src/third_party/v8/src/compiler/backend/register-allocation.h

// 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_COMPILER_BACKEND_REGISTER_ALLOCATION_H_
#define V8_COMPILER_BACKEND_REGISTER_ALLOCATION_H_

#include "src/codegen/register-configuration.h"
#include "src/zone/zone.h"

namespace v8 {
namespace internal {
namespace compiler {

enum class RegisterKind { kGeneral, kDouble };

inline int GetRegisterCount(const RegisterConfiguration* config,
                            RegisterKind kind) {
  switch (kind) {
    case RegisterKind::kGeneral:
      return config->num_general_registers();
    case RegisterKind::kDouble:
      return config->num_double_registers();
  }
}

inline int GetAllocatableRegisterCount(const RegisterConfiguration* config,
                                       RegisterKind kind) {
  switch (kind) {
    case RegisterKind::kGeneral:
      return config->num_allocatable_general_registers();
    case RegisterKind::kDouble:
      return config->num_allocatable_double_registers();
  }
}

inline const int* GetAllocatableRegisterCodes(
    const RegisterConfiguration* config, RegisterKind kind) {
  switch (kind) {
    case RegisterKind::kGeneral:
      return config->allocatable_general_codes();
    case RegisterKind::kDouble:
      return config->allocatable_double_codes();
  }
}

inline int ByteWidthForStackSlot(MachineRepresentation rep) {
  switch (rep) {
    case MachineRepresentation::kBit:
    case MachineRepresentation::kWord8:
    case MachineRepresentation::kWord16:
    case MachineRepresentation::kWord32:
    case MachineRepresentation::kFloat32:
      return kSystemPointerSize;
    case MachineRepresentation::kTaggedSigned:
    case MachineRepresentation::kTaggedPointer:
    case MachineRepresentation::kTagged:
    case MachineRepresentation::kCompressedPointer:
    case MachineRepresentation::kCompressed:
      // TODO(ishell): kTaggedSize once half size locations are supported.
      return kSystemPointerSize;
    case MachineRepresentation::kWord64:
    case MachineRepresentation::kFloat64:
      return kDoubleSize;
    case MachineRepresentation::kSimd128:
      return kSimd128Size;
    case MachineRepresentation::kNone:
      break;
  }
  UNREACHABLE();
}

class RegisterAllocationData : public ZoneObject {
 public:
  enum Type {
    kTopTier,
    kMidTier,
  };

  Type type() const { return type_; }

 protected:
  explicit RegisterAllocationData(Type type) : type_(type) {}

 private:
  Type type_;
};

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

#endif  // V8_COMPILER_BACKEND_REGISTER_ALLOCATION_H_