Coverage for /Syzygy/reorder/basic_block_optimizer_unittest.cc

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99.2%2632650.C++test

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   1    :  // Copyright 2012 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  
  15    :  #include "syzygy/reorder/basic_block_optimizer.h"
  16    :  
  17    :  #include "gmock/gmock.h"
  18    :  #include "gtest/gtest.h"
  19    :  #include "syzygy/block_graph/basic_block_test_util.h"
  20    :  #include "syzygy/block_graph/block_graph.h"
  21    :  #include "syzygy/core/unittest_util.h"
  22    :  #include "syzygy/pe/pe_utils.h"
  23    :  #include "syzygy/reorder/order_generator_test.h"
  24    :  
  25    :  #include "mnemonics.h"  // NOLINT
  26    :  
  27    :  namespace reorder {
  28    :  namespace {
  29    :  
  30    :  using block_graph::BasicBlock;
  31    :  using block_graph::BasicCodeBlock;
  32    :  using block_graph::BasicDataBlock;
  33    :  using block_graph::BlockGraph;
  34    :  using core::RelativeAddress;
  35    :  using grinder::basic_block_util::EntryCountType;
  36    :  using grinder::basic_block_util::IndexedFrequencyInformation;
  37    :  using grinder::basic_block_util::IndexedFrequencyMap;
  38    :  using grinder::basic_block_util::LoadBasicBlockRanges;
  39    :  using grinder::basic_block_util::RelativeAddressRange;
  40    :  using grinder::basic_block_util::RelativeAddressRangeVector;
  41    :  using pe::ImageLayout;
  42    :  using testing::GetExeTestDataRelativePath;
  43    :  
  44    :  typedef Reorderer::Order Order;
  45    :  
  46    :  class TestBasicBlockOrderer : public BasicBlockOptimizer::BasicBlockOrderer {
  47    :   public:
  48    :    using BasicBlockOptimizer::BasicBlockOrderer::GetBasicBlockEntryCount;
  49    :    using BasicBlockOptimizer::BasicBlockOrderer::GetWarmestSuccessor;
  50    :    using BasicBlockOptimizer::BasicBlockOrderer::GetSortedJumpTargets;
  51    :    using BasicBlockOptimizer::BasicBlockOrderer::AddRecursiveDataReferences;
  52    :    using BasicBlockOptimizer::BasicBlockOrderer::AddWarmDataReferences;
  53    :  
  54    :    TestBasicBlockOrderer(
  55    :        const BasicBlockSubGraph& subgraph,
  56    :        const RelativeAddress& addr,
  57    :        Size size,
  58    :        const IndexedFrequencyInformation& entry_counts)
  59    :            : BasicBlockOptimizer::BasicBlockOrderer(
  60  E :                  subgraph, addr, size, entry_counts) {
  61  E :    }
  62    :  };
  63    :  
  64    :  class BasicBlockOrdererTest : public testing::BasicBlockTest {
  65    :   public:
  66  E :    virtual void SetUp() override {
  67  E :      ASSERT_NO_FATAL_FAILURE(testing::BasicBlockTest::SetUp());
  68  E :      ASSERT_NO_FATAL_FAILURE(InitBlockGraph());
  69  E :      ASSERT_NO_FATAL_FAILURE(InitBasicBlockSubGraph());
  70  E :      ASSERT_NO_FATAL_FAILURE(SetEntryCounts(0, 0, 0, 0, 0, 0, 0, 0));
  71    :      orderer_.reset(new TestBasicBlockOrderer(subgraph_,
  72    :                                               start_addr_,
  73    :                                               assembly_func_->size(),
  74  E :                                               entry_counts_));
  75  E :      ASSERT_TRUE(orderer_.get() != NULL);
  76  E :    }
  77    :  
  78    :    RelativeAddressRange MakeRange(BlockGraph::Offset offset,
  79    :                                   BlockGraph::Size size) {
