596 Commits

Author SHA1 Message Date
5aca7eaa2b [gdb/tdep] Add amd64/i386 epilogue override unwinders
For amd64 the current frame-unwinders are:
...
$ gdb -q -batch -ex "set arch i386:x86-64" -ex "maint info frame-unwinders"
The target architecture is set to "i386:x86-64".
dummy                   DUMMY_FRAME
dwarf2 tailcall         TAILCALL_FRAME
inline                  INLINE_FRAME
python                  NORMAL_FRAME
amd64 epilogue          NORMAL_FRAME
dwarf2                  NORMAL_FRAME
dwarf2 signal           SIGTRAMP_FRAME
amd64 sigtramp          SIGTRAMP_FRAME
amd64 prologue          NORMAL_FRAME
...

For a -g0 -fasynchronous-unwind-tables exec (without .debug_info but with
.eh_frame section), we'd like to start using the dwarf2 unwinder instead of
the "amd64 epilogue" unwinder, by returning true in
compunit_epilogue_unwind_valid for cust == nullptr.

But we'd run into the following problem for a -g0
-fno-asynchronous-unwind-tables (without .debug_info and .eh_frame section)
exec:
- the "amd64 epilogue" unwinder would not run
  (because compunit_epilogue_unwind_valid () == true)
- the dwarf2 unwinder would also not run
  (because there's no .eh_frame info).

Fix this by:
- renaming the "amd64 epilogue" unwinder to "amd64 epilogue override", and
- adding a fallback "amd64 epilogue" after the dwarf unwinders,
while making sure that only one of the two is active.  Likewise for i386.  NFC.

For amd64, this results in this change:
...
 $ gdb -q -batch -ex "set arch i386:x86-64" -ex "maint info frame-unwinders"
 The target architecture is set to "i386:x86-64".
 dummy                   DUMMY_FRAME
 dwarf2 tailcall         TAILCALL_FRAME
 inline                  INLINE_FRAME
 python                  NORMAL_FRAME
-amd64 epilogue          NORMAL_FRAME
+amd64 epilogue override NORMAL_FRAME
 dwarf2                  NORMAL_FRAME
 dwarf2 signal           SIGTRAMP_FRAME
+amd64 epilogue          NORMAL_FRAME
 amd64 sigtramp          SIGTRAMP_FRAME
 amd64 prologue          NORMAL_FRAME
...

And for i386:
...
 $ gdb -q -batch -ex "set arch i386" -ex "maint info frame-unwinders"
 The target architecture is set to "i386".
 dummy                   DUMMY_FRAME
 dwarf2 tailcall         TAILCALL_FRAME
 iline                  INLINE_FRAME
-i386 epilogue           NORMAL_FRAME
+i386 epilogue override  NORMAL_FRAME
 dwarf2                  NORMAL_FRAME
 dwarf2 signal           SIGTRAMP_FRAME
+i386 epilogue           NORMAL_FRAME
 i386 stack tramp        NORMAL_FRAME
 i386 sigtramp           SIGTRAMP_FRAME
 i386 prologue           NORMAL_FRAME
...
2023-02-20 12:20:14 +01:00
2f9f989c2b [gdb/tdep] Fix amd64/i386_stack_frame_destroyed_p
The use of compunit_epilogue_unwind_valid in both amd64_stack_frame_destroyed_p
and i386_stack_frame_destroyed_p is problematic, in the sense that the
functions no longer match their documented behaviour.

Fix this by moving the use of compunit_epilogue_unwind_valid to
amd64_epilogue_frame_sniffer and i386_epilogue_frame_sniffer.  No functional
changes.
2023-02-20 12:20:14 +01:00
cb911672fb [gdb/symtab] Factor out compunit_epilogue_unwind_valid
Factor out compunit_epilogue_unwind_valid from both
amd64_stack_frame_destroyed_p and i386_stack_frame_destroyed_p.  No functional
changes.

Also add a comment in the new function about the assumption that in absence of
producer information, epilogue unwind info is invalid.

Approved-By: Tom Tromey <tom@tromey.com>
2023-02-20 12:20:14 +01:00
ecbc5c4f90 gdb, fortran: Fix quad floating-point type for ifort compiler.
I fixed this a while ago for ifx, one of the two Intel compilers, in
8d624a9d8050ca96e154215c7858ac5c2d8b0b19.

Apparently I missed that the older ifort Intel compiler actually emits
slightly different debug info again:

0x0000007a:   DW_TAG_base_type
                DW_AT_byte_size	(0x20)
                DW_AT_encoding	(DW_ATE_complex_float)
                DW_AT_name	("COMPLEX(16)")

0x00000081:   DW_TAG_base_type
                DW_AT_byte_size	(0x10)
                DW_AT_encoding	(DW_ATE_float)
                DW_AT_name	("REAL(16)")

This fixes two failures in gdb.fortran/complex.exp with ifort.

