1// Copyright 2012 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_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
6#define V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
7
8#include "src/arm/assembler-arm.h"
9#include "src/arm/assembler-arm-inl.h"
10#include "src/macro-assembler.h"
11
12namespace v8 {
13namespace internal {
14
15
16#ifndef V8_INTERPRETED_REGEXP
17class RegExpMacroAssemblerARM: public NativeRegExpMacroAssembler {
18 public:
19  RegExpMacroAssemblerARM(Mode mode, int registers_to_save, Zone* zone);
20  virtual ~RegExpMacroAssemblerARM();
21  virtual int stack_limit_slack();
22  virtual void AdvanceCurrentPosition(int by);
23  virtual void AdvanceRegister(int reg, int by);
24  virtual void Backtrack();
25  virtual void Bind(Label* label);
26  virtual void CheckAtStart(Label* on_at_start);
27  virtual void CheckCharacter(unsigned c, Label* on_equal);
28  virtual void CheckCharacterAfterAnd(unsigned c,
29                                      unsigned mask,
30                                      Label* on_equal);
31  virtual void CheckCharacterGT(uc16 limit, Label* on_greater);
32  virtual void CheckCharacterLT(uc16 limit, Label* on_less);
33  // A "greedy loop" is a loop that is both greedy and with a simple
34  // body. It has a particularly simple implementation.
35  virtual void CheckGreedyLoop(Label* on_tos_equals_current_position);
36  virtual void CheckNotAtStart(Label* on_not_at_start);
37  virtual void CheckNotBackReference(int start_reg, Label* on_no_match);
38  virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
39                                               Label* on_no_match);
40  virtual void CheckNotCharacter(unsigned c, Label* on_not_equal);
41  virtual void CheckNotCharacterAfterAnd(unsigned c,
42                                         unsigned mask,
43                                         Label* on_not_equal);
44  virtual void CheckNotCharacterAfterMinusAnd(uc16 c,
45                                              uc16 minus,
46                                              uc16 mask,
47                                              Label* on_not_equal);
48  virtual void CheckCharacterInRange(uc16 from,
49                                     uc16 to,
50                                     Label* on_in_range);
51  virtual void CheckCharacterNotInRange(uc16 from,
52                                        uc16 to,
53                                        Label* on_not_in_range);
54  virtual void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set);
55
56  // Checks whether the given offset from the current position is before
57  // the end of the string.
58  virtual void CheckPosition(int cp_offset, Label* on_outside_input);
59  virtual bool CheckSpecialCharacterClass(uc16 type,
60                                          Label* on_no_match);
61  virtual void Fail();
62  virtual Handle<HeapObject> GetCode(Handle<String> source);
63  virtual void GoTo(Label* label);
64  virtual void IfRegisterGE(int reg, int comparand, Label* if_ge);
65  virtual void IfRegisterLT(int reg, int comparand, Label* if_lt);
66  virtual void IfRegisterEqPos(int reg, Label* if_eq);
67  virtual IrregexpImplementation Implementation();
68  virtual void LoadCurrentCharacter(int cp_offset,
69                                    Label* on_end_of_input,
70                                    bool check_bounds = true,
71                                    int characters = 1);
72  virtual void PopCurrentPosition();
73  virtual void PopRegister(int register_index);
74  virtual void PushBacktrack(Label* label);
75  virtual void PushCurrentPosition();
76  virtual void PushRegister(int register_index,
77                            StackCheckFlag check_stack_limit);
78  virtual void ReadCurrentPositionFromRegister(int reg);
79  virtual void ReadStackPointerFromRegister(int reg);
80  virtual void SetCurrentPositionFromEnd(int by);
81  virtual void SetRegister(int register_index, int to);
82  virtual bool Succeed();
83  virtual void WriteCurrentPositionToRegister(int reg, int cp_offset);
84  virtual void ClearRegisters(int reg_from, int reg_to);
85  virtual void WriteStackPointerToRegister(int reg);
86  virtual bool CanReadUnaligned();
87
88  // Called from RegExp if the stack-guard is triggered.
89  // If the code object is relocated, the return address is fixed before
90  // returning.
91  static int CheckStackGuardState(Address* return_address,
92                                  Code* re_code,
93                                  Address re_frame);
94
95 private:
96  // Offsets from frame_pointer() of function parameters and stored registers.
97  static const int kFramePointer = 0;
98
99  // Above the frame pointer - Stored registers and stack passed parameters.
100  // Register 4..11.
101  static const int kStoredRegisters = kFramePointer;
102  // Return address (stored from link register, read into pc on return).
