Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2015 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #ifndef V8_INTERPRETER_CONTROL_FLOW_BUILDERS_H_ |
| 6 | #define V8_INTERPRETER_CONTROL_FLOW_BUILDERS_H_ |
| 7 | |
| 8 | #include "src/interpreter/bytecode-array-builder.h" |
| 9 | |
Ben Murdoch | 61f157c | 2016-09-16 13:49:30 +0100 | [diff] [blame] | 10 | #include "src/interpreter/bytecode-label.h" |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 11 | #include "src/zone-containers.h" |
| 12 | |
| 13 | namespace v8 { |
| 14 | namespace internal { |
| 15 | namespace interpreter { |
| 16 | |
| 17 | class ControlFlowBuilder BASE_EMBEDDED { |
| 18 | public: |
| 19 | explicit ControlFlowBuilder(BytecodeArrayBuilder* builder) |
| 20 | : builder_(builder) {} |
| 21 | virtual ~ControlFlowBuilder() {} |
| 22 | |
| 23 | protected: |
| 24 | BytecodeArrayBuilder* builder() const { return builder_; } |
| 25 | |
| 26 | private: |
| 27 | BytecodeArrayBuilder* builder_; |
| 28 | |
| 29 | DISALLOW_COPY_AND_ASSIGN(ControlFlowBuilder); |
| 30 | }; |
| 31 | |
| 32 | class BreakableControlFlowBuilder : public ControlFlowBuilder { |
| 33 | public: |
| 34 | explicit BreakableControlFlowBuilder(BytecodeArrayBuilder* builder) |
| 35 | : ControlFlowBuilder(builder), |
| 36 | break_sites_(builder->zone()) {} |
| 37 | virtual ~BreakableControlFlowBuilder(); |
| 38 | |
| 39 | // This method should be called by the control flow owner before |
| 40 | // destruction to update sites that emit jumps for break. |
| 41 | void SetBreakTarget(const BytecodeLabel& break_target); |
| 42 | |
| 43 | // This method is called when visiting break statements in the AST. |
| 44 | // Inserts a jump to a unbound label that is patched when the corresponding |
| 45 | // SetBreakTarget is called. |
| 46 | void Break() { EmitJump(&break_sites_); } |
| 47 | void BreakIfTrue() { EmitJumpIfTrue(&break_sites_); } |
| 48 | void BreakIfFalse() { EmitJumpIfFalse(&break_sites_); } |
| 49 | void BreakIfUndefined() { EmitJumpIfUndefined(&break_sites_); } |
| 50 | void BreakIfNull() { EmitJumpIfNull(&break_sites_); } |
| 51 | |
| 52 | protected: |
| 53 | void EmitJump(ZoneVector<BytecodeLabel>* labels); |
| 54 | void EmitJump(ZoneVector<BytecodeLabel>* labels, int index); |
| 55 | void EmitJumpIfTrue(ZoneVector<BytecodeLabel>* labels); |
| 56 | void EmitJumpIfTrue(ZoneVector<BytecodeLabel>* labels, int index); |
| 57 | void EmitJumpIfFalse(ZoneVector<BytecodeLabel>* labels); |
| 58 | void EmitJumpIfFalse(ZoneVector<BytecodeLabel>* labels, int index); |
| 59 | void EmitJumpIfUndefined(ZoneVector<BytecodeLabel>* labels); |
| 60 | void EmitJumpIfNull(ZoneVector<BytecodeLabel>* labels); |
| 61 | |
| 62 | void BindLabels(const BytecodeLabel& target, ZoneVector<BytecodeLabel>* site); |
| 63 | |
| 64 | // Unbound labels that identify jumps for break statements in the code. |
| 65 | ZoneVector<BytecodeLabel> break_sites_; |
| 66 | }; |
| 67 | |
| 68 | |
| 69 | // Class to track control flow for block statements (which can break in JS). |
| 70 | class BlockBuilder final : public BreakableControlFlowBuilder { |
| 71 | public: |
| 72 | explicit BlockBuilder(BytecodeArrayBuilder* builder) |
| 73 | : BreakableControlFlowBuilder(builder) {} |
| 74 | |
| 75 | void EndBlock(); |
| 76 | |
| 77 | private: |
| 78 | BytecodeLabel block_end_; |
| 79 | }; |
| 80 | |
| 81 | |
| 82 | // A class to help with co-ordinating break and continue statements with |
| 83 | // their loop. |
| 84 | class LoopBuilder final : public BreakableControlFlowBuilder { |
| 85 | public: |
| 86 | explicit LoopBuilder(BytecodeArrayBuilder* builder) |
| 87 | : BreakableControlFlowBuilder(builder), |
| 88 | continue_sites_(builder->zone()) {} |
| 89 | ~LoopBuilder(); |
| 90 | |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 91 | void LoopHeader(ZoneVector<BytecodeLabel>* additional_labels); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 92 | void JumpToHeader() { builder()->Jump(&loop_header_); } |
| 93 | void JumpToHeaderIfTrue() { builder()->JumpIfTrue(&loop_header_); } |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 94 | void SetContinueTarget(); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 95 | void EndLoop(); |
| 96 | |
| 97 | // This method is called when visiting continue statements in the AST. |
