LLVM  9.0.0svn
Register.h
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1 //===-- llvm/CodeGen/Register.h ---------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_CODEGEN_REGISTER_H
10 #define LLVM_CODEGEN_REGISTER_H
11 
12 #include <cassert>
13 
14 namespace llvm {
15 
16 /// Wrapper class representing virtual and physical registers. Should be passed
17 /// by value.
18 class Register {
19  unsigned Reg;
20 
21 public:
22  Register(unsigned Val = 0): Reg(Val) {}
23 
24  /// Return true if the specified register number is in the virtual register
25  /// namespace.
26  bool isVirtual() const {
27  return int(Reg) < 0;
28  }
29 
30  /// Return true if the specified register number is in the physical register
31  /// namespace.
32  bool isPhysical() const {
33  return int(Reg) > 0;
34  }
35 
36  /// Convert a virtual register number to a 0-based index. The first virtual
37  /// register in a function will get the index 0.
38  unsigned virtRegIndex() const {
39  assert(isVirtual() && "Not a virtual register");
40  return Reg & ~(1u << 31);
41  }
42 
43  /// Convert a 0-based index to a virtual register number.
44  /// This is the inverse operation of VirtReg2IndexFunctor below.
45  static Register index2VirtReg(unsigned Index) {
46  return Register(Index | (1u << 31));
47  }
48 
49  operator unsigned() const {
50  return Reg;
51  }
52 
53  bool isValid() const {
54  return Reg != 0;
55  }
56 };
57 
58 }
59 
60 #endif
unsigned virtRegIndex() const
Convert a virtual register number to a 0-based index.
Definition: Register.h:38
This class represents lattice values for constants.
Definition: AllocatorList.h:23
bool isPhysical() const
Return true if the specified register number is in the physical register namespace.
Definition: Register.h:32
bool isVirtual() const
Return true if the specified register number is in the virtual register namespace.
Definition: Register.h:26
static Register index2VirtReg(unsigned Index)
Convert a 0-based index to a virtual register number.
Definition: Register.h:45
Register(unsigned Val=0)
Definition: Register.h:22
bool isValid() const
Definition: Register.h:53
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
Wrapper class representing virtual and physical registers.
Definition: Register.h:18