Approved-By: Tom Tromey <tom@tromey.com>
2023-02-15 09:51:28 +01:00
6f9c9d71c2 Introduce set_lval method on value
This introduces the set_lval method on value, one step toward removing
deprecated_lval_hack.  Ultimately I think the goal should be for some
of these set_* methods to be replaced with constructors; but I haven't
done this, as the series is already too long.  Other 'deprecated'
methods can probably be handled the same way.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-02-13 15:22:20 -07:00
d00664dbba Turn many optimized-out value functions into methods
This turns many functions that are related to optimized-out or
availability-checking to be methods of value.  The static function
value_entirely_covered_by_range_vector is also converted to be a
private method.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-02-13 15:22:17 -07:00
efaf1ae025 Turn remaining value_contents functions into methods
This turns the remaining value_contents functions -- value_contents,
value_contents_all, value_contents_for_printing, and
value_contents_for_printing_const -- into methods of value.  It also
converts the static functions require_not_optimized_out and
require_available to be private methods.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-02-13 15:22:16 -07:00
bbe912ba88 Turn some value_contents functions into methods
This turns value_contents_raw, value_contents_writeable, and
value_contents_all_raw into methods on value.  The remaining functions
will be changed later in the series; they were a bit trickier and so I
didn't include them in this patch.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-02-13 15:21:08 -07:00
317c3ed9fc Turn allocate_value into a static "constructor"
This changes allocate_value to be a static "constructor" of value.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-02-13 15:21:07 -07:00
463b870d01 Turn value_enclosing_type into method
This changes value_enclosing_type to be a method of value.  Much of
this patch was written by script.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-02-13 15:21:07 -07:00
81ae560ca4 Turn deprecated_set_value_type into a method
This changes deprecated_set_value_type to be a method of value.  Much
of this patch was written by script.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-02-13 15:21:07 -07:00
d0c9791728 Turn value_type into method
This changes value_type to be a method of value.  Much of this patch
was written by script.

Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-02-13 15:21:06 -07:00
af0d0f34d8 [gdb/tdep] Don't use i386 unwinder for amd64
For i386 we have these unwinders:
...
$ gdb -q -batch -ex "set arch i386" -ex "maint info frame-unwinders"
The target architecture is set to "i386".
dummy                   DUMMY_FRAME
dwarf2 tailcall         TAILCALL_FRAME
inline                  INLINE_FRAME
i386 epilogue           NORMAL_FRAME
dwarf2                  NORMAL_FRAME
dwarf2 signal           SIGTRAMP_FRAME
i386 stack tramp        NORMAL_FRAME
i386 sigtramp           SIGTRAMP_FRAME
i386 prologue           NORMAL_FRAME
...
and for amd64:
...
$ gdb -q -batch -ex "set arch i386:x86-64" -ex "maint info frame-unwinders"
The target architecture is set to "i386:x86-64".
dummy                   DUMMY_FRAME
dwarf2 tailcall         TAILCALL_FRAME
inline                  INLINE_FRAME
python                  NORMAL_FRAME
amd64 epilogue          NORMAL_FRAME
i386 epilogue           NORMAL_FRAME
dwarf2                  NORMAL_FRAME
dwarf2 signal           SIGTRAMP_FRAME
amd64 sigtramp          SIGTRAMP_FRAME
amd64 prologue          NORMAL_FRAME
i386 stack tramp        NORMAL_FRAME
i386 sigtramp           SIGTRAMP_FRAME
i386 prologue           NORMAL_FRAME
...

ISTM me there's no reason for the i386 unwinders to be there for amd64.

Furthermore, there's a generic need to play around with enabling and disabling
unwinders, see PR8434.  Currently, that's only available for both the dwarf2
unwinders at once using "maint set dwarf unwinders on/off".

If I manually disable the "amd64 epilogue" unwinder, the "i386 epilogue"
unwinder becomes active and gives the wrong answer, while I'm actually
interested in the result of the dwarf2 unwinder.  Of course I can also
manually disable the "i386 epilogue", but I take the fact that I have to do
that as evidence that on amd64, the "i386 epilogue" is not only unnecessary,
but in the way.

Fix this by only adding the i386 unwinders if
"info.bfd_arch_info->bits_per_word == 32".

Note that the x32 abi (x86_64/-mx32):
- has the same unwinder list as amd64 (x86_64/-m64) before this commit,
- has info.bfd_arch_info->bits_per_word == 64, the same as amd64, and
  consequently,
- has the same unwinder list as amd64 after this commit.

Tested on x86_64-linux, -m64 and -m32.  Not tested with -mx32.

Reviewed-By: John Baldwin <jhb@freebsd.org>

PR tdep/30102
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30102
2023-02-11 09:04:51 +01:00
2b16913cdc gdb: make gdbarch_alloc take ownership of the tdep
It's currently not clear how the ownership of gdbarch_tdep objects
works.  In fact, nothing ever takes ownership of it.  This is mostly
fine because we never free gdbarch objects, and thus we never free
gdbarch_tdep objects.  There is an exception to that however: when
initialization fails, we do free the gdbarch object that is not going to
be used, and we free the tdep too.  Currently, i386 and s390 do it.

