Jan Kratochvil [Wed, 3 Nov 2021 10:29:18 +0000 (11:29 +0100)]
Fix LD_PRELOAD=/usr/lib64/libasan.so.6 gdb
Currently for a binary compiled normally (without -fsanitize=address) but with
LD_PRELOAD of ASAN one gets:
$ ASAN_OPTIONS=detect_leaks=0:alloc_dealloc_mismatch=1:abort_on_error=1:fast_unwind_on_malloc=0 LD_PRELOAD=/usr/lib64/libasan.so.6 gdb
=================================================================
==1909567==ERROR: AddressSanitizer: alloc-dealloc-mismatch (malloc vs operator delete []) on 0x602000001570
#0 0x7f1c98e5efa7 in operator delete[](void*) (/usr/lib64/libasan.so.6+0xb0fa7)
...
0x602000001570 is located 0 bytes inside of 2-byte region [0x602000001570,0x602000001572)
allocated by thread T0 here:
#0 0x7f1c98e5cd1f in __interceptor_malloc (/usr/lib64/libasan.so.6+0xaed1f)
#1 0x557ee4a42e81 in operator new(unsigned long) (/usr/libexec/gdb+0x74ce81)
SUMMARY: AddressSanitizer: alloc-dealloc-mismatch (/usr/lib64/libasan.so.6+0xb0fa7) in operator delete[](void*)
==1909567==HINT: if you don't care about these errors you may set ASAN_OPTIONS=alloc_dealloc_mismatch=0
==1909567==ABORTING
Despite the code called properly operator new[] and operator delete[].
But GDB's new-op.cc provides its own operator new[] which gets translated into
malloc() (which gets recogized as operatore new(size_t)) but as it does not
translate also operators delete[] Address Sanitizer gets confused.
The question is how many variants of the delete operator need to be provided.
There could be 14 operators new but there are only 4, GDB uses 3 of them.
There could be 16 operators delete but there are only 6, GDB uses 2 of them.
It depends on libraries and compiler which of the operators will get used.
Currently being used:
U operator new[](unsigned long)
U operator new(unsigned long)
U operator new(unsigned long, std::nothrow_t const&)
U operator delete[](void*)
U operator delete(void*, unsigned long)
Alan Modra [Wed, 3 Nov 2021 05:51:42 +0000 (16:21 +1030)]
asan: dlltool buffer overflow: embedded NUL in string
yyleng gives the pattern length, xstrdup just copies up to the NUL.
So it is quite possible writing at an index of yyleng-2 overflows
the xstrdup allocated string buffer. xmemdup quite handily avoids
this problem, even writing the terminating NUL over the trailing
quote. Use it in ldlex.l too where we'd already had a report of this
problem and fixed it by hand, and to implement xmemdup0 in gas.
binutils/
* deflex.l (single and double quote strings): Use xmemdup.
gas/
* as.h (xmemdup0): Use xmemdup.
ld/
PR 20906
* ldlex.l (double quote string): Use xmemdup.
Mike Frysinger [Wed, 3 Nov 2021 05:17:17 +0000 (01:17 -0400)]
sim: mloop: mark a few conditionally used funcs as unused
These are marked inline, so building w/gcc at higher optimization
levels will automatically discard them. But building with -O0 will
trigger unused function warnings, so fix that.
The common before/after cover functions in the common mloop generator
are not used by all architecture ports. Doesn't seem to be a hard
requirement, so marking them optional (i.e. unused) is fine.
The cris execute function is conditionally used depending on the
fast-build mode settings, so mark it unused too.
Alan Modra [Wed, 3 Nov 2021 04:20:18 +0000 (14:50 +1030)]
asan: assert (addr_ranges) <= (start)
That assert would be more obvious if it were reported as
"addr_ranges <= end_ranges". Fix that by using the obvious variable
in the final loop. Stop the assertion by using a signed comparison:
It's possible for the rounding up of the arange pointer to exceed the
end of the block when the block size is fuzzed.
* dwarf.c (display_debug_aranges): Use "end_ranges" in loop
displaying ranges rather that "start". Simplify rounding up
to 2*address_size boundary. Use signed comparison in loop.
Mike Frysinger [Sun, 31 Oct 2021 09:11:34 +0000 (05:11 -0400)]
opcodes: d10v: simplify header includes
This file doesn't use anything from bfd (sysdep.h), so drop that
include. This avoids an implicit dependency on the generated
config.h which can be problematic for build-time tools.
