Commands_High_Level_Algorithm

Read function high level algorithm:
Check for a valid in the set of data
If valid data, loop through the line of data for the set
	Check to see if any of the tags in the set match
	If, MESI is not invalid and tags match
		Read the data and update the LRU bits
		Return a hit
	Else if, check to see if the line of data is full
		If the line is full, find a line to evict
			Check the for the least recently used line to evict
			Write back the evicted line to L2
		Read data from L2
	Else, find an empty slot in the set
		Check for an invalid line
		If, the line is invalid
			Write the tag to the invalid slot
			Check the MESI for the tag to shared
			Increase the valid count
Else invalid data for the whole set,
	Read the data in from L2
	Set the line to shared
	Increase the valid count
Update the LRU bits
Return from read function

Write data high level algorithm:
Check to see it if the set is invalid
	If the set is invalid, handle the write miss
		Loop through set of data and check for invalid line
			If the line is invalid,
				Read from L2
				Set the MESI to shared for the line
				Write to L2
				Set the MESI to exclusive for the line
				Update the LRU bits for the set
				Increase the valid count
				Return form handling write miss
			Return miss
	Else, check for valid lines in the set
		Check to see if the tags match
		If the tags match,
			Write to the line and set MESI for the line to modified
			Update the LRU bits for the set
			Return a hit
		Check to see if the set is full
		If the line is full,
			Handle a write eviction
			Evict the least recently used line and invalidate it
			Decrement the valid count
		Handle the write miss
		Loop through set of data and check for invalid line
			If the line is invalid,
				Read from L2
				Set the MESI to shared for the line
				Write to L2
				Set the MESI to exclusive for the line
				Update the LRU bits for the set
				Increase the valid count
				Return form handling write miss

Invalidate High Level Algorithm:
Loop through the lines in the set 
Check to see if the tag matches the line
	If the tag matches,
		Check the MESI state for the line
		Case of modified and exclusive
			Write to the L2
			Break
		Case of shared
			Break
		Invalidate the line
		Decrement the count

Read from L2 High Level Algorithm:
Loop through the lines in the set
Check to see if the tag matches the line
	If the tag matches
		Check to see if the line has been modified
		If the line is in the modified state
			Return data to L2
		Set the MESI state to shared
		Return a hit