hphp/hhbbc/bc.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16 #ifndef incl_HHBBC_BC_H_
  17 #define incl_HHBBC_BC_H_
  18
  19 #include <vector>
  20 #include <utility>
  21 #include <type_traits>
  22
  23 #include <algorithm>
  24
  25 #include <folly/Hash.h>
  26
  27 #include "hphp/util/compact-vector.h"
  28 #include "hphp/runtime/vm/hhbc.h"
  29
  30 #include "hphp/hhbbc/src-loc.h"
  31 #include "hphp/hhbbc/misc.h"
  32 #include "hphp/hhbbc/type-system.h"
  33
  34 namespace HPHP { namespace HHBBC {
  35
  36 struct Bytecode;
  37
  38 //////////////////////////////////////////////////////////////////////
  39
  40 /*
  41  * The following creates a struct for each bytecode using the opcode
  42  * table.  Each opcode will be named bc::opcode, and has a single
  43  * constructor that takes its immediate types in order.
  44  *
  45  * E.g.
  46  *
  47  *   auto pushInt = bc::Int { 2 };  // Push literal int
  48  */
  49
  50 //////////////////////////////////////////////////////////////////////
  51
  52 struct MKey {
  53   MKey()
  54     : mcode{MW}
  55     , int64{0}
  56   {}
  57
  58   MKey(MemberCode mcode, LocalId local)
  59     : mcode{mcode}
  60     , local{local}
  61   {}
  62
  63   MKey(MemberCode mcode, int32_t idx)
  64     : mcode{mcode}
  65     , idx{idx}
  66   {}
  67
  68   MKey(MemberCode mcode, int64_t int64)
  69     : mcode{mcode}
  70     , int64{int64}
  71   {}
  72
  73   MKey(MemberCode mcode, SString litstr)
  74     : mcode{mcode}
  75     , litstr{litstr}
  76   {}
  77
  78   MemberCode mcode;
  79   union {
  80     SString litstr;
  81     int64_t int64;
  82     int64_t idx;
  83     LocalId local;
  84   };
  85 };
  86
  87 inline bool operator==(MKey a, MKey b) {
  88   return a.mcode == b.mcode && a.int64 == b.int64;
  89 }
  90
  91 inline bool operator!=(MKey a, MKey b) {
  92   return !(a == b);
  93 }
  94
  95 // A contiguous range of locals. The count is the number of locals including the
  96 // first. If the range is empty, count will be zero and first's value is
  97 // arbitrary.
  98 struct LocalRange {
  99   LocalId  first;
 100   uint32_t count;
 101 };
 102
 103 inline bool operator==(const LocalRange& a, const LocalRange& b) {
 104   return a.first == b.first && a.count == b.count;
 105 }
 106
 107 inline bool operator!=(const LocalRange& a, const LocalRange& b) {
 108   return !(a == b);
 109 }
 110
 111 struct FCallArgs : FCallArgsBase {
 112   explicit FCallArgs(uint32_t numArgs)
 113     : FCallArgs(Flags::None, numArgs, 1, nullptr, NoBlockId) {}
 114   explicit FCallArgs(Flags flags, uint32_t numArgs, uint32_t numRets,
 115                      std::unique_ptr<uint8_t[]> byRefs,
 116                      BlockId asyncEagerTarget)
 117     : FCallArgsBase(flags, numArgs, numRets)
 118     , asyncEagerTarget(asyncEagerTarget)
 119     , byRefs(std::move(byRefs)) {
 120     assertx(IMPLIES(asyncEagerTarget == NoBlockId,
 121                     !supportsAsyncEagerReturn()));
 122   }
 123   FCallArgs(const FCallArgs& o)
 124     : FCallArgs(o.flags, o.numArgs, o.numRets, nullptr, o.asyncEagerTarget) {
 125     if (o.byRefs) {
 126       auto const numBytes = (numArgs + 7) / 8;
 127       byRefs = std::make_unique<uint8_t[]>(numBytes);
 128       memcpy(byRefs.get(), o.byRefs.get(), numBytes);
 129     }
 130   }
 131   FCallArgs(FCallArgs&& o)
 132     : FCallArgs(o.flags, o.numArgs, o.numRets, std::move(o.byRefs),
 133                 o.asyncEagerTarget) {}
 134
 135   bool enforceReffiness() const { return byRefs.get() != nullptr; }
 136   bool byRef(uint32_t i) const {
 137     assertx(enforceReffiness());
 138     return byRefs[i / 8] & (1 << (i % 8));
 139   }
 140   BlockId asyncEagerTarget;
 141   std::unique_ptr<uint8_t[]> byRefs;
 142 };
 143
 144 inline bool operator==(const FCallArgs& a, const FCallArgs& b) {
 145   auto const eq = [&] (uint8_t* a, uint8_t* b, uint32_t bytes) {
 146     if (a == nullptr && b == nullptr) return true;
 147     if (a == nullptr || b == nullptr) return false;
 148     return memcmp(a, b, bytes) == 0;
 149   };
 150
 151   return
 152     a.flags == b.flags && a.numArgs == b.numArgs && a.numRets == b.numRets &&
 153     eq(a.byRefs.get(), b.byRefs.get(), (a.numArgs + 7 / 8)) &&
 154     a.asyncEagerTarget == b.asyncEagerTarget;
 155 }
 156
 157 inline bool operator!=(const FCallArgs& a, const FCallArgs& b) {
 158   return !(a == b);
 159 }
 160
 161 struct IterTabEnt {
 162   IterKind kind;
 163   IterId id;
 164   LocalId local;
 165 };
 166
 167 inline bool operator==(const IterTabEnt& a, const IterTabEnt& b) {
 168   return std::tie(a.kind, a.id, a.local) == std::tie(b.kind, b.id, b.local);
 169 }
 170
 171 inline bool operator!=(const IterTabEnt& a, const IterTabEnt& b) {
 172   return !(a == b);
 173 }
 174
 175 using IterTab       = CompactVector<IterTabEnt>;
 176
 177 using SwitchTab     = CompactVector<BlockId>;
 178
 179 // The final entry in the SSwitchTab is the default case, it will
 180 // always have a nullptr for the string.
