| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
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.
|
|
The canonical form of 'if' in modern TCL is 'if {} {}'. But there's
still a bunch of places in the testsuite where we make use of the
'then' keyword, and sometimes these get copies into new tests, which
just spreads poor practice.
This commit removes all use of the 'then' keyword from the testsuite
library files (in boards/, config/, and lib/). Previous commits have
removed all uses of the 'then' keyword from the test script files,
this commit just cleans up the library files.
There should be no changes in what is tested after this commit.
|
|
When calling get_func_info inside a test case, it would cause failures
if the function was printed using a C++ style mangled name. The current
patch fixes this by allowing for mangled names along with the current
rules.
Approved-By: Tom Tromey <tom@tromey.com>
|
|
On openSUSE Tumbleweed I run into this for the dwarf assembly test-cases, and
some hardcoded assembly test-cases:
...
Running gdb.dwarf2/fission-absolute-dwo.exp ...
gdb compile failed, ld: warning: fission-absolute-dwo.o: \
missing .note.GNU-stack section implies executable stack
ld: NOTE: This behaviour is deprecated and will be removed in a future \
version of the linker
=== gdb Summary ===
# of untested testcases 1
...
Fix the dwarf assembly test-cases by adding the missing .note.GNU-stack in
proc Dwarf::assemble.
Fix the hard-coded test-cases using this command:
...
$ for f in $(find gdb/testsuite/gdb.* -name *.S); do
if ! grep -q note.GNU-stack $f; then
echo -e "\t.section\t.note.GNU-stack,\"\",@progbits" >> $f;
fi;
done
...
Likewise for .s files, and gdb/testsuite/lib/my-syscalls.S.
The idiom for arm seems to be to use %progbits instead, see commit 9a5911c08be
("gdb/testsuite/gdb.dwarf2: Replace @ with % for ARM compatability"), so
hand-edit gdb/testsuite/gdb.arch/arm-disp-step.S to use %progbits instead.
Note that dwarf assembly testcases use %progbits as decided by proc _section.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29674
|
|
With test-case gdb.dwarf2/macro-source-path.exp and target board unix/-m32, I
run into:
...
as: macro-source-path-gcc11-ld238-dw5-filename-641.o: \
unsupported relocation type: 0x1^M
...
The problem is that we have 64-bit dwarf so the debug_line offset in the
.debug_macro section is an 8-byte entity, emitted using ".8byte":
...
.section .debug_macro
.Lcu_macros4:
.2byte 5 /* version */
.byte 3 /* flags */
.8byte .LLlines3 /* debug_line offset */
...
but the linker doesn't support 8-byte relocation types on a 32-bit architecture.
This is similar to what was fixed in commit a5ac8e7fa3b
("[gdb/testsuite] Fix 64-bit dwarf test-cases with -m32") for for instance
.debug_abbrev.
Fix this in the same way, by using _op_offset to emit the debug_line offset.
Tested on x86_64-linux with native and target board unix/-m32.
|
|
Since commit 52b920c5d20 ("[gdb/testsuite] Fix gdb.dwarf2/dw2-dir-file-name.exp
for ppc64le"), the test-case fails with target board cc-with-debug-names, due
to missing .debug_aranges info.
Add the missing .debug_aranges info.
Also add a file_id option to Dwarf::assemble, to make it possible to contribute
to an already open file.
Tested on x86_64-linux.
|
|
When running test-case gdb.cp/cpexprs-debug-types.exp on target board
cc-with-debug-names/gdb:debug_flags=-gdwarf-5, we get an executable with
a .debug_names section, but no .debug_types section. For dwarf-5, the TUs
are no longer put in a separate unit, but instead they're put in the
.debug_info section.
When loading the executable, the .debug_names section is silently ignored
because of this check in dwarf2_read_debug_names:
...
if (map->tu_count != 0)
{
/* We can only handle a single .debug_types when we have an
index. */
if (per_bfd->types.size () != 1)
return false;
...
which triggers because per_bfd->types.size () == 0.
The intention of the check is to make sure we don't have more that one
.debug_types section, as can happen in a object file (see PR12984):
...
$ grep "\.debug_types" 11.s
.section .debug_types,"G",@progbits,wt.75c042c23a9a07ee,comdat
.section .debug_types,"G",@progbits,wt.c59c413bf50a4607,comdat
...
Fix this by:
- changing the check condition to "per_bfd->types.size () > 1", and
- handling per_bfd->types.size () == 0.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29385
|
|
Add test-case gdb.dwarf2/debug-names-bad-cu-index.exp, a regression test for
commit 2fe9a3c41fa ("[gdb/symtab] Fix bad compile unit index complaint").
Tested on x86_64-linux.
|
|
Add a test-case gdb.dwarf2/debug-names-tu.exp, that uses the dwarf assembler
to specify a .debug_names index with the TU list referring to a TU from the
.debug_types section.
This is intended to produce something similar to:
...
$ gcc -g -fdebug-types-section ~/hello.c -gdwarf-4
$ gdb-add-index -dwarf-5 a.out
...
Tested on x86_64-linux.
|
|
When writing a dwarf testcase for some C++ code I wanted to use the
MACRO_AT_range which in turn uses the function_range proc in dwarf.exp
to extract the bounds of 'main'.
However, the macro failed as GDB prints the C++ 'main' with its
arguments as 'main(int, char**)' or 'main()'.
The reason for this is that in read.c::dwarf2_compute_name we call
c_type_print_args on C++ functions and append their arguments to the
function name. This happens to all C++ functions, but is only visible
when the function doesn't have a linkage name.
An example might make this more clear. Given the following code
>> cat c.cpp
int foo (int a, float b)
{
return 0;
}
int main (int argc, char **argv)
{
return 0;
}
which is legal in both languages, C and C++, and compiling it with
e.g. clang or gcc will make the disassemble command look like:
>> clang --version
clang version 10.0.0-4ubuntu1
...
>> clang -O0 -g ./c.cpp
>> gdb -q ./a.out -ex "start"
...
(gdb) disassemble main
Dump of assembler code for function main(int, char**):
0x0000000000401120 <+0>: push %rbp
0x0000000000401121 <+1>: mov %rsp,%rbp
...
0x0000000000401135 <+21>: ret
End of assembler dump.
