This commit builds on the previous series of commits to share the
target description caching code between GDB and gdbserver for
x86/Linux targets.
The objective of this commit is to move the four functions (2 each of)
i386_linux_read_description and amd64_linux_read_description into the
gdb/arch/ directory and combine them so we have just a single copy of
each. Then GDB, gdbserver, and the in-process-agent (IPA) will link
against these shared functions.
One curiosity with this patch is the function
x86_linux_post_init_tdesc. On the gdbserver side the two functions
amd64_linux_read_description and i386_linux_read_description have some
functionality that is not present on the GDB side, there is some
additional configuration that is performed as each target description
is created, to setup the expedited registers.
To support this I've added the function x86_linux_post_init_tdesc.
This function is called from the two *_linux_read_description
functions, but is implemented separately for GDB and gdbserver.
An alternative approach that avoids adding x86_linux_post_init_tdesc
would be to have x86_linux_tdesc_for_tid return a non-const target
description, then in x86_target::low_arch_setup we could inspect the
target description to figure out if it is 64-bit or not, and modify
the target description as needed. In the end I think that adding the
x86_linux_post_init_tdesc function is the simpler solution.
The contents of gdbserver/linux-x86-low.cc have moved to
gdb/arch/x86-linux-tdesc-features.c, and gdbserver/linux-x86-tdesc.h
has moved to gdb/arch/x86-linux-tdesc-features.h, this change leads to
some updates in the #includes in the gdbserver/ directory.
This commit also changes how target descriptions are cached.
Previously both GDB and gdbserver used static C-style arrays to act as
the tdesc cache. This was fine, except for two problems. Either the
C-style arrays would need to be placed in x86-linux-tdesc-features.c,
which would allow us to use the x86_linux_*_tdesc_count_1() functions
to size the arrays for us, or we'd need to hard code the array sizes
using separate #defines, which we'd then have to keep in sync with the
rest of the code in x86-linux-tdesc-features.c.
Given both of these problems I decided a better solution would be to
just switch to using a std::unordered_map to act as the cache. This
will resize automatically, and we can use the xcr0 value as the key.
At first inspection, using xcr0 might seem to be a problem; after all
the {i386,amd64}_create_target_description functions take more than
just the xcr0 value. However, this patch is only for x86/Linux
targets, and for x86/Linux all of the other flags passed to the tdesc
creation functions have constant values and so are irrelevant when we
consider tdesc caching.
For testing I've done the following:
- Built on x86-64 GNU/Linux for all targets, and just for the native
target,
- Build on i386 GNU/Linux for all targets, and just for the native
target,
- Build on a 64-bit, non-x86 GNU/Linux for all targets, just for the
native target, and for targets x86_64-*-linux and i386-*-linux.
Approved-By: Felix Willgerodt <felix.willgerodt@intel.com>
This commit is part of a series to share more of the x86 target
description creation code between GDB and gdbserver.
Unlike previous commits which were mostly refactoring, this commit is
the first that makes a real change, though that change should mostly
be for gdbserver; I've largely adopted the "GDB" way of doing things
for gdbserver, and this fixes a real gdbserver bug.
On a x86-64 Linux target, running the test:
gdb.server/connect-with-no-symbol-file.exp
results in two core files being created. Both of these core files are
from the inferior process, created after gdbserver has detached.
In this test a gdbserver process is started and then, after gdbserver
has started, but before GDB attaches, we either delete the inferior
executable, or change its permissions so it can't be read. Only after
doing this do we attempt to connect with GDB.
As GDB connects to gdbserver, gdbserver attempts to figure out the
target description so that it can send the description to GDB, this
involves a call to x86_linux_read_description.
In x86_linux_read_description one of the first things we do is try to
figure out if the process is 32-bit or 64-bit. To do this we look up
the executable via the thread-id, and then attempt to read the
architecture size from the executable. This isn't going to work if
the executable has been deleted, or is no longer readable.
And so, as we can't read the executable, we default to an i386 target
and use an i386 target description.
A consequence of using an i386 target description is that addresses
are assumed to be 32-bits. Here's an example session that shows the
problems this causes. This is run on an x86-64 machine, and the test
binary (xx.x) is a standard 64-bit x86-64 binary:
shell_1$ gdbserver --once localhost :54321 /tmp/xx.x
shell_2$ gdb -q
(gdb) set sysroot
(gdb) shell chmod 000 /tmp/xx.x
(gdb) target remote :54321
Remote debugging using :54321
warning: /tmp/xx.x: Permission denied.
0xf7fd3110 in ?? ()
(gdb) show architecture
The target architecture is set to "auto" (currently "i386").
(gdb) p/x $pc
$1 = 0xf7fd3110
(gdb) info proc mappings
process 2412639
Mapped address spaces:
Start Addr End Addr Size Offset Perms objfile
0x400000 0x401000 0x1000 0x0 r--p /tmp/xx.x
0x401000 0x402000 0x1000 0x1000 r-xp /tmp/xx.x
0x402000 0x403000 0x1000 0x2000 r--p /tmp/xx.x
0x403000 0x405000 0x2000 0x2000 rw-p /tmp/xx.x
0xf7fcb000 0xf7fcf000 0x4000 0x0 r--p [vvar]
0xf7fcf000 0xf7fd1000 0x2000 0x0 r-xp [vdso]
0xf7fd1000 0xf7fd3000 0x2000 0x0 r--p /usr/lib64/ld-2.30.so
0xf7fd3000 0xf7ff3000 0x20000 0x2000 r-xp /usr/lib64/ld-2.30.so
0xf7ff3000 0xf7ffb000 0x8000 0x22000 r--p /usr/lib64/ld-2.30.so
0xf7ffc000 0xf7ffe000 0x2000 0x2a000 rw-p /usr/lib64/ld-2.30.so
0xf7ffe000 0xf7fff000 0x1000 0x0 rw-p
0xfffda000 0xfffff000 0x25000 0x0 rw-p [stack]
0xff600000 0xff601000 0x1000 0x0 r-xp [vsyscall]
(gdb) info inferiors
Num Description Connection Executable
* 1 process 2412639 1 (remote :54321)
(gdb) shell cat /proc/2412639/maps
00400000-00401000 r--p 00000000 fd:03 45907133 /tmp/xx.x
00401000-00402000 r-xp 00001000 fd:03 45907133 /tmp/xx.x
00402000-00403000 r--p 00002000 fd:03 45907133 /tmp/xx.x
00403000-00405000 rw-p 00002000 fd:03 45907133 /tmp/xx.x
7ffff7fcb000-7ffff7fcf000 r--p 00000000 00:00 0 [vvar]
7ffff7fcf000-7ffff7fd1000 r-xp 00000000 00:00 0 [vdso]
7ffff7fd1000-7ffff7fd3000 r--p 00000000 fd:00 143904 /usr/lib64/ld-2.30.so
7ffff7fd3000-7ffff7ff3000 r-xp 00002000 fd:00 143904 /usr/lib64/ld-2.30.so
7ffff7ff3000-7ffff7ffb000 r--p 00022000 fd:00 143904 /usr/lib64/ld-2.30.so
7ffff7ffc000-7ffff7ffe000 rw-p 0002a000 fd:00 143904 /usr/lib64/ld-2.30.so
7ffff7ffe000-7ffff7fff000 rw-p 00000000 00:00 0
7ffffffda000-7ffffffff000 rw-p 00000000 00:00 0 [stack]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
(gdb)
Notice the difference between the mappings reported via GDB and those
reported directly from the kernel via /proc/PID/maps, the addresses of
every mapping is clamped to 32-bits for GDB, while the kernel reports
real 64-bit addresses.
Notice also that the $pc value is a 32-bit value. It appears to be
within one of the mappings reported by GDB, but is outside any of the
mappings reported from the kernel.
And this is where the problem arises. When gdbserver detaches from
the inferior we pass the inferior the address from which it should
resume. Due to the 32/64 bit confusion we tell the inferior to resume
from the 32-bit $pc value, which is not within any valid mapping, and
so, as soon as the inferior resumes, it segfaults.
If we look at how GDB (not gdbserver) figures out its target
description then we see an interesting difference. GDB doesn't try to
read the executable. Instead GDB uses ptrace to query the thread's
state, and uses this to figure out the if the thread is 32 or 64 bit.
If we update gdbserver to do it the "GDB" way then the above problem
is resolved, gdbserver now sees the process as 64-bit, and when we
detach from the inferior we give it the correct 64-bit address, and
the inferior no longer segfaults.
Now, I could just update the gdbserver code, but better, I think, to
share one copy of the code between GDB and gdbserver in gdb/nat/.
That is what this commit does.
The cores of x86_linux_read_description from gdbserver and
x86_linux_nat_target::read_description from GDB are moved into a new
file gdb/nat/x86-linux-tdesc.c and combined into a single function
x86_linux_tdesc_for_tid which is called from each location.
This new function does things mostly the GDB way, some changes are
needed to allow for the sharing; we now take some pointers for where
the shared code can cache the xcr0 and xsave layout values.
Another thing to note about this commit is how the functions
i386_linux_read_description and amd64_linux_read_description are
handled. For now I've left these function as implemented separately
in GDB and gdbserver. I've moved the declarations of these functions
into gdb/arch/{i386,amd64}-linux-tdesc.h, but the implementations are
left where they are.
A later commit in this series will make these functions shared too,
but doing this is not trivial, so I've left that for a separate
commit. Merging the declarations as I've done here ensures that
everyone implements the function to the same API, and once these
functions are shared (in a later commit) we'll want a shared
declaration anyway.
Reviewed-By: Felix Willgerodt <felix.willgerodt@intel.com>
Acked-By: John Baldwin <jhb@FreeBSD.org>
Move the declarations out of defs.h, and the implementations out of
findvar.c.
