Given the introduction of the new Armv9.4-a `sysp' insn using the
following syntax:
sysp #<op1>, <Cn>, <Cm>, #<op2>{, <Xt1>, <Xt2>}
and by extension the need to encode 6 assembly operands, extend
Binutils to handle instructions taking 6 operands, up from a previous
maximum of 5.
Indicating the presence of the Armv9.4-a features concerning 128-bit
Page Table Descriptors, 128-bit System Registers and Instructions,
the "+d128" architectural extension flag is added to the list of
possible -march options in Binutils, together with the necessary macro
for encoding d128 instructions.
Add support for compiling build tools with various -Werror settings.
Since the tools don't compile cleanly with the same set of flags as
the rest of the sim code, we need to maintain & test a separate list.
Only bother when not cross-compiling so we don't have to test all the
flags against the build compiler. This should be good enough for our
actual development flows.
Leave the igen code in place as it's meant to be used with newer
(to-be-written) code ported from the ppc version.
The sh code isn't really necessary as the opcodes enums have been
maintained independently from here, and the lists are out-of-sync
already.
Now that the DWARF reader does not use parallel_for_each, we can
remove some of the features that were added just for it: return values
and task sizing.
The thread_pool typed tasks feature could also be removed, but I
haven't done so here. This one seemed less intrusive and perhaps more
likely to be needed at some point.
The previous patches are nearly enough to enable background DWARF
reading. However, this hack in language_defn::get_symbol_name_matcher
causes an early computation of current_language:
/* If currently in Ada mode, and the lookup name is wrapped in
'<...>', hijack all symbol name comparisons using the Ada
matcher, which handles the verbatim matching. */
if (current_language->la_language == language_ada
&& lookup_name.ada ().verbatim_p ())
return current_language->get_symbol_name_matcher_inner (lookup_name);
I considered various options here -- reversing the order of the
checks, or promoting the verbatim mode to not be a purely Ada feature
-- but in the end found that the few calls to this during startup
could be handled more directly.
In the JIT code, and in create_exception_master_breakpoint_hook, gdb
is really looking for a certain kind of symbol (text or data) using a
linkage name. Changing the lookup here is clearer and probably more
efficient as well.
In create_std_terminate_master_breakpoint, the lookup can't really be
done by linkage name (it would require relying on a certain mangling
scheme, and also may trip over versioned symbols) -- but we know that
this spot is C++-specific, and so the language ought to be temporarily
set to C++ here.
After this patch, the "file" case is much faster:
(gdb) file /tmp/gdb
2023-10-23 13:16:54.456 - command started
Reading symbols from /tmp/gdb...
2023-10-23 13:16:54.520 - command finished
Command execution time: 0.225906 (cpu), 0.064313 (wall)
lookup_minimal_symbol_text always loops over all objfiles, even when
an objfile is passed in as an argument. This patch changes the
function to loop over the minimal number of objfiles in the latter
situation.
When gdb starts up with a symbol file, it uses the program's "main" to
decide the "static context" and the initial language. With background
DWARF reading, this means that gdb has to wait for a significant
amount of DWARF to be read synchronously.
This patch introduces lazy language setting. The idea here is that in
many cases, the prompt can show up early, making gdb feel more
responsive.
This changes the 'current_language' global to be a macro that wraps a
function call. This change will let a subsequent patch introduce lazy
language setting.
quick_symbol_functions::read_partial_symbols is no longer implemented,
so both it and quick_symbol_functions::can_lazily_read_symbols can be
removed. This allows for other functions to be removed as well.
Note that SYMFILE_NO_READ is now pretty much dead. I haven't removed
it here -- but could if that's desirable. I tend to think that this
functionality would be better implemented in the core; but whenever I
dive into the non-DWARF readers it is pretty depressing.
dwarf2_has_info and dwarf2_initialize_objfile are only separate
because the DWARF reader implemented lazy psymtab reading. However,
now that this is gone, we can simplify the public DWARF API again.
This patch rearranges the DWARF reader so that more work is done in
the background. This is PR symtab/29942.
The idea here is that there is only a small amount of work that must
be done on the main thread when scanning DWARF -- before the main
scan, the only part is mapping the section data.
Currently, the DWARF reader uses the quick_symbol_functions "lazy"
functionality to defer even starting to read. This patch instead
changes the reader to start reading immediately, but doing more in
worker tasks.
Before this patch, "file" on my machine:
(gdb) file /tmp/gdb
2023-10-23 12:29:56.885 - command started
Reading symbols from /tmp/gdb...
2023-10-23 12:29:58.047 - command finished
Command execution time: 5.867228 (cpu), 1.162444 (wall)
After the patch, more work is done in the background and so this takes
a bit less time:
(gdb) file /tmp/gdb
2023-10-23 13:25:51.391 - command started
Reading symbols from /tmp/gdb...
