[question] crossgen2 generates misaligned relocations #96066

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[question] crossgen2 generates misaligned relocations#96066
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@t-mustafin
t-mustafin
opened on Dec 15, 2023

Crossgen2 constructs some code by ObjectDataBuilder class. In some cases the code includes pieces of data, for example relocation pointers. To proper align the data ObjectDataBuilder has method PadAlignment:
https://github.com/dotnet/runtime/blob/486142a4b87ed6e3134bd1a8726156fb3f55157a/src/coreclr/tools/Common/Compiler/DependencyAnalysis/ObjectDataBuilder.cs#L357C44-L357C44
At the same time the only platform which use PadAlignment method is Win32.

Why crossgen2 uses PadAlignment only for Win32 and generates misaligned data for other platforms?
On platforms there misaligned memory operations is not prohibited they may cause performance degradation in compare with aligned operations. Is there some memory/performance investigations for this misaligned/aligned data generation?

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    , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
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}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

    Skip to content
    [question] crossgen2 generates misaligned relocations #96066
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    [question] crossgen2 generates misaligned relocations#96066
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    @t-mustafin
    t-mustafin
    opened on Dec 15, 2023
    Crossgen2 constructs some code by ObjectDataBuilder class. In some cases the code includes pieces of data, for example relocation pointers. To proper align the data ObjectDataBuilder has method PadAlignment:
    https://github.com/dotnet/runtime/blob/486142a4b87ed6e3134bd1a8726156fb3f55157a/src/coreclr/tools/Common/Compiler/DependencyAnalysis/ObjectDataBuilder.cs#L357C44-L357C44
    
At the same time the only platform which use PadAlignment method is Win32.
    Why crossgen2 uses PadAlignment only for Win32 and generates misaligned data for other platforms?
    
On platforms there misaligned memory operations is not prohibited they may cause performance degradation in compare with aligned operations. Is there some memory/performance investigations for this misaligned/aligned data generation?
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

      Skip to content
      [question] crossgen2 generates misaligned relocations #96066
      Open
      Open
      [question] crossgen2 generates misaligned relocations#96066
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      @t-mustafin
      t-mustafin
      opened on Dec 15, 2023
      Crossgen2 constructs some code by ObjectDataBuilder class. In some cases the code includes pieces of data, for example relocation pointers. To proper align the data ObjectDataBuilder has method PadAlignment:
      https://github.com/dotnet/runtime/blob/486142a4b87ed6e3134bd1a8726156fb3f55157a/src/coreclr/tools/Common/Compiler/DependencyAnalysis/ObjectDataBuilder.cs#L357C44-L357C44
      
At the same time the only platform which use PadAlignment method is Win32.
      Why crossgen2 uses PadAlignment only for Win32 and generates misaligned data for other platforms?
      
On platforms there misaligned memory operations is not prohibited they may cause performance degradation in compare with aligned operations. Is there some memory/performance investigations for this misaligned/aligned data generation?
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
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} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

        Skip to content
        [question] crossgen2 generates misaligned relocations #96066
        Open
        Open
        [question] crossgen2 generates misaligned relocations#96066
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        area-ReadyToRunquestionAnswer questions and provide assistance, not an issue with source code or documentation.
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        @t-mustafin
        t-mustafin
        opened on Dec 15, 2023
        Crossgen2 constructs some code by ObjectDataBuilder class. In some cases the code includes pieces of data, for example relocation pointers. To proper align the data ObjectDataBuilder has method PadAlignment:
        https://github.com/dotnet/runtime/blob/486142a4b87ed6e3134bd1a8726156fb3f55157a/src/coreclr/tools/Common/Compiler/DependencyAnalysis/ObjectDataBuilder.cs#L357C44-L357C44
        
At the same time the only platform which use PadAlignment method is Win32.
        Why crossgen2 uses PadAlignment only for Win32 and generates misaligned data for other platforms?
        
