With test-case gdb.cp/temargs.exp on target board \
unix/gdb:debug_flags=-gdwarf-5 I run into:
...
(gdb) info addr I^M
ERROR: GDB process no longer exists
GDB process exited with wait status 32286 exp19 0 0 CHILDKILLED SIGABRT SIGABRT
UNRESOLVED: gdb.cp/temargs.exp: test address of I in templ_m
...
This is a regression since commit 529908cbd0 "Remove DW_UNSND".
The problem is that this DW_AT_decl_file:
...
<1><221>: Abbrev Number: 4 (DW_TAG_structure_type)
<222> DW_AT_name : Base<double, 23, (& a_global), &S::f>
<226> DW_AT_byte_size : 1
<226> DW_AT_decl_file : 1
<226> DW_AT_decl_line : 30
<227> DW_AT_sibling : <0x299>
...
is not read by this code in new_symbol:
....
attr = dwarf2_attr (die,
inlined_func ? DW_AT_call_file : DW_AT_decl_file,
cu);
if (attr != nullptr && attr->form_is_unsigned ())
...
because DW_AT_decl_file has form DW_FORM_implicit_const:
...
4 DW_TAG_structure_type [has children]
DW_AT_name DW_FORM_strp
DW_AT_byte_size DW_FORM_implicit_const: 1
DW_AT_decl_file DW_FORM_implicit_const: 1
DW_AT_decl_line DW_FORM_data1
DW_AT_sibling DW_FORM_ref4
DW_AT value: 0 DW_FORM value: 0
...
which is a signed LEB128, so attr->form_is_unsigned () returns false.
Fix this by introducing new functions is_nonnegative and as_nonnegative, and
use these instead of form_is_unsigned and as_unsigned.
Tested on x86_64-linux.
gdb/ChangeLog:
2021-02-24 Tom de Vries <tdevries@suse.de>
PR symtab/27336
* dwarf2/attribute.c (attribute::form_is_signed): New function
factored out of ...
* dwarf2/attribute.h (attribute::as_signed): ... here.
(attribute::is_nonnegative, attribute::as_nonnegative): New function.
(attribute::form_is_signed): Declare.
* dwarf2/read.c (new_symbol): Use is_nonnegative and as_nonnegative
for DW_AT_decl_file.
We hit an assertion when loading the binary from PR 26813. When fixing
it, execution goes a up bit further but then hits another assert, and
another, and another. With these fours fixes, I am able to load the
binary and get to the prompt. An error is shown (index pointing outside
of the section), because the DW_FORM_rnglistx attribute is not read
correctly, but that one is taken care of by the next patch.
The four fixes are:
- attribute::form_requires_reprocessing needs to handle forms
DW_FORM_rnglistx and DW_FORM_loclistx, because set_unsigned_reprocess
is called for them in read_attribute_value.
- read_attribute_reprocess must call set_unsigned for them, not
set_address. The parameter of set_address is a CORE_ADDR, meaning
it's for program addresses. Post-reprocess, DW_FORM_rnglistx and
DW_FORM_loclistx are offsets into their respective sections
(.debug_rnglists and .debug_loclists). set_unsigned is the current
attribute value setter that fits the best. But perhaps we should have
a setter that takes a sect_offset?
- read_attribute_process must call as_unsigned_reprocess instead of
as_unsigned to get the pre-reprocess value, otherwise we hit the
assert inside as_unsigned that makes sure the attribute doesn't need
reprocessing.
- attribute::set_unsigned needs to clear the requires_reprocessing flag,
otherwise it stays set when reprocessing DW_FORM_rnglistx and
DW_FORM_loclistx attributes.
There's another assert that we hit once the next patch is applied, but
since it's in the same vein as the changes in this patch, I included it
in this patch:
- attribute::form_is_unsigned must handle form DW_FORM_loclistx,
otherwise we hit the assert when trying to call set_unsigned for an
attribute of this form. DW_FORM_rnglistx is already handled.
gdb/ChangeLog:
PR gdb/26813
* dwarf2/attribute.h (struct attribute) <set_unsigned>: Clear
requires_reprocessing flag.
* dwarf2/attribute.c (attribute::form_is_unsigned): Handle
DW_FORM_loclistx.
(attribute::form_requires_reprocessing): Handle DW_FORM_rnglistx
and DW_FORM_loclistx.
