dart::Location Class Reference

#include <locations.h>

Inheritance diagram for dart::Location:

Public Types
enum	Kind : intptr_t {   kInvalid = 0 , kConstantTag = 1 , kPairLocationTag = 2 , kUnallocated = 1 << 2 ,   kStackSlot = 2 << 2 , kDoubleStackSlot = 3 << 2 , kQuadStackSlot = 4 << 2 , kRegister = 5 << 2 ,   kFpuRegister = 6 << 2 }
enum	Policy {   kAny , kPrefersRegister , kRequiresRegister , kRequiresFpuRegister ,   kWritableRegister , kSameAsFirstInput , kRequiresStack }

Public Member Functions
	Location ()
	Location (const Location &other)
Location &	operator= (const Location &other)
bool	IsInvalid () const
bool	IsConstant () const
intptr_t	pair_index () const
ConstantInstr *	constant_instruction () const
const Object &	constant () const
bool	IsPairLocation () const
PairLocation *	AsPairLocation () const
Location	Component (intptr_t i) const
bool	IsUnallocated () const
bool	IsRegisterBeneficial ()
Policy	policy () const
bool	IsRegister () const
Register	reg () const
bool	IsFpuRegister () const
FpuRegister	fpu_reg () const
bool	IsMachineRegister () const
intptr_t	register_code () const
bool	IsStackSlot () const
bool	IsDoubleStackSlot () const
bool	IsQuadStackSlot () const
Register	base_reg () const
intptr_t	stack_index () const
bool	HasStackIndex () const
intptr_t	ToStackSlotOffset () const
Location	ToSpRelative (intptr_t fp_to_sp_delta) const
Location	ToEntrySpRelative () const
Location	ToCallerSpRelative () const
const char *	Name () const
void	PrintTo (BaseTextBuffer *f) const
void	Print () const
const char *	ToCString () const
bool	Equals (Location other) const
Kind	kind () const
Location	Copy () const
void	Write (FlowGraphSerializer *s) const
Public Member Functions inherited from dart::ValueObject
	ValueObject ()
	~ValueObject ()

Static Public Member Functions
static Location	Constant (const ConstantInstr *obj, int pair_index=0)
static Location	Pair (Location first, Location second)
static Location	UnallocatedLocation (Policy policy)
static Location	Any ()
static Location	RequiresStack ()
static Location	PrefersRegister ()
static Location	RequiresRegister ()
static Location	RequiresFpuRegister ()
static Location	WritableRegister ()
static Location	SameAsFirstInput ()
static Location	NoLocation ()
static Location	RegisterLocation (Register reg)
static Location	FpuRegisterLocation (FpuRegister reg)
static bool	IsMachineRegisterKind (Kind kind)
static Location	MachineRegisterLocation (Kind kind, intptr_t reg)
static uword	EncodeStackIndex (intptr_t stack_index)
static Location	StackSlot (intptr_t stack_index, Register base)
static Location	DoubleStackSlot (intptr_t stack_index, Register base)
static Location	QuadStackSlot (intptr_t stack_index, Register base)
static Location	Read (FlowGraphDeserializer *d)

Detailed Description

Definition at line 198 of file locations.h.

Member Enumeration Documentation

Kind

enum dart::Location::Kind : intptr_t

Enumerator
kInvalid
kConstantTag
kPairLocationTag
kUnallocated
kStackSlot
kDoubleStackSlot
kQuadStackSlot
kRegister
kFpuRegister

Definition at line 219 of file locations.h.

            : intptr_t {
    // This location is invalid.  Payload must be zero.
    kInvalid = 0,
 
    // Constant value. This location contains a tagged Object handle.
    kConstantTag = 1,
 
    // This location contains a tagged pointer to a PairLocation.
    kPairLocationTag = 2,
 
    // Unallocated location represents a location that is not fixed and can be
    // allocated by a register allocator.  Each unallocated location has
    // a policy that specifies what kind of location is suitable. Payload
    // contains register allocation policy.
    kUnallocated = 1 << 2,
 
    // Spill slots allocated by the register allocator.  Payload contains
    // a spill index.
    kStackSlot = 2 << 2,        // Word size slot.
    kDoubleStackSlot = 3 << 2,  // 64bit stack slot.
    kQuadStackSlot = 4 << 2,    // 128bit stack slot.
 
