dart::kernel::ConstantReader Class Reference

#include <constant_reader.h>

Public Member Functions
	ConstantReader (KernelReaderHelper *helper, ActiveClass *active_class)
virtual	~ConstantReader ()
bool	IsPragmaInstanceConstant (intptr_t constant_index, intptr_t *pragma_name_constant_index, intptr_t *pragma_options_constant_index)
bool	IsStringConstant (intptr_t constant_index, const char *name)
bool	GetStringConstant (intptr_t constant_index, String *out_value)
InstancePtr	ReadConstantInitializer ()
InstancePtr	ReadConstantExpression ()
ObjectPtr	ReadAnnotations ()
bool	IsInstanceConstant (intptr_t constant_index, const Class &clazz)
InstancePtr	ReadConstant (intptr_t constant_index)
intptr_t	NumConstants ()

Detailed Description

Definition at line 20 of file constant_reader.h.

Constructor & Destructor Documentation

ConstantReader()

dart::kernel::ConstantReader::ConstantReader	(	KernelReaderHelper *	helper,
		ActiveClass *	active_class
	)

Definition at line 19 of file constant_reader.cc.

    : helper_(helper),
      zone_(helper->zone_),
      translation_helper_(helper->translation_helper_),
      active_class_(active_class),
      result_(Object::Handle(zone_)) {}

~ConstantReader()

virtual dart::kernel::ConstantReader::~ConstantReader ( )

inlinevirtual

Definition at line 24 of file constant_reader.h.

{}

Member Function Documentation

GetStringConstant()

bool dart::kernel::ConstantReader::GetStringConstant	(	intptr_t	constant_index,
		String *	out_value
	)

Definition at line 87 of file constant_reader.cc.

                                                          {
  KernelReaderHelper reader(Z, &H, H.constants_table(), 0);
  NavigateToIndex(&reader, constant_index);
 
  if (reader.ReadByte() == kStringConstant) {
    const StringIndex index = reader.ReadStringReference();
    *out_value = H.DartSymbolPlain(index).ptr();
    return true;
  }
  return false;
}

IsInstanceConstant()

bool dart::kernel::ConstantReader::IsInstanceConstant	(	intptr_t	constant_index,
		const Class &	clazz
	)

Definition at line 193 of file constant_reader.cc.

                                                            {
  // Get reader directly into raw bytes of constant table/constant mapping.
  KernelReaderHelper reader(Z, &H, H.constants_table(), 0);
  NavigateToIndex(&reader, constant_index);
 
  // Peek for an instance of the given clazz.
  if (reader.ReadByte() == kInstanceConstant) {
    const NameIndex index = reader.ReadCanonicalNameReference();
    return H.LookupClassByKernelClass(index) == clazz.ptr();
  }
  return false;
}

IsPragmaInstanceConstant()

bool dart::kernel::ConstantReader::IsPragmaInstanceConstant	(	intptr_t	constant_index,
		intptr_t *	pragma_name_constant_index,
		intptr_t *	pragma_options_constant_index
	)

Definition at line 27 of file constant_reader.cc.

                                             {
  KernelReaderHelper reader(Z, &H, H.constants_table(), 0);
  NavigateToIndex(&reader, constant_index);
 
  if (reader.ReadByte() == kInstanceConstant) {
    NameIndex index = reader.ReadCanonicalNameReference();
    if (H.IsRoot(index) ||
        !H.StringEquals(H.CanonicalNameString(index), "pragma")) {
      return false;
    }
    index = H.CanonicalNameParent(index);
    if (H.IsRoot(index) ||
        !H.StringEquals(H.CanonicalNameString(index), "dart:core")) {
      return false;
    }
    const intptr_t num_type_args = reader.ReadUInt();
    if (num_type_args != 0) return false;
 
    const intptr_t num_fields = reader.ReadUInt();
    if (num_fields != 2) return false;
 
    const NameIndex field0_name = reader.ReadCanonicalNameReference();
    if (H.IsRoot(field0_name) ||
        !H.StringEquals(H.CanonicalNameString(field0_name), "name")) {
      return false;
    }
    const intptr_t name_index = reader.ReadUInt();
    if (pragma_name_constant_index != nullptr) {
      *pragma_name_constant_index = name_index;
    }
 
    const NameIndex field1_name = reader.ReadCanonicalNameReference();
    if (H.IsRoot(field1_name) ||
        !H.StringEquals(H.CanonicalNameString(field1_name), "options")) {
      return false;
    }
    const intptr_t options_index = reader.ReadUInt();
    if (pragma_options_constant_index != nullptr) {
      *pragma_options_constant_index = options_index;
    }
    return true;
  }
  return false;
}

IsStringConstant()

bool dart::kernel::ConstantReader::IsStringConstant	(	intptr_t	constant_index,
		const char *	name
	)

Definition at line 75 of file constant_reader.cc.

