8169039: Add unit tests for BitMap search operations
authorkbarrett
Wed, 03 May 2017 18:44:27 -0400
changeset 46429 be60dbbce2ec
parent 46428 d577822ca75c
child 46430 45fd2f759802
child 46431 87b0d1afe03e
8169039: Add unit tests for BitMap search operations Summary: Added native unit test test_bitMap_search.cpp Reviewed-by: stefank, sjohanss
hotspot/test/native/utilities/test_bitMap_search.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/native/utilities/test_bitMap_search.cpp	Wed May 03 18:44:27 2017 -0400
@@ -0,0 +1,258 @@
+/*
+ * Copyright (c) 2017, 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.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "utilities/bitMap.inline.hpp"
+#include "utilities/debug.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "unittest.hpp"
+
+typedef BitMap::idx_t idx_t;
+typedef BitMap::bm_word_t bm_word_t;
+
+static const idx_t BITMAP_SIZE = 1024;
+
+static const size_t search_chunk_size = 64;
+
+// Entries must be monotonically increasing.
+// Maximum entry must be < search_chunk_size.
+// Cluster values around possible word-size boundaries.
+static const size_t search_offsets[] =
+  { 0, 1, 2, 29, 30, 31, 32, 33, 34, 60, 62, 63 };
+
+static const size_t search_noffsets = ARRAY_SIZE(search_offsets);
+
+static const size_t search_nchunks = BITMAP_SIZE / search_chunk_size;
+STATIC_ASSERT(search_nchunks * search_chunk_size == BITMAP_SIZE);
+
+namespace {
+class TestIteratorFn : public BitMapClosure {
+public:
+  TestIteratorFn(size_t start, size_t end, size_t left, size_t right);
+  virtual bool do_bit(size_t offset);
+
+private:
+  size_t _entries[2];
+  size_t _index;
+  size_t _count;
+  size_t _start;
+  size_t _end;
+  size_t _left;
+  size_t _right;
+
+  void do_bit_aux(size_t offset);
+
+};
+} // anonymous namespace
+
+TestIteratorFn::TestIteratorFn(size_t start, size_t end,
+                               size_t left, size_t right) :
+  _index(0), _count(0), _start(start), _end(end), _left(left), _right(right)
+{
+  if ((_start <= _left) && (_left < _end)) {
+    _entries[_count++] = _left;
+  }
+  if ((_start <= _right) && (_right < _end)) {
+    _entries[_count++] = _right;
+  }
+}
+
+void TestIteratorFn::do_bit_aux(size_t offset) {
+  EXPECT_LT(_index, _count);
+  if (_index < _count) {
+    EXPECT_EQ(_entries[_index], offset);
+    _index += 1;
+  }
+}
+
+bool TestIteratorFn::do_bit(size_t offset) {
+  do_bit_aux(offset);
+  return true;
+}
+
+static idx_t compute_expected(idx_t search_start,
+                              idx_t search_end,
+                              idx_t left_bit,
+                              idx_t right_bit) {
+  idx_t expected = search_end;
+  if (search_start <= left_bit) {
+    if (left_bit < search_end) {
+      expected = left_bit;
+    }
+  } else if (search_start <= right_bit) {
+    if (right_bit < search_end) {
+      expected = right_bit;
+    }
+  }
+  return expected;
+}
+
+static void test_search_ranges(BitMap& test_ones,
+                               BitMap& test_zeros,
+                               idx_t left,
+                               idx_t right) {
+  // Test get_next_one_offset with full range of map.
+  EXPECT_EQ(left, test_ones.get_next_one_offset(0));
+  EXPECT_EQ(right, test_ones.get_next_one_offset(left + 1));
+  EXPECT_EQ(BITMAP_SIZE, test_ones.get_next_one_offset(right + 1));
+
+  // Test get_next_one_offset_aligned_right with full range of map.
+  EXPECT_EQ(left, test_ones.get_next_one_offset_aligned_right(0, BITMAP_SIZE));
+  EXPECT_EQ(right, test_ones.get_next_one_offset_aligned_right(left + 1, BITMAP_SIZE));
+  EXPECT_EQ(BITMAP_SIZE, test_ones.get_next_one_offset_aligned_right(right + 1, BITMAP_SIZE));
+
+  // Test get_next_zero_offset with full range of map.
+  EXPECT_EQ(left, test_zeros.get_next_zero_offset(0));
+  EXPECT_EQ(right, test_zeros.get_next_zero_offset(left + 1));
+  EXPECT_EQ(BITMAP_SIZE, test_zeros.get_next_zero_offset(right + 1));
+
+  // Check that iterate invokes the closure function on left and right values.
+  TestIteratorFn test_iteration(0, BITMAP_SIZE, left, right);
+  test_ones.iterate(&test_iteration, 0, BITMAP_SIZE);
+
+  // Test searches with various start and end ranges.
