1 // Copyright 2014 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_COMPILER_COMMON_OPERATOR_H_
6 #define V8_COMPILER_COMMON_OPERATOR_H_
7
8 #include "src/base/compiler-specific.h"
9 #include "src/compiler/frame-states.h"
10 #include "src/deoptimize-reason.h"
11 #include "src/globals.h"
12 #include "src/machine-type.h"
13 #include "src/reloc-info.h"
14 #include "src/vector-slot-pair.h"
15 #include "src/zone/zone-containers.h"
16 #include "src/zone/zone-handle-set.h"
17
18 namespace v8 {
19 namespace internal {
20 namespace compiler {
21
22 // Forward declarations.
23 class CallDescriptor;
24 struct CommonOperatorGlobalCache;
25 class Operator;
26 class Type;
27 class Node;
28
29 // Prediction hint for branches.
30 enum class BranchHint : uint8_t { kNone, kTrue, kFalse };
31
NegateBranchHint(BranchHint hint)32 inline BranchHint NegateBranchHint(BranchHint hint) {
33 switch (hint) {
34 case BranchHint::kNone:
35 return hint;
36 case BranchHint::kTrue:
37 return BranchHint::kFalse;
38 case BranchHint::kFalse:
39 return BranchHint::kTrue;
40 }
41 UNREACHABLE();
42 }
43
hash_value(BranchHint hint)44 inline size_t hash_value(BranchHint hint) { return static_cast<size_t>(hint); }
45
46 V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream&, BranchHint);
47
48 enum class IsSafetyCheck : uint8_t {
49 kCriticalSafetyCheck,
50 kSafetyCheck,
51 kNoSafetyCheck
52 };
53
54 // Get the more critical safety check of the two arguments.
55 IsSafetyCheck CombineSafetyChecks(IsSafetyCheck, IsSafetyCheck);
56
57 V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream&, IsSafetyCheck);
hash_value(IsSafetyCheck is_safety_check)58 inline size_t hash_value(IsSafetyCheck is_safety_check) {
59 return static_cast<size_t>(is_safety_check);
60 }
61
62 enum class TrapId : uint32_t {
63 #define DEF_ENUM(Name, ...) k##Name,
64 FOREACH_WASM_TRAPREASON(DEF_ENUM)
65 #undef DEF_ENUM
66 kInvalid
67 };
68
hash_value(TrapId id)69 inline size_t hash_value(TrapId id) { return static_cast<uint32_t>(id); }
70
71 std::ostream& operator<<(std::ostream&, TrapId trap_id);
72
73 TrapId TrapIdOf(const Operator* const op);
74
75 struct BranchOperatorInfo {
76 BranchHint hint;
77 IsSafetyCheck is_safety_check;
78 };
79
hash_value(const BranchOperatorInfo & info)80 inline size_t hash_value(const BranchOperatorInfo& info) {
81 return base::hash_combine(info.hint, info.is_safety_check);
82 }
83
84 V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream&, BranchOperatorInfo);
85
86 inline bool operator==(const BranchOperatorInfo& a,
87 const BranchOperatorInfo& b) {
88 return a.hint == b.hint && a.is_safety_check == b.is_safety_check;
89 }
90
91 V8_EXPORT_PRIVATE const BranchOperatorInfo& BranchOperatorInfoOf(
92 const Operator* const) V8_WARN_UNUSED_RESULT;
93 V8_EXPORT_PRIVATE BranchHint BranchHintOf(const Operator* const)
94 V8_WARN_UNUSED_RESULT;
95
96 // Helper function for return nodes, because returns have a hidden value input.
97 int ValueInputCountOfReturn(Operator const* const op);
98
99 // Parameters for the {Deoptimize} operator.
