1// Copyright 2021 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_LOONG64_REGEXP_MACRO_ASSEMBLER_LOONG64_H_
6#define V8_REGEXP_LOONG64_REGEXP_MACRO_ASSEMBLER_LOONG64_H_
7
8#include "src/codegen/macro-assembler.h"
9#include "src/regexp/regexp-macro-assembler.h"
10
11namespace v8 {
12namespace internal {
13
14class V8_EXPORT_PRIVATE RegExpMacroAssemblerLOONG64
15    : public NativeRegExpMacroAssembler {
16 public:
17  RegExpMacroAssemblerLOONG64(Isolate* isolate, Zone* zone, Mode mode,
18                              int registers_to_save);
19  ~RegExpMacroAssemblerLOONG64() override;
20  int stack_limit_slack() override;
21  void AdvanceCurrentPosition(int by) override;
22  void AdvanceRegister(int reg, int by) override;
23  void Backtrack() override;
24  void Bind(Label* label) override;
25  void CheckAtStart(int cp_offset, Label* on_at_start) override;
26  void CheckCharacter(uint32_t c, Label* on_equal) override;
27  void CheckCharacterAfterAnd(uint32_t c, uint32_t mask,
28                              Label* on_equal) override;
29  void CheckCharacterGT(base::uc16 limit, Label* on_greater) override;
30  void CheckCharacterLT(base::uc16 limit, Label* on_less) override;
31  // A "greedy loop" is a loop that is both greedy and with a simple
32  // body. It has a particularly simple implementation.
33  void CheckGreedyLoop(Label* on_tos_equals_current_position) override;
34  void CheckNotAtStart(int cp_offset, Label* on_not_at_start) override;
35  void CheckNotBackReference(int start_reg, bool read_backward,
36                             Label* on_no_match) override;
37  void CheckNotBackReferenceIgnoreCase(int start_reg, bool read_backward,
38                                       bool unicode,
39                                       Label* on_no_match) override;
40  void CheckNotCharacter(uint32_t c, Label* on_not_equal) override;
41  void CheckNotCharacterAfterAnd(uint32_t c, uint32_t mask,
42                                 Label* on_not_equal) override;
43  void CheckNotCharacterAfterMinusAnd(base::uc16 c, base::uc16 minus,
44                                      base::uc16 mask,
45                                      Label* on_not_equal) override;
46  void CheckCharacterInRange(base::uc16 from, base::uc16 to,
47                             Label* on_in_range) override;
48  void CheckCharacterNotInRange(base::uc16 from, base::uc16 to,
49                                Label* on_not_in_range) override;
50  bool CheckCharacterInRangeArray(const ZoneList<CharacterRange>* ranges,
51                                  Label* on_in_range) override;
52  bool CheckCharacterNotInRangeArray(const ZoneList<CharacterRange>* ranges,
53                                     Label* on_not_in_range) override;
54  void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set) override;
55
56  // Checks whether the given offset from the current position is before
57  // the end of the string.
58  void CheckPosition(int cp_offset, Label* on_outside_input) override;
59  bool CheckSpecialCharacterClass(StandardCharacterSet type,
60                                  Label* on_no_match) override;
61  void Fail() override;
62  Handle<HeapObject> GetCode(Handle<String> source) override;
63  void GoTo(Label* label) override;
64  void IfRegisterGE(int reg, int comparand, Label* if_ge) override;
65  void IfRegisterLT(int reg, int comparand, Label* if_lt) override;
66  void IfRegisterEqPos(int reg, Label* if_eq) override;
67  IrregexpImplementation Implementation() override;
68  void LoadCurrentCharacterUnchecked(int cp_offset,
69                                     int character_count) override;
70  void PopCurrentPosition() override;
71  void PopRegister(int register_index) override;
72  void PushBacktrack(Label* label) override;
73  void PushCurrentPosition() override;
74  void PushRegister(int register_index,
75                    StackCheckFlag check_stack_limit) override;
76  void ReadCurrentPositionFromRegister(int reg) override;
77  void ReadStackPointerFromRegister(int reg) override;
78  void SetCurrentPositionFromEnd(int by) override;
79  void SetRegister(int register_index, int to) override;
80  bool Succeed() override;
81  void WriteCurrentPositionToRegister(int reg, int cp_offset) override;
82  void ClearRegisters(int reg_from, int reg_to) override;
83  void WriteStackPointerToRegister(int reg) override;
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  // {raw_code} is an Address because this is called via ExternalReference.
89  static int64_t CheckStackGuardState(Address* return_address, Address raw_code,
90                                      Address re_frame);
91
92  void print_regexp_frame_constants();
93
94 private:
95  // Offsets from frame_pointer() of function parameters and stored registers.
96  static const int kFramePointer = 0;
97
98  // Above the frame pointer - Stored registers and stack passed parameters.
99  static const int kStoredRegisters = kFramePointer;
100  // Return address (stored from link register, read into pc on return).
101
102  // TODO(plind): This 9 - is 8 s-regs (s0..s7) plus fp.
103
104  static const int kReturnAddress = kStoredRegisters + 9 * kSystemPointerSize;
105  // Stack frame header.
106  static const int kStackFrameHeader = kReturnAddress;
107
108  // Below the frame pointer.