 181 using SSwitchTabEnt = std::pair<LSString,BlockId>;
 182 using SSwitchTab    = CompactVector<SSwitchTabEnt>;
 183
 184 //////////////////////////////////////////////////////////////////////
 185
 186 namespace bc {
 187
 188 //////////////////////////////////////////////////////////////////////
 189
 190 namespace detail {
 191
 192 /*
 193  * Trivial hasher overrides, which will cause bytecodes to hash according to
 194  * the hashes defined by hasher_impl.
 195  */
 196 struct hasher_default {};
 197
 198 /*
 199  * Default bytecode immediate hashers.
 200  */
 201 struct hasher_impl {
 202   static size_t hash(SString s)  { return s->hash(); }
 203   static size_t hash(LSString s) { return s->hash(); }
 204   static size_t hash(RepoAuthType rat) { return rat.hash(); }
 205
 206   static size_t hash(const IterTabEnt& iterTab) {
 207     auto const partial = folly::hash::hash_128_to_64(
 208       iterTab.kind, iterTab.id
 209     );
 210     return static_cast<size_t>(
 211       folly::hash::hash_128_to_64(iterTab.local, partial)
 212     );
 213   }
 214
 215   static size_t hash(MKey mkey) {
 216     return HPHP::hash_int64_pair(mkey.mcode, mkey.int64);
 217   }
 218
 219   template<class T>
 220   static size_t hash(const CompactVector<T>& v) {
 221     return v.empty() ? 0 : v.size() ^ hash(v.front());
 222   }
 223
 224   static size_t hash(std::pair<LSString,BlockId> kv) {
 225     return HPHP::hash_int64_pair(kv.first->hash(), kv.second);
 226   }
 227
 228   static size_t hash(LocalRange range) {
 229     return HPHP::hash_int64_pair(range.first, range.count);
 230   }
 231
 232   static size_t hash(FCallArgs fca) {
 233     uint64_t hash = HPHP::hash_int64_pair(fca.numArgs, fca.numRets);
 234     hash = HPHP::hash_int64_pair(hash, fca.flags);
 235     if (fca.byRefs) {
 236       auto const br = reinterpret_cast<char*>(fca.byRefs.get());
 237       auto const hash_br = hash_string_cs(br, (fca.numArgs + 7 / 8));
 238       hash = HPHP::hash_int64_pair(hash, hash_br);
 239     }
 240     hash = HPHP::hash_int64_pair(hash, fca.asyncEagerTarget);
 241     return static_cast<size_t>(hash);
 242   }
 243
 244   template<class T>
 245   static typename std::enable_if<
 246     std::is_enum<T>::value,
 247     size_t
 248   >::type hash(T t) {
 249     using U = typename std::underlying_type<T>::type;
 250     return std::hash<U>()(static_cast<U>(t));
 251   }
 252
 253   template<class T>
 254   static typename std::enable_if<
 255     !std::is_enum<T>::value,
 256     size_t
 257   >::type hash(const T& t) { return std::hash<T>()(t); }
 258 };
 259
 260 /*
 261  * Hash operand wrapper.
 262  */
 263 template<typename T, typename S>
 264 struct hash_operand { const T& val; S type; };
 265
 266 // this template isn't really needed. its a workaround for T44007494
 267 template<typename S> struct hash_operand<void*, S> { void* const val; S type; };
 268
 269 /*
 270  * Hash T using H::operator() if it is compatible, else fall back to
 271  * hasher_impl (e.g., if H := hasher_default).
 272  */
 273 template<typename T, typename S, class H>
 274 auto hash(const hash_operand<T,S>& t, H h) -> decltype(h(t.val)) {
 275   return h(t.val);
 276 }
 277 template<typename T, typename S, class H>
 278 auto hash(const hash_operand<T,S>& t, H h) -> decltype(h(t.val, t.type)) {
 279   return h(t.val, t.type);
 280 }
 281 template<typename T, typename S, typename... Unused>
 282 typename std::enable_if<sizeof...(Unused) == 1, size_t>::type
 283 hash(const hash_operand<T,S>& t, Unused...) {
 284   return hasher_impl::hash(t.val);
 285 }
 286
 287 /*
 288  * Clone of folly::hash::hash_combine_generic.
 289  */
 290 template <class H>
 291 size_t hash_combine(H /*h*/) {
 292   return 0;
 293 }
 294
 295 template<class H, typename T, typename... Ts>
 296 size_t hash_combine(H h, const T& t, const Ts&... ts) {
 297   auto const seed = size_t{hash(t, h)};
 298   if (sizeof...(ts) == 0) return seed;
 299
 300   auto const remainder = hash_combine(h, ts...);
 301   return static_cast<size_t>(folly::hash::hash_128_to_64(seed, remainder));
 302 }
 303
 304 /*
 305  * Trivial equality overrides, which will cause bytecodes to compare via
 306  * operator==() on the various immediate types.
 307  */
 308 struct eq_default {};
 309
 310 /*
 311  * Equality operand wrapper.
 312  */
 313 template<typename T, typename S>
 314 struct eq_operand { const T& l; const T& r; S type; };
 315
 316 // this template isn't really needed. its a workaround for T44007494
 317 template<typename S> struct eq_operand<void*, S> {
 318   void* const l; void* const r; S type;
 319 };
 320
 321 /*
 322  * Compare two values, using E::operator() if it exists, else the default
 323  * operator==.
 324  */
 325 template<typename T, typename S, class E>
 326 auto equals(const eq_operand<T,S>& t, E e) -> decltype(e(t.l, t.r)) {
 327   return e(t.l, t.r);
 328 }
 329 template<typename T, typename S, class E>
 330 auto equals(const eq_operand<T,S>& t, E e) -> decltype(e(t.l, t.r, t.type)) {
 331   return e(t.l, t.r, t.type);
 332 }
 333 template<typename T, typename S, typename... Unused>
 334 typename std::enable_if<sizeof...(Unused) == 1, bool>::type
 335 equals(const eq_operand<T,S>& t, Unused...) {
 336   return t.l == t.r;
 337 }
 338
 339 /*
 340  * Check if a list of eq_operands are pairwise-equal.
