And --chained-fixups for llvm-objdump.
For now, this only prints the dyld_chained_fixups_header and adds
plumbing for the flag. This will be expanded in future commits.
When Apple's effort to upstream their chained fixups code continues,
we'll replace this code with the then-upstreamed code. But we need
something in the meantime for testing ld64.lld's chained fixups
code.
Update chained-fixups.yaml with a file that actually contains
the chained fixup data (`LinkEditData` doesn't encode it yet,
so use `__LINKEDIT` via `--raw-segment=data`).
Differential Revision: https://reviews.llvm.org/D131890
The ABI for big-endian AArch32, as specified by AAELF32, is above-
averagely complicated. Relocatable object files are expected to store
instruction encodings in byte order matching the ELF file's endianness
(so, big-endian for a BE ELF file). But executable images can
//either// do that //or// store instructions little-endian regardless
of data and ELF endianness (to support BE32 and BE8 platforms
respectively). They signal the latter by setting the EF_ARM_BE8 flag
in the ELF header.
(In the case of the Thumb instruction set, this all means that each
16-bit halfword of a Thumb instruction is stored in one or other
endianness. The two halfwords of a 32-bit Thumb instruction must
appear in the same order no matter what, because the first halfword is
the one that must avoid overlapping the encoding of any 16-bit Thumb
instruction.)
llvm-objdump was unconditionally expecting Arm instructions to be
stored little-endian. So it would correctly disassemble a BE8 image,
but if you gave it a BE32 image or a BE object file, it would retrieve
every instruction in byte-swapped form and disassemble it to
nonsense. (Even an object file output by LLVM itself, because
ARMMCCodeEmitter outputs instructions big-endian in big-endian mode,
which is correct for writing an object file.)
This patch allows llvm-objdump to correctly disassemble all three of
those classes of Arm ELF file. It does it by introducing a new
SubtargetFeature for big-endian instructions, setting it from the ELF
image type and flags during llvm-objdump setup, and teaching both
ARMDisassembler and llvm-objdump itself to pay attention to it when
retrieving instruction data from a section being disassembled.
Differential Revision: https://reviews.llvm.org/D130902
The whitespace in output lines containing disassembled instructions
was extremely mismatched against that in `.word` lines produced from
dumping literal pools and other data in Arm ELF files. This patch
adjusts `dumpARMELFData` so that it uses the same alignment system as
in the instruction pretty-printers. Now the two classes of line are
aligned sensibly alongside each other.
Reviewed By: DavidSpickett
Differential Revision: https://reviews.llvm.org/D130359
Most Arm disassemblers, including GNU objdump and Arm's own `fromelf`,
emit an instruction's raw encoding as a 32-bit words or (for Thumb)
one or two 16-bit halfwords, in logical order rather than according to
their storage endianness. This is generally easier to read: it matches
the encoding diagrams in the architecture spec, it matches the value
you'd write in a `.inst` directive, and it means that fields within
the instruction encoding that span more than one byte (such as branch
offsets or `SVC` immediates) can be read directly in the encoding
without having to mentally reverse the bytes.
llvm-objdump already has a system of PrettyPrinter subclasses which
makes it easy for a target to drop in its own preferred formatting.
This patch adds pretty-printers for all the Arm targets, so that
llvm-objdump will display Arm instruction encodings in their preferred
layout instead of little-endian and bytewise.
Reviewed By: DavidSpickett
Differential Revision: https://reviews.llvm.org/D130358
Currently, when llvm-objdump is disassembling a code section and
encounters a point where no instruction can be decoded, it uses the
same policy on all targets: consume one byte of the section, emit it
as "<unknown>", and try disassembling from the next byte position.
On an architecture where instructions are always 4 bytes long and
4-byte aligned, this makes no sense at all. If a 4-byte word cannot be
decoded as an instruction, then the next place that a valid
instruction could //possibly// be found is 4 bytes further on.
