Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1 | // Copyright (c) 1994-2006 Sun Microsystems Inc. |
| 2 | // All Rights Reserved. |
| 3 | // |
| 4 | // Redistribution and use in source and binary forms, with or without |
| 5 | // modification, are permitted provided that the following conditions |
| 6 | // are met: |
| 7 | // |
| 8 | // - Redistributions of source code must retain the above copyright notice, |
| 9 | // this list of conditions and the following disclaimer. |
| 10 | // |
| 11 | // - Redistribution in binary form must reproduce the above copyright |
| 12 | // notice, this list of conditions and the following disclaimer in the |
| 13 | // documentation and/or other materials provided with the |
| 14 | // distribution. |
| 15 | // |
| 16 | // - Neither the name of Sun Microsystems or the names of contributors may |
| 17 | // be used to endorse or promote products derived from this software without |
| 18 | // specific prior written permission. |
| 19 | // |
| 20 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 21 | // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 22 | // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 23 | // FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 24 | // COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 25 | // INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| 26 | // (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| 27 | // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 28 | // HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| 29 | // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 30 | // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| 31 | // OF THE POSSIBILITY OF SUCH DAMAGE. |
| 32 | |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 33 | // The original source code covered by the above license above has been |
| 34 | // modified significantly by Google Inc. |
| 35 | // Copyright 2010 the V8 project authors. All rights reserved. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 36 | |
| 37 | // A light-weight ARM Assembler |
| 38 | // Generates user mode instructions for the ARM architecture up to version 5 |
| 39 | |
| 40 | #ifndef V8_ARM_ASSEMBLER_ARM_H_ |
| 41 | #define V8_ARM_ASSEMBLER_ARM_H_ |
| 42 | #include <stdio.h> |
| 43 | #include "assembler.h" |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 44 | #include "serialize.h" |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 45 | |
| 46 | namespace v8 { |
| 47 | namespace internal { |
| 48 | |
| 49 | // CPU Registers. |
| 50 | // |
| 51 | // 1) We would prefer to use an enum, but enum values are assignment- |
| 52 | // compatible with int, which has caused code-generation bugs. |
| 53 | // |
| 54 | // 2) We would prefer to use a class instead of a struct but we don't like |
| 55 | // the register initialization to depend on the particular initialization |
| 56 | // order (which appears to be different on OS X, Linux, and Windows for the |
| 57 | // installed versions of C++ we tried). Using a struct permits C-style |
| 58 | // "initialization". Also, the Register objects cannot be const as this |
| 59 | // forces initialization stubs in MSVC, making us dependent on initialization |
| 60 | // order. |
| 61 | // |
| 62 | // 3) By not using an enum, we are possibly preventing the compiler from |
| 63 | // doing certain constant folds, which may significantly reduce the |
| 64 | // code generated for some assembly instructions (because they boil down |
| 65 | // to a few constants). If this is a problem, we could change the code |
| 66 | // such that we use an enum in optimized mode, and the struct in debug |
| 67 | // mode. This way we get the compile-time error checking in debug mode |
| 68 | // and best performance in optimized code. |
| 69 | // |
| 70 | // Core register |
| 71 | struct Register { |
| 72 | bool is_valid() const { return 0 <= code_ && code_ < 16; } |
| 73 | bool is(Register reg) const { return code_ == reg.code_; } |
| 74 | int code() const { |
| 75 | ASSERT(is_valid()); |
| 76 | return code_; |
| 77 | } |
| 78 | int bit() const { |
| 79 | ASSERT(is_valid()); |
| 80 | return 1 << code_; |
| 81 | } |
| 82 | |
Andrei Popescu | 3100271 | 2010-02-23 13:46:05 +0000 | [diff] [blame] | 83 | // Unfortunately we can't make this private in a struct. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 84 | int code_; |
| 85 | }; |
| 86 | |
| 87 | |
| 88 | extern Register no_reg; |
| 89 | extern Register r0; |
| 90 | extern Register r1; |
| 91 | extern Register r2; |
| 92 | extern Register r3; |
| 93 | extern Register r4; |
| 94 | extern Register r5; |
| 95 | extern Register r6; |
| 96 | extern Register r7; |
| 97 | extern Register r8; |
| 98 | extern Register r9; |
| 99 | extern Register r10; |
| 100 | extern Register fp; |
| 101 | extern Register ip; |
| 102 | extern Register sp; |
| 103 | extern Register lr; |
| 104 | extern Register pc; |
| 105 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 106 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 107 | // Single word VFP register. |
| 108 | struct SwVfpRegister { |
| 109 | bool is_valid() const { return 0 <= code_ && code_ < 32; } |
| 110 | bool is(SwVfpRegister reg) const { return code_ == reg.code_; } |
| 111 | int code() const { |
| 112 | ASSERT(is_valid()); |
| 113 | return code_; |
| 114 | } |
| 115 | int bit() const { |
| 116 | ASSERT(is_valid()); |
| 117 | return 1 << code_; |
| 118 | } |
| 119 | |
| 120 | int code_; |
| 121 | }; |
| 122 | |
| 123 | |
| 124 | // Double word VFP register. |