Also swap stdio.h for stddef.h. This file isn't doing or using
any I/O structures, but it does need NULL.
Alan Modra [Tue, 2 Nov 2021 08:31:06 +0000 (19:01 +1030)]
PR28523, ld.bfd created undefined symbols on ppc64
This patch removes any fake (linker created) function descriptor
symbol if its code entry symbol isn't dynamic, to ensure bogus dynamic
symbols are not created. The change to func_desc_adjust requires that
it be run only once, which means ppc64_elf_tls_setup can't call it for
just a few selected symbols.
PR 28523
* elf64-ppc.c (func_desc_adjust): If a function entry sym is
not dynamic and has no plt entry, hide any associated fake
function descriptor symbol.
(ppc64_elf_edit): Move func_desc_adjust iteration over syms to..
(ppc64_elf_tls_setup): ..here.
Tom de Vries [Tue, 2 Nov 2021 18:08:49 +0000 (19:08 +0100)]
[gdb/tdep, rs6000] Don't skip system call in skip_prologue
I ran into a case where a breakpoint on _exit never triggered, because it was
set past the end of the _exit prologue, past the end of the exit_group system
call (which does not return).
More concretely, the breakpoint was set at the last insn show here:
...
Dump of assembler code for function _exit:
0x00007ffff7e42ea0 <+0>: 12 00 4c 3c addis r2,r12,18
0x00007ffff7e42ea4 <+4>: 60 43 42 38 addi r2,r2,17248
0x00007ffff7e42ea8 <+8>: 00 00 00 60 nop
0x00007ffff7e42eac <+12>: f8 ff e1 fb std r31,-8(r1)
0x00007ffff7e42eb0 <+16>: 78 1b 7f 7c mr r31,r3
0x00007ffff7e42eb4 <+20>: f0 ff c1 fb std r30,-16(r1)
0x00007ffff7e42eb8 <+24>: ea 00 00 38 li r0,234
0x00007ffff7e42ebc <+28>: a0 8b 22 e9 ld r9,-29792(r2)
0x00007ffff7e42ec0 <+32>: 78 fb e3 7f mr r3,r31
0x00007ffff7e42ec4 <+36>: 14 6a c9 7f add r30,r9,r13
0x00007ffff7e42ec8 <+40>: 02 00 00 44 sc
0x00007ffff7e42ecc <+44>: 26 00 00 7c mfcr r0
0x00007ffff7e42ed0 <+48>: 00 10 09 74 andis. r9,r0,4096
...
Fix this by treating system calls the same as branches in skip_prologue:
by default, don't skip, such that the breakpoint is set at 0x00007ffff7e42eb8
instead.
Tom de Vries [Tue, 2 Nov 2021 17:55:32 +0000 (18:55 +0100)]
[gdb/testsuite] Handle SIGILL in two gdb.arch powerpc test-cases
On powerpc64le-linux, with test-case gdb.arch/powerpc-addpcis.exp I run into
SIGILL:
...
(gdb) PASS: gdb.arch/powerpc-addpcis.exp: get hexadecimal valueof "$r3"
stepi^M
^M
Program terminated with signal SIGILL, Illegal instruction.^M
The program no longer exists.^M
(gdb) PASS: gdb.arch/powerpc-addpcis.exp: set r4
...
because it's a power9 insn, and I'm running on a power8 machine.
Fix this by handling the SIGILL. Likewise in gdb.arch/powerpc-lnia.exp.
Bruno Larsen [Wed, 13 Oct 2021 12:43:13 +0000 (09:43 -0300)]
[gdb/doc]: Updated manpages to be consistent with help
Updated manpages to be consistent with help information provided by the
binary. The main changes are:
* Making all long-form options have '--', instead of a single '-';
* added most of the missing options to the manpage;
* removed the information about using '+' instead of '-', since it
doesn't seem to be supported anymore.
This also fixes 2 upstream bugs:
* https://sourceware.org/bugzilla/show_bug.cgi?id=23965; by adding
--args to the manpage
* https://sourceware.org/bugzilla/show_bug.cgi?id=10619; by adding the
double dashes
Alan Modra [Sun, 31 Oct 2021 13:50:01 +0000 (00:20 +1030)]
objcopy buffer overflow
"tocopy" in this code was an int, which when the size to be copied was
larger than MAXINT could result in tocopy being negative. A negative
value of course is less than BUFSIZE, but when converted to
bfd_size_type is extremely large.
