1 //===-- llvm/CodeGen/SSARegMap.h --------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Map register numbers to register classes that are correctly sized (typed) to
11 // hold the information. Assists register allocation. Contained by
12 // MachineFunction, should be deleted by register allocator when it is no
15 //===----------------------------------------------------------------------===//
17 #ifndef LLVM_CODEGEN_SSAREGMAP_H
18 #define LLVM_CODEGEN_SSAREGMAP_H
20 #include "llvm/Target/MRegisterInfo.h"
21 #include "llvm/ADT/IndexedMap.h"
25 class TargetRegisterClass;
28 IndexedMap<const TargetRegisterClass*, VirtReg2IndexFunctor> RegClassMap;
29 IndexedMap<std::pair<unsigned, unsigned>, VirtReg2IndexFunctor> RegSubIdxMap;
33 SSARegMap() : NextRegNum(MRegisterInfo::FirstVirtualRegister) { }
35 const TargetRegisterClass* getRegClass(unsigned Reg) {
36 return RegClassMap[Reg];
39 /// createVirtualRegister - Create and return a new virtual register in the
40 /// function with the specified register class.
42 unsigned createVirtualRegister(const TargetRegisterClass *RegClass) {
43 assert(RegClass && "Cannot create register without RegClass!");
44 RegClassMap.grow(NextRegNum);
45 RegClassMap[NextRegNum] = RegClass;
46 RegSubIdxMap.grow(NextRegNum);
47 RegSubIdxMap[NextRegNum] = std::make_pair(0,0);
51 unsigned getLastVirtReg() const {
52 return NextRegNum - 1;
55 void setIsSubRegister(unsigned Reg, unsigned SuperReg, unsigned SubIdx) {
56 RegSubIdxMap[Reg] = std::make_pair(SuperReg, SubIdx);
59 bool isSubRegister(unsigned Reg) const {
60 return RegSubIdxMap[Reg].first != 0;
63 unsigned getSuperRegister(unsigned Reg) const {
64 return RegSubIdxMap[Reg].first;
67 unsigned getSubRegisterIndex(unsigned Reg) const {
68 return RegSubIdxMap[Reg].second;
72 } // End llvm namespace