Change ICorProfilerInfo::SetILFunctionBody to use codeversions #33197

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Change ICorProfilerInfo::SetILFunctionBody to use codeversions#33197
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davmason
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area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions

Description

@davmason
davmason
opened on Mar 5, 2020

#32969 is introducing on stack replacement (OSR) for jitted methods, and this means there is a new sharp edge for profilers to find. Currently we do not prevent (but do have documentation that states you shouldn't) profilers from calling ICorProfilerInfo::SetILFunctionBody after a method has already been jitted. Previous to tiered compilation this would be effectively a no-op, unless rejit was called, since the method was already compiled.

Once tiered compilation was introduced, if a profiler sets the IL after a tier 0 compilation has occurred but before a tier 1 has, then the tier 1 will use different IL and have different behavior than tier 0. While this might be unexpected by the profiler author, it won't cause fatal errors.

With OSR, if a profiler calls SetILFunctionBody after tier 0 the new function will potentially be replaced mid method, and if the IL varies significantly then there is plenty of potential for misbehavior or crashes.

As mentioned in #32969 (comment), we could solve this by using the existing code versioning scheme that we use for rejit and tiered compilation. Some extra care would be necessary to preserve the existing behavior of SetILFunctionBody. We want it to be viewed as the new default IL version, so any code that requests the default version should be redirected to the new version provided to SetILFunctionBody, including RequestRevert.

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    , 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
     blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n 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;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} 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
    Change ICorProfilerInfo::SetILFunctionBody to use codeversions #33197
    Closed
    Closed
    Change ICorProfilerInfo::SetILFunctionBody to use codeversions#33197
    Assignees
    davmason
    Labels
    area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
    Description
    @davmason
    davmason
    opened on Mar 5, 2020
    #32969 is introducing on stack replacement (OSR) for jitted methods, and this means there is a new sharp edge for profilers to find. Currently we do not prevent (but do have documentation that states you shouldn't) profilers from calling ICorProfilerInfo::SetILFunctionBody after a method has already been jitted. Previous to tiered compilation this would be effectively a no-op, unless rejit was called, since the method was already compiled.
    Once tiered compilation was introduced, if a profiler sets the IL after a tier 0 compilation has occurred but before a tier 1 has, then the tier 1 will use different IL and have different behavior than tier 0. While this might be unexpected by the profiler author, it won't cause fatal errors.
    With OSR, if a profiler calls SetILFunctionBody after tier 0 the new function will potentially be replaced mid method, and if the IL varies significantly then there is plenty of potential for misbehavior or crashes.
    As mentioned in #32969 (comment), we could solve this by using the existing code versioning scheme that we use for rejit and tiered compilation. Some extra care would be necessary to preserve the existing behavior of SetILFunctionBody. We want it to be viewed as the new default IL version, so any code that requests the default version should be redirected to the new version provided to SetILFunctionBody, including RequestRevert.
    Metadata
    Metadata
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    area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
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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
      Change ICorProfilerInfo::SetILFunctionBody to use codeversions #33197
      Closed
      Closed
      Change ICorProfilerInfo::SetILFunctionBody to use codeversions#33197
      Assignees
      davmason
      Labels
      area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
      Description
      @davmason
      davmason
      opened on Mar 5, 2020
      #32969 is introducing on stack replacement (OSR) for jitted methods, and this means there is a new sharp edge for profilers to find. Currently we do not prevent (but do have documentation that states you shouldn't) profilers from calling ICorProfilerInfo::SetILFunctionBody after a method has already been jitted. Previous to tiered compilation this would be effectively a no-op, unless rejit was called, since the method was already compiled.
      Once tiered compilation was introduced, if a profiler sets the IL after a tier 0 compilation has occurred but before a tier 1 has, then the tier 1 will use different IL and have different behavior than tier 0. While this might be unexpected by the profiler author, it won't cause fatal errors.
      With OSR, if a profiler calls SetILFunctionBody after tier 0 the new function will potentially be replaced mid method, and if the IL varies significantly then there is plenty of potential for misbehavior or crashes.
      As mentioned in #32969 (comment), we could solve this by using the existing code versioning scheme that we use for rejit and tiered compilation. Some extra care would be necessary to preserve the existing behavior of SetILFunctionBody. We want it to be viewed as the new default IL version, so any code that requests the default version should be redirected to the new version provided to SetILFunctionBody, including RequestRevert.
      Metadata
      Metadata
      Assignees
      Labels
      area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
      Type
      No type
      Projects
      No projects
        Milestone
        No milestone
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        None yet
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        No branches or pull requests
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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");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

