This patch removes support for the two instructions above from the GNU
simulator, including the corresponding tests. These instructions do
not really exist in BPF and are not recognized as such by the kernel
verifier. This has now been pointed out during the standardization of
the BPF ISA.
Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
This commit is the result of the following actions:
- Running gdb/copyright.py to update all of the copyright headers to
include 2024,
- Manually updating a few files the copyright.py script told me to
update, these files had copyright headers embedded within the
file,
- Regenerating gdbsupport/Makefile.in to refresh it's copyright
date,
- Using grep to find other files that still mentioned 2023. If
these files were updated last year from 2022 to 2023 then I've
updated them this year to 2024.
I'm sure I've probably missed some dates. Feel free to fix them up as
you spot them.
The BPF virtual machine does not support neg instructions operating on
immediates, and these erroneous instructions were recently removed from
gas. Remove them from the simulator as well.
This patch fixes the semantics of the neg and neg32 BPF instructions
in the simulator, and also updates the corresponding tests
accordingly.
Tested in target bpf-unknown-none.
The BPF port in binutils has been rewritten (commit
d218e7fedc) in order to not be longer
based on CGEN. Please see that commit log for more information.
This patch updates the BPF simulator accordingly. The new
implementation is much simpler and it is based on the new BPF opcodes.
Tested with target bpf-unknown-none with both 64-bit little-endian
host and 32-bit little-endian host.
Note that I have not tested in a big-endian host yet. I will do so
once this lands upstream so I can use the GCC compiler farm.
Add explicit arch-specific modules.c rules to keep the build from
generating an incorrect common/modules.c. Otherwise the pattern
rules would cascade such that it'd look for $arch/modules.o which
turned into common/modules.c which triggered the gen rule.
My local testing of this code didn't catch this bug because of how
Automake manages .Po (dependency files) in incremental builds -- it
was adding extra rules that override the pattern rules which caused
the build to generate correct modules.c files. But when building
from a cold cache, the pattern rules would force common/modules.c to
be used leading to crashes at runtime.
This makes sure the arch-specific modules.c wildcard is matched and
not the common/%.c so that we compile it correctly. It also makes
sure each subdir has depdir logic enabled.
Now that we build these objects in the top dir & generate modules.c
there, we don't need to generate them all first -- we can let the
normal dependency graph take care of building things in parallel.
This simplifies the build logic and avoids an Automake bug where the
common_libcommon_a_OBJECTS variable isn't set in the arch libsim.a
DEPENDENCIES for targets that, alphabetically, come before "common".
We aren't affected by that bug with the current code, but as we move
things out of SIM_ALL_RECURSIVE_DEPS and rely on finer dependencies,
we will trip over it.
The objects are still compiled in the subdir, but the creation of the
archive itself is in the top-level. This is a required step before we
can move compilation itself up, and makes it easier to review.
The downside is that each object compile is a recursive make instead of
a single one. On my 4 core system, it adds ~100msec to the build per
port, so it's not great, but it shouldn't be a big deal. This will go
away of course once the top-level compiles objects.
Add rules for tracking generated subdir modules.c files. This doesn't
actually generate the file from the top-level, but allows us to add
rules that need to be ordered wrt it. Once those changes land, we can
rework this to actually generate from the top-level.
This currently builds off of the objects that go into the libsim.a as
we don't build those from the top-level either. Once we migrate that
up, we can switch this to the source files directly. It's a bit hacky
overall, but makes it easier to migrate things in smaller chunks, and
we aren't going to keep this logic long term.
Automake's automatic header deptracking has a bootstrap problem where
it can't detect generated headers when compiling. We've been handling
that by adding a custom SIM_ALL_RECURSIVE_DEPS variable, but that only
works when building objects recursively in subdirs. As we move those
out to the top-level, we don't have any recursive steps anymore. The
Automake approach is to declare those headers in BUILT_SOURCES.
This isn't completely foolproof as the Automake manual documents: it
only activates for `make all`, not `make foo.o`, but that shouldn't be
a huge limitation as it only affects the initial compile. After that,
rebuilds should work fine.
Clean up includes a bit by making ports include opcodes/ headers
explicitly. This matches other projects, and makes it more clear
where these headers are coming from.
This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
All the runtimes were only initializing a single CPU. When SMP is
enabled, things quickly crash as none of the other CPU structs are
setup. Change the default from 0 to the compile time value.
The cgen-types.h header sets up types that are needed by cgen-defs.h,
so move the include out of sim-main.h and to that header. It might
be needed in other specific modules, but for now let's kick it out of
sim-main.h to make some progress. Things still build with just this.