PR 995
* objcopy.c (copy_unknown_object): Correct calculation of "tocopy".
Use better variable types.
Update also include:
+ New value of Tag_CPU_arch EABI attribute (22) is added.
+ Updated missing Tag_CPU_arch EABI attributes.
+ Updated how we combine archs 'v4t_plus_v6_m' as this mechanism
have to handle new Armv9 as well.
Regression tested on `arm-none-eabi` cross Binutils and no issues.
bfd/
* archures.c: Define bfd_mach_arm_9.
* bfd-in2.h (bfd_mach_arm_9): Define bfd_mach_arm_9.
* cpu-arm.c: Add 'armv9-a' option to -march.
* elf32-arm.c (using_thumb2_bl): Update assert check.
(arch_has_arm_nop): Add TAG_CPU_ARCH_V9.
(bfd_arm_get_mach_from_attributes): Add case for TAG_CPU_ARCH_V9.
Update assert.
(tag_cpu_arch_combine): Updated table.
(v9): New table..
binutils/
* readelf.c (arm_attr_tag_CPU_arch): Update with
elfcpp/
* arm.h: Update TAG_CPU_ARCH_ enums with correct values.
gas/
* NEWS: Update docs.
* config/tc-arm.c (get_aeabi_cpu_arch_from_fset): Return Armv9-a
for -amarch=all.
(aeabi_set_public_attributes): Update assert.
* doc/c-arm.texi: Update docs.
* testsuite/gas/arm/armv9-a_arch.d: New test.
* testsuite/gas/arm/attr-march-all.d: Update test with v9.
include/
* elf/arm.h Update TAG_CPU_ARCH_ defines with correct values.
* opcode/arm.h (ARM_EXT3_V9A): New macro.
(ARM_ARCH_NONE): Updated with arm_feature_set.core size.
(FPU_NONE): Updated.
(ARM_ANY): Updated.
(ARM_ARCH_UNKNOWN): New macro.
(ARM_FEATURE_LOW): Updated.
(ARM_FEATURE_CORE): Updated.
(ARM_FEATURE_CORE_LOW): Updated.
(ARM_FEATURE_CORE_HIGH): Updated.
(ARM_FEATURE_COPROC): Updated.
(ARM_FEATURE): Updated.
(ARM_FEATURE_ALL): New macro.
opcodes/
* arm-dis.c (select_arm_features): Support bfd_mach_arm_9.
Also Update bfd_mach_arm_unknown to use new macro ARM_ARCH_UNKNOWN.
Mike Frysinger [Mon, 1 Nov 2021 04:58:05 +0000 (00:58 -0400)]
sim: iq2000: reduce -Wno-error scope
Clean up the warnings in sim-if, then reduce the -Werror disable to
the files that still aren't clean that now that we require GNU make
and can set variables on a per-object basis.
Mike Frysinger [Mon, 1 Nov 2021 04:56:52 +0000 (00:56 -0400)]
sim: lm32: reduce -Wno-error scope
Clean up some warnings in dv-lm32cpu, and all in sim-if, then reduce
the -Werror disable to the files that still aren't clean that now that
we require GNU make and can set variables on a per-object basis.
Mike Frysinger [Mon, 1 Nov 2021 04:56:35 +0000 (00:56 -0400)]
sim: frv: reduce -Wno-error scope
Only two files in here still generates warnings, so reduce the -Werror
disable to that now that we require GNU make and can set variables on
a per-object basis.
Mike Frysinger [Mon, 1 Nov 2021 04:56:08 +0000 (00:56 -0400)]
sim: m32r: reduce -Wno-error scope
Only two files in here still generates warnings, so reduce the -Werror
disable to that now that we require GNU make and can set variables on
a per-object basis.
Mike Frysinger [Mon, 1 Nov 2021 04:55:27 +0000 (00:55 -0400)]
sim: mips: reduce -Wno-error scope
Fix a few printf warnings in sim-main.c, and then we're left with only
one file in here still generating warnings, so reduce the -Werror
disable to that alone now that we require GNU make and can set variables
on a per-object basis.
