span>
</pre>
    <p><em>Effects:</em> These operators <span class="del">perform the indicated binary element-wise operation.</span><span class="ins">apply the indicated operator to <code class="highlight"><span class="n">lhs</span></code> and <code class="highlight"><span class="n">rhs</span></code> as a binary element-wise operation.</span></p>
    <p><em>Returns:</em> <code class="highlight"><span class="n">lhs</span></code>.</p>
   </blockquote>
   <p>Modify [<strong>parallel.simd.mask.comparison</strong>] as follows:</p>
   <blockquote>
     <code class="highlight"><pre class="highlight"><span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd_mask</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">==</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">)</span></span> <span class="k"><span class="k">noexcept</span></span><span class="p"><span class="p">;</span></span>
<span class="k"><span class="k">friend</span></span> <span class="n"><span class="n">simd_mask</span></span> <span class="k"><span class="k">operator</span></span><span class="o"><span class="o">!=</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">lhs</span></span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&amp;</span></span> <span class="ins"><span class="n"><span class="n">rhs</span></span></span><span class="p"><span class="p">)</span></span> <span class="k"><span class="k">noexcept</span></span><span class="p"><span class="p">;</span></span>
</pre></code> 
    <p><em>Returns:</em> An object initialized with the results of <span class="del">the element-wise application of the indicated operator.</span><span class="ins">applying the indicated operator to <code class="highlight"><span class="n">lhs</span></code> and <code class="highlight"><span class="n">rhs</span></code> as a binary element-wise operation.</span></p>
   </blockquote>
   <h2 class="heading settled" data-level="14" id="ch30ch33"><span class="secno">14. </span><span class="content">CH 30, CH 33</span><a class="self-link" href="#ch30ch33"></a></h2>
   <p>Add <code class="highlight"><span class="k">noexcept</span></code> to the following functions in [<strong>parallel.simd</strong>]:</p>
   <ul>
    <li data-md="">
     <p><code class="highlight"><span class="n">simd_cast</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">static_simd_cast</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">split</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">concat</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">reduce</span><span class="p">(</span><span class="k">const</span> <span class="n">const_where_expression</span><span class="o">&lt;</span><span class="n">M</span><span class="p">,</span> <span class="n">V</span><span class="o">>&amp;</span> <span class="n">x</span><span class="p">,</span> <span class="n">plus</span><span class="o">&lt;></span> <span class="n">binary_op</span><span class="p">)</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">reduce</span><span class="p">(</span><span class="k">const</span> <span class="n">const_where_expression</span><span class="o">&lt;</span><span class="n">M</span><span class="p">,</span> <span class="n">V</span><span class="o">>&amp;</span> <span class="n">x</span><span class="p">,</span> <span class="n">multiplies</span><span class="o">&lt;></span> <span class="n">binary_op</span><span class="p">)</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">reduce</span><span class="p">(</span><span class="k">const</span> <span class="n">const_where_expression</span><span class="o">&lt;</span><span class="n">M</span><span class="p">,</span> <span class="n">V</span><span class="o">>&amp;</span> <span class="n">x</span><span class="p">,</span> <span class="n">bit_and</span><span class="o">&lt;></span> <span class="n">binary_op</span><span class="p">)</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">reduce</span><span class="p">(</span><span class="k">const</span> <span class="n">const_where_expression</span><span class="o">&lt;</span><span class="n">M</span><span class="p">,</span> <span class="n">V</span><span class="o">>&amp;</span> <span class="n">x</span><span class="p">,</span> <span class="n">bit_or</span><span class="o">&lt;></span> <span class="n">binary_op</span><span class="p">)</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">reduce</span><span class="p">(</span><span class="k">const</span> <span class="n">const_where_expression</span><span class="o">&lt;</span><span class="n">M</span><span class="p">,</span> <span class="n">V</span><span class="o">>&amp;</span> <span class="n">x</span><span class="p">,</span> <span class="n">bit_xor</span><span class="o">&lt;></span> <span class="n">binary_op</span><span class="p">)</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">hmin</span></code></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">hmax</span></code></p>
