| /* |
| * 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 "constant_propagation.h" |
| #include "dead_code_elimination.h" |
| #include "pretty_printer.h" |
| #include "graph_checker.h" |
| #include "optimizing_unit_test.h" |
| |
| #include "gtest/gtest.h" |
| |
| namespace art { |
| |
| static void TestCode(const uint16_t* data, |
| const std::string& expected_before, |
| const std::string& expected_after_cp, |
| const std::string& expected_after_dce) { |
| ArenaPool pool; |
| ArenaAllocator allocator(&pool); |
| HGraph* graph = CreateCFG(&allocator, data); |
| ASSERT_NE(graph, nullptr); |
| |
| graph->BuildDominatorTree(); |
| graph->TransformToSSA(); |
| |
| StringPrettyPrinter printer_before(graph); |
| printer_before.VisitInsertionOrder(); |
| std::string actual_before = printer_before.str(); |
| ASSERT_EQ(expected_before, actual_before); |
| |
| ConstantPropagation(graph).Run(); |
| |
| StringPrettyPrinter printer_after_cp(graph); |
| printer_after_cp.VisitInsertionOrder(); |
| std::string actual_after_cp = printer_after_cp.str(); |
| ASSERT_EQ(expected_after_cp, actual_after_cp); |
| |
| DeadCodeElimination(graph).Run(); |
| |
| StringPrettyPrinter printer_after_dce(graph); |
| printer_after_dce.VisitInsertionOrder(); |
| std::string actual_after_dce = printer_after_dce.str(); |
| ASSERT_EQ(expected_after_dce, actual_after_dce); |
| |
| SSAChecker ssa_checker(&allocator, graph); |
| ssa_checker.VisitInsertionOrder(); |
| ASSERT_TRUE(ssa_checker.IsValid()); |
| } |
| |
| |
| /** |
| * Tiny three-register program exercising int constant folding on addition. |
| * |
| * 16-bit |
| * offset |
| * ------ |
| * v0 <- 1 0. const/4 v0, #+1 |
| * v1 <- 2 1. const/4 v1, #+2 |
| * v2 <- v0 + v1 2. add-int v2, v0, v1 |
| * return v2 4. return v2 |
| */ |
| TEST(ConstantPropagation, IntConstantFoldingOnAddition1) { |
| const uint16_t data[] = THREE_REGISTERS_CODE_ITEM( |
| Instruction::CONST_4 | 0 << 8 | 1 << 12, |
| Instruction::CONST_4 | 1 << 8 | 2 << 12, |
| Instruction::ADD_INT | 2 << 8, 0 | 1 << 8, |
| Instruction::RETURN | 2 << 8); |
| |
| std::string expected_before = |
| "BasicBlock 0, succ: 1\n" |
| " 3: IntConstant [9]\n" |
| " 5: IntConstant [9]\n" |
| " 14: SuspendCheck\n" |
| " 15: Goto 1\n" |
| "BasicBlock 1, pred: 0, succ: 2\n" |
| " 9: Add(3, 5) [12]\n" |
| " 12: Return(9)\n" |
| "BasicBlock 2, pred: 1\n" |
| " 13: Exit\n"; |
| |
| // Expected difference after constant propagation. |
| diff_t expected_cp_diff = { |
| { " 3: IntConstant [9]\n", " 3: IntConstant\n" }, |
| { " 5: IntConstant [9]\n", " 5: IntConstant\n" }, |
| { " 9: Add(3, 5) [12]\n", " 16: IntConstant [12]\n" }, |
| { " 12: Return(9)\n", " 12: Return(16)\n" } |
| }; |
| std::string expected_after_cp = Patch(expected_before, expected_cp_diff); |
| |
| // Expected difference after dead code elimination. |
| diff_t expected_dce_diff = { |
| { " 3: IntConstant\n", removed }, |
| { " 5: IntConstant\n", removed } |
| }; |
| std::string expected_after_dce = Patch(expected_after_cp, expected_dce_diff); |
| |
| TestCode(data, expected_before, expected_after_cp, expected_after_dce); |
| } |
| |
| /** |
| * Small three-register program exercising int constant folding on addition. |
