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_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_ 6 #define V8_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_ 7 8 #include "src/arm64/assembler-arm64.h" 9 #include "src/macro-assembler.h" 10 #include "src/regexp/regexp-macro-assembler.h" 11 12 namespace v8 { 13 namespace internal { 14 15 16 #ifndef V8_INTERPRETED_REGEXP 17 class RegExpMacroAssemblerARM64: public NativeRegExpMacroAssembler { 18 public: 19 RegExpMacroAssemblerARM64(Isolate* isolate, Zone* zone, Mode mode, 20 int registers_to_save); 21 virtual ~RegExpMacroAssemblerARM64(); AbortedCodeGeneration()22 virtual void AbortedCodeGeneration() { masm_->AbortedCodeGeneration(); } 23 virtual int stack_limit_slack(); 24 virtual void AdvanceCurrentPosition(int by); 25 virtual void AdvanceRegister(int reg, int by); 26 virtual void Backtrack(); 27 virtual void Bind(Label* label); 28 virtual void CheckAtStart(Label* on_at_start); 29 virtual void CheckCharacter(unsigned c, Label* on_equal); 30 virtual void CheckCharacterAfterAnd(unsigned c, 31 unsigned mask, 32 Label* on_equal); 33 virtual void CheckCharacterGT(uc16 limit, Label* on_greater); 34 virtual void CheckCharacterLT(uc16 limit, Label* on_less); 35 virtual void CheckCharacters(Vector<const uc16> str, 36 int cp_offset, 37 Label* on_failure, 38 bool check_end_of_string); 39 // A "greedy loop" is a loop that is both greedy and with a simple 40 // body. It has a particularly simple implementation. 41 virtual void CheckGreedyLoop(Label* on_tos_equals_current_position); 42 virtual void CheckNotAtStart(int cp_offset, Label* on_not_at_start); 43 virtual void CheckNotBackReference(int start_reg, bool read_backward, 44 Label* on_no_match); 45 virtual void CheckNotBackReferenceIgnoreCase(int start_reg, 46 bool read_backward, bool unicode, 47 Label* on_no_match); 48 virtual void CheckNotCharacter(unsigned c, Label* on_not_equal); 49 virtual void CheckNotCharacterAfterAnd(unsigned c, 50 unsigned mask, 51 Label* on_not_equal); 52 virtual void CheckNotCharacterAfterMinusAnd(uc16 c, 53 uc16 minus, 54 uc16 mask, 55 Label* on_not_equal); 56 virtual void CheckCharacterInRange(uc16 from, 57 uc16 to, 58 Label* on_in_range); 59 virtual void CheckCharacterNotInRange(uc16 from, 60 uc16 to, 61 Label* on_not_in_range); 62 virtual void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set); 63 64 // Checks whether the given offset from the current position is before 65 // the end of the string. 66 virtual void CheckPosition(int cp_offset, Label* on_outside_input); 67 virtual bool CheckSpecialCharacterClass(uc16 type, 68 Label* on_no_match); 69 virtual void Fail(); 70 virtual Handle<HeapObject> GetCode(Handle<String> source); 71 virtual void GoTo(Label* label); 72 virtual void IfRegisterGE(int reg, int comparand, Label* if_ge); 73 virtual void IfRegisterLT(int reg, int comparand, Label* if_lt); 74 virtual void IfRegisterEqPos(int reg, Label* if_eq); 75 virtual IrregexpImplementation Implementation(); 76 virtual void LoadCurrentCharacter(int cp_offset, 77 Label* on_end_of_input, 78 bool check_bounds = true, 79 int characters = 1); 80 virtual void PopCurrentPosition(); 81 virtual void PopRegister(int register_index); 82 virtual void PushBacktrack(Label* label); 83 virtual void PushCurrentPosition(); 84 virtual void PushRegister(int register_index, 85 StackCheckFlag check_stack_limit); 86 virtual void ReadCurrentPositionFromRegister(int reg); 87 virtual void ReadStackPointerFromRegister(int reg); 88 virtual void SetCurrentPositionFromEnd(int by); 89 virtual void SetRegister(int register_index, int to); 90 virtual bool Succeed(); 91 virtual void WriteCurrentPositionToRegister(int reg, int cp_offset); 92 virtual void ClearRegisters(int reg_from, int reg_to); 93 virtual void WriteStackPointerToRegister(int reg); 94 95 // Called from RegExp if the stack-guard is triggered. 96 // If the code object is relocated, the return address is fixed before 97 // returning. 