2023-10-23 13:25:51.712 - command finished
Command execution time: 1.894500 (cpu), 0.320306 (wall)
I think this could be further sped up by using the shared library load
map to avoid objfile loops like the one in expand_symtab_containing_pc
-- it seems like the correct objfile could be chosen more directly.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29942
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30174
This changes the cooked index code to wait for threads in its
public-facing API. That is, the waits are done in cooked_index now,
and never in the cooked_index_shard. Centralizing this decision makes
it easier to wait for other events here as well.
For testing, it's sometimes convenient to be able to request that
DWARF reading be done synchronously. This patch adds a new "maint"
setting for this purpose.
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
This adds a new compute_main_name method to quick_symbol_functions.
Currently there are no implementations of this, but a subsequent patch
will add one.
When DWARF reading is done in the background,
read_addrmap_from_aranges will be called from a worker thread.
Because warnings can't be emitted from these threads, this patch adds
a new deferred_warnings parameter to the function, letting the caller
control exactly how the warnings are emitted.
This patch changes the way complaint works in a background thread.
The new approach requires installing a complaint interceptor in each
worker, and then the resulting complaints are treated as one of the
results of the computation. This change is needed for a subsequent
patch, where installing a complaint interceptor around a parallel-for
is no longer a viable approach.
This changes gdb to ensure that gdb's BFD cache is guarded by a lock.
This avoids any races when multiple threads might open a BFD (and thus
use the BFD cache) at the same time.
Currently, this change is not needed because the the main thread waits
for some DWARF scanning to be completed before returning. The only
locking that's required is when opening DWO files, and there's a local
lock to this end in dwarf2/read.c.
However, in the coming patches, the DWARF reader will begin its work
earlier, in the background. This means there is the potential for the
DWARF reader and other code on the main thread to both attempt to open
BFDs at the same time.
This adds a couple of calls to bfd_cache_close at points where a BFD
isn't actively needed by gdb. Normally at these points, all the
needed section data is already mapped, so we can simply close the file
descriptor. This is harmless at worst, because if this is needed
after all, the BFD file descriptor cache will reopen it.
This changes the DWZ code to pre-read the section data and somewhat
simplify the DWZ API. This makes it easier to add the bfd_cache_close
call to the new dwarf2_read_dwz_file function -- after this is done,
there shouldn't be a reason to keep the BFD's file descriptor open.
The DWO code in the DWARF reader currently uses objfile::intern. This
accesses a shared data structure and so would be racy when used from
multiple threads. I don't believe this can happen right now, but
background reading could provoke this, and in any case it's better to
avoid this, just to be sure.
This patch changes this code to just use a std::string. A new type is
introduced to do hash table lookups, to avoid unnecessary copies.
This logic dates back to the original import, and seems to be for
handling systems where `rm -f` (i.e. no files) would error out.
None of that is relevant for us with current automake, so drop it.
Some compilers don't understand the semctl API and think it's an input
argument even when it's used as an output, and then complains that it
is being used uninitialized. Zero it out explicitly to workaround it.
This adds some runtime overhead, but should be fairly minor as it's a
small stack buffer, and shouldn't be that relevant relative to all the
other logic in these functions.
The cgen code uses DI as int64_t and UDI as uint64_t. The DI macros
are used to construct 64-bit values from 32-bit values (for the low
and high parts). The MAKEDI macro casts the high 32-bit value to a
signed 32-bit value before shifting. If this created a negative
value, this would be undefined behavior according to the C standard.
All we care about is shifting the 32-bits as they are to the high
32-bits, not caring about sign extension (since there's nothing left
to shift into), and the low 32-bits being empty. This is what we
get from shifting an unsigned value, so cast it to unsigned 32-bit
to avoid undefined behavior.
While we're here, change the SETLODI macro to truncate the lower
value to 32-bits before we set it. If it was passing in a 64-bit
value, those high bits would get included too, and that's not what
we want.
Similarly, tweak the SETHIDI macro to cast the value to an unsigned
64-bit instead of a signed 64-bit. If the value was only 32-bits,
the behavior would be the same. If it happened to be signed 64-bit,
it would trigger the undefined behavior too.
This patch adds linker support to patch R_BPF_64_NODYLD32 relocations.
The implementation was based on comments and code in LLVM, as the GNU
toolchain does not uses this relocation type.
Currently, only mipsisa32-linux and mipsisa32el-linux is marked
as addr32, which make mipsisa32rN(el) not marked.
This change can fix 2 test failures on mipsisa32rN(el)-linux:
FAIL: MIPS MIPS64 MIPS-3D ASE instructions (-mips3d flag)
FAIL: MIPS MIPS64 MDMX ASE instructions (-mdmx flag)
These failures don't happen for mipsisa32rN-mti-elf etc,
due to that, the output is set as NO_ABI instead of O32, then
gas won't warn:
`fp=64' used with a 32-bit ABI
Maybe, we should change this behaivour in future.
This patch adds AArch32 support for -march=armv8.9-a and
-march=armv9.4-a. The behaviour of the new options can be
expressed using a combination of existing feature flags
and tables.
The cpu_arch_ver entries for ARM_ARCH_V9_4A and ARM_ARCH_V8_9A
are technically redundant but it including them for macro code
consistency across architectures.