Ben Murdoch | c561043 | 2016-08-08 18:44:38 +0100 | [diff] [blame] | 98 | // Inserts a jump to an unbound label that is patched when SetContinueTarget |
| 99 | // is called. |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 100 | void Continue() { EmitJump(&continue_sites_); } |
| 101 | void ContinueIfTrue() { EmitJumpIfTrue(&continue_sites_); } |
| 102 | void ContinueIfUndefined() { EmitJumpIfUndefined(&continue_sites_); } |
| 103 | void ContinueIfNull() { EmitJumpIfNull(&continue_sites_); } |
| 104 | |
| 105 | private: |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 106 | BytecodeLabel loop_header_; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 107 | BytecodeLabel loop_end_; |
| 108 | |
| 109 | // Unbound labels that identify jumps for continue statements in the code. |
| 110 | ZoneVector<BytecodeLabel> continue_sites_; |
| 111 | }; |
| 112 | |
| 113 | |
| 114 | // A class to help with co-ordinating break statements with their switch. |
| 115 | class SwitchBuilder final : public BreakableControlFlowBuilder { |
| 116 | public: |
| 117 | explicit SwitchBuilder(BytecodeArrayBuilder* builder, int number_of_cases) |
| 118 | : BreakableControlFlowBuilder(builder), |
| 119 | case_sites_(builder->zone()) { |
| 120 | case_sites_.resize(number_of_cases); |
| 121 | } |
| 122 | ~SwitchBuilder(); |
| 123 | |
| 124 | // This method should be called by the SwitchBuilder owner when the case |
| 125 | // statement with |index| is emitted to update the case jump site. |
| 126 | void SetCaseTarget(int index); |
| 127 | |
| 128 | // This method is called when visiting case comparison operation for |index|. |
| 129 | // Inserts a JumpIfTrue to a unbound label that is patched when the |
| 130 | // corresponding SetCaseTarget is called. |
| 131 | void Case(int index) { EmitJumpIfTrue(&case_sites_, index); } |
| 132 | |
| 133 | // This method is called when all cases comparisons have been emitted if there |
| 134 | // is a default case statement. Inserts a Jump to a unbound label that is |
| 135 | // patched when the corresponding SetCaseTarget is called. |
| 136 | void DefaultAt(int index) { EmitJump(&case_sites_, index); } |
| 137 | |
| 138 | private: |
| 139 | // Unbound labels that identify jumps for case statements in the code. |
| 140 | ZoneVector<BytecodeLabel> case_sites_; |
| 141 | }; |
| 142 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 143 | |
| 144 | // A class to help with co-ordinating control flow in try-catch statements. |
| 145 | class TryCatchBuilder final : public ControlFlowBuilder { |
| 146 | public: |
| 147 | explicit TryCatchBuilder(BytecodeArrayBuilder* builder) |
| 148 | : ControlFlowBuilder(builder), handler_id_(builder->NewHandlerEntry()) {} |
| 149 | |
| 150 | void BeginTry(Register context); |
| 151 | void EndTry(); |
| 152 | void EndCatch(); |
| 153 | |
| 154 | private: |
| 155 | int handler_id_; |
| 156 | BytecodeLabel handler_; |
| 157 | BytecodeLabel exit_; |
| 158 | }; |
| 159 | |
| 160 | |
| 161 | // A class to help with co-ordinating control flow in try-finally statements. |
| 162 | class TryFinallyBuilder final : public ControlFlowBuilder { |
| 163 | public: |
| 164 | explicit TryFinallyBuilder(BytecodeArrayBuilder* builder, bool will_catch) |
| 165 | : ControlFlowBuilder(builder), |
| 166 | handler_id_(builder->NewHandlerEntry()), |
| 167 | finalization_sites_(builder->zone()), |
| 168 | will_catch_(will_catch) {} |
| 169 | |
| 170 | void BeginTry(Register context); |
| 171 | void LeaveTry(); |
| 172 | void EndTry(); |
| 173 | void BeginHandler(); |
| 174 | void BeginFinally(); |
| 175 | void EndFinally(); |
| 176 | |
| 177 | private: |
| 178 | int handler_id_; |
| 179 | BytecodeLabel handler_; |
| 180 | |
| 181 | // Unbound labels that identify jumps to the finally block in the code. |
| 182 | ZoneVector<BytecodeLabel> finalization_sites_; |
| 183 | |
| 184 | // Conservative prediction of whether exceptions thrown into the handler for |
| 185 | // this finally block will be caught. Note that such a prediction depends on |
| 186 | // whether this try-finally is nested inside a surrounding try-catch. |
| 187 | bool will_catch_; |
| 188 | }; |
| 189 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 190 | } // namespace interpreter |
| 191 | } // namespace internal |
| 192 | } // namespace v8 |
| 193 | |
| 194 | #endif // V8_INTERPRETER_CONTROL_FLOW_BUILDERS_H_ |