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8 commits

Author SHA1 Message Date
Anthony Gutierrez
d3c33d91b6 cpu: remove local/globalHistoryBits params from branch pred
having separate params for the local/globalHistoryBits and the
local/globalPredictorSize can lead to inconsistencies if they
are not carefully set. this patch dervies the number of bits
necessary to index into the local/global predictors based on
their size.

the value of the localHistoryTableSize for the ARM O3 CPU has been
increased to 1024 from 64, which is more accurate for an A15 based
on some correlation against A15 hardware.
2013-05-14 18:39:47 -04:00
Nilay Vaish ext:(%2C%20Timothy%20Jones%20%3Ctimothy.jones%40cl.cam.ac.uk%3E)
dbeabedaf0 branch predictor: move out of o3 and inorder cpus
This patch moves the branch predictor files in the o3 and inorder directories
to src/cpu/pred. This allows sharing the branch predictor across different
cpu models.

This patch was originally posted by Timothy Jones in July 2010
but never made it to the repository.

--HG--
rename : src/cpu/o3/bpred_unit.cc => src/cpu/pred/bpred_unit.cc
rename : src/cpu/o3/bpred_unit.hh => src/cpu/pred/bpred_unit.hh
rename : src/cpu/o3/bpred_unit_impl.hh => src/cpu/pred/bpred_unit_impl.hh
rename : src/cpu/o3/sat_counter.hh => src/cpu/pred/sat_counter.hh
2013-01-24 12:28:51 -06:00
Andreas Sandberg
2cfe62adc4 cpu: Rename defer_registration->switched_out
The defer_registration parameter is used to prevent a CPU from
initializing at startup, leaving it in the "switched out" mode. The
name of this parameter (and the help string) is confusing. This patch
renames it to switched_out, which should be more descriptive.
2013-01-07 13:05:45 -05:00
Erik Tomusk
3dc7e4f496 TournamentBP: Fix some bugs with table sizes and counters
globalHistoryBits, globalPredictorSize, and choicePredictorSize are decoupled.
globalHistoryBits controls how much history is kept, global and choice
predictor sizes control how much of that history is used when accessing
predictor tables. This way, global and choice predictors can actually be
different sizes, and it is no longer possible to walk off the predictor arrays
and cause a seg fault.

There are now individual thresholds for choice, global, and local saturating
counters, so that taken/not taken decisions are correct even when the
predictors' counters' sizes are different.

The interface for localPredictorSize has been removed from TournamentBP because
the value can be calculated from localHistoryBits.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2012-12-06 09:31:06 -06:00
Andreas Hansson
88554790c3 Mem: Use cycles to express cache-related latencies
This patch changes the cache-related latencies from an absolute time
expressed in Ticks, to a number of cycles that can be scaled with the
clock period of the caches. Ultimately this patch serves to enable
future work that involves dynamic frequency scaling. As an immediate
benefit it also makes it more convenient to specify cache performance
without implicitly assuming a specific CPU core operating frequency.

The stat blocked_cycles that actually counter in ticks is now updated
to count in cycles.

As the timing is now rounded to the clock edges of the cache, there
are some regressions that change. Plenty of them have very minor
changes, whereas some regressions with a short run-time are perturbed
quite significantly. A follow-on patch updates all the statistics for
the regressions.
2012-10-15 08:10:54 -04:00
Mrinmoy Ghosh
6fc0094337 Cache: add a response latency to the caches
In the current caches the hit latency is paid twice on a miss. This patch lets
a configurable response latency be set of the cache for the backward path.
2012-09-25 11:49:41 -05:00
Mrinmoy Ghosh
7e104a1af2 prefetcher: Make prefetcher a sim object instead of it being a parameter on cache 2012-02-12 16:07:38 -06:00
Ronald Dreslinski
38ee552798 configs: actually add ARMv7a-like cpu/cache file 2012-01-26 16:44:43 -05:00