103  static const int kReturnAddress = kStoredRegisters + 8 * kPointerSize;
104  static const int kSecondaryReturnAddress = kReturnAddress + kPointerSize;
105  // Stack parameters placed by caller.
106  static const int kRegisterOutput = kSecondaryReturnAddress + kPointerSize;
107  static const int kNumOutputRegisters = kRegisterOutput + kPointerSize;
108  static const int kStackHighEnd = kNumOutputRegisters + kPointerSize;
109  static const int kDirectCall = kStackHighEnd + kPointerSize;
110  static const int kIsolate = kDirectCall + kPointerSize;
111
112  // Below the frame pointer.
113  // Register parameters stored by setup code.
114  static const int kInputEnd = kFramePointer - kPointerSize;
115  static const int kInputStart = kInputEnd - kPointerSize;
116  static const int kStartIndex = kInputStart - kPointerSize;
117  static const int kInputString = kStartIndex - kPointerSize;
118  // When adding local variables remember to push space for them in
119  // the frame in GetCode.
120  static const int kSuccessfulCaptures = kInputString - kPointerSize;
121  static const int kInputStartMinusOne = kSuccessfulCaptures - kPointerSize;
122  // First register address. Following registers are below it on the stack.
123  static const int kRegisterZero = kInputStartMinusOne - kPointerSize;
124
125  // Initial size of code buffer.
126  static const size_t kRegExpCodeSize = 1024;
127
128  static const int kBacktrackConstantPoolSize = 4;
129
130  // Load a number of characters at the given offset from the
131  // current position, into the current-character register.
132  void LoadCurrentCharacterUnchecked(int cp_offset, int character_count);
133
134  // Check whether preemption has been requested.
135  void CheckPreemption();
136
137  // Check whether we are exceeding the stack limit on the backtrack stack.
138  void CheckStackLimit();
139
140
141  // Generate a call to CheckStackGuardState.
142  void CallCheckStackGuardState(Register scratch);
143
144  // The ebp-relative location of a regexp register.
145  MemOperand register_location(int register_index);
146
147  // Register holding the current input position as negative offset from
148  // the end of the string.
149  inline Register current_input_offset() { return r6; }
150
151  // The register containing the current character after LoadCurrentCharacter.
152  inline Register current_character() { return r7; }
153
154  // Register holding address of the end of the input string.
155  inline Register end_of_input_address() { return r10; }
156
157  // Register holding the frame address. Local variables, parameters and
158  // regexp registers are addressed relative to this.
159  inline Register frame_pointer() { return fp; }
160
161  // The register containing the backtrack stack top. Provides a meaningful
162  // name to the register.
163  inline Register backtrack_stackpointer() { return r8; }
164
165  // Register holding pointer to the current code object.
166  inline Register code_pointer() { return r5; }
167
168  // Byte size of chars in the string to match (decided by the Mode argument)
169  inline int char_size() { return static_cast<int>(mode_); }
170
171  // Equivalent to a conditional branch to the label, unless the label
172  // is NULL, in which case it is a conditional Backtrack.
173  void BranchOrBacktrack(Condition condition, Label* to);
174
175  // Call and return internally in the generated code in a way that
176  // is GC-safe (i.e., doesn't leave absolute code addresses on the stack)
177  inline void SafeCall(Label* to, Condition cond = al);
178  inline void SafeReturn();
179  inline void SafeCallTarget(Label* name);
180
181  // Pushes the value of a register on the backtrack stack. Decrements the
182  // stack pointer by a word size and stores the register's value there.
183  inline void Push(Register source);
184
185  // Pops a value from the backtrack stack. Reads the word at the stack pointer
186  // and increments it by a word size.
187  inline void Pop(Register target);
188
189  Isolate* isolate() const { return masm_->isolate(); }
190
191  MacroAssembler* masm_;
192
193  // Which mode to generate code for (Latin1 or UC16).
194  Mode mode_;
195
196  // One greater than maximal register index actually used.
197  int num_registers_;
198
199  // Number of registers to output at the end (the saved registers
200  // are always 0..num_saved_registers_-1)
201  int num_saved_registers_;
202
203  // Labels used internally.
204  Label entry_label_;
205  Label start_label_;
206  Label success_label_;
207  Label backtrack_label_;
208  Label exit_label_;
209  Label check_preempt_label_;
210  Label stack_overflow_label_;
211};
212
213#endif  // V8_INTERPRETED_REGEXP
214
215
216}}  // namespace v8::internal
217
218#endif  // V8_ARM_REGEXP_MACRO_ASSEMBLER_ARM_H_
219