+  for (size_t c_start = 0; c_start < search_nchunks; ++c_start) {
+    for (size_t o_start = 0; o_start < search_noffsets; ++o_start) {
+      idx_t start = c_start * search_chunk_size + search_offsets[o_start];
+      // Terminate start iteration if start is more than two full
+      // chunks beyond left.  There isn't anything new to learn by
+      // continuing the iteration, and this noticably reduces the
+      // time to run the test.
+      if (left + 2 * search_chunk_size < start) {
+        c_start = search_nchunks; // Set to limit to terminate iteration.
+        break;
+      }
+
+      for (size_t c_end = c_start; c_end < search_nchunks; ++c_end) {
+        for (size_t o_end = (c_start == c_end) ? o_start : 0;
+             o_end < search_noffsets;
+             ++o_end) {
+          idx_t end = c_end * search_chunk_size + search_offsets[o_end];
+          // Similarly to start and left, terminate end iteration if
+          // end is more than two full chunks beyond right.
+          if (right + 2 * search_chunk_size < end) {
+            c_end = search_nchunks; // Set to limit to terminate iteration.
+            break;
+          }
+          // Skip this chunk if right is much larger than max(left, start)
+          // and this chunk is one of many similar chunks in between,
+          // again to reduce testing time.
+          if (MAX2(start, left) + 2 * search_chunk_size < end) {
+            if (end + 2 * search_chunk_size < right) {
+              break;
+            }
+          }
+
+          bool aligned_right = search_offsets[o_end] == 0;
+          ASSERT_LE(start, end);       // test bug if fail
+          ASSERT_LT(end, BITMAP_SIZE); // test bug if fail
+
+          idx_t expected = compute_expected(start, end, left, right);
+
+          EXPECT_EQ(expected, test_ones.get_next_one_offset(start, end));
+          EXPECT_EQ(expected, test_zeros.get_next_zero_offset(start, end));
+          if (aligned_right) {
+            EXPECT_EQ(
+              expected,
+              test_ones.get_next_one_offset_aligned_right(start, end));
+          }
+
+          idx_t start2 = MIN2(expected + 1, end);
+          idx_t expected2 = compute_expected(start2, end, left, right);
+
+          EXPECT_EQ(expected2, test_ones.get_next_one_offset(start2, end));
+          EXPECT_EQ(expected2, test_zeros.get_next_zero_offset(start2, end));
+          if (aligned_right) {
+            EXPECT_EQ(
+              expected2,
+              test_ones.get_next_one_offset_aligned_right(start2, end));
+          }
+        }
+      }
+    }
+  }
+}
+
+TEST(BitMap, search) {
+  CHeapBitMap test_ones(BITMAP_SIZE);
+  CHeapBitMap test_zeros(BITMAP_SIZE);
+
+  // test_ones is used to test searching for 1s in a region of 0s.
+  // test_zeros is used to test searching for 0s in a region of 1s.
+  test_ones.clear_range(0, test_ones.size());
+  test_zeros.set_range(0, test_zeros.size());
+
+  // Searching "empty" sequence should return size.
+  EXPECT_EQ(BITMAP_SIZE, test_ones.get_next_one_offset(0));
+  EXPECT_EQ(BITMAP_SIZE, test_zeros.get_next_zero_offset(0));
+
+  // With left being in the first or second chunk...
+  for (size_t c_left = 0; c_left < 2; ++c_left) {
+    // Right bit is in the same chunk as left, or next chunk, or far away...
+    for (size_t c_right = c_left;
+         c_right < search_nchunks;
+         (c_right == c_left + 1) ? c_right = search_nchunks - 1 : ++c_right) {
+      // For each offset within the left chunk...
+      for (size_t o_left = 0; o_left < search_noffsets; ++o_left) {
+        // left is start of left chunk + offset.
+        idx_t left = c_left * search_chunk_size + search_offsets[o_left];
+
+        // Install the left bit.
+        test_ones.set_bit(left);
+        test_zeros.clear_bit(left);
+        EXPECT_TRUE(test_ones.at(left));
+        EXPECT_FALSE(test_zeros.at(left));
+
+        // For each offset within the right chunk and > left...
+        for (size_t o_right = (c_left == c_right) ? o_left + 1 : 0;
+             o_right < search_noffsets;
+             ++o_right) {
+          // right is start of right chunk + offset.
+          idx_t right = c_right * search_chunk_size + search_offsets[o_right];
+
+          // Install the right bit.
+          test_ones.set_bit(right);
+          test_zeros.clear_bit(right);
+          EXPECT_TRUE(test_ones.at(right));
+          EXPECT_FALSE(test_zeros.at(right));
+
+          // Apply the test.
+          test_search_ranges(test_ones, test_zeros, left, right);
+
+          // Remove the right bit.
+          test_ones.clear_bit(right);
+          test_zeros.set_bit(right);
+          EXPECT_FALSE(test_ones.at(right));
+          EXPECT_TRUE(test_zeros.at(right));
+        }
+
+        // Remove the left bit.
+        test_ones.clear_bit(left);
+        test_zeros.set_bit(left);
+        EXPECT_FALSE(test_ones.at(left));
+        EXPECT_TRUE(test_zeros.at(left));
+      }
+    }
+  }
+}