Improve String.Substring performance#62577

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nietras wants to merge 8 commits into from
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Improve String.Substring performance #62577

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8 commits
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15d859d
Improve String.Substring performance
nietras Dec 9, 2021
626c675
copy Span.Slice checks for perf
nietras Dec 9, 2021
5550268
address feedback, separate detailed throw
nietras Dec 10, 2021
bdb0ae3
short length copy
nietras Dec 11, 2021
81aa008
revert small copy code
nietras Dec 14, 2021
4fc8108
nit
nietras Dec 14, 2021
7389f9b
paren nit
nietras Dec 14, 2021
15ce699
clean usings
nietras Dec 14, 2021
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67 changes: 51 additions & 16 deletions src/libraries/System.Private.CoreLib/src/System/String.Manipulation.cs
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Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -3,6 +3,7 @@

using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Numerics;
using System.Runtime.InteropServices;
Expand DownExpand Up@@ -1846,43 +1847,77 @@ private static void CheckStringSplitOptions(StringSplitOptions options)

// Returns a substring of this string.
//
public string Substring(int startIndex) => Substring(startIndex, Length - startIndex);

public string Substring(int startIndex, int length)
public string Substring(int startIndex)
{
if (startIndex < 0)
if (startIndex == 0)
{
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
return this;
}

if (startIndex > Length)
int thisLength = Length;
if (startIndex == thisLength)
{
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
return string.Empty;
}

if (length < 0)
{
throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
}
// Copy Span.Slice checks for perf
if ((uint)startIndex > (uint)thisLength)
ThrowSubstringArgumentOutRangeException(startIndex, thisLength - startIndex);

if (startIndex > Length - length)
{
throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
}
return InternalSubString(startIndex, thisLength - startIndex);
}

public string Substring(int startIndex, int length)
{
// Copy Span.Slice checks for perf
int thisLength = Length;
#if TARGET_64BIT
// Since start and length are both 32-bit, their sum can be computed across a 64-bit domain
// without loss of fidelity. The cast to uint before the cast to ulong ensures that the
// extension from 32- to 64-bit is zero-extending rather than sign-extending. The end result
// of this is that if either input is negative or if the input sum overflows past Int32.MaxValue,
// that information is captured correctly in the comparison against the backing _length field.
// We don't use this same mechanism in a 32-bit process due to the overhead of 64-bit arithmetic.
if ((ulong)(uint)startIndex + (ulong)(uint)length > (ulong)(uint)thisLength)
ThrowSubstringArgumentOutRangeException(startIndex, length);
#else
if ((uint)startIndex > (uint)thisLength || (uint)length > (uint)(thisLength - startIndex))
ThrowSubstringArgumentOutRangeException(startIndex, length);
#endif

if (length == 0)
{
return string.Empty;
}

if (startIndex == 0 && length == this.Length)
if (length == thisLength)
{
return this;
}

return InternalSubString(startIndex, length);
}

[DoesNotReturn]
private void ThrowSubstringArgumentOutRangeException(int startIndex, int length)
{
if (startIndex < 0)
{
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
}
if (startIndex > Length)
{
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
}
if (length < 0)
{
throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
}
// Check not needed since we only call this when startIndex, length are out of range
//if (startIndex > Length - length)
throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
}

private string InternalSubString(int startIndex, int length)
{
Debug.Assert(startIndex >= 0 && startIndex <= this.Length, "StartIndex is out of range!");
Expand Down
, 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
 blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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Improve String.Substring performance#62577

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 Closed

nietras
wants to merge
8
commits into

from

 Closed


Improve String.Substring performance
#62577
 Changes from all commits
Commits

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8 commits


Select commit
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15d859d

Improve String.Substring performance


nietras Dec 9, 2021
626c675

copy Span.Slice checks for perf


nietras Dec 9, 2021
5550268

address feedback, separate detailed throw


nietras Dec 10, 2021
bdb0ae3

short length copy


nietras Dec 11, 2021
81aa008

revert small copy code


nietras Dec 14, 2021
4fc8108

nit


nietras Dec 14, 2021
7389f9b

paren nit


nietras Dec 14, 2021
15ce699

clean usings


nietras Dec 14, 2021

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67 changes: 51 additions & 16 deletions
src/libraries/System.Private.CoreLib/src/System/String.Manipulation.cs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -3,6 +3,7 @@

using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Numerics;
using System.Runtime.InteropServices;
Expand DownExpand Up@@ -1846,43 +1847,77 @@ private static void CheckStringSplitOptions(StringSplitOptions options)

