1 files changed, 94 insertions, 0 deletions
diff --git a/examples/src/main/java/examples/IntModBenchmark.java b/examples/src/main/java/examples/IntModBenchmark.java
new file mode 100644
index 0000000..55a119c
--- /dev/null
+++ b/examples/src/main/java/examples/IntModBenchmark.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2009 Google Inc.
+ *
+ * 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.
+ */
+
+package examples;
+
+import com.google.caliper.Runner;
+import com.google.caliper.SimpleBenchmark;
+
+/**
+ * Measures several candidate implementations for mod().
+ */
+@SuppressWarnings("SameParameterValue")
+public class IntModBenchmark extends SimpleBenchmark {
+  private static final int M = (1 << 16) - 1;
+
+  public int timeConditional(int reps) {
+    int dummy = 5;
+    for (int i = 0; i < reps; i++) {
+      dummy += Integer.MAX_VALUE + conditionalMod(dummy, M);
+    }
+    return dummy;
+  }
+
+  private static int conditionalMod(int a, int m) {
+    int r = a % m;
+    return r < 0 ? r + m : r;
+  }
+
+  public int timeDoubleRemainder(int reps) {
+    int dummy = 5;
+    for (int i = 0; i < reps; i++) {
+      dummy += Integer.MAX_VALUE + doubleRemainderMod(dummy, M);
+    }
+    return dummy;
+  }
+
+  @SuppressWarnings("NumericCastThatLosesPrecision") // result of % by an int must be in int range
+  private static int doubleRemainderMod(int a, int m) {
+    return (int) ((a % m + (long) m) % m);
+  }
+
+  public int timeRightShiftingMod(int reps) {
+    int dummy = 5;
+    for (int i = 0; i < reps; i++) {
+      dummy += Integer.MAX_VALUE + rightShiftingMod(dummy, M);
+    }
+    return dummy;
+  }
+
+  @SuppressWarnings("NumericCastThatLosesPrecision") // must be in int range
+  private static int rightShiftingMod(int a, int m) {
+     long r = a % m;
+     return (int) (r + (r >> 63 & m));
+  }
+
+  public int timeLeftShiftingMod(int reps) {
+    int dummy = 5;
+    for (int i = 0; i < reps; i++) {
+      dummy += Integer.MAX_VALUE + leftShiftingMod(dummy, M);
+    }
+    return dummy;
+  }
+
+  @SuppressWarnings("NumericCastThatLosesPrecision") // result of % by an int must be in int range
+  private static int leftShiftingMod(int a, int m) {
+    return (int) ((a + ((long) m << 32)) % m);
+  }
+
+  public int timeWrongMod(int reps) {
+    int dummy = 5;
+    for (int i = 0; i < reps; i++) {
+      dummy += Integer.MAX_VALUE + dummy % M;
+    }
+    return dummy;
+  }
+
+  // TODO: remove this from all examples when IDE plugins are ready
+  public static void main(String[] args) throws Exception {
+    Runner.main(IntModBenchmark.class, args);
+  }
+}
+\ No newline at end of file