/*

 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * @test

 * @bug 8073480

 * @summary explicit range checks should be recognized by C2

 * @library /test/lib /

 * @modules java.base/jdk.internal.misc:+open

 * @build sun.hotspot.WhiteBox

 * @run driver ClassFileInstaller sun.hotspot.WhiteBox

 * @run main/othervm -ea -Xmixed -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI

 *                   -XX:-BackgroundCompilation -XX:-UseOnStackReplacement

 *                   -XX:CompileCommand=compileonly,compiler.rangechecks.TestExplicitRangeChecks::test*

 *                   compiler.rangechecks.TestExplicitRangeChecks

 *

 */

package compiler.rangechecks;

import compiler.whitebox.CompilerWhiteBoxTest;

import jdk.internal.misc.Unsafe;

import jdk.test.lib.Platform;

import sun.hotspot.WhiteBox;

import java.lang.annotation.Retention;

import java.lang.annotation.RetentionPolicy;

import java.lang.reflect.Field;

import java.lang.reflect.Method;

import java.lang.reflect.Modifier;

import java.util.HashMap;

public class TestExplicitRangeChecks {

    private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox();

    private static final int TIERED_STOP_AT_LEVEL = WHITE_BOX.getIntxVMFlag("TieredStopAtLevel").intValue();

    private static int[] array = new int[10];

    private static boolean success = true;

    @Retention(RetentionPolicy.RUNTIME)

    @interface Args {

        int[] compile();

        int[] good();

        int[] bad();

        boolean deoptimize() default true;

    }

    // Should be compiled as a single unsigned comparison

    // 0 <= index < array.length

    @Args(compile = {5,}, good = {0, 9}, bad = {-1, 10})

    static boolean test1_1(int index, int[] array) {

        if (index < 0 || index >= array.length) {

            return false;

        }

        return true;

    }

    // same test but so we can compile with same optimization after trap in test1_1

    static boolean test1_2(int index, int[] array) {

        if (index < 0 || index >= array.length) {

            return false;

        }

        return true;

    }

    // Shouldn't matter whether first or second test is the one

    // against a constants

    // 0 <= index < array.length

    @Args(compile = {5,}, good = {0, 9}, bad = {-1, 10})

    static boolean test2_1(int index, int[] array) {

        if (index >= array.length || index < 0) {

            return false;

        }

        return true;

    }

    static boolean test2_2(int index, int[] array) {

        if (index >= array.length || index < 0) {

            return false;

        }

        return true;

    }

    // 0 <= index <= array.length

    @Args(compile = {5,}, good = {0, 10}, bad = {-1, 11})

    static boolean test3_1(int index, int[] array) {

        if (index < 0 || index > array.length) {

            return false;

        }

        return true;

    }

    static boolean test3_2(int index, int[] array) {

        if (index < 0 || index > array.length) {

            return false;

        }

        return true;

    }

    // 0 <= index <= array.length

    @Args(compile = {5,}, good = {0, 10}, bad = {-1, 11})

    static boolean test4_1(int index, int[] array) {

        if (index > array.length || index < 0 ) {

            return false;

        }

        return true;

    }

    static boolean test4_2(int index, int[] array) {

        if (index > array.length || index < 0) {

            return false;

        }

        return true;

    }

    static int[] test5_helper(int i) {

        return (i < 100) ? new int[10] : new int[5];

    }

    // 0 < index < array.length

    @Args(compile = {5,}, good = {1, 9}, bad = {0, 10})

    static boolean test5_1(int index, int[] array) {

        array = test5_helper(index); // array.length must be not constant greater than 1

        if (index <= 0 || index >= array.length) {

            return false;

        }

        return true;

    }

    static boolean test5_2(int index, int[] array) {

        array = test5_helper(index); // array.length must be not constant greater than 1

        if (index <= 0 || index >= array.length) {

            return false;

        }

        return true;

    }

    // 0 < index < array.length

    @Args(compile = {5,}, good = {1, 9}, bad = {0, 10})

    static boolean test6_1(int index, int[] array) {

        array = test5_helper(index); // array.length must be not constant greater than 1

        if (index >= array.length || index <= 0 ) {

            return false;

        }

        return true;

    }

    static boolean test6_2(int index, int[] array) {

        array = test5_helper(index); // array.length must be not constant greater than 1

        if (index >= array.length || index <= 0) {

            return false;

        }

        return true;

    }

    // 0 < index <= array.length

    @Args(compile = {5,}, good = {1, 10}, bad = {0, 11})

    static boolean test7_1(int index, int[] array) {

        if (index <= 0 || index > array.length) {

            return false;

        }

        return true;

    }

    static boolean test7_2(int index, int[] array) {

        if (index <= 0 || index > array.length) {

            return false;

        }

        return true;