To make things clearer, change gdbarch_alloc so that it takes ownership
of the tdep.  The tdep is thus automatically freed if the gdbarch is
freed.

Change all gdbarch initialization functions to pass a new gdbarch_tdep
object to gdbarch_alloc and then retrieve a non-owning reference from
the gdbarch object.

Before this patch, the xtensa architecture had a single global instance
of xtensa_gdbarch_tdep.  Since we need to pass a dynamically allocated
gdbarch_tdep_base instance to gdbarch_alloc, remove this global
instance, and dynamically allocate one as needed, like we do for all
other architectures.  Make the `rmap` array externally visible and
rename it to the less collision-prone `xtensa_rmap` name.

Change-Id: Id3d70493ef80ce4bdff701c57636f4c79ed8aea2
Approved-By: Andrew Burgess <aburgess@redhat.com>
2023-01-05 14:38:51 -05:00
911627e7b1 Fix inferior calls with variably-sized return type
This patch updates the gdbarch_return_value_as_value implementations
to work correctly with variably-sized return types.
2023-01-03 08:45:01 -07:00
5cb0f2d5b6 Convert selected architectures to gdbarch_return_value_as_value
This converts a few selected architectures to use
gdbarch_return_value_as_value rather than gdbarch_return_value.  The
architectures are just the ones that I am able to test.  This patch
should not introduce any behavior changes.
2023-01-03 08:45:01 -07:00
213516ef31 Update copyright year range in header of all files managed by GDB
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.
2023-01-01 17:01:16 +04:00
f34652de0b internal_error: remove need to pass __FILE__/__LINE__
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
2022-10-19 15:32:36 +01:00
bd2b40ac12 Change GDB to use frame_info_ptr
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>
2022-10-10 11:57:10 +02:00
df86565b31 gdb: remove TYPE_LENGTH
Remove the macro, replace all uses with calls to type::length.

Change-Id: Ib9bdc954576860b21190886534c99103d6a47afb
2022-09-21 11:05:21 -04:00
27710edb4e gdb: remove TYPE_TARGET_TYPE
Remove the macro, replace all uses by calls to type::target_type.

Change-Id: Ie51d3e1e22f94130176d6abd723255282bb6d1ed
2022-09-21 10:59:49 -04:00
ec29a63c80 Remove register_gdbarch_init
This removes the deprecated register_gdbarch_init in favor a default
argument to gdbarch_register.  Regression tested on x86-64 Fedora 34.
2022-08-16 07:29:46 -06:00
98badbfdc2 Use gdb_bfd_ref_ptr in objfile
This changes struct objfile to use a gdb_bfd_ref_ptr.  In addition to
removing some manual memory management, this fixes a use-after-free
that was introduced by the registry rewrite series.  The issue there
was that, in some cases, registry shutdown could refer to memory that
had already been freed.  This help fix the bug by delaying the
destruction of the BFD reference (and thus the per-bfd object) until
after the registry has been shut down.
2022-08-03 13:26:58 -06:00
08106042d9 gdb: move the type cast into gdbarch_tdep
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.
2022-07-21 15:19:42 +01:00
e7fe101149 gdb: more 'const' in gdb/reggroups.{c,h}
Convert the reggroup_new and reggroup_gdbarch_new functions to return
a 'const regggroup *', and fix up all the fallout.

There should be no user visible changes after this commit.
2022-04-07 16:01:18 +01:00
e7d69e72bf gdb: always add the default register groups
There's a set of 7 default register groups.  If we don't add any
gdbarch specific register groups during gdbarch initialisation, then
when we iterate over the register groups using reggroup_next and
reggroup_prev we will make use of these 7 default groups.  See the use
of default_groups in gdb/reggroups.c for details on this.

However, if the gdbarch adds its own groups during gdbarch
initialisation, then these groups will be used in preference to the
default groups.

A problem arises though if the particular architecture makes use of
the target description mechanism.  If the default target
description(s) (i.e. those internal to GDB that are used when the user
doesn't provide their own) don't mention any additional register
groups then the default register groups will be used.

But if the target description does mention additional groups then the
default groups are not used, and instead, the groups from the target
description are used.

The problem with this is that what usually happens is that the target
description will mention additional groups, e.g. groups for special
registers.  Most architectures that use target descriptions work
around this by adding all (or most) of the default register groups in
all cases.  See i386_add_reggroups, aarch64_add_reggroups,
riscv_add_reggroups, xtensa_add_reggroups, and others.

In this patch, my suggestion is that we should just add the default
register groups for every architecture, always.  This change is in
gdb/reggroups.c.

All the remaining changes are me updating the various architectures to
not add the default groups themselves.

So, where will this change be visible to the user?  I think the
following commands will possibly change:

* info registers / info all-registers:

  The user can provide a register group to these commands.  For example,
  on csky, we previously never added the 'vector' group.  Now, as a
  default group, this will be available, but (presumably) will not
  contain any registers.  I don't think this is necessarily a bad
  thing, there's something to be said for having some consistent
  defaults available.  There are other architectures that didn't add
  all 7 of the defaults, which will now have gained additional groups.

