1 // Copyright 2013 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_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_ 6 #define V8_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_ 7 8 #include "src/macro-assembler.h" 9 10 #include "src/arm64/assembler-arm64.h" 11 #include "src/arm64/assembler-arm64-inl.h" 12 13 namespace v8 { 14 namespace internal { 15 16 17 #ifndef V8_INTERPRETED_REGEXP 18 class RegExpMacroAssemblerARM64: public NativeRegExpMacroAssembler { 19 public: 20 RegExpMacroAssemblerARM64(Mode mode, int registers_to_save, Zone* zone); 21 virtual ~RegExpMacroAssemblerARM64(); 22 virtual int stack_limit_slack(); 23 virtual void AdvanceCurrentPosition(int by); 24 virtual void AdvanceRegister(int reg, int by); 25 virtual void Backtrack(); 26 virtual void Bind(Label* label); 27 virtual void CheckAtStart(Label* on_at_start); 28 virtual void CheckCharacter(unsigned c, Label* on_equal); 29 virtual void CheckCharacterAfterAnd(unsigned c, 30 unsigned mask, 31 Label* on_equal); 32 virtual void CheckCharacterGT(uc16 limit, Label* on_greater); 33 virtual void CheckCharacterLT(uc16 limit, Label* on_less); 34 virtual void CheckCharacters(Vector<const uc16> str, 35 int cp_offset, 36 Label* on_failure, 37 bool check_end_of_string); 38 // A "greedy loop" is a loop that is both greedy and with a simple 39 // body. It has a particularly simple implementation. 40 virtual void CheckGreedyLoop(Label* on_tos_equals_current_position); 41 virtual void CheckNotAtStart(Label* on_not_at_start); 42 virtual void CheckNotBackReference(int start_reg, Label* on_no_match); 43 virtual void CheckNotBackReferenceIgnoreCase(int start_reg, 44 Label* on_no_match); 45 virtual void CheckNotCharacter(unsigned c, Label* on_not_equal); 46 virtual void CheckNotCharacterAfterAnd(unsigned c, 47 unsigned mask, 48 Label* on_not_equal); 49 virtual void CheckNotCharacterAfterMinusAnd(uc16 c, 50 uc16 minus, 51 uc16 mask, 52 Label* on_not_equal); 53 virtual void CheckCharacterInRange(uc16 from, 54 uc16 to, 55 Label* on_in_range); 56 virtual void CheckCharacterNotInRange(uc16 from, 57 uc16 to, 58 Label* on_not_in_range); 59 virtual void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set); 60 61 // Checks whether the given offset from the current position is before 62 // the end of the string. 63 virtual void CheckPosition(int cp_offset, Label* on_outside_input); 64 virtual bool CheckSpecialCharacterClass(uc16 type, 65 Label* on_no_match); 66 virtual void Fail(); 67 virtual Handle<HeapObject> GetCode(Handle<String> source); 68 virtual void GoTo(Label* label); 69 virtual void IfRegisterGE(int reg, int comparand, Label* if_ge); 70 virtual void IfRegisterLT(int reg, int comparand, Label* if_lt); 71 virtual void IfRegisterEqPos(int reg, Label* if_eq); 72 virtual IrregexpImplementation Implementation(); 73 virtual void LoadCurrentCharacter(int cp_offset, 74 Label* on_end_of_input, 75 bool check_bounds = true, 76 int characters = 1); 77 virtual void PopCurrentPosition(); 78 virtual void PopRegister(int register_index); 79 virtual void PushBacktrack(Label* label); 80 virtual void PushCurrentPosition(); 81 virtual void PushRegister(int register_index, 82 StackCheckFlag check_stack_limit); 83 virtual void ReadCurrentPositionFromRegister(int reg); 84 virtual void ReadStackPointerFromRegister(int reg); 85 virtual void SetCurrentPositionFromEnd(int by); 86 virtual void SetRegister(int register_index, int to); 87 virtual bool Succeed(); 88 virtual void WriteCurrentPositionToRegister(int reg, int cp_offset); 89 virtual void ClearRegisters(int reg_from, int reg_to); 90 virtual void WriteStackPointerToRegister(int reg); 91 virtual bool CanReadUnaligned(); 92 93 // Called from RegExp if the stack-guard is triggered. 94 // If the code object is relocated, the return address is fixed before 95 // returning. 96 static int CheckStackGuardState(Address* return_address, 97 Code* re_code, 98 Address re_frame, 99 int start_offset, 100 const byte** input_start, 101 const byte** input_end); 102 103 private: 104 // Above the frame pointer - Stored registers and stack passed parameters. 105 // Callee-saved registers x19-x29, where x29 is the old frame pointer. 106 static const int kCalleeSavedRegisters = 0; 107 // Return address. 108 // It is placed above the 11 callee-saved registers. 109 static const int kReturnAddress = kCalleeSavedRegisters + 11 * kPointerSize; 110 static const int kSecondaryReturnAddress = kReturnAddress + kPointerSize; 111 // Stack parameter placed by caller. 112 static const int kIsolate = kSecondaryReturnAddress + kPointerSize; 113 114 // Below the frame pointer. 115 // Register parameters stored by setup code. 116 static const int kDirectCall = kCalleeSavedRegisters - kPointerSize; 117 static const int kStackBase = kDirectCall - kPointerSize; 118 static const int kOutputSize = kStackBase - kPointerSize; 119 static const int kInput = kOutputSize - kPointerSize; 120 // When adding local variables remember to push space for them in 121 // the frame in GetCode. 122 static const int kSuccessCounter = kInput - kPointerSize; 123 // First position register address on the stack. Following positions are 124 // below it. A position is a 32 bit value. 125 static const int kFirstRegisterOnStack = kSuccessCounter - kWRegSize; 126 // A capture is a 64 bit value holding two position. 127 static const int kFirstCaptureOnStack = kSuccessCounter - kXRegSize; 128 129 // Initial size of code buffer. 130 static const size_t kRegExpCodeSize = 1024; 131 132 // When initializing registers to a non-position value we can unroll 133 // the loop. Set the limit of registers to unroll. 134 static const int kNumRegistersToUnroll = 16; 135 136 // We are using x0 to x7 as a register cache. Each hardware register must 137 // contain one capture, that is two 32 bit registers. We can cache at most 138 // 16 registers. 