| * |
| * 16-bit |
| * offset |
| * ------ |
| * v0 <- 1 0. const/4 v0, #+1 |
| * v1 <- 2 1. const/4 v1, #+2 |
| * v0 <- v0 + v1 2. add-int/2addr v0, v1 |
| * v1 <- 3 3. const/4 v1, #+3 |
| * v2 <- 4 4. const/4 v2, #+4 |
| * v1 <- v1 + v2 5. add-int/2addr v1, v2 |
| * v2 <- v0 + v1 6. add-int v2, v0, v1 |
| * return v2 8. return v2 |
| */ |
| TEST(ConstantPropagation, IntConstantFoldingOnAddition2) { |
| const uint16_t data[] = THREE_REGISTERS_CODE_ITEM( |
| Instruction::CONST_4 | 0 << 8 | 1 << 12, |
| Instruction::CONST_4 | 1 << 8 | 2 << 12, |
| Instruction::ADD_INT_2ADDR | 0 << 8 | 1 << 12, |
| Instruction::CONST_4 | 1 << 8 | 3 << 12, |
| Instruction::CONST_4 | 2 << 8 | 4 << 12, |
| Instruction::ADD_INT_2ADDR | 1 << 8 | 2 << 12, |
| Instruction::ADD_INT | 2 << 8, 0 | 1 << 8, |
| Instruction::RETURN | 2 << 8); |
| |
| std::string expected_before = |
| "BasicBlock 0, succ: 1\n" |
| " 3: IntConstant [9]\n" |
| " 5: IntConstant [9]\n" |
| " 11: IntConstant [17]\n" |
| " 13: IntConstant [17]\n" |
| " 26: SuspendCheck\n" |
| " 27: Goto 1\n" |
| "BasicBlock 1, pred: 0, succ: 2\n" |
| " 9: Add(3, 5) [21]\n" |
| " 17: Add(11, 13) [21]\n" |
| " 21: Add(9, 17) [24]\n" |
| " 24: Return(21)\n" |
| "BasicBlock 2, pred: 1\n" |
| " 25: Exit\n"; |
| |
| // Expected difference after constant propagation. |
| diff_t expected_cp_diff = { |
| { " 3: IntConstant [9]\n", " 3: IntConstant\n" }, |
| { " 5: IntConstant [9]\n", " 5: IntConstant\n" }, |
| { " 11: IntConstant [17]\n", " 11: IntConstant\n" }, |
| { " 13: IntConstant [17]\n", " 13: IntConstant\n" }, |
| { " 9: Add(3, 5) [21]\n", " 28: IntConstant\n" }, |
| { " 17: Add(11, 13) [21]\n", " 29: IntConstant\n" }, |
| { " 21: Add(9, 17) [24]\n", " 30: IntConstant [24]\n" }, |
| { " 24: Return(21)\n", " 24: Return(30)\n" } |
| }; |
| std::string expected_after_cp = Patch(expected_before, expected_cp_diff); |
| |
| // Expected difference after dead code elimination. |
| diff_t expected_dce_diff = { |
| { " 3: IntConstant\n", removed }, |
| { " 5: IntConstant\n", removed }, |
| { " 11: IntConstant\n", removed }, |
| { " 13: IntConstant\n", removed }, |
| { " 28: IntConstant\n", removed }, |
| { " 29: IntConstant\n", removed } |
| }; |
| std::string expected_after_dce = Patch(expected_after_cp, expected_dce_diff); |
| |
| TestCode(data, expected_before, expected_after_cp, expected_after_dce); |
| } |
| |
| /** |
| * Tiny three-register program exercising int constant folding on subtraction. |
| * |
| * 16-bit |
| * offset |
| * ------ |
| * v0 <- 3 0. const/4 v0, #+3 |
| * v1 <- 2 1. const/4 v1, #+2 |
| * v2 <- v0 - v1 2. sub-int v2, v0, v1 |
| * return v2 4. return v2 |
| */ |
| TEST(ConstantPropagation, IntConstantFoldingOnSubtraction) { |
| const uint16_t data[] = THREE_REGISTERS_CODE_ITEM( |
| Instruction::CONST_4 | 0 << 8 | 3 << 12, |
| Instruction::CONST_4 | 1 << 8 | 2 << 12, |
| Instruction::SUB_INT | 2 << 8, 0 | 1 << 8, |
| Instruction::RETURN | 2 << 8); |
| |
| std::string expected_before = |
| "BasicBlock 0, succ: 1\n" |
| " 3: IntConstant [9]\n" |
| " 5: IntConstant [9]\n" |
| " 14: SuspendCheck\n" |
| " 15: Goto 1\n" |
| "BasicBlock 1, pred: 0, succ: 2\n" |
| " 9: Sub(3, 5) [12]\n" |
| " 12: Return(9)\n" |
