llvm-6502/lib/CodeGen/MachineRegisterInfo.cpp
Chris Lattner 62ed6b9ade Implement automatically updated def/use lists for all MachineInstr register
operands.  The lists are currently kept in MachineRegisterInfo, but it does
not yet provide an iterator interface to them.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45477 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-01 01:12:31 +00:00

47 lines
1.6 KiB
C++

//===-- lib/Codegen/MachineRegisterInfo.cpp -------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Implementation of the MachineRegisterInfo class.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineRegisterInfo.h"
using namespace llvm;
MachineRegisterInfo::MachineRegisterInfo(const MRegisterInfo &MRI) {
VRegInfo.reserve(256);
UsedPhysRegs.resize(MRI.getNumRegs());
// Create the physreg use/def lists.
PhysRegUseDefLists = new MachineOperand*[MRI.getNumRegs()];
memset(PhysRegUseDefLists, 0, sizeof(MachineOperand*)*MRI.getNumRegs());
}
MachineRegisterInfo::~MachineRegisterInfo() {
#ifndef NDEBUG
for (unsigned i = 0, e = VRegInfo.size(); i != e; ++i)
assert(VRegInfo[i].second == 0 && "Vreg use list non-empty still?");
#endif
delete [] PhysRegUseDefLists;
}
/// HandleVRegListReallocation - We just added a virtual register to the
/// VRegInfo info list and it reallocated. Update the use/def lists info
/// pointers.
void MachineRegisterInfo::HandleVRegListReallocation() {
// The back pointers for the vreg lists point into the previous vector.
// Update them to point to their correct slots.
for (unsigned i = 0, e = VRegInfo.size(); i != e; ++i) {
MachineOperand *List = VRegInfo[i].second;
if (!List) continue;
// Update the back-pointer to be accurate once more.
List->Contents.Reg.Prev = &VRegInfo[i].second;
}
}