memory_trace.cpp

#include "memory_trace.h"
#include <cassert>

MemoryTrace::MemoryTrace(processor_t *parents_cpu) {
	cpu = parents_cpu;
	read_from_writes = 0;
	unique_writes = 0;
	observes = 0;
	operates = 0;
}

MemoryTrace::~MemoryTrace() {
	//delete read_set;
	//delete write_set;
}

uinteger_t MemoryTrace::getHighData(generic_transaction_t *mop) {
	return ((SIM_get_mem_op_value_cpu(mop) >> 32) & 0xffffffff);
}

uinteger_t MemoryTrace::getLowData(generic_transaction_t *mop) {
	return (SIM_get_mem_op_value_cpu(mop) & 0xffffffff);
}

void MemoryTrace::OperateMemoryWrite(generic_transaction_t *mop) {
	x86_memory_transaction_t* xmop = (x86_memory_transaction_t*)mop;
	if (xmop->access_type == X86_Vanilla) {
		if(xmop->mode != Sim_CPU_Mode_User)
		{
			cout << "Sim_CPU_Mode ==> " << xmop->mode << endl;
		}
		operates++;
		physical_address_t addr = mop->physical_address;
		physical_address_t addr4 = mop->physical_address + 4;
		physical_address_t wordAddr = (addr & ~3);
		physical_address_t wordAddr4 = wordAddr + 4;
		int size = mop->size;
		
		switch (size) {
			case 8:
				if (write_set.find(wordAddr4) == write_set.end()) {
					unique_writes++;
					MemOp* memop1 = new MemOp(cpu, (addr4), 4, getHighData(mop));
					MemOp* memop2 = new MemOp(cpu, addr, 4, getLowData(mop));
					write_set[wordAddr4] = memop1;
					write_set[wordAddr] = memop2;
					mop->ignore = 1;
				} else {
					if (write_set.find(wordAddr) == write_set.end()) {
						MemOp* memop = new MemOp(cpu, addr, 4, getLowData(mop));
						write_set[addr & ~3] = memop;
					}
					write_set[wordAddr4]->setData(addr4, 4, getHighData(mop));
					write_set[addr & ~3]->setData(addr,  4, getLowData(mop));
					mop->ignore = 1;
				}
				break;
			case 4: case 2: case 1:
				if (write_set.find(addr & ~3) == write_set.end()) {
					unique_writes++;
					uinteger_t value = (size == 4) ? SIM_get_mem_op_value_cpu(mop)
							: SIM_get_mem_op_value_le(mop);
					
					if (size < 4) { //implicitly we must read the value
						if (read_set.find(addr & ~3) == read_set.end()) {
							read_set[addr & ~3] = '0';
						}
					}
					MemOp* memop = new MemOp(cpu, addr, size, value);
					write_set[addr & ~3] = memop;
					mop->ignore = 1;
				} else {
					uinteger_t value = (size == 4) ? SIM_get_mem_op_value_cpu(mop)
							: SIM_get_mem_op_value_le(mop);
					write_set[addr & ~3]->setData(addr, size, value);
					mop->ignore = 1;
				}
				break;
			default:
				cout << "write size == " << size << endl;
				assert(0);
				break;
		}
	}
}

void MemoryTrace::OperateMemoryRead(generic_transaction_t *mop) {
	x86_memory_transaction_t* xmop = (x86_memory_transaction_t*)mop;
	if (xmop->access_type == X86_Vanilla) {
		operates++;
		if (mop->size > 4) {
			//cout << "mop read size == " << mop->size << " on processor " << SIM_get_processor_number(cpu) << endl;
		}
		mop->inquiry = 1;
		mop->speculative = 1;
	} else {
		//cout << "access of type " << xmop->access_type << endl;
	}
}

void MemoryTrace::ObserveMemoryWrite(generic_transaction_t *mop) {
	/* this method shouldn't get called. Transactional writes are 
	 buffered until committal at which point the commit routine 
	 dumps all the writes into memory 
	 */
	assert(0);
}

void MemoryTrace::ObserveMemoryRead(generic_transaction_t *mop) {
	x86_memory_transaction_t* xmop = (x86_memory_transaction_t*)mop;
	if (xmop->access_type == X86_Vanilla) {
		//assert(mop->size <= 4);
		observes++;
		//x86_memory_transaction_t* xmop = (x86_memory_transaction_t*)mop;
		//assert(xmop->mode == Sim_CPU_Mode_User);