I opted for a new file, because this functionality of converting
integers to bytes and vice-versa seems a bit to generic to live in
findvar.c.
Change-Id: I524858fca33901ee2150c582bac16042148d2251
Approved-By: John Baldwin <jhb@FreeBSD.org>
Now that defs.h, server.h and common-defs.h are included via the
`-include` option, it is no longer necessary for source files to include
them. Remove all the inclusions of these files I could find. Update
the generation scripts where relevant.
Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837
Approved-By: Pedro Alves <pedro@palves.net>
This commit builds on the previous series of commits to share the
target description caching code between GDB and gdbserver for
x86/Linux targets.
The objective of this commit is to move the four functions (2 each of)
i386_linux_read_description and amd64_linux_read_description into
gdb/nat/x86-linux-tdesc.c and combine them so we have just a single
copy of each. Then both GDB and gdbserver will link against these
shared functions.
It is worth reading the description of the previous commit to see why
this merging is not as simple as it seems: on the gdbserver side we
actually have two users of these functions, gdbserver itself, and the
in process agent (IPA).
However, the previous commit streamlined the gdbserver code, and so
now it is simple to move the two functions along with all their
support functions from the gdbserver directory into the gdb/nat/
directory, and then GDB is fine to call these functions.
One small curiosity with this patch is the function
x86_linux_post_init_tdesc. On the gdbserver side the two functions
amd64_linux_read_description and i386_linux_read_description have some
functionality that is not present on the GDB side, that is some
additional configuration that is performed as each target description
is created to setup the expedited registers.
To support this I've added the function x86_linux_post_init_tdesc.
This function is called from the two *_linux_read_description
functions, but is implemented separately for GDB and gdbserver.
This does mean adding back some non-shared code when this whole series
has been about sharing code, but now the only non-shared bit is the
single line that is actually different between GDB and gdbserver, all
the rest, which is identical, is now shared.
I did need to add a new rule to the gdbserver Makefile, this is to
allow the nat/x86-linux-tdesc.c file to be compiled for the IPA.
Approved-By: John Baldwin <jhb@FreeBSD.org>
This commit is part of a series to share more of the x86 target
description creation code between GDB and gdbserver.
Unlike previous commits which were mostly refactoring, this commit is
the first that makes a real change, though that change should mostly
be for gdbserver; I've largely adopted the "GDB" way of doing things
for gdbserver, and this fixes a real gdbserver bug.
On a x86-64 Linux target, running the test:
gdb.server/connect-with-no-symbol-file.exp
results in two core files being created. Both of these core files are
from the inferior process, created after gdbserver has detached.
In this test a gdbserver process is started and then, after gdbserver
has started, but before GDB attaches, we either delete the inferior
executable, or change its permissions so it can't be read. Only after
doing this do we attempt to connect with GDB.
As GDB connects to gdbserver, gdbserver attempts to figure out the
target description so that it can send the description to GDB, this
involves a call to x86_linux_read_description.
In x86_linux_read_description one of the first things we do is try to
figure out if the process is 32-bit or 64-bit. To do this we look up
the executable via the thread-id, and then attempt to read the
architecture size from the executable. This isn't going to work if
the executable has been deleted, or is no longer readable.
And so, as we can't read the executable, we default to an i386 target
and use an i386 target description.
A consequence of using an i386 target description is that addresses
are assumed to be 32-bits. Here's an example session that shows the
problems this causes. This is run on an x86-64 machine, and the test
binary (xx.x) is a standard 64-bit x86-64 binary:
shell_1$ gdbserver --once localhost :54321 /tmp/xx.x
shell_2$ gdb -q
(gdb) set sysroot
(gdb) shell chmod 000 /tmp/xx.x
(gdb) target remote :54321
Remote debugging using :54321
warning: /tmp/xx.x: Permission denied.
0xf7fd3110 in ?? ()
(gdb) show architecture
The target architecture is set to "auto" (currently "i386").
(gdb) p/x $pc
$1 = 0xf7fd3110
(gdb) info proc mappings
process 2412639
Mapped address spaces:
Start Addr End Addr Size Offset Perms objfile
0x400000 0x401000 0x1000 0x0 r--p /tmp/xx.x
0x401000 0x402000 0x1000 0x1000 r-xp /tmp/xx.x
0x402000 0x403000 0x1000 0x2000 r--p /tmp/xx.x
0x403000 0x405000 0x2000 0x2000 rw-p /tmp/xx.x
0xf7fcb000 0xf7fcf000 0x4000 0x0 r--p [vvar]
0xf7fcf000 0xf7fd1000 0x2000 0x0 r-xp [vdso]
0xf7fd1000 0xf7fd3000 0x2000 0x0 r--p /usr/lib64/ld-2.30.so
0xf7fd3000 0xf7ff3000 0x20000 0x2000 r-xp /usr/lib64/ld-2.30.so
0xf7ff3000 0xf7ffb000 0x8000 0x22000 r--p /usr/lib64/ld-2.30.so
0xf7ffc000 0xf7ffe000 0x2000 0x2a000 rw-p /usr/lib64/ld-2.30.so
0xf7ffe000 0xf7fff000 0x1000 0x0 rw-p
0xfffda000 0xfffff000 0x25000 0x0 rw-p [stack]
0xff600000 0xff601000 0x1000 0x0 r-xp [vsyscall]
(gdb) info inferiors
Num Description Connection Executable
* 1 process 2412639 1 (remote :54321)
(gdb) shell cat /proc/2412639/maps
00400000-00401000 r--p 00000000 fd:03 45907133 /tmp/xx.x
00401000-00402000 r-xp 00001000 fd:03 45907133 /tmp/xx.x
00402000-00403000 r--p 00002000 fd:03 45907133 /tmp/xx.x
00403000-00405000 rw-p 00002000 fd:03 45907133 /tmp/xx.x
7ffff7fcb000-7ffff7fcf000 r--p 00000000 00:00 0 [vvar]
7ffff7fcf000-7ffff7fd1000 r-xp 00000000 00:00 0 [vdso]
7ffff7fd1000-7ffff7fd3000 r--p 00000000 fd:00 143904 /usr/lib64/ld-2.30.so
7ffff7fd3000-7ffff7ff3000 r-xp 00002000 fd:00 143904 /usr/lib64/ld-2.30.so
7ffff7ff3000-7ffff7ffb000 r--p 00022000 fd:00 143904 /usr/lib64/ld-2.30.so
7ffff7ffc000-7ffff7ffe000 rw-p 0002a000 fd:00 143904 /usr/lib64/ld-2.30.so
7ffff7ffe000-7ffff7fff000 rw-p 00000000 00:00 0
7ffffffda000-7ffffffff000 rw-p 00000000 00:00 0 [stack]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
(gdb)
Notice the difference between the mappings reported via GDB and those
reported directly from the kernel via /proc/PID/maps, the addresses of
every mapping is clamped to 32-bits for GDB, while the kernel reports
real 64-bit addresses.
Notice also that the $pc value is a 32-bit value. It appears to be
within one of the mappings reported by GDB, but is outside any of the
mappings reported from the kernel.
And this is where the problem arises. When gdbserver detaches from
the inferior we pass the inferior the address from which it should
resume. Due to the 32/64 bit confusion we tell the inferior to resume
from the 32-bit $pc value, which is not within any valid mapping, and
so, as soon as the inferior resumes, it segfaults.
If we look at how GDB (not gdbserver) figures out its target
description then we see an interesting difference. GDB doesn't try to
read the executable. Instead GDB uses ptrace to query the thread's
state, and uses this to figure out the if the thread is 32 or 64 bit.
If we update gdbserver to do it the "GDB" way then the above problem
is resolved, gdbserver now sees the process as 64-bit, and when we
detach from the inferior we give it the correct 64-bit address, and
the inferior no longer segfaults.
Now, I could just update the gdbserver code, but better, I think, to
share one copy of the code between GDB and gdbserver in gdb/nat/.
That is what this commit does.
The cores of x86_linux_read_description from gdbserver and
x86_linux_nat_target::read_description from GDB are moved into a new
file gdb/nat/x86-linux-tdesc.c and combined into a single function
x86_linux_tdesc_for_tid which is called from each location.
This new function does things the GDB way, the only changes are to
allow for the sharing; we now have a callback function to call the
first time that the xcr0 state is read, this allows for GDB and
gdbserver to perform their own initialisation as needed, and
additionally, the new function takes a pointer for where to cache the
xcr0 value, this isn't needed for this commit, but will be useful in a
later commit where gdbserver will want to read this cached xcr0
value.
Another thing to note about this commit is how the functions
i386_linux_read_description and amd64_linux_read_description are
handled. For now I've left these function as implemented separately
in GDB and gdbserver. I've moved the declarations of these functions
into gdb/nat/x86-linux-tdesc.h, but the implementations are left as
separate.
A later commit in this series will make these functions shared too,
but doing this is not trivial, so I've left that for a separate
commit. Merging the declarations as I've done here ensures that
everyone implements the function to the same API, and once these
functions are shared (in a later commit) we'll want a shared
declaration anyway.
Approved-By: John Baldwin <jhb@FreeBSD.org>
Share the definition of I386_LINUX_XSAVE_XCR0_OFFSET between GDB and
gdbserver.
This commit is part of a series that aims to share more of the x86
target description creation code between GDB and gdbserver. The
I386_LINUX_XSAVE_XCR0_OFFSET #define is used as part of the target
description creation, and I noticed that this constant is defined
separately for GDB and gdbserver.
This commit moves the definition into gdb/nat/x86-linux.h, which
allows the #define to be shared.
