For LSE, further optimize stores for singleton references.
Loop side effects shouldn't affect singletons whose fields are never stored into
inside a loop.
Change-Id: If3715d7b7e621bb077ef9481072a56f7fec87f2b
diff --git a/test/530-checker-lse/src/Main.java b/test/530-checker-lse/src/Main.java
index 7d89372..cadf706 100644
--- a/test/530-checker-lse/src/Main.java
+++ b/test/530-checker-lse/src/Main.java
@@ -489,27 +489,32 @@
return obj;
}
- /// CHECK-START: void Main.test21() load_store_elimination (before)
+ /// CHECK-START: void Main.test21(TestClass) load_store_elimination (before)
/// CHECK: NewInstance
/// CHECK: InstanceFieldSet
- /// CHECK: StaticFieldSet
- /// CHECK: StaticFieldGet
+ /// CHECK: InstanceFieldSet
+ /// CHECK: InstanceFieldSet
+ /// CHECK: InstanceFieldGet
+ /// CHECK: InstanceFieldGet
- /// CHECK-START: void Main.test21() load_store_elimination (after)
+ /// CHECK-START: void Main.test21(TestClass) load_store_elimination (after)
/// CHECK: NewInstance
/// CHECK: InstanceFieldSet
- /// CHECK: StaticFieldSet
+ /// CHECK: InstanceFieldSet
+ /// CHECK: InstanceFieldSet
+ /// CHECK: InstanceFieldGet
/// CHECK: InstanceFieldGet
// Loop side effects can kill heap values, stores need to be kept in that case.
- static void test21() {
+ static void test21(TestClass obj0) {
TestClass obj = new TestClass();
+ obj0.str = "abc";
obj.str = "abc";
for (int i = 0; i < 2; i++) {
- // Generate some loop side effect that does write.
- obj.si = 1;
+ // Generate some loop side effect that writes into obj.
+ obj.str = "def";
}
- System.out.print(obj.str.substring(0, 0));
+ System.out.print(obj0.str.substring(0, 0) + obj.str.substring(0, 0));
}
/// CHECK-START: int Main.test22() load_store_elimination (before)
@@ -525,27 +530,29 @@
/// CHECK-START: int Main.test22() load_store_elimination (after)
/// CHECK: NewInstance
- /// CHECK: InstanceFieldSet
+ /// CHECK-NOT: InstanceFieldSet
/// CHECK: NewInstance
/// CHECK-NOT: InstanceFieldSet
/// CHECK-NOT: InstanceFieldGet
/// CHECK: NewInstance
/// CHECK-NOT: InstanceFieldSet
- /// CHECK: InstanceFieldGet
+ /// CHECK-NOT: InstanceFieldGet
/// CHECK-NOT: InstanceFieldGet
- // Loop side effects only affects stores into singletons that dominiates the loop header.
+ // For a singleton, loop side effects can kill its field values only if:
+ // (1) it dominiates the loop header, and
+ // (2) its fields are stored into inside a loop.
static int test22() {
int sum = 0;
TestClass obj1 = new TestClass();
- obj1.i = 2; // This store can't be eliminated since it can be killed by loop side effects.
+ obj1.i = 2; // This store can be eliminated since obj1 is never stored into inside a loop.
for (int i = 0; i < 2; i++) {
TestClass obj2 = new TestClass();
- obj2.i = 3; // This store can be eliminated since the singleton is inside the loop.
+ obj2.i = 3; // This store can be eliminated since the singleton is inside the loop.
sum += obj2.i;
}
TestClass obj3 = new TestClass();
- obj3.i = 5; // This store can be eliminated since the singleton is created after the loop.
+ obj3.i = 5; // This store can be eliminated since the singleton is created after the loop.
sum += obj1.i + obj3.i;
return sum;
}
@@ -715,7 +722,7 @@
float[] fa2 = { 1.8f };
assertFloatEquals(test19(fa1, fa2), 1.8f);
assertFloatEquals(test20().i, 0);
- test21();
+ test21(new TestClass());
assertIntEquals(test22(), 13);
assertIntEquals(test23(true), 4);
assertIntEquals(test23(false), 5);