The temporal compactor was never initialized.
There were more possible indexes to the prec/succ vectors than
entries, so a block distance of zero would seg fault.
When checking for an address the wrong vector was being used.
From the original paper, "The prediction mechanism searches for
the PC of the accessed instruction in the index table"
Change-Id: I3c3aceac3c0adbbe8aef5c634c88cb35ba7487be
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28487
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This patch fixes the following bugs:
- Previously when deltaPointer was 0 or 1, getting the last or penultimate deltas
would be wrong for non-pow2 deltas.size(). For example, if the last added delta
was to position 0, the previous should be in position 19, if deltas.size() = 20.
However, 0-1=4294967295, and 4294967295%20=15.
- When searching for the previous late and penultimate, the oldest entry was being
skipped.
Change-Id: Id800b60b77531ac4c2920bb90c15cc8cebb137a9
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24538
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Javier Bueno Hedo <javier.bueno@metempsy.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Add an invalidation function to the AssociativeSet, so that entries
can be properly invalidated by also invalidating their replacement
data.
Both setInvalid and reset have been merged into invalidate to
indicate users that they are using an incorrect approach by
generating compilation errors, and to match CacheBlk's naming
convention.
Change-Id: I568076a3b5adda8b1311d9498b086c0dab457a14
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24529
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Members `tc` and `ongoingTranslation` were uninitialized in the constructor for
`QueuedPrefetcher::DeferredPacket`. If `ongoingTranslation` is not initialized to
`false` by default, some translation requests from queued prefetchers are not
properly handled and executions are nondeterministic.
Change-Id: Ia278f9e74847d6b847984d47f6a45643bae57794
Signed-off-by: Isaac Sánchez Barrera <isaac.sanchez@bsc.es>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22844
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This patch adds a meta-prefetcher that enables gem5's cache models to
connect to multiple prefetchers. Sub-prefetchers still use the
probes-based interface and training can be controlled
independently. However, when the cache requests a prefetch packet, the
adaptor traverses the priority list of prefetchers and uses the first
prefetcher that is able to generate a prefetch.
Kudos to Mitch Hayenga for the original version of this patch.
Change-Id: I25569a834997e5404c7183ec995d212912c5dcdf
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18868
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reference:
Stephen Somogyi, Thomas F. Wenisch, Anastasia Ailamaki, and
Babak Falsafi. 2009. Spatio-temporal memory streaming.
In Proceedings of the 36th annual international symposium on
Computer architecture (ISCA '09). ACM, New York, NY, USA, 69-80.
Change-Id: I58cea1a7faa9391f8aa4469eb4973feabd31097a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/16423
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Error:
build/X86/mem/cache/prefetch/indirect_memory.cc:56:24:
error: result of comparison of constant -1 with expression
of type 'const ByteOrder' is always false
[-Werror,-Wtautological-constant-out-of-range-compare]
fatal_if(byteOrder == -1, "This prefetcher requires a defined ISA\n");
~~~~~~~~~ ^ ~~
build/X86/base/logging.hh:205:14: note: expanded from macro 'fatal_if'
if ((cond)) { \
^~~~
1 error generated.
Fix:
cast of constant (-1) used in comparison
Change-Id: I3deb154c2fe5b92c4ddf499176cb185c4ec7cf64
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17388
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Added additional information to the PrefetchInfo data structure
- Whether the event is triggered by a cache miss
- Whether the event is a write or a read
- Size of the data accessed
- Data accessed by the request
Change-Id: I070f3ffe837ea960a357388e7f2b8a61d7b2196c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/16583
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reference:
Towards Bandwidth-Efficient Prefetching with Slim AMPM.
Young, V., & Krishna, A. (2015). The 2nd Data Prefetching Championship.
Slim AMPM is composed of two prefetchers, the DPCT and the AMPM (both already
in gem5).
Change-Id: I6e868faf216e3e75231cf181d59884ed6f0d382a
Reviewed-on: https://gem5-review.googlesource.com/c/16383
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Based in the description of the following publication:
Akanksha Jain and Calvin Lin. 2013. Linearizing irregular memory accesses
for improved correlated prefetching. In Proceedings of the 46th Annual
IEEE/ACM International Symposium on Microarchitecture (MICRO-46). ACM,
New York, NY, USA, 247-259.
Change-Id: Ibeb6abc93ca40ad634df6ed5cf8becb0a49d1165
Reviewed-on: https://gem5-review.googlesource.com/c/15215
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reference:
Multi-level hardware prefetching using low complexity delta correlating
prediction tables with partial matching.
Marius Grannaes, Magnus Jahre, and Lasse Natvig. 2010.
In Proceedings of the 5th international conference on High Performance
Embedded Architectures and Compilers (HiPEAC'10)
Change-Id: I7b5d7ede9284862a427cfd5693a47652a69ed49d
Reviewed-on: https://gem5-review.googlesource.com/c/16062
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
The importer in Python 3 doesn't like the way we import SimObjects
from the global namespace. Convert the existing SimObject declarations
to import from m5.objects. As a side-effect, this makes these files
consistent with configuration files.
Change-Id: I11153502b430822130722839e1fa767b82a027aa
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15981
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
This implementation is based in the description available in:
Jinchun Kim, Seth H. Pugsley, Paul V. Gratz, A. L. Narasimha Reddy,
Chris Wilkerson, and Zeshan Chishti. 2016.
Path confidence based lookahead prefetching.
In The 49th Annual IEEE/ACM International Symposium on Microarchitecture
(MICRO-49). IEEE Press, Piscataway, NJ, USA, Article 60, 12 pages.
Change-Id: I4b8b54efef48ced7044bd535de9a69bca68d47d9
Reviewed-on: https://gem5-review.googlesource.com/c/14819
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Implementation of the Access Map Pattern Matching prefetcher
Based in the description of the following paper:
Access map pattern matching for high performance data cache prefetch.
Ishii, Y., Inaba, M., & Hiraki, K. (2011).
Journal of Instruction-Level Parallelism, 13, 1-24.
Change-Id: I0d4b7f7afc2ab4938bdd8755bfed26e26a28530c
Reviewed-on: https://gem5-review.googlesource.com/c/15096
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Prefetchers can be configured to operate with virtual or physical addreses.
The option can be configured through the "use_virtual_addresses" parameter
of the Prefetcher object.
Change-Id: I4f8c3687988afecc8a91c3c5b2d44cc0580f72aa
Reviewed-on: https://gem5-review.googlesource.com/c/14416
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Move the unordered_map outside of the PCTable, as it
belongs to the StridePrefetcher. By doing so we are
moving towards a table that ressembles the ones of
the Tags classes.
Some functions have been moved from the prefetcher to
the PCTable, as they didn't belong there. As such, they
have been renamed to remove the unnecessary prefix.
Change-Id: I3e54bc7dee65e1f78d96b0d548ac8345b7bd4364
Signed-off-by: Daniel <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/14358
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Return a pointer to the entry instead of returning a
boolean and passing a pointer reference. As a side
effect, change the name of the function to be more
descriptive of the functionality.
Change-Id: Iad44979e98031754c1d0857b1790c0eaf77e9765
Signed-off-by: Daniel <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/14356
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
