Commit Graph

51 Commits

Author SHA1 Message Date
Daniel Thornburgh cc2457ca1b [llvm-objdump] Set --print-imm-hex by default.
This was previously attempted in 2016 by colinl's D18770, but LLD tests
were missed, which caused the change to be reverted.

Setting --print-imm-hex by default brings llvm-objdump's behavior closer
in line with objdump, and it makes it easier to read addresses and
alignment from the disassembly. It may make non-address immediates
harder to interpret, but it still seems the better default, barring more
context-sensitive base selection logic.

Differential Revision: https://reviews.llvm.org/D136972
2022-10-30 13:36:18 -07:00
Keith Smiley bc99fd95e0
[llvm-objdump/mac] Add new function starts print mode
This updates the `--function-starts` argument to now accept 3 different
modes, `addrs` for just printing the addresses of the function starts
(previous behavior), `names` for just printing the names of the function
starts, and `both` to print them both side by side.

In general if you're debugging function starts issues it's useful to see
the symbol name alongside the address. This also mirrors Apple's
`dyldinfo -function_starts` command which prints both.

Differential Revision: https://reviews.llvm.org/D119050
2022-10-14 15:42:18 -07:00
Daniel Thornburgh 2e91a5f546 [llvm-objdump] Add --build-id flag for debuginfod lookups without binary.
Adding a --build-id flag allows handling binaries that are referenced in
logs from remote systems, but that aren't necessarily present on the
local machine. These are fetched via debuginfod and handled as if they
were input filenames.

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D133992
2022-10-04 13:44:25 -07:00
Fangrui Song 5c7566cd05 [llvm-objdump] Add --no-addresses as an alias for --no-leading-addr
The output is similar to objdump --no-addresses since binutils 2.35.

Depends on D135039
Close #58088

Differential Revision: https://reviews.llvm.org/D135040
2022-10-04 10:01:30 -07:00
Fangrui Song ad92a3db2e [llvm-objdump] --no-leading-addr: hide inline relocation offsets
It seems to make sense to omit offsets when --no-leading-addr is specified. The output is now closer
to objdump -dr --no-addresses (non-wide output).

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D135039
2022-10-04 10:00:21 -07:00
Daniel Thornburgh d033ece0c9 [llvm-objdump] Find debug information with Build ID/debuginfod.
Uses the library introduced in https://reviews.llvm.org/D132504 to add build ID fetching to llvm-objdump. This allows viewing source when disassembling stripped objects.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D131224
2022-10-03 16:17:45 -07:00
Nico Weber 1642667392 [llvm-objdump --macho] Rename --dyld_info to --dyld-info
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
2022-08-17 12:58:29 -04:00
Nico Weber 940e178c00 [llvm-objdump] Start on -chained_fixups for llvm-otool
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
2022-08-15 10:58:52 -04:00
Joseph Huber ec2b040e18 [llvm-objdump][docs] Fix documentation for offloading flags 2022-07-11 15:44:48 -04:00
Joseph Huber 85768677f8 [llvm-objdump][Docs] Document new flag 2022-07-07 20:41:53 -04:00
Fangrui Song 2601b90d83 [llvm-objdump] Default to --mcpu=future for PPC64
GNU objdump disassembles all unknown instructions by default. Match this user
friendly behavior with the cpu value `future`.

Differential Revision: https://reviews.llvm.org/D127824
2022-06-30 11:30:35 -07:00
Fangrui Song 275862c75d [llvm-objdump] Default to --mattr=+all for AArch64
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
2022-06-30 11:17:56 -07:00
Rahman Lavaee 5f7ef65245 [llvm-objdump] Let --symbolize-operands symbolize basic block addresses based on the SHT_LLVM_BB_ADDR_MAP section.
`--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
2022-05-16 10:11:11 -07:00
Adrian Prantl 621e2de138 Add a (nonfunctional) -dyld_info flag to llvm-objdump.
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
2022-02-22 11:06:27 -08:00
Chuanqi Xu bbce75e352 Update Bug report URL to Github Issues
Although we moved to Github Issues. The bug report message refers to
Bugzilla still. This patch tries to update these URLs.