Since SIM_ADDR is always 32-bit, it might truncate the address with
64-bit ELFs. Since we load that addr from the bfd, use the bfd_vma
type which matches the bfd_get_start_address API.
We've been using this only to set the default word size to 64. We
can easily move this into the makefile via a -D compiler flag and
clean up the build logic quite a bit.
Automake will run each subdir individually before moving on to the next
one. This means that the linking phase, a single threaded process, will
not run in parallel with anything else. When we have to link ~32 ports,
that's 32 link steps that don't take advantage of parallel systems. On
my really old 4-core system, this cuts a multi-target build from ~60 sec
to ~30 sec. We eventually want to move all compile+link steps to this
common dir anyways, so might as well move linking now for a nice speedup.
We use noinst_PROGRAMS instead of bin_PROGRAMS because we're taking care
of the install ourselves rather than letting automake process it.
These manual settings were necessary when we weren't doing automatic
header dependency tracking. That was changed a while ago, and we use
automake now to do it all for us. As a result, many of these vars
aren't even referenced anymore.
Further, some of the source file generation (e.g. .c files, or igen,
or cgen outputs) were moved to the common automake build, and it takes
care of dependency tracking for us with the object files.
When reading/writing arbitrary data to the system's memory, the unsigned
char pointer type doesn't make that much sense. Switch it to void so we
align a bit with standard C library read/write functions, and to avoid
having to sprinkle casts everywhere.
This was left in subdirs because of the dynamic cgen usage. However,
we can move this breakpoint call to runtime and let gdb detect whether
the symbol exists.
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.
For the avoidance of doubt, all changes in this commits were
performed by the script.
The ## marker tells automake to not include the comment in its
generated output, so use that in most places where the comment
only makes sense in the inputs.
We've been passing the environment strings to sim_create_inferior,
but most ports don't do anything with them. A few will use ad-hoc
logic to stuff the stack for user-mode programs, but that's it.
Let's formalize this across the board by storing the strings in the
normal sim state. This will allow (in future commits) supporting
more functionality in the run interface, and to unify some of the
libgloss syscalls.
We use the program argv to both find the program to run (argv[0]) and
to hold the arguments to the program. Most of the time this is fine,
but if we want to let programs specify argv[0] independently (which is
possible in standard *NIX programs), this double duty doesn't work.
So let's split the path to the program to run out into a separate
field by itself. This simplifies the various sim_open funcs too.
By itself, this code is more of a logical cleanup than something that
is super useful. But it will open up customization of argv[0] in a
follow up commit. Split the changes to make it easier to review.
These rules don't depend on the target compiler settings, so hoist
the build logic up to the common builds for better parallelization.
We have to extend the genmloop.sh logic a bit to allow outputting
to a subdir since it always assumed cwd was the right place.
We leave the cgen maintainer rules in the subdirs for now as they
aren't normally run, and they rely on cgen logic that has not yet
been generalized.
Now that ChangeLog entries are no longer used for sim patches,
this commit renames all relevant sim ChangeLog to ChangeLog-2021,
similar to what we would do in the context of the "Start of New
Year" procedure.
The purpose of this change is to avoid people merging ChangeLog
entries by mistake when applying existing commits that they are
currently working on.
Also throw in a .gitignore entry to keep people from adding new
ChangeLog files anywhere in the sim tree.
Move these options up to the common dir so we only test & export
them once across all ports.
The setting only affects igen based ports, and they were turning
this on by default, so keep the default in place.
The cgen scache module is enabled by every cgen port, and with the
same default value of 16k (which matches the common default value).
Let's pull this option out of the individual ports (via CPPFLAGS)
and into the common code (via config.h).
The object itself is compiled only for cgen ports atm, so that part
doesn't change. The scache code is initialized dynamically via the
modules.c logic. That's why the profile code needs an additional
CGEN_ARCH check.
This will allow us to collapse arch configure files more. Merging
the source files will require more future work, but integrating the
cgen & non-cgen worlds itself will take a lot.
This kills off another compile-time option by moving the setting to
the individual arch runtimes. This will allow dynamic selection by
the arch when doing a single build with multiple arches.
The sim_model_init rework is a little funky. In the past it was
disabled entirely if no default model was set. We maintain the
spirit of the logic by gating the fallback logic on whether the
port has defined any models.
We want to do a single build with all arches in one binary which means
we need to namespace sim_machs on a per-arch basis. Move it from a
global variable to the sim description structure so it can be setup at
runtime.
Changing the SIM_MODEL->num from an enum to an int is unfortunate, but
we specifically don't want to maintain a centralized list anymore, and
this was never used directly in common code, just passed to per-arch
callbacks.
Jose E. Marchesi
Andrew Burgess
Mike Frysinger
David Faust
Joel Brobecker