    }

    // 0 < index <= array.length

    @Args(compile = {5,}, good = {1, 10}, bad = {0, 11})

    static boolean test8_1(int index, int[] array) {

        if (index > array.length || index <= 0 ) {

            return false;

        }

        return true;

    }

    static boolean test8_2(int index, int[] array) {

        if (index > array.length || index <= 0) {

            return false;

        }

        return true;

    }

    static int[] test9_helper1(int i) {

        return (i < 100) ? new int[1] : new int[2];

    }

    static int[] test9_helper2(int i) {

        return (i < 100) ? new int[10] : new int[11];

    }

    // array1.length <= index < array2.length

    @Args(compile = {5,}, good = {1, 9}, bad = {0, 10})

    static boolean test9_1(int index, int[] array) {

        int[] array1 = test9_helper1(index);

        int[] array2 = test9_helper2(index);

        if (index < array1.length || index >= array2.length) {

            return false;

        }

        return true;

    }

    static boolean test9_2(int index, int[] array) {

        int[] array1 = test9_helper1(index);

        int[] array2 = test9_helper2(index);

        if (index < array1.length || index >= array2.length) {

            return false;

        }

        return true;

    }

    // Previously supported pattern

    @Args(compile = {-5,5,15}, good = {0, 9}, bad = {-1, 10}, deoptimize=false)

    static boolean test10_1(int index, int[] array) {

        if (index < 0 || index >= 10) {

            return false;

        }

        return true;

    }

    static int[] array11 = new int[10];

    @Args(compile = {5,}, good = {0, 9}, bad = {-1,})

    static boolean test11_1(int index, int[] array) {

        if (index < 0) {

            return false;

        }

        int unused = array11[index];

        // If this one is folded with the first test then we allow

        // array access above to proceed even for out of bound array

        // index and the method throws an

        // ArrayIndexOutOfBoundsException.

        if (index >= array.length) {

            return false;

        }

        return true;

    }

    static int[] array12 = {10, 10, 10, 10, 10, 10, 10, 10, 10, 10};

    @Args(compile = {5,}, good = {0, 9}, bad = {-1,})

    static boolean test12_1(int index, int[] array) {

        // Cannot be folded otherwise would cause incorrect array

        // access if the array12 range check is executed before the

        // folded test.

        if (index < 0 || index >= array12[index]) {

            return false;

        }

        return true;

    }

    // Same as test1_1 but pass null array when index < 0: shouldn't

    // cause NPE.

    @Args(compile = {5,}, good = {0, 9}, bad = {})

    static boolean test13_1(int index, int[] array) {

        if (index < 0 || index >= array.length) {

            return false;

        }

        return true;

    }

    // Same as test10 but with uncommon traps

    @Args(compile = {5}, good = {0, 9}, bad = {-1, 10})

    static boolean test14_1(int index, int[] array) {

        if (index < 0 || index >= 10) {

            return false;

        }

        return true;

    }

    static boolean test14_2(int index, int[] array) {

        if (index < 0 || index >= 10) {

            return false;

        }

        return true;

    }

    // Same as test13_1 but pass null array: null trap should be reported on first if

    @Args(compile = {5,}, good = {0, 9}, bad = {})

    static boolean test15_1(int index, int[] array) {

        if (index < 0 || index >= array.length) {

            return false;

        }

        return true;

    }

    // Same as test1 but with no null check between the integer comparisons

    @Args(compile = {5,}, good = {0, 9}, bad = {-1, 10})

    static boolean test16_1(int index, int[] array) {

        int l = array.length;

        if (index < 0 || index >= l) {

            return false;

        }

        return true;

    }

    static boolean test16_2(int index, int[] array) {

        int l = array.length;

        if (index < 0 || index >= l) {

            return false;

        }

        return true;

    }

    // Same as test1 but bound check on array access should optimize

    // out.

    @Args(compile = {5,}, good = {0, 9}, bad = {-1, 10})

    static boolean test17_1(int index, int[] array) {

        if (index < 0 || index >= array.length) {

            return false;

        }

        array[index] = 0;

        return true;

    }

    static boolean test17_2(int index, int[] array) {

        if (index < 0 || index >= array.length) {

            return false;

        }

        array[index] = 0;

        return true;

    }

    // Same as test1 but range check smearing should optimize

    // 3rd range check out.