Reviewed By: MaskRay, Quuxplusone, jhenderson, libunwind, libc++

Differential Revision: https://reviews.llvm.org/D116351
2022-01-06 17:33:25 +08:00
Esme-Yi b66328701a [PowerPC][llvm-objdump] enable --symbolize-operands for PowerPC ELF/XCOFF.
Summary: When disassembling, symbolize a branch target operand
to print a label instead of a real address.

Reviewed By: shchenz

Differential Revision: https://reviews.llvm.org/D114492
2021-12-21 04:17:57 +00:00
Shao-Ce SUN 0c660256eb [NFC] Trim trailing whitespace in *.rst 2021-11-15 09:17:08 +08:00
gbreynoo 3a5aa57c9b [llvm-objdump][docs] Add details to the help output and command guide
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
2021-10-07 16:30:12 +01:00
Kazu Hirata 5294a0f7c3 [llvm] Fix typos in documentation (NFC) 2021-08-28 06:37:03 -07:00
gbreynoo a37f558682 [llvm-objdump] Add --no-print-imm-hex to the command guide
The option --no-print-imm-hex was not included in the command guide for
llvm-objdump but appears in the help text. This commit adds it to the
command guide.

Differential Revision: https://reviews.llvm.org/D104717
2021-06-29 17:18:32 +01:00
Igor Kudrin c2e6bcb494 [llvm-objdump] Prevent variable locations to overlap short comments
For now, the source variable locations are printed at about the same
space as the comments for disassembled code, which can make some ranges
for variables disappear if a line contains comments, for example:

                                        ┠─ bar = W1
0:  add x0, x2, #2, lsl #12     // =8192┃
4:  add z31.d, z31.d, #65280    // =0xff00
8:  nop                                 ┻

The patch shifts the report a bit to allow printing comments up to
approximately 16 characters without interferences.

Differential Revision: https://reviews.llvm.org/D104700
2021-06-28 14:25:21 +07:00
Fangrui Song 3f85e124f6 [docs] llvm-objdump: Mention -M no-aliases is supported on AArch64 2021-05-26 23:57:32 -07:00
Fangrui Song e510860656 [llvm-objdump] Add -M {att,intel} & deprecate --x86-asm-syntax={att,intel}
The internal `cl::opt` option --x86-asm-syntax sets the AsmParser and AsmWriter
dialect. The option is used by llc and llvm-mc tests to set the AsmWriter dialect.

This patch adds -M {att,intel} as GNU objdump compatible aliases (PR43413).

Note: the dialect is initialized when the MCAsmInfo is constructed.
`MCInstPrinter::applyTargetSpecificCLOption` is called too late and its MCAsmInfo
reference is const, so changing the `cl::opt` in
`MCInstPrinter::applyTargetSpecificCLOption` is not an option, at least without
large amount of refactoring.

Reviewed By: hoy, jhenderson, thakis

Differential Revision: https://reviews.llvm.org/D101695
2021-05-05 00:20:41 -07:00
gbreynoo 3273f27692 [llvm-objdump] Remove --cfg option from command guide
The llvm-objdump command guide has the option --cfg which was removed
from the tool by 888320e9fa in 2014. This
change updates the command guide to reflect this.

Differential Revision: https://reviews.llvm.org/D101648
2021-05-04 16:42:13 +01:00
Nick Desaulniers dde24a87c5 [llvm-objdump] add -v alias for --version
Used by the Linux kernel's CONFIG_X86_DECODER_SELFTEST.

Link: https://github.com/ClangBuiltLinux/linux/issues/1130

Reviewed By: MaskRay, jhenderson, rupprecht

Differential Revision: https://reviews.llvm.org/D101483
2021-04-30 11:26:36 -07:00
Keith Smiley 86b98c60c5 llvm-objdump: add --rpaths to macho support
This prints the rpaths for the given binary

Reviewed By: kastiglione

Differential Revision: https://reviews.llvm.org/D100681
2021-04-22 16:01:10 -07:00
Nico Weber 1a3f88658a [llvm-objdump] Add an llvm-otool tool
This implements an LLVM tool that's flag- and output-compatible
with macOS's `otool` -- except for bugs, but from testing with both
`otool` and `xcrun otool-classic`, llvm-otool matches vanilla
otool's behavior very well already. It's not 100% perfect, but
it's a very solid start.