        Skip to content
        Change ICorProfilerInfo::SetILFunctionBody to use codeversions #33197
        Closed
        Closed
        Change ICorProfilerInfo::SetILFunctionBody to use codeversions#33197
        Assignees
        davmason
        Labels
        area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
        Description
        @davmason
        davmason
        opened on Mar 5, 2020
        #32969 is introducing on stack replacement (OSR) for jitted methods, and this means there is a new sharp edge for profilers to find. Currently we do not prevent (but do have documentation that states you shouldn't) profilers from calling ICorProfilerInfo::SetILFunctionBody after a method has already been jitted. Previous to tiered compilation this would be effectively a no-op, unless rejit was called, since the method was already compiled.
        Once tiered compilation was introduced, if a profiler sets the IL after a tier 0 compilation has occurred but before a tier 1 has, then the tier 1 will use different IL and have different behavior than tier 0. While this might be unexpected by the profiler author, it won't cause fatal errors.
        With OSR, if a profiler calls SetILFunctionBody after tier 0 the new function will potentially be replaced mid method, and if the IL varies significantly then there is plenty of potential for misbehavior or crashes.
        As mentioned in #32969 (comment), we could solve this by using the existing code versioning scheme that we use for rejit and tiered compilation. Some extra care would be necessary to preserve the existing behavior of SetILFunctionBody. We want it to be viewed as the new default IL version, so any code that requests the default version should be redirected to the new version provided to SetILFunctionBody, including RequestRevert.
        Metadata
        Metadata
        Assignees
        Labels
        area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
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        No type
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        No projects
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          No milestone
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          None yet
          Development
          No branches or pull requests
          Issue actions
          
, '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
          Change ICorProfilerInfo::SetILFunctionBody to use codeversions #33197
          Closed
          Closed
          Change ICorProfilerInfo::SetILFunctionBody to use codeversions#33197
          Assignees
          davmason
          Labels
          area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
          Description
          @davmason
          davmason
          opened on Mar 5, 2020
          #32969 is introducing on stack replacement (OSR) for jitted methods, and this means there is a new sharp edge for profilers to find. Currently we do not prevent (but do have documentation that states you shouldn't) profilers from calling ICorProfilerInfo::SetILFunctionBody after a method has already been jitted. Previous to tiered compilation this would be effectively a no-op, unless rejit was called, since the method was already compiled.
          Once tiered compilation was introduced, if a profiler sets the IL after a tier 0 compilation has occurred but before a tier 1 has, then the tier 1 will use different IL and have different behavior than tier 0. While this might be unexpected by the profiler author, it won't cause fatal errors.
          With OSR, if a profiler calls SetILFunctionBody after tier 0 the new function will potentially be replaced mid method, and if the IL varies significantly then there is plenty of potential for misbehavior or crashes.
          As mentioned in #32969 (comment), we could solve this by using the existing code versioning scheme that we use for rejit and tiered compilation. Some extra care would be necessary to preserve the existing behavior of SetILFunctionBody. We want it to be viewed as the new default IL version, so any code that requests the default version should be redirected to the new version provided to SetILFunctionBody, including RequestRevert.
          Metadata
          Metadata
          Assignees
          Labels
          area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
          Type
          No type
          Projects
          No projects
            Milestone
            No milestone
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            None yet
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            No branches or pull requests
            Issue actions
            