There should be no user visible changes after this commit.
Approved-By: John Baldwin <jhb@FreeBSD.org>
We currently pass frames to function by value, as `frame_info_ptr`.
This is somewhat expensive:
- the size of `frame_info_ptr` is 64 bytes, which is a bit big to pass
by value
- the constructors and destructor link/unlink the object in the global
`frame_info_ptr::frame_list` list. This is an `intrusive_list`, so
it's not so bad: it's just assigning a few points, there's no memory
allocation as if it was `std::list`, but still it's useless to do
that over and over.
As suggested by Tom Tromey, change many function signatures to accept
`const frame_info_ptr &` instead of `frame_info_ptr`.
Some functions reassign their `frame_info_ptr` parameter, like:
void
the_func (frame_info_ptr frame)
{
for (; frame != nullptr; frame = get_prev_frame (frame))
{
...
}
}
I wondered what to do about them, do I leave them as-is or change them
(and need to introduce a separate local variable that can be
re-assigned). I opted for the later for consistency. It might not be
clear why some functions take `const frame_info_ptr &` while others take
`frame_info_ptr`. Also, if a function took a `frame_info_ptr` because
it did re-assign its parameter, I doubt that we would think to change it
to `const frame_info_ptr &` should the implementation change such that
it doesn't need to take `frame_info_ptr` anymore. It seems better to
have a simple rule and apply it everywhere.
Change-Id: I59d10addef687d157f82ccf4d54f5dde9a963fd0
Approved-By: Andrew Burgess <aburgess@redhat.com>
This commit is the result of the following actions:
- Running gdb/copyright.py to update all of the copyright headers to
include 2024,
- Manually updating a few files the copyright.py script told me to
update, these files had copyright headers embedded within the
file,
- Regenerating gdbsupport/Makefile.in to refresh it's copyright
date,
- Using grep to find other files that still mentioned 2023. If
these files were updated last year from 2022 to 2023 then I've
updated them this year to 2024.
I'm sure I've probably missed some dates. Feel free to fix them up as
you spot them.
Refactor i386_linux_core_read_xcr0 to fetch and return a corresponding
x86_xsave_layout as well as xcr0 using the size of an existing
NT_X86_XSTATE core dump to determine the offsets via
i387_guess_xsave_layout. Use this to add an implementation of
gdbarch_core_xfer_x86_xsave_layout.
Use tdep->xsave_layout.sizeof_xsave as the size of the XSTATE register
set.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
These registers can be changed directly in userspace, and similar
registers to support TLS on other architectures (tpidr* on ARM and
AArch64, tp on RISC-V) are treated as general purpose registers.
Reviewed-By: Tom Tromey <tom@tromey.com>
This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
This changes GDB to use frame_info_ptr instead of frame_info *
The substitution was done with multiple sequential `sed` commands:
sed 's/^struct frame_info;/class frame_info_ptr;/'
sed 's/struct frame_info \*/frame_info_ptr /g' - which left some
issues in a few files, that were manually fixed.
sed 's/\<frame_info \*/frame_info_ptr /g'
sed 's/frame_info_ptr $/frame_info_ptr/g' - used to remove whitespace
problems.
The changed files were then manually checked and some 'sed' changes
undone, some constructors and some gets were added, according to what
made sense, and what Tromey originally did
Co-Authored-By: Bruno Larsen <blarsen@redhat.com>
Approved-by: Tom Tomey <tom@tromey.com>
I built GDB for all targets on a x86-64/GNU-Linux system, and
then (accidentally) passed GDB a RISC-V binary, and asked GDB to "run"
the binary on the native target. I got this error:
(gdb) show architecture
The target architecture is set to "auto" (currently "i386").
(gdb) file /tmp/hello.rv32.exe
Reading symbols from /tmp/hello.rv32.exe...
(gdb) show architecture
The target architecture is set to "auto" (currently "riscv:rv32").
(gdb) run
Starting program: /tmp/hello.rv32.exe
../../src/gdb/i387-tdep.c:596: internal-error: i387_supply_fxsave: Assertion `tdep->st0_regnum >= I386_ST0_REGNUM' failed.
What's going on here is this; initially the architecture is i386, this
is based on the default architecture, which is set based on the native
target. After loading the RISC-V executable the architecture of the
current inferior is updated based on the architecture of the
executable.
When we "run", GDB does a fork & exec, with the inferior being
controlled through ptrace. GDB sees an initial stop from the inferior
as soon as the inferior comes to life. In response to this stop GDB
ends up calling save_stop_reason (linux-nat.c), which ends up trying
to read register from the inferior, to do this we end up calling
target_ops::fetch_registers, which, for the x86-64 native target,
calls amd64_linux_nat_target::fetch_registers.
After this I eventually end up in i387_supply_fxsave, different x86
based targets will end in different functions to fetch registers, but
it doesn't really matter which function we end up in, the problem is
this line, which is repeated in many places:
i386_gdbarch_tdep *tdep = (i386_gdbarch_tdep *) gdbarch_tdep (arch);
The problem here is that the ARCH in this line comes from the current
inferior, which, as we discussed above, will be a RISC-V gdbarch, the
tdep field will actually be of type riscv_gdbarch_tdep, not
i386_gdbarch_tdep. After this cast we are relying on undefined
behaviour, in my case I happen to trigger an assert, but this might
not always be the case.
The thing I tried that exposed this problem was of course, trying to
start an executable of the wrong architecture on a native target. I
don't think that the correct solution for this problem is to detect,
at the point of cast, that the gdbarch_tdep object is of the wrong
type, but, I did wonder, is there a way that we could protect
ourselves from incorrectly casting the gdbarch_tdep object?
I think that there is something we can do here, and this commit is the
first step in that direction, though no actual check is added by this
commit.
This commit can be split into two parts:
(1) In gdbarch.h and arch-utils.c. In these files I have modified
gdbarch_tdep (the function) so that it now takes a template argument,
like this:
template<typename TDepType>
static inline TDepType *
gdbarch_tdep (struct gdbarch *gdbarch)
{
struct gdbarch_tdep *tdep = gdbarch_tdep_1 (gdbarch);
return static_cast<TDepType *> (tdep);
}
After this change we are no better protected, but the cast is now
done within the gdbarch_tdep function rather than at the call sites,
this leads to the second, much larger change in this commit,
(2) Everywhere gdbarch_tdep is called, we make changes like this:
- i386_gdbarch_tdep *tdep = (i386_gdbarch_tdep *) gdbarch_tdep (arch);
+ i386_gdbarch_tdep *tdep = gdbarch_tdep<i386_gdbarch_tdep> (arch);
There should be no functional change after this commit.
In the next commit I will build on this change to add an assertion in
gdbarch_tdep that checks we are casting to the correct type.
When running test-case gdb.reverse/pipe-reverse.exp on openSUSE Tumbleweed,
I run into:
...
(gdb) continue^M
Continuing.^M
Process record and replay target doesn't support syscall number 293^M
Process record: failed to record execution log.^M
^M
Program stopped.^M
0x00007ffff7daabdb in pipe () from /lib64/libc.so.6^M
(gdb) FAIL: gdb.reverse/pipe-reverse.exp: continue to breakpoint: marker2
...
The current glibc on Tumbleweed is 2.35, which contains commit
"linux: Implement pipe in terms of __NR_pipe2", and consequently syscall pipe2
is used in stead of syscall pipe.
There is already support added for syscall pipe2 for aarch64 (which only has
syscall pipe2, not syscall pipe), so enable the same for amd64, by:
- adding amd64_sys_pipe2 in enum amd64_syscall
- translating amd64_sys_pipe2 to gdb_sys_pipe2 in amd64_canonicalize_syscall
Tested on x86_64-linux, specifically on:
- openSUSE Tumbleweed (with glibc 2.35), and
- openSUSE Leap 15.3 (with glibc 2.31).
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29056
Change gdbarch_register_reggroup_p to take a 'const struct reggroup *'
argument. This requires a change to the gdb/gdbarch-components.py
script, regeneration of gdbarch.{c,h}, and then updates to all the
architectures that implement this method.
There should be no user visible changes after this commit.
1. Since 32bit-pkeys.xml and 64bit-pkeys.xml are identical, consolidate
them into a single keys.xml.
2. Enable PKU for x32 to fix:
$ gdbserver :123456 x32-program
...
.../gdbserver/regcache.cc:255: A problem internal to GDBserver has been detected
.
Unknown register pkru requested
on Tiger Lake.
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.
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 process record code often emits unfiltered output. In some cases,
this output ought to go to gdb_stderr (but see below). In other
cases, the output is guarded by a logging variable and so ought to go
to gdb_stdlog. This patch makes these changes.
Note that in many cases, the output to stderr is followed by a
"return -1", which is how process record indicates an error. It seems
to me that calling error here would be preferable, because, in many
cases, that's all the caller does when it sees a -1. However, I
haven't made this change.
This is part of PR gdb/7233.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=7233
I think it would make sense for extract_integer, extract_signed_integer
and extract_unsigned_integer to take an array_view. This way, when we
extract an integer, we can validate that we don't overflow the buffer
passed by the caller (e.g. ask to extract a 4-byte integer but pass a
2-byte buffer).
- Change extract_integer to take an array_view
- Add overloads of extract_signed_integer and extract_unsigned_integer
that take array_views. Keep the existing versions so we don't
need to change all callers, but make them call the array_view
versions.
This shortens some places like:
result = extract_unsigned_integer (value_contents (result_val).data (),
TYPE_LENGTH (value_type (result_val)),
byte_order);
into
result = extract_unsigned_integer (value_contents (result_val), byte_order);
value_contents returns an array view that is of length
`TYPE_LENGTH (value_type (result_val))` already, so the length is
implicitly communicated through the array view.
