The main disassembly loop in llvm-objdump works by iterating through
the symbols in a code section, and for each one, dumping the range of
the section from that symbol to the next. If there's another symbol
defined at the same location, then that range will have length 0, and
llvm-objdump will skip over the symbol entirely.
As a result, llvm-objdump will only show the last of the symbols
defined at that address. Not only that, but the other symbols won't
even be checked against the `--disassemble-symbol` list. So if you
have two symbols `foo` and `bar` defined in the same place, then one
of `--disassemble-symbol=foo` and `--disassemble-symbol=bar` will
generate an error message and no disassembly.
I think a better approach in that situation is to prioritise display
of the symbol the user actually asked for. Also, if the user
specifically asks for disassembly of //both// of two symbols defined
at the same address, the best response I can think of is to
disassemble the code once, preceded by both symbol names.
This involves teaching llvm-objdump to be able to display more than
one symbol name at the head of a disassembled section, which also
makes it possible to implement a `--show-all-symbols` option to
display //every// symbol defined in the code, not just the most
preferred one at each address.
This change also turns out to fix a bug in which `--disassemble-all`
on a mixed Arm/Thumb ELF file would fail to switch disassembly states
between Arm and Thumb functions, because the mapping symbols were
accidentally ignored.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D131589
llvm-objdump takes foo-bar style flags, while llvm-otool takes foo_bar style
flags. dyld_info was the only exception to that.
Add a -dyld_info flag to llvm-otool instead.
(Both in llvm-objdump and llvm-otool, the flag doesn't really do anything
yet.)
Differential Revision: https://reviews.llvm.org/D131897
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
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
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
This change is to add some missing details, clarifies some options and
brings the help text and command guide of objdump closer together.
- Added to the help that --all-headers also outputs symbols and
relocations to match the command guide.
- Added to the help that --debug-vars accepts an optional
ascii/unicode format to match the command guide.
- Changed the help descriptions for --disassemble,
--disassemble-all, --dwarf=<value>, --fault-map-section,
--line-numbers, --no-leading-addr and --source descriptions to
match the command guide.
- Added to the help that --start-address and --stop-address also
effect relocation entries and the symbol table output to match
the command guide.
- Added a note to the command guide that --unwind-info and -u
are not available for the elf format.
Differential Revision: https://reviews.llvm.org/D110633
In the command guide --prefix and --prefix-strip is used in the form
--prefix=<prefix> however currently it is used in the form --prefix
<prefix>. This change fixes these options to match the command guide.
Differential Revision: https://reviews.llvm.org/D110551
Reapply 7368624 after revert and fix
Looking at other tools using tablegen for help output, general options
like --help are not separated from other options. This change removes
the "Generic Options" option group so the options are listed together.
the macho specific option group is left unaffected.
The test help.test was modified to reflect this change.
Differential Revision: https://reviews.llvm.org/D101652
Looking at other tools using tablegen for help output, general options
like --help are not separated from other options. This change removes
the "Generic Options" option group so the options are listed together.
the macho specific option group is left unaffected.
The test help.test was modified to reflect this change.
Differential Revision: https://reviews.llvm.org/D101652
This is similar to D83530, but for llvm-objdump.
The motivation is the desire to add an `llvm-otool` symlink to
llvm-objdump that behaves like macOS's `otool`, using the same
technique the at llvm-objcopy uses to behave like `strip` (etc).
This change for the most part preserves behavior. In some cases,
it increases compatibility with GNU objdump a bit. For example,
the long options now require two dashes, and the long options
taking arguments for the most part now require a `=` in front
of the value. Exceptions are flags where tests passed the
value separately, for these the separate form is kept as
an alias to the = form.
The one-letter short form args are now joined or separate
and long longer accept a =, which also matches GNU objdump.
cl::opt<>s in libraries now have to be explicitly plumbed
through. This patch does that for --x86-asm-syntax=, but
there's hope that we can remove that again.
Differential Revision: https://reviews.llvm.org/D100433
Simon Tatham