Add test for bug in nullness analysis

core/src/test/java/org/teavm/model/analysis/test/NullnessAnalysisTest.java

@@ -29,6 +29,7 @@ import java.io.InputStreamReader;
 import java.nio.charset.StandardCharsets;
 import java.util.HashMap;
 import java.util.Map;
+import org.junit.Ignore;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TestName;
@@ -84,6 +85,12 @@ public class NullnessAnalysisTest {
         test();
     }
 
+    @Test
+    @Ignore
+    public void nonDominatedBranch2() {
+        test();
+    }
+
     @Test
     public void exception() {
         test();

core/src/test/resources/model/analysis/nullness/nonDominatedBranch2.extended.txt

@@ -0,0 +1,10 @@
+var @this as this // 0
+$0
+    @a := invokeStatic `Foo.f()LBar;`
+    if @a === null then goto $2 else goto $1
+$1
+    goto $2
+$2
+    @c := phi @a_1 from $0, @a_2 from $1
+    @d := @a
+    return @c

core/src/test/resources/model/analysis/nullness/nonDominatedBranch2.original.txt

@@ -0,0 +1,11 @@
+var @this as this
+
+$start
+    @a := invokeStatic `Foo.f()LBar;`
+    if @a === null then goto $joint else goto $ifNonNull
+$ifNonNull
+    goto $joint
+$joint
+    @c := phi @a from $start, @a from $ifNonNull
+    @d := @a
+    return @c