  80    :      return RelativeAddressRange(start_addr_ + offset, size);
  81    :    }
  82    :  
  83  E :    BasicBlock* FindBasicBlockAt(BlockGraph::Offset offset) {
  84    :      typedef BasicBlockSubGraph::BBCollection BBCollection;
  85    :      BasicBlockSubGraph::BBCollection::iterator it =
  86  E :          subgraph_.basic_blocks().begin();
  87  E :      for (; it != subgraph_.basic_blocks().end(); ++it) {
  88  E :        if ((*it)->offset() == offset)
  89  E :          return *it;
  90  E :      }
  91  i :      return NULL;
  92  E :    }
  93    :  
  94    :    void SetEntryCounts(uint32 bb0, uint32 bb1, uint32 bb2, uint32 bb3,
  95  E :                        uint32 bb4, uint32 bb5, uint32 bb6, uint32 bb7) {
  96  E :      entry_counts_.num_entries = kNumCodeBasicBlocks;
  97  E :      entry_counts_.num_columns = 1;
  98    :      entry_counts_.data_type =
  99  E :          ::common::IndexedFrequencyData::BASIC_BLOCK_ENTRY;
 100  E :      entry_counts_.frequency_size = 4;
 101    :  
 102  E :      IndexedFrequencyMap& frequency_map = entry_counts_.frequency_map;
 103  E :      frequency_map.clear();
 104    :  
 105  E :      frequency_map[std::make_pair(start_addr_ + kBasicBlockOffsets[0], 0)] = bb0;
 106  E :      frequency_map[std::make_pair(start_addr_ + kBasicBlockOffsets[1], 0)] = bb1;
 107  E :      frequency_map[std::make_pair(start_addr_ + kBasicBlockOffsets[2], 0)] = bb2;
 108  E :      frequency_map[std::make_pair(start_addr_ + kBasicBlockOffsets[3], 0)] = bb3;
 109  E :      frequency_map[std::make_pair(start_addr_ + kBasicBlockOffsets[4], 0)] = bb4;
 110  E :      frequency_map[std::make_pair(start_addr_ + kBasicBlockOffsets[5], 0)] = bb5;
 111  E :      frequency_map[std::make_pair(start_addr_ + kBasicBlockOffsets[6], 0)] = bb6;
 112  E :      frequency_map[std::make_pair(start_addr_ + kBasicBlockOffsets[7], 0)] = bb7;
 113  E :      ASSERT_EQ(kNumCodeBasicBlocks, frequency_map.size());
 114  E :    }
 115    :  
 116    :    static const size_t kBasicBlockOffsets[kNumCodeBasicBlocks];
 117    :  
 118    :    IndexedFrequencyInformation entry_counts_;
 119    :    scoped_ptr<TestBasicBlockOrderer> orderer_;
 120    :  };
 121    :  
 122    :  const size_t BasicBlockOrdererTest::kBasicBlockOffsets[kNumCodeBasicBlocks] =
 123    :      { 0, 23, 24, 31, 36, 37, 42, 49 };
 124    :  
 125    :  class BasicBlockOptimizerTest : public testing::OrderGeneratorTest {
 126    :   public:
 127    :    typedef testing::OrderGeneratorTest Super;
 128    :  
 129    :    BasicBlockOptimizerTest()
 130    :        : num_decomposable_blocks_(0),
 131    :          num_non_decomposable_blocks_(0),
 132  E :          num_non_code_blocks_(0) {
 133  E :    }
 134    :  
 135  E :    virtual void SetUp() override {
 136  E :      ASSERT_NO_FATAL_FAILURE(Super::SetUp());
 137  E :      ASSERT_NO_FATAL_FAILURE(InitBlockCounts());
 138    :      base::FilePath pdb_path(GetExeTestDataRelativePath(
 139  E :          testing::kBBEntryInstrumentedTestDllPdbName));
 140  E :    }
 141    :  
 142  E :    void InitBlockCounts() {
 143  E :      ASSERT_EQ(0U, num_decomposable_blocks_);
 144  E :      ASSERT_EQ(0U, num_non_decomposable_blocks_);
 145  E :      ASSERT_EQ(0U, num_non_code_blocks_);
 146    :  
 147  E :      for (size_t i = 0; i < image_layout_.sections.size(); ++i) {
 148  E :        const ImageLayout::SectionInfo& section_info = image_layout_.sections[i];