Change-Id: Ic1c1f98c88d5c17a8486393af316f982604d6c95
I would like to be able to use non-trivial types in gdbarch_tdep types.
This is not possible at the moment (in theory), because of the one
definition rule.
To allow it, rename all gdbarch_tdep types to <arch>_gdbarch_tdep, and
make them inherit from a gdbarch_tdep base class. The inheritance is
necessary to be able to pass pointers to all these <arch>_gdbarch_tdep
objects to gdbarch_alloc, which takes a pointer to gdbarch_tdep.
These objects are never deleted through a base class pointer, so I
didn't include a virtual destructor. In the future, if gdbarch objects
deletable, I could imagine that the gdbarch_tdep objects could become
owned by the gdbarch objects, and then it would become useful to have a
virtual destructor (so that the gdbarch object can delete the owned
gdbarch_tdep object). But that's not necessary right now.
It turns out that RISC-V already has a gdbarch_tdep that is
non-default-constructible, so that provides a good motivation for this
change.
Most changes are fairly straightforward, mostly needing to add some
casts all over the place. There is however the xtensa architecture,
doing its own little weird thing to define its gdbarch_tdep. I did my
best to adapt it, but I can't test those changes.
Change-Id: Ic001903f91ddd106bd6ca09a79dabe8df2d69f3b
The r_ldsomap field is specific to Solaris (part of librtld_db), and
should never be accessed for Linux. glibc is planning to add a field
to support multiple namespaces. But there will be no r_ldsomap when
r_version is bumped to 2. Add linux_[ilp32|lp64]_fetch_link_map_offsets
to set r_ldsomap_offset to -1 and use them for Linux targets.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28236
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
As observed on a binary compiled on AMD64 Ubuntu 20.04, against glibc
2.31 (I think it's the libc that provides this startup code, right?),
there are enough bytes at the executable's entry point to hold more than
one displaced step buffer. gdbarch_max_insn_length is 16, and the
code at _start looks like:
0000000000001040 <_start>:
1040: f3 0f 1e fa endbr64
1044: 31 ed xor %ebp,%ebp
1046: 49 89 d1 mov %rdx,%r9
1049: 5e pop %rsi
104a: 48 89 e2 mov %rsp,%rdx
104d: 48 83 e4 f0 and $0xfffffffffffffff0,%rsp
1051: 50 push %rax
1052: 54 push %rsp
1053: 4c 8d 05 56 01 00 00 lea 0x156(%rip),%r8 # 11b0 <__libc_csu_fini>
105a: 48 8d 0d df 00 00 00 lea 0xdf(%rip),%rcx # 1140 <__libc_csu_init>
1061: 48 8d 3d c1 00 00 00 lea 0xc1(%rip),%rdi # 1129 <main>
1068: ff 15 72 2f 00 00 callq *0x2f72(%rip) # 3fe0 <__libc_start_main@GLIBC_2.2.5>
106e: f4 hlt
106f: 90 nop
The two buffers would occupy [0x1040, 0x1060).
I checked on Alpine, which uses the musl C library, the startup code
looks like:
0000000000001048 <_start>:
1048: 48 31 ed xor %rbp,%rbp
104b: 48 89 e7 mov %rsp,%rdi
104e: 48 8d 35 e3 2d 00 00 lea 0x2de3(%rip),%rsi # 3e38 <_DYNAMIC>
1055: 48 83 e4 f0 and $0xfffffffffffffff0,%rsp
1059: e8 00 00 00 00 callq 105e <_start_c>
000000000000105e <_start_c>:
105e: 48 8b 37 mov (%rdi),%rsi
1061: 48 8d 57 08 lea 0x8(%rdi),%rdx
1065: 45 31 c9 xor %r9d,%r9d
1068: 4c 8d 05 47 01 00 00 lea 0x147(%rip),%r8 # 11b6 <_fini>
106f: 48 8d 0d 8a ff ff ff lea -0x76(%rip),%rcx # 1000 <_init>
1076: 48 8d 3d 0c 01 00 00 lea 0x10c(%rip),%rdi # 1189 <main>
107d: e9 9e ff ff ff jmpq 1020 <__libc_start_main@plt>
Even though there's a _start_c symbol, it all appears to be code that
runs once at the very beginning of the program, so it looks fine if the
two buffers occupy [0x1048, 0x1068).
One important thing I discovered while doing this is that when debugging
a dynamically-linked executable, breakpoints in the shared library
loader are hit before executing the _start code, and these breakpoints
may be displaced-stepped. So it's very important that the buffer bytes
are restored properly after doing the displaced steps, otherwise the
_start code will be corrupted once we try to execute it.
Another thing that made me think about is that library constructors (as
in `__attribute__((constructor))`) run before _start. And they are free
to spawn threads. What if one of these threads executes a displaced
step, therefore changing the bytes at _start, while the main thread
executes _start? That doesn't sound good and I don't know how we could
prevent it. But this is a problem that predates the current patch.
Even when stress-testing the implementation, by making many threads do
displaced steps over and over, I didn't see a significant performance (I
confirmed that the two buffers were used by checking the "set debug
displaced" logs though). However, this patch mostly helps make the
feature testable by anybody with an AMD64/Linux machine, so I think it's
useful.
gdb/ChangeLog:
* amd64-linux-tdep.c (amd64_linux_init_abi): Pass 2 as the
number of displaced step buffers.
Change-Id: Ia0c96ea0fcda893f4726df6fdac7be5214620112
Today, GDB only allows a single displaced stepping operation to happen
per inferior at a time. There is a single displaced stepping buffer per
inferior, whose address is fixed (obtained with
gdbarch_displaced_step_location), managed by infrun.c.
In the case of the AMD ROCm target [1] (in the context of which this
work has been done), it is typical to have thousands of threads (or
waves, in SMT terminology) executing the same code, hitting the same
breakpoint (possibly conditional) and needing to to displaced step it at
the same time. The limitation of only one displaced step executing at a
any given time becomes a real bottleneck.
To fix this bottleneck, we want to make it possible for threads of a
same inferior to execute multiple displaced steps in parallel. This
patch builds the foundation for that.
In essence, this patch moves the task of preparing a displaced step and
cleaning up after to gdbarch functions. This allows using different
schemes for allocating and managing displaced stepping buffers for
different platforms. The gdbarch decides how to assign a buffer to a
thread that needs to execute a displaced step.
On the ROCm target, we are able to allocate one displaced stepping
buffer per thread, so a thread will never have to wait to execute a
displaced step.
On Linux, the entry point of the executable if used as the displaced
stepping buffer, since we assume that this code won't get used after
startup. From what I saw (I checked with a binary generated against
glibc and musl), on AMD64 we have enough space there to fit two
displaced stepping buffers. A subsequent patch makes AMD64/Linux use
two buffers.
In addition to having multiple displaced stepping buffers, there is also
the idea of sharing displaced stepping buffers between threads. Two
threads doing displaced steps for the same PC could use the same buffer
at the same time. Two threads stepping over the same instruction (same
opcode) at two different PCs may also be able to share a displaced
stepping buffer. This is an idea for future patches, but the
architecture built by this patch is made to allow this.
Now, the implementation details. The main part of this patch is moving
the responsibility of preparing and finishing a displaced step to the
gdbarch. Before this patch, preparing a displaced step is driven by the
displaced_step_prepare_throw function. It does some calls to the
gdbarch to do some low-level operations, but the high-level logic is
there. The steps are roughly:
- Ask the gdbarch for the displaced step buffer location
- Save the existing bytes in the displaced step buffer
- Ask the gdbarch to copy the instruction into the displaced step buffer
- Set the pc of the thread to the beginning of the displaced step buffer
Similarly, the "fixup" phase, executed after the instruction was
successfully single-stepped, is driven by the infrun code (function
displaced_step_finish). The steps are roughly:
- Restore the original bytes in the displaced stepping buffer
- Ask the gdbarch to fixup the instruction result (adjust the target's
registers or memory to do as if the instruction had been executed in
its original location)
The displaced_step_inferior_state::step_thread field indicates which
thread (if any) is currently using the displaced stepping buffer, so it
is used by displaced_step_prepare_throw to check if the displaced
stepping buffer is free to use or not.
This patch defers the whole task of preparing and cleaning up after a
displaced step to the gdbarch. Two new main gdbarch methods are added,
with the following semantics:
- gdbarch_displaced_step_prepare: Prepare for the given thread to
execute a displaced step of the instruction located at its current PC.
Upon return, everything should be ready for GDB to resume the thread
(with either a single step or continue, as indicated by
gdbarch_displaced_step_hw_singlestep) to make it displaced step the
instruction.
- gdbarch_displaced_step_finish: Called when the thread stopped after
having started a displaced step. Verify if the instruction was
executed, if so apply any fixup required to compensate for the fact
that the instruction was executed at a different place than its
original pc. Release any resources that were allocated for this
displaced step. Upon return, everything should be ready for GDB to
resume the thread in its "normal" code path.
The displaced_step_prepare_throw function now pretty much just offloads
to gdbarch_displaced_step_prepare and the displaced_step_finish function
offloads to gdbarch_displaced_step_finish.
The gdbarch_displaced_step_location method is now unnecessary, so is
removed. Indeed, the core of GDB doesn't know how many displaced step
buffers there are nor where they are.
To keep the existing behavior for existing architectures, the logic that
was previously implemented in infrun.c for preparing and finishing a
displaced step is moved to displaced-stepping.c, to the
displaced_step_buffer class. Architectures are modified to implement
the new gdbarch methods using this class. The behavior is not expected
to change.