* dwarf2/read.c (read_attribute_reprocess): Use set_unsigned
instead of set_address for DW_FORM_loclistx and
DW_FORM_rnglistx.
Change-Id: I06c156fa3913ca98e4e39085f4ef171645b4bc1e
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.
This removes DW_UNSND, replacing uses with either as_unsigned or
constant_value, depending primarily on whether or not the form is
already known to be appropriate.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (lookup_dwo_id, get_type_unit_group)
(read_file_scope, dwarf2_get_pc_bounds)
(dwarf2_record_block_ranges, dwarf2_add_field, get_alignment)
(read_structure_type, handle_struct_member_die)
(read_enumeration_type, read_array_type, read_set_type)
(read_tag_pointer_type, read_tag_reference_type)
(read_subroutine_type, read_base_type, read_subrange_type)
(read_full_die_1, partial_die_info::read)
(partial_die_info::read, by, new_symbol)
(dwarf2_const_value_data, dwarf2_const_value_attr)
(dump_die_shallow, dwarf2_fetch_constant_bytes)
(prepare_one_comp_unit): Update.
* dwarf2/attribute.h (DW_UNSND): Remove.
This adds a new attribute::as_boolean method, and updates the reader
to use it. The main benefit of this change is that now the code will
respect the attribute's form.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_func_scope, prototyped_function_p)
(read_subroutine_type, partial_die_info::read)
(dwarf2_flag_true_p, new_symbol, dump_die_shallow)
(dwarf2_add_member_fn): Update.
* dwarf2/attribute.h (struct attribute) <as_boolean>: Declare.
* dwarf2/attribute.c (attribute::as_boolean): New method.
This adds a new attribute::as_virtuality method and changes the DWARF
reader to use it. This also ensures that the attibute's form will now
be respected.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (dwarf2_add_field, dwarf2_add_member_fn): Update.
* dwarf2/attribute.h (struct attribute) <as_virtuality>: New
method.
* dwarf2/attribute.c (attribute::as_virtuality): New method.
This changes is_valid_DW_AT_defaulted to be a method on struct attribute.
Now it correctly respects the form of the attribute.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (is_valid_DW_AT_defaulted): Move to attribute.c.
(dwarf2_add_member_fn): Update.
* dwarf2/attribute.h (struct attribute) <defaulted>: Declare.
* dwarf2/attribute.c (attribute::defaulted): New method, from
is_valid_DW_AT_defaulted.
This introduces a new attribute::as_unsigned method and changes a few
spots to use it.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (dw2_get_file_names_reader)
(dwarf2_build_include_psymtabs, handle_DW_AT_stmt_list)
(dwarf2_cu::setup_type_unit_groups, fill_in_loclist_baton)
(dwarf2_symbol_mark_computed): Use as_unsigned.
* dwarf2/attribute.h (struct attribute) <as_unsigned>: New
method.
<form_is_section_offset>: Update comment.
Currently gdb keeps a vector of attributes that require reprocessing.
However, now that there is a reprocessing flag in the attribute, we
can remove the vector and instead simply loop over attributes a second
time. Normally there are not many attributes, so this should be
reasonably cheap.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (skip_one_die): Update.
(read_full_die_1): Change how reprocessing is done.
(partial_die_info::read): Update.
(read_attribute_value): Remove need_reprocess parameter.
(read_attribute): Likewise.
* dwarf2/attribute.h (struct attribute) <requires_reprocessing_p>:
New method.
Some forms require "reprocessing" -- a second pass to update their
value appropriately. In this case, we'll set the unsigned value on
the attribute, and then later set it to the correct value.
To handle this, we introduce a reprocessing flag to attribute. Then,
we manage this flag to ensure that setting and unsetting is done
properly.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_cutu_die_from_dwo): Use OBSTACK_ZALLOC.
(read_attribute_reprocess, read_attribute_value): Update.
(read_attribute): Clear requires_reprocessing.
* dwarf2/attribute.h (struct attribute) <as_unsigned_reprocess,
form_requires_reprocessing>: New methods.
<string_init>: Clear requires_reprocessing.
<set_unsigned_reprocess>: New method.
<name>: Shrink by one bit.
<requires_reprocessing>: New member.
* dwarf2/attribute.c (attribute::form_requires_reprocessing): New
method.
This adds form_is_unsigned and an unsigned setter method to struct
attribute, and updates the remaining code. Now DW_UNSND is no longer
used as an lvalue.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_attribute_value): Update.