    <li data-md="">
     <p>All members of <code class="highlight"><span class="n">const_where_expression</span></code> and <code class="highlight"><span class="n">where_expression</span></code></p>
    <li data-md="">
     <p>All <code class="highlight"><span class="n">simd</span></code> constructors, except <code class="highlight"><span class="n">simd</span><span class="p">(</span><span class="k">const</span> <span class="n">U</span><span class="o">*</span> <span class="n">mem</span><span class="p">,</span> <span class="n">Flags</span> <span class="n">f</span><span class="p">)</span></code></p>
    <li data-md="">
     <p>All <code class="highlight"><span class="n">simd</span></code> member and non-member operators, except <code class="highlight"><span class="k">operator</span><span class="p">[]</span></code></p>
    <li data-md="">
     <p>All <code class="highlight"><span class="n">reference</span></code> member functions</p>
    <li data-md="">
     <p><code class="highlight"><span class="n">simd_mask</span><span class="p">()</span></code></p>
   </ul>
   <p>Remove <code class="highlight"><span class="k">noexcept</span></code> from  the following functions in [<strong>parallel.simd</strong>]:</p>
   <ul>
    <li data-md="">
     <p><code class="highlight"><span class="n">find_first_set</span></code> (only the non-simd overload)</p>
    <p></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">find_last_set</span></code> (only the non-simd overload)</p>
    <p></p>
    <li data-md="">
     <p><code class="highlight"><span class="n">clamp</span></code> (only in the synopsis)</p>
    <p></p>
   </ul>
   <p>Remove the following <em>Throws:</em> paragraphs:</p>
   <ul>
    <li data-md="">
     <p>[<strong>parallel.simd.whereexpr</strong>] paragraph 10</p>
    <li data-md="">
     <p>[<strong>parallel.simd.ctor</strong>] paragraph 3</p>
    <li data-md="">
     <p>[<strong>parallel.simd.unary</strong>] paragraph 5, paragraph 9, paragraph 13, paragraph 17, paragraph 20, paragraph 23, paragraph 27, and paragraph 30</p>
    <li data-md="">
     <p>[<strong>parallel.simd.binary</strong>] paragraph 3 and paragraph 7</p>
    <li data-md="">
     <p>[<strong>parallel.simd.cassign</strong>] paragraph 4</p>
    <li data-md="">
     <p>[<strong>parallel.simd.comparison</strong>] paragraph 3</p>
    <li data-md="">
     <p>[<strong>parallel.simd.reductions</strong>] paragraph 12, paragraph 15, paragraph 19, paragraph 23, paragraph 26, paragraph 29,  paragraph 32,  paragraph 35</p>
    <li data-md="">
     <p>[<strong>parallel.simd.casts</strong>] paragraph 4 and paragraph 10</p>
   </ul>
   <p>Modify [<strong>parallel.simd.overview</strong>] paragraph 2 as follows:</p>
   <blockquote>
     Every specialization of <code class="highlight"><span class="n">simd</span></code> shall be a complete type. The specialization <code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is supported if <code class="highlight"><span class="n">T</span></code> is a vectorizable type and 
    <ul>
     <li data-md="">
      <p><code class="highlight"><span class="n">Abi</span></code> is <code class="highlight"><span class="n">simd_abi</span><span class="o">::</span><span class="n">scalar</span></code>, or</p>
     <li data-md="">
      <p><code class="highlight"><span class="n">Abi</span></code> is <code class="highlight"><span class="n">simd_abi</span><span class="o">::</span><span class="n">fixed_size</span><span class="o">&lt;</span><span class="n">N</span><span class="o">></span></code>, with <code class="highlight"><span class="n">N</span></code> <span class="del">is</span> constrained as defined in 9.2.1.</p>
    </ul>
    <p>If <code class="highlight"><span class="n">Abi</span></code> is an extended ABI tag, it is implementation-defined whether <code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is supported.