The other important change (which arises from the above) is that the
core of GDB no longer prevents concurrent displaced steps. Before this
patch, start_step_over walks the global step over chain and tries to
initiate a step over (whether it is in-line or displaced). It follows
these rules:
- if an in-line step is in progress (in any inferior), don't start any
other step over
- if a displaced step is in progress for an inferior, don't start
another displaced step for that inferior
After starting a displaced step for a given inferior, it won't start
another displaced step for that inferior.
In the new code, start_step_over simply tries to initiate step overs for
all the threads in the list. But because threads may be added back to
the global list as it iterates the global list, trying to initiate step
overs, start_step_over now starts by stealing the global queue into a
local queue and iterates on the local queue. In the typical case, each
thread will either:
- have initiated a displaced step and be resumed
- have been added back by the global step over queue by
displaced_step_prepare_throw, because the gdbarch will have returned
that there aren't enough resources (i.e. buffers) to initiate a
displaced step for that thread
Lastly, if start_step_over initiates an in-line step, it stops
iterating, and moves back whatever remaining threads it had in its local
step over queue to the global step over queue.
Two other gdbarch methods are added, to handle some slightly annoying
corner cases. They feel awkwardly specific to these cases, but I don't
see any way around them:
- gdbarch_displaced_step_copy_insn_closure_by_addr: in
arm_pc_is_thumb, arm-tdep.c wants to get the closure for a given
buffer address.
- gdbarch_displaced_step_restore_all_in_ptid: when a process forks
(at least on Linux), the address space is copied. If some displaced
step buffers were in use at the time of the fork, we need to restore
the original bytes in the child's address space.
These two adjustments are also made in infrun.c:
- prepare_for_detach: there may be multiple threads doing displaced
steps when we detach, so wait until all of them are done
- handle_inferior_event: when we handle a fork event for a given
thread, it's possible that other threads are doing a displaced step at
the same time. Make sure to restore the displaced step buffer
contents in the child for them.
[1] https://github.com/ROCm-Developer-Tools/ROCgdb
gdb/ChangeLog:
* displaced-stepping.h (struct
displaced_step_copy_insn_closure): Adjust comments.
(struct displaced_step_inferior_state) <step_thread,
step_gdbarch, step_closure, step_original, step_copy,
step_saved_copy>: Remove fields.
(struct displaced_step_thread_state): New.
(struct displaced_step_buffer): New.
* displaced-stepping.c (displaced_step_buffer::prepare): New.
(write_memory_ptid): Move from infrun.c.
(displaced_step_instruction_executed_successfully): New,
factored out of displaced_step_finish.
(displaced_step_buffer::finish): New.
(displaced_step_buffer::copy_insn_closure_by_addr): New.
(displaced_step_buffer::restore_in_ptid): New.
* gdbarch.sh (displaced_step_location): Remove.
(displaced_step_prepare, displaced_step_finish,
displaced_step_copy_insn_closure_by_addr,
displaced_step_restore_all_in_ptid): New.
* gdbarch.c: Re-generate.
* gdbarch.h: Re-generate.
* gdbthread.h (class thread_info) <displaced_step_state>: New
field.
(thread_step_over_chain_remove): New declaration.
(thread_step_over_chain_next): New declaration.
(thread_step_over_chain_length): New declaration.
* thread.c (thread_step_over_chain_remove): Make non-static.
(thread_step_over_chain_next): New.
(global_thread_step_over_chain_next): Use
thread_step_over_chain_next.
(thread_step_over_chain_length): New.
(global_thread_step_over_chain_enqueue): Add debug print.
(global_thread_step_over_chain_remove): Add debug print.
* infrun.h (get_displaced_step_copy_insn_closure_by_addr):
Remove.
* infrun.c (get_displaced_stepping_state): New.
(displaced_step_in_progress_any_inferior): Remove.
(displaced_step_in_progress_thread): Adjust.
(displaced_step_in_progress): Adjust.
(displaced_step_in_progress_any_thread): New.
(get_displaced_step_copy_insn_closure_by_addr): Remove.
(gdbarch_supports_displaced_stepping): Use
gdbarch_displaced_step_prepare_p.
(displaced_step_reset): Change parameter from inferior to
thread.
(displaced_step_prepare_throw): Implement using
gdbarch_displaced_step_prepare.
(write_memory_ptid): Move to displaced-step.c.
(displaced_step_restore): Remove.
(displaced_step_finish): Implement using
gdbarch_displaced_step_finish.
(start_step_over): Allow starting more than one displaced step.
(prepare_for_detach): Handle possibly multiple threads doing
displaced steps.
(handle_inferior_event): Handle possibility that fork event
happens while another thread displaced steps.
* linux-tdep.h (linux_displaced_step_prepare): New.
(linux_displaced_step_finish): New.
(linux_displaced_step_copy_insn_closure_by_addr): New.
(linux_displaced_step_restore_all_in_ptid): New.
(linux_init_abi): Add supports_displaced_step parameter.
* linux-tdep.c (struct linux_info) <disp_step_buf>: New field.
(linux_displaced_step_prepare): New.
(linux_displaced_step_finish): New.
(linux_displaced_step_copy_insn_closure_by_addr): New.
(linux_displaced_step_restore_all_in_ptid): New.
(linux_init_abi): Add supports_displaced_step parameter,
register displaced step methods if true.
(_initialize_linux_tdep): Register inferior_execd observer.
* amd64-linux-tdep.c (amd64_linux_init_abi_common): Add
supports_displaced_step parameter, adjust call to
linux_init_abi. Remove call to
set_gdbarch_displaced_step_location.
(amd64_linux_init_abi): Adjust call to
amd64_linux_init_abi_common.
(amd64_x32_linux_init_abi): Likewise.
* aarch64-linux-tdep.c (aarch64_linux_init_abi): Adjust call to
linux_init_abi. Remove call to
set_gdbarch_displaced_step_location.
* arm-linux-tdep.c (arm_linux_init_abi): Likewise.
* i386-linux-tdep.c (i386_linux_init_abi): Likewise.
* alpha-linux-tdep.c (alpha_linux_init_abi): Adjust call to
linux_init_abi.
* arc-linux-tdep.c (arc_linux_init_osabi): Likewise.
* bfin-linux-tdep.c (bfin_linux_init_abi): Likewise.
* cris-linux-tdep.c (cris_linux_init_abi): Likewise.
* csky-linux-tdep.c (csky_linux_init_abi): Likewise.
* frv-linux-tdep.c (frv_linux_init_abi): Likewise.
* hppa-linux-tdep.c (hppa_linux_init_abi): Likewise.
* ia64-linux-tdep.c (ia64_linux_init_abi): Likewise.
* m32r-linux-tdep.c (m32r_linux_init_abi): Likewise.
* m68k-linux-tdep.c (m68k_linux_init_abi): Likewise.
* microblaze-linux-tdep.c (microblaze_linux_init_abi): Likewise.
* mips-linux-tdep.c (mips_linux_init_abi): Likewise.
* mn10300-linux-tdep.c (am33_linux_init_osabi): Likewise.
* nios2-linux-tdep.c (nios2_linux_init_abi): Likewise.
* or1k-linux-tdep.c (or1k_linux_init_abi): Likewise.
* riscv-linux-tdep.c (riscv_linux_init_abi): Likewise.
* s390-linux-tdep.c (s390_linux_init_abi_any): Likewise.
* sh-linux-tdep.c (sh_linux_init_abi): Likewise.
* sparc-linux-tdep.c (sparc32_linux_init_abi): Likewise.
* sparc64-linux-tdep.c (sparc64_linux_init_abi): Likewise.
* tic6x-linux-tdep.c (tic6x_uclinux_init_abi): Likewise.
* tilegx-linux-tdep.c (tilegx_linux_init_abi): Likewise.
* xtensa-linux-tdep.c (xtensa_linux_init_abi): Likewise.
* ppc-linux-tdep.c (ppc_linux_init_abi): Adjust call to
linux_init_abi. Remove call to
set_gdbarch_displaced_step_location.
* arm-tdep.c (arm_pc_is_thumb): Call
gdbarch_displaced_step_copy_insn_closure_by_addr instead of
get_displaced_step_copy_insn_closure_by_addr.
* rs6000-aix-tdep.c (rs6000_aix_init_osabi): Adjust calls to
clear gdbarch methods.
* rs6000-tdep.c (struct ppc_inferior_data): New structure.
(get_ppc_per_inferior): New function.
(ppc_displaced_step_prepare): New function.
(ppc_displaced_step_finish): New function.
(ppc_displaced_step_restore_all_in_ptid): New function.
(rs6000_gdbarch_init): Register new gdbarch methods.
* s390-tdep.c (s390_gdbarch_init): Don't call
set_gdbarch_displaced_step_location, set new gdbarch methods.
gdb/testsuite/ChangeLog:
* gdb.arch/amd64-disp-step-avx.exp: Adjust pattern.
* gdb.threads/forking-threads-plus-breakpoint.exp: Likewise.
* gdb.threads/non-stop-fair-events.exp: Likewise.
Change-Id: I387cd235a442d0620ec43608fd3dc0097fcbf8c8
gdb/ChangeLog:
* amd64-linux-tdep.c (amd64_linux_init_abi_common): Use
i386_linux_report_signal_info instead of
i386_linux_handle_segmentation_fault.
* i386-linux-tdep.c (i386_linux_handle_segmentation_fault): Rename
to i386_linux_report_signal_info and add siggnal argument.
(i386_linux_init_abi): Use i386_linux_report_signal_info instead
of i386_linux_handle_segmentation_fault.
* i386-linux-tdep.h (i386_linux_handle_segmentation_fault): Rename
to i386_linux_report_signal_info and add siggnal argument.
