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.
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.
These ports only use the pieces that have been unified, so we can
merge them into the common configure script and get rid of their
unique one entirely.
We still compile & link separate run programs, and have dedicated
subdir Makefiles, but the configure script portion is merged.
The sim-hardware configure option allows builders to select a set of
device models to enable. But this seems like unnecessary overkill:
the existence of individual device models doesn't affect performance
at all as they are only enabled at runtime if the config uses them,
and individually these are all <5KB a piece. Stripping off a total
of ~50KB from a ~1MB binary doesn't seem useful, and it's extremely
unlikely anyone will ever bother.
So let's simplify the configure/make logic by turning sim-hardware
into a boolean option like many of the other sim options. Any ports
that have unique device models will declare them in their Makefile
instead of at configure time. This will allow us to (eventually)
unify the setting into the common dir.
Move these options up to the common dir so we only test & export
them once across all ports. This takes a page from the cgen maint
logic to make $(MAINT) work for non-automake Makefiles which will
allow us to merge it together.
Move these options up to the common dir so we only test & export
them once across all ports. It also enables -Werror usage on the
common files we've been pulling out of arch subdirs.
For the ports that still don't build with -Werror, rather than disable
the flag at configure time, do it at make time. This will allow us to
unify these tests in the common sim configure script.
The sim-basics.h is too big and includes too many things. This leads
to some arch's sim-main.h having circular loop issues with defs, and
makes it hard to separate out common objects from arch-specific defs.
By splitting up sim-basics.h and killing off sim-main.h, it'll make
it easier to separate out the two.
The m4 macro has 2 args: the "wire" settings (which represents the
hardwired port behavior), and the default settings (which are used
if nothing else is specified). If none are specified, the arch is
expected to support both, and the value will be probed based on the
user runtime options or the input program.
Only two arches today set the default value (bpf & mips). We can
probably let this go as it only shows up in one scenario: the sim
is invoked, but with no inputs, and no user endian selection. This
means bpf will not behave like the other arches: an error is shown
and forces the user to make a choice. If an input program is used
though, we'll still switch the default to that. This allows us to
remove the WITH_DEFAULT_TARGET_BYTE_ORDER setting.
For the ports that set a "wire" endian, move it to the runtime init
of the respective sim_open calls. This allows us to change the
WITH_TARGET_BYTE_ORDER to purely a user-selected configure setting
if they want to force a specific endianness.
With all the endian logic moved to runtime selection, we can move
the configure call up to the common dir so we only process it once
across all ports.
The ppc arch was picking the wire endian based on the target used,
but since we weren't doing that for other biendian arches, we can
let this go too. We'll rely on the input selecting the endian, or
make the user decide.
All of the settings in here are handled by the common top-level
config.h, so drop the individual arch-config.h files entirely.
This will also help guarantee that we don't add any new arch
specific defines that would affect common code which will help
with the effort of unifying them.
The common code already calls this, so no need to do so in arch dirs.
We leave the calls that disable -Werror. This will help unify the
configure scripts.
Currently, the sim-config module will abort if alignment settings
haven't been specified by the port's configure.ac. This is a bit
weird when we've allowed SIM_AC_OPTION_ALIGNMENT to seem like it's
optional to use. Thus everyone invokes it.
There are 4 alignment settings, but really only 2 matters: strict
and nonstrict. The "mixed" setting is just the default ("unset"),
and "forced" isn't used directly by anyone (it's available as a
runtime option for some ports).
The m4 macro has 2 args: the "wire" settings (which represents the
hardwired port behavior), and the default settings (which are used
if nothing else is specified). If none are specified, then the
build won't work (see above as if SIM_AC_OPTION_ALIGNMENT wasn't
called). If default settings are provided, then that is used, but
we allow the user to override at runtime. Otherwise, the "wire"
settings are used and user runtime options to change are ignored.
Most ports specify a default, or set the "wire" to nonstrict. A
few set "wire" to strict, but it's not clear that's necessary as
it doesn't make the code behavior, by default, any different. It
might make things a little faster, but we should provide the user
the choice of the compromises to make: force a specific mode at
compile time for faster runtime, or allow the choice at runtime.
More likely it seems like an oversight when these ports were
initially created, and/or copied & pasted from existing ports.
With all that backstory, let's get to what this commit does.
