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_IA32_REGEXP_MACRO_ASSEMBLER_IA32_H_
6 #define V8_IA32_REGEXP_MACRO_ASSEMBLER_IA32_H_
7 
8 #include "src/ia32/assembler-ia32.h"
9 #include "src/ia32/assembler-ia32-inl.h"
10 #include "src/macro-assembler.h"
11 
12 namespace v8 {
13 namespace internal {
14 
15 #ifndef V8_INTERPRETED_REGEXP
16 class RegExpMacroAssemblerIA32: public NativeRegExpMacroAssembler {
17  public:
18   RegExpMacroAssemblerIA32(Mode mode, int registers_to_save, Zone* zone);
19   virtual ~RegExpMacroAssemblerIA32();
20   virtual int stack_limit_slack();
21   virtual void AdvanceCurrentPosition(int by);
22   virtual void AdvanceRegister(int reg, int by);
23   virtual void Backtrack();
24   virtual void Bind(Label* label);
25   virtual void CheckAtStart(Label* on_at_start);
26   virtual void CheckCharacter(uint32_t c, Label* on_equal);
27   virtual void CheckCharacterAfterAnd(uint32_t c,
28                                       uint32_t mask,
29                                       Label* on_equal);
30   virtual void CheckCharacterGT(uc16 limit, Label* on_greater);
31   virtual void CheckCharacterLT(uc16 limit, Label* on_less);
32   // A "greedy loop" is a loop that is both greedy and with a simple
33   // body. It has a particularly simple implementation.
34   virtual void CheckGreedyLoop(Label* on_tos_equals_current_position);
35   virtual void CheckNotAtStart(Label* on_not_at_start);
36   virtual void CheckNotBackReference(int start_reg, Label* on_no_match);
37   virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
38                                                Label* on_no_match);
39   virtual void CheckNotCharacter(uint32_t c, Label* on_not_equal);
40   virtual void CheckNotCharacterAfterAnd(uint32_t c,
41                                          uint32_t mask,
42                                          Label* on_not_equal);
43   virtual void CheckNotCharacterAfterMinusAnd(uc16 c,
44                                               uc16 minus,
45                                               uc16 mask,
46                                               Label* on_not_equal);
47   virtual void CheckCharacterInRange(uc16 from,
48                                      uc16 to,
49                                      Label* on_in_range);
50   virtual void CheckCharacterNotInRange(uc16 from,
51                                         uc16 to,
52                                         Label* on_not_in_range);
53   virtual void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set);
54 
55   // Checks whether the given offset from the current position is before
56   // the end of the string.
57   virtual void CheckPosition(int cp_offset, Label* on_outside_input);
58   virtual bool CheckSpecialCharacterClass(uc16 type, Label* on_no_match);
59   virtual void Fail();
60   virtual Handle<HeapObject> GetCode(Handle<String> source);
61   virtual void GoTo(Label* label);
62   virtual void IfRegisterGE(int reg, int comparand, Label* if_ge);
63   virtual void IfRegisterLT(int reg, int comparand, Label* if_lt);
64   virtual void IfRegisterEqPos(int reg, Label* if_eq);
65   virtual IrregexpImplementation Implementation();
66   virtual void LoadCurrentCharacter(int cp_offset,
67                                     Label* on_end_of_input,
68                                     bool check_bounds = true,
69                                     int characters = 1);
70   virtual void PopCurrentPosition();
71   virtual void PopRegister(int register_index);
72   virtual void PushBacktrack(Label* label);
73   virtual void PushCurrentPosition();
74   virtual void PushRegister(int register_index,
75                             StackCheckFlag check_stack_limit);
76   virtual void ReadCurrentPositionFromRegister(int reg);
77   virtual void ReadStackPointerFromRegister(int reg);
78   virtual void SetCurrentPositionFromEnd(int by);
79   virtual void SetRegister(int register_index, int to);
80   virtual bool Succeed();
81   virtual void WriteCurrentPositionToRegister(int reg, int cp_offset);
82   virtual void ClearRegisters(int reg_from, int reg_to);
83   virtual void WriteStackPointerToRegister(int reg);
84 
85   // Called from RegExp if the stack-guard is triggered.
86   // If the code object is relocated, the return address is fixed before
87   // returning.
88   static int CheckStackGuardState(Address* return_address,
89                                   Code* re_code,
90                                   Address re_frame);
91 
92  private:
93   // Offsets from ebp of function parameters and stored registers.