This uses the same approach as llvm-objcopy: llvm-objdump uses
a different OptTable when it's invoked as llvm-otool. This
is possible thanks to D100433.

Differential Revision: https://reviews.llvm.org/D100583
2021-04-20 08:24:58 -04:00
Vinicius Tinti 804ff7f293 [llvm-objdump] Implement --prefix-strip option
The option `--prefix-strip` is only used when `--prefix` is not empty.
It removes N initial directories from absolute paths before adding the
prefix.

This matches GNU's objdump behavior.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D96679
2021-03-24 13:22:35 +00:00
Alexander Shaposhnikov 5f2f84a68a [llvm-objdump][MachO] Add support for dumping function starts
Add support for dumping function starts for Mach-O binaries.

Test plan: make check-all

Differential revision: https://reviews.llvm.org/D97027
2021-03-08 18:44:44 -08:00
David Spickett c2ead57ccf [llvm-objdump] Document --mattr=help in --help output
This does the same as `--mcpu=help` but was only
documented in the user guide.

* Added a test for both options.
* Corrected the single dash in `-mcpu=help` text.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D92305
2020-11-30 12:52:54 +00:00
Vinicius Tinti e95f9a23fa [llvm-objdump] Implement --prefix option
The prefix given to --prefix will be added to GNU absolute paths when
used with --source option (source interleaved with the disassembly).

This matches GNU's objdump behavior.

GNU and C++17 rules for absolute paths are different.

Differential Revision: https://reviews.llvm.org/D85024

Fixes PR46368.

Differential Revision: https://reviews.llvm.org/D85024
2020-10-16 17:50:42 +01:00
Hongtao Yu de0c7a044b [llvm-objdump] Attempt to fix html doc generation issue.
https://reviews.llvm.org/D84191 caused a html doc build issue with the changes in `llvm-objdump.rst`. It looks like a blank line is missing from the `code-block` directives.

Test Plan:

Differential Revision: https://reviews.llvm.org/D86123
2020-08-17 18:06:22 -07:00
Hongtao Yu 819b2d9c79 [llvm-objdump] Symbolize binary addresses for low-noisy asm diff.
When diffing disassembly dump of two binaries, I see lots of noises from mismatched jump target addresses and global data references, which unnecessarily causes diffs on every function, making it impractical. I'm trying to symbolize the raw binary addresses to minimize the diff noise.
In this change, a local branch target is modeled as a label and the branch target operand will simply be printed as a label. Local labels are collected by a separate pre-decoding pass beforehand. A global data memory operand will be printed as a global symbol instead of the raw data address. Unfortunately, due to the way the disassembler is set up and to be less intrusive, a global symbol is always printed as the last operand of a memory access instruction. This is less than ideal but is probably acceptable from checking code quality point of view since on most targets an instruction can have at most one memory operand.

So far only the X86 disassemblers are supported.

Test Plan:

llvm-objdump -d  --x86-asm-syntax=intel --no-show-raw-insn --no-leading-addr :
```
Disassembly of section .text:

<_start>:
               	push	rax
               	mov	dword ptr [rsp + 4], 0
               	mov	dword ptr [rsp], 0
               	mov	eax, dword ptr [rsp]
               	cmp	eax, dword ptr [rip + 4112]  # 202182 <g>
               	jge	0x20117e <_start+0x25>
               	call	0x201158 <foo>
               	inc	dword ptr [rsp]
               	jmp	0x201169 <_start+0x10>
               	xor	eax, eax
               	pop	rcx
               	ret
```

llvm-objdump -d  **--symbolize-operands** --x86-asm-syntax=intel --no-show-raw-insn --no-leading-addr :
```
Disassembly of section .text:

<_start>:
               	push	rax
               	mov	dword ptr [rsp + 4], 0
               	mov	dword ptr [rsp], 0
<L1>:
               	mov	eax, dword ptr [rsp]
               	cmp	eax, dword ptr  <g>
               	jge	 <L0>
               	call	 <foo>
               	inc	dword ptr [rsp]
               	jmp	 <L1>
<L0>:
               	xor	eax, eax
               	pop	rcx
               	ret
```

Note that the jump instructions like `jge 0x20117e <_start+0x25>` without this work is printed as a real target address and an offset from the leading symbol. With a change in the optimizer that adds/deletes an instruction, the address and offset may shift for targets placed after the instruction. This will be a problem when diffing the disassembly from two optimizers where there are unnecessary false positives due to such branch target address changes. With `--symbolize-operand`, a label is printed for a branch target instead to reduce the false positives. Similarly, the disassemble of PC-relative global variable references is also prone to instruction insertion/deletion.