Mike Frysinger [Mon, 1 Nov 2021 04:55:02 +0000 (00:55 -0400)]
sim: erc32: reduce -Wno-error scope
Only one file in here still generates warnings, so reduce the -Werror
disable to that alone now that we require GNU make and can set variables
on a per-object basis.
Mike Frysinger [Mon, 1 Nov 2021 04:54:36 +0000 (00:54 -0400)]
sim: cris: reduce -Wno-error scope
Only two files in here still generates warnings, so reduce the -Werror
disable to that now that we require GNU make and can set variables on
a per-object basis.
Mike Frysinger [Mon, 1 Nov 2021 04:53:38 +0000 (00:53 -0400)]
sim: sh: reduce -Wno-error scope
Only one file in here still generates warnings, so reduce the -Werror
disable to that alone now that we require GNU make and can set variables
on a per-object basis.
Mike Frysinger [Mon, 1 Nov 2021 04:07:15 +0000 (00:07 -0400)]
sim: m68hc11: clean up pointer casts
The void *data field is used to past arbitrary data between event
handlers, and these are using it to pass an integer. Fix up the
casts to avoid using (long) to cast to/from pointers since there
is no guarantee that's the right size.
Mike Frysinger [Mon, 1 Nov 2021 03:48:16 +0000 (23:48 -0400)]
sim: ppc: switch core types to stdint.h types
There's no need to define these ourselves anymore, so switch to the
stdint.h types. This will be important when we start using PRI*
defines with printf formats.
Mike Frysinger [Mon, 1 Nov 2021 03:21:36 +0000 (23:21 -0400)]
sim: mn10300: clean up pointer casts
The void *data field is used to past arbitrary data between event
handlers, and these are using it to pass an enum. Fix up the casts
to avoid using (long) to cast to/from pointers since there is no
guarantee that's the right size.
Tom Tromey [Fri, 29 Oct 2021 23:04:09 +0000 (17:04 -0600)]
Fix latent bug in DWARF test case
On my branch that replaces the DWARF psymtab reader,
dw2-stack-boundary.exp started failing. However, when I look at the
output in gdb.log, it is correct:
file /home/tromey/gdb/build/gdb/testsuite/outputs/gdb.dwarf2/dw2-stack-boundary/dw2-stack-boundary
Reading symbols from /home/tromey/gdb/build/gdb/testsuite/outputs/gdb.dwarf2/dw2-stack-boundary/dw2-stack-boundary...
During symbol reading: location description stack overflow
During symbol reading: location description stack underflow
What happens to cause the failure is that the two branches in
gdb_test_multiple appear in this order:
-re "\r\nDuring symbol reading: location description stack underflow" {
[...]
-re "\r\nDuring symbol reading: location description stack overflow" {
The first one will match the above, without causing the second one to
ever match -- leading to a spurious failure.
Anchoring the regexps seems to fix the problem, and works for the
current gdb as well.
Tom Tromey [Sun, 31 Oct 2021 17:34:06 +0000 (11:34 -0600)]
Fix unittest.exp failure due to 'set debuginfod' addition
The 'set debuginfod' change caused a regression in unittest.exp:
Running selftest help_doc_invariants.
help doc broken invariant: command 'info set debuginfod' help doc first line is not terminated with a '.' character
help doc broken invariant: command 'set debuginfod' help doc first line is not terminated with a '.' character
help doc broken invariant: command 'show debuginfod' help doc first line is not terminated with a '.' character
Self test failed: self-test failed at ../../binutils-gdb/gdb/unittests/command-def-selftests.c:100
Mike Frysinger [Wed, 7 Jul 2021 03:37:56 +0000 (23:37 -0400)]
sim: nltvals: pull target open flags out into a dedicated source file
Like we just did for pulling out the errno & signal maps, pull out the
open flag map into a dedicated common file. All newlib ports are using
the same map which makes it easy.
Mike Frysinger [Wed, 7 Jul 2021 03:21:20 +0000 (23:21 -0400)]
sim: nltvals: localize TARGET_<open> defines
Code should not be using these directly, instead they should be
resolving these dynamically via the open_map. Rework the common
callback code that was using the defines to use symbolic names
instead, and localize some of the defines in the ARM code (since
it's a bit unclear how many different APIs it supports currently),
then remove the defines out of the header so no new code can rely on
them.
Mike Frysinger [Wed, 7 Jul 2021 02:43:10 +0000 (22:43 -0400)]
sim: nltvals: pull target signal out into a dedicated source file
Like we just did for pulling out the errno map, pull out the signal
map into a dedicated common file. All newlib ports are using the
same signal map which makes it easy.