94   static const int kFramePointer = 0;
95   // Above the frame pointer - function parameters and return address.
96   static const int kReturn_eip = kFramePointer + kPointerSize;
97   static const int kFrameAlign = kReturn_eip + kPointerSize;
98   // Parameters.
99   static const int kInputString = kFrameAlign;
100   static const int kStartIndex = kInputString + kPointerSize;
101   static const int kInputStart = kStartIndex + kPointerSize;
102   static const int kInputEnd = kInputStart + kPointerSize;
103   static const int kRegisterOutput = kInputEnd + kPointerSize;
104   // For the case of global regular expression, we have room to store at least
105   // one set of capture results.  For the case of non-global regexp, we ignore
106   // this value.
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   // Below the frame pointer - local stack variables.
112   // When adding local variables remember to push space for them in
113   // the frame in GetCode.
114   static const int kBackup_esi = kFramePointer - kPointerSize;
115   static const int kBackup_edi = kBackup_esi - kPointerSize;
116   static const int kBackup_ebx = kBackup_edi - kPointerSize;
117   static const int kSuccessfulCaptures = kBackup_ebx - kPointerSize;
118   static const int kInputStartMinusOne = kSuccessfulCaptures - kPointerSize;
119   // First register address. Following registers are below it on the stack.
120   static const int kRegisterZero = kInputStartMinusOne - kPointerSize;
121 
122   // Initial size of code buffer.
123   static const size_t kRegExpCodeSize = 1024;
124 
125   // Load a number of characters at the given offset from the
126   // current position, into the current-character register.
127   void LoadCurrentCharacterUnchecked(int cp_offset, int character_count);
128 
129   // Check whether preemption has been requested.
130   void CheckPreemption();
131 
132   // Check whether we are exceeding the stack limit on the backtrack stack.
133   void CheckStackLimit();
134 
135   // Generate a call to CheckStackGuardState.
136   void CallCheckStackGuardState(Register scratch);
137 
138   // The ebp-relative location of a regexp register.
139   Operand register_location(int register_index);
140 
141   // The register containing the current character after LoadCurrentCharacter.
current_character()142   inline Register current_character() { return edx; }
143 
144   // The register containing the backtrack stack top. Provides a meaningful
145   // name to the register.
backtrack_stackpointer()146   inline Register backtrack_stackpointer() { return ecx; }
147 
148   // Byte size of chars in the string to match (decided by the Mode argument)
char_size()149   inline int char_size() { return static_cast<int>(mode_); }
150 
151   // Equivalent to a conditional branch to the label, unless the label
152   // is NULL, in which case it is a conditional Backtrack.
153   void BranchOrBacktrack(Condition condition, Label* to);
154 
155   // Call and return internally in the generated code in a way that
156   // is GC-safe (i.e., doesn't leave absolute code addresses on the stack)
157   inline void SafeCall(Label* to);
158   inline void SafeReturn();
159   inline void SafeCallTarget(Label* name);
160 
161   // Pushes the value of a register on the backtrack stack. Decrements the
162   // stack pointer (ecx) by a word size and stores the register's value there.
163   inline void Push(Register source);
164 
165   // Pushes a value on the backtrack stack. Decrements the stack pointer (ecx)
166   // by a word size and stores the value there.
167   inline void Push(Immediate value);
168 
169   // Pops a value from the backtrack stack. Reads the word at the stack pointer
170   // (ecx) and increments it by a word size.
171   inline void Pop(Register target);
172 
isolate()173   Isolate* isolate() const { return masm_->isolate(); }
174 
175   MacroAssembler* masm_;
176 
177   // Which mode to generate code for (LATIN1 or UC16).
178   Mode mode_;
179 
180   // One greater than maximal register index actually used.
181   int num_registers_;
182 
183   // Number of registers to output at the end (the saved registers
184   // are always 0..num_saved_registers_-1)
185   int num_saved_registers_;
186 
187   // Labels used internally.
188   Label entry_label_;
189   Label start_label_;
190   Label success_label_;
191   Label backtrack_label_;
192   Label exit_label_;
193   Label check_preempt_label_;
194   Label stack_overflow_label_;
195 };
196 #endif  // V8_INTERPRETED_REGEXP
197 
198 }}  // namespace v8::internal
199 
200 #endif  // V8_IA32_REGEXP_MACRO_ASSEMBLER_IA32_H_
201