ART: Remove old aget on null workaround

Use null for an aget-object of null. Ensure that other aget types
on null cannot be converted to or used as a reference type.

Let the verifier continue scanning after an aget on a null register,
to ensure that the dead code is type-safe.

Add test coverage for the new behavior.

Partially reverts commit 4824c27988c8eeb302791624bb3ce1d557b0db6c
Partially reverts commit 857f058d4b7bd07c5c99eda416ad91516a10b4da

Bug: 22059710
Bug: 64683522
Bug: 69669661
Test: m test-art-host
Change-Id: Ie0b554e8f880251d8e73ab6dfb6b41a5e63defc6

1 files changed, 28 insertions, 8 deletions

diff --git a/test/518-null-array-get/src/Main.java b/test/518-null-array-get/src/Main.java
index 66e50aacd7..678aef1f43 100644
--- a/test/518-null-array-get/src/Main.java
+++ b/test/518-null-array-get/src/Main.java
@@ -22,16 +22,36 @@ public class Main {
   class InnerClass {}
 
   public static void main(String[] args) throws Exception {
-    Class<?> c = Class.forName("NullArray");
-    Method m = c.getMethod("method");
-    Object[] arguments = { };
+    checkLoad("NullArrayFailInt2Object", true);
+    checkLoad("NullArrayFailObject2Int", true);
+    checkLoad("NullArraySuccessInt", false);
+    checkLoad("NullArraySuccessInt2Float", false);
+    checkLoad("NullArraySuccessShort", false);
+    checkLoad("NullArraySuccessRef", false);
+  }
+
+  private static void checkLoad(String className, boolean expectError) throws Exception {
+    Class<?> c;
     try {
-      m.invoke(null, arguments);
-      throw new Error("Expected an InvocationTargetException");
-    } catch (InvocationTargetException e) {
-      if (!(e.getCause() instanceof NullPointerException)) {
-        throw new Error("Expected a NullPointerException");
+      c = Class.forName(className);
+      if (expectError) {
+        throw new RuntimeException("Expected error for " + className);
+      }
+      Method m = c.getMethod("method");
+      try {
+        m.invoke(null);
+        throw new RuntimeException("Expected an InvocationTargetException");
+      } catch (InvocationTargetException e) {
+        if (!(e.getCause() instanceof NullPointerException)) {
+          throw new RuntimeException("Expected a NullPointerException");
+        }
+        System.out.println(className);
+      }
+    } catch (VerifyError e) {
+      if (!expectError) {
+        throw new RuntimeException(e);
       }
+      System.out.println(className);
     }
   }
 }