Add m-esr52 at 52.6.0

1 files changed, 286 insertions, 0 deletions

diff --git a/layout/style/RuleProcessorCache.cpp b/layout/style/RuleProcessorCache.cpp
new file mode 100644
index 000000000..23832c230
--- /dev/null
+++ b/layout/style/RuleProcessorCache.cpp
@@ -0,0 +1,286 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * cache of re-usable nsCSSRuleProcessors for given sets of style sheets
+ */
+
+#include "RuleProcessorCache.h"
+
+#include <algorithm>
+#include "nsCSSRuleProcessor.h"
+#include "nsThreadUtils.h"
+
+using namespace mozilla;
+
+NS_IMPL_ISUPPORTS(RuleProcessorCache, nsIMemoryReporter)
+
+MOZ_DEFINE_MALLOC_SIZE_OF(RuleProcessorCacheMallocSizeOf)
+
+NS_IMETHODIMP
+RuleProcessorCache::CollectReports(nsIHandleReportCallback* aHandleReport,
+                                   nsISupports* aData, bool aAnonymize)
+{
+  MOZ_COLLECT_REPORT(
+    "explicit/layout/rule-processor-cache", KIND_HEAP, UNITS_BYTES,
+    SizeOfIncludingThis(RuleProcessorCacheMallocSizeOf),
+    "Memory used for cached rule processors.");
+
+  return NS_OK;
+}
+
+RuleProcessorCache::~RuleProcessorCache()
+{
+  UnregisterWeakMemoryReporter(this);
+
+  for (Entry& e : mEntries) {
+    for (DocumentEntry& de : e.mDocumentEntries) {
+      if (de.mRuleProcessor->GetExpirationState()->IsTracked()) {
+        mExpirationTracker.RemoveObject(de.mRuleProcessor);
+      }
+      de.mRuleProcessor->SetInRuleProcessorCache(false);
+    }
+  }
+}
+
+void
+RuleProcessorCache::InitMemoryReporter()
+{
+  RegisterWeakMemoryReporter(this);
+}
+
+/* static */ bool
+RuleProcessorCache::EnsureGlobal()
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (gShutdown) {
+    return false;
+  }
+
+  if (!gRuleProcessorCache) {
+    gRuleProcessorCache = new RuleProcessorCache;
+    gRuleProcessorCache->InitMemoryReporter();
+  }
+  return true;
+}
+
+/* static */ void
+RuleProcessorCache::RemoveSheet(CSSStyleSheet* aSheet)
+{
+  if (!EnsureGlobal()) {
+    return;
+  }
+  gRuleProcessorCache->DoRemoveSheet(aSheet);
+}
+
+#ifdef DEBUG
+/* static */ bool
+RuleProcessorCache::HasRuleProcessor(nsCSSRuleProcessor* aRuleProcessor)
+{
+  if (!EnsureGlobal()) {
+    return false;
+  }
+  return gRuleProcessorCache->DoHasRuleProcessor(aRuleProcessor);
+}
+#endif
+
+/* static */ void
+RuleProcessorCache::RemoveRuleProcessor(nsCSSRuleProcessor* aRuleProcessor)
+{
+  if (!EnsureGlobal()) {
+    return;
+  }
+  gRuleProcessorCache->DoRemoveRuleProcessor(aRuleProcessor);
+}
+
+/* static */ nsCSSRuleProcessor*
+RuleProcessorCache::GetRuleProcessor(const nsTArray<CSSStyleSheet*>& aSheets,
+                                     nsPresContext* aPresContext)
+{
+  if (!EnsureGlobal()) {
+    return nullptr;
+  }
+  return gRuleProcessorCache->DoGetRuleProcessor(aSheets, aPresContext);
+}
+
+/* static */ void
+RuleProcessorCache::PutRuleProcessor(
+    const nsTArray<CSSStyleSheet*>& aSheets,
+    nsTArray<css::DocumentRule*>&& aDocumentRulesInSheets,
+    const nsDocumentRuleResultCacheKey& aCacheKey,
+    nsCSSRuleProcessor* aRuleProcessor)
+{
+  if (!EnsureGlobal()) {
+    return;
+  }
+  gRuleProcessorCache->DoPutRuleProcessor(aSheets, Move(aDocumentRulesInSheets),
+                                          aCacheKey, aRuleProcessor);
+}
+
+/* static */ void
+RuleProcessorCache::StartTracking(nsCSSRuleProcessor* aRuleProcessor)
+{
+  if (!EnsureGlobal()) {
+    return;
+  }
+  return gRuleProcessorCache->DoStartTracking(aRuleProcessor);
+}
+
+/* static */ void
+RuleProcessorCache::StopTracking(nsCSSRuleProcessor* aRuleProcessor)
+{
+  if (!EnsureGlobal()) {
+    return;
+  }
+  return gRuleProcessorCache->DoStopTracking(aRuleProcessor);
+}
+
+void
+RuleProcessorCache::DoRemoveSheet(CSSStyleSheet* aSheet)
+{
+  Entry* last = std::remove_if(mEntries.begin(), mEntries.end(),
+                               HasSheet_ThenRemoveRuleProcessors(this, aSheet));
+  mEntries.TruncateLength(last - mEntries.begin());
+}
+
+nsCSSRuleProcessor*
+RuleProcessorCache::DoGetRuleProcessor(const nsTArray<CSSStyleSheet*>& aSheets,
+                                       nsPresContext* aPresContext)
+{
+  for (Entry& e : mEntries) {
+    if (e.mSheets == aSheets) {
+      for (DocumentEntry& de : e.mDocumentEntries) {
+        if (de.mCacheKey.Matches(aPresContext, e.mDocumentRulesInSheets)) {
+          return de.mRuleProcessor;
+        }
+      }
+      // Entry::mSheets is unique; if we matched aSheets but didn't
+      // find a matching DocumentEntry, we won't find one later in
+      // mEntries.