| 125 | struct DwVfpRegister { |
| 126 | // Supporting d0 to d15, can be later extended to d31. |
| 127 | bool is_valid() const { return 0 <= code_ && code_ < 16; } |
| 128 | bool is(DwVfpRegister reg) const { return code_ == reg.code_; } |
| 129 | int code() const { |
| 130 | ASSERT(is_valid()); |
| 131 | return code_; |
| 132 | } |
| 133 | int bit() const { |
| 134 | ASSERT(is_valid()); |
| 135 | return 1 << code_; |
| 136 | } |
| 137 | |
| 138 | int code_; |
| 139 | }; |
| 140 | |
| 141 | |
| 142 | // Support for VFP registers s0 to s31 (d0 to d15). |
| 143 | // Note that "s(N):s(N+1)" is the same as "d(N/2)". |
| 144 | extern SwVfpRegister s0; |
| 145 | extern SwVfpRegister s1; |
| 146 | extern SwVfpRegister s2; |
| 147 | extern SwVfpRegister s3; |
| 148 | extern SwVfpRegister s4; |
| 149 | extern SwVfpRegister s5; |
| 150 | extern SwVfpRegister s6; |
| 151 | extern SwVfpRegister s7; |
| 152 | extern SwVfpRegister s8; |
| 153 | extern SwVfpRegister s9; |
| 154 | extern SwVfpRegister s10; |
| 155 | extern SwVfpRegister s11; |
| 156 | extern SwVfpRegister s12; |
| 157 | extern SwVfpRegister s13; |
| 158 | extern SwVfpRegister s14; |
| 159 | extern SwVfpRegister s15; |
| 160 | extern SwVfpRegister s16; |
| 161 | extern SwVfpRegister s17; |
| 162 | extern SwVfpRegister s18; |
| 163 | extern SwVfpRegister s19; |
| 164 | extern SwVfpRegister s20; |
| 165 | extern SwVfpRegister s21; |
| 166 | extern SwVfpRegister s22; |
| 167 | extern SwVfpRegister s23; |
| 168 | extern SwVfpRegister s24; |
| 169 | extern SwVfpRegister s25; |
| 170 | extern SwVfpRegister s26; |
| 171 | extern SwVfpRegister s27; |
| 172 | extern SwVfpRegister s28; |
| 173 | extern SwVfpRegister s29; |
| 174 | extern SwVfpRegister s30; |
| 175 | extern SwVfpRegister s31; |
| 176 | |
| 177 | extern DwVfpRegister d0; |
| 178 | extern DwVfpRegister d1; |
| 179 | extern DwVfpRegister d2; |
| 180 | extern DwVfpRegister d3; |
| 181 | extern DwVfpRegister d4; |
| 182 | extern DwVfpRegister d5; |
| 183 | extern DwVfpRegister d6; |
| 184 | extern DwVfpRegister d7; |
| 185 | extern DwVfpRegister d8; |
| 186 | extern DwVfpRegister d9; |
| 187 | extern DwVfpRegister d10; |
| 188 | extern DwVfpRegister d11; |
| 189 | extern DwVfpRegister d12; |
| 190 | extern DwVfpRegister d13; |
| 191 | extern DwVfpRegister d14; |
| 192 | extern DwVfpRegister d15; |
| 193 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 194 | |
| 195 | // Coprocessor register |
| 196 | struct CRegister { |
| 197 | bool is_valid() const { return 0 <= code_ && code_ < 16; } |
| 198 | bool is(CRegister creg) const { return code_ == creg.code_; } |
| 199 | int code() const { |
| 200 | ASSERT(is_valid()); |
| 201 | return code_; |
| 202 | } |
| 203 | int bit() const { |
| 204 | ASSERT(is_valid()); |
| 205 | return 1 << code_; |
| 206 | } |
| 207 | |
Andrei Popescu | 3100271 | 2010-02-23 13:46:05 +0000 | [diff] [blame] | 208 | // Unfortunately we can't make this private in a struct. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 209 | int code_; |
| 210 | }; |
| 211 | |
| 212 | |
| 213 | extern CRegister no_creg; |
| 214 | extern CRegister cr0; |
| 215 | extern CRegister cr1; |
| 216 | extern CRegister cr2; |
| 217 | extern CRegister cr3; |
| 218 | extern CRegister cr4; |
| 219 | extern CRegister cr5; |
| 220 | extern CRegister cr6; |
| 221 | extern CRegister cr7; |
| 222 | extern CRegister cr8; |
| 223 | extern CRegister cr9; |
| 224 | extern CRegister cr10; |
| 225 | extern CRegister cr11; |
| 226 | extern CRegister cr12; |
| 227 | extern CRegister cr13; |
| 228 | extern CRegister cr14; |
| 229 | extern CRegister cr15; |
| 230 | |
| 231 | |
| 232 | // Coprocessor number |
| 233 | enum Coprocessor { |
| 234 | p0 = 0, |
| 235 | p1 = 1, |
| 236 | p2 = 2, |
| 237 | p3 = 3, |
| 238 | p4 = 4, |
| 239 | p5 = 5, |
| 240 | p6 = 6, |
| 241 | p7 = 7, |
| 242 | p8 = 8, |
| 243 | p9 = 9, |
| 244 | p10 = 10, |
| 245 | p11 = 11, |
| 246 | p12 = 12, |
| 247 | p13 = 13, |
| 248 | p14 = 14, |
| 249 | p15 = 15 |
| 250 | }; |
| 251 | |
| 252 | |
Andrei Popescu | 3100271 | 2010-02-23 13:46:05 +0000 | [diff] [blame] | 253 | // Condition field in instructions. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 254 | enum Condition { |
| 255 | eq = 0 << 28, // Z set equal. |
| 256 | ne = 1 << 28, // Z clear not equal. |
| 257 | nz = 1 << 28, // Z clear not zero. |
| 258 | cs = 2 << 28, // C set carry set. |
| 259 | hs = 2 << 28, // C set unsigned higher or same. |
| 260 | cc = 3 << 28, // C clear carry clear. |
| 261 | lo = 3 << 28, // C clear unsigned lower. |
| 262 | mi = 4 << 28, // N set negative. |
| 263 | pl = 5 << 28, // N clear positive or zero. |
| 264 | vs = 6 << 28, // V set overflow. |
| 265 | vc = 7 << 28, // V clear no overflow. |
| 266 | hi = 8 << 28, // C set, Z clear unsigned higher. |
| 267 | ls = 9 << 28, // C clear or Z set unsigned lower or same. |
| 268 | ge = 10 << 28, // N == V greater or equal. |
| 269 | lt = 11 << 28, // N != V less than. |
| 270 | gt = 12 << 28, // Z clear, N == V greater than. |
| 271 | le = 13 << 28, // Z set or N != V less then or equal |
| 272 | al = 14 << 28 // always. |
| 273 | }; |
| 274 | |
| 275 | |
| 276 | // Returns the equivalent of !cc. |
| 277 | INLINE(Condition NegateCondition(Condition cc)); |
| 278 | |
| 279 | |
| 280 | // Corresponds to transposing the operands of a comparison. |
| 281 | inline Condition ReverseCondition(Condition cc) { |
| 282 | switch (cc) { |
| 283 | case lo: |
| 284 | return hi; |
| 285 | case hi: |
| 286 | return lo; |
| 287 | case hs: |
| 288 | return ls; |
| 289 | case ls: |
| 290 | return hs; |