When running test-case gdb.base/vfork-follow-parent.exp it passes fine, but
when running it with "taskset -c 0" I run into:
...
(gdb) inferior 1^M
[Switching to inferior 1 [process 26606] (vfork-follow-parent-exit)]^M
[Switching to thread 1.1 (process 26606)]^M
(gdb) Reading symbols from vfork-follow-parent-exit...^M
FAIL: $exp: exec_file=vfork-follow-parent-exit: target-non-stop=on: \
non-stop=off: resolution_method=schedule-multiple: inferior 1 (timeout)
...
Fix this by using -no-prompt-anchor.
Tested on x86_64-linux.
PR testsuite/31166
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31166
Also recognized are aarch64-*-gnu tagrets, e.g. aarch64-pc-gnu or
aarch64-unknown-gnu.
The ld/emulparams/aarch64gnu.sh file is (for now) identical to aarch64fbsd.sh,
or to aarch64linux.sh with Linux-specific logic removed; and mainly different
from the generic aarch64elf.sh in that it does not set EMBEDDED=yes.
Coupled with a corresponding GCC patch, this produces a toolchain that can
sucessfully build working binaries targeting aarch64-gnu.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
On aarch64-linux, with gcc 13.2.1, I run into:
...
(gdb) backtrace^M
#0 break_here () at solib-search.c:30^M
#1 0x0000fffff7f20194 in lib2_func4 () at solib-search-lib2.c:50^M
#2 0x0000fffff7f70194 in lib1_func3 () at solib-search-lib1.c:50^M
#3 0x0000fffff7f20174 in lib2_func2 () at solib-search-lib2.c:30^M
#4 0x0000fffff7f70174 in lib1_func1 () at solib-search-lib1.c:30^M
#5 0x00000000004101b4 in main () at solib-search.c:23^M
(gdb) PASS: gdb.base/solib-search.exp: \
backtrace (with wrong libs) (data collection)
FAIL: gdb.base/solib-search.exp: backtrace (with wrong libs)
...
The FAIL is generated by this code in the test-case:
...
if { $expect_fail } {
# If the backtrace output is correct the test isn't sufficiently
# testing what it should.
if { $count == $total_expected } {
set fail 1
}
...
The test-case:
- builds two versions of two shared libs, a "right" and "wrong" version, the
difference being an additional dummy function (called spacer function),
- uses the "right" version to generate a core file,
- uses the "wrong" version to interpret the core file, and
- generates a backtrace.
The intent is that the backtrace is incorrect due to using the "wrong"
version, but actually it's correct. This is because the spacer functions
aren't large enough.
Fix this by increasing the size of the spacer functions by adding a dummy
loop, after which we have, as expected, an incorrect backtrace:
...
(gdb) backtrace^M
#0 break_here () at solib-search.c:30^M
#1 0x0000fffff7f201c0 in ?? ()^M
#2 0x0000fffff7f20174 in lib2_func2 () at solib-search-lib2.c:30^M
#3 0x0000fffff7f20174 in lib2_func2 () at solib-search-lib2.c:30^M
#4 0x0000fffff7f70174 in lib1_func1 () at solib-search-lib1.c:30^M
#5 0x00000000004101b4 in main () at solib-search.c:23^M
(gdb) PASS: gdb.base/solib-search.exp: \
backtrace (with wrong libs) (data collection)
PASS: gdb.base/solib-search.exp: backtrace (with wrong libs)
...
Tested on aarch64-linux.
Since 0x66 is the opcode prefix for adcx, it is wrong to use the 'S'
prefix:
'S' => print 'w', 'l' or 'q' if suffix_always is true
on adcx. Add
'L' => print 'l' or 'q' if suffix_always is true
replace S with L on adcx and adox.
gas/
PR binutils/31219
* testsuite/gas/i386/suffix.d: Updated.
* testsuite/gas/i386/x86-64-suffix.d: Likewise.
* testsuite/gas/i386/suffix.s: Add tests for adcx and adox.
* testsuite/gas/i386/x86-64-suffix.s: Likewise.
opcodes/
PR binutils/31219
* i386-dis.c: Add the 'L' suffix.
(prefix_table): Replace S with L on adcx and adox.
(putop): Handle the 'L' suffix.
Rename the temp var to avoid shadowing another one:
.../sim/cris/semcrisv10f-switch.c:11032:22: error: declaration of ‘tmp_tmpb’ shadows a previous local [-Werror=shadow=compatible-local]
11032 | tmp_tmpb = ({ SI tmp_tmpb;
| ^~~~~~~~
.../sim/cris/semcrisv10f-switch.c:11031:24: note: shadowed declaration is here
11031 | tmp_tmpres = ({ SI tmp_tmpb;
| ^~~~~~~~
The condition & swap code decoder only checks known bits and sets
based on that. If the variable is out of range, it ends up returning
uninitialized data. Turn that case into a hard error.
This fixes build warnings like:
sim/cris/semcrisv10f-switch.c:13115:11: error:
variable 'tmp_condres' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