Both the i386, X86_64 and AArch64 builds of gdbserver include a bunch of legacy
xml files, dat files and auto generated C files, when building for unit test.
These tests exists back from when feature target descriptions were added to
prove that the new target descriptions were identical to the original
older versions. The old files are not used for anything other than these tests.
Now that this has been proven, we are not gaining anything by keeping the
original files and tests. Should new functionality be added, it would break
the tests, unless the functionality was backported to the xml. There is no
requirement that we must match the exact xml from N releases ago. It adds
obfuscation, where as the feature target descriptions were meant to simplify
the code.
In addition, there are a bunch of xml and dat files which are completely unused.
This patch removes the selftests and the target descriptions from gdbserver.
Update the unittest to allow 0 tests (note, this failed on other targets that
never had any tests).
gdb/ChangeLog:
* aarch64-tdep.c: Remove xml self tests.
* amd64-linux-tdep.c: Likewise.
* amd64-tdep.c: Likewise.
* i386-linux-tdep.c: Likewise.
* i386-tdep.c: Likewise.
gdb/gdbserver/ChangeLog:
* configure.srv: Remove legacy xml.
* linux-aarch64-low.c (initialize_low_arch): Remove
initialize_low_tdesc call.
* linux-aarch64-tdesc-selftest.c: Remove file.
* linux-aarch64-tdesc.h (initialize_low_tdesc): Remove.
* linux-x86-low.c (initialize_low_arch): Remove
initialize_low_tdesc call.
* linux-x86-tdesc-selftest.c: Remove file.
* linux-x86-tdesc.h (initialize_low_tdesc): Remove.
gdb/testsuite/ChangeLog:
* gdb.server/unittest.exp: Allow 0 unit tests to run.
This makes a new base class, expr_builder, for parser_state. This
separates the state needed to construct an expression from the state
needed by the parsers.
gdb/ChangeLog
2019-04-04 Tom Tromey <tom@tromey.com>
* gdbarch.h, gdbarch.c: Rebuild.
* gdbarch.sh (dtrace_parse_probe_argument): Change type.
* stap-probe.h:
(struct stap_parse_info): Replace "parser_state" with
"expr_builder".
* parser-defs.h (struct expr_builder): Rename from "parser_state".
(parser_state): New class.
* parse.c (expr_builder): Rename.
(expr_builder::release): Rename.
(write_exp_elt, write_exp_elt_opcode, write_exp_elt_sym)
(write_exp_elt_msym, write_exp_elt_block, write_exp_elt_objfile)
(write_exp_elt_longcst, write_exp_elt_floatcst)
(write_exp_elt_type, write_exp_elt_intern, write_exp_string)
(write_exp_string_vector, write_exp_bitstring)
(write_exp_msymbol, mark_struct_expression)
(write_dollar_variable)
(insert_type_address_space, increase_expout_size): Replace
"parser_state" with "expr_builder".
* dtrace-probe.c: Replace "parser_state" with "expr_builder".
* amd64-linux-tdep.c (amd64_dtrace_parse_probe_argument): Replace
"parser_state" with "expr_builder".
This commit applies all changes made after running the gdb/copyright.py
script.
Note that one file was flagged by the script, due to an invalid
copyright header
(gdb/unittests/basic_string_view/element_access/char/empty.cc).
As the file was copied from GCC's libstdc++-v3 testsuite, this commit
leaves this file untouched for the time being; a patch to fix the header
was sent to gcc-patches first.
gdb/ChangeLog:
Update copyright year range in all GDB files.
In the existing code, when using the regset section iteration functions, the
size parameter is used in different ways.
With collect, size is used to create the buffer in which to write the regset.
(see linux-tdep.c::linux_collect_regset_section_cb).
With supply, size is used to confirm the existing regset is the correct size.
If REGSET_VARIABLE_SIZE is set then the regset can be bigger than size.
Effectively, size is the minimum possible size of the regset.
(see corelow.c::get_core_register_section).
There are currently no targets with both REGSET_VARIABLE_SIZE and a collect
function.
In SVE, a corefile can contain one of two formats after the header, both of
which are different sizes. However, when writing a core file, we always want
to write out the full bigger size.
To allow support of collects for REGSET_VARIABLE_SIZE we need two sizes.
This is done by adding supply_size and collect_size.
gdb/
* aarch64-fbsd-tdep.c
(aarch64_fbsd_iterate_over_regset_sections): Add supply_size and
collect_size.
* aarch64-linux-tdep.c
(aarch64_linux_iterate_over_regset_sections): Likewise.
* alpha-linux-tdep.c
(alpha_linux_iterate_over_regset_sections):
* alpha-nbsd-tdep.c
(alphanbsd_iterate_over_regset_sections): Likewise.
* amd64-fbsd-tdep.c
(amd64fbsd_iterate_over_regset_sections): Likewise.
* amd64-linux-tdep.c
(amd64_linux_iterate_over_regset_sections): Likewise.
* arm-bsd-tdep.c
(armbsd_iterate_over_regset_sections): Likewise.
* arm-fbsd-tdep.c
(arm_fbsd_iterate_over_regset_sections): Likewise.
* arm-linux-tdep.c
(arm_linux_iterate_over_regset_sections): Likewise.
* corelow.c (get_core_registers_cb): Likewise.
(core_target::fetch_registers): Likewise.
* fbsd-tdep.c (fbsd_collect_regset_section_cb): Likewise.
* frv-linux-tdep.c (frv_linux_iterate_over_regset_sections): Likewise.
* gdbarch.h (void): Regenerate.
* gdbarch.sh: Add supply_size and collect_size.
* hppa-linux-tdep.c (hppa_linux_iterate_over_regset_sections): Likewise.
* hppa-nbsd-tdep.c (hppanbsd_iterate_over_regset_sections): Likewise.
* hppa-obsd-tdep.c (hppaobsd_iterate_over_regset_sections): Likewise.
* i386-fbsd-tdep.c (i386fbsd_iterate_over_regset_sections): Likewise.
* i386-linux-tdep.c (i386_linux_iterate_over_regset_sections): Likewise.
* i386-tdep.c (i386_iterate_over_regset_sections): Likewise.
* ia64-linux-tdep.c (ia64_linux_iterate_over_regset_sections): Likewise.
* linux-tdep.c (linux_collect_regset_section_cb): Likewise.
* m32r-linux-tdep.c (m32r_linux_iterate_over_regset_sections): Likewise.
* m68k-bsd-tdep.c (m68kbsd_iterate_over_regset_sections): Likewise.
* m68k-linux-tdep.c (m68k_linux_iterate_over_regset_sections): Likewise.
* mips-fbsd-tdep.c (mips_fbsd_iterate_over_regset_sections): Likewise.
* mips-linux-tdep.c (mips_linux_iterate_over_regset_sections): Likewise.
* mips-nbsd-tdep.c (mipsnbsd_iterate_over_regset_sections): Likewise.
* mips64-obsd-tdep.c (mips64obsd_iterate_over_regset_sections): Likewise.
* mn10300-linux-tdep.c (am33_iterate_over_regset_sections): Likewise.
* nios2-linux-tdep.c (nios2_iterate_over_regset_sections): Likewise.
* ppc-fbsd-tdep.c (ppcfbsd_iterate_over_regset_sections): Likewise.
* ppc-linux-tdep.c (ppc_linux_iterate_over_regset_sections): Likewise.
* ppc-nbsd-tdep.c (ppcnbsd_iterate_over_regset_sections): Likewise.
* ppc-obsd-tdep.c (ppcobsd_iterate_over_regset_sections): Likewise.
* riscv-linux-tdep.c (riscv_linux_iterate_over_regset_sections): Likewise.
* rs6000-aix-tdep.c (rs6000_aix_iterate_over_regset_sections): Likewise.
* s390-linux-tdep.c (s390_iterate_over_regset_sections): Likewise.
* score-tdep.c (score7_linux_iterate_over_regset_sections): Likewise.
* sh-tdep.c (sh_iterate_over_regset_sections): Likewise.
* sparc-tdep.c (sparc_iterate_over_regset_sections): Likewise.
* tilegx-linux-tdep.c (tilegx_iterate_over_regset_sections): Likewise.
* vax-tdep.c (vax_iterate_over_regset_sections): Likewise.
* xtensa-tdep.c (xtensa_iterate_over_regset_sections): Likewise.
GDB is currently crashing anytime we try to access the fs_base/gs_base
registers, either to read them, or to write them. This can be observed
under various scenarios:
- Explicit reference to those registers (eg: print $fs_base) --
probably relatively rare;
- Calling a function in the inferior, with the crash happening
because we are trying to read those registers in order to save
their value ahead of making the function call;
- Just a plain "info registers";
The crash was introduced by the following commit:
| commit 48aeef91c2
| Date: Mon Jun 26 18:14:43 2017 -0700
| Subject: Include the fs_base and gs_base registers in amd64 target descriptions.
The Windows-nat implementation was unfortunately not prepared to deal
with those new registers. In particular, the way it fetches registers
is done by using a table where the index is the register number, and
the value at that index is the offset in the area in the thread's CONTEXT
data where the corresponding register value is stored.
For instance, in amd64-windows-nat.c, we can find the mappings static
array containing the following 57 elements in it:
#define context_offset(x) (offsetof (CONTEXT, x))
static const int mappings[] =
{
context_offset (Rax),
[...]
context_offset (FloatSave.MxCsr)
};
That array is then used by windows_fetch_one_register via:
char *context_offset = ((char *) &th->context) + mappings[r];
The problem is that fs_base's register number is 172, which is
well past the end of the mappings array (57 elements in total).
We end up getting an undefined offset, which happens to be so large
that it then causes the address where we try to read the register
value (a little bit later) to be invalid, thus crashing GDB with
a SEGV.