Disassembling from a misaligned address can't possibly produce
anything that the code generator intended, or that the CPU would even
attempt to execute.
This patch introduces a new MCDisassembler virtual method called
`suggestBytesToSkip`, which allows each target to choose its own
resynchronization policy. For Arm (as opposed to Thumb) and AArch64,
I've filled in the new method to return a fixed width of 4.
Thumb is a more interesting case, because the criterion for
identifying 2-byte and 4-byte instruction encodings is very simple,
and doesn't require the particular instruction to be recognized. So
`suggestBytesToSkip` is also passed an ArrayRef of the bytes in
question, so that it can take that into account. The new test case
shows Thumb disassembly skipping over two unrecognized instructions,
and identifying one as 2-byte and one as 4-byte.
For targets other than Arm and AArch64, this is NFC: the base class
implementation of `suggestBytesToSkip` still returns 1, so that the
existing behavior is unchanged. Other targets can fill in their own
implementations as they see fit; I haven't attempted to choose a new
behavior for each one myself.
I've updated all the call sites of `MCDisassembler::getInstruction` in
llvm-objdump, and also one in sancov, which was the only other place I
spotted the same idiom of `if (Size == 0) Size = 1` after a call to
`getInstruction`.
Reviewed By: DavidSpickett
Differential Revision: https://reviews.llvm.org/D130357
The clause in `dumpARMELFData` that dumps a single byte as a `.byte`
directive was printing the operand of that directive as `Bytes[0]`,
not `Bytes[Index]`. In particular, this led to the `dumpBytes` output
to its left not matching it!
Reviewed By: DavidSpickett
Differential Revision: https://reviews.llvm.org/D130360
When linking, using `-Wl,-z,keep-text-section-prefix` results in multiple text sections while all `SHT_LLVM_BB_ADDR_MAP` sections are linked into a single one.
In such case, we should not read the corresponding section for each text section, and instead read all `SHT_LLVM_BB_ADDR_MAP` sections before disassembly.
Reviewed By: jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D129924
The linux perf tools use /proc/kcore for disassembly kernel functions.
Actually it copies the relevant parts to a temp file and then pass it to
objdump. But it doesn't have section headers so llvm-objdump cannot
handle it.
Let's create fake section headers for the program headers. It'd have a
single section for each segment to cover the entire range. And for this
purpose we can consider only executable code segments.
With this change, I can see the following command shows proper outputs.
perf annotate --stdio --objdump=/path/to/llvm-objdump
Differential Revision: https://reviews.llvm.org/D128705
Summary:
The `.llvm.offloading` section should always be aligned by `8`. However,
we may want to show the offloading data stored in a static library. In
this case, even though the section's alignment is correct, the offset
inside the archive will result in the memory buffer being misaligned. TO
combat this we simply check if the buffer does not have the proper
alignment and copies it to a new buffer if not. This copy should have
the proper alignment.
In order to be more in-line with ELF semantics, a previous patch added
support for a new ELF section type to indicate if a section contains
offloading data. This allows us to now check using this rather than
checking the section name directly. This patch updates the logic to
check the type now instead.
I chose to make this emit a warning if the input is not an ELF-object
file. I could have made the logic fall-back to the section name, but
this offloading in LLVM is currently not supported on any other targets
so it's probably best to emit a warning until we improve support.
Depends on D129052
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D129053
In Clang/LLVM we are moving towards a new binary format to store many
embedded object files to create a fatbinary. This patch adds support for
dumping these embedded images in the `llvm-objdump` tool. This will
allow users to query information about what is stored inside the binary.