[ <em>Note:</em> The intent is for implementations to decide on the basis of the currently targeted system. — <em>end note</em> ]</p>
    <p>If <code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is not supported, the specialization shall have a deleted default constructor, deleted destructor, deleted copy constructor, and deleted copy assignment. <span class="ins">Otherwise, the following are <code class="highlight">true</code>:</span></p>
    <ul>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">is_nothrow_move_constructible_v</span><span class="o">&lt;</span><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>></span></code>, and</span></p>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">is_nothrow_move_assignable_v</span><span class="o">&lt;</span><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>></span></code>, and</span></p>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">is_nothrow_default_constructible_v</span><span class="o">&lt;</span><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>></span></code>.</span></p>
    </ul>
   </blockquote>
   <p>Modify [<strong>parallel.simd.mask.overview</strong>] paragraph 2 as follows:</p>
   <blockquote>
     Every specialization of <code class="highlight"><span class="n">simd_mask</span></code> shall be a complete type. The specialization <code class="highlight"><span class="n">simd_mask</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is supported if <code class="highlight"><span class="n">T</span></code> is a vectorizable type and 
    <ul>
     <li> <code class="highlight"><span class="n">Abi</span></code> is <code class="highlight"><span class="n">simd_abi</span><span class="o">::</span><span class="n">scalar</span></code>, or 
     <li> <code class="highlight"><span class="n">Abi</span></code> is <code class="highlight"><span class="n">simd_abi</span><span class="o">::</span><span class="n">fixed_size</span><span class="o">&lt;</span><span class="n">N</span><span class="o">></span></code>, with <code class="highlight"><span class="n">N</span></code> constrained as defined in (9.2.1). 
    </ul>
    <p>If <code class="highlight"><span class="n">Abi</span></code> is an extended ABI tag, it is implementation-defined whether <code class="highlight"><span class="n">simd_mask</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is supported.
[ <em>Note:</em> The intent is for implementations to decide on the basis of the currently targeted system. — <em>end note</em> ]</p>
    <p>If <code class="highlight"><span class="n">simd_mask</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> is not supported, the specialization shall have a deleted default constructor, deleted destructor, deleted copy constructor, and deleted copy assignment. <span class="ins">Otherwise, the following are <code class="highlight">true</code>:</span></p>
    <ul>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">is_nothrow_move_constructible_v</span><span class="o">&lt;</span><span class="n">simd_mask</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>></span></code>, and</span></p>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">is_nothrow_move_assignable_v</span><span class="o">&lt;</span><span class="n">simd_mask</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>></span></code>, and</span></p>
     <li data-md="">
      <p><span class="ins"><code class="highlight"><span class="n">is_nothrow_default_constructible_v</span><span class="o">&lt;</span><span class="n">simd_mask</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>></span></code>.</span></p>
    </ul>
   </blockquote>
   <p>After [<strong>parallel.simd.mask.ctor</strong>] paragraph 8 add a new paragraph:</p>
   <ins>
    <blockquote> <em>Throws:</em> Nothing. </blockquote>
   </ins>
   <p>After [<strong>parallel.simd.mask.copy</strong>] paragraph 3 and paragraph 7 add a new paragraph:</p>
   <ins>
    <blockquote> <em>Throws:</em> Nothing. </blockquote>
   </ins>
   <p>After [<strong>parallel.simd.mask.reductions</strong>] paragraph 13, paragraph 16, and paragraph 22 add a new paragraph:</p>
   <ins>
    <blockquote> <em>Throws:</em> Nothing. </blockquote>
   </ins>
   <h2 class="heading settled" data-level="15" id="ch38"><span class="secno">15. </span><span class="content">CH 38</span><a class="self-link" href="#ch38"></a></h2>
   <p>Modify [<strong>parallel.simd.overview</strong>] as follows:</p>
   <blockquote>