Mike Frysinger [Wed, 7 Jul 2021 02:10:53 +0000 (22:10 -0400)]
sim: nltvals: pull target errno out into a dedicated source file
The current system maintains a list of target errno constants in the
nltvals.def file, then runs a build-time tool to turn that into a C
file. This list of errno values is the same for all arches, so we
don't need the arch-specific flexibility. Further, these are only
for newlib/libgloss environments, which makes it confusing to support
other userland runtimes (like Linux). Let's simplify to make this
easier to understand & build. We don't namespace the variables yet,
but sets up the framework for it.
Create a new target-newlib-errno.c template file. The template file
is hand written, but the inline map is still automatically generated.
This allows us to move it to the common set of objects so it's only
built once in a multi-target build.
Now we can remove the output from the gentmap build-time tool since
it's checked into the tree.
Then we stop including the errno lists in nltvals.def since nothing
uses it.
Mike Frysinger [Sun, 31 Oct 2021 04:55:50 +0000 (00:55 -0400)]
sim: igen: tighten up build output
Add a new stamp helper for quiet builds, and don't dump the command
line options when it runs. That isn't standard tool behavior, and
doesn't really seem necessary in any way.
Orgad Shaneh [Thu, 28 Oct 2021 09:07:46 +0000 (09:07 +0000)]
sim: fix compilation on mingw64 [PR sim/28476]
...by reordering includes.
1. sim-utils.c
sim/mips/sim-main.h defines UserMode, while there is a struct in winnt.h
which has UserMode as a member. So if sim-main.h is included before winnt.h,
compilation fails.
2. ppc
registers.h defines CR, which is used as a member in winnt.h.
winsock2.h is included by sys/time.h, so sys/time.h has to be included
before registers.h.
Alan Modra [Sat, 30 Oct 2021 23:38:15 +0000 (10:08 +1030)]
Don't include coff/pe.h in coff-x86_64.c
This (and other) code from coffcode.h is broken for x86_64_coff_vec,
and has been ever since support was added in 2006 commit 99ad839030c1
Here, bfd_coff_aoutsz must match coff_swap_aouthdr_out otherwise we
end up writing garbage.
/* Note that peicode.h fills in a PEAOUTHDR, not an AOUTHDR.
include/coff/pe.h sets AOUTSZ == sizeof (PEAOUTHDR)). */
char * buff;
bfd_size_type amount = bfd_coff_aoutsz (abfd);
We have removed support for --target=x86_64-coff, likely because it
never worked properly, but still produce coff-x86_64.o with
--enable-targets=all. This means objcopy can recognize x86_64 COFF
files but will write garbage to the output file, a fact found by
fuzzers. I suspect x86_64 COFF is still broken after this fix, and
mention of coff-x86_64.* should be removed from bfd/Makefile.am.
* coff-x86_64.c: Don't include coff/pe.h.
(COFF_WITH_pex64): Don't define here.
* pe-x86_64.c: Include coff/pe.h and other headers.
(PEI_HEADERS): Define.
That's because when compiling with C++ >= 17, we use the standard
version of string_view, and don't have a selftest for it. So the list
of selftests shown by the tab completion when completing "string_v"
differs.
Aaron Merey [Fri, 29 Oct 2021 23:55:57 +0000 (19:55 -0400)]
gdb: add set/show commands for managing debuginfod
Add 'set debuginfod' command. Accepts 'on', 'off' or 'ask' as an
argument. 'on' enables debuginfod for the current session. 'off'
disables debuginfod for the current session. 'ask' will prompt
the user to either enable or disable debuginfod when the next query
is about to be performed:
This GDB supports auto-downloading debuginfo from the following URLs:
<URL1> <URL2> ...
Enable debuginfod for this session? (y or [n]) y
Debuginfod has been enabled.
To make this setting permanent, add 'set debuginfod on' to .gdbinit.
For interactive sessions, 'ask' is the default. For non-interactive
sessions, 'off' is the default.
Add 'show debuginfod status' command. Displays whether debuginfod
is set to 'on', 'off' or 'ask'.
Add 'set/show debuginfod urls' commands. Accepts a string of
space-separated debuginfod server URLs to be queried. The default
value is copied from the DEBUGINFOD_URLS environment variable.