| 291 | case lt: |
| 292 | return gt; |
| 293 | case gt: |
| 294 | return lt; |
| 295 | case ge: |
| 296 | return le; |
| 297 | case le: |
| 298 | return ge; |
| 299 | default: |
| 300 | return cc; |
| 301 | }; |
| 302 | } |
| 303 | |
| 304 | |
| 305 | // Branch hints are not used on the ARM. They are defined so that they can |
| 306 | // appear in shared function signatures, but will be ignored in ARM |
| 307 | // implementations. |
| 308 | enum Hint { no_hint }; |
| 309 | |
| 310 | // Hints are not used on the arm. Negating is trivial. |
| 311 | inline Hint NegateHint(Hint ignored) { return no_hint; } |
| 312 | |
| 313 | |
| 314 | // ----------------------------------------------------------------------------- |
| 315 | // Addressing modes and instruction variants |
| 316 | |
| 317 | // Shifter operand shift operation |
| 318 | enum ShiftOp { |
| 319 | LSL = 0 << 5, |
| 320 | LSR = 1 << 5, |
| 321 | ASR = 2 << 5, |
| 322 | ROR = 3 << 5, |
| 323 | RRX = -1 |
| 324 | }; |
| 325 | |
| 326 | |
| 327 | // Condition code updating mode |
| 328 | enum SBit { |
| 329 | SetCC = 1 << 20, // set condition code |
| 330 | LeaveCC = 0 << 20 // leave condition code unchanged |
| 331 | }; |
| 332 | |
| 333 | |
| 334 | // Status register selection |
| 335 | enum SRegister { |
| 336 | CPSR = 0 << 22, |
| 337 | SPSR = 1 << 22 |
| 338 | }; |
| 339 | |
| 340 | |
| 341 | // Status register fields |
| 342 | enum SRegisterField { |
| 343 | CPSR_c = CPSR | 1 << 16, |
| 344 | CPSR_x = CPSR | 1 << 17, |
| 345 | CPSR_s = CPSR | 1 << 18, |
| 346 | CPSR_f = CPSR | 1 << 19, |
| 347 | SPSR_c = SPSR | 1 << 16, |
| 348 | SPSR_x = SPSR | 1 << 17, |
| 349 | SPSR_s = SPSR | 1 << 18, |
| 350 | SPSR_f = SPSR | 1 << 19 |
| 351 | }; |
| 352 | |
| 353 | // Status register field mask (or'ed SRegisterField enum values) |
| 354 | typedef uint32_t SRegisterFieldMask; |
| 355 | |
| 356 | |
| 357 | // Memory operand addressing mode |
| 358 | enum AddrMode { |
| 359 | // bit encoding P U W |
| 360 | Offset = (8|4|0) << 21, // offset (without writeback to base) |
| 361 | PreIndex = (8|4|1) << 21, // pre-indexed addressing with writeback |
| 362 | PostIndex = (0|4|0) << 21, // post-indexed addressing with writeback |
| 363 | NegOffset = (8|0|0) << 21, // negative offset (without writeback to base) |
| 364 | NegPreIndex = (8|0|1) << 21, // negative pre-indexed with writeback |
| 365 | NegPostIndex = (0|0|0) << 21 // negative post-indexed with writeback |
| 366 | }; |
| 367 | |
| 368 | |
| 369 | // Load/store multiple addressing mode |
| 370 | enum BlockAddrMode { |
| 371 | // bit encoding P U W |
| 372 | da = (0|0|0) << 21, // decrement after |
| 373 | ia = (0|4|0) << 21, // increment after |
| 374 | db = (8|0|0) << 21, // decrement before |
| 375 | ib = (8|4|0) << 21, // increment before |
| 376 | da_w = (0|0|1) << 21, // decrement after with writeback to base |
| 377 | ia_w = (0|4|1) << 21, // increment after with writeback to base |
| 378 | db_w = (8|0|1) << 21, // decrement before with writeback to base |
| 379 | ib_w = (8|4|1) << 21 // increment before with writeback to base |
| 380 | }; |
| 381 | |
| 382 | |
| 383 | // Coprocessor load/store operand size |
| 384 | enum LFlag { |
| 385 | Long = 1 << 22, // long load/store coprocessor |
| 386 | Short = 0 << 22 // short load/store coprocessor |
| 387 | }; |
| 388 | |
| 389 | |
| 390 | // ----------------------------------------------------------------------------- |
| 391 | // Machine instruction Operands |
| 392 | |
| 393 | // Class Operand represents a shifter operand in data processing instructions |
| 394 | class Operand BASE_EMBEDDED { |
| 395 | public: |
| 396 | // immediate |
| 397 | INLINE(explicit Operand(int32_t immediate, |
| 398 | RelocInfo::Mode rmode = RelocInfo::NONE)); |
| 399 | INLINE(explicit Operand(const ExternalReference& f)); |
| 400 | INLINE(explicit Operand(const char* s)); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 401 | explicit Operand(Handle<Object> handle); |
| 402 | INLINE(explicit Operand(Smi* value)); |
| 403 | |
| 404 | // rm |
| 405 | INLINE(explicit Operand(Register rm)); |
| 406 | |
| 407 | // rm <shift_op> shift_imm |
| 408 | explicit Operand(Register rm, ShiftOp shift_op, int shift_imm); |
| 409 | |
| 410 | // rm <shift_op> rs |
| 411 | explicit Operand(Register rm, ShiftOp shift_op, Register rs); |
| 412 | |
| 413 | // Return true if this is a register operand. |
| 414 | INLINE(bool is_reg() const); |
| 415 | |
| 416 | Register rm() const { return rm_; } |
| 417 | |
| 418 | private: |
| 419 | Register rm_; |
| 420 | Register rs_; |
| 421 | ShiftOp shift_op_; |
| 422 | int shift_imm_; // valid if rm_ != no_reg && rs_ == no_reg |
| 423 | int32_t imm32_; // valid if rm_ == no_reg |
| 424 | RelocInfo::Mode rmode_; |
| 425 | |
| 426 | friend class Assembler; |
| 427 | }; |
| 428 | |
| 429 | |
| 430 | // Class MemOperand represents a memory operand in load and store instructions |
| 431 | class MemOperand BASE_EMBEDDED { |
| 432 | public: |
| 433 | // [rn +/- offset] Offset/NegOffset |
| 434 | // [rn +/- offset]! PreIndex/NegPreIndex |
| 435 | // [rn], +/- offset PostIndex/NegPostIndex |
| 436 | // offset is any signed 32-bit value; offset is first loaded to register ip if |
| 437 | // it does not fit the addressing mode (12-bit unsigned and sign bit) |
| 438 | explicit MemOperand(Register rn, int32_t offset = 0, AddrMode am = Offset); |
| 439 | |
| 440 | // [rn +/- rm] Offset/NegOffset |
| 441 | // [rn +/- rm]! PreIndex/NegPreIndex |
| 442 | // [rn], +/- rm PostIndex/NegPostIndex |
