Add config version, and invalidate layout on config change

packages/react-native/ReactCommon/yoga/yoga/algorithm/CalculateLayout.cpp

@@ -2140,6 +2140,7 @@ bool calculateLayoutInternal(
 
   const bool needToVisitNode =
       (node->isDirty() && layout->generationCount != generationCount) ||
+      layout->configVersion != node->getConfig()->getVersion() ||
       layout->lastOwnerDirection != ownerDirection;
 
   if (needToVisitNode) {
@@ -2255,6 +2256,7 @@ bool calculateLayoutInternal(
         reason);
 
     layout->lastOwnerDirection = ownerDirection;
+    layout->configVersion = node->getConfig()->getVersion();
 
     if (cachedResults == nullptr) {
       layoutMarkerData.maxMeasureCache = std::max(

packages/react-native/ReactCommon/yoga/yoga/config/Config.cpp

@@ -31,7 +31,10 @@ bool Config::useWebDefaults() const {
 void Config::setExperimentalFeatureEnabled(
     ExperimentalFeature feature,
     bool enabled) {
-  experimentalFeatures_.set(static_cast<size_t>(feature), enabled);
+  if (isExperimentalFeatureEnabled(feature) != enabled) {
+    experimentalFeatures_.set(static_cast<size_t>(feature), enabled);
+    version_++;
+  }
 }
 
 bool Config::isExperimentalFeatureEnabled(ExperimentalFeature feature) const {
@@ -43,15 +46,24 @@ ExperimentalFeatureSet Config::getEnabledExperiments() const {
 }
 
 void Config::setErrata(Errata errata) {
-  errata_ = errata;
+  if (errata_ != errata) {
+    errata_ = errata;
+    version_++;
+  }
 }
 
 void Config::addErrata(Errata errata) {
-  errata_ |= errata;
+  if (!hasErrata(errata)) {
+    errata_ |= errata;
+    version_++;
+  }
 }
 
 void Config::removeErrata(Errata errata) {
-  errata_ &= (~errata);
+  if (hasErrata(errata)) {
+    errata_ &= (~errata);
+    version_++;
+  }
 }
 
 Errata Config::getErrata() const {
@@ -63,7 +75,10 @@ bool Config::hasErrata(Errata errata) const {
 }
 
 void Config::setPointScaleFactor(float pointScaleFactor) {
-  pointScaleFactor_ = pointScaleFactor;
+  if (pointScaleFactor_ != pointScaleFactor) {
+    pointScaleFactor_ = pointScaleFactor;
+    version_++;
+  }
 }
 
 float Config::getPointScaleFactor() const {
@@ -78,6 +93,10 @@ void* Config::getContext() const {
   return context_;
 }
 
+uint32_t Config::getVersion() const noexcept {
+  return version_;
+}
+
 void Config::setLogger(YGLogger logger) {
   logger_ = logger;
 }

packages/react-native/ReactCommon/yoga/yoga/config/Config.h

@@ -53,6 +53,8 @@ class YG_EXPORT Config : public ::YGConfig {
   void setContext(void* context);
   void* getContext() const;
 
+  uint32_t getVersion() const noexcept;
+
   void setLogger(YGLogger logger);
   void log(
       const yoga::Node* node,
@@ -72,6 +74,7 @@ class YG_EXPORT Config : public ::YGConfig {
 
   bool useWebDefaults_ : 1 = false;
 
+  uint32_t version_ = 0;
   ExperimentalFeatureSet experimentalFeatures_{};
   Errata errata_ = Errata::None;
   float pointScaleFactor_ = 1.0f;

packages/react-native/ReactCommon/yoga/yoga/node/LayoutResults.cpp

@@ -21,6 +21,7 @@ bool LayoutResults::operator==(LayoutResults layout) const {
       direction() == layout.direction() &&
       hadOverflow() == layout.hadOverflow() &&
       lastOwnerDirection == layout.lastOwnerDirection &&
+      configVersion == layout.configVersion &&
       nextCachedMeasurementsIndex == layout.nextCachedMeasurementsIndex &&
       cachedLayout == layout.cachedLayout &&
       computedFlexBasis == layout.computedFlexBasis;

packages/react-native/ReactCommon/yoga/yoga/node/LayoutResults.h

@@ -30,6 +30,7 @@ struct LayoutResults {
   // Instead of recomputing the entire layout every single time, we cache some
   // information to break early when nothing changed
   uint32_t generationCount = 0;
+  uint32_t configVersion = 0;
   Direction lastOwnerDirection = Direction::Inherit;
 
   uint32_t nextCachedMeasurementsIndex = 0;

packages/react-native/ReactCommon/yoga/yoga/node/Node.cpp

@@ -136,6 +136,11 @@ void Node::setConfig(yoga::Config* config) {
 
   if (yoga::configUpdateInvalidatesLayout(*config_, *config)) {
     markDirtyAndPropagate();
+    layout_.configVersion = 0;
+  } else {
+    // If the config is functionally the same, then align the configVersion so
+    // that we can reuse the layout cache
+    layout_.configVersion = config->getVersion();
   }
 
   config_ = config;