tor-browser

commit f211bee4de135ca2126ff3d277c19e42b6975376
parent 905ed24b39020575a45bcd2e12ce5a99fe2f1b20
Author: Tooru Fujisawa <arai_a@mac.com>
Date:   Fri, 31 Oct 2025 05:22:08 +0000

Bug 1980154 - Part 3: Add SharedScriptCache::UpdateDiskCache that saves cached stencils into the disk cache. r=nbp

Differential Revision: https://phabricator.services.mozilla.com/D270523

Diffstat:
M
dom/script/SharedScriptCache.cpp
 | 
65
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
M
dom/script/SharedScriptCache.h
 | 
2
++
M
js/loader/LoadedScript.h
 | 
5
+++++

3 files changed, 70 insertions(+), 2 deletions(-)
diff --git a/dom/script/SharedScriptCache.cpp b/dom/script/SharedScriptCache.cpp
@@ -6,8 +6,9 @@
 
 #include "SharedScriptCache.h"
 
-#include "ScriptLoadHandler.h"          // ScriptLoadHandler
-#include "ScriptLoader.h"               // ScriptLoader
+#include "ScriptLoadHandler.h"  // ScriptLoadHandler
+#include "ScriptLoader.h"       // ScriptLoader
+#include "js/experimental/CompileScript.h"  // JS::FrontendContext, JS::NewFrontendContext, JS::DestroyFrontendContext
 #include "mozilla/Maybe.h"              // Maybe, Some, Nothing
 #include "mozilla/dom/ContentParent.h"  // dom::ContentParent
 #include "nsIMemoryReporter.h"  // nsIMemoryReporter, MOZ_DEFINE_MALLOC_SIZE_OF, RegisterWeakMemoryReporter, UnregisterWeakMemoryReporter, MOZ_COLLECT_REPORT, KIND_HEAP, UNITS_BYTES
@@ -165,4 +166,64 @@ void SharedScriptCache::PrepareForLastCC() {
   }
 }
 
+static bool ShouldSave(JS::loader::LoadedScript* aLoadedScript,
+                       ScriptLoader::DiskCacheStrategy aStrategy) {
+  if (!aLoadedScript->HasDiskCacheReference()) {
+    return false;
+  }
+
+  if (!aLoadedScript->HasSRI()) {
+    return false;
+  }
+
+  if (aStrategy.mHasSourceLengthMin) {
+    size_t len = JS::GetScriptSourceLength(aLoadedScript->GetStencil());
+    if (len < aStrategy.mSourceLengthMin) {
+      return false;
+    }
+  }
+
+  if (aStrategy.mHasFetchCountMin) {
+    if (aLoadedScript->mFetchCount < aStrategy.mFetchCountMin) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+void SharedScriptCache::UpdateDiskCache() {
+  auto strategy = ScriptLoader::GetDiskCacheStrategy();
+  if (strategy.mIsDisabled) {
+    return;
+  }
+
+  JS::FrontendContext* fc = nullptr;
+
+  for (auto iter = mComplete.Iter(); !iter.Done(); iter.Next()) {
+    JS::loader::LoadedScript* loadedScript = iter.Data().mResource;
+    if (!ShouldSave(loadedScript, strategy)) {
+      continue;
+    }
+
+    if (!fc) {
+      // Lazily create the context only when there's at least one script
+      // that needs to be saved.
+      fc = JS::NewFrontendContext();
+      if (!fc) {
+        return;
+      }
+    }
+
+    ScriptLoader::EncodeBytecodeAndSave(fc, loadedScript);
+
+    loadedScript->DropDiskCacheReference();
+    loadedScript->DropBytecode();
+  }
+
+  if (fc) {
+    JS::DestroyFrontendContext(fc);
+  }
+}
+
 }  // namespace mozilla::dom
diff --git a/dom/script/SharedScriptCache.h b/dom/script/SharedScriptCache.h
@@ -193,6 +193,8 @@ class SharedScriptCache final
   SharedScriptCache();
   void Init();
 
+  void UpdateDiskCache();
+
   // This has to be static because it's also called for loaders that don't have
   // a sheet cache (loaders that are not owned by a document).
   static void LoadCompleted(SharedScriptCache*, ScriptLoadData&);
diff --git a/js/loader/LoadedScript.h b/js/loader/LoadedScript.h
@@ -252,6 +252,11 @@ class LoadedScript : public nsIMemoryReporter {
     mSRIAndBytecode.clearAndFree();
   }
 
+  bool HasSRI() {
+    MOZ_ASSERT(IsSource() || IsCachedStencil());
+    return !mSRIAndBytecode.empty();
+  }
+
   void DropSRI() {
     MOZ_ASSERT(IsSource() || IsCachedStencil());
     mSRIAndBytecode.clearAndFree();