    @Args(compile = {5,}, good = {}, bad = {})

    static boolean test18_1(int index, int[] array) {

        if (index < 0 || index >= array.length) {

            return false;

        }

        array[index+2] = 0;

        array[index+1] = 0;

        return true;

    }

    static boolean test19_helper1(int index) {

        if (index < 12) {

            return false;

        }

        return true;

    }

    static boolean test19_helper2(int index) {

        if (index > 8) {

            return false;

        }

        return true;

    }

    // Second test should be optimized out

    static boolean test19(int index, int[] array) {

        test19_helper1(index);

        test19_helper2(index);

        return true;

    }

    final HashMap<String,Method> tests = new HashMap<>();

    {

        for (Method m : this.getClass().getDeclaredMethods()) {

            if (m.getName().matches("test[0-9]+(_[0-9])?")) {

                assert(Modifier.isStatic(m.getModifiers())) : m;

                tests.put(m.getName(), m);

            }

        }

    }

    void doTest(String name) throws Exception {

        Method m = tests.get(name + "_1");

        Args anno =  m.getAnnotation(Args.class);

        int[] compile = anno.compile();

        int[] good = anno.good();

        int[] bad = anno.bad();

        boolean deoptimize = anno.deoptimize();

        // Get compiled

        for (int i = 0; i < 20000;) {

            for (int j = 0; j < compile.length; j++) {

                m.invoke(null, compile[j], array);

                i++;

            }

        }

        if (!WHITE_BOX.isMethodCompiled(m)) {

            System.out.println(name + "_1 not compiled");

            success = false;

        }

        // check that good values don't trigger exception or

        // deoptimization

        for (int i = 0; i < good.length; i++) {

            boolean res = (boolean)m.invoke(null, good[i], array);

            if (!res) {

                System.out.println(name + " bad result for good input " + good[i]);

                success = false;

            }

            if (!WHITE_BOX.isMethodCompiled(m)) {

                System.out.println(name + " deoptimized on valid access");

                success = false;

            }

        }

        // check that bad values trigger exception and deoptimization

        for (int i = 0; i < bad.length; i++) {

            if (i > 0 && deoptimize) {

                m = tests.get(name + "_" + (i+1));

                for (int k = 0; k < 20000;) {

                    for (int j = 0; j < compile.length; j++) {

                        m.invoke(null, compile[j], array);

                        k++;

                    }

                }

                if (!WHITE_BOX.isMethodCompiled(m)) {

                    System.out.println(name + ("_" + (i+1)) + " not compiled");

                    success = false;

                }

            }

            boolean res = (boolean)m.invoke(null, bad[i], array);

            if (res) {

                System.out.println(name + " bad result for bad input " + bad[i]);

                success = false;

            }

            // Only perform these additional checks if C2 is available

            if (Platform.isServer() && !Platform.isEmulatedClient() &&

                TIERED_STOP_AT_LEVEL == CompilerWhiteBoxTest.COMP_LEVEL_FULL_OPTIMIZATION) {

                if (deoptimize && WHITE_BOX.isMethodCompiled(m)) {

                    System.out.println(name + " not deoptimized on invalid access");

                    success = false;

                } else if (!deoptimize && !WHITE_BOX.isMethodCompiled(m)) {

                    System.out.println(name + " deoptimized on invalid access");

                    success = false;

                }

            }

        }

    }

    private static final Unsafe UNSAFE;

    static {

        try {

            Field unsafeField = Unsafe.class.getDeclaredField("theUnsafe");

            unsafeField.setAccessible(true);

            UNSAFE = (Unsafe) unsafeField.get(null);

        }

        catch (Exception e) {

            throw new AssertionError(e);

        }

    }

    // On x64, int to long conversion should optimize away in address computation

    static int test20(int[] a) {

        int sum = 0;

        for (int i = 0; i < a.length; i++) {

            sum += test20_helper(a, i);

        }

        return sum;

    }

    static int test20_helper(int[] a, int i) {

        if (i < 0 || i >= a.length)

            throw new ArrayIndexOutOfBoundsException();

        long address = (((long) i) << 2) + UNSAFE.ARRAY_INT_BASE_OFFSET;

        return UNSAFE.getInt(a, address);

    }

    static int test21(int[] a) {

        int sum = 0;

        for (int i = 0; i < a.length; i++) {

            sum += test20_helper(a, i);

        }

        return sum;

    }

    static int test21_helper(int[] a, int i) {

        if (i < 0 || i >= a.length)

            throw new ArrayIndexOutOfBoundsException();

        long address = (((long) i) << 2) + UNSAFE.ARRAY_INT_BASE_OFFSET;

        return UNSAFE.getIntVolatile(a, address);

    }

    static public void main(String[] args) throws Exception {

        if (WHITE_BOX.getBooleanVMFlag("BackgroundCompilation")) {

            throw new AssertionError("Background compilation enabled");

        }

        TestExplicitRangeChecks test = new TestExplicitRangeChecks();

        test.doTest("test1");

        test.doTest("test2");

        test.doTest("test3");

        test.doTest("test4");

        // pollute branch profile

        for (int i = 0; i < 10000; i++) {

            test5_helper((i%2 == 0) ? 0 : 1000);

        }

        test.doTest("test5");