100 class DeoptimizeParameters final {
101 public:
DeoptimizeParameters(DeoptimizeKind kind,DeoptimizeReason reason,VectorSlotPair const & feedback,IsSafetyCheck is_safety_check)102 DeoptimizeParameters(DeoptimizeKind kind, DeoptimizeReason reason,
103 VectorSlotPair const& feedback,
104 IsSafetyCheck is_safety_check)
105 : kind_(kind),
106 reason_(reason),
107 feedback_(feedback),
108 is_safety_check_(is_safety_check) {}
109
kind()110 DeoptimizeKind kind() const { return kind_; }
reason()111 DeoptimizeReason reason() const { return reason_; }
feedback()112 const VectorSlotPair& feedback() const { return feedback_; }
is_safety_check()113 IsSafetyCheck is_safety_check() const { return is_safety_check_; }
114
115 private:
116 DeoptimizeKind const kind_;
117 DeoptimizeReason const reason_;
118 VectorSlotPair const feedback_;
119 IsSafetyCheck is_safety_check_;
120 };
121
122 bool operator==(DeoptimizeParameters, DeoptimizeParameters);
123 bool operator!=(DeoptimizeParameters, DeoptimizeParameters);
124
125 size_t hast_value(DeoptimizeParameters p);
126
127 std::ostream& operator<<(std::ostream&, DeoptimizeParameters p);
128
129 DeoptimizeParameters const& DeoptimizeParametersOf(Operator const* const)
130 V8_WARN_UNUSED_RESULT;
131
132 IsSafetyCheck IsSafetyCheckOf(const Operator* op) V8_WARN_UNUSED_RESULT;
133
134 class SelectParameters final {
135 public:
136 explicit SelectParameters(MachineRepresentation representation,
137 BranchHint hint = BranchHint::kNone)
representation_(representation)138 : representation_(representation), hint_(hint) {}
139
representation()140 MachineRepresentation representation() const { return representation_; }
hint()141 BranchHint hint() const { return hint_; }
142
143 private:
144 const MachineRepresentation representation_;
145 const BranchHint hint_;
146 };
147
148 bool operator==(SelectParameters const&, SelectParameters const&);
149 bool operator!=(SelectParameters const&, SelectParameters const&);
150
151 size_t hash_value(SelectParameters const& p);
152
153 std::ostream& operator<<(std::ostream&, SelectParameters const& p);
154
155 V8_EXPORT_PRIVATE SelectParameters const& SelectParametersOf(
156 const Operator* const) V8_WARN_UNUSED_RESULT;
157
158 V8_EXPORT_PRIVATE CallDescriptor const* CallDescriptorOf(const Operator* const)
159 V8_WARN_UNUSED_RESULT;
160
161 V8_EXPORT_PRIVATE size_t ProjectionIndexOf(const Operator* const)
162 V8_WARN_UNUSED_RESULT;
163
164 V8_EXPORT_PRIVATE MachineRepresentation
165 PhiRepresentationOf(const Operator* const) V8_WARN_UNUSED_RESULT;
166
167 // The {IrOpcode::kParameter} opcode represents an incoming parameter to the
168 // function. This class bundles the index and a debug name for such operators.