 // Returns a substring of this string.
 //
 public string Substring(int startIndex) => Substring(startIndex, Length - startIndex);

 public string Substring(int startIndex, int length)
 public string Substring(int startIndex)
 {
 if (startIndex < 0)
 if (startIndex == 0)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
return this;
 }

 if (startIndex > Length)
 int thisLength = Length;
 if (startIndex == thisLength)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
return string.Empty;
 }

 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Copy Span.Slice checks for perf
 if ((uint)startIndex > (uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, thisLength - startIndex);

 if (startIndex > Length - length)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }
 return InternalSubString(startIndex, thisLength - startIndex);
 }

 public string Substring(int startIndex, int length)
 {
 // Copy Span.Slice checks for perf
 int thisLength = Length;
#if TARGET_64BIT
 // Since start and length are both 32-bit, their sum can be computed across a 64-bit domain
 // without loss of fidelity. The cast to uint before the cast to ulong ensures that the
 // extension from 32- to 64-bit is zero-extending rather than sign-extending. The end result
 // of this is that if either input is negative or if the input sum overflows past Int32.MaxValue,
 // that information is captured correctly in the comparison against the backing _length field.
 // We don't use this same mechanism in a 32-bit process due to the overhead of 64-bit arithmetic.
 if ((ulong)(uint)startIndex + (ulong)(uint)length > (ulong)(uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#else
 if ((uint)startIndex > (uint)thisLength || (uint)length > (uint)(thisLength - startIndex))
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#endif

 if (length == 0)
 {
 return string.Empty;
 }

 if (startIndex == 0 && length == this.Length)
 if (length == thisLength)
 {
 return this;
 }

 return InternalSubString(startIndex, length);
 }

 [DoesNotReturn]
 private void ThrowSubstringArgumentOutRangeException(int startIndex, int length)
 {
 if (startIndex < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
 }
 if (startIndex > Length)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
 }
 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Check not needed since we only call this when startIndex, length are out of range
 //if (startIndex > Length - length)
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }

 private string InternalSubString(int startIndex, int length)
 {
 Debug.Assert(startIndex >= 0 && startIndex <= this.Length, "StartIndex is out of range!");
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Improve String.Substring performance#62577

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to your account

 Closed

nietras
wants to merge
8
commits into

from

 Closed


Improve String.Substring performance
#62577
 Changes from all commits
Commits

Show all changes


8 commits


Select commit
Hold shift + click to select a range
15d859d

Improve String.Substring performance


nietras Dec 9, 2021
626c675

copy Span.Slice checks for perf


nietras Dec 9, 2021
5550268

address feedback, separate detailed throw


nietras Dec 10, 2021
bdb0ae3

short length copy


nietras Dec 11, 2021
81aa008

revert small copy code


nietras Dec 14, 2021
4fc8108

nit


nietras Dec 14, 2021
7389f9b

paren nit


nietras Dec 14, 2021
15ce699

clean usings


nietras Dec 14, 2021

File filter

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67 changes: 51 additions & 16 deletions
src/libraries/System.Private.CoreLib/src/System/String.Manipulation.cs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -3,6 +3,7 @@

using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Numerics;
using System.Runtime.InteropServices;
Expand DownExpand Up@@ -1846,43 +1847,77 @@ private static void CheckStringSplitOptions(StringSplitOptions options)

 // Returns a substring of this string.
 //
 public string Substring(int startIndex) => Substring(startIndex, Length - startIndex);

 public string Substring(int startIndex, int length)
 public string Substring(int startIndex)
 {
 if (startIndex < 0)
 if (startIndex == 0)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
return this;
 }

 if (startIndex > Length)
 int thisLength = Length;
 if (startIndex == thisLength)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
return string.Empty;
 }

 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Copy Span.Slice checks for perf
 if ((uint)startIndex > (uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, thisLength - startIndex);

 if (startIndex > Length - length)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }
 return InternalSubString(startIndex, thisLength - startIndex);
 }

 public string Substring(int startIndex, int length)
 {
 // Copy Span.Slice checks for perf
 int thisLength = Length;
#if TARGET_64BIT
 // Since start and length are both 32-bit, their sum can be computed across a 64-bit domain
 // without loss of fidelity. The cast to uint before the cast to ulong ensures that the
 // extension from 32- to 64-bit is zero-extending rather than sign-extending. The end result
 // of this is that if either input is negative or if the input sum overflows past Int32.MaxValue,
 // that information is captured correctly in the comparison against the backing _length field.
 // We don't use this same mechanism in a 32-bit process due to the overhead of 64-bit arithmetic.
 if ((ulong)(uint)startIndex + (ulong)(uint)length > (ulong)(uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#else
 if ((uint)startIndex > (uint)thisLength || (uint)length > (uint)(thisLength - startIndex))
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#endif