* dwarf2/attribute.h (struct attribute) <form_is_unsigned,
set_unsigned>: New methods.
* dwarf2/attribute.c (attribute::form_is_unsigned): New method.
This removes DW_SND in favor of accessors on struct attribute.
These accessors check that the form is appropriate.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (get_alignment, read_array_order)
(read_attribute_value, dwarf2_const_value_attr)
(dump_die_shallow, dwarf2_fetch_constant_bytes): Update.
* dwarf2/attribute.h (struct attribute) <as_signed, set_signed>:
New methods.
(DW_SND): Remove.
This removes DW_SIGNATURE in favor of methods on struct attribute. As
usual, the methods check the form, which DW_SIGNATURE did not do.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_attribute_value, lookup_die_type)
(dump_die_shallow, follow_die_sig, get_DW_AT_signature_type):
Update.
* dwarf2/attribute.h (struct attribute) <as_signature,
set_signature>: New methods.
(DW_SIGNATURE): Remove.
This removes the DW_BLOCK accessor in favor of methods on struct
attribute. The methods, unlike the access, check the form.
Note that DW_FORM_data16 had to be handled by form_is_block, because
in practice that is how we store values of this form.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_call_site_scope)
(handle_data_member_location, dwarf2_add_member_fn)
(mark_common_block_symbol_computed, attr_to_dynamic_prop)
(partial_die_info::read, read_attribute_value)
(var_decode_location, dwarf2_const_value_attr, dump_die_shallow)
(dwarf2_fetch_die_loc_sect_off, dwarf2_fetch_constant_bytes)
(dwarf2_symbol_mark_computed): Update.
* dwarf2/attribute.h (struct attribute) <as_block, set_block>: New
methods.
(DW_BLOCK): Remove.
* dwarf2/attribute.c (attribute::form_is_block): Add
DW_FORM_data16.
This removes DW_STRING and DW_STRING_IS_CANONICAL, replacing them with
accessor methods on struct attribute. The new code ensures that a
string value will only ever be used when the form allows it.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_cutu_die_from_dwo)
(read_attribute_reprocess, read_attribute_value, read_attribute)
(dwarf2_const_value_attr, dwarf2_name, dump_die_shallow)
(dwarf2_fetch_constant_bytes): Update.
* dwarf2/attribute.h (struct attribute) <form_is_string>: Declare.
<set_string_noncanonical, set_string_canonical>: New methods.
<string_is_canonical>: Update comment.
<canonical_string_p>: Add assert.
(DW_STRING, DW_STRING_IS_CANONICAL): Remove.
* dwarf2/attribute.c (attribute::form_is_string): New method.
(attribute::string): Use it.
This removes the rvalue uses of DW_STRING_IS_CANONICAL, replacing them
with an accessor method.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (anonymous_struct_prefix, dwarf2_name)
(dump_die_shallow): Use canonical_string_p.
* dwarf2/attribute.h (struct attribute) <canonical_string_p>: New
method.
This removes the "value_" prefix from the struct value accessors.
This seemed unnecessarily wordy to me.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (dwarf2_find_base_address, read_call_site_scope)
(dwarf2_get_pc_bounds, dwarf2_record_block_ranges)
(partial_die_info::read, dwarf2_string_attr, new_symbol): Update.
* dwarf2/attribute.h (struct attribute): Rename methods.
* dwarf2/attribute.c (attribute::as_address): Rename from
value_as_address.
(attribute::as_string): Rename from value_as_string.
This inlines a couple of methods on struct attribute, improving the
performance of DWARF partial symbol reading. These methods were
discovered as hot spots using callgrind.
For this patch, and for all the patches in this series, I tested gdb's
performance on three programs:
1. gdb itself -- I built gdb and copied it to /tmp, ensuring that the
same version was used in all tests.
2. The system libxul.so, the main library of Firefox. I installed the
separate debuginfo and ensured that gdb read it.
3. A large-ish Ada program that I happen to have.
I ran gdb 10 times like:
/bin/time -f %e \
./gdb/gdb --data-directory ./gdb/data-directory -nx \
-iex 'set debug-file-directory /usr/lib/debug' \
-batch $X
... where $X was the test executable. Then I computed the mean time.
This was all done with a standard (-g -O2) build of gdb.