(gdb) disassemble foo
Dump of assembler code for function _Z3fooif:
0x0000000000401110 <+0>: push %rbp
0x0000000000401111 <+1>: mov %rsp,%rbp
...
0x000000000040111f <+15>: ret
End of assembler dump.
Note, that main is emitted with its arguments while for foo the linkage
name is being printed, as also visible in its DWARF:
>> objdump ./a.out --dwarf=info | grep "foo" -A3 -B3
<2b> DW_AT_low_pc : 0x401110
<33> DW_AT_high_pc : 0x10
<37> DW_AT_frame_base : 1 byte block: 56 (DW_OP_reg6 (rbp))
<39> DW_AT_linkage_name: (indirect string, offset: 0x39): _Z3fooif
<3d> DW_AT_name : (indirect string, offset: 0x42): foo
<41> DW_AT_decl_file : 1
<42> DW_AT_decl_line : 1
<43> DW_AT_type : <0x9a>
Now, let's rename the C++ file and compile it as C:
>> mv c.cpp c.c
>> clang -O0 -g ./c.c
>> gdb -q ./a.out -ex "start'
...
(gdb) disassemble main
Dump of assembler code for function main:
0x0000000000401120 <+0>: push %rbp
0x0000000000401121 <+1>: mov %rsp,%rbp
...
0x0000000000401135 <+21>: ret
End of assembler dump.
(gdb) disassemble foo
Dump of assembler code for function foo:
0x0000000000401110 <+0>: push %rbp
0x0000000000401111 <+1>: mov %rsp,%rbp
...
0x000000000040111f <+15>: ret
End of assembler dump.
Note, for foo we did not get a linkage name emitted in DWARF, so
it is printed by its name:
>> objdump --dwarf=info ./a.out | grep foo -A3 -B3
<2b> DW_AT_low_pc : 0x401110
<33> DW_AT_high_pc : 0x10
<37> DW_AT_frame_base : 1 byte block: 56 (DW_OP_reg6 (rbp))
<39> DW_AT_name : (indirect string, offset: 0x37): foo
<3d> DW_AT_decl_file : 1
<3e> DW_AT_decl_line : 1
<3f> DW_AT_prototyped : 1
To make the macro and proc work with C++ as well, an optional argument
list was added to the regex matching the function name in the
disassemble command in function_range. This does not change any used
behavior as currently, there exists no C++ test using the proc
function_range.
Signed-off-by: Nils-Christian Kempke <nils-christian.kempke@intel.com>
|
|
Add:
- support for a per-module .debug_names section in the dwarf assembler, and
- a test-case excercising this new functionality.
A per-module .debug_names section needs to have an entry in the CU list for
each CU in the module, which is made more difficult by two things:
- linking in other objects, which may contain additional CUs
(typically the case on openSUSE), and
- adding dummy CUs in the dwarf assembler.
We handle this by:
- compiling with -nostartfiles (so the test-case contains _start rather than
main), and
- disabling the dummy CU generation for the test-case.
I've kept things simple by having the test-case specify the hash value, rather
than adding that functionality in the dwarf assembler.
Also I've kept the bucket count to 1, which makes it trivial to satisfy the
requirement that "the symbol is entered into a bucket whose index is the hash
value modulo bucket_count".
The readelf dump of the .debug_names section from the test-case looks like:
...
Version 5
Augmentation string: 47 44 42 00 ("GDB")
CU table:
[ 0] 0x0
TU table:
Foreign TU table:
Used 1 of 1 bucket.
Out of 2 items there are 1 bucket clashes (longest of 1 entries).
Symbol table:
[ 0] #eddb6232 _start: <1> DW_TAG_subprogram DW_IDX_compile_unit=0
[ 1] #0b888030 int: <2> DW_TAG_base_type DW_IDX_compile_unit=0
...
Tested on x86_64-linux.
|
|
Using different ways of passing source file paths to compilers results n
different file and directory paths in the line header. For example:
- gcc foo.c
- gcc ./foo.c
- gcc ../cwd/foo.c
- gcc $PWD/foo.c
Because of this, GDB sometimes failed to look up macros. The previous
patch fixed that as much as possible. This patch adds the corresponding
tests.
Add both a DWARF assembler-based test and a regular test. The DWARF
assembled-based one tests some hard-coded debug info based on what I
have observed some specific versions of gcc and clang generate. We want
to make sure that GDB keeps handling all these cases correctly, even if
it's not always clear whether they are really valid DWARF. Also, they
will be tested no matter what the current target compiler is for a given
test run.
The regular test is compiled using the target compiler, so it may help
find bugs when testing against some other toolchains than what was used
to generate the DWARF assembler-based test.
For the DWARF assembler-based test, add to testsuite/lib/dwarf.exp the
necessary code to generate a DWARF5 .debug_macro section. The design of
the new procs is based on what was done for rnglists and loclists.
To test against a specific compiler one can use this command, for
example:
$ make check TESTS="gdb.base/macro-source-path.exp" RUNTESTFLAGS="CC_FOR_TARGET=clang --target_board unix/gdb:debug_flags=-gdwarf-5"
Change-Id: Iab8da498e57d10cc2a3d09ea136685d9278cfcf6
|
|
We don't need to call get_compiler_info before calling
test_compiler_info; test_compiler_info includes a call to
get_compiler_info.
This commit cleans up lib/gdb.exp and lib/dwarf.exp a little by
removing some unneeded calls to get_compiler_info. We could do the
same cleanup throughout the testsuite, but I'm leaving that for
another day.
There should be no change in the test results after this commit.
|
|
When running test-case gdb.dwarf2/locexpr-data-member-location.exp with
target board unix/-fno-PIE/-no-pie/-m32 I run into:
...
(gdb) step^M
26 return 0;^M
(gdb) FAIL: gdb.dwarf2/locexpr-data-member-location.exp: step into foo
...
The problem is that the test-case tries to mimic some gdb_compile_shlib
behaviour using:
...
set flags {additional_flags=-fpic debug}
get_func_info foo $flags
...
but this doesn't work with the target board setting, because we end up doing:
...
gcc locexpr-data-member-location-lib.c -fpic -g -lm -fno-PIE -no-pie -m32 \
-o func_addr23029.x
...
while gdb_compile_shlib properly filters out the -fno-PIE -no-pie.