 if (length == 0)
 {
 return string.Empty;
 }

 if (startIndex == 0 && length == this.Length)
 if (length == thisLength)
 {
 return this;
 }

 return InternalSubString(startIndex, length);
 }

 [DoesNotReturn]
 private void ThrowSubstringArgumentOutRangeException(int startIndex, int length)
 {
 if (startIndex < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
 }
 if (startIndex > Length)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
 }
 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Check not needed since we only call this when startIndex, length are out of range
 //if (startIndex > Length - length)
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }

 private string InternalSubString(int startIndex, int length)
 {
 Debug.Assert(startIndex >= 0 && startIndex <= this.Length, "StartIndex is out of range!");
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Improve String.Substring performance#62577

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privacy statement. We’ll occasionally send you account related emails.

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 Closed

nietras
wants to merge
8
commits into

from

 Closed


Improve String.Substring performance
#62577
 Changes from all commits
Commits

Show all changes


8 commits


Select commit
Hold shift + click to select a range
15d859d

Improve String.Substring performance


nietras Dec 9, 2021
626c675

copy Span.Slice checks for perf


nietras Dec 9, 2021
5550268

address feedback, separate detailed throw


nietras Dec 10, 2021
bdb0ae3

short length copy


nietras Dec 11, 2021
81aa008

revert small copy code


nietras Dec 14, 2021
4fc8108

nit


nietras Dec 14, 2021
7389f9b

paren nit


nietras Dec 14, 2021
15ce699

clean usings


nietras Dec 14, 2021

File filter

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Conversations

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67 changes: 51 additions & 16 deletions
src/libraries/System.Private.CoreLib/src/System/String.Manipulation.cs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -3,6 +3,7 @@

using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Numerics;
using System.Runtime.InteropServices;
Expand DownExpand Up@@ -1846,43 +1847,77 @@ private static void CheckStringSplitOptions(StringSplitOptions options)

 // Returns a substring of this string.
 //
 public string Substring(int startIndex) => Substring(startIndex, Length - startIndex);

 public string Substring(int startIndex, int length)
 public string Substring(int startIndex)
 {
 if (startIndex < 0)
 if (startIndex == 0)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
return this;
 }

 if (startIndex > Length)
 int thisLength = Length;
 if (startIndex == thisLength)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
return string.Empty;
 }

 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Copy Span.Slice checks for perf
 if ((uint)startIndex > (uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, thisLength - startIndex);

 if (startIndex > Length - length)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }
 return InternalSubString(startIndex, thisLength - startIndex);
 }

 public string Substring(int startIndex, int length)
 {
 // Copy Span.Slice checks for perf
 int thisLength = Length;
#if TARGET_64BIT
 // Since start and length are both 32-bit, their sum can be computed across a 64-bit domain
 // without loss of fidelity. The cast to uint before the cast to ulong ensures that the
 // extension from 32- to 64-bit is zero-extending rather than sign-extending. The end result
 // of this is that if either input is negative or if the input sum overflows past Int32.MaxValue,
 // that information is captured correctly in the comparison against the backing _length field.
 // We don't use this same mechanism in a 32-bit process due to the overhead of 64-bit arithmetic.
 if ((ulong)(uint)startIndex + (ulong)(uint)length > (ulong)(uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#else
 if ((uint)startIndex > (uint)thisLength || (uint)length > (uint)(thisLength - startIndex))
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#endif

 if (length == 0)
 {
 return string.Empty;
 }

 if (startIndex == 0 && length == this.Length)
 if (length == thisLength)
 {
 return this;
 }

 return InternalSubString(startIndex, length);
 }

 [DoesNotReturn]
 private void ThrowSubstringArgumentOutRangeException(int startIndex, int length)
 {
 if (startIndex < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
 }
 if (startIndex > Length)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
 }
 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Check not needed since we only call this when startIndex, length are out of range
 //if (startIndex > Length - length)
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }

 private string InternalSubString(int startIndex, int length)
 {
 Debug.Assert(startIndex >= 0 && startIndex <= this.Length, "StartIndex is out of range!");
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
Improve String.Substring performance#62577

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Improve String.Substring performance
#62577
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15d859d

