/*
* 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 {
public static void assertIntEquals(int expected, int result) {
if (expected != result) {
throw new Error("Expected: " + expected + ", found: " + result);
}
}
public static boolean inlineTrue() {
return true;
}
public static boolean inlineFalse() {
return false;
}
/// CHECK-START: int Main.testTrueBranch(int, int) dead_code_elimination$after_inlining (before)
/// CHECK-DAG: <<ArgX:i\d+>> ParameterValue
/// CHECK-DAG: <<ArgY:i\d+>> ParameterValue
/// CHECK-DAG: If
/// CHECK-DAG: <<Add:i\d+>> Add [<<ArgX>>,<<ArgY>>]
/// CHECK-DAG: <<Sub:i\d+>> Sub [<<ArgX>>,<<ArgY>>]
/// CHECK-DAG: <<Phi:i\d+>> Phi [<<Add>>,<<Sub>>]
/// CHECK-DAG: Return [<<Phi>>]
/// CHECK-START: int Main.testTrueBranch(int, int) dead_code_elimination$after_inlining (after)
/// CHECK-DAG: <<ArgX:i\d+>> ParameterValue
/// CHECK-DAG: <<ArgY:i\d+>> ParameterValue
/// CHECK-DAG: <<Add:i\d+>> Add [<<ArgX>>,<<ArgY>>]
/// CHECK-DAG: Return [<<Add>>]
/// CHECK-START: int Main.testTrueBranch(int, int) dead_code_elimination$after_inlining (after)
/// CHECK-NOT: If
/// CHECK-NOT: Sub
/// CHECK-NOT: Phi
public static int testTrueBranch(int x, int y) {
int z;
if (inlineTrue()) {
z = x + y;
} else {
z = x - y;
// Prevent HSelect simplification by having a branch with multiple instructions.
System.nanoTime();
}
return z;
}
/// CHECK-START: int Main.testFalseBranch(int, int) dead_code_elimination$after_inlining (before)
/// CHECK-DAG: <<ArgX:i\d+>> ParameterValue
/// CHECK-DAG: <<ArgY:i\d+>> ParameterValue
/// CHECK-DAG: If
/// CHECK-DAG: <<Add:i\d+>> Add [<<ArgX>>,<<ArgY>>]
/// CHECK-DAG: <<Sub:i\d+>> Sub [<<ArgX>>,<<ArgY>>]
/// CHECK-DAG: <<Phi:i\d+>> Phi [<<Add>>,<<Sub>>]
/// CHECK-DAG: Return [<<Phi>>]
/// CHECK-START: int Main.testFalseBranch(int, int) dead_code_elimination$after_inlining (after)
/// CHECK-DAG: <<ArgX:i\d+>> ParameterValue
/// CHECK-DAG: <<ArgY:i\d+>> ParameterValue
/// CHECK-DAG: <<Sub:i\d+>> Sub [<<ArgX>>,<<ArgY>>]
/// CHECK-DAG: Return [<<Sub>>]
/// CHECK-START: int Main.testFalseBranch(int, int) dead_code_elimination$after_inlining (after)
/// CHECK-NOT: If
/// CHECK-NOT: Add
/// CHECK-NOT: Phi
public static int testFalseBranch(int x, int y) {
int z;
if (inlineFalse()) {
z = x + y;
} else {
z = x - y;
// Prevent HSelect simplification by having a branch with multiple instructions.
System.nanoTime();
}
return z;
}
/// CHECK-START: int Main.testRemoveLoop(int) dead_code_elimination$after_inlining (before)
/// CHECK: Mul
/// CHECK-START: int Main.testRemoveLoop(int) dead_code_elimination$after_inlining (after)
/// CHECK-NOT: Mul
public static int testRemoveLoop(int x) {
if (inlineFalse()) {
for (int i = 0; i < x; ++i) {
x *= x;
}
}
return x;
}
/// CHECK-START: int Main.testInfiniteLoop(int) dead_code_elimination$after_inlining (before)
/// CHECK-DAG: Return
/// CHECK-DAG: Exit
/// CHECK-START: int Main.testInfiniteLoop(int) dead_code_elimination$after_inlining (after)
/// CHECK-NOT: Return
/// CHECK-NOT: Exit
public static int testInfiniteLoop(int x) {
while (inlineTrue()) {
x++;
}
return x;
}
/// CHECK-START: int Main.testDeadLoop(int) dead_code_elimination$after_inlining (before)
/// CHECK-DAG: If
/// CHECK-DAG: Add
/// CHECK-START: int Main.testDeadLoop(int) dead_code_elimination$after_inlining (after)
/// CHECK-DAG: <<Arg:i\d+>> ParameterValue
/// CHECK-DAG: Return [<<Arg>>]
/// CHECK-START: int Main.testDeadLoop(int) dead_code_elimination$after_inlining (after)
/// CHECK-NOT: If
/// CHECK-NOT: Add
public static int testDeadLoop(int x) {
while (inlineFalse()) {
x++;
}
return x;
}
/// CHECK-START: int Main.testUpdateLoopInformation(int) dead_code_elimination$after_inlining (before)
/// CHECK-DAG: If
/// CHECK-DAG: If
/// CHECK-DAG: Add
/// CHECK-START: int Main.testUpdateLoopInformation(int) dead_code_elimination$after_inlining (after)
/// CHECK-DAG: <<Arg:i\d+>> ParameterValue
/// CHECK-DAG: Return [<<Arg>>]
/// CHECK-START: int Main.testUpdateLoopInformation(int) dead_code_elimination$after_inlining (after)
/// CHECK-NOT: If
/// CHECK-NOT: Add
public static int testUpdateLoopInformation(int x) {
// Use of Or in the condition generates a dead loop where not all of its
// blocks are removed. This forces DCE to update their loop information.
while (inlineFalse() || !inlineTrue()) {
x++;
}
return x;
}
/// CHECK-START: int Main.testRemoveSuspendCheck(int, int) dead_code_elimination$after_inlining (before)
/// CHECK: SuspendCheck
/// CHECK: SuspendCheck
/// CHECK: SuspendCheck
/// CHECK-NOT: SuspendCheck
/// CHECK-START: int Main.testRemoveSuspendCheck(int, int) dead_code_elimination$after_inlining (after)
/// CHECK: SuspendCheck
/// CHECK: SuspendCheck
/// CHECK-NOT: SuspendCheck
public static int testRemoveSuspendCheck(int x, int y) {
// Inner loop will leave behind the header with its SuspendCheck. DCE must
// remove it, otherwise the outer loop would end up with two.
while (y > 0) {
while (inlineFalse() || !inlineTrue()) {
x++;
}
y--;
}
return x;
}
public static void main(String[] args) {
assertIntEquals(7, testTrueBranch(4, 3));
assertIntEquals(1, testFalseBranch(4, 3));
assertIntEquals(42, testRemoveLoop(42));
assertIntEquals(23, testUpdateLoopInformation(23));
assertIntEquals(12, testRemoveSuspendCheck(12, 5));
}
}