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.
Move these options up to the common dir so we only test & export
them once across all ports. It makes it available to targets that
aren't cgen-based, but those will just ignore the settings, so it
shouldn't be an issue.
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 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.
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.
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.
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.
This patch fixes the following problems:
- Missing includes in several files leading to implicit function
declarations.
- Missing prototype for bpf_trace_printk in bpf-helpers.h
- The simulator bitsize was set to 32 bits, causing truncation of
the program counter.
Tested in bpf-unknown-none.
sim/ChangeLog:
2020-09-03 Jose E. Marchesi <jose.marchesi@oracle.com>
* bpf/bpf.c: Include bpf-helpers.h.
* bpf/bpf-helpers.h: Provide a prototype for bpf_trace_printk.
* bpf/configure.ac: Set simulator bitsize to 64.
* bpf/configure (includedir): Regenerate.
* bpf/sim-if.c: Include stdlib.h.
* bpf/traps.c: Likewise.