| 443 | explicit MemOperand(Register rn, Register rm, AddrMode am = Offset); |
| 444 | |
| 445 | // [rn +/- rm <shift_op> shift_imm] Offset/NegOffset |
| 446 | // [rn +/- rm <shift_op> shift_imm]! PreIndex/NegPreIndex |
| 447 | // [rn], +/- rm <shift_op> shift_imm PostIndex/NegPostIndex |
| 448 | explicit MemOperand(Register rn, Register rm, |
| 449 | ShiftOp shift_op, int shift_imm, AddrMode am = Offset); |
| 450 | |
| 451 | private: |
| 452 | Register rn_; // base |
| 453 | Register rm_; // register offset |
| 454 | int32_t offset_; // valid if rm_ == no_reg |
| 455 | ShiftOp shift_op_; |
| 456 | int shift_imm_; // valid if rm_ != no_reg && rs_ == no_reg |
| 457 | AddrMode am_; // bits P, U, and W |
| 458 | |
| 459 | friend class Assembler; |
| 460 | }; |
| 461 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 462 | // CpuFeatures keeps track of which features are supported by the target CPU. |
| 463 | // Supported features must be enabled by a Scope before use. |
| 464 | class CpuFeatures : public AllStatic { |
| 465 | public: |
| 466 | // Detect features of the target CPU. Set safe defaults if the serializer |
| 467 | // is enabled (snapshots must be portable). |
| 468 | static void Probe(); |
| 469 | |
| 470 | // Check whether a feature is supported by the target CPU. |
| 471 | static bool IsSupported(CpuFeature f) { |
| 472 | if (f == VFP3 && !FLAG_enable_vfp3) return false; |
| 473 | return (supported_ & (1u << f)) != 0; |
| 474 | } |
| 475 | |
| 476 | // Check whether a feature is currently enabled. |
| 477 | static bool IsEnabled(CpuFeature f) { |
| 478 | return (enabled_ & (1u << f)) != 0; |
| 479 | } |
| 480 | |
| 481 | // Enable a specified feature within a scope. |
| 482 | class Scope BASE_EMBEDDED { |
| 483 | #ifdef DEBUG |
| 484 | public: |
| 485 | explicit Scope(CpuFeature f) { |
| 486 | ASSERT(CpuFeatures::IsSupported(f)); |
| 487 | ASSERT(!Serializer::enabled() || |
| 488 | (found_by_runtime_probing_ & (1u << f)) == 0); |
| 489 | old_enabled_ = CpuFeatures::enabled_; |
| 490 | CpuFeatures::enabled_ |= 1u << f; |
| 491 | } |
| 492 | ~Scope() { CpuFeatures::enabled_ = old_enabled_; } |
| 493 | private: |
| 494 | unsigned old_enabled_; |
| 495 | #else |
| 496 | public: |
| 497 | explicit Scope(CpuFeature f) {} |
| 498 | #endif |
| 499 | }; |
| 500 | |
| 501 | private: |
| 502 | static unsigned supported_; |
| 503 | static unsigned enabled_; |
| 504 | static unsigned found_by_runtime_probing_; |
| 505 | }; |
| 506 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 507 | |
| 508 | typedef int32_t Instr; |
| 509 | |
| 510 | |
| 511 | extern const Instr kMovLrPc; |
| 512 | extern const Instr kLdrPCPattern; |
| 513 | |
| 514 | |
| 515 | class Assembler : public Malloced { |
| 516 | public: |
| 517 | // Create an assembler. Instructions and relocation information are emitted |
| 518 | // into a buffer, with the instructions starting from the beginning and the |
| 519 | // relocation information starting from the end of the buffer. See CodeDesc |
| 520 | // for a detailed comment on the layout (globals.h). |
| 521 | // |
| 522 | // If the provided buffer is NULL, the assembler allocates and grows its own |
| 523 | // buffer, and buffer_size determines the initial buffer size. The buffer is |
| 524 | // owned by the assembler and deallocated upon destruction of the assembler. |
| 525 | // |
| 526 | // If the provided buffer is not NULL, the assembler uses the provided buffer |
| 527 | // for code generation and assumes its size to be buffer_size. If the buffer |
| 528 | // is too small, a fatal error occurs. No deallocation of the buffer is done |
| 529 | // upon destruction of the assembler. |
| 530 | Assembler(void* buffer, int buffer_size); |
| 531 | ~Assembler(); |
| 532 | |
| 533 | // GetCode emits any pending (non-emitted) code and fills the descriptor |
| 534 | // desc. GetCode() is idempotent; it returns the same result if no other |
| 535 | // Assembler functions are invoked in between GetCode() calls. |
| 536 | void GetCode(CodeDesc* desc); |
| 537 | |
| 538 | // Label operations & relative jumps (PPUM Appendix D) |
| 539 | // |
| 540 | // Takes a branch opcode (cc) and a label (L) and generates |
| 541 | // either a backward branch or a forward branch and links it |
| 542 | // to the label fixup chain. Usage: |
| 543 | // |
| 544 | // Label L; // unbound label |
| 545 | // j(cc, &L); // forward branch to unbound label |
| 546 | // bind(&L); // bind label to the current pc |
| 547 | // j(cc, &L); // backward branch to bound label |
| 548 | // bind(&L); // illegal: a label may be bound only once |
| 549 | // |
| 550 | // Note: The same Label can be used for forward and backward branches |
| 551 | // but it may be bound only once. |
| 552 | |
| 553 | void bind(Label* L); // binds an unbound label L to the current code position |
| 554 | |
| 555 | // Returns the branch offset to the given label from the current code position |
| 556 | // Links the label to the current position if it is still unbound |
| 557 | // Manages the jump elimination optimization if the second parameter is true. |
| 558 | int branch_offset(Label* L, bool jump_elimination_allowed); |
| 559 | |
| 560 | // Puts a labels target address at the given position. |
| 561 | // The high 8 bits are set to zero. |
| 562 | void label_at_put(Label* L, int at_offset); |
| 563 | |
| 564 | // Return the address in the constant pool of the code target address used by |
| 565 | // the branch/call instruction at pc. |
| 566 | INLINE(static Address target_address_address_at(Address pc)); |
| 567 | |
