config: add an option to list and select indirect branch predictor
Change-Id: I9a855d36de7d95b7785ff8a897899037cea6a3d8
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/15320
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
diff --git a/configs/common/BPConfig.py b/configs/common/BPConfig.py
index 65e6d65..e6fe1f9 100644
--- a/configs/common/BPConfig.py
+++ b/configs/common/BPConfig.py
@@ -86,3 +86,54 @@
for name, cls in inspect.getmembers(m5.objects, is_bp_class):
_bp_classes[name] = cls
+
+# The same for indirect branch predictors...
+# Dictionary of mapping names of real branch predictor models to classes.
+_indirect_bp_classes = {}
+
+
+def is_indirect_bp_class(cls):
+ """Determine if a class is an indirect 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.IndirectPredictor) and \
+ not cls.abstract
+ except (TypeError, AttributeError):
+ return False
+
+def get_indirect(name):
+ """Get an Indirect BP class from a user provided class name or alias."""
+
+ try:
+ indirect_bp_class = _indirect_bp_classes[name]
+ return indirect_bp_class
+ except KeyError:
+ print("%s is not a valid indirect BP model." % (name,))
+ sys.exit(1)
+
+def print_indirect_bp_list():
+ """Print a list of available indirect BP classes."""
+
+ print("Available Indirect BranchPredictor classes:")
+ doc_wrapper = TextWrapper(initial_indent="\t\t", subsequent_indent="\t\t")
+ for name, cls in _indirect_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 indirect_bp_names():
+ """Return a list of valid Indirect Branch Predictor names."""
+ return _indirect_bp_classes.keys()
+
+# Add all indirect BPs in the object hierarchy.
+for name, cls in inspect.getmembers(m5.objects, is_indirect_bp_class):
+ _indirect_bp_classes[name] = cls
+
diff --git a/configs/common/Options.py b/configs/common/Options.py
index e0d691f..4279b80 100644
--- a/configs/common/Options.py
+++ b/configs/common/Options.py
@@ -64,6 +64,10 @@
HWPConfig.print_hwp_list()
sys.exit(0)
+def _listIndirectBPTypes(option, opt, value, parser):
+ BPConfig.print_indirect_bp_list()
+ sys.exit(0)
+
def _listMemTypes(option, opt, value, parser):
MemConfig.print_mem_list()
sys.exit(0)
@@ -162,12 +166,19 @@
parser.add_option("--list-bp-types",
action="callback", callback=_listBPTypes,
help="List available branch predictor types")
+ parser.add_option("--list-indirect-bp-types",
+ action="callback", callback=_listIndirectBPTypes,
+ help="List available indirect 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("--indirect-bp-type", type="choice",
+ default="SimpleIndirectPredictor",
+ choices=BPConfig.indirect_bp_names(),
+ help = "type of indirect branch predictor to run with")
parser.add_option("--list-hwp-types",
action="callback", callback=_listHWPTypes,
help="List available hardware prefetcher types")
diff --git a/configs/common/Simulation.py b/configs/common/Simulation.py
index d1b623d..078ec0f 100644
--- a/configs/common/Simulation.py
+++ b/configs/common/Simulation.py
@@ -483,6 +483,11 @@
if options.bp_type:
bpClass = BPConfig.get(options.bp_type)
switch_cpus[i].branchPred = bpClass()
+ if options.indirect_bp_type:
+ IndirectBPClass = \
+ BPConfig.get_indirect(options.indirect_bp_type)
+ switch_cpus[i].branchPred.branchPred.indirectBranchPred = \
+ IndirectBPClass()
# If elastic tracing is enabled attach the elastic trace probe
# to the switch CPUs
diff --git a/configs/example/fs.py b/configs/example/fs.py
index bf6ae45..386421d 100644
--- a/configs/example/fs.py
+++ b/configs/example/fs.py
@@ -206,6 +206,11 @@
if options.bp_type:
bpClass = BPConfig.get(options.bp_type)
test_sys.cpu[i].branchPred = bpClass()
+ if options.indirect_bp_type:
+ IndirectBPClass = \
+ BPConfig.get_indirect(options.indirect_bp_type)
+ test_sys.cpu[i].branchPred.indirectBranchPred = \
+ IndirectBPClass()
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 4ee0390..cbebcea 100644
--- a/configs/example/se.py
+++ b/configs/example/se.py
@@ -240,6 +240,10 @@
bpClass = BPConfig.get(options.bp_type)
system.cpu[i].branchPred = bpClass()
+ if options.indirect_bp_type:
+ indirectBPClass = BPConfig.get_indirect(options.indirect_bp_type)
+ system.cpu[i].branchPred.indirectBranchPred = indirectBPClass()
+
system.cpu[i].createThreads()
system.redirect_paths = redirect_paths(os.path.expanduser(options.chroot))
