/*
* Copyright (C) 2014 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.
*/
#include "compiler_ir.h"
#include "dataflow_iterator-inl.h"
#include "mir_graph.h"
#include "gtest/gtest.h"
namespace art {
class TopologicalSortOrderTest : public testing::Test {
protected:
struct BBDef {
static constexpr size_t kMaxSuccessors = 4;
static constexpr size_t kMaxPredecessors = 4;
BBType type;
size_t num_successors;
BasicBlockId successors[kMaxPredecessors];
size_t num_predecessors;
BasicBlockId predecessors[kMaxPredecessors];
};
#define DEF_SUCC0() \
0u, { }
#define DEF_SUCC1(s1) \
1u, { s1 }
#define DEF_SUCC2(s1, s2) \
2u, { s1, s2 }
#define DEF_SUCC3(s1, s2, s3) \
3u, { s1, s2, s3 }
#define DEF_SUCC4(s1, s2, s3, s4) \
4u, { s1, s2, s3, s4 }
#define DEF_PRED0() \
0u, { }
#define DEF_PRED1(p1) \
1u, { p1 }
#define DEF_PRED2(p1, p2) \
2u, { p1, p2 }
#define DEF_PRED3(p1, p2, p3) \
3u, { p1, p2, p3 }
#define DEF_PRED4(p1, p2, p3, p4) \
4u, { p1, p2, p3, p4 }
#define DEF_BB(type, succ, pred) \
{ type, succ, pred }
void DoPrepareBasicBlocks(const BBDef* defs, size_t count) {
cu_.mir_graph->block_id_map_.clear();
cu_.mir_graph->block_list_.clear();
ASSERT_LT(3u, count); // null, entry, exit and at least one bytecode block.
ASSERT_EQ(kNullBlock, defs[0].type);
ASSERT_EQ(kEntryBlock, defs[1].type);
ASSERT_EQ(kExitBlock, defs[2].type);
for (size_t i = 0u; i != count; ++i) {
const BBDef* def = &defs[i];
BasicBlock* bb = cu_.mir_graph->CreateNewBB(def->type);
if (def->num_successors <= 2) {
bb->successor_block_list_type = kNotUsed;
bb->fall_through = (def->num_successors >= 1) ? def->successors[0] : 0u;
bb->taken = (def->num_successors >= 2) ? def->successors[1] : 0u;
} else {
bb->successor_block_list_type = kPackedSwitch;
bb->fall_through = 0u;
bb->taken = 0u;
bb->successor_blocks.reserve(def->num_successors);
for (size_t j = 0u; j != def->num_successors; ++j) {
SuccessorBlockInfo* successor_block_info =
static_cast<SuccessorBlockInfo*>(cu_.arena.Alloc(sizeof(SuccessorBlockInfo),
kArenaAllocSuccessor));
successor_block_info->block = j;
successor_block_info->key = 0u; // Not used by class init check elimination.
bb->successor_blocks.push_back(successor_block_info);
}
}
bb->predecessors.assign(def->predecessors, def->predecessors + def->num_predecessors);
if (def->type == kDalvikByteCode || def->type == kEntryBlock || def->type == kExitBlock) {
bb->data_flow_info = static_cast<BasicBlockDataFlow*>(
cu_.arena.Alloc(sizeof(BasicBlockDataFlow), kArenaAllocDFInfo));
}
}
ASSERT_EQ(count, cu_.mir_graph->block_list_.size());
cu_.mir_graph->entry_block_ = cu_.mir_graph->block_list_[1];
ASSERT_EQ(kEntryBlock, cu_.mir_graph->entry_block_->block_type);
cu_.mir_graph->exit_block_ = cu_.mir_graph->block_list_[2];
ASSERT_EQ(kExitBlock, cu_.mir_graph->exit_block_->block_type);
DexFile::CodeItem* code_item = static_cast<DexFile::CodeItem*>(cu_.arena.Alloc(sizeof(DexFile::CodeItem),
kArenaAllocMisc));
cu_.mir_graph->current_code_item_ = code_item;
}
template <size_t count>
void PrepareBasicBlocks(const BBDef (&defs)[count]) {
DoPrepareBasicBlocks(defs, count);
}
void ComputeTopologicalSortOrder() {
cu_.mir_graph->SSATransformationStart();
cu_.mir_graph->ComputeDFSOrders();
cu_.mir_graph->ComputeDominators();
cu_.mir_graph->ComputeTopologicalSortOrder();
cu_.mir_graph->SSATransformationEnd();
ASSERT_FALSE(cu_.mir_graph->topological_order_.empty());
ASSERT_FALSE(cu_.mir_graph->topological_order_loop_ends_.empty());
ASSERT_FALSE(cu_.mir_graph->topological_order_indexes_.empty());
ASSERT_EQ(cu_.mir_graph->GetNumBlocks(), cu_.mir_graph->topological_order_indexes_.size());
for (size_t i = 0, size = cu_.mir_graph->GetTopologicalSortOrder().size(); i != size; ++i) {
ASSERT_LT(cu_.mir_graph->topological_order_[i], cu_.mir_graph->GetNumBlocks());
BasicBlockId id = cu_.mir_graph->topological_order_[i];
EXPECT_EQ(i, cu_.mir_graph->topological_order_indexes_[id]);
}
}
void DoCheckOrder(const BasicBlockId* ids, size_t count) {
ASSERT_EQ(count, cu_.mir_graph->GetTopologicalSortOrder().size());
for (size_t i = 0; i != count; ++i) {
EXPECT_EQ(ids[i], cu_.mir_graph->GetTopologicalSortOrder()[i]) << i;
}
}
template <size_t count>
void CheckOrder(const BasicBlockId (&ids)[count]) {
DoCheckOrder(ids, count);
}
void DoCheckLoopEnds(const uint16_t* ends, size_t count) {
for (size_t i = 0; i != count; ++i) {