| 568 | // Read/Modify the code target address in the branch/call instruction at pc. |
| 569 | INLINE(static Address target_address_at(Address pc)); |
| 570 | INLINE(static void set_target_address_at(Address pc, Address target)); |
| 571 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 572 | // This sets the branch destination (which is in the constant pool on ARM). |
| 573 | // This is for calls and branches within generated code. |
| 574 | inline static void set_target_at(Address constant_pool_entry, Address target); |
| 575 | |
| 576 | // This sets the branch destination (which is in the constant pool on ARM). |
| 577 | // This is for calls and branches to runtime code. |
| 578 | inline static void set_external_target_at(Address constant_pool_entry, |
| 579 | Address target) { |
| 580 | set_target_at(constant_pool_entry, target); |
| 581 | } |
| 582 | |
| 583 | // Here we are patching the address in the constant pool, not the actual call |
| 584 | // instruction. The address in the constant pool is the same size as a |
| 585 | // pointer. |
| 586 | static const int kCallTargetSize = kPointerSize; |
| 587 | static const int kExternalTargetSize = kPointerSize; |
| 588 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 589 | // Size of an instruction. |
| 590 | static const int kInstrSize = sizeof(Instr); |
| 591 | |
| 592 | // Distance between the instruction referring to the address of the call |
| 593 | // target (ldr pc, [target addr in const pool]) and the return address |
| 594 | static const int kCallTargetAddressOffset = kInstrSize; |
| 595 | |
| 596 | // Distance between start of patched return sequence and the emitted address |
| 597 | // to jump to. |
| 598 | static const int kPatchReturnSequenceAddressOffset = kInstrSize; |
| 599 | |
| 600 | // Difference between address of current opcode and value read from pc |
| 601 | // register. |
| 602 | static const int kPcLoadDelta = 8; |
| 603 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 604 | static const int kJSReturnSequenceLength = 4; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 605 | |
| 606 | // --------------------------------------------------------------------------- |
| 607 | // Code generation |
| 608 | |
| 609 | // Insert the smallest number of nop instructions |
| 610 | // possible to align the pc offset to a multiple |
| 611 | // of m. m must be a power of 2 (>= 4). |
| 612 | void Align(int m); |
| 613 | |
| 614 | // Branch instructions |
| 615 | void b(int branch_offset, Condition cond = al); |
| 616 | void bl(int branch_offset, Condition cond = al); |
| 617 | void blx(int branch_offset); // v5 and above |
| 618 | void blx(Register target, Condition cond = al); // v5 and above |
| 619 | void bx(Register target, Condition cond = al); // v5 and above, plus v4t |
| 620 | |
| 621 | // Convenience branch instructions using labels |
| 622 | void b(Label* L, Condition cond = al) { |
| 623 | b(branch_offset(L, cond == al), cond); |
| 624 | } |
| 625 | void b(Condition cond, Label* L) { b(branch_offset(L, cond == al), cond); } |
| 626 | void bl(Label* L, Condition cond = al) { bl(branch_offset(L, false), cond); } |
| 627 | void bl(Condition cond, Label* L) { bl(branch_offset(L, false), cond); } |
| 628 | void blx(Label* L) { blx(branch_offset(L, false)); } // v5 and above |
| 629 | |
| 630 | // Data-processing instructions |
Andrei Popescu | 3100271 | 2010-02-23 13:46:05 +0000 | [diff] [blame] | 631 | void ubfx(Register dst, Register src1, const Operand& src2, |
| 632 | const Operand& src3, Condition cond = al); |
| 633 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 634 | void and_(Register dst, Register src1, const Operand& src2, |
| 635 | SBit s = LeaveCC, Condition cond = al); |
| 636 | |
| 637 | void eor(Register dst, Register src1, const Operand& src2, |
| 638 | SBit s = LeaveCC, Condition cond = al); |
| 639 | |
| 640 | void sub(Register dst, Register src1, const Operand& src2, |
| 641 | SBit s = LeaveCC, Condition cond = al); |
| 642 | void sub(Register dst, Register src1, Register src2, |
| 643 | SBit s = LeaveCC, Condition cond = al) { |
| 644 | sub(dst, src1, Operand(src2), s, cond); |
| 645 | } |
| 646 | |
| 647 | void rsb(Register dst, Register src1, const Operand& src2, |
| 648 | SBit s = LeaveCC, Condition cond = al); |
| 649 | |
| 650 | void add(Register dst, Register src1, const Operand& src2, |
| 651 | SBit s = LeaveCC, Condition cond = al); |
| 652 | |
| 653 | void adc(Register dst, Register src1, const Operand& src2, |
| 654 | SBit s = LeaveCC, Condition cond = al); |
| 655 | |
| 656 | void sbc(Register dst, Register src1, const Operand& src2, |
| 657 | SBit s = LeaveCC, Condition cond = al); |
| 658 | |
| 659 | void rsc(Register dst, Register src1, const Operand& src2, |
| 660 | SBit s = LeaveCC, Condition cond = al); |
| 661 | |
| 662 | void tst(Register src1, const Operand& src2, Condition cond = al); |
| 663 | void tst(Register src1, Register src2, Condition cond = al) { |
| 664 | tst(src1, Operand(src2), cond); |
| 665 | } |
| 666 | |
| 667 | void teq(Register src1, const Operand& src2, Condition cond = al); |
| 668 | |
| 669 | void cmp(Register src1, const Operand& src2, Condition cond = al); |
| 670 | void cmp(Register src1, Register src2, Condition cond = al) { |
| 671 | cmp(src1, Operand(src2), cond); |
| 672 | } |
| 673 | |
| 674 | void cmn(Register src1, const Operand& src2, Condition cond = al); |
| 675 | |
| 676 | void orr(Register dst, Register src1, const Operand& src2, |
| 677 | SBit s = LeaveCC, Condition cond = al); |
| 678 | void orr(Register dst, Register src1, Register src2, |
