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27
28#ifndef V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
29#define V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
30
31namespace v8 {
32namespace internal {
33
34
35#ifdef V8_INTERPRETED_REGEXP
36class RegExpMacroAssemblerARM: public RegExpMacroAssembler {
37 public:
38  RegExpMacroAssemblerARM();
39  virtual ~RegExpMacroAssemblerARM();
40};
41
42#else  // V8_INTERPRETED_REGEXP
43class RegExpMacroAssemblerARM: public NativeRegExpMacroAssembler {
44 public:
45  RegExpMacroAssemblerARM(Mode mode, int registers_to_save);
46  virtual ~RegExpMacroAssemblerARM();
47  virtual int stack_limit_slack();
48  virtual void AdvanceCurrentPosition(int by);
49  virtual void AdvanceRegister(int reg, int by);
50  virtual void Backtrack();
51  virtual void Bind(Label* label);
52  virtual void CheckAtStart(Label* on_at_start);
53  virtual void CheckCharacter(unsigned c, Label* on_equal);
54  virtual void CheckCharacterAfterAnd(unsigned c,
55                                      unsigned mask,
56                                      Label* on_equal);
57  virtual void CheckCharacterGT(uc16 limit, Label* on_greater);
58  virtual void CheckCharacterLT(uc16 limit, Label* on_less);
59  virtual void CheckCharacters(Vector<const uc16> str,
60                               int cp_offset,
61                               Label* on_failure,
62                               bool check_end_of_string);
63  // A "greedy loop" is a loop that is both greedy and with a simple
64  // body. It has a particularly simple implementation.
65  virtual void CheckGreedyLoop(Label* on_tos_equals_current_position);
66  virtual void CheckNotAtStart(Label* on_not_at_start);
67  virtual void CheckNotBackReference(int start_reg, Label* on_no_match);
68  virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
69                                               Label* on_no_match);
70  virtual void CheckNotRegistersEqual(int reg1, int reg2, Label* on_not_equal);
71  virtual void CheckNotCharacter(unsigned c, Label* on_not_equal);
72  virtual void CheckNotCharacterAfterAnd(unsigned c,
73                                         unsigned mask,
74                                         Label* on_not_equal);
75  virtual void CheckNotCharacterAfterMinusAnd(uc16 c,
76                                              uc16 minus,
77                                              uc16 mask,
78                                              Label* on_not_equal);
79  // Checks whether the given offset from the current position is before
80  // the end of the string.
81  virtual void CheckPosition(int cp_offset, Label* on_outside_input);
82  virtual bool CheckSpecialCharacterClass(uc16 type,
83                                          Label* on_no_match);
84  virtual void Fail();
85  virtual Handle<HeapObject> GetCode(Handle<String> source);
86  virtual void GoTo(Label* label);
87  virtual void IfRegisterGE(int reg, int comparand, Label* if_ge);
88  virtual void IfRegisterLT(int reg, int comparand, Label* if_lt);
89  virtual void IfRegisterEqPos(int reg, Label* if_eq);
90  virtual IrregexpImplementation Implementation();
91  virtual void LoadCurrentCharacter(int cp_offset,
92                                    Label* on_end_of_input,
93                                    bool check_bounds = true,
94                                    int characters = 1);
95  virtual void PopCurrentPosition();
96  virtual void PopRegister(int register_index);
97  virtual void PushBacktrack(Label* label);
98  virtual void PushCurrentPosition();
99  virtual void PushRegister(int register_index,
100                            StackCheckFlag check_stack_limit);
101  virtual void ReadCurrentPositionFromRegister(int reg);
102  virtual void ReadStackPointerFromRegister(int reg);
103  virtual void SetCurrentPositionFromEnd(int by);
104  virtual void SetRegister(int register_index, int to);
105  virtual void Succeed();
106  virtual void WriteCurrentPositionToRegister(int reg, int cp_offset);
107  virtual void ClearRegisters(int reg_from, int reg_to);
108  virtual void WriteStackPointerToRegister(int reg);
109
110  // Called from RegExp if the stack-guard is triggered.
111  // If the code object is relocated, the return address is fixed before
112  // returning.
113  static int CheckStackGuardState(Address* return_address,
114                                  Code* re_code,
115                                  Address re_frame);
116 private:
117  // Offsets from frame_pointer() of function parameters and stored registers.
118  static const int kFramePointer = 0;
119
120  // Above the frame pointer - Stored registers and stack passed parameters.
121  // Register 4..11.
122  static const int kStoredRegisters = kFramePointer;
123  // Return address (stored from link register, read into pc on return).
124  static const int kReturnAddress = kStoredRegisters + 8 * kPointerSize;
125  static const int kSecondaryReturnAddress = kReturnAddress + kPointerSize;
126  // Stack parameters placed by caller.
