15fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// Copyright 2014 the V8 project authors. All rights reserved. 25fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// Use of this source code is governed by a BSD-style license that can be 35fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// found in the LICENSE file. 45fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 55fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org#ifndef V8_BASE_FLAGS_H_ 65fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org#define V8_BASE_FLAGS_H_ 75fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 8ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org#include "src/base/compiler-specific.h" 95fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 105fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.orgnamespace v8 { 115fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.orgnamespace base { 125fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 135fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// The Flags class provides a type-safe way of storing OR-combinations of enum 14ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org// values. The Flags<T, S> class is a template class, where T is an enum type, 15ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org// and S is the underlying storage type (usually int). 165fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// 175fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// The traditional C++ approach for storing OR-combinations of enum values is to 185fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// use an int or unsigned int variable. The inconvenience with this approach is 195fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// that there's no type checking at all; any enum value can be OR'd with any 205fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// other enum value and passed on to a function that takes an int or unsigned 215fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org// int. 22ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.orgtemplate <typename T, typename S = int> 23ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.orgclass Flags FINAL { 245fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org public: 255fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org typedef T flag_type; 26ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org typedef S mask_type; 275fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 285fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags() : mask_(0) {} 295fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags(flag_type flag) : mask_(flag) {} // NOLINT(runtime/explicit) 305fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org explicit Flags(mask_type mask) : mask_(mask) {} 315fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 325fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags& operator&=(const Flags& flags) { 335fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org mask_ &= flags.mask_; 345fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org return *this; 355fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org } 365fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags& operator|=(const Flags& flags) { 375fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org mask_ |= flags.mask_; 385fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org return *this; 395fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org } 405fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags& operator^=(const Flags& flags) { 415fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org mask_ ^= flags.mask_; 425fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org return *this; 435fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org } 445fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 455fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags operator&(const Flags& flags) const { return Flags(*this) &= flags; } 465fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags operator|(const Flags& flags) const { return Flags(*this) |= flags; } 475fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags operator^(const Flags& flags) const { return Flags(*this) ^= flags; } 485fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 495fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags& operator&=(flag_type flag) { return operator&=(Flags(flag)); } 505fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags& operator|=(flag_type flag) { return operator|=(Flags(flag)); } 515fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags& operator^=(flag_type flag) { return operator^=(Flags(flag)); } 525fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 535fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags operator&(flag_type flag) const { return operator&(Flags(flag)); } 545fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags operator|(flag_type flag) const { return operator|(Flags(flag)); } 555fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags operator^(flag_type flag) const { return operator^(Flags(flag)); } 565fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 575fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org Flags operator~() const { return Flags(~mask_); } 585fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 595fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org operator mask_type() const { return mask_; } 605fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org bool operator!() const { return !mask_; } 615fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 625fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org private: 635fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org mask_type mask_; 645fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org}; 655fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 665fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 675fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org#define DEFINE_OPERATORS_FOR_FLAGS(Type) \ 6821d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator&(Type::flag_type lhs, \ 6921d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org Type::flag_type rhs)ALLOW_UNUSED WARN_UNUSED_RESULT; \ 7021d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator&(Type::flag_type lhs, Type::flag_type rhs) { \ 7121d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org return Type(lhs) & rhs; \ 725fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org } \ 7321d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator&(Type::flag_type lhs, \ 7421d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org const Type& rhs)ALLOW_UNUSED WARN_UNUSED_RESULT; \ 7521d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator&(Type::flag_type lhs, const Type& rhs) { \ 765fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org return rhs & lhs; \ 775fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org } \ 78ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org inline void operator&(Type::flag_type lhs, Type::mask_type rhs)ALLOW_UNUSED; \ 795fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org inline void operator&(Type::flag_type lhs, Type::mask_type rhs) {} \ 8021d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator|(Type::flag_type lhs, Type::flag_type rhs) \ 81ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org ALLOW_UNUSED WARN_UNUSED_RESULT; \ 8221d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator|(Type::flag_type lhs, Type::flag_type rhs) { \ 8321d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org return Type(lhs) | rhs; \ 845fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org } \ 8521d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator|(Type::flag_type lhs, const Type& rhs) \ 86ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org ALLOW_UNUSED WARN_UNUSED_RESULT; \ 8721d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator|(Type::flag_type lhs, const Type& rhs) { \ 885fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org return rhs | lhs; \ 895fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org } \ 90ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org inline void operator|(Type::flag_type lhs, Type::mask_type rhs) \ 91ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org ALLOW_UNUSED; \ 925fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org inline void operator|(Type::flag_type lhs, Type::mask_type rhs) {} \ 9321d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator^(Type::flag_type lhs, Type::flag_type rhs) \ 94ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org ALLOW_UNUSED WARN_UNUSED_RESULT; \ 9521d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator^(Type::flag_type lhs, Type::flag_type rhs) { \ 9621d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org return Type(lhs) ^ rhs; \ 9721d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org } inline Type operator^(Type::flag_type lhs, const Type& rhs) \ 98ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org ALLOW_UNUSED WARN_UNUSED_RESULT; \ 9921d700eedcdd6570eff22ece724b63a5eefe78cbmachenbach@chromium.org inline Type operator^(Type::flag_type lhs, const Type& rhs) { \ 1005fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org return rhs ^ lhs; \ 101ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org } inline void operator^(Type::flag_type lhs, Type::mask_type rhs) \ 102ada3a6017e603965f87fa34f6e2fa60379e8d697machenbach@chromium.org ALLOW_UNUSED; \ 1035fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org inline void operator^(Type::flag_type lhs, Type::mask_type rhs) {} 1045fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 1055fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org} // namespace base 1065fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org} // namespace v8 1075fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org 1085fc1eed70f85bd1e9d0833742945798d6ef49cf0machenbach@chromium.org#endif // V8_BASE_FLAGS_H_ 109