[dvsim] Make build-randomization opt-in
THis commit changes the dvsim infra from the original implementation
of always enabling build randomization by default, to opt-in.
The build-randomization is now enabled only if the user passes
--build-seed <optional-seed>` explicitly on the command-line. This
enables the users to properly reproduce failures.
It also enables modification of in-tree sources via pre-build commands
that can modify random constant packages. The previous implementation
made it difficult to achieve reproduction of these mutated sources.
It also did not factor in the case where a design could have multiple
build-modes in effect (default, cover_reg_top, etc).
All build-time source modifications are now to be wrapped in `build_seed`
mode, which is a simulation mode that is strictly enabled on the
command-line. The nightly regressions run at Google will eventually
be updated to pass on this switch as well.
If the --build-seed switch is not passed, no build randomization is
performed - the staticly checked-in sources are used as-is. The BUILD_SEED
which was updated in the previous implementation on every invocation
is also now fixed to 1 in this scenario.
Signed-off-by: Srikrishna Iyer <sriyer@google.com>
diff --git a/util/dvsim/Deploy.py b/util/dvsim/Deploy.py
index 0318b95..ae003db 100644
--- a/util/dvsim/Deploy.py
+++ b/util/dvsim/Deploy.py
@@ -296,13 +296,9 @@
cmds_list_vars = ["pre_build_cmds", "post_build_cmds"]
weight = 5
- # A static, randomized seed that is fixed across all builds.
- # This value can be overridden by --build-seed switch.
- seed = random.getrandbits(32)
-
def __init__(self, build_mode, sim_cfg):
self.build_mode_obj = build_mode
- self.seed = CompileSim.seed
+ self.seed = sim_cfg.build_seed
super().__init__(sim_cfg)
def _define_attrs(self):
@@ -356,13 +352,8 @@
target = "build"
- # A static, randomized seed that is fixed across all builds.
- # This value can be overridden by --build-seed switch.
- seed = random.getrandbits(32)
-
def __init__(self, build_mode, sim_cfg):
self.build_mode_obj = build_mode
- self.seed = CompileOneShot.seed
super().__init__(sim_cfg)
def _define_attrs(self):
diff --git a/util/dvsim/SimCfg.py b/util/dvsim/SimCfg.py
index 843feb1..9394df0 100644
--- a/util/dvsim/SimCfg.py
+++ b/util/dvsim/SimCfg.py
@@ -74,6 +74,7 @@
self.en_run_modes = []
self.en_run_modes.extend(args.run_modes)
self.build_unique = args.build_unique
+ self.build_seed = args.build_seed
self.build_only = args.build_only
self.run_only = args.run_only
self.reseed_ovrd = args.reseed
@@ -105,6 +106,8 @@
self.en_build_modes.append("profile")
if self.xprop_off is not True:
self.en_build_modes.append("xprop")
+ if self.build_seed:
+ self.en_build_modes.append("build_seed")
# Options built from cfg_file files
self.project = ""
@@ -619,8 +622,9 @@
results_str += f"### Simulator: {self.tool.upper()}\n"
# Print the build seed used for clarity.
- if not self.run_only:
- results_str += f"### Build seed: {CompileSim.seed}\n"
+ if self.build_seed and not self.run_only:
+ results_str += ("### Build randomization enabled with "
+ f"--build-seed {self.build_seed}\n")
if not results.table:
results_str += "No results to display.\n"
diff --git a/util/dvsim/dvsim.py b/util/dvsim/dvsim.py
index 16a748d..bf2bb69 100755
--- a/util/dvsim/dvsim.py
+++ b/util/dvsim/dvsim.py
@@ -23,6 +23,7 @@
import datetime
import logging as log
import os
+import random
import shlex
import subprocess
import sys
@@ -33,7 +34,7 @@
import LauncherFactory
import LocalLauncher
from CfgFactory import make_cfg
-from Deploy import CompileOneShot, CompileSim, RunTest
+from Deploy import RunTest
from Timer import Timer
from utils import (TS_FORMAT, TS_FORMAT_LONG, VERBOSE, rm_path,
run_cmd_with_timeout)
@@ -474,9 +475,13 @@
seedg = parser.add_argument_group('Build / test seeds')
seedg.add_argument("--build-seed",
+ nargs="?",
type=int,
+ const=random.getrandbits(32),
metavar="S",
- help=('Seed used for compile-time randomization.'))
+ help=('Randomize the build. Uses the seed value passed '
+ 'an additional argument, else it randomly picks '
+ 'a 32-bit unsigned integer.'))
seedg.add_argument("--seeds",
"-s",
@@ -656,10 +661,7 @@
setattr(args, "timestamp_long", curr_ts.strftime(TS_FORMAT_LONG))
setattr(args, "timestamp", curr_ts.strftime(TS_FORMAT))
- # Register the seeds from command line with Compile* / RunTest classes.
- if args.build_seed:
- CompileSim.seed = args.build_seed
- CompileOneShot.seed = args.build_seed
+ # Register the seeds from command line with the RunTest class.
RunTest.seeds = args.seeds
# If we are fixing a seed value, no point in tests having multiple reseeds.