Consequently, the address for foo determined by get_func_info doesn't match
the actual address of foo.
Fix this by printing the address of foo using the result of gdb_compile_shlib.
|
|
DWARF 5
To support DWARF 5 in the DWARF assembler line tables, we currently copy
the first user-provided directory and the first user-provided files and
make them elements at indices 0 in the directory and file name tables.
That was a sufficient behavior at the time (see commit 44fda089397a
("[gdb/testsuite] Support .debug_line v5 in dwarf assembler")), but in
the following patches, I would need to have finer grained control on
what is generated exactly. For example, I'd like to generate a DWARF 5 line
table with just a single file and a single directory.
Get rid of this behavior, and implement what is suggested in
44fda089397a: make include_dir return the directory index that can be
used to refer to that directory entry (based on the DWARF version), and
use it afterwards.
Adjust dw2-lines.exp and dw2-prologue-end.exp accordingly. Their produced
DWARF5 binaries will change a bit, in that they will now have a single
directory and file, where they had two before. But it doesn't change
the expected GDB behavior.
Change-Id: I5459b16ac9b7f28c34c9693c35c9afd2ebb3aa3b
|
|
By calling `uplevel $body` in the program proc (a pattern we use at many
places), we can get rid of curly braces around each line number program
directive. That seems like a nice small improvement to me.
Change-Id: Ib327edcbffbd4c23a08614adee56c12ea25ebc0b
|
|
These variables seem to be unused, remove them.
Change-Id: I7d613d9d35735930ee78b2c348943c73a702afbb
|
|
Add support for DW_LNS_set_prologue_end when building line-tables. This
attribute can be set by the compiler to indicate that an instruction is
an adequate place to set a breakpoint just after the prologue of a
function.
The compiler might set multiple prologue_end, but considering how
current skip_prologue_using_sal works, this commit modifies it to accept
the first instruction with this marker (if any) to be the place where a
breakpoint should be placed to be at the end of the prologue.
The need for this support came from a problematic usecase generated by
hipcc (i.e. clang). The problem is as follows: There's a function
(lets call it foo) which covers PC from 0xa800 to 0xa950. The body of
foo begins with a call to an inlined function, covering from 0xa800 to
0xa94c. The issue is that when placing a breakpoint at 'foo', GDB
inserts the breakpoint at 0xa818. The 0x18 offset is what GDB thinks is
foo's first address past the prologue.
Later, when hitting the breakpoint, GDB reports the stop within the
inlined function because the PC falls in its range while the user
expects to stop in FOO.
Looking at the line-table for this location, we have:
INDEX LINE ADDRESS IS-STMT
[...]
14 293 0x000000000000a66c Y
15 END 0x000000000000a6e0 Y
16 287 0x000000000000a800 Y
17 END 0x000000000000a818 Y
18 287 0x000000000000a824 Y
[...]
For comparison, let's look at llvm-dwarfdump's output for this CU:
Address Line Column File ISA Discriminator Flags
------------------ ------ ------ ------ --- ------------- -------------
[...]
0x000000000000a66c 293 12 2 0 0 is_stmt
0x000000000000a6e0 96 43 82 0 0 is_stmt
0x000000000000a6f8 102 18 82 0 0 is_stmt
0x000000000000a70c 102 24 82 0 0
0x000000000000a710 102 18 82 0 0
0x000000000000a72c 101 16 82 0 0 is_stmt
0x000000000000a73c 2915 50 83 0 0 is_stmt
0x000000000000a74c 110 1 1 0 0 is_stmt
0x000000000000a750 110 1 1 0 0 is_stmt end_sequence
0x000000000000a800 107 0 1 0 0 is_stmt
0x000000000000a800 287 12 2 0 0 is_stmt prologue_end
0x000000000000a818 114 59 81 0 0 is_stmt
0x000000000000a824 287 12 2 0 0 is_stmt
0x000000000000a828 100 58 82 0 0 is_stmt
[...]
The main difference we are interested in here is that llvm-dwarfdump's
output tells us that 0xa800 is an adequate place to place a breakpoint
past a function prologue. Since we know that foo covers from 0xa800 to
0xa94c, 0xa800 is the address at which the breakpoint should be placed
if the user wants to break in foo.
This commit proposes to add support for the prologue_end flag in the
line-program processing.
The processing of this prologue_end flag is made in skip_prologue_sal,
before it calls gdbarch_skip_prologue_noexcept. The intent is that if
the compiler gave information on where the prologue ends, we should use
this information and not try to rely on architecture dependent logic to
guess it.
The testsuite have been executed using this patch on GNU/Linux x86_64.
Testcases have been compiled with both gcc/g++ (verison 9.4.0) and
clang/clang++ (version 10.0.0) since at the time of writing GCC does not
set the prologue_end marker. Tests done with GCC 11.2.0 (not over the
entire testsuite) show that it does not emit this flag either.
No regression have been observed with GCC or Clang. Note that when
using Clang, this patch fixes a failure in
gdb.opt/inline-small-func.exp.
Change-Id: I720449a8a9b2e1fb45b54c6095d3b1e9da9152f8
|
|
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.
|
|
Proc lines contains a typo:
...
string_form { set $_line_string_form $value }
...
Remove the incorrect '$' in '$_line_string_form'.
Tested on x86_64-linux.
|
|
When running test-case gdb.dwarf2/dw2-lines.exp with target board -unix/-m32,
we run into another instance of PR28383, where the dwarf assembler generates
64-bit relocations which are not supported by the 32-bit assembler:
...
dw2-lines-dw.S: Assembler messages:^M
outputs/gdb.dwarf2/dw2-lines/dw2-lines-dw.S:76: Error: \
cannot represent relocation type BFD_RELOC_64^M
...
Fix this by using _op_offset in _line_finalize_header.
Tested on x86_64-linux.
|
|
I noticed a new gcc option -gdwarf64 and tried it out (using gcc 11.2.1).
With a test-case hello.c:
...
int
main (void)
{
printf ("hello\n");
return 0;
}
...
compiled like this:
...
$ gcc -g -gdwarf64 ~/hello.c
...
I ran into:
...