 149    :        BlockGraph::AddressSpace::RangeMapConstIterPair ip =
 150    :            image_layout_.blocks.GetIntersectingBlocks(section_info.addr,
 151  E :                                                       section_info.size);
 152  E :        for (; ip.first != ip.second; ++ip.first) {
 153  E :          const BlockGraph::Block* block = ip.first->second;
 154  E :          if (block->type() != BlockGraph::CODE_BLOCK) {
 155  E :            ++num_non_code_blocks_;
 156  E :          } else if (policy_.BlockIsSafeToBasicBlockDecompose(block)) {
 157  E :            ++num_decomposable_blocks_;
 158  E :          } else {
 159  E :            ++num_non_decomposable_blocks_;
 160    :          }
 161  E :        }
 162  E :      }
 163  E :    }
 164    :  
 165    :    bool FindBlockByName(const base::StringPiece& name,
 166    :                         const BlockGraph::Block** block,
 167  E :                         BlockGraph::AddressSpace::Range* range) {
 168  E :      DCHECK(block != NULL);
 169  E :      DCHECK(range != NULL);
 170    :      BlockGraph::AddressSpace::RangeMapConstIter it =
 171  E :          image_layout_.blocks.begin();
 172  E :      for (; it != image_layout_.blocks.end(); ++it) {
 173  E :        if (it->second->name() == name) {
 174  E :          *range = it->first;
 175  E :          *block = it->second;
 176  E :          return true;
 177    :        }
 178  E :      }
 179  i :      return false;
 180  E :    }
 181    :  
 182    :   protected:
 183    :    pe::PETransformPolicy policy_;
 184    :    BasicBlockOptimizer optimizer_;
 185    :    size_t num_decomposable_blocks_;
 186    :    size_t num_non_decomposable_blocks_;
 187    :    size_t num_non_code_blocks_;
 188    :  };
 189    :  
 190    :  }  // namespace
 191    :  
 192  E :  TEST_F(BasicBlockOrdererTest, GetBlockEntryCount) {
 193  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(1, 0, 1, 5, 1, 0, 0, 0));
 194  E :    EntryCountType entry_count = 0;
 195  E :    EXPECT_TRUE(orderer_->GetBlockEntryCount(&entry_count));
 196  E :    EXPECT_EQ(1U, entry_count);
 197    :  
 198  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(17, 0, 1, 5, 1, 0, 0, 0));
 199  E :    EXPECT_TRUE(orderer_->GetBlockEntryCount(&entry_count));
 200  E :    EXPECT_EQ(17U, entry_count);
 201  E :  }
 202    :  
 203  E :  TEST_F(BasicBlockOrdererTest, GetWarmestSuccessor) {
 204  E :    const BasicCodeBlock* sub = BasicCodeBlock::Cast(FindBasicBlockAt(31));
 205  E :    ASSERT_TRUE(sub != NULL);
 206    :  
 207  E :    const BasicCodeBlock* ret = BasicCodeBlock::Cast(FindBasicBlockAt(36));
 208  E :    ASSERT_TRUE(ret != NULL);
 209    :  
 210  E :    TestBasicBlockOrderer::BasicBlockSet placed_bbs;
 211  E :    const BasicBlock* succ = NULL;
 212    :  
 213    :    // Make the fall-through as the warmest successor.
 214  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(0, 0, 0, 5, 10, 0, 0, 0));
 215  E :    ASSERT_TRUE(orderer_->GetWarmestSuccessor(sub, placed_bbs, &succ));
 216  E :    ASSERT_EQ(ret, succ);
 217    :  
 218    :    // Make the branch taken as the warmest successor.
 219  E :    succ = NULL;
 220  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(0, 0, 0, 10, 5, 0, 0, 0));
 221  E :    ASSERT_TRUE(orderer_->GetWarmestSuccessor(sub, placed_bbs, &succ));
 222  E :    ASSERT_EQ(sub, succ);
 223    :  
 224    :    // Give both branches the same warmth. Should preserve ordering.
