we are going to be getting away from creating new resource requests for every
instruction so no more need to keep track of a reqRemoveList and clean it up
every tick
first change in an optimization that will stop InOrder from allocating new memory for every instruction's
request to a resource. This gets expensive since every instruction needs to access ~10 requests before
graduation. Instead, the plan is to allocate just enough resource request objects to satisfy each resource's
bandwidth (e.g. the execution unit would need to allocate 3 resource request objects for a 1-issue pipeline
since on any given cycle it could have 2 read requests and 1 write request) and then let the instructions
contend and reuse those allocated requests. The end result is a smaller memory footprint for the InOrder model
and increased simulation performance
Maintain all information about an instruction's fault in the DynInst object rather
than any cpu-request object. Also, if there is a fault during the execution stage
then just save the fault inside the instruction and trap once the instruction
tries to graduate
There were several copies of similar functions that looked
like they all replicated reschedule(), so I replaced them
with direct calls. Keeping this separate from the previous
cset since there may be some subtle functional differences
if the code ever reschedules an event that is scheduled but
not squashed (though none were detected in the regressions).
Events need to be scheduled on the queue assigned
to the SimObject, not on the global queue (which
should be going away).
Also cleaned up a number of redundant expressions
that made the code unnecessarily verbose.
m5 doesnt do stats specific to binary and this resource request stat is probably only
useful for people who really know the ins/outs of the model anyway
add code to recognize memory stalls in resources and the pipeline as well
as squash a thread if there is a stall and we are in the switch on cache miss
model
This model currently only works in MIPS_SE mode, so it will take some effort
to clean it up and make it generally useful. Hopefully people are willing to
help make that happen!
