/*
* 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 "base/arena_allocator.h"
#include "builder.h"
#include "code_generator.h"
#include "dex/dex_file.h"
#include "dex/dex_instruction.h"
#include "driver/compiler_options.h"
#include "nodes.h"
#include "optimizing_unit_test.h"
#include "prepare_for_register_allocation.h"
#include "ssa_liveness_analysis.h"
namespace art {
class LiveRangesTest : public OptimizingUnitTest {
public:
HGraph* BuildGraph(const std::vector<uint16_t>& data);
};
HGraph* LiveRangesTest::BuildGraph(const std::vector<uint16_t>& data) {
HGraph* graph = CreateCFG(data);
// Suspend checks implementation may change in the future, and this test relies
// on how instructions are ordered.
RemoveSuspendChecks(graph);
// `Inline` conditions into ifs.
PrepareForRegisterAllocation(graph, *compiler_options_).Run();
return graph;
}
TEST_F(LiveRangesTest, CFG1) {
/*
* Test the following snippet:
* return 0;
*
* Which becomes the following graph (numbered by lifetime position):
* 2: constant0
* 4: goto
* |
* 8: return
* |
* 12: exit
*/
const std::vector<uint16_t> data = ONE_REGISTER_CODE_ITEM(
Instruction::CONST_4 | 0 | 0,
Instruction::RETURN);
HGraph* graph = BuildGraph(data);
std::unique_ptr<CodeGenerator> codegen = CodeGenerator::Create(graph, *compiler_options_);
SsaLivenessAnalysis liveness(graph, codegen.get(), GetScopedAllocator());
liveness.Analyze();
LiveInterval* interval = liveness.GetInstructionFromSsaIndex(0)->GetLiveInterval();
LiveRange* range = interval->GetFirstRange();
ASSERT_EQ(2u, range->GetStart());
// Last use is the return instruction.
ASSERT_EQ(8u, range->GetEnd());
HBasicBlock* block = graph->GetBlocks()[1];
ASSERT_TRUE(block->GetLastInstruction()->IsReturn());
ASSERT_EQ(8u, block->GetLastInstruction()->GetLifetimePosition());
ASSERT_TRUE(range->GetNext() == nullptr);
}
TEST_F(LiveRangesTest, CFG2) {
/*
* Test the following snippet:
* var a = 0;
* if (0 == 0) {
* } else {
* }
* return a;
*
* Which becomes the following graph (numbered by lifetime position):
* 2: constant0
* 4: goto
* |
* 8: equal
* 10: if
* / \
* 14: goto 18: goto
* \ /
* 22: return
* |
* 26: exit
*/
const std::vector<uint16_t> data = ONE_REGISTER_CODE_ITEM(
Instruction::CONST_4 | 0 | 0,
Instruction::IF_EQ, 3,
Instruction::GOTO | 0x100,
Instruction::RETURN | 0 << 8);
HGraph* graph = BuildGraph(data);
std::unique_ptr<CodeGenerator> codegen = CodeGenerator::Create(graph, *compiler_options_);
SsaLivenessAnalysis liveness(graph, codegen.get(), GetScopedAllocator());
liveness.Analyze();
LiveInterval* interval = liveness.GetInstructionFromSsaIndex(0)->GetLiveInterval();
LiveRange* range = interval->GetFirstRange();
ASSERT_EQ(2u, range->GetStart());
// Last use is the return instruction.
ASSERT_EQ(22u, range->GetEnd());
HBasicBlock* block = graph->GetBlocks()[3];
ASSERT_TRUE(block->GetLastInstruction()->IsReturn());
ASSERT_EQ(22u, block->GetLastInstruction()->GetLifetimePosition());
ASSERT_TRUE(range->GetNext() == nullptr);
}
TEST_F(LiveRangesTest, CFG3) {
/*
* Test the following snippet:
* var a = 0;
* if (0 == 0) {
* } else {
* a = 4;
* }
* return a;
*
* Which becomes the following graph (numbered by lifetime position):
* 2: constant0
* 4: constant4
* 6: goto
* |
* 10: equal
* 12: if
* / \
* 16: goto 20: goto
* \ /
* 22: phi
* 24: return
* |
* 28: exit
*/
const std::vector<uint16_t> data = ONE_REGISTER_CODE_ITEM(
Instruction::CONST_4 | 0 | 0,
Instruction::IF_EQ, 3,
Instruction::CONST_4 | 4 << 12 | 0,
Instruction::RETURN | 0 << 8);
HGraph* graph = BuildGraph(data);
std::unique_ptr<CodeGenerator> codegen = CodeGenerator::Create(graph, *compiler_options_);
SsaLivenessAnalysis liveness(graph, codegen.get(), GetScopedAllocator());
liveness.Analyze();
// Test for the 4 constant.