 225  E :    succ = NULL;
 226  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(0, 0, 0, 10, 10, 0, 0, 0));
 227  E :    ASSERT_TRUE(orderer_->GetWarmestSuccessor(sub, placed_bbs, &succ));
 228  E :    ASSERT_EQ(ret, succ);
 229    :  
 230    :    // Let the warmest branch already be placed, should return the other branch.
 231  E :    succ = NULL;
 232  E :    placed_bbs.insert(ret);
 233  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(0, 0, 0, 5, 10, 0, 0, 0));
 234  E :    ASSERT_TRUE(orderer_->GetWarmestSuccessor(sub, placed_bbs, &succ));
 235  E :    ASSERT_EQ(sub, succ);
 236    :  
 237    :    // Let the warmest branch already be placed, should return the other branch.
 238    :    // Note that we initialize succ to non NULL to verify that it becomes NULL.
 239  E :    succ = sub;
 240  E :    placed_bbs.insert(sub);
 241  E :    placed_bbs.insert(ret);
 242  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(0, 0, 0, 5, 10, 0, 0, 0));
 243  E :    ASSERT_TRUE(orderer_->GetWarmestSuccessor(sub, placed_bbs, &succ));
 244  E :    ASSERT_EQ(NULL, succ);
 245  E :  }
 246    :  
 247  E :  TEST_F(BasicBlockOrdererTest, AddWarmDataReferences) {
 248    :    // Get basic block pointers to the switch, jump table, and case table.
 249  E :    const BasicCodeBlock* code_bb = BasicCodeBlock::Cast(FindBasicBlockAt(0));
 250  E :    const BasicDataBlock* jump_table = BasicDataBlock::Cast(FindBasicBlockAt(52));
 251  E :    const BasicDataBlock* case_table = BasicDataBlock::Cast(FindBasicBlockAt(64));
 252  E :    ASSERT_TRUE(code_bb != NULL);
 253  E :    ASSERT_TRUE(jump_table != NULL);
 254  E :    ASSERT_TRUE(case_table != NULL);
 255    :  
 256    :    // Capture the references from the switch basic block (offset 0).
 257  E :    TestBasicBlockOrderer::BasicBlockSet references;
 258  E :    ASSERT_TRUE(orderer_->AddWarmDataReferences(code_bb, &references));
 259  E :    EXPECT_EQ(2U, references.size());
 260  E :    EXPECT_EQ(1U, references.count(jump_table));
 261  E :    EXPECT_EQ(1U, references.count(case_table));
 262    :  
 263    :    // Capture the references from the case_0 basic block (offset 24).
 264  E :    references.clear();
 265  E :    code_bb = BasicCodeBlock::Cast(FindBasicBlockAt(24));
 266  E :    ASSERT_TRUE(orderer_->AddWarmDataReferences(code_bb, &references));
 267  E :    EXPECT_TRUE(references.empty());
 268  E :  }
 269    :  
 270  E :  TEST_F(BasicBlockOrdererTest, GetSortedJumpTargets) {
 271  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(0, 0, 2, 0, 0, 1, 3, 0));
 272  E :    const BasicCodeBlock* first_bb = BasicCodeBlock::Cast(FindBasicBlockAt(0));
 273  E :    ASSERT_TRUE(first_bb->successors().empty());
 274  E :    ASSERT_TRUE(!first_bb->instructions().empty());
 275  E :    const block_graph::Instruction& jmp_inst = first_bb->instructions().back();
 276  E :    ASSERT_EQ(I_JMP, jmp_inst.representation().opcode);
 277  E :    logging::SetMinLogLevel(-1);
 278  E :    std::vector<const BasicCodeBlock*> targets;
 279  E :    ASSERT_TRUE(orderer_->GetSortedJumpTargets(jmp_inst, &targets));
 280    :    ASSERT_THAT(targets,
 281    :                testing::ElementsAre(
 282    :                    BasicCodeBlock::Cast(FindBasicBlockAt(42)),
 283    :                    BasicCodeBlock::Cast(FindBasicBlockAt(24)),
 284  E :                    BasicCodeBlock::Cast(FindBasicBlockAt(37))));
 285  E :  }