$ gdb -q -batch a.out
DW_FORM_line_strp pointing outside of .debug_line_str section \
[in module a.out]
...
Debugging gdb revealed that the string offset is:
...
(gdb) up
objfile=0x182ab70, str_offset=1378684502312,
form_name=0xeae9b5 "DW_FORM_line_strp")
at src/gdb/dwarf2/section.c:208
208 error (_("%s pointing outside of %s section [in module %s]"),
(gdb) p /x str_offset
$1 = 0x14100000128
(gdb)
...
which is read when parsing a .debug_line entry at 0x1e0.
Looking with readelf at the 0x1e0 entry, we have:
...
The Directory Table (offset 0x202, lines 2, columns 1):
Entry Name
0 (indirect line string, offset: 0x128): /data/gdb_versions/devel
1 (indirect line string, offset: 0x141): /home/vries
...
which in a hexdump looks like:
...
0x00000200 1f022801 00004101 00000201 1f020f02
...
What happens is the following:
- readelf interprets the DW_FORM_line_strp reference to .debug_line_str as
a 4 byte value, and sees entries 0x00000128 and 0x00000141.
- gdb instead interprets it as an 8 byte value, and sees as first entry
0x0000014100000128, which is too big so it bails out.
AFAIU, gdb is wrong. It assumes DW_FORM_line_strp is 8 bytes on the basis
that the corresponding CU is 64-bit DWARF. However, the .debug_line
contribution has it's own initial_length field, and encodes there that it's
32-bit DWARF.
Fix this by using the correct offset size for DW_FORM_line_strp references
in .debug_line.
Note: the described test-case does trigger this complaint (both with and
without this patch):
...
$ gdb -q -batch -iex "set complaints 10" a.out
During symbol reading: intermixed 32-bit and 64-bit DWARF sections
...
The reason that the CU has 64-bit dwarf is because -gdwarf64 was passed to
gcc. The reason that the .debug_line entry has 32-bit dwarf is because that's
what gas generates. Perhaps this is complaint-worthy, but I don't think it
is wrong.
Tested on x86_64-linux, using native and target board dwarf64.exp.
|
|
The v5 section version for .debug_line has:
- two new fields address_size and segment_selector_size
- a different way to encode the directory and filename tables.
Add support for this in the dwarf assembler.
For now, make the v5 directory and filename tables work with the v4 type of
specification in the test-cases by adding duplicate entries at position 0.
This will need to be properly fixed with an intrusive fix that changes how
directory and filename entries are specified in the test-cases, f.i:
...
set diridx [include_dir "${srcdir}/${subdir}"]
set fileidx [file_name "$srcfile" $diridx]
...
Tested on x86_64-linux.
|
|
Rather than generate dwarf immediately in procs include_dir and file_name,
postpone generation and store the data in variables. Then handle the
generation in a new proc _line_finalize_header.
Tested on x86-64-linux.
|
|
The .debug_line header got a new field in v4:
maximum_operations_per_instruction.
Generate this field in the dwarf assembler, for now hardcoding the value to 1,
meaning non-VLIW.
Tested on x86_64-linux.
|
|
Add a new test-case gdb.dwarf2/dw2-lines.exp that tests various .debug_line
sections.
Tested on x86_64-linux.
|
|
Currently, for each MACRO_AT_range or MACRO_AT_func in dwarf assembly the
following is done:
- $srcdir/$subdir/$srcfile is compiled to an executable using
flags "debug"
- a new gdb instance is started
- the new executable is loaded.
This is inefficient, because the executable is identical within the same
Dwarf::assemble call.
Share the gdb instance in the same Dwarf::assemble invocation, which speeds
up a make check with RUNTESTFLAGS like this to catch all dwarf assembly
test-cases:
...
rtf=$(echo $(cd src/gdb/testsuite; find gdb.* -type f -name "*.exp" \
| xargs grep -l Dwarf::assemble))
...
from:
...
real 1m39.916s
user 1m25.668s
sys 0m21.377s
...
to:
...
real 1m29.512s
user 1m17.316s
sys 0m19.100s
...
Tested on x86_64-linux.
|
|
When running test-case gdb.dwarf2/loc-sec-offset.exp with target board -m32,
I run into:
...
builtin_spawn -ignore SIGHUP gcc -fno-stack-protector -m32 \
-fdiagnostics-color=never -c -o loc-sec-offset-dw641.o \
loc-sec-offset-dw64.S^M
as: loc-sec-offset-dw641.o: unsupported relocation type: 0x1^M
loc-sec-offset-dw64.S: Assembler messages:^M
loc-sec-offset-dw64.S:29: Error: cannot represent relocation type \
BFD_RELOC_64^M
...
Looking at line 29, we have:
...
.8byte .Labbrev1_begin /* Abbrevs */
...
It would be nice if the assembler could handle this somehow. But I guess
it's not unreasonable that an assembler for a 32-bit architecture will object
to handling 64-bit labels.
Instead, work around this in the dwarf assembler by emitting:
...
.4byte .Labbrev1_begin /* Abbrevs (lsw) */
.4byte 0 /* Abbrevs (msw) */
...
Tested on x86_64-linux with target board unix/-m32.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28383
|
|
When the code to handle DW_LLE_start_end was added (as part of some
DWARF 5 work), it was written to add the base address. However, this
seems incorrect -- the DWARF standard describes this as an address,
not an offset from the base address.
This patch changes a couple of spots in dwarf2/loc.c to fix this
problem. It then changes decode_debug_loc_addresses to return
DEBUG_LOC_OFFSET_PAIR instead, which preserves the previous semantics.
This only showed up on the RISC-V target internally, due to the
combination of DWARF 5 and a newer version of GCC. I've updated a
couple of existing loclists test cases to demonstrate the bug.
|
|
Add .debug_loc support in the dwarf assembler, and use it in new test-case
gdb.dwarf2/loc-sec-offset.exp (which is based on
gdb.dwarf2/loclists-sec-offset.exp).
Tested on x86_64-linux.
|
|
Change how rnglists and loclists procs to align them with how procs for
aranges (and other things in the DWARF assembler) work. Instead of
using "args" (variable number of parameters in TCL) and command-line
style option arguments, use one leading "option" parameters, used as a
kind of key/value dictionary of options parsed using `parse_options`.