| "BasicBlock 2, pred: 1\n" |
| " 13: Exit\n"; |
| |
| // Expected difference after constant propagation. |
| diff_t expected_cp_diff = { |
| { " 3: IntConstant [9]\n", " 3: IntConstant\n" }, |
| { " 5: IntConstant [9]\n", " 5: IntConstant\n" }, |
| { " 9: Sub(3, 5) [12]\n", " 16: IntConstant [12]\n" }, |
| { " 12: Return(9)\n", " 12: Return(16)\n" } |
| }; |
| std::string expected_after_cp = Patch(expected_before, expected_cp_diff); |
| |
| // Expected difference after dead code elimination. |
| diff_t expected_dce_diff = { |
| { " 3: IntConstant\n", removed }, |
| { " 5: IntConstant\n", removed } |
| }; |
| std::string expected_after_dce = Patch(expected_after_cp, expected_dce_diff); |
| |
| TestCode(data, expected_before, expected_after_cp, expected_after_dce); |
| } |
| |
| #define SIX_REGISTERS_CODE_ITEM(...) \ |
| { 6, 0, 0, 0, 0, 0, NUM_INSTRUCTIONS(__VA_ARGS__), 0, __VA_ARGS__ } |
| |
| /** |
| * Tiny three-register-pair program exercising long constant folding |
| * on addition. |
| * |
| * 16-bit |
| * offset |
| * ------ |
| * (v0, v1) <- 1 0. const-wide/16 v0, #+1 |
| * (v2, v3) <- 2 2. const-wide/16 v2, #+2 |
| * (v4, v5) <- |
| * (v0, v1) + (v1, v2) 4. add-long v4, v0, v2 |
| * return (v4, v5) 6. return-wide v4 |
| */ |
| TEST(ConstantPropagation, LongConstantFoldingOnAddition) { |
| const uint16_t data[] = SIX_REGISTERS_CODE_ITEM( |
| Instruction::CONST_WIDE_16 | 0 << 8, 1, |
| Instruction::CONST_WIDE_16 | 2 << 8, 2, |
| Instruction::ADD_LONG | 4 << 8, 0 | 2 << 8, |
| Instruction::RETURN_WIDE | 4 << 8); |
| |
| std::string expected_before = |
| "BasicBlock 0, succ: 1\n" |
| " 6: LongConstant [12]\n" |
| " 8: LongConstant [12]\n" |
| " 17: SuspendCheck\n" |
| " 18: Goto 1\n" |
| "BasicBlock 1, pred: 0, succ: 2\n" |
| " 12: Add(6, 8) [15]\n" |
| " 15: Return(12)\n" |
| "BasicBlock 2, pred: 1\n" |
| " 16: Exit\n"; |
| |
| // Expected difference after constant propagation. |
| diff_t expected_cp_diff = { |
| { " 6: LongConstant [12]\n", " 6: LongConstant\n" }, |
| { " 8: LongConstant [12]\n", " 8: LongConstant\n" }, |
| { " 12: Add(6, 8) [15]\n", " 19: LongConstant [15]\n" }, |
| { " 15: Return(12)\n", " 15: Return(19)\n" } |
| }; |
| std::string expected_after_cp = Patch(expected_before, expected_cp_diff); |
| |
| // Expected difference after dead code elimination. |
| diff_t expected_dce_diff = { |
| { " 6: LongConstant\n", removed }, |
| { " 8: LongConstant\n", removed } |
| }; |
| std::string expected_after_dce = Patch(expected_after_cp, expected_dce_diff); |
| |
| TestCode(data, expected_before, expected_after_cp, expected_after_dce); |
| } |
| |
| /** |
| * Tiny three-register-pair program exercising long constant folding |
| * on subtraction. |
| * |
| * 16-bit |
| * offset |
| * ------ |
| * (v0, v1) <- 3 0. const-wide/16 v0, #+3 |
| * (v2, v3) <- 2 2. const-wide/16 v2, #+2 |
| * (v4, v5) <- |
| * (v0, v1) - (v1, v2) 4. sub-long v4, v0, v2 |
| * return (v4, v5) 6. return-wide v4 |
| */ |
| TEST(ConstantPropagation, LongConstantFoldingOnSubtraction) { |
| const uint16_t data[] = SIX_REGISTERS_CODE_ITEM( |
| Instruction::CONST_WIDE_16 | 0 << 8, 3, |
| Instruction::CONST_WIDE_16 | 2 << 8, 2, |
| Instruction::SUB_LONG | 4 << 8, 0 | 2 << 8, |