127  static const int kRegisterOutput = kSecondaryReturnAddress + kPointerSize;
128  static const int kStackHighEnd = kRegisterOutput + kPointerSize;
129  static const int kDirectCall = kStackHighEnd + kPointerSize;
130  static const int kIsolate = kDirectCall + kPointerSize;
131
132  // Below the frame pointer.
133  // Register parameters stored by setup code.
134  static const int kInputEnd = kFramePointer - kPointerSize;
135  static const int kInputStart = kInputEnd - kPointerSize;
136  static const int kStartIndex = kInputStart - kPointerSize;
137  static const int kInputString = kStartIndex - kPointerSize;
138  // When adding local variables remember to push space for them in
139  // the frame in GetCode.
140  static const int kInputStartMinusOne = kInputString - kPointerSize;
141  static const int kAtStart = kInputStartMinusOne - kPointerSize;
142  // First register address. Following registers are below it on the stack.
143  static const int kRegisterZero = kAtStart - kPointerSize;
144
145  // Initial size of code buffer.
146  static const size_t kRegExpCodeSize = 1024;
147
148  static const int kBacktrackConstantPoolSize = 4;
149
150  // Load a number of characters at the given offset from the
151  // current position, into the current-character register.
152  void LoadCurrentCharacterUnchecked(int cp_offset, int character_count);
153
154  // Check whether preemption has been requested.
155  void CheckPreemption();
156
157  // Check whether we are exceeding the stack limit on the backtrack stack.
158  void CheckStackLimit();
159
160  void EmitBacktrackConstantPool();
161  int GetBacktrackConstantPoolEntry();
162
163
164  // Generate a call to CheckStackGuardState.
165  void CallCheckStackGuardState(Register scratch);
166
167  // The ebp-relative location of a regexp register.
168  MemOperand register_location(int register_index);
169
170  // Register holding the current input position as negative offset from
171  // the end of the string.
172  inline Register current_input_offset() { return r6; }
173
174  // The register containing the current character after LoadCurrentCharacter.
175  inline Register current_character() { return r7; }
176
177  // Register holding address of the end of the input string.
178  inline Register end_of_input_address() { return r10; }
179
180  // Register holding the frame address. Local variables, parameters and
181  // regexp registers are addressed relative to this.
182  inline Register frame_pointer() { return fp; }
183
184  // The register containing the backtrack stack top. Provides a meaningful
185  // name to the register.
186  inline Register backtrack_stackpointer() { return r8; }
187
188  // Register holding pointer to the current code object.
189  inline Register code_pointer() { return r5; }
190
191  // Byte size of chars in the string to match (decided by the Mode argument)
192  inline int char_size() { return static_cast<int>(mode_); }
193
194  // Equivalent to a conditional branch to the label, unless the label
195  // is NULL, in which case it is a conditional Backtrack.
196  void BranchOrBacktrack(Condition condition, Label* to);
197
198  // Call and return internally in the generated code in a way that
199  // is GC-safe (i.e., doesn't leave absolute code addresses on the stack)
200  inline void SafeCall(Label* to, Condition cond = al);
201  inline void SafeReturn();
202  inline void SafeCallTarget(Label* name);
203
204  // Pushes the value of a register on the backtrack stack. Decrements the
205  // stack pointer by a word size and stores the register's value there.
206  inline void Push(Register source);
207
208  // Pops a value from the backtrack stack. Reads the word at the stack pointer
209  // and increments it by a word size.
210  inline void Pop(Register target);
211
212  // Calls a C function and cleans up the frame alignment done by
213  // by FrameAlign. The called function *is* allowed to trigger a garbage
214  // collection, but may not take more than four arguments (no arguments
215  // passed on the stack), and the first argument will be a pointer to the
216  // return address.
217  inline void CallCFunctionUsingStub(ExternalReference function,
218                                     int num_arguments);
219
220
221  MacroAssembler* masm_;
222
223  // Which mode to generate code for (ASCII or UC16).
224  Mode mode_;
225
226  // One greater than maximal register index actually used.
227  int num_registers_;
228
229  // Number of registers to output at the end (the saved registers
230  // are always 0..num_saved_registers_-1)
231  int num_saved_registers_;
232
233  // Manage a small pre-allocated pool for writing label targets
234  // to for pushing backtrack addresses.
235  int backtrack_constant_pool_offset_;
236  int backtrack_constant_pool_capacity_;
237
238  // Labels used internally.
239  Label entry_label_;
240  Label start_label_;
241  Label success_label_;
242  Label backtrack_label_;
243  Label exit_label_;
244  Label check_preempt_label_;
245  Label stack_overflow_label_;
246};
247
248#endif  // V8_INTERPRETED_REGEXP
249
250
251}}  // namespace v8::internal
252
253#endif  // V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
254