summaryrefslogtreecommitdiff
path: root/src/mem/cache/compressors
AgeCommit message (Collapse)Author
2020-01-17mem-cache: Add more compression statsDaniel R. Carvalho
Add stats to calculate the total number of compressions, decompressions and the average compression size, in number of bits. Change-Id: I5eb563856c1ff54216e1edcd2886332b7481cbfe Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22609 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-11-28mem-cache: Avoid hiding a virtual method in the dictionary compressor.Gabe Black
The non-virtual version is later used in overrides of the virtual version whcih takes more arguments. Change-Id: I102d1185c7a616337c2a0429daa998706189292f Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23127 Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br> Maintainer: Gabe Black <gabeblack@google.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-11-28mem-cache: Remove a std::move clang says is unnecessary.Gabe Black
It also says it prevents an optimization. Change-Id: I9c21dc1a0c53cf70cefd1400564de07d1e845a75 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23124 Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br> Maintainer: Gabe Black <gabeblack@google.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-11-04mem-cache: Modify compressor to appease newer compilersDaniel R. Carvalho
The type of the local unique_ptr variable was different from the return type. In C++11 because of such difference, a copy-ellision would not be possible, and that required the use of a std::move. In C++14 the restriction of same types being required was removed, so std::move would not be needed anymore. With the addition of the -Wredundant-move warning in newer compilers, having the std::move on the return became an issue, breaking compilation. Change-Id: I45d18dfc500bb5db5fe360814feb91853c735a19 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22403 Tested-by: kokoro <noreply+kokoro@google.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-11-04mem-cache: Implement a perfect compressorDaniel R. Carvalho
Implement a perfect compressor that always manages to compresses data exactly to its maximum allowed compression ratio. This allows tracking a compression upper bound. Change-Id: Ibc68bf2dc84b75207795d5ba6304b9ed6dbeae8f Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21160 Tested-by: kokoro <noreply+kokoro@google.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
2019-11-04mem-cache: Make BDI a multi compressorDaniel R. Carvalho
BDI is a compressor containing multiple sub-compressors. Change-Id: I98411e2ef9dcc2182801a172dfc59ed7a8ee7dd4 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21159 Tested-by: kokoro <noreply+kokoro@google.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
2019-11-04mem-cache: Implement a multi compressorDaniel R. Carvalho
Implement a compressor that contains multiple sub-compressors and choses the one that provides the best compression results for each compression. Change-Id: I758cf67c84bd85edbea16b2a07b2068b00454461 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21158 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-11-04mem-cache: Implement BDI sub-compressorsDaniel R. Carvalho
Implement sub-compressors of BDI as public compressors so that they can be used separately. Change-Id: I710e35f39f4abb82fd02fd33b1b86a3f214c12cb Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21157 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu> Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
2019-11-04mem-cache: Implement a repeated values compressorDaniel R. Carvalho
The repeated values compressor can only compress data composed solely repeated instances of the same value. Change-Id: If2c4f47ad4af492d202ec2017e30ba52ee67e307 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21156 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu> Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
2019-11-04mem-cache: Implement a zero compressorDaniel R. Carvalho
The zero compressor can only compress data composed solely of zero bits. Change-Id: I8b359c03776a8748abd144a178bda944b5a1b766 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21155 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu> Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
2019-11-04mem-cache: Implement FPC-D cache compressionDaniel R. Carvalho
Implementation of Frequent Pattern Compression with limited Dictionary support (FPC-D) cache compressor, as described in "Opportunistic Compression for Direct-Mapped DRAM Caches", by Alameldeen et al. Change-Id: I26cc1646f95400b6a006f89754f6b2952f5b4aeb Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21154 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu> Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
2019-10-29mem-cache: Add a repeated value pattern to compressorsDaniel R. Carvalho
The repeated value pattern checks if values are composed of multiple instances of the same value. If successful, the bits of the repeated value are included only once in the compressed data. Change-Id: Ia7045b4e33a91fd8d712fe1ca689f7f8cb4e5feb Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21153 Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-10-29mem-cache: Inform unused bits instead of bytes in compressor patternDaniel R. Carvalho
Increase pattern precision by giving the number of unmatched bits instead of bytes. Change-Id: I5efbe9c31672cc973b4c89c741cdc8cc28d26285 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21152 Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-10-29mem-cache: Add a masked const value pattern to compressorsDaniel R. Carvalho