| 679 | SBit s = LeaveCC, Condition cond = al) { |
| 680 | orr(dst, src1, Operand(src2), s, cond); |
| 681 | } |
| 682 | |
| 683 | void mov(Register dst, const Operand& src, |
| 684 | SBit s = LeaveCC, Condition cond = al); |
| 685 | void mov(Register dst, Register src, SBit s = LeaveCC, Condition cond = al) { |
| 686 | mov(dst, Operand(src), s, cond); |
| 687 | } |
| 688 | |
| 689 | void bic(Register dst, Register src1, const Operand& src2, |
| 690 | SBit s = LeaveCC, Condition cond = al); |
| 691 | |
| 692 | void mvn(Register dst, const Operand& src, |
| 693 | SBit s = LeaveCC, Condition cond = al); |
| 694 | |
| 695 | // Multiply instructions |
| 696 | |
| 697 | void mla(Register dst, Register src1, Register src2, Register srcA, |
| 698 | SBit s = LeaveCC, Condition cond = al); |
| 699 | |
| 700 | void mul(Register dst, Register src1, Register src2, |
| 701 | SBit s = LeaveCC, Condition cond = al); |
| 702 | |
| 703 | void smlal(Register dstL, Register dstH, Register src1, Register src2, |
| 704 | SBit s = LeaveCC, Condition cond = al); |
| 705 | |
| 706 | void smull(Register dstL, Register dstH, Register src1, Register src2, |
| 707 | SBit s = LeaveCC, Condition cond = al); |
| 708 | |
| 709 | void umlal(Register dstL, Register dstH, Register src1, Register src2, |
| 710 | SBit s = LeaveCC, Condition cond = al); |
| 711 | |
| 712 | void umull(Register dstL, Register dstH, Register src1, Register src2, |
| 713 | SBit s = LeaveCC, Condition cond = al); |
| 714 | |
| 715 | // Miscellaneous arithmetic instructions |
| 716 | |
| 717 | void clz(Register dst, Register src, Condition cond = al); // v5 and above |
| 718 | |
| 719 | // Status register access instructions |
| 720 | |
| 721 | void mrs(Register dst, SRegister s, Condition cond = al); |
| 722 | void msr(SRegisterFieldMask fields, const Operand& src, Condition cond = al); |
| 723 | |
| 724 | // Load/Store instructions |
| 725 | void ldr(Register dst, const MemOperand& src, Condition cond = al); |
| 726 | void str(Register src, const MemOperand& dst, Condition cond = al); |
| 727 | void ldrb(Register dst, const MemOperand& src, Condition cond = al); |
| 728 | void strb(Register src, const MemOperand& dst, Condition cond = al); |
| 729 | void ldrh(Register dst, const MemOperand& src, Condition cond = al); |
| 730 | void strh(Register src, const MemOperand& dst, Condition cond = al); |
| 731 | void ldrsb(Register dst, const MemOperand& src, Condition cond = al); |
| 732 | void ldrsh(Register dst, const MemOperand& src, Condition cond = al); |
| 733 | |
| 734 | // Load/Store multiple instructions |
| 735 | void ldm(BlockAddrMode am, Register base, RegList dst, Condition cond = al); |
| 736 | void stm(BlockAddrMode am, Register base, RegList src, Condition cond = al); |
| 737 | |
| 738 | // Semaphore instructions |
| 739 | void swp(Register dst, Register src, Register base, Condition cond = al); |
| 740 | void swpb(Register dst, Register src, Register base, Condition cond = al); |
| 741 | |
| 742 | // Exception-generating instructions and debugging support |
| 743 | void stop(const char* msg); |
| 744 | |
| 745 | void bkpt(uint32_t imm16); // v5 and above |
| 746 | void swi(uint32_t imm24, Condition cond = al); |
| 747 | |
| 748 | // Coprocessor instructions |
| 749 | |
| 750 | void cdp(Coprocessor coproc, int opcode_1, |
| 751 | CRegister crd, CRegister crn, CRegister crm, |
| 752 | int opcode_2, Condition cond = al); |
| 753 | |
| 754 | void cdp2(Coprocessor coproc, int opcode_1, |
| 755 | CRegister crd, CRegister crn, CRegister crm, |
| 756 | int opcode_2); // v5 and above |
| 757 | |
| 758 | void mcr(Coprocessor coproc, int opcode_1, |
| 759 | Register rd, CRegister crn, CRegister crm, |
| 760 | int opcode_2 = 0, Condition cond = al); |
| 761 | |
| 762 | void mcr2(Coprocessor coproc, int opcode_1, |
| 763 | Register rd, CRegister crn, CRegister crm, |
| 764 | int opcode_2 = 0); // v5 and above |
| 765 | |
| 766 | void mrc(Coprocessor coproc, int opcode_1, |
| 767 | Register rd, CRegister crn, CRegister crm, |
| 768 | int opcode_2 = 0, Condition cond = al); |
| 769 | |
| 770 | void mrc2(Coprocessor coproc, int opcode_1, |
| 771 | Register rd, CRegister crn, CRegister crm, |
| 772 | int opcode_2 = 0); // v5 and above |
| 773 | |
| 774 | void ldc(Coprocessor coproc, CRegister crd, const MemOperand& src, |
| 775 | LFlag l = Short, Condition cond = al); |
| 776 | void ldc(Coprocessor coproc, CRegister crd, Register base, int option, |
| 777 | LFlag l = Short, Condition cond = al); |
| 778 | |
| 779 | void ldc2(Coprocessor coproc, CRegister crd, const MemOperand& src, |
| 780 | LFlag l = Short); // v5 and above |
| 781 | void ldc2(Coprocessor coproc, CRegister crd, Register base, int option, |
| 782 | LFlag l = Short); // v5 and above |
| 783 | |
| 784 | void stc(Coprocessor coproc, CRegister crd, const MemOperand& dst, |
| 785 | LFlag l = Short, Condition cond = al); |
| 786 | void stc(Coprocessor coproc, CRegister crd, Register base, int option, |
| 787 | LFlag l = Short, Condition cond = al); |
| 788 | |
| 789 | void stc2(Coprocessor coproc, CRegister crd, const MemOperand& dst, |
| 790 | LFlag l = Short); // v5 and above |
| 791 | void stc2(Coprocessor coproc, CRegister crd, Register base, int option, |
| 792 | LFlag l = Short); // v5 and above |
| 793 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 794 | // Support for VFP. |
| 795 | // All these APIs support S0 to S31 and D0 to D15. |
| 796 | // Currently these APIs do not support extended D registers, i.e, D16 to D31. |
