commit eb2d2d346e9506e5fe2c8e1e72a146821192b973
author Mingyao Yang <mingyao@google.com> Thu Mar 02 13:26:17 2017 -0800
committer Mingyao Yang <mingyao@google.com> Wed Mar 08 12:56:41 2017 -0800
tree 3c7b7f1cac227248aaf9ac313825a6a71ae4c66e
parent caa348cee1312150a957bd308ce77ad406f3eb64

Allow store elimination for singleton that's returned

Allow store elimination for singleton that's visible after method return
or deoptimization. Add additional detection for keeping stores for such
singletons at block merge/deoptimization point.

Bug: 35745320
Test: m test-art-host
Change-Id: I8a75a304491dafaeb689787402afa3d7468e3789

test/530-checker-lse/src/Main.java

diff --git a/test/530-checker-lse/src/Main.java b/test/530-checker-lse/src/Main.java
index 14a40ef..6632503 100644
--- a/test/530-checker-lse/src/Main.java
+++ b/test/530-checker-lse/src/Main.java
@@ -747,6 +747,69 @@
     return 1.0f;
   }
 
+  /// CHECK-START: TestClass2 Main.testStoreStore() load_store_elimination (before)
+  /// CHECK: NewInstance
+  /// CHECK: InstanceFieldSet
+  /// CHECK: InstanceFieldSet
+  /// CHECK: InstanceFieldSet
+  /// CHECK: InstanceFieldSet
+
+  /// CHECK-START: TestClass2 Main.testStoreStore() load_store_elimination (after)
+  /// CHECK: NewInstance
+  /// CHECK: InstanceFieldSet
+  /// CHECK: InstanceFieldSet
+  /// CHECK-NOT: InstanceFieldSet
+
+  private static TestClass2 testStoreStore() {
+    TestClass2 obj = new TestClass2();
+    obj.i = 41;
+    obj.j = 42;
+    obj.i = 41;
+    obj.j = 43;
+    return obj;
+  }
+
+  /// CHECK-START: int Main.testStoreStoreWithDeoptimize(int[]) load_store_elimination (before)
+  /// CHECK: NewInstance
+  /// CHECK: InstanceFieldSet
+  /// CHECK: InstanceFieldSet
+  /// CHECK: InstanceFieldSet
+  /// CHECK: InstanceFieldSet
+  /// CHECK: Deoptimize
+  /// CHECK: ArraySet
+  /// CHECK: ArraySet
+  /// CHECK: ArraySet
+  /// CHECK: ArraySet
+  /// CHECK: ArrayGet
+  /// CHECK: ArrayGet
+  /// CHECK: ArrayGet
+  /// CHECK: ArrayGet
+
+  /// CHECK-START: int Main.testStoreStoreWithDeoptimize(int[]) load_store_elimination (after)
+  /// CHECK: NewInstance
+  /// CHECK: InstanceFieldSet
+  /// CHECK: InstanceFieldSet
+  /// CHECK-NOT: InstanceFieldSet
+  /// CHECK: Deoptimize
+  /// CHECK: ArraySet
+  /// CHECK: ArraySet
+  /// CHECK: ArraySet
+  /// CHECK: ArraySet
+  /// CHECK-NOT: ArrayGet
+
+  private static int testStoreStoreWithDeoptimize(int[] arr) {
+    TestClass2 obj = new TestClass2();
+    obj.i = 41;
+    obj.j = 42;
+    obj.i = 41;
+    obj.j = 43;
+    arr[0] = 1;  // One HDeoptimize here.
+    arr[1] = 1;
+    arr[2] = 1;
+    arr[3] = 1;
+    return arr[0] + arr[1] + arr[2] + arr[3];
+  }
+
   /// CHECK-START: double Main.getCircleArea(double, boolean) load_store_elimination (before)
   /// CHECK: NewInstance
 
@@ -950,6 +1013,10 @@
     assertIntEquals(testAllocationEliminationOfArray2(), 11);
     assertIntEquals(testAllocationEliminationOfArray3(2), 4);
     assertIntEquals(testAllocationEliminationOfArray4(2), 6);
+
+    assertIntEquals(testStoreStore().i, 41);
+    assertIntEquals(testStoreStore().j, 43);
+    assertIntEquals(testStoreStoreWithDeoptimize(new int[4]), 4);
   }
 
   static boolean sFlag;