scope-info-inl.h

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// Copyright 2020 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
 
#ifndef V8_OBJECTS_SCOPE_INFO_INL_H_
#define V8_OBJECTS_SCOPE_INFO_INL_H_
 
#include "src/objects/scope-info.h"
// Include the non-inl header before the rest of the headers.
 
#include "src/heap/heap-write-barrier-inl.h"
#include "src/objects/fixed-array-inl.h"
#include "src/objects/string.h"
#include "src/roots/roots-inl.h"
#include "src/torque/runtime-macro-shims.h"
#include "src/torque/runtime-support.h"
 
// Has to be the last include (doesn't have include guards):
#include "src/objects/object-macros.h"
 
namespace v8 {
namespace internal {
 
#include "torque-generated/src/objects/scope-info-tq-inl.inc"
 
TQ_OBJECT_CONSTRUCTORS_IMPL(ScopeInfo)
 
bool ScopeInfo::IsAsmModule() const { return IsAsmModuleBit::decode(Flags()); }
 
bool ScopeInfo::HasSimpleParameters() const {
  return HasSimpleParametersBit::decode(Flags());
}
 
uint32_t ScopeInfo::Flags() const { return flags(kRelaxedLoad); }
int ScopeInfo::ParameterCount() const { return parameter_count(); }
int ScopeInfo::ContextLocalCount() const { return context_local_count(); }
 
Tagged<DependentCode> ScopeInfo::dependent_code() const {
  return Cast<DependentCode>(TorqueGeneratedScopeInfo::dependent_code());
}
 
ObjectSlot ScopeInfo::data_start() { return RawField(OffsetOfElementAt(0)); }
 
bool ScopeInfo::HasInlinedLocalNames() const {
  return ContextLocalCount() < kScopeInfoMaxInlinedLocalNamesSize;
}
 
template <typename ScopeInfoPtr>
class ScopeInfo::LocalNamesRange {
 public:
  class Iterator {
   public:
    Iterator(const LocalNamesRange* range, InternalIndex index)
        : range_(range), index_(index) {
      DCHECK_NOT_NULL(range);
      if (!range_->inlined()) advance_hashtable_index();
    }
 
    Iterator& operator++() {
      DCHECK_LT(index_, range_->max_index());
      ++index_;
      if (range_->inlined()) return *this;
      advance_hashtable_index();
      return *this;
    }
 
    friend bool operator==(const Iterator& a, const Iterator& b) {
      return a.range_ == b.range_ && a.index_ == b.index_;
    }
 
    friend bool operator!=(const Iterator& a, const Iterator& b) {
      return !(a == b);
    }
 
    Tagged<String> name(PtrComprCageBase cage_base) const {
      DCHECK_LT(index_, range_->max_index());
      if (range_->inlined()) {
        return scope_info()->ContextInlinedLocalName(cage_base,
                                                     index_.as_int());
      }
      return Cast<String>(table()->KeyAt(cage_base, index_));
    }
 
    Tagged<String> name() const {
      PtrComprCageBase cage_base = GetPtrComprCageBase(*scope_info());
      return name(cage_base);
    }
 
    const Iterator* operator*() const { return this; }
 
    int index() const {
      if (range_->inlined()) return index_.as_int();
      return table()->IndexAt(index_);
    }
 
   private:
    const LocalNamesRange* range_;
    InternalIndex index_;
 
    ScopeInfoPtr scope_info() const { return range_->scope_info_; }
 
    Tagged<NameToIndexHashTable> table() const {
      return scope_info()->context_local_names_hashtable();
    }
 
    void advance_hashtable_index() {
      DisallowGarbageCollection no_gc;
      ReadOnlyRoots roots = GetReadOnlyRoots();
      InternalIndex max = range_->max_index();
      // Increment until iterator points to a valid key or max.
      while (index_ < max) {
        Tagged<Object> key = table()->KeyAt(index_);
        if (table()->IsKey(roots, key)) break;
        ++index_;
      }
    }
 
    friend class LocalNamesRange;
  };
 
  bool inlined() const { return scope_info_->HasInlinedLocalNames(); }
 
  InternalIndex max_index() const {
    int max = inlined()
                  ? scope_info_->ContextLocalCount()
                  : scope_info_->context_local_names_hashtable()->Capacity();
    return InternalIndex(max);
  }
 
  explicit LocalNamesRange(ScopeInfoPtr scope_info) : scope_info_(scope_info) {}
 
  inline Iterator begin() const { return Iterator(this, InternalIndex(0)); }
 
  inline Iterator end() const { return Iterator(this, max_index()); }
 
 private:
  ScopeInfoPtr scope_info_;
};
 
// static
ScopeInfo::LocalNamesRange<DirectHandle<ScopeInfo>>
ScopeInfo::IterateLocalNames(DirectHandle<ScopeInfo> scope_info) {
  return LocalNamesRange<DirectHandle<ScopeInfo>>(scope_info);
}
 
// static
ScopeInfo::LocalNamesRange<Tagged<ScopeInfo>> ScopeInfo::IterateLocalNames(
    Tagged<ScopeInfo> scope_info, const DisallowGarbageCollection& no_gc) {
  USE(no_gc);
  return LocalNamesRange<Tagged<ScopeInfo>>(scope_info);
}
 
}  // namespace internal
}  // namespace v8
 
#include "src/objects/object-macros-undef.h"
 
#endif  // V8_OBJECTS_SCOPE_INFO_INL_H_