<pre class="highlight"><code class="highlight"><span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">T</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">simd</span></span> <span class="p"><span class="p">{</span></span>
<span class="k"><span class="k">public</span></span><span class="o"><span class="o">:</span></span>
  <span class="k"><span class="k">using</span></span> <span class="n"><span class="n">value_type</span></span> <span class="o"><span class="o">=</span></span> <span class="n"><span class="n">T</span></span><span class="p"><span class="p">;</span></span>
  <span class="k"><span class="k">using</span></span> <span class="n"><span class="n">reference</span></span> <span class="o"><span class="o">=</span></span> <i><span class="n"><span class="n">see</span></span> <span class="n"><span class="n">below</span></span></i><span class="p"><span class="p">;</span></span>
  <span class="k"><span class="k">using</span></span> <span class="n"><span class="n">mask_type</span></span> <span class="o"><span class="o">=</span></span> <span class="n"><span class="n">simd_mask</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">T</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">></span></span><span class="ins"><span class="p"><span class="p">;</span></span></span>
  <span class="k"><span class="k">using</span></span> <span class="n"><span class="n">abi_type</span></span> <span class="o"><span class="o">=</span></span> <span class="n"><span class="n">Abi</span></span><span class="p"><span class="p">;</span></span>
</code></pre>
   </blockquote>
   <h2 class="heading settled" data-level="16" id="us41us45ch46-47"><span class="secno">16. </span><span class="content">US 41, US 45, CH 46, CH 47</span><a class="self-link" href="#us41us45ch46-47"></a></h2>
   <p>Modify the definition of <code class="highlight"><span class="n">simd</span></code>'s <code class="highlight"><span class="n">U</span><span class="o">&amp;&amp;</span></code> constructor in [<strong>parallel.simd.ctor</strong>] as follows:</p>
   <blockquote>
<pre class="highlight"><span class="k">template</span><span class="o">&lt;</span><span class="k">class</span> <span class="nc">U</span><span class="o">></span> <span class="n">simd</span><span class="p">(</span><span class="n">U</span><span class="o">&amp;&amp;</span><span class="p">);</span>
</pre>
    <p><em>Effects:</em> Constructs an object with each element initialized to the value of the argument
after conversion to <code class="highlight"><span class="n">value_type</span></code>.</p>
    <p><em>Throws:</em> Any exception thrown while converting the argument to <code class="highlight"><span class="n">value_type</span></code>.</p>
    <p><em>Remarks:</em> Let <code class="highlight"><span class="n">From</span></code> <span class="ins">denote</span><span class="del">identify</span> the type <code class="highlight"><span class="n">remove_cv_t</span><span class="o">&lt;</span><span class="n">remove_reference_t</span><span class="o">&lt;</span><span class="n">U</span><span class="o">>></span></code>. This constructor shall not participate in overload resolution unless:</p>
    <ul>
     <li data-md="">
      <p><code class="highlight"><span class="n">From</span></code> is a vectorizable type and every possibly value of <code class="highlight"><span class="n">From</span></code> can be represented with <code class="highlight"><span class="n">value_type</span></code>, or</p>
     <li data-md="">
      <p><code class="highlight"><span class="n">From</span></code> is not an arithmetic type and is implicitly convertible to <code class="highlight"><span class="n">value_type</span></code>, or</p>
     <li data-md="">
      <p><code class="highlight"><span class="n">From</span></code> is int, or</p>
     <li data-md="">
      <p>From is <code class="highlight"><span class="kt">unsigned</span> <span class="kt">int</span></code> and <code class="highlight"><span class="n">value_type</span></code> is an unsigned integral type.</p>
    </ul>
   </blockquote>
   <p>Modify the definition of <code class="highlight"><span class="n">simd_cast</span></code> in [<strong>parallel.simd.casts</strong>] as follows:</p>
   <blockquote>
<pre class="highlight"><code class="highlight"><span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">T</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">U</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span> <i><span class="n"><span class="n">see</span></span> <span class="n"><span class="n">below</span></span></i> <span class="n"><span class="n">simd_cast</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">U</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">>&amp;</span></span> <span class="n"><span class="n">x</span></span><span class="p"><span class="p">);</span></span>