 341  */
 342 template <class E>
 343 bool eq_pairs(E /*e*/) {
 344   return true;
 345 }
 346
 347 template<class E, typename T, typename... Ts>
 348 bool eq_pairs(E e, const T& t, const Ts&... ts) {
 349   return equals(t, e) && (sizeof...(ts) == 0 || eq_pairs(e, ts...));
 350 }
 351
 352 }
 353
 354 //////////////////////////////////////////////////////////////////////
 355
 356 /*
 357  * Bytecode immediate type tags.
 358  */
 359 namespace imm {
 360 #define ARGTYPE(name, type)     enum class name : uint8_t {};
 361 #define ARGTYPEVEC(name, type)  enum class name : uint8_t {};
 362   ARGTYPES
 363 #undef ARGTYPE
 364 #undef ARGTYPEVEC
 365 }
 366
 367 #define IMM_ID_BLA      BLA
 368 #define IMM_ID_SLA      SLA
 369 #define IMM_ID_ILA      ILA
 370 #define IMM_ID_I32LA    I32LA
 371 #define IMM_ID_IVA      IVA
 372 #define IMM_ID_I64A     I64A
 373 #define IMM_ID_LA       LA
 374 #define IMM_ID_IA       IA
 375 #define IMM_ID_CAR      CAR
 376 #define IMM_ID_CAW      CAW
 377 #define IMM_ID_DA       DA
 378 #define IMM_ID_SA       SA
 379 #define IMM_ID_RATA     RATA
 380 #define IMM_ID_AA       AA
 381 #define IMM_ID_BA       BA
 382 #define IMM_ID_OA(type) OA
 383 #define IMM_ID_VSA      VSA
 384 #define IMM_ID_KA       KA
 385 #define IMM_ID_LAR      LAR
 386 #define IMM_ID_FCA      FCA
 387
 388 #define IMM_TY_BLA      SwitchTab
 389 #define IMM_TY_SLA      SSwitchTab
 390 #define IMM_TY_ILA      IterTab
 391 #define IMM_TY_I32LA    CompactVector<uint32_t>
 392 #define IMM_TY_IVA      uint32_t
 393 #define IMM_TY_I64A     int64_t
 394 #define IMM_TY_LA       LocalId
 395 #define IMM_TY_IA       IterId
 396 #define IMM_TY_CAR      ClsRefSlotId
 397 #define IMM_TY_CAW      ClsRefSlotId
 398 #define IMM_TY_DA       double
 399 #define IMM_TY_SA       LSString
 400 #define IMM_TY_RATA     RepoAuthType
 401 #define IMM_TY_AA       SArray
 402 #define IMM_TY_BA       BlockId
 403 #define IMM_TY_OA(type) type
 404 #define IMM_TY_VSA      CompactVector<LSString>
 405 #define IMM_TY_KA       MKey
 406 #define IMM_TY_LAR      LocalRange
 407 #define IMM_TY_FCA      FCallArgs
 408
 409 #define IMM_NAME_BLA(n)     targets
 410 #define IMM_NAME_SLA(n)     targets
 411 #define IMM_NAME_ILA(n)     iterTab
 412 #define IMM_NAME_I32LA(n)   argv
 413 #define IMM_NAME_IVA(n)     arg##n
 414 #define IMM_NAME_I64A(n)    arg##n
 415 #define IMM_NAME_LA(n)      loc##n
 416 #define IMM_NAME_IA(n)      iter##n
 417 #define IMM_NAME_CAR(n)     slot
 418 #define IMM_NAME_CAW(n)     slot
 419 #define IMM_NAME_DA(n)      dbl##n
 420 #define IMM_NAME_SA(n)      str##n
 421 #define IMM_NAME_RATA(n)    rat
 422 #define IMM_NAME_AA(n)      arr##n
 423 #define IMM_NAME_BA(n)      target##n
 424 #define IMM_NAME_OA_IMPL(n) subop##n
 425 #define IMM_NAME_OA(type)   IMM_NAME_OA_IMPL
 426 #define IMM_NAME_VSA(n)     keys
 427 #define IMM_NAME_KA(n)      mkey
 428 #define IMM_NAME_LAR(n)     locrange
 429 #define IMM_NAME_FCA(n)     fca
 430
 431 #define IMM_TARGETS_BLA(n)  for (auto& t : targets) f(t);
 432 #define IMM_TARGETS_SLA(n)  for (auto& kv : targets) f(kv.second);
 433 #define IMM_TARGETS_ILA(n)
 434 #define IMM_TARGETS_I32LA(n)
 435 #define IMM_TARGETS_IVA(n)
 436 #define IMM_TARGETS_I64A(n)
 437 #define IMM_TARGETS_LA(n)
 438 #define IMM_TARGETS_IA(n)
 439 #define IMM_TARGETS_CAR(n)
 440 #define IMM_TARGETS_CAW(n)
 441 #define IMM_TARGETS_DA(n)
 442 #define IMM_TARGETS_SA(n)
 443 #define IMM_TARGETS_RATA(n)
 444 #define IMM_TARGETS_AA(n)
 445 #define IMM_TARGETS_BA(n)      f(target##n);
 446 #define IMM_TARGETS_OA_IMPL(n)
 447 #define IMM_TARGETS_OA(type)   IMM_TARGETS_OA_IMPL
 448 #define IMM_TARGETS_VSA(n)
 449 #define IMM_TARGETS_KA(n)
 450 #define IMM_TARGETS_LAR(n)
 451 #define IMM_TARGETS_FCA(n)   if (fca.asyncEagerTarget != NoBlockId) { \
 452                                f(fca.asyncEagerTarget);               \
 453                              }
 454
 455 #define IMM_EXTRA_BLA
 456 #define IMM_EXTRA_SLA
 457 #define IMM_EXTRA_ILA
 458 #define IMM_EXTRA_I32LA
 459 #define IMM_EXTRA_IVA
 460 #define IMM_EXTRA_I64A
 461 #define IMM_EXTRA_LA
 462 #define IMM_EXTRA_IA
 463 #define IMM_EXTRA_CAR       using has_car_flag = std::true_type;
 464 #define IMM_EXTRA_CAW       using has_caw_flag = std::true_type;
 465 #define IMM_EXTRA_DA
 466 #define IMM_EXTRA_SA
 467 #define IMM_EXTRA_RATA
 468 #define IMM_EXTRA_AA
 469 #define IMM_EXTRA_BA
 470 #define IMM_EXTRA_OA(x)
 471 #define IMM_EXTRA_VSA
 472 #define IMM_EXTRA_KA
 473 #define IMM_EXTRA_LAR
 474 #define IMM_EXTRA_FCA
 475
 476 #define IMM_MEM(which, n)          IMM_TY_##which IMM_NAME_##which(n)
 477 #define IMM_MEM_NA
 478 #define IMM_MEM_ONE(x)             IMM_MEM(x, 1);
 479 #define IMM_MEM_TWO(x, y)          IMM_MEM(x, 1); IMM_MEM(y, 2);