| 797 | // However, some simple modifications can allow |
| 798 | // these APIs to support D16 to D31. |
| 799 | |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 800 | void vldr(const DwVfpRegister dst, |
| 801 | const Register base, |
| 802 | int offset, // Offset must be a multiple of 4. |
| 803 | const Condition cond = al); |
| 804 | void vstr(const DwVfpRegister src, |
| 805 | const Register base, |
| 806 | int offset, // Offset must be a multiple of 4. |
| 807 | const Condition cond = al); |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 808 | void vmov(const DwVfpRegister dst, |
| 809 | const Register src1, |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 810 | const Register src2, |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 811 | const Condition cond = al); |
| 812 | void vmov(const Register dst1, |
| 813 | const Register dst2, |
| 814 | const DwVfpRegister src, |
| 815 | const Condition cond = al); |
| 816 | void vmov(const SwVfpRegister dst, |
| 817 | const Register src, |
| 818 | const Condition cond = al); |
| 819 | void vmov(const Register dst, |
| 820 | const SwVfpRegister src, |
| 821 | const Condition cond = al); |
| 822 | void vcvt(const DwVfpRegister dst, |
| 823 | const SwVfpRegister src, |
| 824 | const Condition cond = al); |
| 825 | void vcvt(const SwVfpRegister dst, |
| 826 | const DwVfpRegister src, |
| 827 | const Condition cond = al); |
| 828 | |
| 829 | void vadd(const DwVfpRegister dst, |
| 830 | const DwVfpRegister src1, |
| 831 | const DwVfpRegister src2, |
| 832 | const Condition cond = al); |
| 833 | void vsub(const DwVfpRegister dst, |
| 834 | const DwVfpRegister src1, |
| 835 | const DwVfpRegister src2, |
| 836 | const Condition cond = al); |
| 837 | void vmul(const DwVfpRegister dst, |
| 838 | const DwVfpRegister src1, |
| 839 | const DwVfpRegister src2, |
| 840 | const Condition cond = al); |
| 841 | void vdiv(const DwVfpRegister dst, |
| 842 | const DwVfpRegister src1, |
| 843 | const DwVfpRegister src2, |
| 844 | const Condition cond = al); |
| 845 | void vcmp(const DwVfpRegister src1, |
| 846 | const DwVfpRegister src2, |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 847 | const SBit s = LeaveCC, |
| 848 | const Condition cond = al); |
| 849 | void vmrs(const Register dst, |
| 850 | const Condition cond = al); |
| 851 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 852 | // Pseudo instructions |
| 853 | void nop() { mov(r0, Operand(r0)); } |
| 854 | |
| 855 | void push(Register src, Condition cond = al) { |
| 856 | str(src, MemOperand(sp, 4, NegPreIndex), cond); |
| 857 | } |
| 858 | |
| 859 | void pop(Register dst, Condition cond = al) { |
| 860 | ldr(dst, MemOperand(sp, 4, PostIndex), cond); |
| 861 | } |
| 862 | |
| 863 | void pop() { |
| 864 | add(sp, sp, Operand(kPointerSize)); |
| 865 | } |
| 866 | |
| 867 | // Load effective address of memory operand x into register dst |
| 868 | void lea(Register dst, const MemOperand& x, |
| 869 | SBit s = LeaveCC, Condition cond = al); |
| 870 | |
| 871 | // Jump unconditionally to given label. |
| 872 | void jmp(Label* L) { b(L, al); } |
| 873 | |
| 874 | // Check the code size generated from label to here. |
| 875 | int InstructionsGeneratedSince(Label* l) { |
| 876 | return (pc_offset() - l->pos()) / kInstrSize; |
| 877 | } |
| 878 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 879 | // Check whether an immediate fits an addressing mode 1 instruction. |
| 880 | bool ImmediateFitsAddrMode1Instruction(int32_t imm32); |
| 881 | |
| 882 | // Postpone the generation of the constant pool for the specified number of |
| 883 | // instructions. |
| 884 | void BlockConstPoolFor(int instructions); |
| 885 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 886 | // Debugging |
| 887 | |
| 888 | // Mark address of the ExitJSFrame code. |
| 889 | void RecordJSReturn(); |
| 890 | |
| 891 | // Record a comment relocation entry that can be used by a disassembler. |
| 892 | // Use --debug_code to enable. |
| 893 | void RecordComment(const char* msg); |
| 894 | |
| 895 | void RecordPosition(int pos); |
| 896 | void RecordStatementPosition(int pos); |
| 897 | void WriteRecordedPositions(); |
| 898 | |
| 899 | int pc_offset() const { return pc_ - buffer_; } |
| 900 | int current_position() const { return current_position_; } |
| 901 | int current_statement_position() const { return current_position_; } |
| 902 | |
| 903 | protected: |
| 904 | int buffer_space() const { return reloc_info_writer.pos() - pc_; } |
| 905 | |
| 906 | // Read/patch instructions |
| 907 | static Instr instr_at(byte* pc) { return *reinterpret_cast<Instr*>(pc); } |
| 908 | void instr_at_put(byte* pc, Instr instr) { |
| 909 | *reinterpret_cast<Instr*>(pc) = instr; |
| 910 | } |
| 911 | Instr instr_at(int pos) { return *reinterpret_cast<Instr*>(buffer_ + pos); } |
| 912 | void instr_at_put(int pos, Instr instr) { |
| 913 | *reinterpret_cast<Instr*>(buffer_ + pos) = instr; |
| 914 | } |
| 915 | |
| 916 | // Decode branch instruction at pos and return branch target pos |
| 917 | int target_at(int pos); |
| 918 | |
| 919 | // Patch branch instruction at pos to branch to given branch target pos |
| 920 | void target_at_put(int pos, int target_pos); |
| 921 | |
| 922 | // Check if is time to emit a constant pool for pending reloc info entries |
| 923 | void CheckConstPool(bool force_emit, bool require_jump); |
| 924 | |
| 925 | // Block the emission of the constant pool before pc_offset |
| 926 | void BlockConstPoolBefore(int pc_offset) { |
| 927 | if (no_const_pool_before_ < pc_offset) no_const_pool_before_ = pc_offset; |