Change-Id: I63e60d17ae16a020ce4d6de44baf3d152ea42a1a
|
|
When I wrote support for rnglists and loclists in the testsuite's DWARF
assembler, I made it with nested procs, for example proc "table" inside
proc "rnglists". The intention was that this proc "table" could only be
used by the user while inside proc "rnglists"'s body. I had chosen very
simple names, thinking there was no chance of name clashes. I recently
learned that this is not how TCL works. This ends up defining a proc
"table" in the current namespace ("Dwarf" in this case).
Things still work if you generate rnglists and loclists in the same
file, as each redefines its own procedures when executing. But if a
user of the assembler happened to define a convenience "table" or
"start_end" procedure, for example, it would get overriden.
I'd like to change how this works to reduce the chances of a name clash.
- Move the procs out of each other, so they are not defined in a nested
fashion.
- Prefix them with "_rnglists_" or "_loclists_".
- While calling $body in the various procs, temporarily make the procs
available under their "short" name. For example, while in rngllists'
body, make _rnglists_table available as just "table". This allows
existing code to keep working and keeps it not too verbose.
- Modify with_override to allow the overriden proc to not exist. In
that case, the temporary proc is deleted on exit.
Note the non-conforming indentation when calling with_override in
_loclists_list. This is on purpose: as we implement more loclists (and
rnglists) entry types, the indentation would otherwise get larger and
larger without much value for readability. So I think it's reasonable
here to put them on the same level.
Change-Id: I7bb48d26fcb0dba1ae4dada05c0c837212424328
|
|
A typical dwarf assembly test-case start like this:
...
standard_testfile .c -debug.S
set asm_file [standard_output_file $srcfile2]
Dwarf::assemble $asm_file {
...
}
if { [prepare_for_testing "failed to prepare" ${testfile} \
[list $srcfile $asm_file] {nodebug}] } {
return -1
}
...
When accidentally using build_for_executable instead of
prepare_for_testing (or intentionally using it but forgetting to add
clean_restart $binfile or some such) the mistake may not be caught, because
another gdb instance is still running, and we may silently end up testing
compiler-generated DWARF.
This can be caused by something relatively obvious, like an earlier
prepare_for_testing or clean_restart, but also by something more obscure like
function_range, which may even be triggered by dwarf assembly like this:
...
{MACRO_AT_func {main}}
...
Fix this by calling gdb_exit at the end of function_range.
Also fix the fallout of that in test-case gdb.dwarf2/dw2-bad-elf.exp, where a
get_sizeof call used the gdb instance left lingering by function_range.
[ A better and more complete fix would add a new proc get_exec_info, that would
be called at the start of the dwarf assembly body:
...
Dwarf::assemble $asm_file {
get_exec_info {main foo} {int void*}
...
that would:
- do a prepare_for_testing with $srcfile (roughtly equivalent to what
MACRO_AT_func does,
- call function_range for all functions main and foo, without starting a
new gdb instance
- set corresponding variables at the call-site: main_start, main_len,
main_end, foo_start, foo_len, foo_end.
- get size for types int and void*
- set corresponding variables at the call-site: int_size, void_ptr_size.
- do a gdb_exit. ]
Tested on x86_64-linux.
|
|
It is currently not possible to use variables in locations lists. For
example, with:
diff --git a/gdb/testsuite/gdb.dwarf2/loclists-multiple-cus.exp b/gdb/testsuite/gdb.dwarf2/loclists-multiple-cus.exp
index 6b4f5c8cbb8..cdbf948619f 100644
--- a/gdb/testsuite/gdb.dwarf2/loclists-multiple-cus.exp
+++ b/gdb/testsuite/gdb.dwarf2/loclists-multiple-cus.exp
@@ -30,6 +30,8 @@ if {![dwarf2_support]} {
return 0
}
+set myconst 0x123456
+
# Test with 32-bit and 64-bit DWARF.
foreach_with_prefix is_64 {false true} {
if { $is_64 } {
@@ -49,6 +51,7 @@ foreach_with_prefix is_64 {false true} {
global func1_addr func1_len
global func2_addr func2_len
global is_64
+ global myconst
# The CU uses the DW_FORM_loclistx form to refer to the .debug_loclists
# section.
@@ -107,7 +110,7 @@ foreach_with_prefix is_64 {false true} {
list_ {
# When in func1.
start_length $func1_addr $func1_len {
- DW_OP_constu 0x123456
+ DW_OP_constu $myconst
DW_OP_stack_value
}
we get:
$ make check TESTS="*/loclists-multiple-cus.exp"
...
gdb compile failed, build/gdb/testsuite/outputs/gdb.dwarf2/loclists-multiple-cus/loclists-multiple-cus-dw32.S: Assembler messages:
build/gdb/testsuite/outputs/gdb.dwarf2/loclists-multiple-cus/loclists-multiple-cus-dw32.S:78: Error: leb128 operand is an undefined symbol: $myconst
...
That means $myconst was copied literally to the generated assembly
file.
This patch fixes it, by running subst on the location list body, in
the context of the caller. The fix is applied to both
Dwarf::loclists::table::list_::start_length and
Dwarf::loclists::table::list_::start_end.
Reported-by: Zoran Zaric <Zoran.Zaric@amd.com>
Change-Id: I615a64431857242d9f477d5699e3732df1b31322
|
|
The current syntax of proc arange is:
...
proc arange { arange_start arange_length {comment ""} {seg_sel ""} } {
...
and a typical call looks like:
...
arange $start $len
...
This style is somewhat annoying because if you want to specify the last
parameter, you need to give the default values of all the other optional ones
before as well:
...
arange $start $len "" $seg_sel
...
Update the syntax to:
...
proc arange { options arange_start arange_length } {
parse_options {
{ comment "" }
{ seg_sel "" }
}
...
such that a typical call looks like:
...
arange {} $start $len
...
and a call using seg_sel looks like:
...
arange {
seg_sel $seg_sel
} $start $len
...
Also update proc aranges, which already has an options argument, to use the
new proc parse_options.
Tested on x86_64-linux.
Co-Authored-By: Simon Marchi <simon.marchi@polymtl.ca>
|
|
A best practise for DWARF [1] is to generate .debug_aranges entries for CUs
even if they have no address range.