 480 #define IMM_MEM_THREE(x, y, z)     IMM_MEM(x, 1); IMM_MEM(y, 2); \
 481                                    IMM_MEM(z, 3);
 482 #define IMM_MEM_FOUR(x, y, z, l)   IMM_MEM(x, 1); IMM_MEM(y, 2); \
 483                                    IMM_MEM(z, 3); IMM_MEM(l, 4);
 484 #define IMM_MEM_FIVE(x, y, z, l, m) IMM_MEM(x, 1); IMM_MEM(y, 2); \
 485                                    IMM_MEM(z, 3); IMM_MEM(l, 4); \
 486                                    IMM_MEM(m, 5);
 487
 488 #define IMM_EQ_WRAP(e, ...)       detail::eq_pairs(e, __VA_ARGS__)
 489 #define IMM_EQ(which, n)          detail::eq_operand<     \
 490                                     IMM_TY_##which,       \
 491                                     imm::IMM_ID_##which   \
 492                                   > { \
 493                                     IMM_NAME_##which(n),  \
 494                                     o.IMM_NAME_##which(n) \
 495                                   }
 496 #define IMM_EQ_NA                 detail::eq_operand<void*,imm::NA> { 0, 0 }
 497 #define IMM_EQ_ONE(x)             IMM_EQ(x, 1)
 498 #define IMM_EQ_TWO(x, y)          IMM_EQ_ONE(x), IMM_EQ(y, 2)
 499 #define IMM_EQ_THREE(x, y, z)     IMM_EQ_TWO(x, y), IMM_EQ(z, 3)
 500 #define IMM_EQ_FOUR(x, y, z, l)   IMM_EQ_THREE(x, y, z), IMM_EQ(l, 4)
 501 #define IMM_EQ_FIVE(x, y, z, l, m) IMM_EQ_FOUR(x, y, z, l), IMM_EQ(m, 5)
 502
 503 #define IMM_HASH_WRAP(h, ...)       detail::hash_combine(h, __VA_ARGS__)
 504 #define IMM_HASH(which, n)          detail::hash_operand<     \
 505                                       IMM_TY_##which,         \
 506                                       imm::IMM_ID_##which     \
 507                                     > { IMM_NAME_##which(n) }
 508 #define IMM_HASH_NA                 detail::hash_operand<void*,imm::NA> { 0 }
 509 #define IMM_HASH_ONE(x)             IMM_HASH(x, 1)
 510 #define IMM_HASH_TWO(x, y)          IMM_HASH_ONE(x), IMM_HASH(y, 2)
 511 #define IMM_HASH_THREE(x, y, z)     IMM_HASH_TWO(x, y), IMM_HASH(z, 3)
 512 #define IMM_HASH_FOUR(x, y, z, l)   IMM_HASH_THREE(x, y, z), IMM_HASH(l, 4)
 513 #define IMM_HASH_FIVE(x, y, z, l, m) IMM_HASH_FOUR(x, y, z, l), IMM_HASH(m, 5)
 514
 515 #define IMM_TARGETS_NA
 516 #define IMM_TARGETS_ONE(x)          IMM_TARGETS_##x(1)
 517 #define IMM_TARGETS_TWO(x,y)        IMM_TARGETS_ONE(x) IMM_TARGETS_##y(2)
 518 #define IMM_TARGETS_THREE(x,y,z)    IMM_TARGETS_TWO(x,y) IMM_TARGETS_##z(3)
 519 #define IMM_TARGETS_FOUR(x,y,z,l)   IMM_TARGETS_THREE(x,y,z) IMM_TARGETS_##l(4)
 520 #define IMM_TARGETS_FIVE(x,y,z,l,m) IMM_TARGETS_FOUR(x,y,z,l) IMM_TARGETS_##m(5)
 521
 522 #define IMM_EXTRA_NA
 523 #define IMM_EXTRA_ONE(x)           IMM_EXTRA_##x
 524 #define IMM_EXTRA_TWO(x,y)         IMM_EXTRA_ONE(x)       IMM_EXTRA_ONE(y)
 525 #define IMM_EXTRA_THREE(x,y,z)     IMM_EXTRA_TWO(x,y)     IMM_EXTRA_ONE(z)
 526 #define IMM_EXTRA_FOUR(x,y,z,l)    IMM_EXTRA_THREE(x,y,z) IMM_EXTRA_ONE(l)
 527 #define IMM_EXTRA_FIVE(x,y,z,l,m)  IMM_EXTRA_FOUR(x,y,z,l) IMM_EXTRA_ONE(m)
 528
 529 #define IMM_CTOR(which, n)         IMM_TY_##which IMM_NAME_##which(n)
 530 #define IMM_CTOR_NA
 531 #define IMM_CTOR_ONE(x)            IMM_CTOR(x, 1)
 532 #define IMM_CTOR_TWO(x, y)         IMM_CTOR(x, 1), IMM_CTOR(y, 2)
 533 #define IMM_CTOR_THREE(x, y, z)    IMM_CTOR(x, 1), IMM_CTOR(y, 2), \
 534                                    IMM_CTOR(z, 3)
 535 #define IMM_CTOR_FOUR(x, y, z, l)  IMM_CTOR(x, 1), IMM_CTOR(y, 2), \
 536                                    IMM_CTOR(z, 3), IMM_CTOR(l, 4)
 537 #define IMM_CTOR_FIVE(x, y, z, l, m) IMM_CTOR(x, 1), IMM_CTOR(y, 2),     \
 538                                      IMM_CTOR(z, 3), IMM_CTOR(l, 4),     \
 539                                      IMM_CTOR(m, 5)
 540
 541 #define IMM_INIT(which, n)         IMM_NAME_##which(n) \
 542                                      ( std::move(IMM_NAME_##which(n)) )
 543 #define IMM_INIT_NA
 544 #define IMM_INIT_ONE(x)            : IMM_INIT(x, 1)
 545 #define IMM_INIT_TWO(x, y)         : IMM_INIT(x, 1), IMM_INIT(y, 2)
 546 #define IMM_INIT_THREE(x, y, z)    : IMM_INIT(x, 1), IMM_INIT(y, 2), \
 547                                      IMM_INIT(z, 3)
 548 #define IMM_INIT_FOUR(x, y, z, l)  : IMM_INIT(x, 1), IMM_INIT(y, 2), \
 549                                      IMM_INIT(z, 3), IMM_INIT(l, 4)
 550 #define IMM_INIT_FIVE(x, y, z, l, m) : IMM_INIT(x, 1), IMM_INIT(y, 2),   \
 551                                        IMM_INIT(z, 3), IMM_INIT(l, 4),   \
 552                                        IMM_INIT(m, 5)
 553
 554 #define POP_UV  if (i == 0) return Flavor::U
 555 #define POP_CV  if (i == 0) return Flavor::C
 556 #define POP_VV  if (i == 0) return Flavor::V
