[gem5-dev] Change in gem5/gem5[master]: cpu: Added 8KB and 64KB TAGE-SC-L branch predictor
Pau Cabre has submitted this change and it was merged. (
https://gem5-review.googlesource.com/c/public/gem5/+/14855 )
Change subject: cpu: Added 8KB and 64KB TAGE-SC-L branch predictor
..
cpu: Added 8KB and 64KB TAGE-SC-L branch predictor
The original paper of the branch predictor can be found here:
http://www.jilp.org/cbp2016/paper/AndreSeznecLimited.pdf
Change-Id: I684863752407685adaacedebb699205c3559c528
Reviewed-on: https://gem5-review.googlesource.com/c/14855
Reviewed-by: Sudhanshu Jha
Reviewed-by: Andreas Sandberg
Maintainer: Andreas Sandberg
---
M src/cpu/pred/BranchPredictor.py
M src/cpu/pred/SConscript
M src/cpu/pred/loop_predictor.cc
M src/cpu/pred/loop_predictor.hh
M src/cpu/pred/ltage.cc
M src/cpu/pred/ltage.hh
A src/cpu/pred/statistical_corrector.cc
A src/cpu/pred/statistical_corrector.hh
M src/cpu/pred/tage.cc
M src/cpu/pred/tage.hh
M src/cpu/pred/tage_base.cc
M src/cpu/pred/tage_base.hh
A src/cpu/pred/tage_sc_l.cc
A src/cpu/pred/tage_sc_l.hh
A src/cpu/pred/tage_sc_l_64KB.cc
A src/cpu/pred/tage_sc_l_64KB.hh
A src/cpu/pred/tage_sc_l_8KB.cc
A src/cpu/pred/tage_sc_l_8KB.hh
18 files changed, 2,541 insertions(+), 56 deletions(-)
Approvals:
Andreas Sandberg: Looks good to me, approved; Looks good to me, approved
Sudhanshu Jha: Looks good to me, approved
diff --git a/src/cpu/pred/BranchPredictor.py
b/src/cpu/pred/BranchPredictor.py
index 1d5fd5e..85b225c 100644
--- a/src/cpu/pred/BranchPredictor.py
+++ b/src/cpu/pred/BranchPredictor.py
@@ -118,7 +118,7 @@
logUResetPeriod = Param.Unsigned(18,
"Log period in number of branches to reset TAGE useful counters")
numUseAltOnNa = Param.Unsigned(1, "Number of USE_ALT_ON_NA counters")
-useAltOnNaBits = Param.Unsigned(4, "Size of the USE_ALT_ON_NA counter")
+useAltOnNaBits = Param.Unsigned(4, "Size of the USE_ALT_ON_NA
counter(s)")
maxNumAlloc = Param.Unsigned(1,
"Max number of TAGE entries allocted on mispredict")
@@ -185,6 +185,96 @@
optionalAgeReset = Param.Bool(True,
"Reset age bits optionally in some cases")
+class TAGE_SC_L_TAGE(TAGEBase):
+type = 'TAGE_SC_L_TAGE'
+cxx_class = 'TAGE_SC_L_TAGE'
+cxx_header = "cpu/pred/tage_sc_l.hh"
+abstract = True
+tagTableTagWidths = [0]
+numUseAltOnNa = 16
+pathHistBits = 27
+maxNumAlloc = 2
+logUResetPeriod = 10
+useAltOnNaBits = 5
+# TODO No speculation implemented as of now
+speculativeHistUpdate = False
+
+# This size does not set the final sizes of the tables (it is just used
+# for some calculations)
+# Instead, the number of TAGE entries comes from shortTagsTageEntries
and
+# longTagsTageEntries
+logTagTableSize = Param.Unsigned("Log size of each tag table")
+
+shortTagsTageFactor = Param.Unsigned(
+"Factor for calculating the total number of short tags TAGE
entries")
+
+longTagsTageFactor = Param.Unsigned(
+"Factor for calculating the total number of long tags TAGE
entries")
+
+shortTagsSize = Param.Unsigned(8, "Size of the short tags")
+
+longTagsSize = Param.Unsigned("Size of the long tags")
+
+firstLongTagTable = Param.Unsigned("First table with long tags")
+
+truncatePathHist = Param.Bool(True,
+"Truncate the path history to its configured size")
+
+
+class TAGE_SC_L_TAGE_64KB(TAGE_SC_L_TAGE):
+type = 'TAGE_SC_L_TAGE_64KB'
+cxx_class = 'TAGE_SC_L_TAGE_64KB'
+cxx_header = "cpu/pred/tage_sc_l_64KB.hh"
+nHistoryTables = 36
+
+minHist = 6