169 class ParameterInfo final {
170 public:
ParameterInfo(int index,const char * debug_name)171 ParameterInfo(int index, const char* debug_name)
172 : index_(index), debug_name_(debug_name) {}
173
index()174 int index() const { return index_; }
debug_name()175 const char* debug_name() const { return debug_name_; }
176
177 private:
178 int index_;
179 const char* debug_name_;
180 };
181
182 std::ostream& operator<<(std::ostream&, ParameterInfo const&);
183
184 V8_EXPORT_PRIVATE int ParameterIndexOf(const Operator* const)
185 V8_WARN_UNUSED_RESULT;
186 const ParameterInfo& ParameterInfoOf(const Operator* const)
187 V8_WARN_UNUSED_RESULT;
188
189 struct ObjectStateInfo final : std::pair<uint32_t, int> {
ObjectStateInfofinal190 ObjectStateInfo(uint32_t object_id, int size)
191 : std::pair<uint32_t, int>(object_id, size) {}
object_idfinal192 uint32_t object_id() const { return first; }
sizefinal193 int size() const { return second; }
194 };
195 std::ostream& operator<<(std::ostream&, ObjectStateInfo const&);
196 size_t hash_value(ObjectStateInfo const& p);
197
198 struct TypedObjectStateInfo final
199 : std::pair<uint32_t, const ZoneVector<MachineType>*> {
TypedObjectStateInfofinal200 TypedObjectStateInfo(uint32_t object_id,
201 const ZoneVector<MachineType>* machine_types)
202 : std::pair<uint32_t, const ZoneVector<MachineType>*>(object_id,
203 machine_types) {}
object_idfinal204 uint32_t object_id() const { return first; }
machine_typesfinal205 const ZoneVector<MachineType>* machine_types() const { return second; }
206 };
207 std::ostream& operator<<(std::ostream&, TypedObjectStateInfo const&);
208 size_t hash_value(TypedObjectStateInfo const& p);
209
210 class RelocatablePtrConstantInfo final {
211 public:
212 enum Type { kInt32, kInt64 };
213
RelocatablePtrConstantInfo(int32_t value,RelocInfo::Mode rmode)214 RelocatablePtrConstantInfo(int32_t value, RelocInfo::Mode rmode)
215 : value_(value), rmode_(rmode), type_(kInt32) {}
RelocatablePtrConstantInfo(int64_t value,RelocInfo::Mode rmode)216 RelocatablePtrConstantInfo(int64_t value, RelocInfo::Mode rmode)
217 : value_(value), rmode_(rmode), type_(kInt64) {}
218
value()219 intptr_t value() const { return value_; }
rmode()220 RelocInfo::Mode rmode() const { return rmode_; }
type()221 Type type() const { return type_; }
222
223 private:
224 intptr_t value_;
225 RelocInfo::Mode rmode_;
226 Type type_;
227 };
228
229 bool operator==(RelocatablePtrConstantInfo const& lhs,
230 RelocatablePtrConstantInfo const& rhs);
231 bool operator!=(RelocatablePtrConstantInfo const& lhs,
232 RelocatablePtrConstantInfo const& rhs);
233
234 std::ostream& operator<<(std::ostream&, RelocatablePtrConstantInfo const&);
235
236 size_t hash_value(RelocatablePtrConstantInfo const& p);
237
238 // Used to define a sparse set of inputs. This can be used to efficiently encode
239 // nodes that can have a lot of inputs, but where many inputs can have the same
240 // value.
241 class SparseInputMask final {
242 public:
243 typedef uint32_t BitMaskType;
244
245 // The mask representing a dense input set.
246 static const BitMaskType kDenseBitMask = 0x0;
247 // The bits representing the end of a sparse input set.
248 static const BitMaskType kEndMarker = 0x1;
249 // The mask for accessing a sparse input entry in the bitmask.
250 static const BitMaskType kEntryMask = 0x1;
251
252 // The number of bits in the mask, minus one for the end marker.
253 static const int kMaxSparseInputs = (sizeof(BitMaskType) * kBitsPerByte - 1);
254
255 // An iterator over a node's sparse inputs.
256 class InputIterator final {
257 public:
InputIterator()258 InputIterator() {}
259 InputIterator(BitMaskType bit_mask, Node* parent);
260
parent()261 Node* parent() const { return parent_; }
real_index()262 int real_index() const { return real_index_; }
263
264 // Advance the iterator to the next sparse input. Only valid if the iterator
265 // has not reached the end.
266 void Advance();
267
268 // Get the current sparse input's real node value. Only valid if the
269 // current sparse input is real.
270 Node* GetReal() const;
271
272 // Get the current sparse input, returning either a real input node if
273 // the current sparse input is real, or the given {empty_value} if the
274 // current sparse input is empty.
Get(Node * empty_value)275 Node* Get(Node* empty_value) const {
276 return IsReal() ? GetReal() : empty_value;
277 }
278
279 // True if the current sparse input is a real input node.
280 bool IsReal() const;
281
282 // True if the current sparse input is an empty value.
IsEmpty()283 bool IsEmpty() const { return !IsReal(); }
284
285 // True if the iterator has reached the end of the sparse inputs.