139 static const int kNumCachedRegisters = 16; 140 141 // Load a number of characters at the given offset from the 142 // current position, into the current-character register. 143 void LoadCurrentCharacterUnchecked(int cp_offset, int character_count); 144 145 // Check whether preemption has been requested. 146 void CheckPreemption(); 147 148 // Check whether we are exceeding the stack limit on the backtrack stack. 149 void CheckStackLimit(); 150 151 // Generate a call to CheckStackGuardState. 152 void CallCheckStackGuardState(Register scratch); 153 154 // Location of a 32 bit position register. 155 MemOperand register_location(int register_index); 156 157 // Location of a 64 bit capture, combining two position registers. 158 MemOperand capture_location(int register_index, Register scratch); 159 160 // Register holding the current input position as negative offset from 161 // the end of the string. 162 Register current_input_offset() { return w21; } 163 164 // The register containing the current character after LoadCurrentCharacter. 165 Register current_character() { return w22; } 166 167 // Register holding address of the end of the input string. 168 Register input_end() { return x25; } 169 170 // Register holding address of the start of the input string. 171 Register input_start() { return x26; } 172 173 // Register holding the offset from the start of the string where we should 174 // start matching. 175 Register start_offset() { return w27; } 176 177 // Pointer to the output array's first element. 178 Register output_array() { return x28; } 179 180 // Register holding the frame address. Local variables, parameters and 181 // regexp registers are addressed relative to this. 182 Register frame_pointer() { return fp; } 183 184 // The register containing the backtrack stack top. Provides a meaningful 185 // name to the register. 186 Register backtrack_stackpointer() { return x23; } 187 188 // Register holding pointer to the current code object. 189 Register code_pointer() { return x20; } 190 191 // Register holding the value used for clearing capture registers. 192 Register non_position_value() { return w24; } 193 // The top 32 bit of this register is used to store this value 194 // twice. This is used for clearing more than one register at a time. 195 Register twice_non_position_value() { return x24; } 196 197 // Byte size of chars in the string to match (decided by the Mode argument) 198 int char_size() { return static_cast<int>(mode_); } 199 200 // Equivalent to a conditional branch to the label, unless the label 201 // is NULL, in which case it is a conditional Backtrack. 202 void BranchOrBacktrack(Condition condition, Label* to); 203 204 // Compares reg against immmediate before calling BranchOrBacktrack. 205 // It makes use of the Cbz and Cbnz instructions. 206 void CompareAndBranchOrBacktrack(Register reg, 207 int immediate, 208 Condition condition, 209 Label* to); 210 211 inline void CallIf(Label* to, Condition condition); 212 213 // Save and restore the link register on the stack in a way that 214 // is GC-safe. 215 inline void SaveLinkRegister(); 216 inline void RestoreLinkRegister(); 217 218 // Pushes the value of a register on the backtrack stack. Decrements the 219 // stack pointer by a word size and stores the register's value there. 220 inline void Push(Register source); 221 222 // Pops a value from the backtrack stack. Reads the word at the stack pointer 223 // and increments it by a word size. 224 inline void Pop(Register target); 225 226 // This state indicates where the register actually is. 227 enum RegisterState { 228 STACKED, // Resides in memory. 229 CACHED_LSW, // Least Significant Word of a 64 bit hardware register. 230 CACHED_MSW // Most Significant Word of a 64 bit hardware register. 231 }; 232 233 RegisterState GetRegisterState(int register_index) { 234 DCHECK(register_index >= 0); 235 if (register_index >= kNumCachedRegisters) { 236 return STACKED; 237 } else { 238 if ((register_index % 2) == 0) { 239 return CACHED_LSW; 240 } else { 241 return CACHED_MSW; 242 } 243 } 244 } 245 246 // Store helper that takes the state of the register into account. 247 inline void StoreRegister(int register_index, Register source); 248 249 // Returns a hardware W register that holds the value of the capture 250 // register. 251 // 252 // This function will try to use an existing cache register (w0-w7) for the 253 // result. Otherwise, it will load the value into maybe_result. 254 // 255 // If the returned register is anything other than maybe_result, calling code 256 // must not write to it. 257 inline Register GetRegister(int register_index, Register maybe_result); 258 259 // Returns the harware register (x0-x7) holding the value of the capture 260 // register. 261 // This assumes that the state of the register is not STACKED. 262 inline Register GetCachedRegister(int register_index); 263 264 Isolate* isolate() const { return masm_->isolate(); } 265 266 MacroAssembler* masm_; 267 268 // Which mode to generate code for (LATIN1 or UC16). 269 Mode mode_; 270 271 // One greater than maximal register index actually used. 272 int num_registers_; 273 274 // Number of registers to output at the end (the saved registers 275 // are always 0..num_saved_registers_-1) 276 int num_saved_registers_; 277 278 // Labels used internally. 279 Label entry_label_; 280 Label start_label_; 281 Label success_label_; 282 Label backtrack_label_; 283 Label exit_label_; 284 Label check_preempt_label_; 285 Label stack_overflow_label_; 286 }; 287 288 #endif // V8_INTERPRETED_REGEXP 289 290 291 }} // namespace v8::internal 292 293 #endif // V8_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_ 294