* maint print reggroups

  This prints the set of all available groups.  As a maintenance
  command I'm less concerned with the output changing here.
  Obviously, for the architectures that didn't previously add all the
  defaults, this list just got bigger.

* maint print register-groups

  This prints all the registers, and the groups they are in.  If the
  defaults were not previously being added then a register (obviously)
  can't appear in one of the default groups.  Now the groups are
  available then registers might be in more groups than previously.
  However, this is again a maintenance command, so I'm less concerned
  about this changing.
2022-04-07 16:01:18 +01:00
dbf5d61bda gdb: make gdbarch_register_reggroup_p take a const reggroup *
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.
2022-04-07 16:01:17 +01:00
552f1157c6 gdb: rename floatformats_ia64_quad to floatformats_ieee_quad
It is better to rename floatformats_ia64_quad to floatformats_ieee_quad
to reflect the reality, and then we can clean up the related code.

As Tom Tromey said [1]:

  These files are maintained in gcc and then imported into the
  binutils-gdb repository, so any changes to them will have to
  be proposed there first.

the related changes have been merged into gcc master now [2], it is time
to do it for gdb.

[1] https://sourceware.org/pipermail/gdb-patches/2022-March/186569.html
[2] https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=b2dff6b2d9d6

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
2022-04-02 08:36:33 +08:00
6cb06a8cda Unify gdb printf functions
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.
2022-03-29 12:46:24 -06:00
3908b699f8 gdb: remove COMPUNIT_EPILOGUE_UNWIND_VALID macro, add getter/setter
Add a getter and a setter for a compunit_symtab's epilogue unwind valid flag.
Remove the corresponding macro and adjust all callers.

Change-Id: If3b68629d987767da9be7041a95d96dc34367a9a
2022-02-06 15:48:19 -05:00
ab5f850eed gdb: remove COMPUNIT_PRODUCER macro, add getter/setter
Add a getter and a setter for a compunit_symtab's producer.  Remove the
corresponding macro and adjust all callers.

Change-Id: Ia1d6d8a0e247a08a21af23819d71e49b37d8931b
2022-02-06 15:48:18 -05:00
56c5b29b61 Use filtered output in *-tdep commands
Various targets introduce their own commands, which then use
unfiltered output.  It's better to use filtered output by default, so
this patch fixes the instances I found.
2022-01-05 11:36:33 -07:00
4a94e36819 Automatic Copyright Year update after running gdb/copyright.py
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.
2022-01-01 19:13:23 +04:00
d68510ac19 Use correct stream for process record output
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
2021-12-29 10:40:10 -07:00
545e49f5ee [gdb/tdep] Fix inferior plt calls in PIE for i386
Consider test-case test.c:
...
int main (void) {
  void *p = malloc (10);
  return 0;
}
...

When compiled to a non-PIE exec:
...
$ gcc -m32 test.c
...
the call sequence looks like:
...
 8048447:       83 ec 0c                sub    $0xc,%esp
 804844a:       6a 0a                   push   $0xa
 804844c:       e8 bf fe ff ff          call   8048310 <malloc@plt>
...
which calls to:
...
08048310 <malloc@plt>:
 8048310:       ff 25 0c a0 04 08       jmp    *0x804a00c
 8048316:       68 00 00 00 00          push   $0x0
 804831b:       e9 e0 ff ff ff          jmp    8048300 <.plt>
...
where the first insn at 0x8048310 initially jumps to the following address
0x8048316, read from the .got.plt @ 0x804a00c:
...
 804a000 0c9f0408 00000000 00000000 16830408  ................
 804a010 26830408                             &...
...

Likewise, when compiled as a PIE:
...
$ gcc -m32 -fPIE -pie test.c
...
we have this call sequence (with %ebx setup to point to the .got.plt):
...
0000055d <main>:
 579:   83 ec 0c                sub    $0xc,%esp
 57c:   6a 0a                   push   $0xa
 57e:   89 c3                   mov    %eax,%ebx
 580:   e8 6b fe ff ff          call   3f0 <malloc@plt>
...
which calls to:
...
000003f0 <malloc@plt>:
 3f0:   ff a3 0c 00 00 00       jmp    *0xc(%ebx)
 3f6:   68 00 00 00 00          push   $0x0
 3fb:   e9 e0 ff ff ff          jmp    3e0 <.plt>
...
where the insn at 0x3f0 initially jumps to following address 0x3f6, read from
the .got.plt at offset 0xc:
...
 2000 f41e0000 00000000 00000000 f6030000  ................
 2010 06040000                             ....
...

When instead doing an inferior call to malloc (with nosharedlib to force
malloc to resolve to malloc@plt rather than the functions in ld.so or libc.so)
with the non-PIE exec, we have the expected:
...
$ gdb -q -batch a.out -ex start -ex nosharedlib -ex "p /x (void *)malloc (10)"
Temporary breakpoint 1 at 0x8048444

Temporary breakpoint 1, 0x08048444 in main ()
$1 = 0x804b160
...