LiveInterval* interval = liveness.GetInstructionFromSsaIndex(1)->GetLiveInterval();
LiveRange* range = interval->GetFirstRange();
ASSERT_EQ(4u, range->GetStart());
// Last use is the phi at the return block so instruction is live until
// the end of the then block.
ASSERT_EQ(18u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the 0 constant.
interval = liveness.GetInstructionFromSsaIndex(0)->GetLiveInterval();
// The then branch is a hole for this constant, therefore its interval has 2 ranges.
// First range starts from the definition and ends at the if block.
range = interval->GetFirstRange();
ASSERT_EQ(2u, range->GetStart());
// 14 is the end of the if block.
ASSERT_EQ(14u, range->GetEnd());
// Second range is the else block.
range = range->GetNext();
ASSERT_EQ(18u, range->GetStart());
// Last use is the phi at the return block.
ASSERT_EQ(22u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the phi.
interval = liveness.GetInstructionFromSsaIndex(2)->GetLiveInterval();
range = interval->GetFirstRange();
ASSERT_EQ(22u, liveness.GetInstructionFromSsaIndex(2)->GetLifetimePosition());
ASSERT_EQ(22u, range->GetStart());
ASSERT_EQ(24u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
}
TEST_F(LiveRangesTest, Loop1) {
/*
* Test the following snippet:
* var a = 0;
* while (a == a) {
* a = 4;
* }
* return 5;
*
* Which becomes the following graph (numbered by lifetime position):
* 2: constant0
* 4: constant5
* 6: constant4
* 8: goto
* |
* 12: goto
* |
* 14: phi
* 16: equal
* 18: if +++++
* | \ +
* | 22: goto
* |
* 26: return
* |
* 30: exit
*/
const std::vector<uint16_t> data = TWO_REGISTERS_CODE_ITEM(
Instruction::CONST_4 | 0 | 0,
Instruction::IF_EQ, 4,
Instruction::CONST_4 | 4 << 12 | 0,
Instruction::GOTO | 0xFD00,
Instruction::CONST_4 | 5 << 12 | 1 << 8,
Instruction::RETURN | 1 << 8);
HGraph* graph = BuildGraph(data);
RemoveSuspendChecks(graph);
std::unique_ptr<CodeGenerator> codegen = CodeGenerator::Create(graph, *compiler_options_);
SsaLivenessAnalysis liveness(graph, codegen.get(), GetScopedAllocator());
liveness.Analyze();
// Test for the 0 constant.
LiveInterval* interval = graph->GetIntConstant(0)->GetLiveInterval();
LiveRange* range = interval->GetFirstRange();
ASSERT_EQ(2u, range->GetStart());
// Last use is the loop phi so instruction is live until
// the end of the pre loop header.
ASSERT_EQ(14u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the 4 constant.
interval = graph->GetIntConstant(4)->GetLiveInterval();
range = interval->GetFirstRange();
// The instruction is live until the end of the loop.
ASSERT_EQ(6u, range->GetStart());
ASSERT_EQ(24u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the 5 constant.
interval = graph->GetIntConstant(5)->GetLiveInterval();
range = interval->GetFirstRange();
// The instruction is live until the return instruction after the loop.
ASSERT_EQ(4u, range->GetStart());
ASSERT_EQ(26u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the phi.
interval = liveness.GetInstructionFromSsaIndex(3)->GetLiveInterval();
range = interval->GetFirstRange();
// Instruction is input of non-materialized Equal and hence live until If.
ASSERT_EQ(14u, range->GetStart());
ASSERT_EQ(19u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
}
TEST_F(LiveRangesTest, Loop2) {
/*
* Test the following snippet:
* var a = 0;
* while (a == a) {
* a = a + a;
* }
* return a;
*
* Which becomes the following graph (numbered by lifetime position):
* 2: constant0
* 4: goto
* |
* 8: goto
* |
* 10: phi
* 12: equal
* 14: if +++++
* | \ +
* | 18: add
* | 20: goto
* |
* 24: return
* |
* 28: exit
*
* We want to make sure the phi at 10 has a lifetime hole after the add at 20.