98 static int CheckStackGuardState(Address* return_address, 99 Code* re_code, 100 Address re_frame, 101 int start_offset, 102 const byte** input_start, 103 const byte** input_end); 104 105 private: 106 // Above the frame pointer - Stored registers and stack passed parameters. 107 // Callee-saved registers x19-x29, where x29 is the old frame pointer. 108 static const int kCalleeSavedRegisters = 0; 109 // Return address. 110 // It is placed above the 11 callee-saved registers. 111 static const int kReturnAddress = kCalleeSavedRegisters + 11 * kPointerSize; 112 // Stack parameter placed by caller. 113 static const int kIsolate = kReturnAddress + kPointerSize; 114 115 // Below the frame pointer. 116 // Register parameters stored by setup code. 117 static const int kDirectCall = kCalleeSavedRegisters - kPointerSize; 118 static const int kStackBase = kDirectCall - kPointerSize; 119 static const int kOutputSize = kStackBase - kPointerSize; 120 static const int kInput = kOutputSize - kPointerSize; 121 // When adding local variables remember to push space for them in 122 // the frame in GetCode. 123 static const int kSuccessCounter = kInput - kPointerSize; 124 // First position register address on the stack. Following positions are 125 // below it. A position is a 32 bit value. 126 static const int kFirstRegisterOnStack = kSuccessCounter - kWRegSize; 127 // A capture is a 64 bit value holding two position. 128 static const int kFirstCaptureOnStack = kSuccessCounter - kXRegSize; 129 130 // Initial size of code buffer. 131 static const size_t kRegExpCodeSize = 1024; 132 133 // When initializing registers to a non-position value we can unroll 134 // the loop. Set the limit of registers to unroll. 135 static const int kNumRegistersToUnroll = 16; 136 137 // We are using x0 to x7 as a register cache. Each hardware register must 138 // contain one capture, that is two 32 bit registers. We can cache at most 139 // 16 registers. 140 static const int kNumCachedRegisters = 16; 141 142 // Load a number of characters at the given offset from the 143 // current position, into the current-character register. 144 void LoadCurrentCharacterUnchecked(int cp_offset, int character_count); 145 146 // Check whether preemption has been requested. 147 void CheckPreemption(); 148 149 // Check whether we are exceeding the stack limit on the backtrack stack. 150 void CheckStackLimit(); 151 152 // Generate a call to CheckStackGuardState. 153 void CallCheckStackGuardState(Register scratch); 154 155 // Location of a 32 bit position register. 156 MemOperand register_location(int register_index); 157 158 // Location of a 64 bit capture, combining two position registers. 159 MemOperand capture_location(int register_index, Register scratch); 160 161 // Register holding the current input position as negative offset from 162 // the end of the string. current_input_offset()163 Register current_input_offset() { return w21; } 164 165 // The register containing the current character after LoadCurrentCharacter. current_character()166 Register current_character() { return w22; } 167 168 // Register holding address of the end of the input string. input_end()169 Register input_end() { return x25; } 170 171 // Register holding address of the start of the input string. input_start()172 Register input_start() { return x26; } 173 174 // Register holding the offset from the start of the string where we should 175 // start matching. start_offset()176 Register start_offset() { return w27; } 177 178 // Pointer to the output array's first element. output_array()179 Register output_array() { return x28; } 180 181 // Register holding the frame address. Local variables, parameters and 182 // regexp registers are addressed relative to this. frame_pointer()183 Register frame_pointer() { return fp; } 184 185 // The register containing the backtrack stack top. Provides a meaningful 186 // name to the register. backtrack_stackpointer()187 