But with the PIE exec, we run into:
...
$ gdb -q -batch a.out -ex start -ex nosharedlib -ex "p /x (void *)malloc (10)"
Temporary breakpoint 1 at 0x56c

Temporary breakpoint 1, 0x5655556c in main ()

Program received signal SIGSEGV, Segmentation fault.
0x565553f0 in malloc@plt ()
...

The segfault happens because:
- the inferior call mechanism doesn't setup %ebx
- %ebx instead is 0
- the jump to "*0xc(%ebx)" reads from memory at 0xc

Fix this by setting up %ebx properly in i386_thiscall_push_dummy_call.

Fixes this failure with target board unix/-m32/-pie/-fPIE reported in
PR28467:
...
FAIL: gdb.base/nodebug.exp: p/c (int) array_index("abcdef",2)
...

Tested on x86_64-linux, with target board unix/-m32 and unix/-m32/-fPIE/-pie.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28467
2021-12-07 08:07:18 +01:00
345bd07cce gdb: fix gdbarch_tdep ODR violation
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
2021-11-15 11:29:39 -05:00
f54bdb6d27 gdb: add add_setshow_prefix_cmd
There's a common pattern to call add_basic_prefix_cmd and
add_show_prefix_cmd to add matching set and show commands.  Add the
add_setshow_prefix_cmd function to factor that out and use it at a few
places.

Change-Id: I6e9e90a30e9efb7b255bf839cac27b85d7069cfd
2021-10-28 10:44:18 -04:00
50888e42dc gdb: change functions returning value contents to use gdb::array_view
The bug fixed by this [1] patch was caused by an out-of-bounds access to
a value's content.  The code gets the value's content (just a pointer)
and then indexes it with a non-sensical index.

This made me think of changing functions that return value contents to
return array_views instead of a plain pointer.  This has the advantage
that when GDB is built with _GLIBCXX_DEBUG, accesses to the array_view
are checked, making bugs more apparent / easier to find.

This patch changes the return types of these functions, and updates
callers to call .data() on the result, meaning it's not changing
anything in practice.  Additional work will be needed (which can be done
little by little) to make callers propagate the use of array_view and
reap the benefits.

[1] https://sourceware.org/pipermail/gdb-patches/2021-September/182306.html

Change-Id: I5151f888f169e1c36abe2cbc57620110673816f3
2021-10-25 14:51:44 -04:00
0b99a66053 gdb: Enable finish command and inferior calls for _Float16 on amd64 and i386.
Values of type _Float16 and _Float16 _Complex can now be used on CPUs with
AVX512-FP16 support. Return values of those types are located in XMM0.
Compiler support for gcc and clang is in progress, see e.g.:
https://gcc.gnu.org/pipermail/gcc-patches/2021-July/574117.html

gdb/ChangeLog:
2021-07-21  Felix Willgerodt  <Felix.Willgerodt@intel.com>

	* amd64-tdep.c (amd64_classify): Classify _Float16 and
	_Float16 _Complex as AMD64_SSE.
	* i386-tdep.c (i386_extract_return_value): Read _Float16 and
	_Float16 _Complex from xmm0.

gdb/testsuite/ChangeLog:
2021-07-21  Felix Willgerodt  <Felix.Willgerodt@intel.com>

	* gdb.arch/x86-avx512fp16-abi.c: New file.
	* gdb.arch/x86-avx512fp16-abi.exp: New file.
2021-09-03 15:18:31 +02:00
8661f70c49 Add half support for AVX512 register view.
This adds support for the half datatype, FP16, to the AVX512 register printing.

gdb/ChangeLog:
2020-07-21  Felix Willgerodt  <Felix.Willgerodt@intel.com>

	* i386-tdep.c (i386_zmm_type) <v32_half>: New field.
	(i386_ymm_type) <v16_half>: New field.
	(i386_gdbarch_init): Add set_gdbarch_half_format.
	* features/i386/64bit-avx512.xml: Add half type.
	* features/i386/64bit-avx512.c: Regenerated.
	* features/i386/64bit-sse.xml: Add half type.
	* features/i386/64bit-sse.c: Regenerated.

gdb/testsuite/ChangeLog:
2021-07-21  Felix Willgerodt  <Felix.Willgerodt@intel.com>

	* gdb.arch/x86-avx512fp16.c: New file.
	* gdb.arch/x86-avx512fp16.exp: New file.
	* lib/gdb.exp (skip_avx512fp16_tests): New function.
2021-09-03 15:18:31 +02:00
a154d838a7 gdb: add names to unwinders, add debug messages when looking for unwinder
I wrote this while debugging a problem where the expected unwinder for a
frame wasn't used.  It adds messages to show which unwinders are
considered for a frame, why they are not selected (if an exception is
thrown), and finally which unwinder is selected in the end.

To be able to show a meaningful, human-readable name for the unwinders,
add a "name" field to struct frame_unwind, and update all instances to
include a name.

