What does bubble do

S2015 5,6,9 - stalling and registers
when can/can't you forward
hazards and their resolution
	branch misprediction - control hazard, triggered by (op->jXX dependency)
		solve via squashing (speculatively load instructions, use bubble to remove if wrong)
	load-use - data hazard, triggered by (load->use dependency)
		instr1 reads memory, instr2 uses that value in execute
		solve via one cycle of stalling and then forwarding
	return - control hazard, triggered by itself
		solve by waiting for memory before fetching (stall Fetch) - forward


data v control hazard

Dependency v hazard
	dep = characteristic of code
	haz = characteristic of ISA + Pipeline design

sram/dram - not this semester



cache equations
S2016 18 - cache equations
tracing hits/misses with list of addresses

cache and speed
	miss rate - want it low; associativity makes it low (usually)
	hit response time - want it fast; associativity makes it slow
	

for loop and cache (F2014 11+13)
F2014 12, 17, 19 - locality