 286    :  
 287  E :  TEST_F(BasicBlockOrdererTest, GetStableSortedJumpTargets) {
 288  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(0, 0, 1, 0, 0, 2, 1, 0));
 289  E :    const BasicCodeBlock* first_bb = BasicCodeBlock::Cast(FindBasicBlockAt(0));
 290  E :    ASSERT_TRUE(first_bb->successors().empty());
 291  E :    ASSERT_TRUE(!first_bb->instructions().empty());
 292  E :    const block_graph::Instruction& jmp_inst = first_bb->instructions().back();
 293  E :    ASSERT_EQ(I_JMP, jmp_inst.representation().opcode);
 294  E :    logging::SetMinLogLevel(-1);
 295  E :    std::vector<const BasicCodeBlock*> targets;
 296  E :    ASSERT_TRUE(orderer_->GetSortedJumpTargets(jmp_inst, &targets));
 297    :    ASSERT_THAT(targets,
 298    :                testing::ElementsAre(
 299    :                    BasicCodeBlock::Cast(FindBasicBlockAt(37)),
 300    :                    BasicCodeBlock::Cast(FindBasicBlockAt(24)),
 301  E :                    BasicCodeBlock::Cast(FindBasicBlockAt(42))));
 302  E :  }
 303    :  
 304  E :  TEST_F(BasicBlockOrdererTest, HotColdSeparation) {
 305  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(1, 0, 1, 5, 1, 0, 0, 0));
 306  E :    Order::OffsetVector warm;
 307  E :    Order::OffsetVector cold;
 308  E :    ASSERT_TRUE(orderer_->GetBasicBlockOrderings(&warm, &cold));
 309    :    // Note that the bb's at 52 and 64 are the jump and case tables, respectively.
 310  E :    EXPECT_THAT(warm, testing::ElementsAre(0, 24, 31, 36, 52, 64));
 311  E :    EXPECT_THAT(cold, testing::ElementsAre(23, 37, 42, 49));
 312  E :  }
 313    :  
 314  E :  TEST_F(BasicBlockOrdererTest, PathStraightening) {
 315    :    // The default control flow of the block we construct isn't very interesting
 316    :    // from a path straightening perspective. So, we modify it here such that the
 317    :    // jnz instruction the end of the basic block at offset 31 branches to case_1
 318    :    // (at offset 37), and then give that basic-block an elevated entry count.
 319  E :    BasicCodeBlock* case_1 = BasicCodeBlock::Cast(FindBasicBlockAt(37));
 320  E :    ASSERT_TRUE(case_1 != NULL);
 321  E :    ASSERT_EQ(1U, case_1->instructions().size());
 322  E :    ASSERT_EQ(I_CALL, case_1->instructions().front().representation().opcode);
 323    :  
 324  E :    BasicCodeBlock* jnz_bb = BasicCodeBlock::Cast(FindBasicBlockAt(31));
 325  E :    ASSERT_TRUE(jnz_bb != NULL);
 326  E :    ASSERT_EQ(1U, jnz_bb->instructions().size());
 327  E :    ASSERT_EQ(I_SUB, jnz_bb->instructions().front().representation().opcode);
 328  E :    ASSERT_EQ(2U, jnz_bb->successors().size());
 329    :    ASSERT_EQ(block_graph::Successor::kConditionNotEqual,
 330  E :              jnz_bb->successors().front().condition());
 331    :    jnz_bb->successors().front().set_reference(
 332  E :        block_graph::BasicBlockReference(BlockGraph::PC_RELATIVE_REF, 1, case_1));
 333    :  
 334    :    // Setup the entry counts such that the jump table stays in the same order
 335    :    // but case 1 is promoted to follow the jnz basic block.
 336  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(1, 0, 10, 5, 1, 7, 0, 0));
 337  E :    Order::OffsetVector warm;
 338  E :    Order::OffsetVector cold;
 339  E :    ASSERT_TRUE(orderer_->GetBasicBlockOrderings(&warm, &cold));
 340    :    // Note that the bb's at 52 and 64 are the jump and case tables, respectively.