+maxHist = 3000
+
+tagTableUBits = 1
+
+logTagTableSizes = [13]
+
+# This is used to handle the 2-way associativity
+# (all odd entries are set to one, and if the corresponding even entry
+# is set to one, then there is a 2-way associativity for this pair)
+# Entry 0 is for the bimodal and it is ignored
+# Note: For this implementation, some odd entries are also set to 0 to
save
+# some bits
+noSkip = [0,0,1,0,0,0,1,0,0,1,1,1,1,1,1,1,1,1,1,
+1,1,1,1,0,1,0,1,0,1,0,0,0,1,0,0,0,1]
+
+logTagTableSize = 10
+shortTagsTageFactor = 10
+longTagsTageFactor = 20
+
+longTagsSize = 12
+
+firstLongTagTable = 13
+
+class TAGE_SC_L_TAGE_8KB(TAGE_SC_L_TAGE):
+type = 'TAGE_SC_L_TAGE_8KB'
+cxx_class = 'TAGE_SC_L_TAGE_8KB'
+cxx_header = "cpu/pred/tage_sc_l_8KB.hh"
+
+nHistoryTables = 30
+
+minHist = 4
+maxHist = 1000
+
+logTagTableSize = 7
+shortTagsTageFactor = 9
+longTagsTageFactor = 17
+longTagsSize = 12
+
+logTagTableSizes = [12]
+
+firstLongTagTable = 11
+
+truncatePathHist = False
+
+noSkip =
[0,0,1,0,1,0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,0,1,0,1,0,1,0,1]
+
+tagTableUBits = 2
# LTAGE branch predictor as described in
# https://www.irisa.fr/caps/people/seznec/L-TAGE.pdf
@@ -196,4 +286,177 @@
cxx_header = "cpu/pred/ltage.hh"
tage = LTAGE_TAGE()
+
[gem5-dev] Change in gem5/gem5[master]: cpu: Added 8KB and 64KB TAGE-SC-L branch predictor
Hello Javier Bueno Hedo, Sudhanshu Jha, Andreas Sandberg, I'd like you to reexamine a change. Please visit https://gem5-review.googlesource.com/c/public/gem5/+/14855 to look at the new patch set (#16). Change subject: cpu: Added 8KB and 64KB TAGE-SC-L branch predictor .. cpu: Added 8KB and 64KB TAGE-SC-L branch predictor The original paper of the branch predictor can be found here: http://www.jilp.org/cbp2016/paper/AndreSeznecLimited.pdf Change-Id: I684863752407685adaacedebb699205c3559c528 --- M src/cpu/pred/BranchPredictor.py M src/cpu/pred/SConscript M src/cpu/pred/loop_predictor.cc M src/cpu/pred/loop_predictor.hh M src/cpu/pred/ltage.cc M src/cpu/pred/ltage.hh A src/cpu/pred/statistical_corrector.cc A src/cpu/pred/statistical_corrector.hh M src/cpu/pred/tage.cc M src/cpu/pred/tage.hh M src/cpu/pred/tage_base.cc M src/cpu/pred/tage_base.hh A src/cpu/pred/tage_sc_l.cc A src/cpu/pred/tage_sc_l.hh A src/cpu/pred/tage_sc_l_64KB.cc A src/cpu/pred/tage_sc_l_64KB.hh A src/cpu/pred/tage_sc_l_8KB.cc A src/cpu/pred/tage_sc_l_8KB.hh 18 files changed, 2,541 insertions(+), 56 deletions(-) -- To view, visit https://gem5-review.googlesource.com/c/public/gem5/+/14855 To unsubscribe, or for help writing mail filters, visit https://gem5-review.googlesource.com/settings Gerrit-Project: public/gem5 Gerrit-Branch: master Gerrit-Change-Id: I684863752407685adaacedebb699205c3559c528 Gerrit-Change-Number: 14855 Gerrit-PatchSet: 16 Gerrit-Owner: Pau Cabre Gerrit-Assignee: Ilias Vougioukas Gerrit-Reviewer: Andreas Sandberg Gerrit-Reviewer: Javier Bueno Hedo Gerrit-Reviewer: Pau Cabre Gerrit-Reviewer: Sudhanshu Jha Gerrit-CC: Ilias Vougioukas Gerrit-MessageType: newpatchset ___ gem5-dev mailing list gem5-dev@gem5.org http://m5sim.org/mailman/listinfo/gem5-dev
[gem5-dev] Change in gem5/gem5[master]: cpu: Added 8KB and 64KB TAGE-SC-L branch predictor
