Fix synchronization of our dual lattice generation
Basically, the call to getOrCreateDualLattice should not be done while we
are synchronized on the DexType, since other paths to getInterfaces can
lock this at the same time
Bug: 120435694
Change-Id: I25498b454628cb0cede87926f82db8279e25903a
diff --git a/src/main/java/com/android/tools/r8/graph/DexItemFactory.java b/src/main/java/com/android/tools/r8/graph/DexItemFactory.java
index e9966f5..1c04f9d 100644
--- a/src/main/java/com/android/tools/r8/graph/DexItemFactory.java
+++ b/src/main/java/com/android/tools/r8/graph/DexItemFactory.java
@@ -993,13 +993,14 @@
public ReferenceTypeLatticeElement createReferenceTypeLatticeElement(
DexType type, boolean isNullable, AppInfo appInfo) {
+ ReferenceTypeLatticeElement typeLattice = referenceTypeLatticeElements.get(type);
+ if (typeLattice != null) {
+ return isNullable == typeLattice.isNullable() ? typeLattice
+ : typeLattice.getOrCreateDualLattice();
+ }
synchronized (type) {
- ReferenceTypeLatticeElement typeLattice = referenceTypeLatticeElements.get(type);
- if (typeLattice != null) {
- typeLattice = isNullable == typeLattice.isNullable() ? typeLattice
- : typeLattice.getOrCreateDualLattice();
- assert typeLattice.isNullable() == isNullable;
- } else {
+ typeLattice = referenceTypeLatticeElements.get(type);
+ if (typeLattice == null) {
if (type.isClassType()) {
if (!type.isUnknown() && type.isInterface()) {
typeLattice = new ClassTypeLatticeElement(
@@ -1020,9 +1021,11 @@
}
referenceTypeLatticeElements.put(type, typeLattice);
}
- assert typeLattice.isNullable() == isNullable;
- return typeLattice;
}
+ // The call to getOrCreateDualLattice can't be under the DexType synchronized block, since that
+ // can create deadlocks with ClassTypeLatticeElement::getInterfaces (both lock on the lattice).
+ return isNullable == typeLattice.isNullable() ? typeLattice
+ : typeLattice.getOrCreateDualLattice();
}
private static <S extends PresortedComparable<S>> void assignSortedIndices(Collection<S> items,