Generate .debug_arange entries for the dummy CUs added by the DWARF assembler.
Tested on x86_64-linux.
[1] http://wiki.dwarfstd.org/index.php?title=Best_Practices
|
|
Add a proc aranges such that we can generate .debug_aranges sections in dwarf
assembly using:
...
cu { label cu_label } {
...
}
aranges {} cu_label {
arange $addr $len [<comment>] [$segment_selector]
}
...
Tested on x86_64-linux.
|
|
We can use current dwarf assembly infrastructure to declare a label that marks
the start of the CU header:
...
declare_labels header_start_cu_a
_section ".debug_info"
header_start_cu_a : cu {} {
}
_section ".debug_info"
header_start_cu_b : cu {} {
}
...
on the condition that we switch to the .debug_info section before, which makes
this style of use fragile.
Another way to achieve the same is to use the label as generated by the cu
proc itself:
...
variable _cu_label
cu {} {
}
set header_start_cu_a $_cu_label
cu {} {
}
set header_start_cu_b $_cu_label
...
but again that seems fragile given that adding a new CU inbetween will
silently result in the wrong value for the label.
Add a label option to proc cu such that we can simply do:
...
cu { label header_start_cu_a } {
}
cu { label header_start_cu_b } {
}
...
Tested on x86_64-linux.
|
|
Say one compiles a hello.c:
...
$ gcc -g hello.c
...
On openSUSE Leap 15.2 and Tumbleweed, the CU for hello.c is typically not the
first in .debug_info, nor the last, due to presence of debug information in
objects for sources like:
- ../sysdeps/x86_64/start.S
- init.c
- ../sysdeps/x86_64/crti.S
- elf-init.c
- ../sysdeps/x86_64/crtn.S.
On other systems, say ubuntu 18.04.5, the CU for hello.c is typically the
first and the last in .debug_info.
This difference has caused me to find some errors in the dwarf assembly
using openSUSE, that didn't show up on other platforms.
Force the same situation on other platforms by adding a dummy start
and end CU.
Tested on x86_64-linux.
gdb/testsuite/ChangeLog:
2021-08-22 Tom de Vries <tdevries@suse.de>
PR testsuite/28235
* lib/dwarf.exp (Dwarf::dummy_cu): New proc.
(Dwarf::assemble): Add dummy start and end CU.
|
|
This patch addresses a design problem with the symbol_needs_eval_context
class. It exposes the problem by introducing two new testsuite test
cases.
To explain the issue, I first need to explain the dwarf_expr_context
class that the symbol_needs_eval_context class derives from.
The intention behind the dwarf_expr_context class is to commonize the
DWARF expression evaluation mechanism for different evaluation
contexts. Currently in gdb, the evaluation context can contain some or
all of the following information: architecture, object file, frame and
compilation unit.
Depending on the information needed to evaluate a given expression,
there are currently three distinct DWARF expression evaluators:
- Frame: designed to evaluate an expression in the context of a call
frame information (dwarf_expr_executor class). This evaluator doesn't
need a compilation unit information.
- Location description: designed to evaluate an expression in the
context of a source level information (dwarf_evaluate_loc_desc
class). This evaluator expects all information needed for the
evaluation of the given expression to be present.
- Symbol needs: designed to answer a question about the parts of the
context information required to evaluate a DWARF expression behind a
given symbol (symbol_needs_eval_context class). This evaluator
doesn't need a frame information.
The functional difference between the symbol needs evaluator and the
others is that this evaluator is not meant to interact with the actual
target. Instead, it is supposed to check which parts of the context
information are needed for the given DWARF expression to be evaluated by
the location description evaluator.
The idea is to take advantage of the existing dwarf_expr_context
evaluation mechanism and to fake all required interactions with the
actual target, by returning back dummy values. The evaluation result is
returned as one of three possible values, based on operations found in a
given expression:
- SYMBOL_NEEDS_NONE,
- SYMBOL_NEEDS_REGISTERS and
- SYMBOL_NEEDS_FRAME.
The problem here is that faking results of target interactions can yield
an incorrect evaluation result.
For example, if we have a conditional DWARF expression, where the
condition depends on a value read from an actual target, and the true
branch of the condition requires a frame information to be evaluated,
while the false branch doesn't, fake target reads could conclude that a
frame information is not needed, where in fact it is. This wrong
information would then cause the expression to be actually evaluated (by
the location description evaluator) with a missing frame information.
This would then crash the debugger.
The gdb.dwarf2/symbol_needs_eval_fail.exp test introduces this
scenario, with the following DWARF expression:
DW_OP_addr $some_variable
DW_OP_deref
# conditional jump to DW_OP_bregx
DW_OP_bra 4
DW_OP_lit0
# jump to DW_OP_stack_value
DW_OP_skip 3
DW_OP_bregx $dwarf_regnum 0
DW_OP_stack_value
This expression describes a case where some variable dictates the
location of another variable. Depending on a value of some_variable, the
variable whose location is described by this expression is either read
from a register or it is defined as a constant value 0. In both cases,
the value will be returned as an implicit location description on the
DWARF stack.
Currently, when the symbol needs evaluator fakes a memory read from the
address behind the some_variable variable, the constant value 0 is used
as the value of the variable A, and the check returns the
SYMBOL_NEEDS_NONE result.
This is clearly a wrong result and it causes the debugger to crash.
The scenario might sound strange to some people, but it comes from a
SIMD/SIMT architecture where $some_variable is an execution mask. In
any case, it is a valid DWARF expression, and GDB shouldn't crash while
evaluating it. Also, a similar example could be made based on a
condition of the frame base value, where if that value is concluded to
be 0, the variable location could be defaulted to a TLS based memory
address.
