llvm-6502/lib/CodeGen/PhysRegTracker.h
2008-02-10 18:45:23 +00:00

74 lines
2.3 KiB
C++

//===-- llvm/CodeGen/PhysRegTracker.h - Physical Register Tracker -*- C++ -*-=//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements a physical register tracker. The tracker
// tracks physical register usage through addRegUse and
// delRegUse. isRegAvail checks if a physical register is available or
// not taking into consideration register aliases.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_PHYSREGTRACKER_H
#define LLVM_CODEGEN_PHYSREGTRACKER_H
#include "llvm/Target/TargetRegisterInfo.h"
namespace llvm {
class PhysRegTracker {
const TargetRegisterInfo* tri_;
std::vector<unsigned> regUse_;
public:
explicit PhysRegTracker(const TargetRegisterInfo& tri)
: tri_(&tri),
regUse_(tri_->getNumRegs(), 0) {
}
PhysRegTracker(const PhysRegTracker& rhs)
: tri_(rhs.tri_),
regUse_(rhs.regUse_) {
}
const PhysRegTracker& operator=(const PhysRegTracker& rhs) {
tri_ = rhs.tri_;
regUse_ = rhs.regUse_;
return *this;
}
void addRegUse(unsigned physReg) {
assert(TargetRegisterInfo::isPhysicalRegister(physReg) &&
"should be physical register!");
++regUse_[physReg];
for (const unsigned* as = tri_->getAliasSet(physReg); *as; ++as)
++regUse_[*as];
}
void delRegUse(unsigned physReg) {
assert(TargetRegisterInfo::isPhysicalRegister(physReg) &&
"should be physical register!");
assert(regUse_[physReg] != 0);
--regUse_[physReg];
for (const unsigned* as = tri_->getAliasSet(physReg); *as; ++as) {
assert(regUse_[*as] != 0);
--regUse_[*as];
}
}
bool isRegAvail(unsigned physReg) const {
assert(TargetRegisterInfo::isPhysicalRegister(physReg) &&
"should be physical register!");
return regUse_[physReg] == 0;
}
};
} // End llvm namespace
#endif