109  // Register parameters stored by setup code.
110  static const int kIsolate = kFramePointer - kSystemPointerSize;
111  static const int kDirectCall = kIsolate - kSystemPointerSize;
112  static const int kNumOutputRegisters = kDirectCall - kSystemPointerSize;
113  static const int kRegisterOutput = kNumOutputRegisters - kSystemPointerSize;
114  static const int kInputEnd = kRegisterOutput - kSystemPointerSize;
115  static const int kInputStart = kInputEnd - kSystemPointerSize;
116  static const int kStartIndex = kInputStart - kSystemPointerSize;
117  static const int kInputString = kStartIndex - kSystemPointerSize;
118  // When adding local variables remember to push space for them in
119  // the frame in GetCode.
120  static const int kSuccessfulCaptures = kInputString - kSystemPointerSize;
121  static const int kStringStartMinusOne =
122      kSuccessfulCaptures - kSystemPointerSize;
123  static const int kBacktrackCount = kStringStartMinusOne - kSystemPointerSize;
124  // Stores the initial value of the regexp stack pointer in a
125  // position-independent representation (in case the regexp stack grows and
126  // thus moves).
127  static const int kRegExpStackBasePointer =
128      kBacktrackCount - kSystemPointerSize;
129
130  // First register address. Following registers are below it on the stack.
131  static const int kRegisterZero = kRegExpStackBasePointer - kSystemPointerSize;
132
133  // Initial size of code buffer.
134  static const int kRegExpCodeSize = 1024;
135
136  void PushCallerSavedRegisters();
137  void PopCallerSavedRegisters();
138
139  // Check whether preemption has been requested.
140  void CheckPreemption();
141
142  // Check whether we are exceeding the stack limit on the backtrack stack.
143  void CheckStackLimit();
144
145  // Generate a call to CheckStackGuardState.
146  void CallCheckStackGuardState(Register scratch);
147  void CallIsCharacterInRangeArray(const ZoneList<CharacterRange>* ranges);
148
149  // The ebp-relative location of a regexp register.
150  MemOperand register_location(int register_index);
151
152  // Register holding the current input position as negative offset from
153  // the end of the string.
154  static constexpr Register current_input_offset() { return s2; }
155
156  // The register containing the current character after LoadCurrentCharacter.
157  static constexpr Register current_character() { return s5; }
158
159  // Register holding address of the end of the input string.
160  static constexpr Register end_of_input_address() { return s6; }
161
162  // Register holding the frame address. Local variables, parameters and
163  // regexp registers are addressed relative to this.
164  static constexpr Register frame_pointer() { return fp; }
165
166  // The register containing the backtrack stack top. Provides a meaningful
167  // name to the register.
168  static constexpr Register backtrack_stackpointer() { return s7; }
169
170  // Register holding pointer to the current code object.
171  static constexpr Register code_pointer() { return s1; }
172
173  // Byte size of chars in the string to match (decided by the Mode argument).
174  inline int char_size() { return static_cast<int>(mode_); }
175
176  // Equivalent to a conditional branch to the label, unless the label
177  // is nullptr, in which case it is a conditional Backtrack.
178  void BranchOrBacktrack(Label* to, Condition condition, Register rs,
179                         const Operand& rt);
180
181  // Call and return internally in the generated code in a way that
182  // is GC-safe (i.e., doesn't leave absolute code addresses on the stack)
183  inline void SafeCall(Label* to, Condition cond, Register rs,
184                       const Operand& rt);
185  inline void SafeReturn();
186  inline void SafeCallTarget(Label* name);
187
188  // Pushes the value of a register on the backtrack stack. Decrements the
189  // stack pointer by a word size and stores the register's value there.
190  inline void Push(Register source);
191
192  // Pops a value from the backtrack stack. Reads the word at the stack pointer
193  // and increments it by a word size.
194  inline void Pop(Register target);
195
196  void LoadRegExpStackPointerFromMemory(Register dst);
197  void StoreRegExpStackPointerToMemory(Register src, Register scratch);
198  void PushRegExpBasePointer(Register stack_pointer, Register scratch);
199  void PopRegExpBasePointer(Register stack_pointer_out, Register scratch);
200
201  Isolate* isolate() const { return masm_->isolate(); }
202
203  const std::unique_ptr<MacroAssembler> masm_;
204
205  const NoRootArrayScope no_root_array_scope_;
206
207  // Which mode to generate code for (Latin1 or UC16).
208  const Mode mode_;
209
210  // One greater than maximal register index actually used.
211  int num_registers_;
212
213  // Number of registers to output at the end (the saved registers
214  // are always 0..num_saved_registers_-1).
215  const int num_saved_registers_;
216
217  // Labels used internally.
218  Label entry_label_;
219  Label start_label_;
220  Label success_label_;
221  Label backtrack_label_;
222  Label exit_label_;
223  Label check_preempt_label_;
224  Label stack_overflow_label_;
225  Label internal_failure_label_;
226  Label fallback_label_;
227};
228
229}  // namespace internal
230}  // namespace v8
231
232#endif  // V8_REGEXP_LOONG64_REGEXP_MACRO_ASSEMBLER_LOONG64_H_
233