    // Register location represents a fixed register.  Payload contains
    // register code.
    kRegister = 5 << 2,
 
    // FpuRegister location represents a fixed fpu register.  Payload contains
    // its code.
    kFpuRegister = 6 << 2,
  };

Policy

enum dart::Location::Policy

Enumerator
kAny
kPrefersRegister
kRequiresRegister
kRequiresFpuRegister
kWritableRegister
kSameAsFirstInput
kRequiresStack

Definition at line 328 of file locations.h.

              {
    kAny,
    kPrefersRegister,
    kRequiresRegister,
    kRequiresFpuRegister,
    kWritableRegister,
    kSameAsFirstInput,
    // Forces the location to be spilled to the stack.
    // Currently only used for `Handle` arguments in `FfiCall` instructions.
    // Only available in optimized mode.
    kRequiresStack,
  };

Constructor & Destructor Documentation

Location() [1/2]

dart::Location::Location ( )

inline

Definition at line 250 of file locations.h.

             : value_(kInvalidLocation) {
    // Verify that non-tagged location kinds do not interfere with location tags
    // (kConstantTag and kPairLocationTag).
    COMPILE_ASSERT((kInvalid & kLocationTagMask) != kConstantTag);
    COMPILE_ASSERT((kInvalid & kLocationTagMask) != kPairLocationTag);
 
    COMPILE_ASSERT((kUnallocated & kLocationTagMask) != kConstantTag);
    COMPILE_ASSERT((kUnallocated & kLocationTagMask) != kPairLocationTag);
 
    COMPILE_ASSERT((kStackSlot & kLocationTagMask) != kConstantTag);
    COMPILE_ASSERT((kStackSlot & kLocationTagMask) != kPairLocationTag);
 
    COMPILE_ASSERT((kDoubleStackSlot & kLocationTagMask) != kConstantTag);
    COMPILE_ASSERT((kDoubleStackSlot & kLocationTagMask) != kPairLocationTag);
 
    COMPILE_ASSERT((kQuadStackSlot & kLocationTagMask) != kConstantTag);
    COMPILE_ASSERT((kQuadStackSlot & kLocationTagMask) != kPairLocationTag);
 
    COMPILE_ASSERT((kRegister & kLocationTagMask) != kConstantTag);
    COMPILE_ASSERT((kRegister & kLocationTagMask) != kPairLocationTag);
 
    COMPILE_ASSERT((kFpuRegister & kLocationTagMask) != kConstantTag);
    COMPILE_ASSERT((kFpuRegister & kLocationTagMask) != kPairLocationTag);
 
    // Verify tags and tagmask.
    COMPILE_ASSERT((kConstantTag & kLocationTagMask) == kConstantTag);
 
    COMPILE_ASSERT((kPairLocationTag & kLocationTagMask) == kPairLocationTag);
 
    ASSERT(IsInvalid());
  }

Location() [2/2]

dart::Location::Location ( const Location &  other )

inline

Definition at line 282 of file locations.h.

: ValueObject(), value_(other.value_) {}

Member Function Documentation

Any()

static Location dart::Location::Any ( )

inlinestatic

Definition at line 352 of file locations.h.

{ return UnallocatedLocation(kAny); }

AsPairLocation()

PairLocation * Location::AsPairLocation

(

)

const

Definition at line 280 of file locations.cc.

                                             {
  ASSERT(IsPairLocation());
  return reinterpret_cast<PairLocation*>(value_ & ~kLocationTagMask);
}

base_reg()

Register dart::Location::base_reg ( ) const

inline

Definition at line 480 of file locations.h.

                            {
    ASSERT(HasStackIndex());
    return StackSlotBaseField::decode(payload());
  }

Component()

Location Location::Component

(

intptr_t

i

)

const

Definition at line 285 of file locations.cc.

                                             {
  return AsPairLocation()->At(i);
}

constant()

const Object & Location::constant

(

)

const

Definition at line 373 of file locations.cc.