| Instruction::RETURN_WIDE | 4 << 8); |
| |
| std::string expected_before = |
| "BasicBlock 0, succ: 1\n" |
| " 6: LongConstant [12]\n" |
| " 8: LongConstant [12]\n" |
| " 17: SuspendCheck\n" |
| " 18: Goto 1\n" |
| "BasicBlock 1, pred: 0, succ: 2\n" |
| " 12: Sub(6, 8) [15]\n" |
| " 15: Return(12)\n" |
| "BasicBlock 2, pred: 1\n" |
| " 16: Exit\n"; |
| |
| // Expected difference after constant propagation. |
| diff_t expected_cp_diff = { |
| { " 6: LongConstant [12]\n", " 6: LongConstant\n" }, |
| { " 8: LongConstant [12]\n", " 8: LongConstant\n" }, |
| { " 12: Sub(6, 8) [15]\n", " 19: LongConstant [15]\n" }, |
| { " 15: Return(12)\n", " 15: Return(19)\n" } |
| }; |
| std::string expected_after_cp = Patch(expected_before, expected_cp_diff); |
| |
| // Expected difference after dead code elimination. |
| diff_t expected_dce_diff = { |
| { " 6: LongConstant\n", removed }, |
| { " 8: LongConstant\n", removed } |
| }; |
| std::string expected_after_dce = Patch(expected_after_cp, expected_dce_diff); |
| |
| TestCode(data, expected_before, expected_after_cp, expected_after_dce); |
| } |
| |
| /** |
| * Three-register program with jumps leading to the creation of many |
| * blocks. |
| * |
| * The intent of this test is to ensure that all constant expressions |
| * are actually evaluated at compile-time, thanks to the reverse |
| * (forward) post-order traversal of the the dominator tree. |
| * |
| * 16-bit |
| * offset |
| * ------ |
| * v0 <- 0 0. const/4 v0, #+0 |
| * v1 <- 1 1. const/4 v1, #+1 |
| * v2 <- v0 + v1 2. add-int v2, v0, v1 |
| * goto L2 4. goto +4 |
| * L1: v1 <- v0 + 3 5. add-int/lit16 v1, v0, #+3 |
| * goto L3 7. goto +4 |
| * L2: v0 <- v2 + 2 8. add-int/lit16 v0, v2, #+2 |
| * goto L1 10. goto +(-5) |
| * L3: v2 <- v1 + 4 11. add-int/lit16 v2, v1, #+4 |
| * return v2 13. return v2 |
| */ |
| TEST(ConstantPropagation, IntConstantFoldingAndJumps) { |
| const uint16_t data[] = THREE_REGISTERS_CODE_ITEM( |
| Instruction::CONST_4 | 0 << 8 | 0 << 12, |
| Instruction::CONST_4 | 1 << 8 | 1 << 12, |
| Instruction::ADD_INT | 2 << 8, 0 | 1 << 8, |
| Instruction::GOTO | 4 << 8, |
| Instruction::ADD_INT_LIT16 | 1 << 8 | 0 << 12, 3, |
| Instruction::GOTO | 4 << 8, |
| Instruction::ADD_INT_LIT16 | 0 << 8 | 2 << 12, 2, |
| static_cast<uint16_t>(Instruction::GOTO | -5 << 8), |
| Instruction::ADD_INT_LIT16 | 2 << 8 | 1 << 12, 4, |
| Instruction::RETURN | 2 << 8); |
| |
| std::string expected_before = |
| "BasicBlock 0, succ: 1\n" |
| " 3: IntConstant [9]\n" |
| " 5: IntConstant [9]\n" |
| " 13: IntConstant [14]\n" |
| " 18: IntConstant [19]\n" |
| " 24: IntConstant [25]\n" |
| " 30: SuspendCheck\n" |
| " 31: Goto 1\n" |
| "BasicBlock 1, pred: 0, succ: 3\n" |
| " 9: Add(3, 5) [19]\n" |
| " 11: Goto 3\n" |
| "BasicBlock 2, pred: 3, succ: 4\n" |
| " 14: Add(19, 13) [25]\n" |
| " 16: Goto 4\n" |
| "BasicBlock 3, pred: 1, succ: 2\n" |
| " 19: Add(9, 18) [14]\n" |
| " 21: SuspendCheck\n" |
| " 22: Goto 2\n" |
| "BasicBlock 4, pred: 2, succ: 5\n" |
| " 25: Add(14, 24) [28]\n" |
| " 28: Return(25)\n" |
| "BasicBlock 5, pred: 4\n" |
| " 29: Exit\n"; |
| |
| // Expected difference after constant propagation. |
| diff_t expected_cp_diff = { |
| { " 3: IntConstant [9]\n", " 3: IntConstant\n" }, |