The gdb.dwarf2/symbol_needs_eval_timeout.exp test introduces a second
scenario. This scenario is a bit more abstract due to the DWARF
assembler lacking the CFI support, but it exposes a different
manifestation of the same problem. Like in the previous scenario, the
DWARF expression used in the test is valid:
DW_OP_lit1
DW_OP_addr $some_variable
DW_OP_deref
# jump to DW_OP_fbreg
DW_OP_skip 4
DW_OP_drop
DW_OP_fbreg 0
DW_OP_dup
DW_OP_lit0
DW_OP_eq
# conditional jump to DW_OP_drop
DW_OP_bra -9
DW_OP_stack_value
Similarly to the previous scenario, the location of a variable A is an
implicit location description with a constant value that depends on a
value held by a global variable. The difference from the previous case
is that DWARF expression contains a loop instead of just one branch. The
end condition of that loop depends on the expectation that a frame base
value is never zero. Currently, the act of faking the target reads will
cause the symbol needs evaluator to get stuck in an infinite loop.
Somebody could argue that we could change the fake reads to return
something else, but that would only hide the real problem.
The general impression seems to be that the desired design is to have
one class that deals with parsing of the DWARF expression, while there
are virtual methods that deal with specifics of some operations.
Using an evaluator mechanism here doesn't seem to be correct, because
the act of evaluation relies on accessing the data from the actual
target with the possibility of skipping the evaluation of some parts of
the expression.
To better explain the proposed solution for the issue, I first need to
explain a couple more details behind the current design:
There are multiple places in gdb that handle DWARF expression parsing
for different purposes. Some are in charge of converting the expression
to some other internal representation (decode_location_expression,
disassemble_dwarf_expression and dwarf2_compile_expr_to_ax), some are
analysing the expression for specific information
(compute_stack_depth_worker) and some are in charge of evaluating the
expression in a given context (dwarf_expr_context::execute_stack_op
and decode_locdesc).
The problem is that all those functions have a similar (large) switch
statement that handles each DWARF expression operation. The result of
this is a code duplication and harder maintenance.
As a step into the right direction to solve this problem (at least for
the purpose of a DWARF expression evaluation) the expression parsing was
commonized inside of an evaluator base class (dwarf_expr_context). This
makes sense for all derived classes, except for the symbol needs
evaluator (symbol_needs_eval_context) class.
As described previously the problem with this evaluator is that if the
evaluator is not allowed to access the actual target, it is not really
evaluating.
Instead, the desired function of a symbol needs evaluator seems to fall
more into expression analysis category. This means that a more natural
fit for this evaluator is to be a symbol needs analysis, similar to the
existing compute_stack_depth_worker analysis.
Another problem is that using a heavyweight mechanism of an evaluator
to do an expression analysis seems to be an unneeded overhead. It also
requires a more complicated design of the parent class to support fake
target reads.
The reality is that the whole symbol_needs_eval_context class can be
replaced with a lightweight recursive analysis function, that will give
more correct result without compromising the design of the
dwarf_expr_context class. The analysis treats the expression byte
stream as a DWARF operation graph, where each graph node can be
visited only once and each operation can decide if the frame context
is needed for their evaluation.
The downside of this approach is adding of one more similar switch
statement, but at least this way the new symbol needs analysis will be
a lightweight mechnism and it will provide a correct result for any
given DWARF expression.
A more desired long term design would be to have one class that deals
with parsing of the DWARF expression, while there would be a virtual
methods that deal with specifics of some DWARF operations. Then that
class would be used as a base for all DWARF expression parsing mentioned
at the beginning.
This however, requires a far bigger changes that are out of the scope
of this patch series.
The new analysis requires the DWARF location description for the
argc argument of the main function to change in the assembly file
gdb.python/amd64-py-framefilter-invalidarg.S. Originally, expression
ended with a 0 value byte, which was never reached by the symbol needs
evaluator, because it was detecting a stack underflow when evaluating
the operation before. The new approach does not simulate a DWARF
stack anymore, so the 0 value byte needs to be removed because it
makes the DWARF expression invalid.
gdb/ChangeLog:
* dwarf2/loc.c (class symbol_needs_eval_context): Remove.
(dwarf2_get_symbol_read_needs): New function.
(dwarf2_loc_desc_get_symbol_read_needs): Remove.
(locexpr_get_symbol_read_needs): Use
dwarf2_get_symbol_read_needs.
gdb/testsuite/ChangeLog:
* gdb.python/amd64-py-framefilter-invalidarg.S : Update argc
DWARF location expression.
* lib/dwarf.exp (_location): Handle DW_OP_fbreg.
* gdb.dwarf2/symbol_needs_eval.c: New file.
* gdb.dwarf2/symbol_needs_eval_fail.exp: New file.
* gdb.dwarf2/symbol_needs_eval_timeout.exp: New file.
|
|
Without that it is impossible to debug on riscv64.
gdb/
PR symtab/27999
* dwarf2/loc.c (decode_debug_loclists_addresses): Support
DW_LLE_start_end.
gdb/testsuite/
PR symtab/27999
* lib/dwarf.exp (start_end): New proc inside loclists.
* gdb.dwarf2/loclists-start-end.exp: New file.
* gdb.dwarf2/loclists-start-end.c: New file.
|
|
gdb/testsuite/ChangeLog:
2021-04-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* lib/dwarf.exp (_location): Recognize DW_OP_fbreg as an op.
|
|
This commit fixes fission support in the Dwarf assembler. I added the
new test gdb.dwarf2/fission-absolute-dwo.exp which is a simple example
of using the fission support. I also rewrote the existing test
gdb.dwarf2/fission-multi-cu.exp to use the new functionality (instead
of using an x86-64 only assembler file).
To better support compiling the assembler files produced by the Dwarf
assembler I have added the new proc build_executable_and_dwo_files in
lib/dwarf.exp, this replaces build_executable_from_fission_assembler,
all the tests that used the old proc have been updated. Where the old
proc assumed a single .S source file which contained the entire test,
the new proc allows for multiple source files.
The Dwarf assembler already had some fission support, however, this
was not actually used in any tests, and when I tried using it there
were a few issues.
The biggest change is that we now generate DW_FORM_GNU_addr_index
instead of DW_FORM_addr for the low and high pc in
_handle_macro_at_range, support for the DW_FORM_GNU_addr_index is new
in this commit.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/fission-absolute-dwo.c: New file.
* gdb.dwarf2/fission-absolute-dwo.exp: New file.
* gdb.dwarf2/fission-base.exp: Use build_executable_and_dwo_files
instead of build_executable_from_fission_assembler.
* gdb.dwarf2/fission-loclists-pie.exp: Likewise.