This has very similar functionality to the `cuobjdump` tool for thoe familiar
with the Nvidia utilities. The proposed use is as follows:
```
$ clang input.c -fopenmp --offload-arch=sm_70 --offload-arch=sm_52 -c
$ llvm-objdump -O input.o
input.o: file format elf64-x86-64
OFFLOADIND IMAGE [0]:
kind cubin
arch sm_52
triple nvptx64-nvidia-cuda
producer openmp
OFFLOADIND IMAGE [1]:
kind cubin
arch sm_70
triple nvptx64-nvidia-cuda
producer openmp
```
This will be expanded further once we start embedding more information
into these offloading images. Right now we are planning on adding
flags and entries for debug level, optimization, LTO usage, target
features, among others.
This patch only supports printing these sections, later we will want to
support dumping files the user may be interested in via another flag. I
am unsure if this should go here in `llvm-objdump` or `llvm-objcopy`.
Reviewed By: MaskRay, tra, jhenderson, JonChesterfield
Differential Revision: https://reviews.llvm.org/D126904
ET_EXEC and ET_DYN files may contain non-SHF_ALLOC relocation sections
(e.g. ld --emit-relocs). Match GNU objdump by dumping them.
* Remove Object/dynamic-reloc.test. Replace it with a -r RUN line in dynamic-relocs.test
* Update relocations-in-nonreloc.test to set sh_link/sh_info. GNU
objdump seems to ignore a SHT_REL/SHT_RELA section not linking to SHT_SYMTAB.
The test did not test what it intended to test.
Fix https://github.com/llvm/llvm-project/issues/41246
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D128959
GNU objdump disassembles all unknown instructions by default. Match this user
friendly behavior with the target feature "all" (D128029) designed for disassemblers.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D128030
When loading split debug files for PE/COFF executables (produced with
`objcopy --only-keep-debug`), the tables or directories in such files
may point to data inside sections that may have been stripped.
COFFObjectFile shall detect and gracefully handle this, to allow the
object file be loaded without considering these tables or directories.
This is required for LLDB to load these files for use as debug symbols.
COFFObjectFile shall also check these pointers more carefully to account
for cases in which the section contains less raw data than the size
given by VirtualSize, to prevent going out of bounds.
This commit also changes COFFDump in llvm-objdump to reuse the pointers
that are already range-checked in COFFObjectFile. This fixes a crash
when trying to dump the TLS directory from a stripped file.
Fixes https://github.com/mstorsjo/llvm-mingw/issues/284
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D126898
MCSymbolizer::tryAddingSymbolicOperand() overloaded the Size parameter
to specify either the instruction size or the operand size depending on
the architecture. However, for proper symbolic disassembly on X86, we
need to know both sizes, as an instruction can have two operands, and
the instruction size cannot be reliably calculated based on the operand
offset and its size. Hence, split Size into OpSize and InstSize.
For X86, the new interface allows to fix a couple of issues:
* Correctly adjust the value of PC-relative operands.
* Set operand size to zero when the operand is specified implicitly.
Differential Revision: https://reviews.llvm.org/D126101
`--symbolize-operands` already symbolizes branch targets based on the disassembly. When the object file is created with `-fbasic-block-sections=labels` (ELF-only) it will include a SHT_LLVM_BB_ADDR_MAP section which maps basic blocks to their addresses. In such case `llvm-objdump` can annotate the disassembly based on labels inferred on this section.
In contrast to the current labels, SHT_LLVM_BB_ADDR_MAP-based labels are created for every machine basic block including empty blocks and those which are not branched into (fallthrough blocks).
The old logic is still executed even when the SHT_LLVM_BB_ADDR_MAP section is present to handle functions which have not been received an entry in this section.
Reviewed By: jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D124560
Namely, only "symbolize" platform and tool names if `-v` is passed.
(`llvm-otool -lv` output still isn't quite the same as `otool -lv` output, but
`-v` output is arguably for consumption by humans, so I'm not changing that
at this point. Someone else could change it if it was important to them.)
Differential Revision: https://reviews.llvm.org/D124920
Fix#54456: `objcopy --only-keep-debug` produces a linked image with invalid
empty dynamic section. llvm-objdump -p currently reports an error which seems
excessive.