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D84191
2020-08-17 16:55:12 -07:00
Oliver Stannard dc4a6f5db4 [llvm-objdump] Display locations of variables alongside disassembly
This adds the --debug-vars option to llvm-objdump, which prints
locations (registers/memory) of source-level variables alongside the
disassembly based on DWARF info. A vertical line is printed for each
live-range, with a label at the top giving the variable name and
location, and the position and length of the line indicating the program
counter range in which it is valid.

Differential revision: https://reviews.llvm.org/D70720
2020-07-09 09:58:00 +01:00
diggerlin a26a441b99 [llvm-objdump][XCOFF] Use symbol index+symbol name + storage mapping class as label for -D
SUMMARY:

For the llvm-objdump -D, the symbol name is used as a label in the disassembly for the specific address (when a symbol address is equal to the virtual address in the dump).

In XCOFF, multiple symbols may have the same name, being differentiated by their storage mapping class. It is helpful to print the QualName and not just the name when forming the output label for a csect symbol. The symbol index further removes any ambiguity caused by duplicate names.

To maintain compatibility with the binutils objdump, the XCOFF-specific --symbol-description option is added to enable the enhanced format.

Reviewers: hubert.reinterpretcast, James Henderson, Jason Liu ,daltenty
Subscribers: wuzish, nemanjai, hiraditya

Differential Revision: https://reviews.llvm.org/D72973
2020-04-06 10:10:10 -04:00
vgxbj 948ef5b1a6 [llvm-objdump] Teach `llvm-objdump` dump dynamic symbols.
Summary:
This patch is to teach `llvm-objdump` dump dynamic symbols (`-T` and `--dynamic-syms`). Currently, this patch is not fully compatible with `gnu-objdump`, but I would like to continue working on this in next few patches. It has two issues.

1. Some symbols shouldn't be marked as global(g). (`-t/--syms` has same issue as well) (Fixed by D75659)
2. `gnu-objdump` can dump version information and *dynamically* insert before symbol name field.

`objdump -T a.out` gives:

```
DYNAMIC SYMBOL TABLE:
0000000000000000  w   D  *UND*  0000000000000000              _ITM_deregisterTMCloneTable
0000000000000000      DF *UND*  0000000000000000  GLIBC_2.2.5 printf
0000000000000000      DF *UND*  0000000000000000  GLIBC_2.2.5 __libc_start_main
0000000000000000  w   D  *UND*  0000000000000000              __gmon_start__
0000000000000000  w   D  *UND*  0000000000000000              _ITM_registerTMCloneTable
0000000000000000  w   DF *UND*  0000000000000000  GLIBC_2.2.5 __cxa_finalize
```

`llvm-objdump -T a.out` gives:

```
DYNAMIC SYMBOL TABLE:
0000000000000000  w   D  *UND*  0000000000000000 _ITM_deregisterTMCloneTable
0000000000000000 g    DF *UND*  0000000000000000 printf
0000000000000000 g    DF *UND*  0000000000000000 __libc_start_main
0000000000000000  w   D  *UND*  0000000000000000 __gmon_start__
0000000000000000  w   D  *UND*  0000000000000000 _ITM_registerTMCloneTable
0000000000000000  w   DF *UND*  0000000000000000 __cxa_finalize
```

Reviewers: jhenderson, grimar, MaskRay, espindola

Reviewed By: jhenderson, grimar

Subscribers: emaste, rupprecht, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75756
2020-04-05 10:46:59 +08:00
Sylvestre Ledru 986051749c doc: use the right url to bugzilla 2020-03-22 22:49:40 +01:00
Sylvestre Ledru 72fd1033ea Doc: Links should use https 2020-03-22 22:49:33 +01:00
Nico Weber 9e48422035 Revert "[llvm-objdump] Display locations of variables alongside disassembly"
Makes tests fail on Windows, see https://reviews.llvm.org/D70720#1924542

This reverts commit 3a5ddedadb, and
follow-ups:
f4cb9c919e
042eb0482a
c0cf5f5da9
18649f4813
f62b898c1f
2020-03-16 14:04:25 -04:00
Oliver Stannard 3a5ddedadb [llvm-objdump] Display locations of variables alongside disassembly
This adds the --debug-vars option to llvm-objdump, which prints
locations (registers/memory) of source-level variables alongside the
disassembly based on DWARF info. A vertical line is printed for each
live-range, with a label at the top giving the variable name and
location, and the position and length of the line indicating the program
counter range in which it is valid.

