The code was assuming that the elf file will have a PT_LOAD segment
starting from the first byte of the file. While this is true for files
generated by most linkers (it's a way of saving space), it is not a
requirement. And files not satisfying this constraint can still be
perfectly executable. yaml2obj is one of the tools which produces files
like this.
This patch relaxes the check in ObjectFileELF to take the address of the
first PT_LOAD segment as the base address of the object (instead of the
one with the offset 0). Since the PT_LOAD segments are supposed to be
sorted according to the VM address, this entry will also be the one with
the lowest VM address.
If we ever run into files which don't have the PT_LOAD segments sorted,
we can easily change this code to return the lowest VM address as the
base address (if that is the correct thing to do for these files).
llvm-svn: 350923
Summary:
The concept of a base address was already present in the implementation
(it's needed for computing section load addresses properly), but it was
never exposed through this function. This fixes that.
llvm-svn: 350804
Summary:
This is the result of the discussion in D55356, where it was suggested
as a solution to representing the addresses that logically belong to a
module in memory, but are not a part of any of its sections.
The ELF PT_LOAD segments are similar to the MachO "load commands",
except that the relationship between them and the object file sections
is a bit weaker. While in the MachO case, the sections belonging to a
specific segment are placed directly inside it in the object file
logical structur, in the ELF case, the sections and segments form two
separate hierarchies. This means that it is in theory possible to create
an elf file where only a part of a section would belong to some segment
(and another part to a different one). However, I am not aware of any
tool which would produce such a file (and most tools will have problems
ingesting them), so this means it is still possible to follow the MachO
model and make sections children of the PT_LOAD segments.
In case we run into (corrupt?) files with overlapping sections, I have
added code (and tests) which adjusts the sizes and/or drops the offending
sections in order to present a reasonable image to the upper layers of
LLDB. This is mostly done for completeness, as I don't anticipate
running into this situation in the real world. However, if we do run
into it, and the current behavior is not suitable for some reason, we
can implement this logic differently.
Reviewers: clayborg, jankratochvil, krytarowski, joerg, espindola
Subscribers: emaste, arichardson, lldb-commits
Differential Revision: https://reviews.llvm.org/D55998
llvm-svn: 350742
Summary:
instead of returning the architecture through by-ref argument and a
boolean value indicating success, we can just return the ArchSpec
directly. Since the ArchSpec already has an invalid state, it can be
used to denote the failure without the additional bool.
Reviewers: clayborg, zturner, espindola
Subscribers: emaste, arichardson, JDevlieghere, lldb-commits
Differential Revision: https://reviews.llvm.org/D56129
llvm-svn: 350291
Summary:
The first section header does not define a real section. Instead it is
used for various elf extensions. This patch skips creation of a section
for index 0.
This has one furtunate side-effect, in that it allows us to use the section
header index as the Section ID (where 0 is also invalid). This way, we
can get rid of a lot of spurious +1s in the ObjectFileELF code.
Reviewers: clayborg, krytarowski, joerg, espindola
Subscribers: emaste, lldb-commits, arichardson
Differential Revision: https://reviews.llvm.org/D55757
llvm-svn: 349498
Summary:
This patch attempts to move as much code as possible out of the
CreateSections function to make room for future improvements there. Some
of this may be slightly over-engineered (VMAddressProvider), but I
wanted to keep the logic of this function very simple, because once I
start taking segment headers into acount (as discussed in D55356), the
function is going to grow significantly.
While in there, I also added tests for various bits of functionality.
This should be NFC, except that I changed the order of hac^H^Heuristicks
for determining section type slightly. Previously, name-based deduction
(.symtab -> symtab) would take precedence over type-based (SHT_SYMTAB ->
symtab) one. In fact we would assert if we ran into a .text section with
type SHT_SYMTAB. Though unlikely to matter in practice, this order
seemed wrong to me, so I have inverted it.
Reviewers: clayborg, krytarowski, espindola
Subscribers: emaste, arichardson, lldb-commits
Differential Revision: https://reviews.llvm.org/D55706
llvm-svn: 349268
This patch simplifies boolean expressions acorss LLDB. It was generated
using clang-tidy with the following command:
run-clang-tidy.py -checks='-*,readability-simplify-boolean-expr' -format -fix $PWD
Differential revision: https://reviews.llvm.org/D55584
llvm-svn: 349215
Move code into a separate function, and replace the if-else chain with
llvm::StringSwitch.
A slight behavioral change is that now I use the section flags
(SHF_TLS) instead of the section name to set the thread-specific
property. There is no explanation in the original commit introducing
this (r153537) as to why that was done this way, but the new behavior
should be more correct.
llvm-svn: 348936
Instead of GetProgramHeaderCount+GetProgramHeaderByIndex, expose an
ArrayRef of all program headers, to enable range-based iteration.
Instead of GetSegmentDataByIndex, expose GetSegmentData, taking a
program header (reference).