                                       {
  return constant_instruction()->value();
}

Constant()

static Location dart::Location::Constant ( const ConstantInstr *  obj, int  pair_index = 0  )

inlinestatic

Definition at line 294 of file locations.h.

                                                                         {
    ASSERT((pair_index == 0) || (pair_index == 1));
    Location loc(reinterpret_cast<uword>(obj) |
                 (pair_index != 0 ? static_cast<uword>(kPairLocationTag) : 0) |
                 static_cast<uword>(kConstantTag));
    ASSERT(obj == loc.constant_instruction());
    ASSERT(loc.pair_index() == pair_index);
    return loc;
  }

constant_instruction()

ConstantInstr * dart::Location::constant_instruction ( ) const

inline

Definition at line 309 of file locations.h.

                                              {
    ASSERT(IsConstant());
    return reinterpret_cast<ConstantInstr*>(value_ & ~kLocationTagMask);
  }

Copy()

Location Location::Copy

(

)

const

Definition at line 468 of file locations.cc.

                              {
  if (IsPairLocation()) {
    PairLocation* pair = AsPairLocation();
    ASSERT(!pair->At(0).IsPairLocation());
    ASSERT(!pair->At(1).IsPairLocation());
    return Location::Pair(pair->At(0).Copy(), pair->At(1).Copy());
  } else {
    // Copy by value.
    return *this;
  }
}

DoubleStackSlot()

static Location dart::Location::DoubleStackSlot ( intptr_t  stack_index, Register  base  )

inlinestatic

Definition at line 458 of file locations.h.

                                                                       {
    uword payload = StackSlotBaseField::encode(base) |
                    StackIndexField::encode(EncodeStackIndex(stack_index));
    Location loc(kDoubleStackSlot, payload);
    // Ensure that sign is preserved.
    ASSERT(loc.stack_index() == stack_index);
    return loc;
  }

EncodeStackIndex()

static uword dart::Location::EncodeStackIndex ( intptr_t  stack_index )

inlinestatic

Definition at line 441 of file locations.h.

                                                      {
    ASSERT((-kStackIndexBias <= stack_index) &&
           (stack_index < kStackIndexBias));
    return static_cast<uword>(kStackIndexBias + stack_index);
  }

Equals()

bool dart::Location::Equals ( Location  other ) const

inline

Definition at line 519 of file locations.h.

{ return value_ == other.value_; }

fpu_reg()

FpuRegister dart::Location::fpu_reg ( ) const

inline

Definition at line 416 of file locations.h.

                              {
    ASSERT(IsFpuRegister());
    return static_cast<FpuRegister>(payload());
  }

FpuRegisterLocation()

static Location dart::Location::FpuRegisterLocation ( FpuRegister  reg )

inlinestatic

Definition at line 410 of file locations.h.

                                                       {
    return Location(kFpuRegister, reg);
  }

HasStackIndex()

bool dart::Location::HasStackIndex ( ) const

inline

Definition at line 491 of file locations.h.

                             {
    return IsStackSlot() || IsDoubleStackSlot() || IsQuadStackSlot();
  }

IsConstant()

bool dart::Location::IsConstant ( ) const

inline

Definition at line 292 of file locations.h.

{ return (value_ & kConstantTag) == kConstantTag; }

IsDoubleStackSlot()

bool dart::Location::IsDoubleStackSlot ( ) const

inline

Definition at line 467 of file locations.h.

{ return kind() == kDoubleStackSlot; }

IsFpuRegister()

bool dart::Location::IsFpuRegister ( ) const

inline

Definition at line 414 of file locations.h.

{ return kind() == kFpuRegister; }

IsInvalid()

bool dart::Location::IsInvalid ( ) const

inline

Definition at line 289 of file locations.h.

{ return value_ == kInvalidLocation; }

IsMachineRegister()

bool dart::Location::IsMachineRegister ( ) const

inline

Definition at line 434 of file locations.h.

{ return IsMachineRegisterKind(kind()); }

IsMachineRegisterKind()

static bool dart::Location::IsMachineRegisterKind ( Kind  kind )

inlinestatic

Definition at line 421 of file locations.h.