Hello Javier Bueno Hedo, Sudhanshu Jha, I'd like you to reexamine a change. Please visit https://gem5-review.googlesource.com/c/public/gem5/+/14855 to look at the new patch set (#15). Change subject: cpu: Added 8KB and 64KB TAGE-SC-L branch predictor .. cpu: Added 8KB and 64KB TAGE-SC-L branch predictor The original paper of the branch predictor can be found here: http://www.jilp.org/cbp2016/paper/AndreSeznecLimited.pdf Change-Id: I684863752407685adaacedebb699205c3559c528 --- M src/cpu/pred/BranchPredictor.py M src/cpu/pred/SConscript M src/cpu/pred/loop_predictor.cc M src/cpu/pred/loop_predictor.hh M src/cpu/pred/ltage.cc M src/cpu/pred/ltage.hh A src/cpu/pred/statistical_corrector.cc A src/cpu/pred/statistical_corrector.hh M src/cpu/pred/tage.cc M src/cpu/pred/tage.hh M src/cpu/pred/tage_base.cc M src/cpu/pred/tage_base.hh A src/cpu/pred/tage_sc_l.cc A src/cpu/pred/tage_sc_l.hh A src/cpu/pred/tage_sc_l_64KB.cc A src/cpu/pred/tage_sc_l_64KB.hh A src/cpu/pred/tage_sc_l_8KB.cc A src/cpu/pred/tage_sc_l_8KB.hh 18 files changed, 2,544 insertions(+), 56 deletions(-) -- To view, visit https://gem5-review.googlesource.com/c/public/gem5/+/14855 To unsubscribe, or for help writing mail filters, visit https://gem5-review.googlesource.com/settings Gerrit-Project: public/gem5 Gerrit-Branch: master Gerrit-Change-Id: I684863752407685adaacedebb699205c3559c528 Gerrit-Change-Number: 14855 Gerrit-PatchSet: 15 Gerrit-Owner: Pau Cabre Gerrit-Assignee: Ilias Vougioukas Gerrit-Reviewer: Javier Bueno Hedo Gerrit-Reviewer: Pau Cabre Gerrit-Reviewer: Sudhanshu Jha Gerrit-CC: Andreas Sandberg Gerrit-CC: Ilias Vougioukas Gerrit-MessageType: newpatchset ___ gem5-dev mailing list gem5-dev@gem5.org http://m5sim.org/mailman/listinfo/gem5-dev
[gem5-dev] Change in gem5/gem5[master]: cpu: Added 8KB and 64KB TAGE-SC-L branch predictor
Pau Cabre has uploaded a new patch set (#9). ( https://gem5-review.googlesource.com/c/public/gem5/+/14855 ) Change subject: cpu: Added 8KB and 64KB TAGE-SC-L branch predictor .. cpu: Added 8KB and 64KB TAGE-SC-L branch predictor The original paper of the branch predictor can be found here: http://www.jilp.org/cbp2016/paper/AndreSeznecLimited.pdf And this is the original implementation: http://www.jilp.org/cbp2016/code/AndreSeznecLimited.tar.gz Change-Id: I684863752407685adaacedebb699205c3559c528 Signed-off-by: Pau Cabre --- M src/cpu/pred/2bit_local.cc M src/cpu/pred/2bit_local.hh M src/cpu/pred/BranchPredictor.py M src/cpu/pred/SConscript M src/cpu/pred/bi_mode.cc M src/cpu/pred/bi_mode.hh M src/cpu/pred/bpred_unit.cc M src/cpu/pred/bpred_unit.hh M src/cpu/pred/ltage.cc M src/cpu/pred/ltage.hh M src/cpu/pred/tage.cc M src/cpu/pred/tage.hh A src/cpu/pred/tage_sc_l.cc A src/cpu/pred/tage_sc_l.hh A src/cpu/pred/tage_sc_l_64KB.cc A src/cpu/pred/tage_sc_l_64KB.hh A src/cpu/pred/tage_sc_l_8KB.cc A src/cpu/pred/tage_sc_l_8KB.hh M src/cpu/pred/tournament.cc M src/cpu/pred/tournament.hh 20 files changed, 2,605 insertions(+), 186 deletions(-) -- To view, visit https://gem5-review.googlesource.com/c/public/gem5/+/14855 To unsubscribe, or for help writing mail filters, visit https://gem5-review.googlesource.com/settings Gerrit-Project: public/gem5 Gerrit-Branch: master Gerrit-Change-Id: I684863752407685adaacedebb699205c3559c528 Gerrit-Change-Number: 14855 Gerrit-PatchSet: 9 Gerrit-Owner: Pau Cabre Gerrit-Assignee: Ilias Vougioukas Gerrit-Reviewer: Pau Cabre Gerrit-CC: Ilias Vougioukas Gerrit-MessageType: newpatchset ___ gem5-dev mailing list gem5-dev@gem5.org http://m5sim.org/mailman/listinfo/gem5-dev
