R8在Android手Q中的应用

com.android.tools.r8.shaking.Enqueuer.markDirectClassInitializerAsLive(Enqueuer.java:1831)
com.android.tools.r8.shaking.Enqueuer.markDirectAndIndirectClassInitializersAsLive(Enqueuer.java:1776)
com.android.tools.r8.shaking.Enqueuer.processNewlyInstantiatedClass(Enqueuer.java:2032)

private void markDirectAndIndirectClassInitializersAsLive(DexProgramClass clazz) {
    Deque<DexProgramClass> worklist = DequeUtils.newArrayDeque(clazz);
    Set<DexProgramClass> visited = SetUtils.newIdentityHashSet(clazz);
    while (!worklist.isEmpty()) {
      DexProgramClass current = worklist.removeFirst();
      assert visited.contains(current);
      // 这里很关键，如果已经添加过，则不会走下面对父类的分析
      if (!markDirectClassInitializerAsLive(current)) {
        continue;
      }
      // Mark all class initializers in all super types as live.
      for (DexType superType : clazz.allImmediateSupertypes()) {
        DexProgramClass superClass = getProgramClassOrNull(superType);
        if (superClass != null && visited.add(superClass)) {
          worklist.add(superClass);
        }
      }
    }
  }

/** Returns true if the class initializer became live for the first time. */
  private boolean markDirectClassInitializerAsLive(DexProgramClass clazz) {
    ProgramMethod clinit = clazz.getProgramClassInitializer();
    KeepReasonWitness witness = graphReporter.reportReachableClassInitializer(clazz, clinit);
    if (!initializedTypes.add(clazz, witness)) {
      return false;
    }
    if (clinit != null && clinit.getDefinition().getOptimizationInfo().mayHaveSideEffects()) {
      markDirectStaticOrConstructorMethodAsLive(clinit, witness);
    }
    return true;
  }

private void markDirectAndIndirectClassInitializersAsLive(DexProgramClass clazz) {
    if (clazz.isInterface()) {
      // Accessing a static field or method on an interface does not trigger the class initializer
      // of any parent interfaces.
      markInterfaceInitializedDirectly(clazz);
      return;
    }

    WorkList<DexProgramClass> worklist = WorkList.newIdentityWorkList(clazz);
    while (worklist.hasNext()) {
      DexProgramClass current = worklist.next();
      if (current.isInterface()) {
        // 新增逻辑，加载Interface的clinit方法，可以解决低版本的问题
        if (!markInterfaceInitializedIndirectly(current)) {
          continue;
        }
      } else {
        if (!markDirectClassInitializerAsLive(current)) {
          continue;
        }
      }
      // Mark all class initializers in all super types as live.
      for (DexType superType : current.allImmediateSupertypes()) {
        DexProgramClass superClass = getProgramClassOrNull(superType, current);
        if (superClass != null) {
          worklist.addIfNotSeen(superClass);
        }
      }
    }
  }

行 122967: 2021-12-20 20:43:22:634 : MinifyFields printRecordData 
行 122968: 2021-12-20 20:53:29:834 : MinifyIdentifiers printRecordData 

    void includeReservations(InternalState state) {
      reservedNamesDirect.putAll(state.reservedNamesDirect);
    }

public void putAll(Map<? extends K, ? extends V> m) {
        int n = m.size();
        if (n != 0) {
            if (n > this.size) {
                this.resize(capacity(n));
            }
            Iterator var3 = m.entrySet().iterator();
            while(var3.hasNext()) {
                java.util.Map.Entry<? extends K, ? extends V> e = (java.util.Map.Entry)var3.next();
                this.put(e.getKey(), e.getValue());
            }
        }
    }

diff --git a/src/main/java/com/android/tools/r8/naming/FieldNameMinifier.java b/src/main/java/com/android/tools/r8/naming/FieldNameMinifier.java
index bec8073a8..667459f17 100644
--- a/src/main/java/com/android/tools/r8/naming/FieldNameMinifier.java
+++ b/src/main/java/com/android/tools/r8/naming/FieldNameMinifier.java
@@ -235,7 +235,7 @@ class FieldNameMinifier {
         DexClass implementation = appView.definitionFor(implementationType);
         if (implementation != null) {
           getOrCreateReservedFieldNamingState(implementationType)
-              .includeReservations(namesToBeReservedInImplementsSubclasses);
+              .setSubclassesReservednames(namesToBeReservedInImplementsSubclasses);
         }
       }
     }
diff --git a/src/main/java/com/android/tools/r8/naming/ReservedFieldNamingState.java b/src/main/java/com/android/tools/r8/naming/ReservedFieldNamingState.java
index 4e3e98c40..a074a2ace 100644
--- a/src/main/java/com/android/tools/r8/naming/ReservedFieldNamingState.java
+++ b/src/main/java/com/android/tools/r8/naming/ReservedFieldNamingState.java
@@ -14,6 +14,13 @@ import java.util.Map;
 
 class ReservedFieldNamingState extends FieldNamingStateBase<InternalState> {
 
+  /*
+   Reference to namesToBeReservedInImplementsSubclasses in the renameFieldsInInterfacePartition method,
+   the purpose is to reduce copying
+   @see FieldNameMinifier#namesToBeReservedInImplementsSubclasses(Set<DexClass> partition)
+ */
+  ReservedFieldNamingState  subclassesReservednames;
+
   ReservedFieldNamingState(AppView<? extends AppInfoWithClassHierarchy> appView) {
     super(appView, new IdentityHashMap<>());
   }
@@ -24,7 +31,11 @@ class ReservedFieldNamingState extends FieldNamingStateBase<InternalState> {
 
   DexString getReservedByName(DexString name, DexType type) {
     InternalState internalState = getInternalState(type);
-    return internalState == null ? null : internalState.getReservedByName(name);
+    DexString result = internalState == null ? null : internalState.getReservedByName(name);
+    if(result == null && subclassesReservednames!=null){
+      result = subclassesReservednames.getReservedByName(name, type);
+    }
+    return result;
   }
 
   void markReservedDirectly(DexString name, DexString originalName, DexType type) {
@@ -35,6 +46,7 @@ class ReservedFieldNamingState extends FieldNamingStateBase<InternalState> {
     for (Map.Entry<DexType, InternalState> entry : reservedNames.internalStates.entrySet()) {
       getOrCreateInternalState(entry.getKey()).includeReservations(entry.getValue());
     }
+    this.subclassesReservednames = reservedNames.subclassesReservednames;
   }
 
   void includeReservationsFromBelow(ReservedFieldNamingState reservedNames) {
@@ -43,6 +55,10 @@ class ReservedFieldNamingState extends FieldNamingStateBase<InternalState> {
     }
   }
 
+  void setSubclassesReservednames(ReservedFieldNamingState reservedNames ) {
+    this.subclassesReservednames = reservedNames.subclassesReservednames;
+  }
+
   @Override
   InternalState createInternalState() {
     return new InternalState();