The baseline times were
gdb 1.90
libxul 2.12
Ada 2.61
This patch brings the numbers down to
gdb 1.88
libxul 2.11
Ada 2.60
Not a huge change, but still visible in the results.
gdb/ChangeLog
2020-05-27 Tom Tromey <tromey@adacore.com>
* dwarf2/attribute.h (struct attribute) <form_is_ref>: Inline.
<get_ref_die_offset>: Inline.
<get_ref_die_offset_complaint>: New method.
* dwarf2/attribute.c (attribute::form_is_ref): Move to header.
(attribute::get_ref_die_offset_complaint): Rename from
get_ref_die_offset. Just issue complaint.
The full DIE reader checks that an attribute has a "string" form in
some spots, but the partial DIE reader does not. This patch brings
the two readers in sync for one specific case, namely when examining
the linkage name. This avoids regressions in an existing DWARF test
case.
A full fix for this problem would be preferable. An accessor like
DW_STRING should always check the form. However, I haven't attempted
that in this series.
Also the fact that the partial and full readers can disagree like this
is a design flaw.
gdb/ChangeLog
2020-04-24 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (partial_die_info::read) <case
DW_AT_linkage_name>: Use value_as_string.
(dwarf2_string_attr): Use value_as_string.
* dwarf2/attribute.h (struct attribute) <value_as_string>: Declare
method.
* dwarf2/attribute.c (attribute::value_as_string): New method.
I noticed that a comment in dwarf2/attribute.h still referred to
dwarf2_get_attr_constant_value. However, this is now a method on
struct attribute.
gdb/ChangeLog
2020-03-28 Tom Tromey <tom@tromey.com>
* dwarf2/attribute.h (struct attribute) <form_is_constant>: Update
comment.
This changes dwarf2_get_ref_die_offset and
dwarf2_get_attr_constant_value to be methods on struct attribute.
gdb/ChangeLog
2020-03-26 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (handle_data_member_location, dwarf2_add_field)
(mark_common_block_symbol_computed, read_tag_string_type)
(attr_to_dynamic_prop, read_subrange_type): Update.
(dwarf2_get_ref_die_offset, dwarf2_get_attr_constant_value): Move
to be methods on struct attribute.
(skip_one_die, process_imported_unit_die, read_namespace_alias)
(read_call_site_scope, partial_die_info::read)
(partial_die_info::read, lookup_die_type, follow_die_ref):
Update.
* dwarf2/attribute.c (attribute::get_ref_die_offset): New method,
from dwarf2_get_ref_die_offset.
(attribute::constant_value): New method, from
dwarf2_get_attr_constant_value.
* dwarf2/attribute.h (struct attribute) <get_ref_die_offset>:
Declare method.
<constant_value>: New method.
This changes attr_form_is_block to be a method. This is done
separately because, unlike the other attribute functions,
attr_form_is_block had special handling for the case where the
argument was NULL. This required auditing each call site; in most
cases, NULL was already ruled out, but in a few spots, an additional
check was needed.
gdb/ChangeLog
2020-02-08 Tom Tromey <tom@tromey.com>
* dwarf2read.c (read_call_site_scope)
(handle_data_member_location, dwarf2_add_member_fn)
(mark_common_block_symbol_computed, read_common_block)
(attr_to_dynamic_prop, partial_die_info::read)
(var_decode_location, dwarf2_fetch_die_loc_sect_off)
(dwarf2_symbol_mark_computed, set_die_type): Update.
* dwarf2/attribute.h (struct attribute) <form_is_block>: Declare
method.
(attr_form_is_block): Don't declare.
* dwarf2/attribute.c (attribute::form_is_block): Now a method.
Change-Id: Idfb290c61d738301ab991666f43e0b9cf577b2ae
This moves the attribute-related code out of dwarf2read.c and into the
new files dwarf2/attribute.[ch].
gdb/ChangeLog
2020-02-08 Tom Tromey <tom@tromey.com>
* dwarf2read.c (struct attribute, DW_STRING)
(DW_STRING_IS_CANONICAL, DW_UNSND, DW_BLOCK, DW_SND, DW_ADDR)
(DW_SIGNATURE, struct dwarf_block, attr_value_as_address)
(attr_form_is_block, attr_form_is_section_offset)
(attr_form_is_constant, attr_form_is_ref): Move.
* dwarf2/attribute.h: New file.
* dwarf2/attribute.c: New file, from dwarf2read.c.
* Makefile.in (COMMON_SFILES): Add dwarf2/attribute.c.
Change-Id: I1ea4c146256a1b9e38b66f1c605d782a14eeded7