</code></pre>
    <p>Let <code class="highlight"><span class="n">To</span></code> <span class="ins">denote</span><span class="del">identify</span> <code class="highlight"><span class="n">T</span><span class="o">::</span><span class="n">value_type</span></code> if <code class="highlight"><span class="n">is_simd_v</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> is <code class="highlight">true</code>, or <code class="highlight"><span class="n">T</span></code> otherwise.</p>
    <p><em>Returns:</em> A <code class="highlight"><span class="n">simd</span></code> object with the <span class="math">i</span><sup>th</sup> element initialized to <code class="highlight"><span class="k">static_cast</span><span class="o">&lt;</span><span class="n">To</span><span class="o">></span><span class="p">(</span><span class="n">x</span><span class="p">[</span><span class="math"><span class="n">i</span></span><span class="p">])</span></code> for all <span class="math">i</span> ∈ <code class="highlight"><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="n">size</span><span class="p">())</span></code>.</p>
    <p><em>Throws:</em> Nothing.</p>
    <p><em>Remarks:</em> The function shall not participate in overload resolution unless</p>
    <ul>
     <li data-md="">
      <p>every possible value of type <code class="highlight"><span class="n">U</span></code> can be represented with type <code class="highlight"><span class="n">To</span></code>, and</p>
     <li data-md="">
      <p>either</p>
      <ul>
       <li data-md="">
        <p><code class="highlight"><span class="n">is_simd_v</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> is <code class="highlight">false</code>, or</p>
       <li data-md="">
        <p><code class="highlight"><span class="n">T</span><span class="o">::</span><span class="n">size</span><span class="p">()</span> <span class="o">==</span> <span class="n">simd</span><span class="o">&lt;</span><span class="n">U</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>::</span><span class="n">size</span><span class="p">()</span></code> is <code class="highlight">true</code>.</p>
      </ul>
    </ul>
    <p>The return type is</p>
    <ul>
     <li data-md="">
      <p><code class="highlight"><span class="n">T</span></code> if <code class="highlight"><span class="n">is_simd_v</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> is <code class="highlight">true</code><span class="del">, otherwise</span><span class="ins">;</span></p>
     <li data-md="">
      <p><span class="ins">otherwise, </span><code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> <span class="del">is</span><span class="ins">if</span> <code class="highlight"><span class="n">U</span></code> is <span class="ins">the same type as</span> <code class="highlight"><span class="n">T</span></code><span class="del">, otherwise</span><span class="ins">;</span></p>
     <li data-md="">
      <p><span class="ins">otherwise, </span><code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">simd_abi</span><span class="o">::</span><span class="n">fixed_size</span><span class="o">&lt;</span><span class="n">simd</span><span class="o">&lt;</span><span class="n">U</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>::</span><span class="n">size</span><span class="p">()</span><span class="o">>></span></code></p>
    </ul>
   </blockquote>
   <p>Modify the definition of <code class="highlight"><span class="n">static_simd_cast</span></code> in [<strong>parallel.simd.casts</strong>] as follows:</p>
   <blockquote>
<pre class="highlight"><code class="highlight"><span class="k"><span class="k">template</span></span><span class="o"><span class="o">&lt;</span></span><span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">T</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">U</span></span><span class="p"><span class="p">,</span></span> <span class="k"><span class="k">class</span></span> <span class="nc"><span class="nc">Abi</span></span><span class="o"><span class="o">></span></span> <i><span class="n"><span class="n">see</span></span> <span class="n"><span class="n">below</span></span></i> <span class="n"><span class="n">static_simd_cast</span></span><span class="p"><span class="p">(</span></span><span class="k"><span class="k">const</span></span> <span class="n"><span class="n">simd</span></span><span class="o"><span class="o">&lt;</span></span><span class="n"><span class="n">U</span></span><span class="p"><span class="p">,</span></span> <span class="n"><span class="n">Abi</span></span><span class="o"><span class="o">>&amp;</span></span> <span class="n"><span class="n">x</span></span><span class="p"><span class="p">);</span></span>
