tests: There is no architecture called "timing".

I'm sure that's supposed to be "x86". By switching it over, the x86
regression tests became runnable again.

Change-Id: I9505703a0be71047ef3dd312ae83e76c2b32fdb5
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18568
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

misc: updated shabang for python script

The default python on MacOS doesn’t have an alias to python2.
The official python version supported in gem5 is Python2.7.

This patch updates the shabang according to the version required in gem5.

Change-Id: I9533c0f7858b5b3cab0ef101be1ee5cd718105b0
Reviewed-on: https://gem5-review.googlesource.com/c/15375
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

cpu: Replace the fastmem with a new CPU model

The AtomicSimpleCPU used to be able to access memory directly to speed
up simulation if no caches are used. This is fine as long as no
switching between CPU models is required. In order to switch to a new
CPU model that requires caches, we currently need to checkpoint the
system and restore it into a new configuration. The new
'atomic_noncaching' memory mode provides a solution that avoids this
issue since caches are bypassed in this mode. This changeset removes
the old fastmem option from the AtomicSimpleCPU and introduces a new
CPU, NonCachingSimpleCPU, which derives from the AtomicSimpleCPU.

The NonCachingSimpleCPU uses the same mechanism as the AtomicSimpleCPU
used to use when accessing memory in when fastmem was enabled.

This changeset also introduces a new switcheroo test that tests
switching between a NonCachingSimpleCPU and a TimingSimpleCPU with
caches.

Change-Id: If01893f9b37528b14f530c11ce6f53c097582c21
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/12419
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

tests: Add tests for DRAM low power modes

This patch adds two regression tests that execute the script in the
configs dir for triggering low power mode transitions. A separate
test is required for each page policy because for close-adaptive
page policy the DRAM goes into the Precharge Power-down mode while
for open-adaptive page policy it goes into the Activate Power-down
mode.

Change-Id: Iad61af23f132db046f2857cc3ef64b2bf42cf5e4
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5726
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

tests: Fix a typo for the default MI_example protocol

Change-Id: I1c88ba45e4fee3c254db06cac46045dfe6e68524
Signed-off-by: Sean Wilson <spwilson2@wisc.edu>
Reviewed-on: https://gem5-review.googlesource.com/3795
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

scons: Make MOESI_CMP_directory the default ARM ruby protocol

Previously ARM binaries were by default compiled with the MI_example
protocol. The MI_example protocol cannot properly support load/store
exclusive instructions and therefore it cannot be used to simulate
multicore ARM systems. This change changes to MOESI_CMP_directory as
the default ruby protocol for ARM systems.

Change-Id: I942d950ba466aea9a75f3d8764f9f3eddd0c3baa
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2906
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

misc: Update #!env calls for python to explicit version

In some newer Linux distributions, env python default to Python 3.0. This
patch explicitly uses "python2" instead of just "python" for all scripts
that use #!

Reported-by: Sanchayan Maity <maitysanchayan@gmail.com>
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>

tests: Add support for functional only tests

Modify the ClassicTest class to only emit a stat verification test
unit if there is a reference stat file. This makes it possible to
design tests that don't care about stat changes.

To generate purely functional tests, we need to be able to create
empty test reference directories. This does not work well with many
revision control systems. As a workaround, add a file named EMPTY to
the list of ignored files in the test harness. This file can be used
as a placeholder in otherwise empty test directories.

Change-Id: I583c8c4e55479f0d48fa99d0b0d1eac9221e6652
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>

tests: Add regex-based ignore rules for ref files

There are cases where we need to ignore files with specific extensions
(e.g., when Mercurial litters the file system with patch
rejects). Implement this functionality using a helper class
(FileIgnoreList) that supports both regular expressions and basic
string comparisons.

Change-Id: I34549754bd2e10ed230ffb2dc057403349f8fa78
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

tests: Split test results into running and verification

The test base class already assumes that test cases consists of a run
stage and a verification stage. Reflect this in the results class to
make it possible to detect cases where a run was successful, but
didn't verify.

Change-Id: I31ef393e496671221c5408aca41649cd8dda74ca
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>

tests: Only run Ruby tests when testing Ruby targets

Limit the test configs to Ruby-only configs when testing a Ruby target
that isn't MI_example. This avoids re-running configs that has already
been tested by the generic (non-Ruby) ISA target. This behavior was
the expected behavior prior to switching to the new test framework.

Change-Id: I3f138dbf9c7071ce862d1073aaec57c59afbc921
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>

tests: Fix incorrect stat.txt ignore when updating refs

ClassicTest was incorrectly ignoring stats.txt when updating reference
statistics. This was caused by ignore rules being applied too
aggressively when listing reference files. This changeset splits the
ignore rules into two different lists: 1) diff_ignore_files that lists
the files that shouldn't be diff:ed using the normal diff tool, and 2)
ref_ignore_files which lists files that should be ignored by the test
system.

Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>

tests: Add test infrastructure as a Python module

Implement gem5's test infrastructure as a Python module and a run
script that can be used without scons. The new implementation has
several features that were lacking from the previous test
infrastructure such as support for multiple output formats, automatic
runtime tracking, and better support for being run in a cluster
environment.

Tests consist of one or more steps (TestUnit). Units are run in two
stages, the first a run stage and then a verify stage. Units in the
verify stage are automatically skipped if any unit run stage wasn't
run. The library currently contains TestUnit implementations that run
gem5, diff stat files, and diff output files.

Existing tests are implemented by the ClassicTest class and "just
work". New tests can that don't rely on the old "run gem5 once and
diff output" strategy can be implemented by subclassing the Test base
class or ClassicTest.

Test results can be output in multiple formats. The module currently
supports JUnit, text (short and verbose), and Python's pickle
format. JUnit output allows CI systems to automatically get more
information about test failures. The pickled output contains all state
necessary to reconstruct a tests results object and is mainly intended
for the build system and CI systems.

Since many JUnit parsers parsers assume that test suite names look
like Java package names. We currently output path-like names with
slashes separating components. Test names are translated according to
these rules:

* '.' -> '-"
* '/' -> '.'

The test tool, tests.py, supports the following features:

* Test listing. Example: ./tests.py list arm/quick

* Running tests. Example:
./tests.py run -o output.pickle --format pickle \
../build/ARM/gem5.opt \
quick/se/00.hello/arm/linux/simple-timing

* Displaying pickled results. Example:
./tests.py show --format summary *.pickle

Change-Id: I527164bd791237aacfc65e7d7c0b67b695c5d17c
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Joel Hestness <jthestness@gmail.com>