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_REGEXP_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_
6 #define V8_REGEXP_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_
7 
8 #include "src/regexp/regexp-macro-assembler.h"
9 
10 namespace v8 {
11 namespace internal {
12 
13 #ifdef V8_INTERPRETED_REGEXP
14 
15 // A light-weight assembler for the Irregexp byte code.
16 class RegExpMacroAssemblerIrregexp: public RegExpMacroAssembler {
17  public:
18   // Create an assembler. Instructions and relocation information are emitted
19   // into a buffer, with the instructions starting from the beginning and the
20   // relocation information starting from the end of the buffer. See CodeDesc
21   // for a detailed comment on the layout (globals.h).
22   //
23   // If the provided buffer is NULL, the assembler allocates and grows its own
24   // buffer, and buffer_size determines the initial buffer size. The buffer is
25   // owned by the assembler and deallocated upon destruction of the assembler.
26   //
27   // If the provided buffer is not NULL, the assembler uses the provided buffer
28   // for code generation and assumes its size to be buffer_size. If the buffer
29   // is too small, a fatal error occurs. No deallocation of the buffer is done
30   // upon destruction of the assembler.
31   RegExpMacroAssemblerIrregexp(Isolate* isolate, Vector<byte> buffer,
32                                Zone* zone);
33   virtual ~RegExpMacroAssemblerIrregexp();
34   // The byte-code interpreter checks on each push anyway.
stack_limit_slack()35   virtual int stack_limit_slack() { return 1; }
CanReadUnaligned()36   virtual bool CanReadUnaligned() { return false; }
37   virtual void Bind(Label* label);
38   virtual void AdvanceCurrentPosition(int by);  // Signed cp change.
39   virtual void PopCurrentPosition();
40   virtual void PushCurrentPosition();
41   virtual void Backtrack();
42   virtual void GoTo(Label* label);
43   virtual void PushBacktrack(Label* label);
44   virtual bool Succeed();
45   virtual void Fail();
46   virtual void PopRegister(int register_index);
47   virtual void PushRegister(int register_index,
48                             StackCheckFlag check_stack_limit);
49   virtual void AdvanceRegister(int reg, int by);  // r[reg] += by.
50   virtual void SetCurrentPositionFromEnd(int by);
51   virtual void SetRegister(int register_index, int to);
52   virtual void WriteCurrentPositionToRegister(int reg, int cp_offset);
53   virtual void ClearRegisters(int reg_from, int reg_to);
54   virtual void ReadCurrentPositionFromRegister(int reg);
55   virtual void WriteStackPointerToRegister(int reg);
56   virtual void ReadStackPointerFromRegister(int reg);
57   virtual void LoadCurrentCharacter(int cp_offset,
58                                     Label* on_end_of_input,
59                                     bool check_bounds = true,
60                                     int characters = 1);
61   virtual void CheckCharacter(unsigned c, Label* on_equal);
62   virtual void CheckCharacterAfterAnd(unsigned c,
63                                       unsigned mask,
64                                       Label* on_equal);
65   virtual void CheckCharacterGT(uc16 limit, Label* on_greater);
66   virtual void CheckCharacterLT(uc16 limit, Label* on_less);
67   virtual void CheckGreedyLoop(Label* on_tos_equals_current_position);
68   virtual void CheckAtStart(Label* on_at_start);
69   virtual void CheckNotAtStart(int cp_offset, Label* on_not_at_start);
70   virtual void CheckNotCharacter(unsigned c, Label* on_not_equal);
71   virtual void CheckNotCharacterAfterAnd(unsigned c,
72                                          unsigned mask,
73                                          Label* on_not_equal);
74   virtual void CheckNotCharacterAfterMinusAnd(uc16 c,
75                                               uc16 minus,
76                                               uc16 mask,
77                                               Label* on_not_equal);
78   virtual void CheckCharacterInRange(uc16 from,
79                                      uc16 to,
80                                      Label* on_in_range);
81   virtual void CheckCharacterNotInRange(uc16 from,
82                                         uc16 to,
83                                         Label* on_not_in_range);
84   virtual void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set);
85   virtual void CheckNotBackReference(int start_reg, bool read_backward,
86                                      Label* on_no_match);
87   virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
88                                                bool read_backward,
89                                                Label* on_no_match);
90   virtual void IfRegisterLT(int register_index, int comparand, Label* if_lt);
91   virtual void IfRegisterGE(int register_index, int comparand, Label* if_ge);
92   virtual void IfRegisterEqPos(int register_index, Label* if_eq);
93 
94   virtual IrregexpImplementation Implementation();
95   virtual Handle<HeapObject> GetCode(Handle<String> source);
96 
97  private:
98   void Expand();
99   // Code and bitmap emission.
100   inline void EmitOrLink(Label* label);
101   inline void Emit32(uint32_t x);
102   inline void Emit16(uint32_t x);
103   inline void Emit8(uint32_t x);
104   inline void Emit(uint32_t bc, uint32_t arg);
105   // Bytecode buffer.
106   int length();
107   void Copy(Address a);
108 
109   // The buffer into which code and relocation info are generated.
110   Vector<byte> buffer_;
111   // The program counter.
112   int pc_;
113   // True if the assembler owns the buffer, false if buffer is external.
114   bool own_buffer_;
115   Label backtrack_;
116 
117   int advance_current_start_;
118   int advance_current_offset_;
119   int advance_current_end_;
120 
121   Isolate* isolate_;
122 
123   static const int kInvalidPC = -1;
124 
125   DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpMacroAssemblerIrregexp);
126 };
127 
128 #endif  // V8_INTERPRETED_REGEXP
129 
130 }  // namespace internal
131 }  // namespace v8
132 
133 #endif  // V8_REGEXP_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_
134