On platforms there misaligned memory operations is not prohibited they may cause performance degradation in compare with aligned operations. Is there some memory/performance investigations for this misaligned/aligned data generation?
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} 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
          [question] crossgen2 generates misaligned relocations #96066
          Open
          Open
          [question] crossgen2 generates misaligned relocations#96066
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          area-ReadyToRunquestionAnswer questions and provide assistance, not an issue with source code or documentation.
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          @t-mustafin
          t-mustafin
          opened on Dec 15, 2023
          Crossgen2 constructs some code by ObjectDataBuilder class. In some cases the code includes pieces of data, for example relocation pointers. To proper align the data ObjectDataBuilder has method PadAlignment:
          https://github.com/dotnet/runtime/blob/486142a4b87ed6e3134bd1a8726156fb3f55157a/src/coreclr/tools/Common/Compiler/DependencyAnalysis/ObjectDataBuilder.cs#L357C44-L357C44
          
At the same time the only platform which use PadAlignment method is Win32.
          Why crossgen2 uses PadAlignment only for Win32 and generates misaligned data for other platforms?
          
On platforms there misaligned memory operations is not prohibited they may cause performance degradation in compare with aligned operations. Is there some memory/performance investigations for this misaligned/aligned data generation?
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

            Skip to content
            [question] crossgen2 generates misaligned relocations #96066
            Open
            Open
            [question] crossgen2 generates misaligned relocations#96066
            Labels
            area-ReadyToRunquestionAnswer questions and provide assistance, not an issue with source code or documentation.
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            Description
            @t-mustafin
            t-mustafin
            opened on Dec 15, 2023
            Crossgen2 constructs some code by ObjectDataBuilder class. In some cases the code includes pieces of data, for example relocation pointers. To proper align the data ObjectDataBuilder has method PadAlignment:
            https://github.com/dotnet/runtime/blob/486142a4b87ed6e3134bd1a8726156fb3f55157a/src/coreclr/tools/Common/Compiler/DependencyAnalysis/ObjectDataBuilder.cs#L357C44-L357C44
            
At the same time the only platform which use PadAlignment method is Win32.
            Why crossgen2 uses PadAlignment only for Win32 and generates misaligned data for other platforms?
            
On platforms there misaligned memory operations is not prohibited they may cause performance degradation in compare with aligned operations. Is there some memory/performance investigations for this misaligned/aligned data generation?
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

              Skip to content
              [question] crossgen2 generates misaligned relocations #96066
              Open
              Open
              [question] crossgen2 generates misaligned relocations#96066
              Labels
              area-ReadyToRunquestionAnswer questions and provide assistance, not an issue with source code or documentation.
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              @t-mustafin
              t-mustafin
              opened on Dec 15, 2023
              Crossgen2 constructs some code by ObjectDataBuilder class. In some cases the code includes pieces of data, for example relocation pointers. To proper align the data ObjectDataBuilder has method PadAlignment:
              https://github.com/dotnet/runtime/blob/486142a4b87ed6e3134bd1a8726156fb3f55157a/src/coreclr/tools/Common/Compiler/DependencyAnalysis/ObjectDataBuilder.cs#L357C44-L357C44
              
At the same time the only platform which use PadAlignment method is Win32.
              Why crossgen2 uses PadAlignment only for Win32 and generates misaligned data for other platforms?
              
On platforms there misaligned memory operations is not prohibited they may cause performance degradation in compare with aligned operations. Is there some memory/performance investigations for this misaligned/aligned data generation?
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

                Skip to content
                [question] crossgen2 generates misaligned relocations #96066
                Open
                Open
                [question] crossgen2 generates misaligned relocations#96066
                Labels
                area-ReadyToRunquestionAnswer questions and provide assistance, not an issue with source code or documentation.
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                @t-mustafin
                t-mustafin
                opened on Dec 15, 2023
                Crossgen2 constructs some code by ObjectDataBuilder class. In some cases the code includes pieces of data, for example relocation pointers. To proper align the data ObjectDataBuilder has method PadAlignment:
                https://github.com/dotnet/runtime/blob/486142a4b87ed6e3134bd1a8726156fb3f55157a/src/coreclr/tools/Common/Compiler/DependencyAnalysis/ObjectDataBuilder.cs#L357C44-L357C44
                
At the same time the only platform which use PadAlignment method is Win32.
                Why crossgen2 uses PadAlignment only for Win32 and generates misaligned data for other platforms?
                
On platforms there misaligned memory operations is not prohibited they may cause performance degradation in compare with aligned operations. Is there some memory/performance investigations for this misaligned/aligned data generation?
                Metadata
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                Assignees
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