void LinearScan::removeUnusedSpillsAux(Trace* trace) { IRInstruction::List& instList = trace->getInstructionList(); for (IRInstruction::Iterator it = instList.begin(); it != instList.end(); ) { IRInstruction::Iterator next = it; ++next; IRInstruction* inst = *it; if (inst->getOpcode() == Spill && inst->getDst()->getUseCount() == 0) { instList.erase(it); SSATmp* src = inst->getSrc(0); if (src->decUseCount() == 0) { Opcode srcOpc = src->getInstruction()->getOpcode(); // Not all instructions are able to take noreg as its dest // reg. We pick LdLoc and IncRef because they occur often. if (srcOpc == IncRef || srcOpc == LdLoc) { for (int locIndex = 0; locIndex < src->numNeededRegs(); ++locIndex) { src->setReg(InvalidReg, locIndex); } } } } it = next; } }
void LinearScan::removeUnusedSpills() { for (SlotInfo& slot : m_slots) { IRInstruction* spill = slot.m_spillTmp->getInstruction(); if (spill->getDst()->getUseCount() == 0) { Block* block = spill->getBlock(); block->erase(block->iteratorTo(spill)); SSATmp* src = spill->getSrc(0); if (src->decUseCount() == 0) { Opcode srcOpc = src->getInstruction()->getOpcode(); // Not all instructions are able to take noreg as its dest // reg. We pick LdLoc and IncRef because they occur often. if (srcOpc == IncRef || srcOpc == LdLoc) { for (int i = 0, n = src->numNeededRegs(); i < n; ++i) { src->setReg(InvalidReg, i); } } } } } }