 341  E :    EXPECT_THAT(warm, testing::ElementsAre(0, 24, 31, 37, 36, 52, 64));
 342  E :    EXPECT_THAT(cold, testing::ElementsAre(42, 23, 49));
 343  E :  }
 344    :  
 345  E :  TEST_F(BasicBlockOrdererTest, PathStraighteningAcrossJumpTable) {
 346    :    // Setup the entry counts such that case 1 (at offset 37) is promoted to be
 347    :    // the warmest path through the jump table.
 348  E :    ASSERT_NO_FATAL_FAILURE(SetEntryCounts(1, 0, 1, 5, 1, 7, 0, 0));
 349  E :    Order::OffsetVector warm;
 350  E :    Order::OffsetVector cold;
 351  E :    ASSERT_TRUE(orderer_->GetBasicBlockOrderings(&warm, &cold));
 352    :    // Note that the bb's at 52 and 64 are the jump and case tables, respectively.
 353  E :    EXPECT_THAT(warm, testing::ElementsAre(0, 37, 24, 31, 36, 52, 64));
 354  E :    EXPECT_THAT(cold, testing::ElementsAre(42, 23, 49));
 355  E :  }
 356    :  
 357  E :  TEST_F(BasicBlockOptimizerTest, Accessors) {
 358  E :    const std::string kSectionName(".froboz");
 359  E :    EXPECT_TRUE(!optimizer_.cold_section_name().empty());
 360  E :    EXPECT_NE(kSectionName, optimizer_.cold_section_name());
 361  E :    optimizer_.set_cold_section_name(kSectionName);
 362  E :    EXPECT_EQ(kSectionName, optimizer_.cold_section_name());
 363  E :  }
 364    :  
 365  E :  TEST_F(BasicBlockOptimizerTest, EmptyOrderingAllCold) {
 366  E :    Order order;
 367  E :    IndexedFrequencyInformation entry_counts;
 368  E :    entry_counts.num_entries = 0;
 369  E :    entry_counts.num_columns = 1;
 370  E :    entry_counts.data_type = ::common::IndexedFrequencyData::BASIC_BLOCK_ENTRY;
 371  E :    entry_counts.frequency_size = 4;
 372    :  
 373    :    ASSERT_TRUE(
 374  E :        optimizer_.Optimize(image_layout_, entry_counts, &order));
 375    :  
 376  E :    EXPECT_EQ(image_layout_.sections.size() + 1, order.sections.size());
 377  E :    EXPECT_EQ(optimizer_.cold_section_name(), order.sections.back().name);
 378  E :    EXPECT_EQ(Order::SectionSpec::kNewSectionId, order.sections.back().id);
 379  E :    EXPECT_EQ(pe::kCodeCharacteristics, order.sections.back().characteristics);
 380    :  
 381    :    // Count the blocks left in the original sections. This should only include
 382    :    // non-code blocks.
 383  E :    size_t num_non_code_blocks = 0;
 384  E :    for (size_t i = 0; i < image_layout_.sections.size(); ++i) {
 385  E :      for (size_t k = 0; k < order.sections[i].blocks.size(); ++k) {
 386  E :        const BlockGraph::Block* block = order.sections[i].blocks[k].block;
 387  E :        ASSERT_TRUE(block != NULL);
 388  E :        ASSERT_NE(BlockGraph::CODE_BLOCK, block->type());
 389  E :        ++num_non_code_blocks;
 390  E :      }
 391  E :    }
 392    :  
 393    :    // Validate that we have the expected numbers of blocks.
 394  E :    EXPECT_EQ(num_non_code_blocks_, num_non_code_blocks);
 395    :    EXPECT_EQ(num_decomposable_blocks_ + num_non_decomposable_blocks_,
 396  E :              order.sections.back().blocks.size());
 397  E :    for (size_t i = 0; i < order.sections.back().blocks.size(); ++i) {
 398  E :      EXPECT_TRUE(order.sections.back().blocks[i].basic_block_offsets.empty());
 399  E :    }
 400  E :  }
 401    :  
 402  E :  TEST_F(BasicBlockOptimizerTest, HotCold) {
 403    :    // This test does a simple manipulation of the entry counts for DllMain and
 404    :    // validates that some minimum number of its blocks get moved into the cold
 405    :    // section. We defer to the BasicBlockOrdererTest instances above for the
 406    :    // details Hot/Cold and Path Straightening tests.