This makes the code simpler by enabling range-based loops and also
allowed to remove some null checks, as it became locally obvious that
some pointers can never be null.
llvm-svn: 348928
Test cases were updated to not use the local compilation dir which
is different between development pc and build bots.
Original commit message:
[LLDB] - Support the single file split DWARF.
DWARF5 spec describes a single file split dwarf case
(when .dwo sections are in the .o files).
Problem is that LLDB does not work correctly in that case.
The issue is that, for example, both .debug_info and .debug_info.dwo
has the same type: eSectionTypeDWARFDebugInfo. And when code searches
section by type it might find the regular debug section
and not the .dwo one.
The patch fixes that. With it, LLDB is able to work with
output compiled with -gsplit-dwarf=single flag correctly.
Differential revision: https://reviews.llvm.org/D52403
llvm-svn: 346855
DWARF5 spec describes a single file split dwarf case
(when .dwo sections are in the .o files).
Problem is that LLDB does not work correctly in that case.
The issue is that, for example, both .debug_info and .debug_info.dwo
has the same type: eSectionTypeDWARFDebugInfo. And when code searches
section by type it might find the regular debug section
and not the .dwo one.
The patch fixes that. With it, LLDB is able to work with
output compiled with -gsplit-dwarf=single flag correctly.
Differential revision: https://reviews.llvm.org/D52296
llvm-svn: 346848
Summary:
pcm files can end up being processed by lldb with relocations to be
made for the .debug_info section. When a R_AARCH64_ABS64 relocation
was required lldb would hit an `assert(false)` and die.
Add R_AARCH64_ABS64 relocations to the S+A 64 bit width code path. Add
a test for R_AARCH64_ABS64 and R_AARCH64_ABS32 .rela.debug_info
relocations in a pcm file.
Reviewers: sas, xiaobai, davide, javed.absar, espindola
Reviewed By: davide
Subscribers: labath, zturner, emaste, mgorny, arichardson, kristof.beyls
Differential Revision: https://reviews.llvm.org/D51566
llvm-svn: 346171
Summary:
This patch adds possibility of searching a public symbol with name and type in a
symbol file. It is helpful when working with PE, because PE's symtabs contain
only imported / exported symbols only. Such a search is required for e.g.
evaluation of an expression that calls some function of the debuggee.
Reviewers: zturner, asmith, labath, clayborg, espindola
Reviewed By: clayborg
Subscribers: emaste, arichardson, aleksandr.urakov, jingham, lldb-commits, stella.stamenova
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D53368
llvm-svn: 345957
This patch removes the logic for resolving paths out of FileSpec and
updates call sites to rely on the FileSystem class instead.
Differential revision: https://reviews.llvm.org/D53915
llvm-svn: 345890
This patch removes the GetByteSize method from FileSpec and updates its
uses with calls to the FileSystem.
Differential revision: https://reviews.llvm.org/D53788
llvm-svn: 345812
This implements the support for .debug_loclists section, which is
DWARF 5 version of .debug_loc.
Currently, clang is able to emit it with the use of D53365.
Differential revision: https://reviews.llvm.org/D53436
llvm-svn: 345016
This adds a basic support of the .debug_rnglists section.
Only the DW_RLE_start_length and DW_RLE_end_of_list entries are supported.
Differential revision: https://reviews.llvm.org/D52981
llvm-svn: 344119
This patch improves the support of DWARF5.
Particularly the reporting of source code locations.
Differential revision: https://reviews.llvm.org/D51935
llvm-svn: 342153
Summary:
.rela.debug_info relocations are being done via
ObjectFileELF::ApplyRelocations for aarch64. Currently, the switch case
that iterates over the relocation type is only implemented for a few
different types and `assert(false)`es over the rest.
Implement the relocation for R_AARCH64_ABS32 in ApplyRelocations
Reviewers: sas, xiaobai, javed.absar, espindola
Reviewed By: sas
Subscribers: emaste, arichardson, kristof.beyls
Differential Revision: https://reviews.llvm.org/D50369
Change by Nathan Lanza <lanza@fb.com>
llvm-svn: 339974
This change improves the logging for the lldb.module category to note a few interesting cases:
1. Local object file found, but specs not matching
2. Local object file not found, using a placeholder module
The handling and logging for the cases wehre we fail to load compressed dwarf
symbols is also improved.
Differential Revision: https://reviews.llvm.org/D50274
llvm-svn: 339161
Summary:
.rela.debug_info relocations are being done via
ObjectFileELF::ApplyRelocations for aarch64. Currently, the switch case
that iterates over the relocation type is only implemented for a few
different types and `assert(false)`es over the rest.
Implement the relocation for R_AARCH64_ABS32 in ApplyRelocations
Reviewers: sas, xiaobai, peter.smith, clayborg, javed.absar, espindola
Differential Revision: https://reviews.llvm.org/D49407
Change by Nathan Lanza <lanza@fb.com>
llvm-svn: 339068
Pavel Labath
Jonas Devlieghere
George Rimar
Davide Italiano
Nathan Lanza
Aleksandr Urakov
Stephane Sezer
Leonard Mosescu