chromium/v8/src/compiler/globals.h

// Copyright 2019 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_COMPILER_GLOBALS_H_
#define V8_COMPILER_GLOBALS_H_

#include <ostream>

#include "src/common/globals.h"
#include "src/flags/flags.h"
#include "src/objects/js-objects.h"
#include "src/runtime/runtime.h"

namespace v8 {
namespace internal {
namespace compiler {

// The nci flag is currently used to experiment with feedback collection in
// optimized code produced by generic lowering.
// Considerations:
// - Should we increment the call count? https://crbug.com/v8/10524
// - Is feedback already megamorphic in all these cases?
//
// TODO(jgruber): Remove once we've made a decision whether to collect feedback
// unconditionally.
inline bool CollectFeedbackInGenericLowering() { … }

enum class StackCheckKind : uint8_t { … };

inline Runtime::FunctionId GetBuiltinForStackCheckKind(StackCheckKind kind) { … }

enum class CanThrow : uint8_t { … };
enum class LazyDeoptOnThrow : uint8_t { … };

inline std::ostream& operator<<(std::ostream& os,
                                LazyDeoptOnThrow lazy_deopt_on_throw) { … }

inline std::ostream& operator<<(std::ostream& os, StackCheckKind kind) { … }

inline size_t hash_value(StackCheckKind kind) { … }

enum class CheckForMinusZeroMode : uint8_t { … };

inline size_t hash_value(CheckForMinusZeroMode mode) { … }

inline std::ostream& operator<<(std::ostream& os, CheckForMinusZeroMode mode) { … }

// The CallFeedbackRelation provides the meaning of the call feedback for a
// TurboFan JSCall operator
// - kReceiver: The call target was Function.prototype.apply and its receiver
//   was recorded as the feedback value.
// - kTarget: The call target was recorded as the feedback value.
// - kUnrelated: The feedback is no longer related to the call. If, during
//   lowering, a JSCall (e.g. of a higher order function) is replaced by a
//   JSCall with another target, the feedback has to be kept but is now
//   unrelated.
enum class CallFeedbackRelation { … };

inline std::ostream& operator<<(std::ostream& os,
                                CallFeedbackRelation call_feedback_relation) { … }

// Maximum depth and total number of elements and properties for literal
// graphs to be considered for fast deep-copying. The limit is chosen to
// match the maximum number of inobject properties, to ensure that the
// performance of using object literals is not worse than using constructor
// functions, see crbug.com/v8/6211 for details.
const int kMaxFastLiteralDepth = …;
const int kMaxFastLiteralProperties = …;

enum BaseTaggedness : uint8_t { … };

enum class MemoryAccessKind : uint8_t { … };

size_t hash_value(MemoryAccessKind);

V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream&, MemoryAccessKind);

inline ExternalArrayType GetArrayTypeFromElementsKind(ElementsKind kind) { … }

inline int ExternalArrayElementSize(const ExternalArrayType element_type) { … }

}  // namespace compiler
}  // namespace internal
}  // namespace v8

// The biggest double value that fits within the int64_t/uint64_t value range.
// This is different from safe integer range in that there are gaps of integers
// in-between that cannot be represented as a double.
constexpr double kMaxDoubleRepresentableInt64 = …;
constexpr double kMinDoubleRepresentableInt64 = …;
constexpr double kMaxDoubleRepresentableUint64 = …;

// There is no (currently) available constexpr version of base::bit_cast, so
// we have to make do with constructing the -0.0 bits manually (by setting the
// sign bit to 1 and everything else to 0).
// TODO(leszeks): Revisit when upgrading to C++20.
constexpr int32_t kMinusZeroLoBits = …;
constexpr int32_t kMinusZeroHiBits = …;
constexpr int64_t kMinusZeroBits = …;

#endif  // V8_COMPILER_GLOBALS_H_