+      return nullptr;
+    }
+  }
+  return nullptr;
+}
+
+void
+RuleProcessorCache::DoPutRuleProcessor(
+    const nsTArray<CSSStyleSheet*>& aSheets,
+    nsTArray<css::DocumentRule*>&& aDocumentRulesInSheets,
+    const nsDocumentRuleResultCacheKey& aCacheKey,
+    nsCSSRuleProcessor* aRuleProcessor)
+{
+  MOZ_ASSERT(!aRuleProcessor->IsInRuleProcessorCache());
+
+  Entry* entry = nullptr;
+  for (Entry& e : mEntries) {
+    if (e.mSheets == aSheets) {
+      entry = &e;
+      break;
+    }
+  }
+
+  if (!entry) {
+    entry = mEntries.AppendElement();
+    entry->mSheets = aSheets;
+    entry->mDocumentRulesInSheets = aDocumentRulesInSheets;
+    for (CSSStyleSheet* sheet : aSheets) {
+      sheet->SetInRuleProcessorCache();
+    }
+  } else {
+    MOZ_ASSERT(entry->mDocumentRulesInSheets == aDocumentRulesInSheets,
+               "DocumentRule array shouldn't have changed");
+  }
+
+#ifdef DEBUG
+  for (DocumentEntry& de : entry->mDocumentEntries) {
+    MOZ_ASSERT(de.mCacheKey != aCacheKey,
+               "should not have duplicate document cache keys");
+  }
+#endif
+
+  DocumentEntry* documentEntry = entry->mDocumentEntries.AppendElement();
+  documentEntry->mCacheKey = aCacheKey;
+  documentEntry->mRuleProcessor = aRuleProcessor;
+  aRuleProcessor->SetInRuleProcessorCache(true);
+}
+
+#ifdef DEBUG
+bool
+RuleProcessorCache::DoHasRuleProcessor(nsCSSRuleProcessor* aRuleProcessor)
+{
+  for (Entry& e : mEntries) {
+    for (DocumentEntry& de : e.mDocumentEntries) {
+      if (de.mRuleProcessor == aRuleProcessor) {
+        return true;
+      }
+    }
+  }
+  return false;
+}
+#endif
+
+void
+RuleProcessorCache::DoRemoveRuleProcessor(nsCSSRuleProcessor* aRuleProcessor)
+{
+  MOZ_ASSERT(aRuleProcessor->IsInRuleProcessorCache());
+
+  aRuleProcessor->SetInRuleProcessorCache(false);
+  mExpirationTracker.RemoveObjectIfTracked(aRuleProcessor);
+  for (Entry& e : mEntries) {
+    for (size_t i = 0; i < e.mDocumentEntries.Length(); i++) {
+      if (e.mDocumentEntries[i].mRuleProcessor == aRuleProcessor) {
+        e.mDocumentEntries.RemoveElementAt(i);
+        return;
+      }
+    }
+  }
+
+  MOZ_ASSERT_UNREACHABLE("should have found rule processor");
+}
+
+void
+RuleProcessorCache::DoStartTracking(nsCSSRuleProcessor* aRuleProcessor)
+{
+  mExpirationTracker.AddObject(aRuleProcessor);
+}
+
+void
+RuleProcessorCache::DoStopTracking(nsCSSRuleProcessor* aRuleProcessor)
+{
+  mExpirationTracker.RemoveObjectIfTracked(aRuleProcessor);
+}
+
+size_t
+RuleProcessorCache::SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf)
+{
+  size_t n = aMallocSizeOf(this);
+
+  int count = 0;
+  n += mEntries.ShallowSizeOfExcludingThis(aMallocSizeOf);
+  for (Entry& e : mEntries) {
+    n += e.mDocumentEntries.ShallowSizeOfExcludingThis(aMallocSizeOf);
+    for (DocumentEntry& de : e.mDocumentEntries) {
+      count++;
+      n += de.mRuleProcessor->SizeOfIncludingThis(aMallocSizeOf);
+    }
+  }
+
+  return n;
+}
+
+void
+RuleProcessorCache::ExpirationTracker::RemoveObjectIfTracked(
+    nsCSSRuleProcessor* aRuleProcessor)
+{
+  if (aRuleProcessor->GetExpirationState()->IsTracked()) {
+    RemoveObject(aRuleProcessor);
+  }
+}
+
+bool RuleProcessorCache::gShutdown = false;
+mozilla::StaticRefPtr<RuleProcessorCache> RuleProcessorCache::gRuleProcessorCache;