This patch side-steps the issue entirely by removing support for
those registers in GDB on x86_64-windows, because a look at the
CONTEXT structure indicates no support for getting those registers.
A more comprehensive fix would patch the potential buffer overflow
of the mappings array, but this can be done as a separate commit.
gdb/ChangeLog:
* gdb/amd64-tdep.h (amd64_create_target_description): Add
"segments" parameter.
* gdb/amd64-tdep.c (amd64_none_init_abi, amd64_x32_none_init_abi)
(_initialize_amd64_tdep): Update call to
amd64_create_target_description.
(amd64_target_description): Add "segments" parameter. Adjust
the implementation to use it.
* gdb/amd64-linux-tdep.c (amd64_linux_read_description): Update
call to amd64_create_target_description.
* gdb/amd64-windows-tdep.c (amd64_windows_init_abi): Likewise.
* gdb/arch/amd64.h (amd64_create_target_description): Add
"segments" register.
* gdb/arch/amd64.c (amd64_create_target_description): Add
"segments" parameter. Call create_feature_i386_64bit_segments
only if SEGMENTS is true.
* gdb/gdbserver/win32-i386-low.c (i386_arch_setup): Update
call to amd64_create_target_description.
Tested on x86_64-windows using AdaCore's testsuite (by Joel Brobecker
<brobecker at adacore dot com>).
This is more preparation bits for multi-target support.
In a multi-target scenario, we need to address the case of different
processes/threads running on different targets that happen to have the
same PID/PTID. E.g., we can have both process 123 in target 1, and
process 123 in target 2, while they're in reality different processes
running on different machines. Or maybe we've loaded multiple
instances of the same core file. Etc.
To address this, in my WIP multi-target branch, threads and processes
are uniquely identified by the (process_stratum target_ops *, ptid_t)
and (process_stratum target_ops *, pid) tuples respectively. I.e.,
each process_stratum instance has its own thread/process number space.
As you can imagine, that requires passing around target_ops * pointers
in a number of functions where we're currently passing only a ptid_t
or an int. E.g., when we look up a thread_info object by ptid_t in
find_thread_ptid, the ptid_t alone isn't sufficient.
In many cases though, we already have the thread_info or inferior
pointer handy, but we "lose" it somewhere along the call stack, only
to look it up again by ptid_t/pid. Since thread_info or inferior
objects know their parent target, if we pass around thread_info or
inferior pointers when possible, we avoid having to add extra
target_ops parameters to many functions, and also, we eliminate a
number of by ptid_t/int lookups.
So that's what this patch does. In a bit more detail:
- Changes a number of functions and methods to take a thread_info or
inferior pointer instead of a ptid_t or int parameter.
- Changes a number of structure fields from ptid_t/int to inferior or
thread_info pointers.
- Uses the inferior_thread() function whenever possible instead of
inferior_ptid.
- Uses thread_info pointers directly when possible instead of the
is_running/is_stopped etc. routines that require a lookup.
- A number of functions are eliminated along the way, such as:
int valid_gdb_inferior_id (int num);
int pid_to_gdb_inferior_id (int pid);
int gdb_inferior_id_to_pid (int num);
int in_inferior_list (int pid);
- A few structures and places hold a thread_info pointer across
inferior execution, so now they take a strong reference to the
(refcounted) thread_info object to avoid the thread_info pointer
getting stale. This is done in enable_thread_stack_temporaries and
in the infcall.c code.
- Related, there's a spot in infcall.c where using a RAII object to
handle the refcount would be handy, so a gdb::ref_ptr specialization
for thread_info is added (thread_info_ref, in gdbthread.h), along
with a gdb_ref_ptr policy that works for all refcounted_object types
(in common/refcounted-object.h).
gdb/ChangeLog:
2018-06-21 Pedro Alves <palves@redhat.com>
* ada-lang.h (ada_get_task_number): Take a thread_info pointer
instead of a ptid_t. All callers adjusted.
* ada-tasks.c (ada_get_task_number): Likewise. All callers
adjusted.
(print_ada_task_info, display_current_task_id, task_command_1):
Adjust.
* breakpoint.c (watchpoint_in_thread_scope): Adjust to use
inferior_thread.
(breakpoint_kind): Adjust.
(remove_breakpoints_pid): Rename to ...
(remove_breakpoints_inf): ... this. Adjust to take an inferior
pointer. All callers adjusted.
(bpstat_clear_actions): Use inferior_thread.
(get_bpstat_thread): New.
(bpstat_do_actions): Use it.
(bpstat_check_breakpoint_conditions, bpstat_stop_status): Adjust
to take a thread_info pointer. All callers adjusted.
(set_longjmp_breakpoint_for_call_dummy, set_momentary_breakpoint)
(breakpoint_re_set_thread): Use inferior_thread.
* breakpoint.h (struct inferior): Forward declare.
(bpstat_stop_status): Update.
(remove_breakpoints_pid): Delete.
(remove_breakpoints_inf): New.
* bsd-uthread.c (bsd_uthread_target::wait)
(bsd_uthread_target::update_thread_list): Use find_thread_ptid.
* btrace.c (btrace_add_pc, btrace_enable, btrace_fetch)
(maint_btrace_packet_history_cmd)
(maint_btrace_clear_packet_history_cmd): Adjust.
(maint_btrace_clear_cmd, maint_info_btrace_cmd): Adjust to use
inferior_thread.
* cli/cli-interp.c: Include "inferior.h".
* common/refcounted-object.h (struct
refcounted_object_ref_policy): New.
* compile/compile-object-load.c: Include gdbthread.h.
(store_regs): Use inferior_thread.
* corelow.c (core_target::close): Use current_inferior.
(core_target_open): Adjust to use first_thread_of_inferior and use
the current inferior.
* ctf.c (ctf_target::close): Adjust to use current_inferior.
* dummy-frame.c (dummy_frame_id) <ptid>: Delete, replaced by ...
<thread>: ... this new field. All references adjusted.
(dummy_frame_pop, dummy_frame_discard, register_dummy_frame_dtor):
Take a thread_info pointer instead of a ptid_t.
* dummy-frame.h (dummy_frame_push, dummy_frame_pop)
(dummy_frame_discard, register_dummy_frame_dtor): Take a
thread_info pointer instead of a ptid_t.
* elfread.c: Include "inferior.h".
(elf_gnu_ifunc_resolver_stop, elf_gnu_ifunc_resolver_return_stop):
Use inferior_thread.
* eval.c (evaluate_subexp): Likewise.
* frame.c (frame_pop, has_stack_frames, find_frame_sal): Use
inferior_thread.
* gdb_proc_service.h (struct thread_info): Forward declare.
(struct ps_prochandle) <ptid>: Delete, replaced by ...
<thread>: ... this new field. All references adjusted.
* gdbarch.h, gdbarch.c: Regenerate.
* gdbarch.sh (get_syscall_number): Replace 'ptid' parameter with a
'thread' parameter. All implementations and callers adjusted.
* gdbthread.h (thread_info) <set_running>: New method.
(delete_thread, delete_thread_silent): Take a thread_info pointer
instead of a ptid.
(global_thread_id_to_ptid, ptid_to_global_thread_id): Delete.
(first_thread_of_process): Delete, replaced by ...
(first_thread_of_inferior): ... this new function. All callers
adjusted.
(any_live_thread_of_process): Delete, replaced by ...
(any_live_thread_of_inferior): ... this new function. All callers
adjusted.
(switch_to_thread, switch_to_no_thread): Declare.
(is_executing): Delete.
(enable_thread_stack_temporaries): Update comment.
<enable_thread_stack_temporaries>: Take a thread_info pointer
instead of a ptid_t. Incref the thread.
<~enable_thread_stack_temporaries>: Decref the thread.
<m_ptid>: Delete
<m_thr>: New.
(thread_stack_temporaries_enabled_p, push_thread_stack_temporary)
(get_last_thread_stack_temporary)
(value_in_thread_stack_temporaries, can_access_registers_thread):
Take a thread_info pointer instead of a ptid_t. All callers
adjusted.
* infcall.c (get_call_return_value): Use inferior_thread.
(run_inferior_call): Work with thread pointers instead of ptid_t.
(call_function_by_hand_dummy): Work with thread pointers instead
of ptid_t. Use thread_info_ref.
* infcmd.c (proceed_thread_callback): Access thread's state
directly.
(ensure_valid_thread, ensure_not_running): Use inferior_thread,
access thread's state directly.
(continue_command): Use inferior_thread.
(info_program_command): Use find_thread_ptid and access thread
state directly.
(proceed_after_attach_callback): Use thread state directly.
(notice_new_inferior): Take a thread_info pointer instead of a
ptid_t. All callers adjusted.
(exit_inferior): Take an inferior pointer instead of a pid. All
callers adjusted.
(exit_inferior_silent): New.
(detach_inferior): Delete.
(valid_gdb_inferior_id, pid_to_gdb_inferior_id)
(gdb_inferior_id_to_pid, in_inferior_list): Delete.
(detach_inferior_command, kill_inferior_command): Use
find_inferior_id instead of valid_gdb_inferior_id and
gdb_inferior_id_to_pid.
(inferior_command): Use inferior and thread pointers.
* inferior.h (struct thread_info): Forward declare.
(notice_new_inferior): Take a thread_info pointer instead of a
ptid_t. All callers adjusted.
(detach_inferior): Delete declaration.
(exit_inferior, exit_inferior_silent): Take an inferior pointer
instead of a pid. All callers adjusted.
(gdb_inferior_id_to_pid, pid_to_gdb_inferior_id, in_inferior_list)
(valid_gdb_inferior_id): Delete.