ASSERT_LT(i, cu_.mir_graph->GetTopologicalSortOrderLoopEnds().size());
EXPECT_EQ(ends[i], cu_.mir_graph->GetTopologicalSortOrderLoopEnds()[i]) << i;
}
}
template <size_t count>
void CheckLoopEnds(const uint16_t (&ends)[count]) {
DoCheckLoopEnds(ends, count);
}
TopologicalSortOrderTest()
: pool_(),
cu_(&pool_, kRuntimeISA, nullptr, nullptr) {
cu_.mir_graph.reset(new MIRGraph(&cu_, &cu_.arena));
}
ArenaPool pool_;
CompilationUnit cu_;
};
TEST_F(TopologicalSortOrderTest, DoWhile) {
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(5)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(4), DEF_PRED1(1)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(5, 4), DEF_PRED2(3, 4)), // "taken" loops to self.
DEF_BB(kDalvikByteCode, DEF_SUCC1(2), DEF_PRED1(4)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 5, 2
};
const uint16_t loop_ends[] = {
0, 0, 3, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, While) {
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(5)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 5), DEF_PRED2(1, 4)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(3), DEF_PRED1(3)), // Loops to 3.
DEF_BB(kDalvikByteCode, DEF_SUCC1(2), DEF_PRED1(3)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 5, 2
};
const uint16_t loop_ends[] = {
0, 3, 0, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, WhileWithTwoBackEdges) {
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(6)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 6), DEF_PRED3(1, 4, 5)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(5, 3), DEF_PRED1(3)), // Loops to 3.
DEF_BB(kDalvikByteCode, DEF_SUCC1(3), DEF_PRED1(4)), // Loops to 3.
DEF_BB(kDalvikByteCode, DEF_SUCC1(2), DEF_PRED1(3)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 5, 6, 2
};
const uint16_t loop_ends[] = {
0, 4, 0, 0, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, NestedLoop) {
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(7)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 7), DEF_PRED2(1, 6)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(5, 6), DEF_PRED2(3, 5)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(4), DEF_PRED1(4)), // Loops to 4.
DEF_BB(kDalvikByteCode, DEF_SUCC1(3), DEF_PRED1(4)), // Loops to 3.
DEF_BB(kDalvikByteCode, DEF_SUCC1(2), DEF_PRED1(3)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 5, 6, 7, 2
};
const uint16_t loop_ends[] = {
0, 5, 4, 0, 0, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, NestedLoopHeadLoops) {
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(6)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 6), DEF_PRED2(1, 4)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(5, 3), DEF_PRED2(3, 5)), // Nested head, loops to 3.
DEF_BB(kDalvikByteCode, DEF_SUCC1(4), DEF_PRED1(4)), // Loops to 4.
DEF_BB(kDalvikByteCode, DEF_SUCC1(2), DEF_PRED1(3)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 5, 6, 2
};
const uint16_t loop_ends[] = {
0, 4, 4, 0, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, NestedLoopSameBackBranchBlock) {
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(6)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 6), DEF_PRED2(1, 5)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(5), DEF_PRED2(3, 5)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 3), DEF_PRED1(4)), // Loops to 4 and 3.
DEF_BB(kDalvikByteCode, DEF_SUCC1(2), DEF_PRED1(3)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 5, 6, 2
};
const uint16_t loop_ends[] = {
0, 4, 4, 0, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, TwoReorderedInnerLoops) {
// This is a simplified version of real code graph where the branch from 8 to 5 must prevent
// the block 5 from being considered a loop head before processing the loop 7-8.
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(9)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 9), DEF_PRED2(1, 5)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(5, 7), DEF_PRED1(3)), // Branch over loop in 5.
DEF_BB(kDalvikByteCode, DEF_SUCC2(6, 3), DEF_PRED3(4, 6, 8)), // Loops to 4; inner loop.
DEF_BB(kDalvikByteCode, DEF_SUCC1(5), DEF_PRED1(5)), // Loops to 5.
DEF_BB(kDalvikByteCode, DEF_SUCC1(8), DEF_PRED2(4, 8)), // Loop head.
DEF_BB(kDalvikByteCode, DEF_SUCC2(7, 5), DEF_PRED1(7)), // Loops to 7; branches to 5.