```
% llvm-readelf -l a.out
llvm-readelf: warning: 'a.out': no valid dynamic table was found
...
```
Follow the spirit of llvm-readelf -l (D64472) and report a warning instead.
This allows later files to be dumped despite warnings for an input file, and
improves objdump compatibility in that the exit code is now 0 instead of 1.
```
% llvm-objdump -p a.out # new behavior
...
Program Header:
llvm-objdump: warning: 'a.out': invalid empty dynamic section
% objdump -p a.out
...
Dynamic Section:
```
Reviewed By: jhenderson, raj.khem
Differential Revision: https://reviews.llvm.org/D122505
Add processing of parsing and emiting lrw/jsri/jmpi instruction, including related fixup and relocation.
Add relax support about pseudo instructions such as jbr/jbsr.
Add objdump format support like arm in llvm-objdump.
This is causing
../../llvm/include/llvm/Object/MachO.h:379:13: warning: private field 'Kind' is not used [-Wunused-private-field]
FixupKind Kind;
Previous attempt in a23f7c0cb6.
This is part of a series of patches to upstream support for Mach-O chained fixups.
This patch adds support for parsing the chained fixup load command and
parsing the chained fixups header. It also puts into place the
abstract interface that will be used to iterate over the fixups.
Differential Revision: https://reviews.llvm.org/D113630
Darwin otool implements this flag as a one-stop solution for
displaying bind and rebase info. As I am working on upstreaming
chained fixup support this command will be useful to write testcases.
Differential Revision: https://reviews.llvm.org/D113573
the same address by symbol types.
Summary: In XCOFF, each section comes with a default symbol
with the same name as the section. It doesn't bind
to code locations and it may cause incorrect display
of symbol names under `llvm-objdump -d`.
This patch changes the priority of symbols with the
same address by symbol type.
Reviewed By: jhenderson, shchenz
Differential Revision: https://reviews.llvm.org/D117642
As usual with that header cleanup series, some implicit dependencies now need to
be explicit:
llvm/DebugInfo/DWARF/DWARFContext.h no longer includes:
- "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
- "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
- "llvm/DebugInfo/DWARF/DWARFDebugAbbrev.h"
- "llvm/DebugInfo/DWARF/DWARFDebugAranges.h"
- "llvm/DebugInfo/DWARF/DWARFDebugFrame.h"
- "llvm/DebugInfo/DWARF/DWARFDebugLoc.h"
- "llvm/DebugInfo/DWARF/DWARFDebugMacro.h"
- "llvm/DebugInfo/DWARF/DWARFGdbIndex.h"
- "llvm/DebugInfo/DWARF/DWARFSection.h"
- "llvm/DebugInfo/DWARF/DWARFTypeUnit.h"
- "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
Plus llvm/Support/Errc.h not included by a bunch of llvm/DebugInfo/DWARF/DWARF*.h files
Preprocessed lines to build llvm on my setup:
after: 1065629059
before: 1066621848
Which is a great diff!
Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D119723
Most notably,
llvm/Object/Binary.h no longer includes llvm/Support/MemoryBuffer.h
llvm/Object/MachOUniversal*.h no longer include llvm/Object/Archive.h
llvm/Object/TapiUniversal.h no longer includes llvm/Object/TapiFile.h
llvm-project preprocessed size:
before: 1068185081
after: 1068324320
Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D119457
If you're building this on macOS 12.x+ this produces a deprecation
warning. I'm not sure what this means for the bitcode format going
forward, but it seems safe to silence for now.
Differential Revision: https://reviews.llvm.org/D118569
This reverts commit ef82063207.
- It conflicts with the existing llvm::size in STLExtras, which will now
never be called.
- Calling it without llvm:: breaks C++17 compat
This reverts commit fd4808887e.
This patch causes gcc to issue a lot of warnings like:
warning: base class ‘class llvm::MCParsedAsmOperand’ should be
explicitly initialized in the copy constructor [-Wextra]
Nico Weber