LLDB has a few different styles of header guards and they're not very
consistent because things get moved around or copy/pasted. This patch
unifies the header guards across LLDB and converts everything to match
LLVM's style.
Differential revision: https://reviews.llvm.org/D74743
Summary:
If the .symtab section is stripped from the binary it might be that
there's a .gnu_debugdata section which contains a smaller .symtab in
order to provide enough information to create a backtrace with function
names or to set and hit a breakpoint on a function name.
This change looks for a .gnu_debugdata section in the ELF object file.
The .gnu_debugdata section contains a xz-compressed ELF file with a
.symtab section inside. Symbols from that compressed .symtab section
are merged with the main object file's .dynsym symbols (if any).
In addition we always load the .dynsym even if there's a .symtab
section.
For example, the Fedora and RHEL operating systems strip their binaries
but keep a .gnu_debugdata section. While gdb already can read this
section, LLDB until this patch couldn't. To test this patch on a
Fedora or RHEL operating system, try to set a breakpoint on the "help"
symbol in the "zip" binary. Before this patch, only GDB can set this
breakpoint; now LLDB also can do so without installing extra debug
symbols:
lldb /usr/bin/zip -b -o "b help" -o "r" -o "bt" -- -h
The above line runs LLDB in batch mode and on the "/usr/bin/zip -h"
target:
(lldb) target create "/usr/bin/zip"
Current executable set to '/usr/bin/zip' (x86_64).
(lldb) settings set -- target.run-args "-h"
Before the program starts, we set a breakpoint on the "help" symbol:
(lldb) b help
Breakpoint 1: where = zip`help, address = 0x00000000004093b0
Once the program is run and has hit the breakpoint we ask for a
backtrace:
(lldb) r
Process 10073 stopped
* thread #1, name = 'zip', stop reason = breakpoint 1.1
frame #0: 0x00000000004093b0 zip`help
zip`help:
-> 0x4093b0 <+0>: pushq %r12
0x4093b2 <+2>: movq 0x2af5f(%rip), %rsi ; + 4056
0x4093b9 <+9>: movl $0x1, %edi
0x4093be <+14>: xorl %eax, %eax
Process 10073 launched: '/usr/bin/zip' (x86_64)
(lldb) bt
* thread #1, name = 'zip', stop reason = breakpoint 1.1
* frame #0: 0x00000000004093b0 zip`help
frame #1: 0x0000000000403970 zip`main + 3248
frame #2: 0x00007ffff7d8bf33 libc.so.6`__libc_start_main + 243
frame #3: 0x0000000000408cee zip`_start + 46
In order to support the .gnu_debugdata section, one has to have LZMA
development headers installed. The CMake section, that controls this
part looks for the LZMA headers and enables .gnu_debugdata support by
default if they are found; otherwise or if explicitly requested, the
minidebuginfo support is disabled.
GDB supports the "mini debuginfo" section .gnu_debugdata since v7.6
(2013).
Reviewers: espindola, labath, jankratochvil, alexshap
Reviewed By: labath
Subscribers: rnkovacs, wuzish, shafik, emaste, mgorny, arichardson, hiraditya, MaskRay, lldb-commits
Tags: #lldb, #llvm
Differential Revision: https://reviews.llvm.org/D66791
llvm-svn: 373891
Summary:
The contents of the gnu_debuglink section were passed through the
GetDebugSymbolFilePaths interface, which was more generic than needed.
As the only class implementing this function is ObjectFileELF, we can
modify the function to return just a single FileSpec (instead of a
list). Also, since the SymbolVendorELF already assumes ELF object files,
we don't have to make this method available on the generic ObjectFile
interface -- instead we can put it on ObjectFileELF directly.
This change also makes is so that if the Module has an explicit symbol
file spec set, we disregard the value the value of the debug link
(instead of doing a secondary lookup using that). I think it makes sense
to honor the users wishes if he had explicitly set the symbol file spec,
and this seems to be consistent with what SymbolVendorMacOSX is doing
(SymbolVendorMacOSX.cpp:125).
The main reason for making these changes is to make the treatment of
build-ids and debug links simpler in the follow-up patch.
Reviewers: clayborg, jankratochvil, mgorny, espindola
Subscribers: emaste, arichardson, MaskRay, lldb-commits
Differential Revision: https://reviews.llvm.org/D65560
llvm-svn: 367824
Summary:
On the heels of D62934, this patch uses the same approach to introduce
llvm RTTI support to the ObjectFile hierarchy. It also replaces the
existing uses of GetPluginName doing run-time type checks with
llvm::dyn_cast and friends.
This formally introduces new dependencies from some other plugins to
ObjectFile plugins. However, I believe this is fine because:
- these dependencies were already kind of there, and the only reason
we could get away with not modeling them explicitly was because the
code was relying on magically knowing what will GetPluginName() return
for a particular kind of object files.
- the dependencies themselves are logical (it makes sense for
SymbolVendorELF to depend on ObjectFileELF), or at least don't
actively get in the way (the JitLoaderGDB->MachO thing).
- they don't introduce any new dependency loops as ObjectFile plugins
don't depend on any other plugins
Reviewers: xiaobai, JDevlieghere, espindola
Subscribers: emaste, mgorny, arichardson, MaskRay, lldb-commits
Differential Revision: https://reviews.llvm.org/D65450
llvm-svn: 367413
Just delete the memset as the ELFHeader constructor already
zero-initializes the object. Also clean up the ObjectFileELF
constructors/desctructors while I'm in there.
llvm-svn: 366692
A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.
Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.
I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.