Here's an example of the output:

    [frame] frame_unwind_find_by_frame: this_frame=0
    [frame] frame_unwind_try_unwinder: trying unwinder "dummy"
    [frame] frame_unwind_try_unwinder: no
    [frame] frame_unwind_try_unwinder: trying unwinder "dwarf2 tailcall"
    [frame] frame_unwind_try_unwinder: no
    [frame] frame_unwind_try_unwinder: trying unwinder "inline"
    [frame] frame_unwind_try_unwinder: no
    [frame] frame_unwind_try_unwinder: trying unwinder "jit"
    [frame] frame_unwind_try_unwinder: no
    [frame] frame_unwind_try_unwinder: trying unwinder "python"
    [frame] frame_unwind_try_unwinder: no
    [frame] frame_unwind_try_unwinder: trying unwinder "amd64 epilogue"
    [frame] frame_unwind_try_unwinder: no
    [frame] frame_unwind_try_unwinder: trying unwinder "i386 epilogue"
    [frame] frame_unwind_try_unwinder: no
    [frame] frame_unwind_try_unwinder: trying unwinder "dwarf2"
    [frame] frame_unwind_try_unwinder: yes

gdb/ChangeLog:

	* frame-unwind.h (struct frame_unwind) <name>: New.  Update
	instances everywhere to include this field.
	* frame-unwind.c (frame_unwind_try_unwinder,
	frame_unwind_find_by_frame): Add debug messages.

Change-Id: I813f17777422425f0d08b22499817b23922e8ddb
2021-06-29 12:05:03 -04:00
24b21115f5 gdb: fix tab after space indentation issues
I spotted some indentation issues where we had some spaces followed by
tabs at beginning of line, that I wanted to fix.  So while at it, I did
a quick grep to find and fix all I could find.

gdb/ChangeLog:

	* Fix tab after space indentation issues throughout.

Change-Id: I1acb414dd9c593b474ae2b8667496584df4316fd
2021-05-27 15:18:49 -04:00
01add95bed gdb: fix some indentation issues
I wrote a small script to spot a pattern of indentation mistakes I saw
happened in breakpoint.c.  And while at it I ran it on all files and
fixed what I found.  No behavior changes intended, just indentation and
addition / removal of curly braces.

gdb/ChangeLog:

	* Fix some indentation mistakes throughout.

gdbserver/ChangeLog:

	* Fix some indentation mistakes throughout.

Change-Id: Ia01990c26c38e83a243d8f33da1d494f16315c6e
2021-05-27 15:01:28 -04:00
2f822da535 gdb: generate the prefix name for prefix commands on demand
Previously, the prefixname field of struct cmd_list_element was manually
set for prefix commands.  This seems verbose and error prone as it
required every single call to functions adding prefix commands to
specify the prefix name while the same information can be easily
generated.

Historically, this was not possible as the prefix field was null for
many commands, but this was fixed in commit
3f4d92ebdf7f848b5ccc9e8d8e8514c64fde1183 by Philippe Waroquiers, so
we can rely on the prefix field being set when generating the prefix
name.

This commit also fixes a use after free in this scenario:
* A command gets created via Python (using the gdb.Command class).
  The prefix name member is dynamically allocated.
* An alias to the new command is created. The alias's prefixname is set
  to point to the prefixname for the original command with a direct
  assignment.
* A new command with the same name as the Python command is created.
* The object for the original Python command gets freed and its
  prefixname gets freed as well.
* The alias is updated to point to the new command, but its prefixname
  is not updated so it keeps pointing to the freed one.

gdb/ChangeLog:

	* command.h (add_prefix_cmd): Remove the prefixname argument as
	it can now be generated automatically.  Update all callers.
	(add_basic_prefix_cmd): Ditto.
	(add_show_prefix_cmd): Ditto.
	(add_prefix_cmd_suppress_notification): Ditto.
	(add_abbrev_prefix_cmd): Ditto.
	* cli/cli-decode.c (add_prefix_cmd): Ditto.
	(add_basic_prefix_cmd): Ditto.
	(add_show_prefix_cmd): Ditto.
	(add_prefix_cmd_suppress_notification): Ditto.
	(add_prefix_cmd_suppress_notification): Ditto.
	(add_abbrev_prefix_cmd): Ditto.
	* cli/cli-decode.h (struct cmd_list_element): Replace the
	prefixname member variable with a method which generates the
	prefix name at runtime.  Update all code reading the prefix
	name to use the method, and remove all code setting it.
	* python/py-cmd.c (cmdpy_destroyer): Remove code to free the
	prefixname member as it's now a method.
	(cmdpy_function): Determine if the command is a prefix by
	looking at prefixlist, not prefixname.
2021-05-12 11:19:22 +01:00
16e311ab6d gdb: Allow prologue detection via symbols for Intel compilers.
The next-gen Intel Fortran compiler isn't flang-based, but emits
prologue_end in the same manner.  As do the newer Intel C/C++ compilers.
This allows prologue detection based on dwarf for all newer Intel compilers.
The cut-off version was not chosen for any specific reason other than the
effort to test this.

