content: /*
   * Copyright (C) 2015 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 {
  
    /// CHECK-START: int Main.div() licm (before)
    /// CHECK-DAG: Div loop:{{B\d+}}
  
    /// CHECK-START: int Main.div() licm (after)
    /// CHECK-NOT: Div loop:{{B\d+}}
  
    /// CHECK-START: int Main.div() licm (after)
    /// CHECK-DAG: Div loop:none
  
    public static int div() {
      int result = 0;
      for (int i = 0; i < 10; ++i) {
        result += staticField / 42;
      }
      return result;
    }
  
    /// CHECK-START: int Main.innerDiv() licm (before)
    /// CHECK-DAG: Div loop:{{B\d+}}
  
    /// CHECK-START: int Main.innerDiv() licm (after)
    /// CHECK-NOT: Div loop:{{B\d+}}
  
    /// CHECK-START: int Main.innerDiv() licm (after)
    /// CHECK-DAG: Div loop:none
  
    public static int innerDiv() {
      int result = 0;
      for (int i = 0; i < 10; ++i) {
        for (int j = 0; j < 10; ++j) {
          result += staticField / 42;
        }
      }
      return result;
    }
  
    /// CHECK-START: int Main.innerMul() licm (before)
    /// CHECK-DAG: Mul loop:B4
  
    /// CHECK-START: int Main.innerMul() licm (after)
    /// CHECK-DAG: Mul loop:B2
  
    public static int innerMul() {
      int result = 0;
      for (int i = 0; i < 10; ++i) {
        for (int j = 0; j < 10; ++j) {
          // The operation has been hoisted out of the inner loop.
          // Note that we depend on the compiler's block numbering to
          // check if it has been moved.
          result += staticField * i;
        }
      }
      return result;
    }
  
    /// CHECK-START: int Main.divByA(int, int) licm (before)
    /// CHECK-DAG: Div loop:{{B\d+}}
  
    /// CHECK-START: int Main.divByA(int, int) licm (after)
    /// CHECK-DAG: Div loop:{{B\d+}}
  
    public static int divByA(int a, int b) {
      int result = 0;
      while (b < 5) {
        // a might be null, so we can't hoist the operation.
        result += staticField / a;
        b++;
      }
      return result;
    }
  
    /// CHECK-START: int Main.arrayLength(int[]) licm (before)
    /// CHECK-DAG: <<NullCheck:l\d+>> NullCheck loop:{{B\d+}}
    /// CHECK-DAG:                    ArrayLength [<<NullCheck>>] loop:{{B\d+}}
  
    /// CHECK-START: int Main.arrayLength(int[]) licm (after)
    /// CHECK-NOT:                    NullCheck loop:{{B\d+}}
    /// CHECK-NOT:                    ArrayLength loop:{{B\d+}}
  
    /// CHECK-START: int Main.arrayLength(int[]) licm (after)
    /// CHECK-DAG: <<NullCheck:l\d+>> NullCheck loop:none
    /// CHECK-DAG:                    ArrayLength [<<NullCheck>>] loop:none
  
    public static int arrayLength(int[] array) {
      int result = 0;
      for (int i = 0; i < array.length; ++i) {
        result += array[i];
      }
      return result;
    }
  
    /// CHECK-START: int Main.divAndIntrinsic(int[]) licm (before)
    /// CHECK-DAG: Div loop:{{B\d+}}
  
    /// CHECK-START: int Main.divAndIntrinsic(int[]) licm (after)
    /// CHECK-NOT: Div loop:{{B\d+}}
  
    /// CHECK-START: int Main.divAndIntrinsic(int[]) licm (after)
    /// CHECK-DAG: Div loop:none
  
    public static int divAndIntrinsic(int[] array) {
      int result = 0;
      for (int i = 0; i < array.length; i++) {
        // An intrinsic call, unlike a general method call, cannot modify the field value.
        // As a result, the invariant division on the field can be moved out of the loop.
        result += (staticField / 42) + Math.abs(array[i]);
      }
      return result;
    }
  
    /// CHECK-START: int Main.invariantBoundIntrinsic(int) licm (before)
    /// CHECK-DAG: InvokeStaticOrDirect loop:{{B\d+}}
  
    /// CHECK-START: int Main.invariantBoundIntrinsic(int) licm (after)
    /// CHECK-NOT: InvokeStaticOrDirect loop:{{B\d+}}
  
    /// CHECK-START: int Main.invariantBoundIntrinsic(int) licm (after)
    /// CHECK-DAG: InvokeStaticOrDirect loop:none
  
    public static int invariantBoundIntrinsic(int x) {
      int result = 0;
      // The intrinsic call to abs used as loop bound is invariant.
      // As a result, the call itself can be moved out of the loop header.
      for (int i = 0; i < Math.abs(x); i++) {
        result += i;
      }
      return result;
    }
  
    /// CHECK-START: int Main.invariantBodyIntrinsic(int, int) licm (before)
    /// CHECK-DAG: InvokeStaticOrDirect loop:{{B\d+}}
  
    /// CHECK-START: int Main.invariantBodyIntrinsic(int, int) licm (after)
    /// CHECK-NOT: InvokeStaticOrDirect loop:{{B\d+}}
  
    /// CHECK-START: int Main.invariantBodyIntrinsic(int, int) licm (after)
    /// CHECK-DAG: InvokeStaticOrDirect loop:none
  
    public static int invariantBodyIntrinsic(int x, int y) {
      int result = 0;
      for (int i = 0; i < 10; i++) {
        // The intrinsic call to max used inside the loop is invariant.
        // As a result, the call itself can be moved out of the loop body.
        result += Math.max(x, y);
      }
      return result;
    }
  
    public static int staticField = 42;
  
    public static void assertEquals(int expected, int actual) {
      if (expected != actual) {
        throw new Error("Expected " + expected + ", got " + actual);
      }
    }
  
    public static void main(String[] args) {
      assertEquals(10, div());
      assertEquals(100, innerDiv());
      assertEquals(18900, innerMul());
      assertEquals(105, divByA(2, 0));
      assertEquals(12, arrayLength(new int[] { 4, 8 }));
      assertEquals(21, divAndIntrinsic(new int[] { 4, -2, 8, -3 }));
      assertEquals(45, invariantBoundIntrinsic(-10));
      assertEquals(30, invariantBodyIntrinsic(2, 3));
    }
  }
  