DEF_BB(kDalvikByteCode, DEF_SUCC1(2), DEF_PRED1(3)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 7, 8, 5, 6, 9, 2
};
const uint16_t loop_ends[] = {
0, 7, 0, 5, 0, 7, 0, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, NestedLoopWithBackEdgeAfterOuterLoopBackEdge) {
// This is a simplified version of real code graph. The back-edge from 7 to the inner
// loop head 4 comes after the back-edge from 6 to the outer loop head 3. To make this
// appear a bit more complex, there's also a back-edge from 5 to 4.
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(7)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(4), DEF_PRED2(1, 6)), // Outer loop head.
DEF_BB(kDalvikByteCode, DEF_SUCC2(5, 6), DEF_PRED3(3, 5, 7)), // Inner loop head.
DEF_BB(kDalvikByteCode, DEF_SUCC1(4), DEF_PRED1(4)), // Loops to inner loop head 4.
DEF_BB(kDalvikByteCode, DEF_SUCC2(7, 3), DEF_PRED1(4)), // Loops to outer loop head 3.
DEF_BB(kDalvikByteCode, DEF_SUCC2(2, 4), DEF_PRED1(6)), // Loops to inner loop head 4.
};
const BasicBlockId expected_order[] = {
// NOTE: The 5 goes before 6 only because 5 is a "fall-through" from 4 while 6 is "taken".
1, 3, 4, 5, 6, 7, 2
};
const uint16_t loop_ends[] = {
0, 6, 6, 0, 0, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, LoopWithTwoEntryPoints) {
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(7)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(5, 4), DEF_PRED1(1)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(5), DEF_PRED2(3, 6)), // Fall-back block is chosen as
DEF_BB(kDalvikByteCode, DEF_SUCC1(6), DEF_PRED2(3, 4)), // the earlier from these two.
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 7), DEF_PRED1(5)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(2), DEF_PRED1(6)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 5, 6, 7, 2
};
const uint16_t loop_ends[] = {
0, 0, 5, 0, 0, 0, 0
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
}
TEST_F(TopologicalSortOrderTest, UnnaturalLoops) {
const BBDef bbs[] = {
DEF_BB(kNullBlock, DEF_SUCC0(), DEF_PRED0()),
DEF_BB(kEntryBlock, DEF_SUCC1(3), DEF_PRED0()),
DEF_BB(kExitBlock, DEF_SUCC0(), DEF_PRED1(10)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(5, 4), DEF_PRED1(1)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(5), DEF_PRED2(11, 3)), // Unnatural loop head (top-level).
DEF_BB(kDalvikByteCode, DEF_SUCC1(6), DEF_PRED2(3, 4)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(9, 7), DEF_PRED1(5)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(8), DEF_PRED1(6)),
DEF_BB(kDalvikByteCode, DEF_SUCC1(9), DEF_PRED2(10, 7)), // Unnatural loop head (nested).
DEF_BB(kDalvikByteCode, DEF_SUCC1(10), DEF_PRED2(6, 8)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(8, 11), DEF_PRED1(9)),
DEF_BB(kDalvikByteCode, DEF_SUCC2(4, 2), DEF_PRED1(10)),
};
const BasicBlockId expected_order[] = {
1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 2
};
const uint16_t loop_ends[] = {
0, 0, 10, 0, 0, 0, 9, 0, 0, 0, 0,
};
PrepareBasicBlocks(bbs);
ComputeTopologicalSortOrder();
CheckOrder(expected_order);
CheckLoopEnds(loop_ends);
const std::pair<BasicBlockId, bool> expected_and_change[] = {
{ 1, false },
{ 3, false },
{ 4, true }, // Initial run of the outer loop.
{ 5, true },
{ 6, true },
{ 7, true },
{ 8, true }, // Initial run of the inner loop.
{ 9, true },
{ 10, true },
{ 8, true }, // Recalculation of the inner loop - changed.
{ 9, true },
{ 10, true },
{ 8, false }, // Recalculation of the inner loop - unchanged.
{ 11, true },
{ 4, true }, // Recalculation of the outer loop - changed.
{ 5, true },
{ 6, true },
{ 7, false }, // No change: skip inner loop head because inputs are unchanged.
{ 9, true },
{ 10, true },
{ 8, true }, // Recalculation of the inner loop - changed.
{ 9, true },
{ 10, true },
{ 8, false }, // Recalculation of the inner loop - unchanged.
{ 11, true },
{ 4, false }, // Recalculation of the outer loop - unchanged.
{ 2, false },
};
size_t pos = 0;
LoopRepeatingTopologicalSortIterator iter(cu_.mir_graph.get());
bool change = false;
for (BasicBlock* bb = iter.Next(change); bb != nullptr; bb = iter.Next(change)) {
ASSERT_NE(arraysize(expected_and_change), pos);
ASSERT_EQ(expected_and_change[pos].first, bb->id) << pos;
change = expected_and_change[pos].second;
++pos;
}
ASSERT_EQ(arraysize(expected_and_change), pos);
}
} // namespace art