* infrun.c (follow_fork_inferior, proceed_after_vfork_done)
(handle_vfork_child_exec_or_exit, follow_exec): Adjust.
(struct displaced_step_inferior_state) <pid>: Delete, replaced by
...
<inf>: ... this new field.
<step_ptid>: Delete, replaced by ...
<step_thread>: ... this new field.
(get_displaced_stepping_state): Take an inferior pointer instead
of a pid. All callers adjusted.
(displaced_step_in_progress_any_inferior): Adjust.
(displaced_step_in_progress_thread): Take a thread pointer instead
of a ptid_t. All callers adjusted.
(displaced_step_in_progress, add_displaced_stepping_state): Take
an inferior pointer instead of a pid. All callers adjusted.
(get_displaced_step_closure_by_addr): Adjust.
(remove_displaced_stepping_state): Take an inferior pointer
instead of a pid. All callers adjusted.
(displaced_step_prepare_throw, displaced_step_prepare)
(displaced_step_fixup): Take a thread pointer instead of a ptid_t.
All callers adjusted.
(start_step_over): Adjust.
(infrun_thread_ptid_changed): Remove bit updating ptids in the
displaced step queue.
(do_target_resume): Adjust.
(fetch_inferior_event): Use inferior_thread.
(context_switch, get_inferior_stop_soon): Take an
execution_control_state pointer instead of a ptid_t. All callers
adjusted.
(switch_to_thread_cleanup): Delete.
(stop_all_threads): Use scoped_restore_current_thread.
* inline-frame.c: Include "gdbthread.h".
(inline_state) <inline_state>: Take a thread pointer instead of a
ptid_t. All callers adjusted.
<ptid>: Delete, replaced by ...
<thread>: ... this new field.
(find_inline_frame_state): Take a thread pointer instead of a
ptid_t. All callers adjusted.
(skip_inline_frames, step_into_inline_frame)
(inline_skipped_frames, inline_skipped_symbol): Take a thread
pointer instead of a ptid_t. All callers adjusted.
* inline-frame.h (skip_inline_frames, step_into_inline_frame)
(inline_skipped_frames, inline_skipped_symbol): Likewise.
* linux-fork.c (delete_checkpoint_command): Adjust to use thread
pointers directly.
* linux-nat.c (get_detach_signal): Likewise.
* linux-thread-db.c (thread_from_lwp): New 'stopped' parameter.
(thread_db_notice_clone): Adjust.
(thread_db_find_new_threads_silently)
(thread_db_find_new_threads_2, thread_db_find_new_threads_1): Take
a thread pointer instead of a ptid_t. All callers adjusted.
* mi/mi-cmd-var.c: Include "inferior.h".
(mi_cmd_var_update_iter): Update to use thread pointers.
* mi/mi-interp.c (mi_new_thread): Update to use the thread's
inferior directly.
(mi_output_running_pid, mi_inferior_count): Delete, bits factored
out to ...
(mi_output_running): ... this new function.
(mi_on_resume_1): Adjust to use it.
(mi_user_selected_context_changed): Adjust to use inferior_thread.
* mi/mi-main.c (proceed_thread): Adjust to use thread pointers
directly.
(interrupt_thread_callback): : Adjust to use thread and inferior
pointers.
* proc-service.c: Include "gdbthread.h".
(ps_pglobal_lookup): Adjust to use the thread's inferior directly.
* progspace-and-thread.c: Include "inferior.h".
* progspace.c: Include "inferior.h".
* python/py-exitedevent.c (create_exited_event_object): Adjust to
hold a reference to an inferior_object.
* python/py-finishbreakpoint.c (bpfinishpy_init): Adjust to use
inferior_thread.
* python/py-inferior.c (struct inferior_object): Give the type a
tag name instead of a typedef.
(python_on_normal_stop): No need to check if the current thread is
listed.
(inferior_to_inferior_object): Change return type to
inferior_object. All callers adjusted.
(find_thread_object): Delete, bits factored out to ...
(thread_to_thread_object): ... this new function.
* python/py-infthread.c (create_thread_object): Use
inferior_to_inferior_object.
(thpy_is_stopped): Use thread pointer directly.
(gdbpy_selected_thread): Use inferior_thread.
* python/py-record-btrace.c (btpy_list_object) <ptid>: Delete
field, replaced with ...
<thread>: ... this new field. All users adjusted.
(btpy_insn_or_gap_new): Drop const.
(btpy_list_new): Take a thread pointer instead of a ptid_t. All
callers adjusted.
* python/py-record.c: Include "gdbthread.h".
(recpy_insn_new, recpy_func_new): Take a thread pointer instead of
a ptid_t. All callers adjusted.
(gdbpy_current_recording): Use inferior_thread.
* python/py-record.h (recpy_record_object) <ptid>: Delete
field, replaced with ...
<thread>: ... this new field. All users adjusted.
(recpy_element_object) <ptid>: Delete
field, replaced with ...
<thread>: ... this new field. All users adjusted.
(recpy_insn_new, recpy_func_new): Take a thread pointer instead of
a ptid_t. All callers adjusted.
* python/py-threadevent.c: Include "gdbthread.h".
(get_event_thread): Use thread_to_thread_object.
* python/python-internal.h (struct inferior_object): Forward
declare.
(find_thread_object, find_inferior_object): Delete declarations.
(thread_to_thread_object, inferior_to_inferior_object): New
declarations.
* record-btrace.c: Include "inferior.h".
(require_btrace_thread): Use inferior_thread.
(record_btrace_frame_sniffer)
(record_btrace_tailcall_frame_sniffer): Use inferior_thread.
(get_thread_current_frame): Use scoped_restore_current_thread and
switch_to_thread.
(get_thread_current_frame): Use thread pointer directly.
(record_btrace_replay_at_breakpoint): Use thread's inferior
pointer directly.
* record-full.c: Include "inferior.h".
* regcache.c: Include "gdbthread.h".
(get_thread_arch_regcache): Use the inferior's address space
directly.
(get_thread_regcache, registers_changed_thread): New.
* regcache.h (get_thread_regcache(thread_info *thread)): New
overload.
(registers_changed_thread): New.
(remote_target) <remote_detach_1>: Swap order of parameters.
(remote_add_thread): <remote_add_thread>: Return the new thread.
(get_remote_thread_info(ptid_t)): New overload.
(remote_target::remote_notice_new_inferior): Use thread pointers
directly.
(remote_target::process_initial_stop_replies): Use
thread_info::set_running.
(remote_target::remote_detach_1, remote_target::detach)
(extended_remote_target::detach): Adjust.
* stack.c (frame_show_address): Use inferior_thread.
* target-debug.h (target_debug_print_thread_info_pp): New.
* target-delegates.c: Regenerate.
* target.c (default_thread_address_space): Delete.
(memory_xfer_partial_1): Use current_inferior.
(target_detach): Use current_inferior.
(target_thread_address_space): Delete.
(generic_mourn_inferior): Use current_inferior.
* target.h (struct target_ops) <thread_address_space>: Delete.
(target_thread_address_space): Delete.
* thread.c (init_thread_list): Use ALL_THREADS_SAFE. Use thread
pointers directly.
(delete_thread_1, delete_thread, delete_thread_silent): Take a
thread pointer instead of a ptid_t. Adjust all callers.
(ptid_to_global_thread_id, global_thread_id_to_ptid): Delete.
(first_thread_of_process): Delete, replaced by ...
(first_thread_of_inferior): ... this new function. All callers
adjusted.
(any_thread_of_process): Rename to ...
(any_thread_of_inferior): ... this, and take an inferior pointer.
(any_live_thread_of_process): Rename to ...
(any_live_thread_of_inferior): ... this, and take an inferior
pointer.
(thread_stack_temporaries_enabled_p, push_thread_stack_temporary)
(value_in_thread_stack_temporaries)
(get_last_thread_stack_temporary): Take a thread pointer instead
of a ptid_t. Adjust all callers.
(thread_info::set_running): New.
(validate_registers_access): Use inferior_thread.
(can_access_registers_ptid): Rename to ...
(can_access_registers_thread): ... this, and take a thread
pointer.
(print_thread_info_1): Adjust to compare thread pointers instead
of ptids.
(switch_to_no_thread, switch_to_thread): Make extern.
(scoped_restore_current_thread::~scoped_restore_current_thread):
Use m_thread pointer directly.
(scoped_restore_current_thread::scoped_restore_current_thread):
Use inferior_thread.
(thread_command): Use thread pointer directly.
(thread_num_make_value_helper): Use inferior_thread.
* top.c (execute_command): Use inferior_thread.
* tui/tui-interp.c: Include "inferior.h".
* varobj.c (varobj_create): Use inferior_thread.
(value_of_root_1): Use find_thread_global_id instead of
global_thread_id_to_ptid.
When compiling with clang 6, I see a bunch of warnings like this:
/home/emaisin/src/binutils-gdb/gdb/amd64-linux-tdep.c:1427:8: error: comparison of two values with different enumeration types in switch statement ('enum amd64_syscall' and 'amd
64_x32_syscall') [-Werror,-Wenum-compare-switch]
case amd64_x32_sys_move_pages:
^~~~~~~~~~~~~~~~~~~~~~~~
In this switch, we indeed use enumerators of both types
amd64_x32_syscall and amd64_syscall. This is done on purpose, and the
enum values are chosen so that they are complementary.
I think it's still a useful warning, so I chose to ignore just that
particular case.
gdb/ChangeLog:
* common/diagnostics.h
(DIAGNOSTIC_IGNORE_SWITCH_DIFFERENT_ENUM_TYPES): New macro.
* amd64-linux-tdep.c (amd64_canonicalize_syscall): Use it.
Andrew Burgess