Add the code.google.com/p/dalvik benchmarks to libcore.

I'll remove them from code.google.com afterwards.

Change-Id: I369a301ed0e116c7971caebc607c5a86d06d4ee2

1 files changed, 139 insertions, 0 deletions

diff --git a/benchmarks/regression/IntegerBenchmark.java b/benchmarks/regression/IntegerBenchmark.java
new file mode 100644
index 0000000..601bb5d
--- /dev/null
+++ b/benchmarks/regression/IntegerBenchmark.java
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2011 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 benchmarks.regression;
+
+import com.google.caliper.Param;
+import com.google.caliper.SimpleBenchmark;
+
+public class IntegerBenchmark extends SimpleBenchmark {
+    public int timeLongSignumBranch(int reps) {
+        int t = 0;
+        for (int i = 0; i < reps; ++i) {
+            t += signum1(-i);
+            t += signum1(0);
+            t += signum1(i);
+        }
+        return t;
+    }
+
+    public int timeLongSignumBranchFree(int reps) {
+        int t = 0;
+        for (int i = 0; i < reps; ++i) {
+            t += signum2(-i);
+            t += signum2(0);
+            t += signum2(i);
+        }
+        return t;
+    }
+
+    private static int signum1(long v) {
+        return v < 0 ? -1 : (v == 0 ? 0 : 1);
+    }
+
+    private static int signum2(long v) {
+        return ((int)(v >> 63)) | (int) (-v >>> 63); // Hacker's delight 2-7
+    }
+
+    public int timeLongBitCount_BitSet(int reps) {
+        int t = 0;
+        for (int i = 0; i < reps; ++i) {
+            t += pop((long) i);
+        }
+        return t;
+    }
+
+    private static int pop(long l) {
+        int count = popX(l & 0xffffffffL);
+        count += popX(l >>> 32);
+        return count;
+    }
+
+    private static int popX(long x) {
+        // BEGIN android-note
+        // delegate to Integer.bitCount(i); consider using native code
+        // END android-note
+        x = x - ((x >>> 1) & 0x55555555);
+        x = (x & 0x33333333) + ((x >>> 2) & 0x33333333);
+        x = (x + (x >>> 4)) & 0x0f0f0f0f;
+        x = x + (x >>> 8);
+        x = x + (x >>> 16);
+        return (int) x & 0x0000003f;
+    }
+
+    public int timeLongBitCount_2Int(int reps) {
+        int t = 0;
+        for (int i = 0; i < reps; ++i) {
+            t += pop2((long) i);
+        }
+        return t;
+    }
+
+    private static int pop2(long l) {
+        int count = Integer.bitCount((int) (l & 0xffffffffL));
+        count += Integer.bitCount((int) (l >>> 32));
+        return count;
+    }
+
+    public int timeLongBitCount_Long(int reps) {
+        int t = 0;
+        for (int i = 0; i < reps; ++i) {
+            t += Long.bitCount((long) i);
+        }
+        return t;
+    }
+
+    /**
+     * Table for Seal's algorithm for Number of Trailing Zeros. Hacker's Delight
+     * online, Figure 5-18 (http://www.hackersdelight.org/revisions.pdf)
+     * The entries whose value is -1 are never referenced.
+     */
+    private static final byte[] NTZ_TABLE = {
+        32,  0,  1, 12,  2,  6, -1, 13,   3, -1,  7, -1, -1, -1, -1, 14,
+        10,  4, -1, -1,  8, -1, -1, 25,  -1, -1, -1, -1, -1, 21, 27, 15,
+        31, 11,  5, -1, -1, -1, -1, -1,   9, -1, -1, 24, -1, -1, 20, 26,
+        30, -1, -1, -1, -1, 23, -1, 19,  29, -1, 22, 18, 28, 17, 16, -1
+    };
+
+    private static int numberOfTrailingZerosHD(int i) {
+        // Seal's algorithm - Hacker's Delight 5-18
+        i &= -i;
+        i = (i <<  4) + i;    // x *= 17
+        i = (i <<  6) + i;    // x *= 65
+        i = (i << 16) - i;    // x *= 65535
+        return NTZ_TABLE[i >>> 26];
+    }
+
+    private static int numberOfTrailingZerosOL(int i) {
+        return NTZ_TABLE[((i & -i) * 0x0450FBAF) >>> 26];
+    }
+
+    public int timeNumberOfTrailingZerosHD(int reps) {
+        int t = 0;
+        for (int i = 0; i < reps; ++i) {
+            t += numberOfTrailingZerosHD(i);
+        }
+        return t;
+    }
+
+    public int timeNumberOfTrailingZerosOL(int reps) {
+        int t = 0;
+        for (int i = 0; i < reps; ++i) {
+            t += numberOfTrailingZerosOL(i);
+        }
+        return t;
+    }
+}