                                               {
    return (kind == kRegister) || (kind == kFpuRegister);
  }

IsPairLocation()

bool dart::Location::IsPairLocation ( ) const

inline

Definition at line 316 of file locations.h.

                              {
    return (value_ & kLocationTagMask) == kPairLocationTag;
  }

IsQuadStackSlot()

bool dart::Location::IsQuadStackSlot ( ) const

inline

Definition at line 478 of file locations.h.

{ return kind() == kQuadStackSlot; }

IsRegister()

bool dart::Location::IsRegister ( ) const

inline

Definition at line 402 of file locations.h.

{ return kind() == kRegister; }

IsRegisterBeneficial()

bool dart::Location::IsRegisterBeneficial ( )

inline

Definition at line 343 of file locations.h.

                              {
    return !Equals(Any()) && !Equals(RequiresStack());
  }

IsStackSlot()

bool dart::Location::IsStackSlot ( ) const

inline

Definition at line 456 of file locations.h.

{ return kind() == kStackSlot; }

IsUnallocated()

bool dart::Location::IsUnallocated ( ) const

inline

Definition at line 341 of file locations.h.

{ return kind() == kUnallocated; }

kind()

Kind dart::Location::kind ( ) const

inline

Definition at line 523 of file locations.h.

{ return KindField::decode(value_); }

MachineRegisterLocation()

static Location dart::Location::MachineRegisterLocation ( Kind  kind, intptr_t  reg  )

inlinestatic

Definition at line 425 of file locations.h.

                                                                   {
    if (kind == kRegister) {
      return RegisterLocation(static_cast<Register>(reg));
    } else {
      ASSERT(kind == kFpuRegister);
      return FpuRegisterLocation(static_cast<FpuRegister>(reg));
    }
  }

Name()

const char * Location::Name

(

)

const

Definition at line 377 of file locations.cc.

                                 {
  switch (kind()) {
    case kInvalid:
      return "?";
    case kRegister:
      return RegisterNames::RegisterName(reg());
    case kFpuRegister:
      return RegisterNames::FpuRegisterName(fpu_reg());
    case kStackSlot:
      return "S";
    case kDoubleStackSlot:
      return "DS";
    case kQuadStackSlot:
      return "QS";
    case kUnallocated:
      switch (policy()) {
        case kAny:
          return "A";
        case kPrefersRegister:
          return "P";
        case kRequiresRegister:
          return "R";
        case kRequiresFpuRegister:
          return "DR";
        case kWritableRegister:
          return "WR";
        case kSameAsFirstInput:
          return "0";
        case kRequiresStack:
          return "RS";
      }
      UNREACHABLE();
    default:
      if (IsConstant()) {
        return "C";
      } else {
        ASSERT(IsPairLocation());
        return "2P";
      }
  }
  return "?";
}

NoLocation()

static Location dart::Location::NoLocation ( )

inlinestatic

Definition at line 387 of file locations.h.

{ return Location(); }

operator=()

Location & dart::Location::operator= ( const Location &  other )

inline

Definition at line 284 of file locations.h.

                                             {
    value_ = other.value_;
    return *this;
  }

Pair()

Location Location::Pair ( Location  first, Location  second  )

static

Definition at line 271 of file locations.cc.

                                                       {
  PairLocation* pair_location = new PairLocation();
  ASSERT((reinterpret_cast<intptr_t>(pair_location) & kLocationTagMask) == 0);
  pair_location->SetAt(0, first);
  pair_location->SetAt(1, second);
  Location loc(reinterpret_cast<uword>(pair_location) | kPairLocationTag);
  return loc;
}

pair_index()

intptr_t dart::Location::pair_index ( ) const

inline

Definition at line 304 of file locations.h.

                              {
    ASSERT(IsConstant());
    return (value_ & kPairLocationTag) != 0 ? 1 : 0;
  }

policy()

Policy dart::Location::policy ( ) const

inline

Definition at line 389 of file locations.h.

                        {
    ASSERT(IsUnallocated());
    return PolicyField::decode(payload());
  }

PrefersRegister()

static Location dart::Location::PrefersRegister ( )

inlinestatic

Definition at line 358 of file locations.h.