| 928 | } |
| 929 | |
| 930 | private: |
| 931 | // Code buffer: |
| 932 | // The buffer into which code and relocation info are generated. |
| 933 | byte* buffer_; |
| 934 | int buffer_size_; |
| 935 | // True if the assembler owns the buffer, false if buffer is external. |
| 936 | bool own_buffer_; |
| 937 | |
| 938 | // Buffer size and constant pool distance are checked together at regular |
| 939 | // intervals of kBufferCheckInterval emitted bytes |
| 940 | static const int kBufferCheckInterval = 1*KB/2; |
| 941 | int next_buffer_check_; // pc offset of next buffer check |
| 942 | |
| 943 | // Code generation |
| 944 | // The relocation writer's position is at least kGap bytes below the end of |
| 945 | // the generated instructions. This is so that multi-instruction sequences do |
| 946 | // not have to check for overflow. The same is true for writes of large |
| 947 | // relocation info entries. |
| 948 | static const int kGap = 32; |
| 949 | byte* pc_; // the program counter; moves forward |
| 950 | |
| 951 | // Constant pool generation |
| 952 | // Pools are emitted in the instruction stream, preferably after unconditional |
| 953 | // jumps or after returns from functions (in dead code locations). |
| 954 | // If a long code sequence does not contain unconditional jumps, it is |
| 955 | // necessary to emit the constant pool before the pool gets too far from the |
| 956 | // location it is accessed from. In this case, we emit a jump over the emitted |
| 957 | // constant pool. |
| 958 | // Constants in the pool may be addresses of functions that gets relocated; |
| 959 | // if so, a relocation info entry is associated to the constant pool entry. |
| 960 | |
| 961 | // Repeated checking whether the constant pool should be emitted is rather |
| 962 | // expensive. By default we only check again once a number of instructions |
| 963 | // has been generated. That also means that the sizing of the buffers is not |
| 964 | // an exact science, and that we rely on some slop to not overrun buffers. |
| 965 | static const int kCheckConstIntervalInst = 32; |
| 966 | static const int kCheckConstInterval = kCheckConstIntervalInst * kInstrSize; |
| 967 | |
| 968 | |
| 969 | // Pools are emitted after function return and in dead code at (more or less) |
| 970 | // regular intervals of kDistBetweenPools bytes |
| 971 | static const int kDistBetweenPools = 1*KB; |
| 972 | |
| 973 | // Constants in pools are accessed via pc relative addressing, which can |
| 974 | // reach +/-4KB thereby defining a maximum distance between the instruction |
| 975 | // and the accessed constant. We satisfy this constraint by limiting the |
| 976 | // distance between pools. |
| 977 | static const int kMaxDistBetweenPools = 4*KB - 2*kBufferCheckInterval; |
| 978 | |
| 979 | // Emission of the constant pool may be blocked in some code sequences |
| 980 | int no_const_pool_before_; // block emission before this pc offset |
| 981 | |
| 982 | // Keep track of the last emitted pool to guarantee a maximal distance |
| 983 | int last_const_pool_end_; // pc offset following the last constant pool |
| 984 | |
| 985 | // Relocation info generation |
| 986 | // Each relocation is encoded as a variable size value |
| 987 | static const int kMaxRelocSize = RelocInfoWriter::kMaxSize; |
| 988 | RelocInfoWriter reloc_info_writer; |
| 989 | // Relocation info records are also used during code generation as temporary |
| 990 | // containers for constants and code target addresses until they are emitted |
| 991 | // to the constant pool. These pending relocation info records are temporarily |
| 992 | // stored in a separate buffer until a constant pool is emitted. |
| 993 | // If every instruction in a long sequence is accessing the pool, we need one |
| 994 | // pending relocation entry per instruction. |
| 995 | static const int kMaxNumPRInfo = kMaxDistBetweenPools/kInstrSize; |
| 996 | RelocInfo prinfo_[kMaxNumPRInfo]; // the buffer of pending relocation info |
| 997 | int num_prinfo_; // number of pending reloc info entries in the buffer |
| 998 | |
| 999 | // The bound position, before this we cannot do instruction elimination. |
| 1000 | int last_bound_pos_; |
| 1001 | |
| 1002 | // source position information |
| 1003 | int current_position_; |
| 1004 | int current_statement_position_; |
| 1005 | int written_position_; |
| 1006 | int written_statement_position_; |
| 1007 | |
| 1008 | // Code emission |
| 1009 | inline void CheckBuffer(); |
| 1010 | void GrowBuffer(); |
| 1011 | inline void emit(Instr x); |
| 1012 | |
| 1013 | // Instruction generation |
| 1014 | void addrmod1(Instr instr, Register rn, Register rd, const Operand& x); |
| 1015 | void addrmod2(Instr instr, Register rd, const MemOperand& x); |
| 1016 | void addrmod3(Instr instr, Register rd, const MemOperand& x); |
| 1017 | void addrmod4(Instr instr, Register rn, RegList rl); |
| 1018 | void addrmod5(Instr instr, CRegister crd, const MemOperand& x); |
| 1019 | |
| 1020 | // Labels |
| 1021 | void print(Label* L); |
| 1022 | void bind_to(Label* L, int pos); |
| 1023 | void link_to(Label* L, Label* appendix); |
| 1024 | void next(Label* L); |
| 1025 | |
| 1026 | // Record reloc info for current pc_ |
| 1027 | void RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data = 0); |
| 1028 | |
| 1029 | friend class RegExpMacroAssemblerARM; |
| 1030 | friend class RelocInfo; |
| 1031 | friend class CodePatcher; |
| 1032 | }; |
| 1033 | |
| 1034 | } } // namespace v8::internal |
| 1035 | |
| 1036 | #endif // V8_ARM_ASSEMBLER_ARM_H_ |