gdb/Changelog:
2021-04-08  Felix Willgerodt  <felix.willgerodt@intel.com>

    	* i386-tdep.c (i386_skip_prologue): Use symbol table to find the
    	prologue end for Intel compilers.
    	* amd64-tdep.c (amd64_skip_prologue): Likewise.
    	* producer.c (producer_is_icc_ge_19): New function.
    	* producer.h (producer_is_icc_ge_19): New declaration.
2021-04-08 09:19:57 +02:00
8d624a9d80 gdb/fortran: Fix quad floating-point type for Intel compilers.
Intel Fortran compilers emit the following DWARF for gdb.fortran/complex.f90:

0x00000071:   DW_TAG_base_type
                DW_AT_name	("COMPLEX*32")
                DW_AT_encoding	(DW_ATE_complex_float)
                DW_AT_byte_size	(0x20)

0x00000078:   DW_TAG_base_type
                DW_AT_name	("REAL*16")
                DW_AT_encoding	(DW_ATE_float)
                DW_AT_byte_size	(0x10)

This results in GDB not reading the right values, as it wrongly assumes the
default floatformat "floatformat_i387_ext" instead of
"floatformat_ia64_quad_little".

gdb/ChangeLog:
2021-03-15  Felix Willgerodt  <felix.willgerodt@intel.com>

	* i386-tdep.c (i386_floatformat_for_type): Add COMPLEX*32 and REAL*16.
2021-03-15 11:02:31 +01:00
4c5e7a930a Convert stap probes to create operations
This changes the stap probe code to create operations, rather than
exp_elements.

gdb/ChangeLog
2021-03-08  Tom Tromey  <tom@tromey.com>

	* stap-probe.c (binop_maker_ftype): New typedef.
	(stap_maker_map): New global.
	(stap_make_binop): New function.
	(stap_parse_register_operand): Return operation_up.
	(stap_parse_single_operand, stap_parse_argument_conditionally)
	(stap_parse_argument_1): Likewise.
	(stap_parse_argument): Create operations.
	(stap_probe::parse_arguments): Update.
	(_initialize_stap_probe): Initialize stap_maker_map.
	* ppc-linux-tdep.c (ppc_stap_parse_special_token): Change return
	type.
	* i386-tdep.h (i386_stap_parse_special_token): Change return
	type.
	* i386-tdep.c (i386_stap_parse_special_token_triplet)
	(i386_stap_parse_special_token_three_arg_disp)
	(i386_stap_parse_special_token): Change return type.
	* gdbarch.sh (stap_parse_special_token): Change return type.
	* gdbarch.c: Rebuild.
	* gdbarch.h: Rebuild.
	* arm-linux-tdep.c (arm_stap_parse_special_token): Change return
	type.
	* aarch64-linux-tdep.c (aarch64_stap_parse_special_token): Change
	return type.
2021-03-08 07:28:38 -07:00
6bd434d6ca gdb: make some variables static
I'm trying to enable clang's -Wmissing-variable-declarations warning.
This patch fixes all the obvious spots where we can simply add "static"
(at least, found when building on x86-64 Linux).

gdb/ChangeLog:

	* aarch64-linux-tdep.c (aarch64_linux_record_tdep): Make static.
	* aarch64-tdep.c (tdesc_aarch64_list, aarch64_prologue_unwind,
	aarch64_stub_unwind, aarch64_normal_base, ): Make static.
	* arm-linux-tdep.c (arm_prologue_unwind): Make static.
	* arm-tdep.c (struct frame_unwind): Make static.
	* auto-load.c (auto_load_safe_path_vec): Make static.
	* csky-tdep.c (csky_stub_unwind): Make static.
	* gdbarch.c (gdbarch_data_registry): Make static.
	* gnu-v2-abi.c (gnu_v2_abi_ops): Make static.
	* i386-netbsd-tdep.c (i386nbsd_mc_reg_offset): Make static.
	* i386-tdep.c (i386_frame_setup_skip_insns,
	i386_tramp_chain_in_reg_insns, i386_tramp_chain_on_stack_insns):
	Make static.
	* infrun.c (observer_mode): Make static.
	* linux-nat.c (sigchld_action): Make static.
	* linux-thread-db.c (thread_db_list): Make static.
	* maint-test-options.c (maintenance_test_options_list):
	* mep-tdep.c (mep_csr_registers): Make static.
	* mi/mi-cmds.c (struct mi_cmd_stats): Remove struct type name.
	(stats): Make static.
	* nat/linux-osdata.c (struct osdata_type): Make static.
	* ppc-netbsd-tdep.c (ppcnbsd_reg_offsets): Make static.
	* progspace.c (last_program_space_num): Make static.
	* python/py-param.c (struct parm_constant): Remove struct type
	name.
	(parm_constants): Make static.
	* python/py-record-btrace.c (btpy_list_methods): Make static.
	* python/py-record.c (recpy_gap_type): Make static.
	* record.c (record_goto_cmdlist): Make static.
	* regcache.c (regcache_descr_handle): Make static.
	* registry.h (DEFINE_REGISTRY): Make definition static.
	* symmisc.c (std_in, std_out, std_err): Make static.
	* top.c (previous_saved_command_line): Make static.
	* tracepoint.c (trace_user, trace_notes, trace_stop_notes): Make
	static.
	* unittests/command-def-selftests.c (nr_duplicates,
	nr_invalid_prefixcmd, lists): Make static.
	* unittests/observable-selftests.c (test_notification): Make
	static.
	* unittests/optional/assignment/1.cc (counter): Make static.
	* unittests/optional/assignment/2.cc (counter): Make static.
	* unittests/optional/assignment/3.cc (counter): Make static.
	* unittests/optional/assignment/4.cc (counter): Make static.
	* unittests/optional/assignment/5.cc (counter): Make static.
	* unittests/optional/assignment/6.cc (counter): Make static.

