void OMR::Power::RegisterDependencyConditions::bookKeepingRegisterUses(TR::Instruction *instr, TR::CodeGenerator *cg)
{
// *this swipeable for debugging purposes
TR::Register *virtReg;
TR::RealRegister::RegNum regNum;
TR::RegisterDependencyConditions *assoc;
int numAssoc = 0;
if (instr->getOpCodeValue() == TR::InstOpCode::assocreg)
return;
// Don't track associations or emit assocregs in outlined code
// Register assigner can save/restore associations across outlined sections properly, however no such mechanism exists for instruction selection
// so we don't want these associations to clobber the associations that were set in main line code, which are more important
// TODO: Fix this by saving/restoring the associations in swapInstructionListsWithCompilation()
bool isOOL = cg->getIsInOOLSection();
TR::Machine *machine = cg->machine();
assoc = !isOOL ? new (cg->trHeapMemory()) TR::RegisterDependencyConditions(0,_addCursorForPre, cg->trMemory()) : 0;
for (int i = 0; i < _addCursorForPre; i++)
{
virtReg = _preConditions->getRegisterDependency(i)->getRegister();
regNum = _preConditions->getRegisterDependency(i)->getRealRegister();
if (!isOOL)
{
// Add to the association condition when the association is changed
// from one virtual register to another
if (machine->getVirtualAssociatedWithReal(regNum) != virtReg && machine->getVirtualAssociatedWithReal(regNum) != 0)
{
assoc->addPostCondition(machine->getVirtualAssociatedWithReal(regNum), regNum);
numAssoc++;
}
// Keep track of the virtual register map to real registers!
machine->setVirtualAssociatedWithReal(regNum, virtReg);
}
instr->useRegister(virtReg);
if (!isOOL)
{
cg->setRealRegisterAssociation(virtReg, regNum);
if (_preConditions->getRegisterDependency(i)->getExcludeGPR0())
cg->addRealRegisterInterference(virtReg, TR::RealRegister::gr0);
}
}
if (numAssoc > 0)
{
// Emit an AssocRegs instruction to track the previous association
assoc->setNumPostConditions(numAssoc, cg->trMemory());
generateDepInstruction(cg, TR::InstOpCode::assocreg, instr->getNode(), assoc, instr->getPrev());
}
for (int j = 0; j < _addCursorForPost; j++)
{
virtReg = _postConditions->getRegisterDependency(j)->getRegister();
regNum = _postConditions->getRegisterDependency(j)->getRealRegister();
instr->useRegister(virtReg);
if (!isOOL)
{
cg->setRealRegisterAssociation(virtReg, regNum);
if (_postConditions->getRegisterDependency(j)->getExcludeGPR0())
cg->addRealRegisterInterference(virtReg, TR::RealRegister::gr0);
}
}
}
void OMR::X86::Instruction::assignRegisters(TR_RegisterKinds kindsToBeAssigned)
{
if (!self()->getDependencyConditions())
{
// Fast path when there are no dependency conditions.
//
return;
}
if (self()->getOpCodeValue() != ASSOCREGS)
{
self()->aboutToAssignRegDeps();
if ((self()->cg()->getAssignmentDirection() == self()->cg()->Backward))
{
self()->getDependencyConditions()->assignPostConditionRegisters(self(), kindsToBeAssigned, self()->cg());
self()->getDependencyConditions()->assignPreConditionRegisters(self(), kindsToBeAssigned, self()->cg());
}
else
{
self()->getDependencyConditions()->assignPreConditionRegisters(self()->getPrev(), kindsToBeAssigned, self()->cg());
self()->getDependencyConditions()->assignPostConditionRegisters(self(), kindsToBeAssigned, self()->cg());
}
}
else if ((self()->getOpCodeValue() == ASSOCREGS) && self()->cg()->enableRegisterAssociations())
{
if (kindsToBeAssigned & TR_GPR_Mask)
{
TR::Machine *machine = self()->cg()->machine();
// First traverse the existing associations and remove them
// so that they don't interfere with the new ones
//
for (int i = TR::RealRegister::FirstGPR;
i <= TR::RealRegister::LastAssignableGPR;
++i)
{
// Skip non-assignable registers
//
if (machine->getX86RealRegister((TR::RealRegister::RegNum)i)->getState() == TR::RealRegister::Locked)
continue;
TR::Register *virtReg = machine->getVirtualAssociatedWithReal((TR::RealRegister::RegNum)i);
if (virtReg)
{
virtReg->setAssociation(TR::RealRegister::NoReg);
}
}
// Next loop through and set up the new associations (both on the machine
// and by associating the virtual registers with their real dependencies)
//
TR_X86RegisterDependencyGroup *depGroup = self()->getDependencyConditions()->getPostConditions();
for (int j = 0; j < self()->getDependencyConditions()->getNumPostConditions(); ++j)
{
TR::RegisterDependency *dep = depGroup->getRegisterDependency(j);
machine->setVirtualAssociatedWithReal(dep->getRealRegister(), dep->getRegister());
}
machine->setGPRWeightsFromAssociations();
}
}
}