1 // Copyright 2017 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_CODEGEN_REGLIST_H_ 6 #define V8_CODEGEN_REGLIST_H_ 7 8 #include <cstdint> 9 10 #include "src/base/bits.h" 11 #include "src/base/template-utils.h" 12 13 namespace v8 { 14 namespace internal { 15 16 // Register configurations. 17 #if V8_TARGET_ARCH_ARM64 18 using RegList = uint64_t; 19 #else 20 using RegList = uint32_t; 21 #endif 22 23 // Get the number of registers in a given register list. NumRegs(RegList list)24constexpr int NumRegs(RegList list) { 25 return base::bits::CountPopulation(list); 26 } 27 28 namespace detail { 29 // Combine two RegLists by building the union of the contained registers. 30 // TODO(clemensb): Replace by constexpr lambda once we have C++17. CombineRegListsHelper(RegList list1,RegList list2)31constexpr RegList CombineRegListsHelper(RegList list1, RegList list2) { 32 return list1 | list2; 33 } 34 } // namespace detail 35 36 // Combine several RegLists by building the union of the contained registers. 37 template <typename... RegLists> CombineRegLists(RegLists...lists)38constexpr RegList CombineRegLists(RegLists... lists) { 39 return base::fold(detail::CombineRegListsHelper, 0, lists...); 40 } 41 42 } // namespace internal 43 } // namespace v8 44 45 #endif // V8_CODEGEN_REGLIST_H_ 46