Differential revision: https://reviews.llvm.org/D60508
llvm-svn: 358135
The `ap` suffix is a remnant of lldb's former use of auto pointers,
before they got deprecated. Although all their uses were replaced by
unique pointers, some variables still carried the suffix.
In r353795 I removed another auto_ptr remnant, namely redundant calls to
::get for unique_pointers. Jim justly noted that this is a good
opportunity to clean up the variable names as well.
I went over all the changes to ensure my find-and-replace didn't have
any undesired side-effects. I hope I didn't miss any, but if you end up
at this commit doing a git blame on a weirdly named variable, please
know that the change was unintentional.
llvm-svn: 353912
instead of returning the UUID through by-ref argument and a boolean
value indicating success, we can just return it directly. Since the UUID
class already has an invalid state, it can be used to denote the failure
without the additional bool.
llvm-svn: 353714
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
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:
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
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
This patch removes the comments grouping header includes. They were
added after running IWYU over the LLDB codebase. However they add little
value, are often outdates and burdensome to maintain.
llvm-svn: 346626
This change allows to make AddressClass strongly typed enum and not to have issues with old versions of SWIG that don't support enum classes.
llvm-svn: 335710
This brings the LLDB configuration closer to LLVM's and removes visual
clutter in the source code by removing the @brief commands from
comments.
This patch also reflows the paragraphs in all doxygen comments.
See also https://reviews.llvm.org/D46290.
Differential Revision: https://reviews.llvm.org/D46321
llvm-svn: 331373
The difference between this and the previous patch is that now we use
ELF physical addresses only for loading objects into the target (and the
rest of the module load address logic still uses virtual addresses).
Summary:
When writing an object file over gdb-remote, use the vFlashErase, vFlashWrite, and vFlashDone commands if the write address is in a flash memory region. A bare metal target may have this kind of setup.
- Update ObjectFileELF to set load addresses using physical addresses. A typical case may be a data section with a physical address in ROM and a virtual address in RAM, which should be loaded to the ROM address.
- Add support for querying the target's qXfer:memory-map, which contains information about flash memory regions, leveraging MemoryRegionInfo data structures with minor modifications
- Update ProcessGDBRemote to use vFlash commands in DoWriteMemory when the target address is in a flash region
Original discussion at http://lists.llvm.org/pipermail/lldb-dev/2018-January/013093.html
Reviewers: clayborg, labath
Reviewed By: labath
Subscribers: llvm-commits, arichardson, emaste, mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D42145
Patch by Owen Shaw <llvm@owenpshaw.net>.
llvm-svn: 327970
This reverts commit r326261 as it introduces inconsistencies in the
handling of load addresses for ObjectFileELF -- some parts of the class
use physical addresses, and some use virtual. This has manifested itself
as us not being able to set the load address of the vdso "module" on
android.
llvm-svn: 326367
Summary:
When writing an object file over gdb-remote, use the vFlashErase, vFlashWrite, and vFlashDone commands if the write address is in a flash memory region. A bare metal target may have this kind of setup.
- Update ObjectFileELF to set load addresses using physical addresses. A typical case may be a data section with a physical address in ROM and a virtual address in RAM, which should be loaded to the ROM address.
- Add support for querying the target's qXfer:memory-map, which contains information about flash memory regions, leveraging MemoryRegionInfo data structures with minor modifications
- Update ProcessGDBRemote to use vFlash commands in DoWriteMemory when the target address is in a flash region
Original discussion at http://lists.llvm.org/pipermail/lldb-dev/2018-January/013093.html
Reviewers: clayborg, labath
Reviewed By: labath
Subscribers: arichardson, emaste, mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D42145
Patch by Owen Shaw <llvm@owenpshaw.net>
llvm-svn: 326261
Summary:
We use the llvm decompressor to decompress SHF_COMPRESSED sections. This enables
us to read data from debug info sections, which are sometimes compressed,
particuarly in the split-dwarf case. This functionality is only available if
llvm is compiled with zlib support.
Reviewers: clayborg, zturner
Subscribers: emaste, mgorny, aprantl, lldb-commits
Differential Revision: https://reviews.llvm.org/D40616
llvm-svn: 320813
The rationale here is that ArchSpec is used throughout the codebase,
including in places which should not depend on the rest of the code in
the Core module.
This commit touches many files, but most of it is just renaming of
#include lines. In a couple of cases, I removed the #include ArchSpec
line altogether, as the file was not using it. In one or two places,
this necessitated adding other #includes like lldb-private-defines.h.
llvm-svn: 318048
FreeBSD kernel modules are actually relocatable (.o) ELF files and this
previously caused some issues for LLDB. This change addresses these when
using lldb to symbolicate FreeBSD kernel backtraces.
The major problems:
- Relocations were not being applied to the DWARF debug info despite
there being code to do this. Several issues prevented it from working:
- Relocations are computed at the same time as the symbol table, but
in the case of split debug files, symbol table parsing always
redirects to the primary object file, meaning that relocations would
never be applied in the debug file.
- There's actually no guarantee that the symbol table has been parsed
yet when trying to parse debug information.
- When actually applying relocations, it will segfault because the
object files are not mapped with MAP_PRIVATE and PROT_WRITE.
- LLDB returned invalid results when performing ordinary address-to-
symbol resolution. It turned out that the addresses specified in the
section headers were all 0, so LLDB believed all the sections had
overlapping "file addresses" and would sometimes return a symbol from
the wrong section.
Patch by Brian Koropoff
Differential Revision: https://reviews.llvm.org/D38142
llvm-svn: 314672