Finally add 'set/show debuginfod verbose' commands to control whether
debuginfod-related output is displayed. Verbose output is enabled
by default.
(gdb) run
Starting program: /bin/sleep 5
Download failed: No route to host. Continuing without debug info for /lib64/libc.so.6.
If GDB is not built with debuginfod then these commands will just display
Tom Tromey [Fri, 22 Oct 2021 16:49:19 +0000 (10:49 -0600)]
Add gdb.Architecture.integer_type Python function
This adds a new Python function, gdb.Architecture.integer_type, which
can be used to look up an integer type of a given size and
signed-ness. This is useful to avoid dependency on debuginfo when a
particular integer type would be useful.
v2 moves this to be a method on gdb.Architecture and addresses other
review comments.
Tom Tromey [Wed, 20 Oct 2021 20:25:21 +0000 (14:25 -0600)]
Remove ada_value_print_inner
I noticed that the only caller of ada_value_print_inner is
valprint.c:do_val_print (via ada_language::value_print_inner), meaning
that the try/catch logic in this function is redundant. This patch
removes the wrapper function.
Tom Tromey [Tue, 19 Oct 2021 20:42:04 +0000 (14:42 -0600)]
Document resolve_dynamic_type oddity
Today I re-learned that resolve_dynamic_type can return a type for
which is_dynamic_type returns true. This can happen for an array
whose elements have dynamic type -- the array is reported as dynamic,
but resolving the elements would be incorrect, because each element
might have a different type after resolution.
You can see the special case in resolve_dynamic_array_or_string:
I looked into having the TYPE_CODE_ARRAY case in
is_dynamic_type_internal follow this same logic, but that breaks down
on the gdb.fortran/dynamic-ptype-whatis.exp test case. In particular
this code in fortran_undetermined::evaluate:
... relies on is_dynamic_type returning true for such an array.
I wasn't really sure of the best way to fix this, so in the meantime I
wrote this patch, which documents the oddity so that I might have a
chance of remembering this in the future.
Tom Tromey [Wed, 29 Sep 2021 16:14:52 +0000 (10:14 -0600)]
Avoid self-test failures on x86-linux
The disassembly tests in "maint selftest" will fail on x86-linux.
This happens because opcodes rejects an attempt to disassemble for an
arch with a 64-bit address size when bfd_vma is 32-bit.
This patch avoids this problem by avoiding the test in this case. I
chose to do it this way because this seems to be the only situation
where opcodes checks the size of bfd_vma.
For v2 of this patch, I've also updated memory_error_test to do the
same thing. This is needed due to the "improve error reporting from
the disassembler" patch.
Tom de Vries [Fri, 29 Oct 2021 12:11:08 +0000 (14:11 +0200)]
[gdb/build] Fix build with --disable-unit-tests
A build with --disable-unit-tests currently run into:
...
ld: maint.o: in function \
`maintenance_selftest_completer(cmd_list_element*, completion_tracker&,
char const*, char const*)':
src/gdb/maint.c:1183: undefined reference to \
`selftests::for_each_selftest(
gdb::function_view<
void (std::__cxx11::basic_string<char,std::char_traits<char>,
std::allocator<char> > const&)>)'
...
Fix this by guarding the call to selftests::for_each_selftest in
maintenance_selftest_completer with GDB_SELF_TEST, such that the "-verbose"
completion still works.
Rebuild on x86_64-linux and ran gdb.gdb/unittest.exp.
Tejas Belagod [Tue, 5 Oct 2021 08:43:12 +0000 (08:43 +0000)]
Support for a new pacbti unwind opcode.
This patch adds readelf support for decoding the exception table
opcode for restoring the RA_AUTH_CODE pseudo register defined by the
EHABI
(https://github.com/ARM-software/abi-aa/releases/download/2021Q1/ehabi32.pdf
Section 10.3).
* readelf.c (decode_arm_unwind_bytecode): Add support to decode
restoring RA_AUTH_CODE pseudo register.
Stafford Horne [Fri, 23 Oct 2020 04:39:53 +0000 (13:39 +0900)]
gdb: or1k: add single step for linux native debugging
Needed for single stepping in Linux, this adds the or1k implementation
of or1k_software_single_step. Most of the implementation is borrowed
from the bare metal single step code from or1k_single_step_through_delay
which has been extracted and shared in helper function
or1k_delay_slot_p.