Correct the logic of dataflow framework.

build.gradle

@@ -829,6 +829,7 @@ subprojects {
 
             if (project.name.is('dataflow')) {
                 dependsOn('liveVariableTest')
+                dependsOn('issue3447Test')
             }
         }
 

dataflow/build.gradle

@@ -59,3 +59,21 @@ task liveVariableTest(dependsOn: compileTestJava, group: 'Verification') {
         }
     }
 }
+
+task issue3447Test(dependsOn: compileTestJava, group: 'Verification') {
+    description 'Test issue 3447 test case for backward analysis.'
+    inputs.file('tests/issue3447/Test.java')
+    delete('tests/issue3447/Out.txt')
+    delete('tests/issue3447/Test.class')
+    doLast {
+        javaexec {
+            workingDir = 'tests/issue3447'
+            if (!JavaVersion.current().java9Compatible) {
+                jvmArgs += "-Xbootclasspath/p:${configurations.javacJar.asPath}"
+            }
+            classpath = sourceSets.test.compileClasspath
+            classpath += sourceSets.test.output
+            main = 'livevar.LiveVariable'
+        }
+    }
+}

dataflow/src/main/java/org/checkerframework/dataflow/analysis/BackwardAnalysisImpl.java

@@ -286,6 +286,7 @@ protected void addStoreAfter(Block pred, @Nullable Node node, S s, boolean addBl
                         (exceptionStore != null) ? exceptionStore.leastUpperBound(s) : s;
                 if (!newExceptionStore.equals(exceptionStore)) {
                     exceptionStores.put(ebPred, newExceptionStore);
+                    inputs.put(ebPred, new TransferInput<V, S>(node, this, newExceptionStore));
                     addBlockToWorklist = true;
                 }
             }
@@ -344,7 +345,8 @@ public S runAnalysisFor(
                             if (n == node && !before) {
                                 return store.getRegularStore();
                             }
-                            // Copy the store to preserve to change the state in {@link #inputs}
+                            // Copy the store to avoid changing other blocks' transfer inputs in
+                            // {@link #inputs}
                             TransferResult<V, S> transferResult =
                                     callTransferFunction(n, store.copy());
                             if (n == node) {
@@ -370,8 +372,10 @@ public S runAnalysisFor(
                             return transferInput.getRegularStore();
                         }
                         setCurrentNode(node);
+                        // Copy the store to avoid changing other blocks' transfer inputs in {@link
+                        // #inputs}
                         TransferResult<V, S> transferResult =
-                                callTransferFunction(node, transferInput);
+                                callTransferFunction(node, transferInput.copy());
                         // Merge transfer result with the exception store of this exceptional block
                         S exceptionStore = exceptionStores.get(eb);
                         return exceptionStore == null

dataflow/src/main/java/org/checkerframework/dataflow/analysis/ForwardAnalysisImpl.java

@@ -282,7 +282,8 @@ public S runAnalysisFor(
                             if (cache != null && cache.containsKey(n)) {
                                 transferResult = cache.get(n);
                             } else {
-                                // Copy the store to preserve to change the state in the cache
+                                // Copy the store to avoid changing other blocks' transfer inputs in
+                                // {@link #inputs}
                                 transferResult = callTransferFunction(n, store.copy());
                                 if (cache != null) {
                                     cache.put(n, transferResult);
@@ -312,8 +313,10 @@ public S runAnalysisFor(
                             return transferInput.getRegularStore();
                         }
                         setCurrentNode(node);
+                        // Copy the store to avoid changing other blocks' transfer inputs in {@link
+                        // #inputs}
                         TransferResult<V, S> transferResult =
-                                callTransferFunction(node, transferInput);
+                                callTransferFunction(node, transferInput.copy());
                         return transferResult.getRegularStore();
                     }
                 default:

dataflow/tests/issue3447/Test.java

@@ -0,0 +1,12 @@
+// Test case for Issue 3447:
+// https://github.com/typetools/checker-framework/issues/3447
+
+public class Test {
+    public void test() throws Exception {
+        try {
+            int[] myNumbers = {1};
+            System.out.println(myNumbers[1]);
+        } catch (Exception e) {
+        }
+    }
+}