*/
const std::vector<uint16_t> data = ONE_REGISTER_CODE_ITEM(
Instruction::CONST_4 | 0 | 0,
Instruction::IF_EQ, 6,
Instruction::ADD_INT, 0, 0,
Instruction::GOTO | 0xFB00,
Instruction::RETURN | 0 << 8);
HGraph* graph = BuildGraph(data);
std::unique_ptr<CodeGenerator> codegen = CodeGenerator::Create(graph, *compiler_options_);
SsaLivenessAnalysis liveness(graph, codegen.get(), GetScopedAllocator());
liveness.Analyze();
// Test for the 0 constant.
HIntConstant* constant = liveness.GetInstructionFromSsaIndex(0)->AsIntConstant();
LiveInterval* interval = constant->GetLiveInterval();
LiveRange* range = interval->GetFirstRange();
ASSERT_EQ(2u, range->GetStart());
// Last use is the loop phi so instruction is live until
// the end of the pre loop header.
ASSERT_EQ(10u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the loop phi.
HPhi* phi = liveness.GetInstructionFromSsaIndex(1)->AsPhi();
interval = phi->GetLiveInterval();
range = interval->GetFirstRange();
ASSERT_EQ(10u, range->GetStart());
ASSERT_EQ(19u, range->GetEnd());
range = range->GetNext();
ASSERT_TRUE(range != nullptr);
ASSERT_EQ(22u, range->GetStart());
ASSERT_EQ(24u, range->GetEnd());
// Test for the add instruction.
HAdd* add = liveness.GetInstructionFromSsaIndex(2)->AsAdd();
interval = add->GetLiveInterval();
range = interval->GetFirstRange();
ASSERT_EQ(18u, range->GetStart());
ASSERT_EQ(22u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
}
TEST_F(LiveRangesTest, CFG4) {
/*
* Test the following snippet:
* var a = 0;
* var b = 4;
* if (a == a) {
* a = b + a;
* } else {
* a = b + a
* }
* return b;
*
* Which becomes the following graph (numbered by lifetime position):
* 2: constant0
* 4: constant4
* 6: goto
* |
* 10: equal
* 12: if
* / \
* 16: add 22: add
* 18: goto 24: goto
* \ /
* 26: phi
* 28: return
* |
* 32: exit
*
* We want to make sure the constant0 has a lifetime hole after the 16: add.
*/
const std::vector<uint16_t> data = TWO_REGISTERS_CODE_ITEM(
Instruction::CONST_4 | 0 | 0,
Instruction::CONST_4 | 4 << 12 | 1 << 8,
Instruction::IF_EQ, 5,
Instruction::ADD_INT, 1 << 8,
Instruction::GOTO | 0x300,
Instruction::ADD_INT, 1 << 8,
Instruction::RETURN);
HGraph* graph = BuildGraph(data);
std::unique_ptr<CodeGenerator> codegen = CodeGenerator::Create(graph, *compiler_options_);
SsaLivenessAnalysis liveness(graph, codegen.get(), GetScopedAllocator());
liveness.Analyze();
// Test for the 0 constant.
LiveInterval* interval = liveness.GetInstructionFromSsaIndex(0)->GetLiveInterval();
LiveRange* range = interval->GetFirstRange();
ASSERT_EQ(2u, range->GetStart());
ASSERT_EQ(17u, range->GetEnd());
range = range->GetNext();
ASSERT_TRUE(range != nullptr);
ASSERT_EQ(20u, range->GetStart());
ASSERT_EQ(23u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the 4 constant.
interval = liveness.GetInstructionFromSsaIndex(1)->GetLiveInterval();
range = interval->GetFirstRange();
ASSERT_EQ(4u, range->GetStart());
ASSERT_EQ(17u, range->GetEnd());
range = range->GetNext();
ASSERT_EQ(20u, range->GetStart());
ASSERT_EQ(23u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the first add.
HAdd* add = liveness.GetInstructionFromSsaIndex(2)->AsAdd();
interval = add->GetLiveInterval();
range = interval->GetFirstRange();
ASSERT_EQ(16u, range->GetStart());
ASSERT_EQ(20u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
// Test for the second add.
add = liveness.GetInstructionFromSsaIndex(3)->AsAdd();
interval = add->GetLiveInterval();
range = interval->GetFirstRange();
ASSERT_EQ(22u, range->GetStart());
ASSERT_EQ(26u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
HPhi* phi = liveness.GetInstructionFromSsaIndex(4)->AsPhi();
ASSERT_TRUE(phi->GetUses().HasExactlyOneElement());
interval = phi->GetLiveInterval();
range = interval->GetFirstRange();
ASSERT_EQ(26u, range->GetStart());
ASSERT_EQ(28u, range->GetEnd());
ASSERT_TRUE(range->GetNext() == nullptr);
}
} // namespace art