Improve String.Substring performance


nietras Dec 9, 2021
626c675

copy Span.Slice checks for perf


nietras Dec 9, 2021
5550268

address feedback, separate detailed throw


nietras Dec 10, 2021
bdb0ae3

short length copy


nietras Dec 11, 2021
81aa008

revert small copy code


nietras Dec 14, 2021
4fc8108

nit


nietras Dec 14, 2021
7389f9b

paren nit


nietras Dec 14, 2021
15ce699

clean usings


nietras Dec 14, 2021

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67 changes: 51 additions & 16 deletions
src/libraries/System.Private.CoreLib/src/System/String.Manipulation.cs

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Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -3,6 +3,7 @@

using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Numerics;
using System.Runtime.InteropServices;
Expand DownExpand Up@@ -1846,43 +1847,77 @@ private static void CheckStringSplitOptions(StringSplitOptions options)

 // Returns a substring of this string.
 //
 public string Substring(int startIndex) => Substring(startIndex, Length - startIndex);

 public string Substring(int startIndex, int length)
 public string Substring(int startIndex)
 {
 if (startIndex < 0)
 if (startIndex == 0)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
return this;
 }

 if (startIndex > Length)
 int thisLength = Length;
 if (startIndex == thisLength)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
return string.Empty;
 }

 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Copy Span.Slice checks for perf
 if ((uint)startIndex > (uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, thisLength - startIndex);

 if (startIndex > Length - length)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }
 return InternalSubString(startIndex, thisLength - startIndex);
 }

 public string Substring(int startIndex, int length)
 {
 // Copy Span.Slice checks for perf
 int thisLength = Length;
#if TARGET_64BIT
 // Since start and length are both 32-bit, their sum can be computed across a 64-bit domain
 // without loss of fidelity. The cast to uint before the cast to ulong ensures that the
 // extension from 32- to 64-bit is zero-extending rather than sign-extending. The end result
 // of this is that if either input is negative or if the input sum overflows past Int32.MaxValue,
 // that information is captured correctly in the comparison against the backing _length field.
 // We don't use this same mechanism in a 32-bit process due to the overhead of 64-bit arithmetic.
 if ((ulong)(uint)startIndex + (ulong)(uint)length > (ulong)(uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#else
 if ((uint)startIndex > (uint)thisLength || (uint)length > (uint)(thisLength - startIndex))
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#endif

 if (length == 0)
 {
 return string.Empty;
 }

 if (startIndex == 0 && length == this.Length)
 if (length == thisLength)
 {
 return this;
 }

 return InternalSubString(startIndex, length);
 }

 [DoesNotReturn]
 private void ThrowSubstringArgumentOutRangeException(int startIndex, int length)
 {
 if (startIndex < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
 }
 if (startIndex > Length)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
 }
 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Check not needed since we only call this when startIndex, length are out of range
 //if (startIndex > Length - length)
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }

 private string InternalSubString(int startIndex, int length)
 {
 Debug.Assert(startIndex >= 0 && startIndex <= this.Length, "StartIndex is out of range!");
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Improve String.Substring performance#62577

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 Closed

nietras
wants to merge
8
commits into

from

 Closed


Improve String.Substring performance
#62577
 Changes from all commits
Commits

Show all changes


8 commits


Select commit
Hold shift + click to select a range
15d859d

Improve String.Substring performance


nietras Dec 9, 2021
626c675

copy Span.Slice checks for perf


nietras Dec 9, 2021
5550268

address feedback, separate detailed throw


nietras Dec 10, 2021
bdb0ae3

short length copy


nietras Dec 11, 2021
81aa008

revert small copy code


nietras Dec 14, 2021
4fc8108

nit


nietras Dec 14, 2021
7389f9b

paren nit


nietras Dec 14, 2021
15ce699

clean usings


nietras Dec 14, 2021

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67 changes: 51 additions & 16 deletions
src/libraries/System.Private.CoreLib/src/System/String.Manipulation.cs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -3,6 +3,7 @@

using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Numerics;
using System.Runtime.InteropServices;
Expand DownExpand Up@@ -1846,43 +1847,77 @@ private static void CheckStringSplitOptions(StringSplitOptions options)

 // Returns a substring of this string.
 //
 public string Substring(int startIndex) => Substring(startIndex, Length - startIndex);

 public string Substring(int startIndex, int length)
 public string Substring(int startIndex)
 {
 if (startIndex < 0)
 if (startIndex == 0)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
return this;
 }

 if (startIndex > Length)
 int thisLength = Length;
 if (startIndex == thisLength)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
return string.Empty;
 }