                                                        {
  KernelReaderHelper reader(Z, &H, H.constants_table(), 0);
  NavigateToIndex(&reader, constant_index);
 
  if (reader.ReadByte() == kStringConstant) {
    const StringIndex index = reader.ReadStringReference();
    return H.StringEquals(index, name);
  }
  return false;
}

NumConstants()

intptr_t dart::kernel::ConstantReader::NumConstants

(

)

Definition at line 207 of file constant_reader.cc.

                                      {
  ASSERT(!H.constants_table().IsNull());
  KernelReaderHelper reader(Z, &H, H.constants_table(), 0);
  return NumConstants(&reader);
}

ReadAnnotations()

ObjectPtr dart::kernel::ConstantReader::ReadAnnotations

(

)

Definition at line 147 of file constant_reader.cc.

                                          {
  intptr_t list_length = helper_->ReadListLength();  // read list length.
  const auto& metadata_values =
      Array::Handle(Z, ImmutableArray::New(list_length, H.allocation_space()));
  Instance& value = Instance::Handle(Z);
  for (intptr_t i = 0; i < list_length; ++i) {
    // This will read the expression.
    value = ReadConstantExpression();
    metadata_values.SetAt(i, value);
  }
  return H.Canonicalize(metadata_values);
}

ReadConstant()

InstancePtr dart::kernel::ConstantReader::ReadConstant

(

intptr_t

constant_index

)

Definition at line 160 of file constant_reader.cc.

                                                                {
  ASSERT(!H.constants().IsNull());
  ASSERT(!H.constants_table().IsNull());  // raw bytes
 
  // For kernel-level cache (in contrast with script-level caching),
  // we need to access the raw constants array inside the shared
  // KernelProgramInfo directly, so that all scripts will see the
  // results after new insertions. These accesses at kernel-level
  // must be locked since mutator and background compiler can
  // access the array at the same time.
  {
    SafepointMutexLocker ml(
        H.thread()->isolate_group()->kernel_constants_mutex());
    const auto& constants_array =
        Array::Handle(Z, H.GetKernelProgramInfo().constants());
    ASSERT(constant_index < constants_array.Length());
    result_ = constants_array.At(constant_index);
  }
 
  // On miss, evaluate, and insert value.
  if (result_.ptr() == Object::sentinel().ptr()) {
    LeaveCompilerScope cs(H.thread());
    result_ = ReadConstantInternal(constant_index);
    SafepointMutexLocker ml(
        H.thread()->isolate_group()->kernel_constants_mutex());
    const auto& constants_array =
        Array::Handle(Z, H.GetKernelProgramInfo().constants());
    ASSERT(constant_index < constants_array.Length());
    constants_array.SetAt(constant_index, result_);
  }
  return Instance::RawCast(result_.ptr());
}

ReadConstantExpression()

InstancePtr dart::kernel::ConstantReader::ReadConstantExpression

(

)

Definition at line 114 of file constant_reader.cc.

                                                   {
  Tag tag = helper_->ReadTag();  // read tag.
  switch (tag) {
    case kConstantExpression:
      helper_->ReadPosition();
      helper_->SkipDartType();
      result_ = ReadConstant(helper_->ReadUInt());
      break;
    case kFileUriConstantExpression:
      helper_->ReadPosition();
      helper_->ReadUInt();
      helper_->SkipDartType();
      result_ = ReadConstant(helper_->ReadUInt());
      break;
    case kInvalidExpression: {
      helper_->ReadPosition();  // Skip position.
      const String& message = H.DartString(helper_->ReadStringReference());
      const auto& script = Script::Handle(Z, Script());
      // Invalid expression message has pointer to the source code, no need to
      // report it twice.
      H.ReportError(script, TokenPosition::kNoSource, "%s",
                    message.ToCString());
      break;
    }
    default:
      const auto& script = Script::Handle(Z, Script());
      H.ReportError(script, TokenPosition::kNoSource,
                    "Not a constant expression: unexpected kernel tag %s (%d)",
                    Reader::TagName(tag), tag);
  }
  return Instance::RawCast(result_.ptr());
}

ReadConstantInitializer()

InstancePtr dart::kernel::ConstantReader::ReadConstantInitializer

(

)

Definition at line 100 of file constant_reader.cc.

                                                    {
  Tag tag = helper_->ReadTag();  // read tag.
  switch (tag) {
    case kSomething:
      return ReadConstantExpression();
    default:
      const auto& script = Script::Handle(Z, Script());
      H.ReportError(script, TokenPosition::kNoSource,
                    "Not a constant expression: unexpected kernel tag %s (%d)",
                    Reader::TagName(tag), tag);
  }
  return Instance::RawCast(result_.ptr());
}

---

The documentation for this class was generated from the following files:

• third_party/dart-lang/sdk/runtime/vm/compiler/frontend/constant_reader.h
• third_party/dart-lang/sdk/runtime/vm/compiler/frontend/constant_reader.cc