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.
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.
Start with splitting out sim/callback.h.
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.
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.
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.
A random grab bag of minor fixes to enable -Werror for this port.
Disable h8_set_macS for now as it's unused.
Initialize trace & intMask before using them.
Mark local set_h8300h function static.
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:
3e019bdc20eb81b91ab5bc774386201b874c0bac
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.
GCC gives a -Wsequence-point warning for this code in the h8300 sim.
The bug is that memory_size is both assigned and used in the same
expression. The fix is to assign after the print.
sim/h8300/ChangeLog
2021-04-08 Tom Tromey <tom@tromey.com>
* compile.c (init_pointers): Fix sequence point warning.
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.
All the scripts were using this implicitly already, so there's no real
change for them, but we want to call it explicitly as the CPP tool is
used to generate nltvals.def.
This file is quite large and is getting unmanageable. Split it apart
to follow aclocal best practices by putting one-macro-per-file. There
shouldn't be any real functional changes here as can be seen in the
configure script regens.
Rather than hand maintain m4 includes in various autotool files,
use AC_CONFIG_MACRO_DIRS to declare the relevant search paths.
This simplifies the code, makes it more robust, and cleans out
unused logic from configure.
The AC_CONFIG_HEADER macro is long deprecated, so switch to the
newer form. This also gets rid of the position limitation, and
drops support for an argument to SIM_AC_COMMON which we haven't
used anywhere.
These settings might have made sense in darker compiler times, but I
think they're largely obsolete now. Looking through the values that
get used in HDEFINES, it's quite limited, and configure itself should
handle them. If we still need something, we can leverage standard
autoconf macros instead, after we get a clear user report.
TDEFINES was never set anywhere and was always empty, so prune that.
The h8300 sim has its own implementation for memory handling that I'd
like to replace with the common sim memory code. However, it's got a
weird bit of code it calls "eightbit mem" that makes this not as easy
as it would otherwise be. The code has this comment:
/* These define the size of main memory for the simulator.
Note the size of main memory for the H8/300H is only 256k. Keeping it
small makes the simulator run much faster and consume less memory.
The linker knows about the limited size of the simulator's main memory
on the H8/300H (via the h8300h.sc linker script). So if you change
H8300H_MSIZE, be sure to fix the linker script too.
Also note that there's a separate "eightbit" area aside from main
memory. For simplicity, the simulator assumes any data memory reference
outside of main memory refers to the eightbit area (in theory, this
can only happen when simulating H8/300H programs). We make no attempt
to catch overlapping addresses, wrapped addresses, etc etc. */
I've read the H8/300 Programming Manual and the H8/300H Software Manual
and can't find documentation on it. The closest I can find is the bits
about the exception vectors, but that sounds like a convention where the
first 256 bytes of memory are used for a special purpose. The sim will
actually allocate a sep memory buffer of 256 bytes and you address it by
accessing anywhere outside of main memory. e.g. I would expect code to
access it like:
uint32_t *data = (void *)0;
data[0] = reset_exception_vector;
not like the sim expects like:
uint8_t *data = (void *)0x1000000;
data[0] = ...;
The gcc manual has an "eightbit_data" attribute:
Use this attribute on the H8/300, H8/300H, and H8S to indicate that
the specified variable should be placed into the eight-bit data
section. The compiler generates more efficient code for certain
operations on data in the eight-bit data area. Note the eight-bit
data area is limited to 256 bytes of data.
And the gcc code implies that it's accessed via special addressing:
eightbit_data: This variable lives in the 8-bit data area and can
be referenced with 8-bit absolute memory addresses.
I'm fairly certain these are referring to the 8-bit addressing modes
that allow access to 0xff00 - 0xffff with only an 8-bit immediate.
They aren't completely separate address spaces which this eightbit
memory buffer occupies.
But the sim doesn't access its eightbit memory based on specific insns,
it does it purely on the addresses requested.
Unfortunately, much of this code was authored by Michael Snyder, so I
can't ask him :(. I asked Renesas support and they didn't know:
https://renesasrulz.com/the_vault/f/archive-forum/6952/question-about-eightbit-memory
So I've come to the conclusion that this was a little sim-specific hack
done for <some convenience> and has no relation to real hardware. And
as such, let's drop it until someone notices and can provide a reason
for why we need to support it.
We want all ports to opt into extra warnings as the default compiler
settings lets a lot slide. Opt all the ports that haven't already in
to the warning system. None of them build with -Werror, so disable
that by default. Hopefully someone finds these important enough to
start fixing at some point.
Since we require C11 now, we can assume many headers exist, and
clean up all of the conditional includes. It's not like any of
this code actually accounted for the headers not existing, just
whether we could include them.
The strings.h cleanup is a little nuanced: it isn't in C11, but
every use of it in the codebase will include strings.h only if
string.h doesn't exist. Since we now assume the C11 string.h
exists, we'll never include strings.h, so we can delete it.
With GDB requiring a C++11 compiler now, this hopefully shouldn't
be a big deal. It's been 10 years since C11 came out, so should
be plenty of time to upgrade.
This will allow us to start cleaning up random header logic and
many of our non-standard custom types.
This is in preparation for converting h8300 over to the common memory
framework. It's not clear how much of a speed gain this was providing
in the first place -- a naive test of ~400k insns (using shlr.s) shows
that this code actually slowed things down a bit.
If anyone really cares about h8300 anymore, they can migrate to the
common insn caching logic.