The masked pattern compares values to masked const non-dictionary values to determine whether these match. If successful, the bits that do not match must be added to the compressed data. Change-Id: I4c53568694dab916136fe384cb2ee10e554f7136 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21151 Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-10-29mem-cache: Add a masked pattern to compressorsDaniel R. Carvalho
The masked pattern compares masked values to masked dictionary entries to determine whether these values match. If successful, the bits that do not match must be added to the compressed data. Change-Id: I4b1c8feb0faa99576382b54a73a20c353f965d2a Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21150 Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-10-29mem-cache: Add an uncompressed pattern to compressorsDaniel R. Carvalho
The uncompressed pattern always stores the original data, and therefore it is always successful. All of the derived classes of the dictionary compressor must have this pattern as the last pattern of the pattern factory. Change-Id: I2a38fd56630d88ef8b918220dc4c2824a196a8a2 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21149 Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-10-29mem-cache: Templatize DictionaryCompressorDaniel R. Carvalho
Templatize DictionaryCompressor so that the dictionary entries' sizes can be changed. Change-Id: I3d89e3c692a721cefcd7e3c55d2ccdefa425f614 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21148 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-10-29mem-cache: Factor out CPack's dictionary functionalityDaniel R. Carvalho
Factor out dictionary functionality of CPack, so that it can be used easily for other compressors. As a side effect, create an addToDictionary function to allow subclasses to chose how to handle insertion. Change-Id: I02fae4e98b02db5a40467ec470b71020d5e867cb Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21147 Tested-by: kokoro <noreply+kokoro@google.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
2019-10-29mem-cache: Use shouldAllocate() instead of CPack's decompress()Daniel R. Carvalho
Split decompression functionality using the proper function to determine if a dictionary entry should be allocated after decompression or not. Change-Id: I4995304f4c4508c03c9fc1685f04511622969556 Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21146 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-10-29mem-cache: Limit compression sizeDaniel R. Carvalho
Add a threshold so that if the compressed size is greater than it, the compression is abandoned, and the data is considered uncompressible. Change-Id: Ic416195b06ec440a40263b75bd0f0383cde2ea6a Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21144 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-09-12mem-cache: Fix BDI size calculationDaniel R. Carvalho
The bitmask field indicates to which base a delta refers, and in the original paper it is fixed and proportional to the highest number of bases allowed in the compressed data. Change-Id: I271bf2e19e0765de52b933eaf6d4fcc2ce25d185 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19748 Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-07-17mem-cache: Create CPack compressorDaniel R. Carvalho
Implementation of C-Pack, as described in "C-Pack: A High- Performance Microprocessor Cache Compression Algorithm". C-Pack uses pattern matching schemes to detect and compress frequently appearing data patterns. As in the original paper, it divides the input in 32-bit words, and uses 6 patterns to match with its dictionary. For the patterns, each letter represents a byte: Z is a null byte, M is a dictionary match, X is a new value. The patterns are ZZZZ, XXXX, MMMM, MMXX, ZZZX, MMMX. Change-Id: I2efc9db2c862620dcc1155300e39be558f9017e0 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/11105 Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-05-08mem-cache: Add compression and decompression callsDaniel R. Carvalho
Add a compressor to the base cache class and compress within block allocation and decompress on writebacks. This change does not implement data expansion (fat writes) yet, nor it adds the compression latency to the block write time. Change-Id: Ie36db65f7487c9b05ec4aedebc2c7651b4cb4821 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/11410 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-05-08mem-cache: Create BDI CompressorDaniel R. Carvalho
Implement Base-Delta-Immediate compression, as described in 'Base-Delta-Immediate Compression: Practical Data Compression for On-Chip Caches' Change-Id: I7980c340ab53a086b748f4b2108de4adc775fac8 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/11412 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-05-08mem-cache: Add compression statsDaniel R. Carvalho
Add compression statistics to the compressors. It tracks the number of blocks that can fit into a certain power of two size, and the number of decompressions. For example, if a block is compressed to 100 bits, it will belong to the 128-bits compression size. Although it could also fit bigger sizes, they are not taken into account for the stats (i.e., the 100-bit compression will fit only the 128-bits size, not 256 or higher). We save stats for compressions that fail (i.e., compressed size is bigger than original cache line size). Change-Id: Idab71a40a660e33259908ccd880e42a880b5ee06 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/11103 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-05-08mem-cache: Create cache compressorDaniel R. Carvalho
Create basic template for cache compressors. A basic compressor must implement a compression and a decompression method. Change-Id: I83dc4d2b8d2bc5ed9f760c938edfa4ebdd6b8583 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/11100 Tested-by: kokoro <noreply+kokoro@google.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-02 05:17:34 +0000