286 bool IsEnd() const;
287
288 private:
289 BitMaskType bit_mask_;
290 Node* parent_;
291 int real_index_;
292 };
293
SparseInputMask(BitMaskType bit_mask)294 explicit SparseInputMask(BitMaskType bit_mask) : bit_mask_(bit_mask) {}
295
296 // Provides a SparseInputMask representing a dense input set.
Dense()297 static SparseInputMask Dense() { return SparseInputMask(kDenseBitMask); }
298
mask()299 BitMaskType mask() const { return bit_mask_; }
300
IsDense()301 bool IsDense() const { return bit_mask_ == SparseInputMask::kDenseBitMask; }
302
303 // Counts how many real values are in the sparse array. Only valid for
304 // non-dense masks.
305 int CountReal() const;
306
307 // Returns an iterator over the sparse inputs of {node}.
308 InputIterator IterateOverInputs(Node* node);
309
310 private:
311 //
312 // The sparse input mask has a bitmask specifying if the node's inputs are
313 // represented sparsely. If the bitmask value is 0, then the inputs are dense;
314 // otherwise, they should be interpreted as follows:
315 //
316 // * The bitmask represents which values are real, with 1 for real values
317 // and 0 for empty values.
318 // * The inputs to the node are the real values, in the order of the 1s from
319 // least- to most-significant.
320 // * The top bit of the bitmask is a guard indicating the end of the values,
321 // whether real or empty (and is not representative of a real input
322 // itself). This is used so that we don't have to additionally store a
323 // value count.
324 //
325 // So, for N 1s in the bitmask, there are N - 1 inputs into the node.
326 BitMaskType bit_mask_;
327 };
328
329 bool operator==(SparseInputMask const& lhs, SparseInputMask const& rhs);
330 bool operator!=(SparseInputMask const& lhs, SparseInputMask const& rhs);
331
332 class TypedStateValueInfo final {
333 public:
TypedStateValueInfo(ZoneVector<MachineType> const * machine_types,SparseInputMask sparse_input_mask)334 TypedStateValueInfo(ZoneVector<MachineType> const* machine_types,
335 SparseInputMask sparse_input_mask)
336 : machine_types_(machine_types), sparse_input_mask_(sparse_input_mask) {}
337
machine_types()338 ZoneVector<MachineType> const* machine_types() const {
339 return machine_types_;
340 }
sparse_input_mask()341 SparseInputMask sparse_input_mask() const { return sparse_input_mask_; }
342
343 private:
344 ZoneVector<MachineType> const* machine_types_;
345 SparseInputMask sparse_input_mask_;
346 };
347
348 bool operator==(TypedStateValueInfo const& lhs, TypedStateValueInfo const& rhs);
349 bool operator!=(TypedStateValueInfo const& lhs, TypedStateValueInfo const& rhs);
350
351 std::ostream& operator<<(std::ostream&, TypedStateValueInfo const&);
352
353 size_t hash_value(TypedStateValueInfo const& p);
354
355 // Used to mark a region (as identified by BeginRegion/FinishRegion) as either
356 // JavaScript-observable or not (i.e. allocations are not JavaScript observable
357 // themselves, but transitioning stores are).
358 enum class RegionObservability : uint8_t { kObservable, kNotObservable };
359
360 size_t hash_value(RegionObservability);
361
362 std::ostream& operator<<(std::ostream&, RegionObservability);
363
364 RegionObservability RegionObservabilityOf(Operator const*)
365 V8_WARN_UNUSED_RESULT;
366
367 std::ostream& operator<<(std::ostream& os,
368 const ZoneVector<MachineType>* types);
369
370 Type TypeGuardTypeOf(Operator const*) V8_WARN_UNUSED_RESULT;
371
372 int OsrValueIndexOf(Operator const*) V8_WARN_UNUSED_RESULT;
373
374 SparseInputMask SparseInputMaskOf(Operator const*) V8_WARN_UNUSED_RESULT;
375
376 ZoneVector<MachineType> const* MachineTypesOf(Operator const*)
377 V8_WARN_UNUSED_RESULT;
378
379 // The ArgumentsElementsState and ArgumentsLengthState can describe the layout
380 // for backing stores of arguments objects of various types:
381 //
382 // +------------------------------------+
383 // - kUnmappedArguments: | arg0, ... argK-1, argK, ... argN-1 | {length:N}
384 // +------------------------------------+
385 // +------------------------------------+
386 // - kMappedArguments: | hole, ... hole, argK, ... argN-1 | {length:N}
387 // +------------------------------------+
388 // +------------------+
389 // - kRestParameter: | argK, ... argN-1 | {length:N-K}
390 // +------------------+
391 //
392 // Here {K} represents the number for formal parameters of the active function,
393 // whereas {N} represents the actual number of arguments passed at runtime.
