configs: Added an option for choosing branch predictor type
Added the parameter "--bp-type" to set the branch predictor type
Added the parameter "--list-bp-types" to list all the available branch
predictor types
Change-Id: Ia6aae90c784aef359b6d8233c8383cd7a871aca1
Signed-off-by: Pau Cabre <pau.cabre@metempsy.com>
Reviewed-on: https://gem5-review.googlesource.com/c/14015
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
diff --git a/configs/common/BPConfig.py b/configs/common/BPConfig.py
new file mode 100644
index 0000000..5e5b92f
--- /dev/null
+++ b/configs/common/BPConfig.py
@@ -0,0 +1,87 @@
+# Copyright (c) 2018 Metempsy Technology Consulting
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Pau Cabre
+
+# This file is a copy of MemConfig.py / CpuConfig.py, but modified to
+# hanle branch predictors instead of memory controllers / CPUs
+
+from __future__ import print_function
+
+from m5 import fatal
+import m5.objects
+import inspect
+import sys
+from textwrap import TextWrapper
+
+# Dictionary of mapping names of real branch predictor models to classes.
+_bp_classes = {}
+
+
+def is_bp_class(cls):
+ """Determine if a class is a branch predictor that can be instantiated"""
+
+ # We can't use the normal inspect.isclass because the ParamFactory
+ # and ProxyFactory classes have a tendency to confuse it.
+ try:
+ return issubclass(cls, m5.objects.BranchPredictor) and \
+ not cls.abstract
+ except (TypeError, AttributeError):
+ return False
+
+def get(name):
+ """Get a BP class from a user provided class name or alias."""
+
+ try:
+ bp_class = _bp_classes[name]
+ return bp_class
+ except KeyError:
+ print("%s is not a valid BP model." % (name,))
+ sys.exit(1)
+
+def print_bp_list():
+ """Print a list of available BP classes."""
+
+ print("Available BranchPredictor classes:")
+ doc_wrapper = TextWrapper(initial_indent="\t\t", subsequent_indent="\t\t")
+ for name, cls in _bp_classes.items():
+ print("\t%s" % name)
+
+ # Try to extract the class documentation from the class help
+ # string.
+ doc = inspect.getdoc(cls)
+ if doc:
+ for line in doc_wrapper.wrap(doc):
+ print(line)
+
+def bp_names():
+ """Return a list of valid Branch Predictor names."""
+ return _bp_classes.keys()
+
+# Add all BPs in the object hierarchy.
+for name, cls in inspect.getmembers(m5.objects, is_bp_class):
+ _bp_classes[name] = cls
+
diff --git a/configs/common/Options.py b/configs/common/Options.py
index c36dc38..536da44 100644
--- a/configs/common/Options.py
+++ b/configs/common/Options.py
@@ -44,6 +44,7 @@
from common.Benchmarks import *
from common import CpuConfig
+from common import BPConfig
from common import MemConfig
from common import PlatformConfig
@@ -51,6 +52,10 @@
CpuConfig.print_cpu_list()
sys.exit(0)
+def _listBPTypes(option, opt, value, parser):
+ BPConfig.print_bp_list()
+ sys.exit(0)
+
def _listMemTypes(option, opt, value, parser):
MemConfig.print_mem_list()
sys.exit(0)
@@ -146,6 +151,15 @@
parser.add_option("--cpu-type", type="choice", default="AtomicSimpleCPU",
choices=CpuConfig.cpu_names(),
help = "type of cpu to run with")
+ parser.add_option("--list-bp-types",
+ action="callback", callback=_listBPTypes,
+ help="List available branch predictor types")
+ parser.add_option("--bp-type", type="choice", default=None,
+ choices=BPConfig.bp_names(),
+ help = """
+ type of branch predictor to run with
+ (if not set, use the default branch predictor of
+ the selected CPU)""")
parser.add_option("--checker", action="store_true");
parser.add_option("--cpu-clock", action="store", type="string",
default='2GHz',
diff --git a/configs/common/Simulation.py b/configs/common/Simulation.py
index 23a7783..19bd962 100644
--- a/configs/common/Simulation.py
+++ b/configs/common/Simulation.py
@@ -46,6 +46,7 @@
from os.path import join as joinpath
from common import CpuConfig
+from common import BPConfig
from common import MemConfig
import m5
@@ -478,6 +479,9 @@
# Add checker cpu if selected
if options.checker:
switch_cpus[i].addCheckerCpu()
+ if options.bp_type:
+ bpClass = BPConfig.get(options.bp_type)
+ switch_cpus[i].branchPred = bpClass()
# If elastic tracing is enabled attach the elastic trace probe
# to the switch CPUs
diff --git a/configs/common/cores/arm/HPI.py b/configs/common/cores/arm/HPI.py
index a6f77af..2efb7df 100644
--- a/configs/common/cores/arm/HPI.py
+++ b/configs/common/cores/arm/HPI.py
@@ -1443,7 +1443,7 @@
enableIdling = True
- branchPred = HPI_BP(numThreads = Parent.numThreads)
+ branchPred = HPI_BP()
itb = HPI_ITB()
dtb = HPI_DTB()
diff --git a/configs/example/fs.py b/configs/example/fs.py
index 3997ed7..3fdf151 100644
--- a/configs/example/fs.py
+++ b/configs/example/fs.py
@@ -63,6 +63,7 @@
from common import CacheConfig
from common import MemConfig
from common import CpuConfig
+from common import BPConfig
from common.Caches import *
from common import Options
@@ -199,6 +200,9 @@
test_sys.cpu[i].addSimPointProbe(options.simpoint_interval)
if options.checker:
test_sys.cpu[i].addCheckerCpu()
+ if options.bp_type:
+ bpClass = BPConfig.get(options.bp_type)
+ test_sys.cpu[i].branchPred = bpClass()
test_sys.cpu[i].createThreads()
# If elastic tracing is enabled when not restoring from checkpoint and
diff --git a/configs/example/se.py b/configs/example/se.py
index f12d4a9..8403066 100644
--- a/configs/example/se.py
+++ b/configs/example/se.py
@@ -61,6 +61,7 @@
from common import Simulation
from common import CacheConfig
from common import CpuConfig
+from common import BPConfig
from common import MemConfig
from common.Caches import *
from common.cpu2000 import *
@@ -233,6 +234,10 @@
if options.checker:
system.cpu[i].addCheckerCpu()
+ if options.bp_type:
+ bpClass = BPConfig.get(options.bp_type)
+ system.cpu[i].branchPred = bpClass()
+
system.cpu[i].createThreads()
if options.ruby:
diff --git a/src/cpu/pred/BranchPredictor.py b/src/cpu/pred/BranchPredictor.py
index 9f35165..1eeecde 100644
--- a/src/cpu/pred/BranchPredictor.py
+++ b/src/cpu/pred/BranchPredictor.py
@@ -29,6 +29,7 @@
from m5.SimObject import SimObject
from m5.params import *
+from m5.proxy import *
class BranchPredictor(SimObject):
type = 'BranchPredictor'
@@ -36,7 +37,7 @@
cxx_header = "cpu/pred/bpred_unit.hh"
abstract = True
- numThreads = Param.Unsigned(1, "Number of threads")
+ numThreads = Param.Unsigned(Parent.numThreads, "Number of threads")
BTBEntries = Param.Unsigned(4096, "Number of BTB entries")
BTBTagSize = Param.Unsigned(16, "Size of the BTB tags, in bits")
RASSize = Param.Unsigned(16, "RAS size")