 557 #define POP_CUV if (i == 0) return Flavor::CU
 558
 559 #define POP_NOV             uint32_t numPop() const { return 0; } \
 560                             Flavor popFlavor(uint32_t) const { not_reached(); }
 561
 562 #define POP_ONE(x)          uint32_t numPop() const { return 1; } \
 563                             Flavor popFlavor(uint32_t i) const {  \
 564                               POP_##x; not_reached();             \
 565                             }
 566
 567 #define POP_TWO(x, y)       uint32_t numPop() const { return 2; }   \
 568                             Flavor popFlavor(uint32_t i) const {    \
 569                               POP_##x; --i; POP_##y; not_reached(); \
 570                             }
 571
 572 #define POP_THREE(x, y, z)  uint32_t numPop() const { return 3; }   \
 573                             Flavor popFlavor(uint32_t i) const {    \
 574                               POP_##x; --i; POP_##y; --i; POP_##z;  \
 575                               not_reached();                        \
 576                             }
 577
 578 #define POP_MFINAL  uint32_t numPop() const { return arg1; } \
 579                     Flavor popFlavor(uint32_t) const { not_reached(); }
 580
 581 #define POP_C_MFINAL(n) uint32_t numPop() const { return arg1 + n; } \
 582                      Flavor popFlavor(uint32_t) const { not_reached(); }
 583
 584 #define POP_CMANY   uint32_t numPop() const { return arg1; }  \
 585                     Flavor popFlavor(uint32_t i) const {      \
 586                       assert(i < numPop());                   \
 587                       return Flavor::C;                       \
 588                     }
 589
 590 #define POP_SMANY   uint32_t numPop() const { return keys.size(); }  \
 591                     Flavor popFlavor(uint32_t i) const {      \
 592                       assert(i < numPop());                   \
 593                       return Flavor::C;                       \
 594                     }
 595
 596 #define POP_CUMANY  uint32_t numPop() const { return arg1; }  \
 597                     Flavor popFlavor(uint32_t i) const {      \
 598                       assert(i < numPop());                   \
 599                       return Flavor::CU;                      \
 600                     }
 601
 602 #define POP_CVUMANY uint32_t numPop() const { return arg1; }  \
 603                     Flavor popFlavor(uint32_t i) const {      \
 604                       assert(i < numPop());                   \
 605                       return Flavor::CVU;                     \
 606                     }
 607
 608 #define POP_FPUSH(nin, nobj)                                                   \
 609                     uint32_t numPop() const { return arg1 + nin + 3; }         \
 610                     Flavor popFlavor(uint32_t i) const {                       \
 611                       assert(i < numPop());                                    \
 612                       if (i < nin) return Flavor::C;                           \
 613                       i -= nin;                                                \
 614                       if (i < arg1) return Flavor::CV;                         \
 615                       i -= arg1;                                               \
 616                       if (i < 2) return Flavor::U;                             \
 617                       return nobj ? Flavor::C : Flavor::U;                     \
 618                     }
 619
 620 #define POP_FCALL   uint32_t numPop() const {                                  \
 621                       return fca.numArgs + (fca.hasUnpack() ? 1 : 0) +         \
 622                              fca.numRets - 1;                                  \
 623                     }                                                          \
 624                     Flavor popFlavor(uint32_t i) const {                       \
 625                       assert(i < numPop());                                    \
 626                       if (i == 0 && fca.hasUnpack()) return Flavor::C;         \
 627                       auto const cv = fca.numArgs + (fca.hasUnpack() ? 1 : 0); \
 628                       return i < cv ? Flavor::CV : Flavor::U;                  \
 629                     }
 630
 631 #define PUSH_NOV          uint32_t numPush() const { return 0; }
 632
 633 #define PUSH_ONE(x)       uint32_t numPush() const { return 1; }
 634
 635 #define PUSH_TWO(x, y)    uint32_t numPush() const { return 2; }
 636
 637 #define PUSH_FPUSH        uint32_t numPush() const { return arg1; }
 638 #define PUSH_FCALL        uint32_t numPush() const { return fca.numRets; }
 639
 640 #define FLAGS_NF
 641 #define FLAGS_TF