gdbserver/ChangeLog:

	* ax.cc (bytecode_address_table): Make static.
	* debug.cc (debug_file): Make static.
	* linux-low.cc (stopping_threads): Make static.
	(step_over_bkpt): Make static.
	* linux-x86-low.cc (amd64_emit_ops, i386_emit_ops): Make static.
	* tracepoint.cc (stop_tracing_bkpt, flush_trace_buffer_bkpt,
	alloced_trace_state_variables, trace_buffer_ctrl,
	tracing_start_time, tracing_stop_time, tracing_user_name,
	tracing_notes, tracing_stop_note): Make static.

Change-Id: Ic1d8034723b7802502bda23770893be2338ab020
2021-01-20 20:55:05 -05:00
bdec2917b1 Convert some frame functions to use gdb::array_view.
This patch converts the most obvious functions from gdb/frame.h to use
the gdb::array_view abstraction.  I've converted the ones that used buffer +
length.

There are others using only the buffer, with an implicit size. I did not
touch those for now. But it would be nice to pass the size for safety.

Tested with --enable-targets=all on Ubuntu 18.04/20.04 aarch64-linux.

gdb/ChangeLog

2021-01-19  Luis Machado  <luis.machado@linaro.org>

	* frame.h (get_frame_register_bytes): Pass a gdb::array_view instead
	of buffer + length.
	(put_frame_register_bytes): Likewise.
	Adjust documentation.
	(get_frame_memory): Pass a gdb::array_view instead of buffer + length.
	(safe_frame_unwind_memory): Likewise.
	* frame.c (get_frame_register_bytes, put_frame_register_bytes)
	(get_frame_memory, safe_frame_unwind_memory): Adjust to use
	gdb::array_view.
	* amd64-fbsd-tdep.c (amd64fbsd_sigtramp_p): Likewise.
	* amd64-linux-tdep.c (amd64_linux_sigtramp_start): Likewise.
	* amd64-obsd-tdep.c (amd64obsd_sigtramp_p): Likewise.
	* arc-linux-tdep.c (arc_linux_is_sigtramp): Likewise.
	* cris-tdep.c (cris_sigtramp_start, cris_rt_sigtramp_start): Likewise.
	* dwarf2/loc.c (rw_pieced_value): Likewise.
	* hppa-tdep.c (hppa_frame_cache): Likewise.
	* i386-fbsd-tdep.c (i386fbsd_sigtramp_p): Likewise.
	* i386-gnu-tdep.c (i386_gnu_sigtramp_start): Likewise.
	* i386-linux-tdep.c (i386_linux_sigtramp_start)
	(i386_linux_rt_sigtramp_start): Likewise.
	* i386-obsd-tdep.c (i386obsd_sigtramp_p): Likewise.
	* i386-tdep.c (i386_register_to_value): Likewise.
	* i387-tdep.c (i387_register_to_value): Likewise.
	* ia64-tdep.c (ia64_register_to_value): Likewise.
	* m32r-linux-tdep.c (m32r_linux_sigtramp_start)
	(m32r_linux_rt_sigtramp_start): Likewise.
	* m68k-linux-tdep.c (m68k_linux_pc_in_sigtramp): Likewise.
	* m68k-tdep.c (m68k_register_to_value): Likewise.
	* mips-tdep.c (mips_register_to_value)
	(mips_value_to_register): Likewise.
	* ppc-fbsd-tdep.c (ppcfbsd_sigtramp_frame_sniffer)
	(ppcfbsd_sigtramp_frame_cache): Likewise.
	* ppc-obsd-tdep.c (ppcobsd_sigtramp_frame_sniffer)
	(ppcobsd_sigtramp_frame_cache): Likewise.
	* rs6000-tdep.c (rs6000_in_function_epilogue_frame_p)
	(rs6000_register_to_value): Likewise.
	* tilegx-tdep.c (tilegx_analyze_prologue): Likewise.
	* tramp-frame.c (tramp_frame_start): Likewise.
	* valops.c (value_assign): Likewise.
2021-01-19 14:42:23 -03:00
3666a04883 Update copyright year range in all GDB files
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.
2021-01-01 12:12:21 +04:00