Merge pull request #8 from DanielSperry/master

Fixed problem with the restore order of variables initialized with NULL.
electronicarts · Nov 1, 2016 · 8a554c8 · 8a554c8
2 parents 2d253ec + 49a64db
commit 8a554c8
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Showing 2 changed files with 45 additions and 6 deletions.
diff --git a/async/src/main/java/com/ea/async/instrumentation/Transformer.java b/async/src/main/java/com/ea/async/instrumentation/Transformer.java
@@ -1521,6 +1521,7 @@ private void restoreStackAndLocals(final ClassNode classNode, final MethodNode o
             }
         }
         // push the arguments that must be copied to locals
+        // must only push
         for (int iLocal = 0; iLocal < frame.getLocals(); iLocal += valueSize(frame.getLocal(iLocal)))
         {
             final BasicValue value = frame.getLocal(iLocal);
@@ -1531,20 +1532,26 @@ private void restoreStackAndLocals(final ClassNode classNode, final MethodNode o
                     mv.visitVarInsn(value.getType().getOpcode(ILOAD), se.localToiArgument[iLocal]);
                 }
             }
-            else if (value != null && value.getType() != null)
-            {
-                pushDefault(mv, value);
-                mv.visitVarInsn(value.getType().getOpcode(ISTORE), iLocal);
-            }
         }
-        // push the arguments that must be copied to locals
+        // stores the values that came from arguments
         for (int iLocal = frame.getLocals(); --iLocal >= 0; )
         {
             if (se.localToiArgument[iLocal] >= 0 && se.localToiArgument[iLocal] != iLocal)
             {
                 mv.visitVarInsn(frame.getLocal(iLocal).getType().getOpcode(ISTORE), iLocal);
             }
         }
+        // restore values that were initialized as constants (i.e.: ACONST_NULL)
+        for (int iLocal = 0; iLocal < frame.getLocals(); iLocal += valueSize(frame.getLocal(iLocal)))
+        {
+            final BasicValue value = frame.getLocal(iLocal);
+            if (se.localToiArgument[iLocal] < 0 && value != null && value.getType() != null)
+            {
+                pushDefault(mv, value);
+                mv.visitVarInsn(value.getType().getOpcode(ISTORE), iLocal);
+            }
+        }
+
         // reacquire monitors
         for (int i = 0; i < se.frame.monitors.length; i++)
         {

diff --git a/async/src/test/java/com/ea/async/test/NullThenBasicValueTest.java b/async/src/test/java/com/ea/async/test/NullThenBasicValueTest.java
@@ -0,0 +1,32 @@
+package com.ea.async.test;
+
+import com.ea.async.Task;
+
+import org.junit.Test;
+
+import static com.ea.async.Async.await;
+import static org.junit.Assert.assertNull;
+
+public class NullThenBasicValueTest extends BaseTest
+{
+    @Test
+    public void nullThenBasicValueTest() throws Exception
+    {
+        debugTransform(NullThenBasicValueTest.class.getName() + "$NullThenBasicVal");
+        final Task<Void> res = NullThenBasicVal.doIt(getBlockedTask());
+        completeFutures();
+        assertNull(res.join());
+    }
+
+    public static class NullThenBasicVal
+    {
+        public static Task<Void> doIt(Task<Void> task)
+        {
+            String nullString = null; //this variable must be a string and initialized to null
+            int basicInt = 0; //this variable must be numeric and initialized to anything
+
+            await(task);
+            return Task.done();
+        }
+    }
+}