 642 #define FLAGS_CF
 643 #define FLAGS_FF
 644 #define FLAGS_PF bool has_unpack;
 645 #define FLAGS_CF_TF
 646 #define FLAGS_CF_FF
 647
 648 #define FLAGS_CTOR_NF
 649 #define FLAGS_CTOR_TF
 650 #define FLAGS_CTOR_CF
 651 #define FLAGS_CTOR_FF
 652 #define FLAGS_CTOR_PF ,bool hu
 653 #define FLAGS_CTOR_CF_TF
 654 #define FLAGS_CTOR_CF_FF
 655
 656 #define FLAGS_INIT_NF
 657 #define FLAGS_INIT_TF
 658 #define FLAGS_INIT_CF
 659 #define FLAGS_INIT_FF
 660 #define FLAGS_INIT_PF ,has_unpack(hu)
 661 #define FLAGS_INIT_CF_TF
 662 #define FLAGS_INIT_CF_FF
 663
 664 #define O(opcode, imms, inputs, outputs, flags) \
 665   struct opcode {                               \
 666     static constexpr Op op = Op::opcode;        \
 667     explicit opcode ( IMM_CTOR_##imms           \
 668                       FLAGS_CTOR_##flags)       \
 669       IMM_INIT_##imms                           \
 670       FLAGS_INIT_##flags                        \
 671     {}                                          \
 672                                                 \
 673     IMM_MEM_##imms                              \
 674     FLAGS_##flags                               \
 675     IMM_EXTRA_##imms                            \
 676     POP_##inputs                                \
 677     PUSH_##outputs                              \
 678                                                 \
 679     bool operator==(const opcode& o) const {    \
 680       return equals(o, detail::eq_default{});   \
 681     }                                           \
 682                                                 \
 683     bool operator!=(const opcode& o) const {    \
 684       return !(*this == o);                     \
 685     }                                           \
 686                                                 \
 687     template<class E>                           \
 688     bool equals(const opcode& o, E e) const {   \
 689       return IMM_EQ_WRAP(e, IMM_EQ_##imms);     \
 690     }                                           \
 691                                                 \
 692     size_t hash() const {                       \
 693       return IMM_HASH_WRAP(                     \
 694         detail::hasher_default{},               \
 695         IMM_HASH_##imms);                       \
 696     }                                           \
 697                                                 \
 698     template<class H>                           \
 699     size_t hash(H h) const {                    \
 700       return IMM_HASH_WRAP(h, IMM_HASH_##imms); \
 701     }                                           \
 702                                                 \
 703     template <typename F>                       \
 704     void forEachTarget(F&& f) {                 \
 705       IMM_TARGETS_##imms                        \
 706     }                                           \
 707     template <typename F>                       \
 708     void forEachTarget(F&& f) const {           \
 709       IMM_TARGETS_##imms                        \
 710     }                                           \
 711   };
 712 OPCODES
 713 #undef O
 714
 715 #undef FLAGS_NA
 716 #undef FLAGS_TF
 717 #undef FLAGS_CF
 718 #undef FLAGS_FF
 719 #undef FLAGS_PF
 720 #undef FLAGS_CF_TF
 721 #undef FLAGS_CF_FF
 722
 723 #undef FLAGS_CTOR_NA
 724 #undef FLAGS_CTOR_TF
 725 #undef FLAGS_CTOR_CF
 726 #undef FLAGS_CTOR_FF
 727 #undef FLAGS_CTOR_PF
 728 #undef FLAGS_CTOR_CF_TF
 729 #undef FLAGS_CTOR_CF_FF
 730
 731 #undef FLAGS_INIT_NA
 732 #undef FLAGS_INIT_TF
 733 #undef FLAGS_INIT_CF
 734 #undef FLAGS_INIT_FF
 735 #undef FLAGS_INIT_PF
 736 #undef FLAGS_INIT_CF_TF
 737 #undef FLAGS_INIT_CF_FF
 738
 739 #undef PUSH_NOV
 740 #undef PUSH_ONE
 741 #undef PUSH_TWO
 742 #undef PUSH_FPUSH
 743 #undef PUSH_FCALL
 744
 745 #undef POP_UV
 746 #undef POP_CV
 747 #undef POP_VV
 748
 749 #undef POP_NOV
 750 #undef POP_ONE
 751 #undef POP_TWO
 752 #undef POP_THREE
 753 #undef POP_MFINAL
 754 #undef POP_C_MFINAL
 755 #undef POP_CMANY
 756 #undef POP_SMANY
 757 #undef POP_CUMANY
 758 #undef POP_CVUMANY
 759 #undef POP_FPUSH
 760 #undef POP_FCALL
 761
 762 #undef IMM_TY_MA
 763 #undef IMM_TY_BLA
 764 #undef IMM_TY_SLA
 765 #undef IMM_TY_ILA
 766 #undef IMM_TY_I32LA
 767 #undef IMM_TY_IVA
 768 #undef IMM_TY_I64A
 769 #undef IMM_TY_LA
 770 #undef IMM_TY_IA
 771 #undef IMM_TY_CAR
 772 #undef IMM_TY_CAW
 773 #undef IMM_TY_DA
 774 #undef IMM_TY_SA
 775 #undef IMM_TY_RATA
 776 #undef IMM_TY_AA
 777 #undef IMM_TY_BA
 778 #undef IMM_TY_OA
 779 #undef IMM_TY_VSA
 780 #undef IMM_TY_KA
 781 #undef IMM_TY_LAR
 782 #undef IMM_TY_FCA
 783
 784 // These are deliberately not undefined, so they can be used in other
 785 // places.
