Eliminate uneeded lookups by passing a Virt2PhysMap::iterator instead

of the virtual register to certain functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11143 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Alkis Evlogimenos 2004-02-06 03:15:40 +00:00
parent 99dcc1da86
commit 54d23c754a

View File

@ -176,12 +176,13 @@ namespace {
/// assignVirt2PhysReg - assigns the free physical register to
/// the virtual register passed as arguments
void assignVirt2PhysReg(unsigned virtReg, unsigned physReg);
Virt2PhysMap::iterator
assignVirt2PhysReg(unsigned virtReg, unsigned physReg);
/// clearVirtReg - free the physical register associated with this
/// virtual register and disassociate virtual->physical and
/// physical->virtual mappings
void clearVirtReg(unsigned virtReg);
void clearVirtReg(Virt2PhysMap::iterator it);
/// assignVirt2StackSlot - assigns this virtual register to a
/// stack slot
@ -192,12 +193,13 @@ namespace {
int getStackSlot(unsigned virtReg);
/// spillVirtReg - spills the virtual register
void spillVirtReg(unsigned virtReg);
void spillVirtReg(Virt2PhysMap::iterator it);
/// loadPhysReg - loads to the physical register the value of
/// the virtual register specifed. Virtual register must have
/// an assigned stack slot
void loadVirt2PhysReg(unsigned virtReg, unsigned physReg);
Virt2PhysMap::iterator
loadVirt2PhysReg(unsigned virtReg, unsigned physReg);
void printVirtRegAssignment() const {
std::cerr << "register assignment:\n";
@ -460,7 +462,7 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
continue;
}
typedef std::vector<unsigned> Regs;
typedef std::vector<Virt2PhysMap::iterator> Regs;
Regs toClear;
Regs toSpill;
@ -473,19 +475,19 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
if (op.isVirtualRegister() && op.isUse()) {
unsigned virtReg = op.getAllocatedRegNum();
unsigned physReg = 0;
Virt2PhysMap::const_iterator it = v2pMap_.find(virtReg);
Virt2PhysMap::iterator it = v2pMap_.find(virtReg);
if (it != v2pMap_.end()) {
physReg = it->second;
}
else {
physReg = getFreeTempPhysReg(virtReg);
loadVirt2PhysReg(virtReg, physReg);
it = loadVirt2PhysReg(virtReg, physReg);
// we will clear uses that are not also defs
// before we allocate registers the defs
if (op.isDef())
toSpill.push_back(virtReg);
toSpill.push_back(it);
else
toClear.push_back(virtReg);
toClear.push_back(it);
}
(*currentInstr_)->SetMachineOperandReg(i, physReg);
}
@ -504,16 +506,16 @@ bool RA::runOnMachineFunction(MachineFunction &fn) {
assert(!op.isUse() && "we should not have uses here!");
unsigned virtReg = op.getAllocatedRegNum();
unsigned physReg = 0;
Virt2PhysMap::const_iterator it = v2pMap_.find(virtReg);
Virt2PhysMap::iterator it = v2pMap_.find(virtReg);
if (it != v2pMap_.end()) {
physReg = it->second;
}
else {
physReg = getFreeTempPhysReg(virtReg);
assignVirt2PhysReg(virtReg, physReg);
it = assignVirt2PhysReg(virtReg, physReg);
// need to spill this after we are done with
// this instruction
toSpill.push_back(virtReg);
toSpill.push_back(it);
}
(*currentInstr_)->SetMachineOperandReg(i, physReg);
}
@ -774,17 +776,20 @@ unsigned RA::getFreeTempPhysReg(unsigned virtReg)
return 0;
}
void RA::assignVirt2PhysReg(unsigned virtReg, unsigned physReg)
RA::Virt2PhysMap::iterator
RA::assignVirt2PhysReg(unsigned virtReg, unsigned physReg)
{
bool inserted = v2pMap_.insert(std::make_pair(virtReg, physReg)).second;
bool inserted;
Virt2PhysMap::iterator it;
tie(it, inserted) = v2pMap_.insert(std::make_pair(virtReg, physReg));
assert(inserted && "attempting to assign a virt->phys mapping to an "
"already mapped register");
prt_.addPhysRegUse(physReg);
return it;
}
void RA::clearVirtReg(unsigned virtReg)
void RA::clearVirtReg(Virt2PhysMap::iterator it)
{
Virt2PhysMap::iterator it = v2pMap_.find(virtReg);
assert(it != v2pMap_.end() &&
"attempting to clear a not allocated virtual register");
unsigned physReg = it->second;
@ -804,8 +809,9 @@ void RA::assignVirt2StackSlot(unsigned virtReg)
"attempt to assign stack slot to already assigned register?");
// if the virtual register was previously assigned clear the mapping
// and free the virtual register
if (v2pMap_.count(virtReg)) {
clearVirtReg(virtReg);
Virt2PhysMap::iterator it = v2pMap_.find(virtReg);
if (it != v2pMap_.end()) {
clearVirtReg(it);
}
}
@ -817,19 +823,23 @@ int RA::getStackSlot(unsigned virtReg)
return it->second;
}
void RA::spillVirtReg(unsigned virtReg)
void RA::spillVirtReg(Virt2PhysMap::iterator it)
{
assert(it != v2pMap_.end() &&
"attempt to spill a not allocated virtual register");
unsigned virtReg = it->first;
DEBUG(std::cerr << "\t\t\tspilling register: " << virtReg);
const TargetRegisterClass* rc = mf_->getSSARegMap()->getRegClass(virtReg);
int frameIndex = getStackSlot(virtReg);
DEBUG(std::cerr << " to stack slot #" << frameIndex << '\n');
++numSpilled;
instrAdded_ += mri_->storeRegToStackSlot(*currentMbb_, currentInstr_,
v2pMap_[virtReg], frameIndex, rc);
clearVirtReg(virtReg);
it->second, frameIndex, rc);
clearVirtReg(it);
}
void RA::loadVirt2PhysReg(unsigned virtReg, unsigned physReg)
RA::Virt2PhysMap::iterator
RA::loadVirt2PhysReg(unsigned virtReg, unsigned physReg)
{
DEBUG(std::cerr << "\t\t\tloading register: " << virtReg);
const TargetRegisterClass* rc = mf_->getSSARegMap()->getRegClass(virtReg);
@ -838,7 +848,7 @@ void RA::loadVirt2PhysReg(unsigned virtReg, unsigned physReg)
++numReloaded;
instrAdded_ += mri_->loadRegFromStackSlot(*currentMbb_, currentInstr_,
physReg, frameIndex, rc);
assignVirt2PhysReg(virtReg, physReg);
return assignVirt2PhysReg(virtReg, physReg);
}
FunctionPass* llvm::createLinearScanRegisterAllocator() {