Register backtrack_stackpointer() { return x23; } 188 189 // Register holding pointer to the current code object. code_pointer()190 Register code_pointer() { return x20; } 191 192 // Register holding the value used for clearing capture registers. string_start_minus_one()193 Register string_start_minus_one() { return w24; } 194 // The top 32 bit of this register is used to store this value 195 // twice. This is used for clearing more than one register at a time. twice_non_position_value()196 Register twice_non_position_value() { return x24; } 197 198 // Byte size of chars in the string to match (decided by the Mode argument) char_size()199 int char_size() { return static_cast<int>(mode_); } 200 201 // Equivalent to a conditional branch to the label, unless the label 202 // is nullptr, in which case it is a conditional Backtrack. 203 void BranchOrBacktrack(Condition condition, Label* to); 204 205 // Compares reg against immmediate before calling BranchOrBacktrack. 206 // It makes use of the Cbz and Cbnz instructions. 207 void CompareAndBranchOrBacktrack(Register reg, 208 int immediate, 209 Condition condition, 210 Label* to); 211 212 inline void CallIf(Label* to, Condition condition); 213 214 // Save and restore the link register on the stack in a way that 215 // is GC-safe. 216 inline void SaveLinkRegister(); 217 inline void RestoreLinkRegister(); 218 219 // Pushes the value of a register on the backtrack stack. Decrements the 220 // stack pointer by a word size and stores the register's value there. 221 inline void Push(Register source); 222 223 // Pops a value from the backtrack stack. Reads the word at the stack pointer 224 // and increments it by a word size. 225 inline void Pop(Register target); 226 227 // This state indicates where the register actually is. 228 enum RegisterState { 229 STACKED, // Resides in memory. 230 CACHED_LSW, // Least Significant Word of a 64 bit hardware register. 231 CACHED_MSW // Most Significant Word of a 64 bit hardware register. 232 }; 233 GetRegisterState(int register_index)234 RegisterState GetRegisterState(int register_index) { 235 DCHECK_LE(0, register_index); 236 if (register_index >= kNumCachedRegisters) { 237 return STACKED; 238 } else { 239 if ((register_index % 2) == 0) { 240 return CACHED_LSW; 241 } else { 242 return CACHED_MSW; 243 } 244 } 245 } 246 247 // Store helper that takes the state of the register into account. 248 inline void StoreRegister(int register_index, Register source); 249 250 // Returns a hardware W register that holds the value of the capture 251 // register. 252 // 253 // This function will try to use an existing cache register (w0-w7) for the 254 // result. Otherwise, it will load the value into maybe_result. 255 // 256 // If the returned register is anything other than maybe_result, calling code 257 // must not write to it. 258 inline Register GetRegister(int register_index, Register maybe_result); 259 260 // Returns the harware register (x0-x7) holding the value of the capture 261 // register. 262 // This assumes that the state of the register is not STACKED. 263 inline Register GetCachedRegister(int register_index); 264 isolate()265 Isolate* isolate() const { return masm_->isolate(); } 266 267 MacroAssembler* masm_; 268 269 // Which mode to generate code for (LATIN1 or UC16). 270 Mode mode_; 271 272 // One greater than maximal register index actually used. 273 int num_registers_; 274 275 // Number of registers to output at the end (the saved registers 276 // are always 0..num_saved_registers_-1) 277 int num_saved_registers_; 278 279 // Labels used internally. 280 Label entry_label_; 281 Label start_label_; 282 Label success_label_; 283 Label backtrack_label_; 284 Label exit_label_; 285 Label check_preempt_label_; 286 Label stack_overflow_label_; 287 }; 288 289 #endif // V8_INTERPRETED_REGEXP 290 291 292 } // namespace internal 293 } // namespace v8 294 295 #endif // V8_REGEXP_ARM64_REGEXP_MACRO_ASSEMBLER_ARM64_H_ 296