| { " 5: IntConstant [9]\n", " 5: IntConstant []\n" }, |
| { " 13: IntConstant [14]\n", " 13: IntConstant\n" }, |
| { " 18: IntConstant [19]\n", " 18: IntConstant\n" }, |
| { " 24: IntConstant [25]\n", " 24: IntConstant\n" }, |
| { " 9: Add(3, 5) [19]\n", " 32: IntConstant []\n" }, |
| { " 14: Add(19, 13) [25]\n", " 34: IntConstant\n" }, |
| { " 19: Add(9, 18) [14]\n", " 33: IntConstant []\n" }, |
| { " 25: Add(14, 24) [28]\n", " 35: IntConstant [28]\n" }, |
| { " 28: Return(25)\n", " 28: Return(35)\n"} |
| }; |
| std::string expected_after_cp = Patch(expected_before, expected_cp_diff); |
| |
| // Expected difference after dead code elimination. |
| diff_t expected_dce_diff = { |
| { " 3: IntConstant\n", removed }, |
| { " 13: IntConstant\n", removed }, |
| { " 18: IntConstant\n", removed }, |
| { " 24: IntConstant\n", removed }, |
| { " 34: IntConstant\n", removed }, |
| }; |
| std::string expected_after_dce = Patch(expected_after_cp, expected_dce_diff); |
| |
| TestCode(data, expected_before, expected_after_cp, expected_after_dce); |
| } |
| |
| |
| /** |
| * Three-register program with a constant (static) condition. |
| * |
| * 16-bit |
| * offset |
| * ------ |
| * v1 <- 1 0. const/4 v1, #+1 |
| * v0 <- 0 1. const/4 v0, #+0 |
| * if v1 >= 0 goto L1 2. if-gez v1, +3 |
| * v0 <- v1 4. move v0, v1 |
| * L1: v2 <- v0 + v1 5. add-int v2, v0, v1 |
| * return-void 7. return |
| */ |
| TEST(ConstantPropagation, ConstantCondition) { |
| const uint16_t data[] = THREE_REGISTERS_CODE_ITEM( |
| Instruction::CONST_4 | 1 << 8 | 1 << 12, |
| Instruction::CONST_4 | 0 << 8 | 0 << 12, |
| Instruction::IF_GEZ | 1 << 8, 3, |
| Instruction::MOVE | 0 << 8 | 1 << 12, |
| Instruction::ADD_INT | 2 << 8, 0 | 1 << 8, |
| Instruction::RETURN_VOID); |
| |
| std::string expected_before = |
| "BasicBlock 0, succ: 1\n" |
| " 3: IntConstant [15, 22, 8]\n" |
| " 5: IntConstant [22, 8]\n" |
| " 19: SuspendCheck\n" |
| " 20: Goto 1\n" |
| "BasicBlock 1, pred: 0, succ: 5, 2\n" |
| " 8: GreaterThanOrEqual(3, 5) [9]\n" |
| " 9: If(8)\n" |
| "BasicBlock 2, pred: 1, succ: 3\n" |
| " 12: Goto 3\n" |
| "BasicBlock 3, pred: 2, 5, succ: 4\n" |
| " 22: Phi(3, 5) [15]\n" |
| " 15: Add(22, 3)\n" |
| " 17: ReturnVoid\n" |
| "BasicBlock 4, pred: 3\n" |
| " 18: Exit\n" |
| "BasicBlock 5, pred: 1, succ: 3\n" |
| " 21: Goto 3\n"; |
| |
| // Expected difference after constant propagation. |
| diff_t expected_cp_diff = { |
| { " 3: IntConstant [15, 22, 8]\n", " 3: IntConstant [15, 22]\n" }, |
| { " 5: IntConstant [22, 8]\n", " 5: IntConstant [22]\n" }, |
| { " 8: GreaterThanOrEqual(3, 5) [9]\n", " 23: IntConstant [9]\n" }, |
| { " 9: If(8)\n", " 9: If(23)\n" } |
| }; |
| std::string expected_after_cp = Patch(expected_before, expected_cp_diff); |
| |
| // Expected difference after dead code elimination. |
| diff_t expected_dce_diff = { |
| { " 3: IntConstant [15, 22]\n", " 3: IntConstant [22]\n" }, |
| { " 22: Phi(3, 5) [15]\n", " 22: Phi(3, 5)\n" }, |
| { " 15: Add(22, 3)\n", removed } |
| }; |
| std::string expected_after_dce = Patch(expected_after_cp, expected_dce_diff); |
| |
| TestCode(data, expected_before, expected_after_cp, expected_after_dce); |
| } |
| |
| } // namespace art |
