| //===-- llvm/MC/Register.h --------------------------------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_MC_REGISTER_H |
| #define LLVM_MC_REGISTER_H |
| |
| #include "llvm/ADT/DenseMapInfo.h" |
| #include <cassert> |
| |
| namespace llvm { |
| |
| /// An unsigned integer type large enough to represent all physical registers, |
| /// but not necessarily virtual registers. |
| using MCPhysReg = uint16_t; |
| |
| /// Wrapper class representing physical registers. Should be passed by value. |
| class MCRegister { |
| unsigned Reg; |
| |
| public: |
| MCRegister(unsigned Val = 0): Reg(Val) {} |
| |
| // Register numbers can represent physical registers, virtual registers, and |
| // sometimes stack slots. The unsigned values are divided into these ranges: |
| // |
| // 0 Not a register, can be used as a sentinel. |
| // [1;2^30) Physical registers assigned by TableGen. |
| // [2^30;2^31) Stack slots. (Rarely used.) |
| // [2^31;2^32) Virtual registers assigned by MachineRegisterInfo. |
| // |
| // Further sentinels can be allocated from the small negative integers. |
| // DenseMapInfo<unsigned> uses -1u and -2u. |
| |
| /// This is the portion of the positive number space that is not a physical |
| /// register. StackSlot values do not exist in the MC layer, see |
| /// Register::isStackSlot() for the more information on them. |
| /// |
| /// Note that isVirtualRegister() and isPhysicalRegister() cannot handle stack |
| /// slots, so if a variable may contains a stack slot, always check |
| /// isStackSlot() first. |
| static bool isStackSlot(unsigned Reg) { |
| return int(Reg) >= (1 << 30); |
| } |
| |
| /// Return true if the specified register number is in |
| /// the physical register namespace. |
| static bool isPhysicalRegister(unsigned Reg) { |
| assert(!isStackSlot(Reg) && "Not a register! Check isStackSlot() first."); |
| return int(Reg) > 0; |
| } |
| |
| /// Return true if the specified register number is in the physical register |
| /// namespace. |
| bool isPhysical() const { |
| return isPhysicalRegister(Reg); |
| } |
| |
| operator unsigned() const { |
| return Reg; |
| } |
| |
| unsigned id() const { |
| return Reg; |
| } |
| |
| bool isValid() const { |
| return Reg != 0; |
| } |
| |
| /// Comparisons between register objects |
| bool operator==(const MCRegister &Other) const { return Reg == Other.Reg; } |
| bool operator!=(const MCRegister &Other) const { return Reg != Other.Reg; } |
| |
| /// Comparisons against register constants. E.g. |
| /// * R == AArch64::WZR |
| /// * R == 0 |
| /// * R == VirtRegMap::NO_PHYS_REG |
| bool operator==(unsigned Other) const { return Reg == Other; } |
| bool operator!=(unsigned Other) const { return Reg != Other; } |
| bool operator==(int Other) const { return Reg == unsigned(Other); } |
| bool operator!=(int Other) const { return Reg != unsigned(Other); } |
| // MSVC requires that we explicitly declare these two as well. |
| bool operator==(MCPhysReg Other) const { return Reg == unsigned(Other); } |
| bool operator!=(MCPhysReg Other) const { return Reg != unsigned(Other); } |
| }; |
| |
| // Provide DenseMapInfo for MCRegister |
| template<> struct DenseMapInfo<MCRegister> { |
| static inline unsigned getEmptyKey() { |
| return DenseMapInfo<unsigned>::getEmptyKey(); |
| } |
| static inline unsigned getTombstoneKey() { |
| return DenseMapInfo<unsigned>::getTombstoneKey(); |
| } |
| static unsigned getHashValue(const MCRegister &Val) { |
| return DenseMapInfo<unsigned>::getHashValue(Val.id()); |
| } |
| static bool isEqual(const MCRegister &LHS, const MCRegister &RHS) { |
| return DenseMapInfo<unsigned>::isEqual(LHS.id(), RHS.id()); |
| } |
| }; |
| |
| } |
| |
| #endif // ifndef LLVM_MC_REGISTER_H |