* gdb.dwarf2/fission-loclists.exp: Likewise.
|
|
I had written a DWARF location expression like
DW_OP_const1u
DW_OP_stack_value
... and was surprised to see that the DW_OP_stack_value didn't appear
in the "readelf" output.
The problem here is that DW_OP_const1u requires an operand, but
neither the DWARF assembler nor gas diagnosed this problem.
This patch adds some checking to Dwarf::_location to try to avoid this
in the future. The checking is done via a helper proc that also
dissects the argument list and sets an array in the caller's frame.
gdb/testsuite/ChangeLog
2021-03-31 Tom Tromey <tromey@adacore.com>
* lib/dwarf.exp (Dwarf::_get_args): New proc.
(Dwarf::_location): Use it.
|
|
When handling DWARF attributes of the form DW_FORM_strp the strings
should be placed in the .debug_str section, not .debug_string as they
currently are by the DWARF assembler (in lib/dwarf.exp).
I've added a test. This is as much to test the DWARF generator as it
is to test GDB as GCC makes frequent use of DW_FORM_strp so we can be
pretty sure this part of GDB is already well tested.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/dw2-using-debug-str.c: New file.
* gdb.dwarf2/dw2-using-debug-str.exp: New file.
* lib/dwarf.exp (Dwarf::DW_FORM_strp): Create .debug_str section,
not .debug_string.
|
|
If DWARF contains a reference to a "dwz" file, but there is no
.gnu_debugaltlink section, then gdb will crash. This happens because
dwarf2_get_dwz_file will return NULL, but some callers do not expect
this.
This patch changes dwarf2_get_dwz_file so that callers can require a
dwz file. Then, it updates the callers that are attempting to process
references to the dwz file to require one.
This includes a new testcase. The dwarf.exp changes don't handle the
new forms exactly correctly -- they are only handled well enough to
let this test case complete.
gdb/ChangeLog
2021-03-06 Tom Tromey <tom@tromey.com>
* dwarf2/read.h (dwarf2_get_dwz_file): Add 'require' parameter.
* dwarf2/read.c (dwarf2_get_dwz_file): Add 'require' parameter.
(get_abbrev_section_for_cu, read_attribute_value)
(get_debug_line_section): Update.
* dwarf2/macro.c (dwarf_decode_macro_bytes): Update.
gdb/testsuite/ChangeLog
2021-03-06 Tom Tromey <tom@tromey.com>
* lib/dwarf.exp (_handle_DW_FORM): Treat DW_FORM_GNU_ref_alt and
DW_FORM_GNU_strp_alt like DW_FORM_sec_offset.
* gdb.dwarf2/dwznolink.exp: New file.
|
|
Since it has gone from bfd/.
* arm-symbian-tdep.c: Delete.
* NEWS: Mention arm-symbian removal.
* Makefile.in: Remove arm-symbian-tdep entries.
* configure.tgt: Remove arm*-*-symbianelf*.
* doc/gdb.texinfo: Remove mention of SymbianOS.
* osabi.c (gdb_osabi_names): Remove "Symbian".
* osabi.h (enum gdb_osabi): Remove GDB_OSABI_SYMBIAN.
* testsuite/gdb.base/ending-run.exp: Remove E32Main handling.
* testsuite/gdb.ada/catch_ex_std.exp: Remove arm*-*-symbianelf*
handling.
* testsuite/gdb.base/dup-sect.exp: Likewise.
* testsuite/gdb.base/long_long.exp: Likewise.
* testsuite/gdb.base/solib-weak.exp: Likewise.
* testsuite/gdb.guile/scm-section-script.exp: Likewise.
* testsuite/gdb.python/py-section-script.exp: Likewise.
* testsuite/lib/dwarf.exp: Likewise.
* testsuite/lib/gdb.exp: Likewise.
|
|
It is possible for the tables in the .debug_{rng,loc}lists sections to
not have an array of offsets. In that case, the offset_entry_count
field of the header is 0. The forms DW_FORM_{rng,loc}listx (reference
by index) can't be used with that table. Instead, the
DW_FORM_sec_offset form, which references a {rng,loc}list by direct
offset in the section, must be used. From what I saw, this is what GCC
currently produces.
Add tests for this case. I didn't see any bug related to this, I just
think that it would be nice to have coverage for this. A new
`-with-offset-array` option is added to the `table` procs, used when
generating {rng,loc}lists, to decide whether to generate the offset
array.
gdb/testsuite/ChangeLog:
* lib/dwarf.exp (rnglists): Add -no-offset-array option to
table proc.
* gdb.dwarf2/rnglists-sec-offset.exp: Add test for
.debug_rnglists table without offset array.
* gdb.dwarf2/loclists-sec-offset.exp: Add test for
.debug_loclists table without offset array.
Change-Id: I8e34a7bf68c9682215ffbbf66600da5b7db91ef7
|
|
Add tests for the various issues fixed in the previous patches.
Add a new "loclists" procedure to the DWARF assembler, to allow
generating .debug_loclists sections.
gdb/testsuite/ChangeLog:
PR gdb/26813
* lib/dwarf.exp (_handle_DW_FORM): Handle DW_FORM_loclistx.
(loclists): New proc.
* gdb.dwarf2/loclists-multiple-cus.c: New.
* gdb.dwarf2/loclists-multiple-cus.exp: New.
* gdb.dwarf2/loclists-sec-offset.c: New.
* gdb.dwarf2/loclists-sec-offset.exp: New.
Change-Id: I209bcb2a9482762ae943e518998d1f7761f76928
|
|
The _location proc is used to assemble a location description. It needs
to know some contextual information:
- size of an address
- size of an offset (into another DWARF section)
- DWARF version
It currently get all this directly from global variables holding the
compilation unit information. This is fine because as of now, all
location descriptions are generated in the context of creating a
compilation unit. However, a subsequent patch will generate location
descriptions while generating a .debug_loclists section. _location
should therefore no longer rely on the current compilation unit's
properties.
Change it to accept these values as parameters instead of accessing the
values for the CU.
No functional changes intended.
gdb/testsuite/ChangeLog:
* lib/dwarf.exp (_location): Add parameters.
(_handle_DW_FORM): Adjust.
Change-Id: Ib94981979c83ffbebac838081d645ad71c221637
|