		/****************************************************************************
		 * ADD READ TO THE READ SET:
		 * - double word reads (8 bytes) are added as two seperate 32-bit entries
		 ****************************************************************************/
		physical_address_t addr = (mop->physical_address & ~3);
		if (read_set.find(addr) == read_set.end()) {
			read_set[addr] = '0';
		}
		//if its a double size read, add both to the read set (I think)
		if (mop->size == 8 && read_set.find(addr+4) == read_set.end()) {
			read_set[addr+4] = '0';
			//cout << "type ==> " << SIM_get_mem_op_type_name(mop->type) << endl;
		}

		/****************************************************************************
		 * CHECK IF READ IS IN WRITE SET:
		 * - if in write set hijack the operation and use that value instead of the
		 *   value present in main memory.
		 * - otherwise get from memory: this is safe as a committing transaction 
		 *   will abort a transaction reading from an updated value.
		 ****************************************************************************/
		if (write_set.find(addr) != write_set.end()) {
			//cout << "reading from write" << endl;
			read_from_writes++;
			/*if((int)mop->size != write_set[addr]->getSize()) {
			 cout << "Mop->size " << (int)mop->size << " writeSet->size " << write_set[addr]->getSize() << endl;
			 cout << "Memory read " << SIM_read_phys_memory(cpu, addr, mop->size) << endl;
			 cout << "Stored read " << write_set[addr]->getData(mop->physical_address, mop->size) << endl;
			 cout << "Mem[ws-size] " << SIM_read_phys_memory(cpu, addr, write_set[addr]->getSize()) << endl;
			 //assert(0);
			 }*/
			if (mop->size == 8) {
				/* if available grab the high data from the write_set */
				assert(write_set.find(addr + 4) != write_set.end());
				uint32 high_data = write_set[addr + 4]->getData(addr + 4, 4);
				uint32 low_data = write_set[addr]->getData(addr, 4);
				uinteger_t data = ((uinteger_t)high_data << 32) | (0xffffffff
						& low_data);
				SIM_set_mem_op_value_cpu(mop, data);
			} else if (mop->size == 4) {
				SIM_set_mem_op_value_cpu(mop, write_set[addr]->getData(
						mop->physical_address, mop->size));
			} else if (mop->size < 4) {
				SIM_set_mem_op_value_le(mop, write_set[addr]->getData(
						mop->physical_address, mop->size));
			} else {
				cout << "reading of size " << mop->size << endl;
				assert(0);
			}
		}
	}
}

void MemoryTrace::commit_writes() {
	map<physical_address_t, MemOp*>::const_iterator iter;
	for (iter=write_set.begin(); iter != write_set.end(); ++iter) {
		//cout << "commiting write " << iter->second << " " << iter->first << endl;
		physical_address_t addr = iter->second->getAddress();
		int size = iter->second->getSize();
		uint32 data = iter->second->getData(addr, size);
		SIM_write_phys_memory(cpu, addr, data, size);
	}
}

bool MemoryTrace::has_read(physical_address_t addr, int size) {

	if (read_set.find(addr & ~3) != read_set.end()) {
		return true;
	}
	if (size > 4) {
		if (read_set.find((addr & ~3) + 4) != read_set.end()) {
			return true;
		}
	}
	return false;
}

void MemoryTrace::clear() {
	//cout << "unique_reads " << read_set.size() << endl;
	//cout << "unique_writes " << unique_writes << endl;
	//cout << "read_from_writes " << read_from_writes << endl;
	//cout << "observes " << observes << endl;
	//cout << "operates " << operates << endl;
	read_from_writes = 0;
	unique_writes = 0;
	observes = 0;
	operates = 0;

	/* delete all of objects created in the readset */
	read_set.clear();

	/* delete all of objects created in the writeset */
	map<physical_address_t, MemOp*>::const_iterator iter;
	for (iter=write_set.begin(); iter != write_set.end(); ++iter) {
		delete iter->second;
	}
	write_set.clear();
}

int MemoryTrace::getWriteBufferSize() {
	//cout << "[" << cpu << "] write buffer size ==> " << write_set.size() << endl;
	return write_set.size();
}

physical_address_t MemoryTrace::getBufferedWrite(int index) {
	int position = 0;
	map<physical_address_t, MemOp*>::const_iterator iter;
	for (iter=write_set.begin(); iter != write_set.end(); ++iter) {
		if (position == index) {
			return iter->second->getAddress();
		} else
			position++;
	}
	return -1;
}