First kill off the idea of a compile-time default alignment and
set it to nonstrict in the common code. For any ports that want
strict alignment by default, that code is moved to sim_open while
initializing the sim. That means WITH_DEFAULT_ALIGNMENT can be
completely removed.
Moving the default alignment to the runtime also allows removal
of setting the "wire" settings at configure time. Which allows
removing of all arguments to SIM_AC_OPTION_ALIGNMENT and moving
that call to common code.
The macro logic can be reworked to not pass WITH_ALIGNMENT as -D
CPPFLAG and instead move it to config.h.
All of these taken together mean we can hoist the macro up to the
top level and share it among all sims so behavior is consistent
among all the ports.
Move these options up to the common dir so we only test & export
them once across all ports. The AC_INIT macro does a lot of the
heavy lifting already which allows further simplification.
Move these options up to the common dir so we only test & export
them once across all ports.
The ppc code needs a little extra care with its trace settings as
it's not exactly the same API as the common code. The other knobs
are the same though.
Move the various platform tests up a level to avoid duplication
across the ports. When building multiple versions, this speeds
things up a bit.
For now we move the obvious stuff up a level, but we don't turn
own the config.h entirely just yet -- we still have some tests
related to libraries that need consideration.
Currently all ports have to declare sim_state themselves in their
sim-main.h and then embed the common sim_state_base & sim_cpu in it.
This dynamic makes it impossible to share common object code among
multiple ports because the core data structure is always different.
Let's invert this relationship: common code declares sim_state, and
if the port actually needs state on a per-instance basis, it can use
the new arch_data field for it. Most ports don't actually use it,
so they don't need to declare anything at all.
This is the first in a series of changes: it adds a define to select
between the old & new layouts, then converts all the ports that don't
need custom state over to the new layout.
The defs.h header will take care of including the various config.h
headers. For now, it's just config.h, but we'll add more when we
integrate gnulib in.
This header should be used instead of config.h, and should be the
first include in every .c file. We won't rely on the old behavior
where we expected files to include the port's sim-main.h which then
includes the common sim-basics.h which then includes config.h. We
have a ton of code that includes things before sim-main.h, and it
sometimes needs to be that way. Creating a dedicated header avoids
the ordering mess and implicit inclusion that shows up otherwise.
The gdb/callback.h & gdb/remote-sim.h headers have nothing to do with
gdb and are really definitions for the libsim API under the sim/ tree.
While gdb uses those headers as a client, it's not specific to it. So
create a new sim/ namespace and move the headers there.
This is needed when building for a target whose ar & ranlib are
incompatible with the current build system. For example, building
for Windows on a Linux system.
Then manually import the automake rule for libigen.a, but tweak the
tool variables to use the FOR_BUILD variants.
While libiberty provides a definition for this for systems that lack
the function (e.g. Windows), it doesn't provide a prototype. So add
our own local copy in the one file that uses the func.
Force this on for all ports. We have a few common models that can
be used, so make them generally available. If the port doesn't use
any hardware (the default), then behavior is unchanged.
When building with clang, we get:
error: unknown warning option '-Wmissing-parameter-type' [-Werror,-Wunknown-warning-option]
This is because clang only warns by default when encountering an unknown
warning option, and the probe for supported warning flags is done
without -Werror. All flags are therefore accepted by configure, but
then it breaks when actually compiling a source file with -Werror.
This is equivalent to this commit in gdb:
3e019bdc20
gdb: Use -Werror when checking for (un)supported warning flags
We then see some other compilation errors when building with clang and
-Werror, they can be dealt with later.
This avoids duplicate tests for functions between common m4, arches,
and any other sources that would trigger func tests.
Also manually delete known duplicate function tests between the m4,
bfin, and v850 ports.
This fixes a problem that occurs when compiled by gcc-10, as the code
is relying on undefined overflow behavior. This is fixed by replacing
compares between 32-bit and 64-bit results with compares that just use
the 64-bit results with a cast.
PR sim/27483
* simulator.c (set_flags_for_add32): Compare uresult against
itself. Compare sresult against itself.
Rather than require $AR be set and then default to `ar`, use the
standard AC_CHECK_TOOL helper to find a good prefixed tool. In
practice this shouldn't change much as we seem to have macros in
the tree that were already setting it up, but we shouldn't rely
on that implicitly.
