This changes gdbarch to use the "predefault" to initialize its members
inline. This required changing a couple of the Value instantiations
to avoid a use of "gdbarch" during initialization, but on the whole I
think this is better -- it removes a hidden ordering dependency.
Currently, every internal_error call must be passed __FILE__/__LINE__
explicitly, like:
internal_error (__FILE__, __LINE__, "foo %d", var);
The need to pass in explicit __FILE__/__LINE__ is there probably
because the function predates widespread and portable variadic macros
availability. We can use variadic macros nowadays, and in fact, we
already use them in several places, including the related
gdb_assert_not_reached.
So this patch renames the internal_error function to something else,
and then reimplements internal_error as a variadic macro that expands
__FILE__/__LINE__ itself.
The result is that we now should call internal_error like so:
internal_error ("foo %d", var);
Likewise for internal_warning.
The patch adjusts all calls sites. 99% of the adjustments were done
with a perl/sed script.
The non-mechanical changes are in gdbsupport/errors.h,
gdbsupport/gdb_assert.h, and gdb/gdbarch.py.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Change-Id: Ia6f372c11550ca876829e8fd85048f4502bdcf06
This commit adds asserts to gdbarch_register_name that validate the
parameters, and the return value.
The interesting thing here is that gdbarch_register_name is generated
by gdbarch.py, and so, to add these asserts, I need to update the
generation script.
I've added two new arguments for Functions and Methods (as declared in
gdbarch-components.py), these arguments are 'param_checks' and
'result_checks'. Each of these new arguments can be used to list some
expressions that are then used within gdb_assert calls in the
generated code.
The asserts that validate the API as described in the comment I added
to gdbarch_register_name a few commits back; the register number
passed in needs to be a valid cooked register number, and the result
being returned should not be nullptr.
gdbarch implements its own registry-like approach. This patch changes
it to instead use registry.h. It's a rather large patch but largely
uninteresting -- it's mostly a straightforward conversion from the old
approach to the new one.
The main benefit of this change is that it introduces type safety to
the gdbarch registry. It also removes a bunch of code.
One possible drawback is that, previously, the gdbarch registry
differentiated between pre- and post-initialization setup. This
doesn't seem very important to me, though.
After the commit:
commit 08106042d9f5fdff60c129bf33190639f1a98b2a
Date: Thu May 19 13:20:17 2022 +0100
gdb: move the type cast into gdbarch_tdep
GDB would no longer build using g++ 4.8. The issue appears to be some
confusion caused by GDB having 'struct gdbarch_tdep', but also a
templated function called 'gdbarch_tdep'. Prior to the above commit
the gdbarch_tdep function was not templated, and this compiled just
fine. Note that the above commit compiles just fine with later
versions of g++, so this issue was clearly fixed at some point, though
I've not tried to track down exactly when.
In this commit I propose to fix the g++ 4.8 build problem by renaming
'struct gdbarch_tdep' to 'struct gdbarch_tdep_base'. This rename
better represents that the struct is only ever used as a base class,
and removes the overloading of the name, which allows GDB to build
with g++ 4.8.
I've also updated the comment on 'struct gdbarch_tdep_base' to fix a
typo, and the comment on the 'gdbarch_tdep' function, to mention that
in maintainer mode a run-time type check is performed.
Now that filtered and unfiltered output can be treated identically, we
can unify the printf family of functions. This is done under the name
"gdb_printf". Most of this patch was written by script.
After the previous commit, which removes the predicate function
gdbarch_register_type_p, I noticed that the gdbarch->register_type
field was not checked at in the verify_gdbarch function.
More than not being checked, the field wasn't mentioned at all.
I find this strange, I would expect that every field would at least be
mentioned - we already generate comments for some fields saying that
this field is _not_ being checked, so the fact that this field isn't
being checked looks (to me), like this field is somehow slipping
through the cracks.
The comment at the top of gdbarch-components.py tries to explain how
the validation is done. I didn't understand this comment completely,
but, I think this final sentence:
"Otherwise, the check is done against 0 (really NULL for function
pointers, but same idea)."
Means that, if non of the other cases apply, then the field should be
checked against 0, with 0 indicating that the field is invalid (was
not set by the tdep code). However, this is clearly not being done.
Looking in gdbarch.py at the code to generate verify_gdbarch we do
find that there is a case that is not handled, the case where the
'invalid' field is set true True, but non of the other cases apply.
In this commit I propose two changes:
1. Handle the case where the 'invalid' field of a property is set to
True, this should perform a check for the field of gdbarch still
being set to 0, and
2. If the if/else series that generates verify_gdbarch doesn't handle
a property then we should raise an exception. This means that if a
property is added which isn't handled, we should no longer silently
ignore it.
After doing this, I re-generated the gdbarch files and saw that the
following gdbarch fields now had new validation checks:
register_type
believe_pcc_promotion
register_to_value
value_to_register
frame_red_zone_size
displaced_step_restore_all_in_ptid
solib_symbols_extension
Looking at how these are currently set in the various -tdep.c files, I
believe the only one of these that is required to be set for all
architectures is the register_type field.
And so, for all of the other fields, I've changed the property
definition on gdbarch-components.py, setting the 'invalid' field to
False.
Now, after re-generation, the register_type field is checked against
0, thus an architecture that doesn't set_gdbarch_register_type will
now fail during validation. For all the other fields we skip the
validation, in which case, it is find for an architecture to not set
this field.
My expectation is that there should be no user visible changes after
this commit. Certainly for all fields except register_type, all I've
really done is cause some extra comments to be generated, so I think
that's clearly fine.
For the register_type field, my claim is that any architecture that
didn't provide this would fail when creating its register cache, and I
couldn't spot an architecture that doesn't provide this hook. As
such, I think this change should be fine too.
This moves the copyright code from gdbarch.py to a new Python source
file, gdbcopyright.py. The function in this file will find the
copyright dates by scanning the calling script. This will be reused
in a future patch.
This involved minor changes to the output of gdbarch.py. Also, I've
updated copyright.py to remove the reference to gdbarch.sh. We don't
need to mention gdbarch.py there, either.
This changes gdbarch dumping to use filtered output. This seems a bit
better to me, both on the principle that this is an ordinary command,
and because the output can be voluminous, so it may be nice to stop in
the middle.
This commit updates the copyright year in some files where
we have a copyright year outside of the copyright year,
and thus are not included in gdb's copyright.py script.
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 new gdbarch generator is a Python program. It reads the
"components.py" that was created in the previous patch, and generates
gdbarch.c and gdbarch-gen.h.
This is a relatively straightforward translation of the existing .sh
code. It doesn't try very hard to be idiomatic Python or to be
especially smart.
It is, however, incredibly faster:
$ time ./gdbarch.sh
real 0m8.197s
user 0m5.779s
sys 0m3.384s
$ time ./gdbarch.py
real 0m0.065s
user 0m0.053s
sys 0m0.011s
Co-Authored-By: Tom Tromey <tom@tromey.com>
