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27
28#ifndef V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
29#define V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
30
31#include "arm/assembler-arm.h"
32#include "arm/assembler-arm-inl.h"
33#include "macro-assembler.h"
34
35namespace v8 {
36namespace internal {
37
38
39#ifndef V8_INTERPRETED_REGEXP
40class RegExpMacroAssemblerARM: public NativeRegExpMacroAssembler {
41 public:
42  RegExpMacroAssemblerARM(Mode mode, int registers_to_save, Zone* zone);
43  virtual ~RegExpMacroAssemblerARM();
44  virtual int stack_limit_slack();
45  virtual void AdvanceCurrentPosition(int by);
46  virtual void AdvanceRegister(int reg, int by);
47  virtual void Backtrack();
48  virtual void Bind(Label* label);
49  virtual void CheckAtStart(Label* on_at_start);
50  virtual void CheckCharacter(unsigned c, Label* on_equal);
51  virtual void CheckCharacterAfterAnd(unsigned c,
52                                      unsigned mask,
53                                      Label* on_equal);
54  virtual void CheckCharacterGT(uc16 limit, Label* on_greater);
55  virtual void CheckCharacterLT(uc16 limit, Label* on_less);
56  // A "greedy loop" is a loop that is both greedy and with a simple
57  // body. It has a particularly simple implementation.
58  virtual void CheckGreedyLoop(Label* on_tos_equals_current_position);
59  virtual void CheckNotAtStart(Label* on_not_at_start);
60  virtual void CheckNotBackReference(int start_reg, Label* on_no_match);
61  virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
62                                               Label* on_no_match);
63  virtual void CheckNotCharacter(unsigned c, Label* on_not_equal);
64  virtual void CheckNotCharacterAfterAnd(unsigned c,
65                                         unsigned mask,
66                                         Label* on_not_equal);
67  virtual void CheckNotCharacterAfterMinusAnd(uc16 c,
68                                              uc16 minus,
69                                              uc16 mask,
70                                              Label* on_not_equal);
71  virtual void CheckCharacterInRange(uc16 from,
72                                     uc16 to,
73                                     Label* on_in_range);
74  virtual void CheckCharacterNotInRange(uc16 from,
75                                        uc16 to,
76                                        Label* on_not_in_range);
77  virtual void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set);
78
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 bool 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  virtual bool CanReadUnaligned();
110
111  // Called from RegExp if the stack-guard is triggered.
112  // If the code object is relocated, the return address is fixed before
113  // returning.
114  static int CheckStackGuardState(Address* return_address,
115                                  Code* re_code,
116                                  Address re_frame);
117
118 private:
119  // Offsets from frame_pointer() of function parameters and stored registers.
120  static const int kFramePointer = 0;
121
122  // Above the frame pointer - Stored registers and stack passed parameters.
123  // Register 4..11.
124  static const int kStoredRegisters = kFramePointer;
125  // Return address (stored from link register, read into pc on return).
126  static const int kReturnAddress = kStoredRegisters + 8 * kPointerSize;
127  static const int kSecondaryReturnAddress = kReturnAddress + kPointerSize;
128  // Stack parameters placed by caller.
129  static const int kRegisterOutput = kSecondaryReturnAddress + kPointerSize;
130  static const int kNumOutputRegisters = kRegisterOutput + kPointerSize;
131  static const int kStackHighEnd = kNumOutputRegisters + kPointerSize;
132  static const int kDirectCall = kStackHighEnd + kPointerSize;
133  static const int kIsolate = kDirectCall + kPointerSize;
134
135  // Below the frame pointer.
136  // Register parameters stored by setup code.
137  static const int kInputEnd = kFramePointer - kPointerSize;
138  static const int kInputStart = kInputEnd - kPointerSize;
139  static const int kStartIndex = kInputStart - kPointerSize;
140  static const int kInputString = kStartIndex - kPointerSize;
141  // When adding local variables remember to push space for them in
142  // the frame in GetCode.