 407  E :    const BlockGraph::Block* dllmain = NULL;
 408  E :    BlockGraph::AddressSpace::Range range;
 409  E :    ASSERT_TRUE(FindBlockByName("DllMain", &dllmain, &range));
 410  E :    ASSERT_TRUE(dllmain != NULL);
 411    :  
 412    :    using block_graph::BasicBlockSubGraph;
 413    :    using block_graph::BasicBlockDecomposer;
 414    :  
 415  E :    BasicBlockSubGraph subgraph;
 416  E :    BasicBlockDecomposer decomposer(dllmain, &subgraph);
 417  E :    ASSERT_TRUE(decomposer.Decompose());
 418  E :    ASSERT_EQ(1U, subgraph.block_descriptions().size());
 419    :  
 420    :    // Generate an entry count map with a non-zero count for every other BB.
 421  E :    IndexedFrequencyInformation entry_counts;
 422  E :    entry_counts.num_entries = 0;
 423  E :    entry_counts.num_columns = 1;
 424  E :    entry_counts.data_type = ::common::IndexedFrequencyData::BASIC_BLOCK_ENTRY;
 425  E :    entry_counts.frequency_size = 4;
 426  E :    IndexedFrequencyMap& frequency_map = entry_counts.frequency_map;
 427    :  
 428    :    const BasicBlockSubGraph::BlockDescription& desc =
 429  E :        subgraph.block_descriptions().front();
 430    :    BasicBlockSubGraph::BasicBlockOrdering::const_iterator it(
 431  E :        desc.basic_block_order.begin());
 432  E :    size_t num_basic_blocks = desc.basic_block_order.size();
 433  E :    size_t num_hot_blocks = 0;
 434    :  
 435  E :    bool is_hot = true;
 436  E :    BlockGraph::RelativeAddress start_offs = subgraph.original_block()->addr();
 437  E :    for (; it != desc.basic_block_order.end(); ++it) {
 438  E :      if (is_hot && BasicCodeBlock::Cast(*it) != NULL) {
 439  E :        frequency_map[std::make_pair(start_offs + (*it)->offset(), 0)] = 1;
 440  E :        ++num_hot_blocks;
 441    :      }
 442    :  
 443    :      // Toggle hotness for next block.
 444  E :      is_hot = !is_hot;
 445  E :    }
 446    :  
 447    :    // Create an ordering that moves dllmain to a new section.
 448  E :    std::string section_name(".dllmain");
 449  E :    Order order;
 450  E :    order.sections.resize(1);
 451  E :    order.sections[0].id = Order::SectionSpec::kNewSectionId;
 452  E :    order.sections[0].name = section_name;
 453  E :    order.sections[0].characteristics = pe::kCodeCharacteristics;
 454  E :    order.sections[0].blocks.push_back(Order::BlockSpec(dllmain));
 455    :  
 456    :    ASSERT_TRUE(
 457  E :        optimizer_.Optimize(image_layout_, entry_counts, &order));
 458    :  
 459  E :    ASSERT_EQ(image_layout_.sections.size() + 2, order.sections.size());
 460  E :    ASSERT_EQ(section_name, order.sections[0].name);
 461  E :    ASSERT_EQ(1U, order.sections[0].blocks.size());
 462  E :    ASSERT_TRUE(!order.sections.back().blocks.empty());
 463  E :    ASSERT_EQ(dllmain, order.sections[0].blocks[0].block);
 464  E :    ASSERT_EQ(dllmain, order.sections.back().blocks[0].block);
 465    :    ASSERT_LE(num_hot_blocks,
 466  E :              order.sections[0].blocks[0].basic_block_offsets.size());
 467    :  
 468    :    // Since data BBs that are referred to by 'hot' code BBs also make
 469    :    // it into the hot BB list, there could be fewer cold blocks than expected.
 470    :    ASSERT_GE(num_basic_blocks - num_hot_blocks,
 471  E :              order.sections.back().blocks[0].basic_block_offsets.size());
 472  E :  }
 473    :  
 474    :  }  // namespace reorder

Coverage information generated Thu Jan 14 17:40:38 2016.