, '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
            Change ICorProfilerInfo::SetILFunctionBody to use codeversions #33197
            Closed
            Closed
            Change ICorProfilerInfo::SetILFunctionBody to use codeversions#33197
            Assignees
            davmason
            Labels
            area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
            Description
            @davmason
            davmason
            opened on Mar 5, 2020
            #32969 is introducing on stack replacement (OSR) for jitted methods, and this means there is a new sharp edge for profilers to find. Currently we do not prevent (but do have documentation that states you shouldn't) profilers from calling ICorProfilerInfo::SetILFunctionBody after a method has already been jitted. Previous to tiered compilation this would be effectively a no-op, unless rejit was called, since the method was already compiled.
            Once tiered compilation was introduced, if a profiler sets the IL after a tier 0 compilation has occurred but before a tier 1 has, then the tier 1 will use different IL and have different behavior than tier 0. While this might be unexpected by the profiler author, it won't cause fatal errors.
            With OSR, if a profiler calls SetILFunctionBody after tier 0 the new function will potentially be replaced mid method, and if the IL varies significantly then there is plenty of potential for misbehavior or crashes.
            As mentioned in #32969 (comment), we could solve this by using the existing code versioning scheme that we use for rejit and tiered compilation. Some extra care would be necessary to preserve the existing behavior of SetILFunctionBody. We want it to be viewed as the new default IL version, so any code that requests the default version should be redirected to the new version provided to SetILFunctionBody, including RequestRevert.
            Metadata
            Metadata
            Assignees
            Labels
            area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
            Type
            No type
            Projects
            No projects
              Milestone
              No milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, '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
              Change ICorProfilerInfo::SetILFunctionBody to use codeversions #33197
              Closed
              Closed
              Change ICorProfilerInfo::SetILFunctionBody to use codeversions#33197
              Assignees
              davmason
              Labels
              area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
              Description
              @davmason
              davmason
              opened on Mar 5, 2020
              #32969 is introducing on stack replacement (OSR) for jitted methods, and this means there is a new sharp edge for profilers to find. Currently we do not prevent (but do have documentation that states you shouldn't) profilers from calling ICorProfilerInfo::SetILFunctionBody after a method has already been jitted. Previous to tiered compilation this would be effectively a no-op, unless rejit was called, since the method was already compiled.
              Once tiered compilation was introduced, if a profiler sets the IL after a tier 0 compilation has occurred but before a tier 1 has, then the tier 1 will use different IL and have different behavior than tier 0. While this might be unexpected by the profiler author, it won't cause fatal errors.
              With OSR, if a profiler calls SetILFunctionBody after tier 0 the new function will potentially be replaced mid method, and if the IL varies significantly then there is plenty of potential for misbehavior or crashes.
              As mentioned in #32969 (comment), we could solve this by using the existing code versioning scheme that we use for rejit and tiered compilation. Some extra care would be necessary to preserve the existing behavior of SetILFunctionBody. We want it to be viewed as the new default IL version, so any code that requests the default version should be redirected to the new version provided to SetILFunctionBody, including RequestRevert.
              Metadata
              Metadata
              Assignees
              Labels
              area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
              Type
              No type
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              No projects
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                No milestone
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                None yet
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                No branches or pull requests
                Issue actions
                
, '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
                Change ICorProfilerInfo::SetILFunctionBody to use codeversions #33197
                Closed
                Closed
                Change ICorProfilerInfo::SetILFunctionBody to use codeversions#33197
                Assignees
                davmason
                Labels
                area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
                Description
                @davmason
                davmason
                opened on Mar 5, 2020
                #32969 is introducing on stack replacement (OSR) for jitted methods, and this means there is a new sharp edge for profilers to find. Currently we do not prevent (but do have documentation that states you shouldn't) profilers from calling ICorProfilerInfo::SetILFunctionBody after a method has already been jitted. Previous to tiered compilation this would be effectively a no-op, unless rejit was called, since the method was already compiled.
                Once tiered compilation was introduced, if a profiler sets the IL after a tier 0 compilation has occurred but before a tier 1 has, then the tier 1 will use different IL and have different behavior than tier 0. While this might be unexpected by the profiler author, it won't cause fatal errors.
                With OSR, if a profiler calls SetILFunctionBody after tier 0 the new function will potentially be replaced mid method, and if the IL varies significantly then there is plenty of potential for misbehavior or crashes.
                As mentioned in #32969 (comment), we could solve this by using the existing code versioning scheme that we use for rejit and tiered compilation. Some extra care would be necessary to preserve the existing behavior of SetILFunctionBody. We want it to be viewed as the new default IL version, so any code that requests the default version should be redirected to the new version provided to SetILFunctionBody, including RequestRevert.
                Metadata
                Metadata
                Assignees
                Labels
                area-Diagnostics-coreclrenhancementProduct code improvement that does NOT require public API changes/additions
                Type
                No type
                Projects
                No projects
                  Milestone
                  No milestone
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                  None yet
                  Development
                  No branches or pull requests
                  Issue actions