143  static const int kSuccessfulCaptures = kInputString - kPointerSize;
144  static const int kInputStartMinusOne = kSuccessfulCaptures - kPointerSize;
145  // First register address. Following registers are below it on the stack.
146  static const int kRegisterZero = kInputStartMinusOne - kPointerSize;
147
148  // Initial size of code buffer.
149  static const size_t kRegExpCodeSize = 1024;
150
151  static const int kBacktrackConstantPoolSize = 4;
152
153  // Load a number of characters at the given offset from the
154  // current position, into the current-character register.
155  void LoadCurrentCharacterUnchecked(int cp_offset, int character_count);
156
157  // Check whether preemption has been requested.
158  void CheckPreemption();
159
160  // Check whether we are exceeding the stack limit on the backtrack stack.
161  void CheckStackLimit();
162
163  void EmitBacktrackConstantPool();
164  int GetBacktrackConstantPoolEntry();
165
166
167  // Generate a call to CheckStackGuardState.
168  void CallCheckStackGuardState(Register scratch);
169
170  // The ebp-relative location of a regexp register.
171  MemOperand register_location(int register_index);
172
173  // Register holding the current input position as negative offset from
174  // the end of the string.
175  inline Register current_input_offset() { return r6; }
176
177  // The register containing the current character after LoadCurrentCharacter.
178  inline Register current_character() { return r7; }
179
180  // Register holding address of the end of the input string.
181  inline Register end_of_input_address() { return r10; }
182
183  // Register holding the frame address. Local variables, parameters and
184  // regexp registers are addressed relative to this.
185  inline Register frame_pointer() { return fp; }
186
187  // The register containing the backtrack stack top. Provides a meaningful
188  // name to the register.
189  inline Register backtrack_stackpointer() { return r8; }
190
191  // Register holding pointer to the current code object.
192  inline Register code_pointer() { return r5; }
193
194  // Byte size of chars in the string to match (decided by the Mode argument)
195  inline int char_size() { return static_cast<int>(mode_); }
196
197  // Equivalent to a conditional branch to the label, unless the label
198  // is NULL, in which case it is a conditional Backtrack.
199  void BranchOrBacktrack(Condition condition, Label* to);
200
201  // Call and return internally in the generated code in a way that
202  // is GC-safe (i.e., doesn't leave absolute code addresses on the stack)
203  inline void SafeCall(Label* to, Condition cond = al);
204  inline void SafeReturn();
205  inline void SafeCallTarget(Label* name);
206
207  // Pushes the value of a register on the backtrack stack. Decrements the
208  // stack pointer by a word size and stores the register's value there.
209  inline void Push(Register source);
210
211  // Pops a value from the backtrack stack. Reads the word at the stack pointer
212  // and increments it by a word size.
213  inline void Pop(Register target);
214
215  // Calls a C function and cleans up the frame alignment done by
216  // by FrameAlign. The called function *is* allowed to trigger a garbage
217  // collection, but may not take more than four arguments (no arguments
218  // passed on the stack), and the first argument will be a pointer to the
219  // return address.
220  inline void CallCFunctionUsingStub(ExternalReference function,
221                                     int num_arguments);
222
223  Isolate* isolate() const { return masm_->isolate(); }
224
225  MacroAssembler* masm_;
226
227  // Which mode to generate code for (ASCII or UC16).
228  Mode mode_;
229
230  // One greater than maximal register index actually used.
231  int num_registers_;
232
233  // Number of registers to output at the end (the saved registers
234  // are always 0..num_saved_registers_-1)
235  int num_saved_registers_;
236
237  // Manage a small pre-allocated pool for writing label targets
238  // to for pushing backtrack addresses.
239  int backtrack_constant_pool_offset_;
240  int backtrack_constant_pool_capacity_;
241
242  // Labels used internally.
243  Label entry_label_;
244  Label start_label_;
245  Label success_label_;
246  Label backtrack_label_;
247  Label exit_label_;
248  Label check_preempt_label_;
249  Label stack_overflow_label_;
250};
251
252#endif  // V8_INTERPRETED_REGEXP
253
254
255}}  // namespace v8::internal
256
257#endif  // V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
258