 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Copy Span.Slice checks for perf
 if ((uint)startIndex > (uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, thisLength - startIndex);

 if (startIndex > Length - length)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }
 return InternalSubString(startIndex, thisLength - startIndex);
 }

 public string Substring(int startIndex, int length)
 {
 // Copy Span.Slice checks for perf
 int thisLength = Length;
#if TARGET_64BIT
 // Since start and length are both 32-bit, their sum can be computed across a 64-bit domain
 // without loss of fidelity. The cast to uint before the cast to ulong ensures that the
 // extension from 32- to 64-bit is zero-extending rather than sign-extending. The end result
 // of this is that if either input is negative or if the input sum overflows past Int32.MaxValue,
 // that information is captured correctly in the comparison against the backing _length field.
 // We don't use this same mechanism in a 32-bit process due to the overhead of 64-bit arithmetic.
 if ((ulong)(uint)startIndex + (ulong)(uint)length > (ulong)(uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#else
 if ((uint)startIndex > (uint)thisLength || (uint)length > (uint)(thisLength - startIndex))
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#endif

 if (length == 0)
 {
 return string.Empty;
 }

 if (startIndex == 0 && length == this.Length)
 if (length == thisLength)
 {
 return this;
 }

 return InternalSubString(startIndex, length);
 }

 [DoesNotReturn]
 private void ThrowSubstringArgumentOutRangeException(int startIndex, int length)
 {
 if (startIndex < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
 }
 if (startIndex > Length)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
 }
 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Check not needed since we only call this when startIndex, length are out of range
 //if (startIndex > Length - length)
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }

 private string InternalSubString(int startIndex, int length)
 {
 Debug.Assert(startIndex >= 0 && startIndex <= this.Length, "StartIndex is out of range!");
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Improve String.Substring performance#62577

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 Closed

nietras
wants to merge
8
commits into

from

 Closed


Improve String.Substring performance
#62577
 Changes from all commits
Commits

Show all changes


8 commits


Select commit
Hold shift + click to select a range
15d859d

Improve String.Substring performance


nietras Dec 9, 2021
626c675

copy Span.Slice checks for perf


nietras Dec 9, 2021
5550268

address feedback, separate detailed throw


nietras Dec 10, 2021
bdb0ae3

short length copy


nietras Dec 11, 2021
81aa008

revert small copy code


nietras Dec 14, 2021
4fc8108

nit


nietras Dec 14, 2021
7389f9b

paren nit


nietras Dec 14, 2021
15ce699

clean usings


nietras Dec 14, 2021

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67 changes: 51 additions & 16 deletions
src/libraries/System.Private.CoreLib/src/System/String.Manipulation.cs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -3,6 +3,7 @@

using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Numerics;
using System.Runtime.InteropServices;
Expand DownExpand Up@@ -1846,43 +1847,77 @@ private static void CheckStringSplitOptions(StringSplitOptions options)

 // Returns a substring of this string.
 //
 public string Substring(int startIndex) => Substring(startIndex, Length - startIndex);

 public string Substring(int startIndex, int length)
 public string Substring(int startIndex)
 {
 if (startIndex < 0)
 if (startIndex == 0)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
return this;
 }

 if (startIndex > Length)
 int thisLength = Length;
 if (startIndex == thisLength)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
return string.Empty;
 }

 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Copy Span.Slice checks for perf
 if ((uint)startIndex > (uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, thisLength - startIndex);

 if (startIndex > Length - length)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }
 return InternalSubString(startIndex, thisLength - startIndex);
 }

 public string Substring(int startIndex, int length)
 {
 // Copy Span.Slice checks for perf
 int thisLength = Length;
#if TARGET_64BIT
 // Since start and length are both 32-bit, their sum can be computed across a 64-bit domain
 // without loss of fidelity. The cast to uint before the cast to ulong ensures that the
 // extension from 32- to 64-bit is zero-extending rather than sign-extending. The end result
 // of this is that if either input is negative or if the input sum overflows past Int32.MaxValue,
 // that information is captured correctly in the comparison against the backing _length field.
 // We don't use this same mechanism in a 32-bit process due to the overhead of 64-bit arithmetic.
 if ((ulong)(uint)startIndex + (ulong)(uint)length > (ulong)(uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#else
 if ((uint)startIndex > (uint)thisLength || (uint)length > (uint)(thisLength - startIndex))
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#endif