394 // Note that {N < K} can happen and causes {K} to be capped accordingly.
395 //
396 // Also note that it is possible for an arguments object of {kMappedArguments}
397 // type to carry a backing store of {kUnappedArguments} type when {K == 0}.
398 typedef CreateArgumentsType ArgumentsStateType;
399
400 ArgumentsStateType ArgumentsStateTypeOf(Operator const*) V8_WARN_UNUSED_RESULT;
401
402 uint32_t ObjectIdOf(Operator const*);
403
404 MachineRepresentation DeadValueRepresentationOf(Operator const*)
405 V8_WARN_UNUSED_RESULT;
406
407 class IfValueParameters final {
408 public:
IfValueParameters(int32_t value,int32_t comparison_order)409 IfValueParameters(int32_t value, int32_t comparison_order)
410 : value_(value), comparison_order_(comparison_order) {}
411
value()412 int32_t value() const { return value_; }
comparison_order()413 int32_t comparison_order() const { return comparison_order_; }
414
415 private:
416 int32_t value_;
417 int32_t comparison_order_;
418 };
419
420 V8_EXPORT_PRIVATE bool operator==(IfValueParameters const&,
421 IfValueParameters const&);
422
423 size_t hash_value(IfValueParameters const&);
424
425 V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream&,
426 IfValueParameters const&);
427
428 V8_EXPORT_PRIVATE IfValueParameters const& IfValueParametersOf(
429 const Operator* op) V8_WARN_UNUSED_RESULT;
430
431 const FrameStateInfo& FrameStateInfoOf(const Operator* op)
432 V8_WARN_UNUSED_RESULT;
433
434 Handle<HeapObject> HeapConstantOf(const Operator* op) V8_WARN_UNUSED_RESULT;
435
436 // Interface for building common operators that can be used at any level of IR,
437 // including JavaScript, mid-level, and low-level.
438 class V8_EXPORT_PRIVATE CommonOperatorBuilder final
NON_EXPORTED_BASE(ZoneObject)439 : public NON_EXPORTED_BASE(ZoneObject) {
440 public:
441 explicit CommonOperatorBuilder(Zone* zone);
442
443 const Operator* Dead();
444 const Operator* DeadValue(MachineRepresentation rep);
445 const Operator* Unreachable();
446 const Operator* End(size_t control_input_count);
447 const Operator* Branch(BranchHint = BranchHint::kNone,
448 IsSafetyCheck = IsSafetyCheck::kSafetyCheck);
449 const Operator* IfTrue();
450 const Operator* IfFalse();
451 const Operator* IfSuccess();
452 const Operator* IfException();
453 const Operator* Switch(size_t control_output_count);
454 const Operator* IfValue(int32_t value, int32_t order = 0);
455 const Operator* IfDefault();
456 const Operator* Throw();
457 const Operator* Deoptimize(DeoptimizeKind kind, DeoptimizeReason reason,
458 VectorSlotPair const& feedback);
459 const Operator* DeoptimizeIf(
460 DeoptimizeKind kind, DeoptimizeReason reason,
461 VectorSlotPair const& feedback,
462 IsSafetyCheck is_safety_check = IsSafetyCheck::kSafetyCheck);
463 const Operator* DeoptimizeUnless(
464 DeoptimizeKind kind, DeoptimizeReason reason,
465 VectorSlotPair const& feedback,
466 IsSafetyCheck is_safety_check = IsSafetyCheck::kSafetyCheck);
467 const Operator* TrapIf(TrapId trap_id);
468 const Operator* TrapUnless(TrapId trap_id);
469 const Operator* Return(int value_input_count = 1);
470 const Operator* Terminate();
471
472 const Operator* Start(int value_output_count);
473 const Operator* Loop(int control_input_count);