</code></pre>
    <p>Let <code class="highlight"><span class="n">To</span></code> <span class="ins">denote</span><span class="del">identify</span> <code class="highlight"><span class="n">T</span><span class="o">::</span><span class="n">value_type</span></code> if <code class="highlight"><span class="n">is_simd_v</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> is true or <code class="highlight"><span class="n">T</span></code> otherwise.</p>
    <p><em>Returns:</em> A <code class="highlight"><span class="n">simd</span></code> object with the <span class="math">i</span><sup>th</sup> element initialized to <code class="highlight"><span class="k">static_cast</span><span class="o">&lt;</span><span class="n">To</span><span class="o">></span><span class="p">(</span><span class="n">x</span><span class="p">[</span><span class="math"><span class="n">i</span></span><span class="p">])</span></code> for all <span class="math">i</span> ∈ <code class="highlight"><span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="n">size</span><span class="p">())</span></code>.</p>
    <p><em>Throws:</em> Nothing.</p>
    <p><em>Remarks:</em> The function shall not participate in overload resolution unless either<span class="ins">:</span></p>
    <ul>
     <li data-md="">
      <p><code class="highlight"><span class="n">is_simd_v</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> is <code class="highlight">false</code>, or</p>
     <li data-md="">
      <p><code class="highlight"><span class="n">T</span><span class="o">::</span><span class="n">size</span><span class="p">()</span> <span class="o">==</span> <span class="n">simd</span><span class="o">&lt;</span><span class="n">U</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>::</span><span class="n">size</span><span class="p">()</span></code> is <code class="highlight">true</code>.</p>
    </ul>
    <p>The return type is<span class="ins">:</span></p>
    <ul>
     <li data-md="">
      <p><code class="highlight"><span class="n">T</span></code> if <code class="highlight"><span class="n">is_simd_v</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code> is <code class="highlight">true</code><span class="del">, otherwise</span><span class="ins">;</span></p>
     <li data-md="">
      <p><span class="ins">otherwise, </span><code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">Abi</span><span class="o">></span></code> if either <code class="highlight"><span class="n">U</span></code> is<span class="ins"> the same type as</span> <code class="highlight"><span class="n">T</span></code> or <span class="del"><code class="highlight"><span class="n">U</span></code> and <code class="highlight"><span class="n">T</span></code> are integral types that only differ in signedness, otherwise</span><span class="ins"><code class="highlight"><span class="n">make_signed_t</span><span class="o">&lt;</span><span class="n">U</span><span class="o">></span></code> is the same type as <code class="highlight"><span class="n">make_signed_t</span><span class="o">&lt;</span><span class="n">T</span><span class="o">></span></code>;</span></p>
     <li data-md="">
      <p><span class="ins">otherwise, </span><code class="highlight"><span class="n">simd</span><span class="o">&lt;</span><span class="n">T</span><span class="p">,</span> <span class="n">simd_abi</span><span class="o">::</span><span class="n">fixed_size</span><span class="o">&lt;</span><span class="n">simd</span><span class="o">&lt;</span><span class="n">U</span><span class="p">,</span> <span class="n">Abi</span><span class="o">>::</span><span class="n">size</span><span class="p">()</span><span class="o">>></span></code>.</p>
    </ul>
   </blockquote>
   <h2 class="heading settled" data-level="17" id="us50"><span class="secno">17. </span><span class="content">US 50</span><a class="self-link" href="#us50"></a></h2>
   <p>Modify [<strong>parallel.simd.math</strong>] paragraph 2 as follows:</p>