 786 // #undef IMM_NAME_BLA
 787 // #undef IMM_NAME_SLA
 788 // #undef IMM_NAME_ILA
 789 // #undef IMM_NAME_I32LA
 790 // #undef IMM_NAME_IVA
 791 // #undef IMM_NAME_I64A
 792 // #undef IMM_NAME_LA
 793 // #undef IMM_NAME_IA
 794 // #undef IMM_NAME_CAR
 795 // #undef IMM_NAME_CAW
 796 // #undef IMM_NAME_DA
 797 // #undef IMM_NAME_SA
 798 // #undef IMM_NAME_RATA
 799 // #undef IMM_NAME_AA
 800 // #undef IMM_NAME_BA
 801 // #undef IMM_NAME_OA
 802 // #undef IMM_NAME_OA_IMPL
 803 // #undef IMM_NAME_LAR
 804 // #undef IMM_NAME_FCA
 805
 806 #undef IMM_TARGETS_BLA
 807 #undef IMM_TARGETS_SLA
 808 #undef IMM_TARGETS_ILA
 809 #undef IMM_TARGETS_I32LA
 810 #undef IMM_TARGETS_IVA
 811 #undef IMM_TARGETS_I64A
 812 #undef IMM_TARGETS_LA
 813 #undef IMM_TARGETS_IA
 814 #undef IMM_TARGETS_CAR
 815 #undef IMM_TARGETS_CAW
 816 #undef IMM_TARGETS_DA
 817 #undef IMM_TARGETS_SA
 818 #undef IMM_TARGETS_RATA
 819 #undef IMM_TARGETS_AA
 820 #undef IMM_TARGETS_BA
 821 #undef IMM_TARGETS_OA
 822 #undef IMM_TARGETS_KA
 823 #undef IMM_TARGETS_LAR
 824 #undef IMM_TARGETS_FCA
 825
 826 #undef IMM_TARGETS_NA
 827 #undef IMM_TARGETS_ONE
 828 #undef IMM_TARGETS_TWO
 829 #undef IMM_TARGETS_THREE
 830 #undef IMM_TARGETS_FOUR
 831 #undef IMM_TARGETS_FIVE
 832
 833 #undef IMM_EXTRA_BLA
 834 #undef IMM_EXTRA_SLA
 835 #undef IMM_EXTRA_ILA
 836 #undef IMM_EXTRA_I32LA
 837 #undef IMM_EXTRA_IVA
 838 #undef IMM_EXTRA_I64A
 839 #undef IMM_EXTRA_LA
 840 #undef IMM_EXTRA_IA
 841 #undef IMM_EXTRA_CAR
 842 #undef IMM_EXTRA_CAW
 843 #undef IMM_EXTRA_DA
 844 #undef IMM_EXTRA_SA
 845 #undef IMM_EXTRA_RATA
 846 #undef IMM_EXTRA_AA
 847 #undef IMM_EXTRA_BA
 848 #undef IMM_EXTRA_OA
 849 #undef IMM_EXTRA_KA
 850 #undef IMM_EXTRA_LAR
 851 #undef IMM_EXTRA_FCA
 852
 853 #undef IMM_MEM
 854 #undef IMM_MEM_NA
 855 #undef IMM_MEM_ONE
 856 #undef IMM_MEM_TWO
 857 #undef IMM_MEM_THREE
 858 #undef IMM_MEM_FOUR
 859 #undef IMM_MEM_FIVE
 860
 861 #undef IMM_EQ
 862 #undef IMM_EQ_NA
 863 #undef IMM_EQ_ONE
 864 #undef IMM_EQ_TWO
 865 #undef IMM_EQ_THREE
 866 #undef IMM_EQ_FOUR
 867 #undef IMM_EQ_FIVE
 868
 869 #undef IMM_HASH
 870 #undef IMM_HASH_DO
 871 #undef IMM_HASH_NA
 872 #undef IMM_HASH_ONE
 873 #undef IMM_HASH_TWO
 874 #undef IMM_HASH_THREE
 875 #undef IMM_HASH_FOUR
 876 #undef IMM_HASH_FIVE
 877
 878 #undef IMM_CTOR
 879 #undef IMM_CTOR_NA
 880 #undef IMM_CTOR_ONE
 881 #undef IMM_CTOR_TWO
 882 #undef IMM_CTOR_THREE
 883 #undef IMM_CTOR_FOUR
 884 #undef IMM_CTOR_FIVE
 885
 886 #undef IMM_INIT
 887 #undef IMM_INIT_NA
 888 #undef IMM_INIT_ONE
 889 #undef IMM_INIT_TWO
 890 #undef IMM_INIT_THREE
 891 #undef IMM_INIT_FOUR
 892
 893 }
 894
 895 //////////////////////////////////////////////////////////////////////
 896
 897 /*
 898  * Bytecode is a tagged-union that can hold any HHBC opcode struct
 899  * defined above.  You can visit a bytecode with a static_visitor
 900  * using visit(), defined below.
 901  *
 902  * Each Bytecode also carries a corresponding SrcLoc that indicates
 903  * which line of PHP code the bytecode was generated for.
 904  */
 905 struct Bytecode {
 906   // Default construction creates a Nop.
 907   Bytecode()
 908     : op(Op::Nop)
 909     , Nop(bc::Nop{})
 910   {}
 911
 912 #define O(opcode, ...)                          \
 913   /* implicit */ Bytecode(bc::opcode data)      \
 914     : op(Op::opcode)                            \
 915   {                                             \
 916     new (&opcode) bc::opcode(std::move(data));  \
 917   }
 918
 919   OPCODES
 920
 921 #undef O
 922
 923   // Note: assuming bc::Nop is empty and has trivial dtor/ctor.