474 const Operator* Merge(int control_input_count);
475 const Operator* Parameter(int index, const char* debug_name = nullptr);
476
477 const Operator* OsrNormalEntry();
478 const Operator* OsrLoopEntry();
479 const Operator* OsrValue(int index);
480
481 const Operator* Int32Constant(int32_t);
482 const Operator* Int64Constant(int64_t);
483 const Operator* Float32Constant(volatile float);
484 const Operator* Float64Constant(volatile double);
485 const Operator* ExternalConstant(const ExternalReference&);
486 const Operator* NumberConstant(volatile double);
487 const Operator* PointerConstant(intptr_t);
488 const Operator* HeapConstant(const Handle<HeapObject>&);
489 const Operator* ObjectId(uint32_t);
490
491 const Operator* RelocatableInt32Constant(int32_t value,
492 RelocInfo::Mode rmode);
493 const Operator* RelocatableInt64Constant(int64_t value,
494 RelocInfo::Mode rmode);
495
496 const Operator* Select(MachineRepresentation, BranchHint = BranchHint::kNone);
497 const Operator* Phi(MachineRepresentation representation,
498 int value_input_count);
499 const Operator* EffectPhi(int effect_input_count);
500 const Operator* InductionVariablePhi(int value_input_count);
501 const Operator* LoopExit();
502 const Operator* LoopExitValue();
503 const Operator* LoopExitEffect();
504 const Operator* Checkpoint();
505 const Operator* BeginRegion(RegionObservability);
506 const Operator* FinishRegion();
507 const Operator* StateValues(int arguments, SparseInputMask bitmask);
508 const Operator* TypedStateValues(const ZoneVector<MachineType>* types,
509 SparseInputMask bitmask);
510 const Operator* ArgumentsElementsState(ArgumentsStateType type);
511 const Operator* ArgumentsLengthState(ArgumentsStateType type);
512 const Operator* ObjectState(uint32_t object_id, int pointer_slots);
513 const Operator* TypedObjectState(uint32_t object_id,
514 const ZoneVector<MachineType>* types);
515 const Operator* FrameState(BailoutId bailout_id,
516 OutputFrameStateCombine state_combine,
517 const FrameStateFunctionInfo* function_info);
518 const Operator* Call(const CallDescriptor* call_descriptor);
519 const Operator* CallWithCallerSavedRegisters(
520 const CallDescriptor* call_descriptor);
521 const Operator* TailCall(const CallDescriptor* call_descriptor);
522 const Operator* Projection(size_t index);
523 const Operator* Retain();
524 const Operator* TypeGuard(Type type);
525
526 // Constructs a new merge or phi operator with the same opcode as {op}, but
527 // with {size} inputs.
528 const Operator* ResizeMergeOrPhi(const Operator* op, int size);
529
530 // Constructs function info for frame state construction.
531 const FrameStateFunctionInfo* CreateFrameStateFunctionInfo(
532 FrameStateType type, int parameter_count, int local_count,
533 Handle<SharedFunctionInfo> shared_info);
534
535 const Operator* MarkAsSafetyCheck(const Operator* op,
536 IsSafetyCheck safety_check);
537
538 private:
539 Zone* zone() const { return zone_; }
540
541 const CommonOperatorGlobalCache& cache_;
542 Zone* const zone_;
543
544 DISALLOW_COPY_AND_ASSIGN(CommonOperatorBuilder);
545 };
546
547 } // namespace compiler
548 } // namespace internal
549 } // namespace v8
550
551 #endif // V8_COMPILER_COMMON_OPERATOR_H_
552