                                    {
    return UnallocatedLocation(kPrefersRegister);
  }

Print()

void Location::Print

(

)

const

Definition at line 452 of file locations.cc.

                           {
  if (kind() == kStackSlot || kind() == kDoubleStackSlot ||
      kind() == kQuadStackSlot) {
    const char* suffix = "";
    if (kind() == kDoubleStackSlot) {
      suffix = " f64";
    } else if (kind() == kQuadStackSlot) {
      suffix = " f128";
    }
    THR_Print("%s[%" Pd "] %s", base_reg() == FPREG ? "fp" : "sp",
              stack_index(), suffix);
  } else {
    THR_Print("%s", Name());
  }
}

PrintTo()

void Location::PrintTo

(

BaseTextBuffer *

f

)

const

Definition at line 420 of file locations.cc.

                                              {
  if (!FLAG_support_il_printer) {
    return;
  }
  if (kind() == kStackSlot || kind() == kDoubleStackSlot ||
      kind() == kQuadStackSlot) {
    const char* suffix = "";
    if (kind() == kDoubleStackSlot) {
      suffix = " f64";
    } else if (kind() == kQuadStackSlot) {
      suffix = " f128";
    }
    f->Printf("%s[%" Pd "]%s", base_reg() == FPREG ? "fp" : "sp", stack_index(),
              suffix);
  } else if (IsPairLocation()) {
    f->AddString("(");
    AsPairLocation()->At(0).PrintTo(f);
    f->AddString(", ");
    AsPairLocation()->At(1).PrintTo(f);
    f->AddString(")");
  } else {
    f->Printf("%s", Name());
  }
}

QuadStackSlot()

static Location dart::Location::QuadStackSlot ( intptr_t  stack_index, Register  base  )

inlinestatic

Definition at line 469 of file locations.h.

                                                                     {
    uword payload = StackSlotBaseField::encode(base) |
                    StackIndexField::encode(EncodeStackIndex(stack_index));
    Location loc(kQuadStackSlot, payload);
    // Ensure that sign is preserved.
    ASSERT(loc.stack_index() == stack_index);
    return loc;
  }

Read()

Location Location::Read ( FlowGraphDeserializer *  d )

static

Definition at line 1243 of file il_serializer.cc.

                                                {
  const uword value = d->Read<uword>();
  if (value == kPairLocationTag) {
    const Location first = Location::Read(d);
    const Location second = Location::Read(d);
    return Location::Pair(first, second);
  } else if ((value & kConstantTag) == kConstantTag) {
    ConstantInstr* instr = d->ReadRef<Definition*>()->AsConstant();
    ASSERT(instr != nullptr);
    const int pair_index = (value & kPairLocationTag) != 0 ? 1 : 0;
    return Location::Constant(instr, pair_index);
  } else {
    return Location(value);
  }
}

reg()

Register dart::Location::reg ( ) const

inline

Definition at line 404 of file locations.h.

                       {
    ASSERT(IsRegister());
    return static_cast<Register>(payload());
  }

register_code()

intptr_t dart::Location::register_code ( ) const

inline

Definition at line 436 of file locations.h.

                                 {
    ASSERT(IsMachineRegister());
    return static_cast<intptr_t>(payload());
  }

RegisterLocation()

static Location dart::Location::RegisterLocation ( Register  reg )

inlinestatic

Definition at line 398 of file locations.h.

                                                 {
    return Location(kRegister, reg);
  }

RequiresFpuRegister()

static Location dart::Location::RequiresFpuRegister ( )

inlinestatic

Definition at line 369 of file locations.h.

                                        {
    return UnallocatedLocation(kRequiresFpuRegister);
  }

RequiresRegister()

static Location dart::Location::RequiresRegister ( )

inlinestatic

Definition at line 365 of file locations.h.

                                     {
    return UnallocatedLocation(kRequiresRegister);
  }

RequiresStack()

static Location dart::Location::RequiresStack ( )

inlinestatic

Definition at line 354 of file locations.h.

                                  {
    return UnallocatedLocation(kRequiresStack);
  }

SameAsFirstInput()

static Location dart::Location::SameAsFirstInput ( )

inlinestatic

Definition at line 382 of file locations.h.

