Fix ARM64 Baker's read barrier fast path for ArraySet.

Do not exhaust the pool of scratch (temporary) registers
gratuitously when emitting an instrumented array load with a
large constant index.

Bug: 26817006
Bug: 12687968
Change-Id: I65a4fe676aa3c9e2c8d7e26195d9af6432c83ff9

1 files changed, 60 insertions, 0 deletions

diff --git a/test/572-checker-array-get-regression/src/Main.java b/test/572-checker-array-get-regression/src/Main.java
new file mode 100644
index 0000000000..bc13af9683
--- /dev/null
+++ b/test/572-checker-array-get-regression/src/Main.java
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+public class Main {
+
+  public static void main(String[] args) {
+    System.out.println(test().intValue());
+  }
+
+  /// CHECK-START: java.lang.Integer Main.test() ssa_builder (after)
+  /// CHECK-DAG:     <<Method:j\d+>>       CurrentMethod
+  /// CHECK-DAG:     <<Const2P20:i\d+>>    IntConstant 1048576
+  /// CHECK-DAG:     <<ConstM1:i\d+>>      IntConstant -1
+  /// CHECK-DAG:     <<Array:l\d+>>        NewArray [<<Const2P20>>,<<Method>>]
+  /// CHECK-DAG:     <<NullCheck1:l\d+>>   NullCheck [<<Array>>]
+  /// CHECK-DAG:     <<Length1:i\d+>>      ArrayLength [<<NullCheck1>>]
+  /// CHECK-DAG:     <<Index:i\d+>>        Add [<<Length1>>,<<ConstM1>>]
+  /// CHECK-DAG:     <<NullCheck2:l\d+>>   NullCheck [<<Array>>]
+  /// CHECK-DAG:     <<Length2:i\d+>>      ArrayLength [<<NullCheck2>>]
+  /// CHECK-DAG:     <<BoundsCheck:i\d+>>  BoundsCheck [<<Index>>,<<Length2>>]
+  /// CHECK-DAG:     <<LastElement:l\d+>>  ArrayGet [<<NullCheck2>>,<<BoundsCheck>>]
+  /// CHECK-DAG:                           Return [<<LastElement>>]
+
+  /// CHECK-START: java.lang.Integer Main.test() register (before)
+  /// CHECK-DAG:     <<Method:j\d+>>       CurrentMethod
+  /// CHECK-DAG:     <<Const2P20:i\d+>>    IntConstant 1048576
+  /// CHECK-DAG:     <<Const2P20M1:i\d+>>  IntConstant 1048575
+  /// CHECK-DAG:     <<Array:l\d+>>        NewArray [<<Const2P20>>,<<Method>>]
+  /// CHECK-DAG:     <<LastElement:l\d+>>  ArrayGet [<<Array>>,<<Const2P20M1>>]
+  /// CHECK-DAG:                           Return [<<LastElement>>]
+
+  public static Integer test() {
+    Integer[] integers = new Integer[1024 * 1024];
+    initIntegerArray(integers);
+    // Array load with a large constant index (after constant folding
+    // and bounds check elimination).
+    Integer last_integer = integers[integers.length - 1];
+    return last_integer;
+  }
+
+  public static void initIntegerArray(Integer[] integers) {
+    for (int i = 0; i < integers.length; ++i) {
+      integers[i] = new Integer(i);
+    }
+  }
+
+}