 if (length == 0)
 {
 return string.Empty;
 }

 if (startIndex == 0 && length == this.Length)
 if (length == thisLength)
 {
 return this;
 }

 return InternalSubString(startIndex, length);
 }

 [DoesNotReturn]
 private void ThrowSubstringArgumentOutRangeException(int startIndex, int length)
 {
 if (startIndex < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
 }
 if (startIndex > Length)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
 }
 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Check not needed since we only call this when startIndex, length are out of range
 //if (startIndex > Length - length)
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }

 private string InternalSubString(int startIndex, int length)
 {
 Debug.Assert(startIndex >= 0 && startIndex <= this.Length, "StartIndex is out of range!");
Expand Down

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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Improve String.Substring performance#62577

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 Closed

nietras
wants to merge
8
commits into

from

 Closed


Improve String.Substring performance
#62577
 Changes from all commits
Commits

Show all changes


8 commits


Select commit
Hold shift + click to select a range
15d859d

Improve String.Substring performance


nietras Dec 9, 2021
626c675

copy Span.Slice checks for perf


nietras Dec 9, 2021
5550268

address feedback, separate detailed throw


nietras Dec 10, 2021
bdb0ae3

short length copy


nietras Dec 11, 2021
81aa008

revert small copy code


nietras Dec 14, 2021
4fc8108

nit


nietras Dec 14, 2021
7389f9b

paren nit


nietras Dec 14, 2021
15ce699

clean usings


nietras Dec 14, 2021

File filter

Filter by extension
Filter by extension
Conversations

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67 changes: 51 additions & 16 deletions
src/libraries/System.Private.CoreLib/src/System/String.Manipulation.cs

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -3,6 +3,7 @@

using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Numerics;
using System.Runtime.InteropServices;
Expand DownExpand Up@@ -1846,43 +1847,77 @@ private static void CheckStringSplitOptions(StringSplitOptions options)

 // Returns a substring of this string.
 //
 public string Substring(int startIndex) => Substring(startIndex, Length - startIndex);

 public string Substring(int startIndex, int length)
 public string Substring(int startIndex)
 {
 if (startIndex < 0)
 if (startIndex == 0)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
return this;
 }

 if (startIndex > Length)
 int thisLength = Length;
 if (startIndex == thisLength)
 {
throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
return string.Empty;
 }

 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Copy Span.Slice checks for perf
 if ((uint)startIndex > (uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, thisLength - startIndex);

 if (startIndex > Length - length)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }
 return InternalSubString(startIndex, thisLength - startIndex);
 }

 public string Substring(int startIndex, int length)
 {
 // Copy Span.Slice checks for perf
 int thisLength = Length;
#if TARGET_64BIT
 // Since start and length are both 32-bit, their sum can be computed across a 64-bit domain
 // without loss of fidelity. The cast to uint before the cast to ulong ensures that the
 // extension from 32- to 64-bit is zero-extending rather than sign-extending. The end result
 // of this is that if either input is negative or if the input sum overflows past Int32.MaxValue,
 // that information is captured correctly in the comparison against the backing _length field.
 // We don't use this same mechanism in a 32-bit process due to the overhead of 64-bit arithmetic.
 if ((ulong)(uint)startIndex + (ulong)(uint)length > (ulong)(uint)thisLength)
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#else
 if ((uint)startIndex > (uint)thisLength || (uint)length > (uint)(thisLength - startIndex))
 ThrowSubstringArgumentOutRangeException(startIndex, length);
#endif

 if (length == 0)
 {
 return string.Empty;
 }

 if (startIndex == 0 && length == this.Length)
 if (length == thisLength)
 {
 return this;
 }

 return InternalSubString(startIndex, length);
 }

 [DoesNotReturn]
 private void ThrowSubstringArgumentOutRangeException(int startIndex, int length)
 {
 if (startIndex < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndex);
 }
 if (startIndex > Length)
 {
 throw new ArgumentOutOfRangeException(nameof(startIndex), SR.ArgumentOutOfRange_StartIndexLargerThanLength);
 }
 if (length < 0)
 {
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_NegativeLength);
 }
 // Check not needed since we only call this when startIndex, length are out of range
 //if (startIndex > Length - length)
 throw new ArgumentOutOfRangeException(nameof(length), SR.ArgumentOutOfRange_IndexLength);
 }

 private string InternalSubString(int startIndex, int length)
 {
 Debug.Assert(startIndex >= 0 && startIndex <= this.Length, "StartIndex is out of range!");
Expand Down