 924
 925   Bytecode(const Bytecode& o) : op(Op::Nop) { *this = o; }
 926   Bytecode(Bytecode&& o) noexcept : op(Op::Nop) { *this = std::move(o); }
 927
 928   Bytecode& operator=(const Bytecode& o) {
 929     destruct();
 930     op = Op::Nop;
 931     srcLoc = o.srcLoc;
 932 #define O(opcode, ...) \
 933     case Op::opcode: new (&opcode) bc::opcode(o.opcode); break;
 934     switch (o.op) { OPCODES }
 935 #undef O
 936     op = o.op;
 937     return *this;
 938   }
 939
 940   Bytecode& operator=(Bytecode&& o) {
 941     destruct();
 942     srcLoc = o.srcLoc;
 943 #define O(opcode, ...) \
 944     case Op::opcode: new (&opcode) bc::opcode(std::move(o.opcode)); break;
 945     switch (o.op) { OPCODES }
 946 #undef O
 947     op = o.op;
 948     return *this;
 949   }
 950
 951   ~Bytecode() { destruct(); }
 952
 953   uint32_t numPop() const {
 954 #define O(opcode, ...) \
 955     case Op::opcode: return opcode.numPop();
 956     switch (op) { OPCODES }
 957 #undef O
 958     not_reached();
 959   }
 960
 961   Flavor popFlavor(uint32_t i) const {
 962 #define O(opcode, ...) \
 963     case Op::opcode: return opcode.popFlavor(i);
 964     switch (op) { OPCODES }
 965 #undef O
 966     not_reached();
 967   }
 968
 969   uint32_t numPush() const {
 970 #define O(opcode, ...) \
 971     case Op::opcode: return opcode.numPush();
 972     switch (op) { OPCODES }
 973 #undef O
 974     not_reached();
 975   }
 976
 977   template <typename F>
 978   void forEachTarget(F&& f) const {
 979 #define O(opcode, ...) \
 980     case Op::opcode: return opcode.forEachTarget(std::forward<F>(f));
 981     switch (op) { OPCODES }
 982 #undef O
 983     not_reached();
 984   }
 985
 986   template <typename F>
 987   void forEachTarget(F&& f) {
 988 #define O(opcode, ...) \
 989     case Op::opcode: return opcode.forEachTarget(std::forward<F>(f));
 990     switch (op) { OPCODES }
 991 #undef O
 992     not_reached();
 993   }
 994
 995   Op op;
 996   int32_t srcLoc{-1};
 997
 998 #define O(opcode, ...) bc::opcode opcode;
 999   union { OPCODES };
1000 #undef O
1001
1002 private:
1003   void destruct() {
1004     switch (op) {
1005 #define O(opcode, ...)                          \
1006       case Op::opcode:                          \
1007         { typedef bc::opcode X;                 \
1008           this->opcode.~X(); }                  \
1009         break;
1010       OPCODES
1011 #undef O
1012     }
1013   }
1014 };
1015
1016 //////////////////////////////////////////////////////////////////////
1017
1018 inline bool operator==(const Bytecode& a, const Bytecode& b) {
1019   if (a.op != b.op) return false;
1020 #define O(opcode, ...) case Op::opcode: return a.opcode == b.opcode;
1021   switch (a.op) { OPCODES }
1022 #undef O
1023   not_reached();
1024 }
1025
1026 inline bool operator!=(const Bytecode& a, const Bytecode& b) {
1027   return !(a == b);
1028 }
1029
1030 template<class E>
1031 inline bool equals(const Bytecode& a, const Bytecode& b, E equals) {
1032   if (a.op != b.op) return false;
1033 #define O(opcode, ...)  \
1034   case Op::opcode: return a.opcode.equals(b.opcode, equals);
1035   switch (a.op) { OPCODES }
1036 #undef O
1037   not_reached();
1038 }
1039
1040 template<class H>
1041 inline size_t hash(const Bytecode& b, H hasher) {
1042   auto hash = 14695981039346656037ULL;
1043   auto o = static_cast<size_t>(b.op);
1044   hash ^= o;
1045 #define O(opcode, ...)  \
1046   case Op::opcode:      \
1047     return folly::hash::hash_combine(b.opcode.hash(hasher), hash);
1048   switch (b.op) { OPCODES }
1049 #undef O
1050   not_reached();
1051 }
1052
1053 inline size_t hash(const Bytecode& b) {
1054   return hash(b, bc::detail::hasher_default{});
1055 }
1056
1057 //////////////////////////////////////////////////////////////////////
1058
1059 /*
1060  * Helper for making a Bytecode with a given srcLoc.
1061  *
1062  * Ex:
1063  *    auto b = bc_with_loc(something.srcLoc, bc::Nop {});
1064  */
1065 template<class T> Bytecode bc_with_loc(int32_t loc, const T& t) {
1066   Bytecode b = t;
1067   b.srcLoc = loc;
1068   return b;
1069 }
1070
1071 //////////////////////////////////////////////////////////////////////
1072
1073 /*
1074  * Visit a bytecode using a StaticVisitor, similar to
1075  * boost::apply_visitor or match().
1076  *
1077  * The `v' argument should be a function object that accepts a call
1078  * operator for all the bc::Foo types. Its result type should be
1079  * independent of bytecode, but may vary with constness.
1080  */
1081 template<class Visit>
1082 auto visit(Bytecode& b, Visit v) {
1083 #define O(opcode, ...) case Op::opcode: return v(b.opcode);
1084   switch (b.op) { OPCODES }
1085 #undef O
1086   not_reached();
1087 }
1088
1089 template<class Visit>
1090 auto visit(const Bytecode& b, Visit v) {
1091 #define O(opcode, ...) case Op::opcode: return v(b.opcode);
1092   switch (b.op) { OPCODES }
1093 #undef O
1094   not_reached();
1095 }
1096
1097 //////////////////////////////////////////////////////////////////////
1098
1099 struct ReadClsRefSlotVisitor {
1100   ReadClsRefSlotVisitor() {}
1101
1102   template<typename T>
1103   auto fun(T&, int) const { return NoClsRefSlotId; }
1104
1105   template<typename T>
1106   auto fun(T& t, bool) const -> decltype(typename T::has_car_flag{},t.slot) {
1107     return t.slot;
1108   }
1109
1110   template<typename T>
1111   ClsRefSlotId operator()(T& t) const { return fun(t, true); }
1112 };
1113
1114 struct WriteClsRefSlotVisitor {
1115   template<typename T>
1116   auto fun(T&, int) const { return NoClsRefSlotId; }
1117
1118   template<typename T>
1119   auto fun(T& t, bool) const -> decltype(typename T::has_caw_flag{},t.slot) {
1120     return t.slot;
1121   }
1122
1123   template<typename T>
1124   ClsRefSlotId operator()(T& t) const { return fun(t, true); }
1125 };
1126
1127 //////////////////////////////////////////////////////////////////////
1128
1129 }
1130
1131 }
1132
1133 #endif