/** removes lines from a 32-byte cache */
void MemoryTrace::earlyRelease(int address) {
	//int rs_size = read_set.size();
	//int found = 0;

	for (int i = 0; i < 32; i += 4) {
		physical_address_t remAddress = SIM_logical_to_physical(cpu,
				Sim_DI_Data, logical_address_t(address + i));

		//if(read_set.find(remAddress) != read_set.end()) found++;

		read_set.erase(remAddress);
	}
	//cout << "read_set reduced by " << (rs_size - read_set.size()) << "(" << read_set.size() << "," << rs_size << ") [" << found << "]" << endl;
}

MemOp::MemOp(processor_t* cpu, physical_address_t address, int size, uint32 data) {
	mAddress = address & ~3;
	mSize = 4;
	int offset = address - mAddress;
	/* initialize to global memory values */
	mData = SIM_read_phys_memory(cpu, mAddress, 4);

	/* place write into appropriate chunk */
	setChunk(offset, size, data);
}

MemOp::~MemOp() {
}

uint32 MemOp::getData(physical_address_t address, int size) {
	/* check address bounds */
	assert(address >= mAddress);
	assert(address < (mAddress + 4));
	assert(size <= 4);

	/* alignment if half-word */
	if (size == 2)
		assert(address <= (mAddress + 2));

	int offset = address - mAddress;
	return getChunk(offset, size);
}

int MemOp::getSize(void) {
	return mSize;
}

physical_address_t MemOp::getAddress(void) {
	return mAddress;
}

void MemOp::setData(physical_address_t address, int size, uint32 data) {
	/* check address bounds */
	assert(address >= mAddress);
	assert(address < (mAddress + 4));
	assert(size <= 4);

	/* alignment if half-word */
	if (size == 2) {
		if (!(address <= (mAddress + 2)))
			cout << "addresses: " << hex << address << " " << mAddress << dec << endl;
		//assert(address <= (mAddress + 2));
	}

	/* having checked bounds and offsets set the chunk */
	int offset = address - mAddress;
	setChunk(offset, size, data);
}

void MemOp::setChunk(int offset, int size, uint32 data) {
	/* based on x86 little endianess */
	switch (size) {
	case 1:
		/* overwrite one of the bytes */
		switch (offset) {
		case 0:
			mData = (0xFFFFFF00 & mData) | (0xFF & data);
			break;
		case 1:
			mData = (0xFFFF00FF & mData) | ((0xFF & data) << 8);
			break;
		case 2:
			mData = (0xFF00FFFF & mData) | ((0xFF & data) << 16);
			break;
		case 3:
			mData = (0x00FFFFFF & mData) | ((0xFF & data) << 24);
			break;
		default:
			assert(0);
			break;
		}
		break;
	case 2:
		/* overwrite half word */
		switch (offset) {
		case 0:
			mData = (0xFFFF0000 & mData) | (0xFFFF & data);
			break;
		case 1:
			mData = (0xFF0000FF & mData) | ((0xFFFF & data) << 8);
			break;
		default:
			mData = (0x0000FFFF & mData) | ((0xFFFF & data) << 16);
			break;
			//default: assert(0); break;
		}
		break;
	case 4:
		/* overwrite the data completely */
		mData = data;
		break;
	default:
		assert(0);
		break;
	}
}

uint32 MemOp::getChunk(int offset, int size) {
	/* based on x86 little endianess */
	switch (size) {
	case 1:
		/* read one of the bytes */
		switch (offset) {
		case 0:
			return (0x000000FF & mData);
		case 1:
			return (0x000000FF & (mData >> 8));
		case 2:
			return (0x000000FF & (mData >> 16));
		case 3:
			return (0x000000FF & (mData >> 24));
		default:
			assert(0);
			break;
		}
		break;
	case 2:
		/* read half word */
		switch (offset) {
		case 0:
			return (0x0000FFFF & mData);
		case 1:
			return (0x0000FFFF & (mData >> 8));
		case 2:
			return (0x0000FFFF & (mData >> 16));
		default:
			assert(0);
			break;
		}
		break;
	case 4:
		/* read the data completely */
		return mData;
		break;
	default:
		assert(0);
		break;
	}
}