   <blockquote> Each function overload produced by the above rules applies the indicated <code class="highlight"><span class="o">&lt;</span><span class="n">cmath</span><span class="o">></span></code> function element-wise. <span class="del">The results per element are not required to be bitwise</span><span class="ins">For the mathematical functions, the results per element only need to be approximately</span> equal to the application of the function which is overloaded for the element type. </blockquote>
   <h2 class="heading settled" data-level="18" id="us51"><span class="secno">18. </span><span class="content">US 51</span><a class="self-link" href="#us51"></a></h2>
   <p>Modify [<strong>parallel.simd.synopsis</strong>] as follows:</p>
   <blockquote> <code class="highlight"><span class="kt">bool</span> <span class="nf">all_of</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">bool</span> <span class="nf">any_of</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">bool</span> <span class="nf">none_of</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">bool</span> <span class="nf">some_of</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">int</span> <span class="nf">popcount</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">int</span> <span class="nf">find_first_set</span><span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">int</span> <span class="nf">find_last_set</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> </blockquote>
   <p>Modify [<strong>parallel.simd.mask.reductions</strong>] as follows:</p>
   <blockquote>
     <code class="highlight"><span class="kt">bool</span> <span class="nf">all_of</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">bool</span> <span class="nf">any_of</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">bool</span> <span class="nf">none_of</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">bool</span> <span class="nf">some_of</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">int</span> <span class="nf">popcount</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> 
    <p><em>Returns:</em> <code class="highlight"><span class="n">all_of</span></code> and <code class="highlight"><span class="n">any_of</span></code> return their arguments; <code class="highlight"><span class="n">none_of</span></code> returns the negation of its argument; <code class="highlight"><span class="n">some_of</span></code> returns <code class="highlight">false</code>; <code class="highlight"><span class="n">popcount</span></code> returns the integral representation of its argument.</p>
    <p><em>Remarks:</em> <span class="del">The functions shall not participate in overload resolution unless the argument is of type <code class="highlight"><span class="kt">bool</span></code>.</span><span class="ins">The parameter type <code class="highlight"><em><span class="n">T</span></em></code> is an unspecified type that is only constructible via implicit conversion from <code class="highlight"><span class="kt">bool</span></code>.</span></p>
    <p><code class="highlight"><span class="kt">int</span> <span class="nf">find_first_set</span><span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br> <code class="highlight"><span class="kt">int</span> <span class="nf">find_last_set</span> <span class="p">(</span><em><span class="del"><span class="n">see</span> <span class="n">below</span></span><span class="ins"><span class="n">T</span></span></em><span class="p">)</span> <span class="k">noexcept</span><span class="p">;</span></code><br></p>
    <p><em>Requires:</em> The value of the argument is <code class="highlight">true</code>.</p>
    <p><em>Returns:</em> <code class="highlight"><span class="mi">0</span></code>.</p>
    <p><em>Remarks:</em> <span class="del">The functions shall not participate in overload resolution unless the argument is of type <code class="highlight"><span class="kt">bool</span></code>.</span><span class="ins">The parameter type <code class="highlight"><em><span class="n">T</span></em></code> is an unspecified type that is only constructible via implicit conversion from <code class="highlight"><span class="kt">bool</span></code>.</span></p>
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  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="informative"><span class="content">Informative References</span><a class="self-link" href="#informative"></a></h3>
  <dl>
   <dt id="biblio-n4744">[N4744]
   <dd>ISO/IEC JTC1/SC22/WG21. <a href="https://wg21.link/N4744">Programming Languages — Technical Specification for C++ Extensions for Parallelism Version 2</a>. Proposed Draft Technical Specification. URL: <a href="https://wg21.link/N4744">https://wg21.link/N4744</a>
  </dl>