                                     {
    return UnallocatedLocation(kSameAsFirstInput);
  }

stack_index()

intptr_t dart::Location::stack_index ( ) const

inline

Definition at line 485 of file locations.h.

                               {
    ASSERT(HasStackIndex());
    // Decode stack index manually to preserve sign.
    return StackIndexField::decode(payload()) - kStackIndexBias;
  }

StackSlot()

static Location dart::Location::StackSlot ( intptr_t  stack_index, Register  base  )

inlinestatic

Definition at line 447 of file locations.h.

                                                                 {
    uword payload = StackSlotBaseField::encode(base) |
                    StackIndexField::encode(EncodeStackIndex(stack_index));
    Location loc(kStackSlot, payload);
    // Ensure that sign is preserved.
    ASSERT(loc.stack_index() == stack_index);
    return loc;
  }

ToCallerSpRelative()

Location Location::ToCallerSpRelative

(

)

const

Definition at line 265 of file locations.cc.

                                            {
  const auto fp_to_caller_sp_delta =
      (compiler::target::frame_layout.param_end_from_fp + 1);
  return ToSpRelative(fp_to_caller_sp_delta);
}

ToCString()

const char * Location::ToCString

(

)

const

Definition at line 445 of file locations.cc.

                                      {
  char buffer[1024];
  BufferFormatter bf(buffer, 1024);
  PrintTo(&bf);
  return Thread::Current()->zone()->MakeCopyOfString(buffer);
}

ToEntrySpRelative()

Location Location::ToEntrySpRelative

(

)

const

Definition at line 258 of file locations.cc.

                                           {
  const auto fp_to_entry_sp_delta =
      (compiler::target::frame_layout.param_end_from_fp + 1) -
      compiler::target::frame_layout.last_param_from_entry_sp;
  return ToSpRelative(fp_to_entry_sp_delta);
}

ToSpRelative()

Location Location::ToSpRelative

(

intptr_t

fp_to_sp_delta

)

const

Definition at line 240 of file locations.cc.

                                                             {
  if (IsPairLocation()) {
    auto pair = AsPairLocation();
    return Pair(pair->At(0).ToSpRelative(fp_to_sp_delta),
                pair->At(1).ToSpRelative(fp_to_sp_delta));
  }
 
  if (HasStackIndex()) {
    ASSERT(base_reg() == FPREG);
    uword payload = StackSlotBaseField::encode(SPREG) |
                    StackIndexField::encode(
                        EncodeStackIndex(stack_index() - fp_to_sp_delta));
    return Location(kind(), payload);
  }
 
  return *this;
}

ToStackSlotOffset()

intptr_t Location::ToStackSlotOffset

(

)

const

Definition at line 369 of file locations.cc.

                                           {
  return stack_index() * compiler::target::kWordSize;
}

UnallocatedLocation()

static Location dart::Location::UnallocatedLocation ( Policy  policy )

inlinestatic

Definition at line 347 of file locations.h.

                                                     {
    return Location(kUnallocated, PolicyField::encode(policy));
  }

WritableRegister()

static Location dart::Location::WritableRegister ( )

inlinestatic

Definition at line 376 of file locations.h.

                                     {
    return UnallocatedLocation(kWritableRegister);
  }

Write()

void Location::Write

(

FlowGraphSerializer *

s

)

const

Definition at line 1229 of file il_serializer.cc.

                                                 {
  if (IsPairLocation()) {
    s->Write<uword>(value_ & kLocationTagMask);
    PairLocation* pair = AsPairLocation();
    pair->At(0).Write(s);
    pair->At(1).Write(s);
  } else if (IsConstant()) {
    s->Write<uword>(value_ & kLocationTagMask);
    s->WriteRef<Definition*>(constant_instruction());
  } else {
    s->Write<uword>(value_);
  }
}

---

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

• third_party/dart-lang/sdk/runtime/vm/compiler/backend/locations.h
• third_party/dart-lang/sdk/runtime/vm/compiler/backend/il_serializer.cc
• third_party/dart-lang/sdk/runtime/vm/compiler/backend/locations.cc