commit 1a6b23bd5d97a0ff2a6464d1921455f6b3b0d740
author Christoffer Quist Adamsen <christofferqa@google.com> Tue May 30 12:57:51 2023 +0200
committer Christoffer Quist Adamsen <christofferqa@google.com> Tue May 30 12:57:51 2023 +0200
tree bc27953512cfccc0af6c070f16851116dea7150c
parent 3c496ba2ac10dbf6f8870671f92336969893ca15

Fix inadequate argument propagation in presence of join types

Bug: b/284188592
Change-Id: Ic00ce43da9839884cbb19a87a7b43020951c3114

src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/VirtualDispatchMethodArgumentPropagator.java

diff --git a/src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/VirtualDispatchMethodArgumentPropagator.java b/src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/VirtualDispatchMethodArgumentPropagator.java
index a1aec5a..313b6ca 100644
--- a/src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/VirtualDispatchMethodArgumentPropagator.java
+++ b/src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/VirtualDispatchMethodArgumentPropagator.java
@@ -170,7 +170,14 @@
           && currentClass.getSuperType() != appView.dexItemFactory().objectType) {
         return classType.lessThanOrEqualUpToNullability(upperBound, appView);
       }
-      return classType.equalUpToNullability(upperBound);
+      // If the upper bound does not have any interfaces we simply activate the method state when
+      // meeting the upper bound class type in the downwards traversal over the class hierarchy.
+      if (classType.getInterfaces().isEmpty()) {
+        return classType.equalUpToNullability(upperBound);
+      }
+      // If the upper bound has interfaces, we check if the current class is a subtype of *both* the
+      // upper bound class type and the upper bound interface types.
+      return classType.lessThanOrEqualUpToNullability(upperBound, appView);
     }
   }
 

src/test/java/com/android/tools/r8/optimize/argumentpropagation/ArgumentPropagationUpperBoundWithInterfacesTest.java

diff --git a/src/test/java/com/android/tools/r8/optimize/argumentpropagation/ArgumentPropagationUpperBoundWithInterfacesTest.java b/src/test/java/com/android/tools/r8/optimize/argumentpropagation/ArgumentPropagationUpperBoundWithInterfacesTest.java
index 1c1e45a..7ac6f56 100644
--- a/src/test/java/com/android/tools/r8/optimize/argumentpropagation/ArgumentPropagationUpperBoundWithInterfacesTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/argumentpropagation/ArgumentPropagationUpperBoundWithInterfacesTest.java
@@ -45,8 +45,7 @@
         .setMinApi(parameters)
         .compile()
         .run(parameters.getRuntime(), Main.class)
-        // TODO(b/284188592): Should succeed with "42".
-        .assertFailureWithErrorThatThrows(NullPointerException.class);
+        .assertSuccessWithOutputLines("42");
   }
 
   static class Main {