Currently, this only works for object files, not executables or shared
libraries.

Differential revision: https://reviews.llvm.org/D70720
2020-03-16 10:54:40 +00:00
Fangrui Song 0d673be13a [llvm-objdump] Rename --disassemble-functions to --disassemble-symbols
https://bugs.llvm.org/show_bug.cgi?id=41910

The feature can disassemble data and the new option name reflects its
more generic usage.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D75816
2020-03-09 08:25:45 -07:00
James Henderson 778a5e5734 [docs] Make --version text more correct
Follow-up to r371983. Referring to "this program" in the description of
the --version option in the documentation isn't exactly correct, because
the docs are not part of the program, and so "this program" doesn't
really refer to anything. This patch brings the other users of this
terminology into line with the new updates to llvm-size and
llvm-strings.

Reviewed by: alexshap, MaskRay

Differential Revision: https://reviews.llvm.org/D67618

llvm-svn: 372107
2019-09-17 11:43:42 +00:00
James Henderson 8447b419a7 [docs][llvm-objdump] Make some wording improvements/simplifications.
llvm-svn: 365474
2019-07-09 12:41:39 +00:00
Yuanfang Chen 2dcd2c2493 [llvm-objdump] Update the doc for --disassemble-functions.
Update the doc after llvm-svn: 364121 is landed.
With two more trivial fixes that are not related to
--disassemble-functions but still about llvm-objdump.

Reviewers: jhenderson, grimar, MaskRay, rupprecht, peter.smith

Reviewed by: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D63787

llvm-svn: 364573
2019-06-27 18:39:34 +00:00
James Henderson 92b32a9087 [docs][llvm-nm][llvm-objdump] Improve "See Also" section
The "See Also" section for llvm-nm didn't actually contain any links,
and the tools referred to didn't make much sense (referring to non-LLVM
tools, when we have equivalents, or tools that aren't really to do with
symbol dumping). llvm-objdump's didn't refer to llvm-readelf.

Reviewed by: grimar

Differential Revision: https://reviews.llvm.org/D63875

llvm-svn: 364552
2019-06-27 15:18:15 +00:00
James Henderson a056684c33 [docs][tools] Add missing "program" tags to rst files
Sphinx allows for definitions of command-line options using
`.. option <name>` and references to those options via `:option:<name>`.
However, it looks like there is no scoping of these options by default,
meaning that links can end up pointing to incorrect documents. See for
example the llvm-mca document, which contains references to -o that,
prior to this patch, pointed to a different document. What's worse is
that these links appear to be non-deterministic in which one is picked
(on my machine, some references end up pointing to opt, whereas on the
live docs, they point to llvm-dwarfdump, for example).

The fix is to add the .. program <name> tag. This essentially namespaces
the options (definitions and references) to the named program, ensuring
that the links are kept correct.

Reviwed by: andreadb

Differential Revision: https://reviews.llvm.org/D63873

llvm-svn: 364538
2019-06-27 13:24:46 +00:00
James Henderson f7212dbe2f [docs][llvm-objdump] Fix bad merge of docs
llvm-svn: 364056
2019-06-21 14:41:36 +00:00
James Henderson 9485b265e8 [binutils] Add response file option to help and docs
Many LLVM-based tools already support response files (i.e. files
containing a list of options, specified with '@'). This change simply
updates the documentation and help text for some of these tools to
include it. I haven't attempted to fix all tools, just a selection that
I am interested in.

I've taken the opportunity to add some tests for --help behaviour, where
they were missing. We could expand these tests, but I don't think that's
within scope of this patch.

This fixes https://bugs.llvm.org/show_bug.cgi?id=42233 and
https://bugs.llvm.org/show_bug.cgi?id=42236.

Reviewed by: grimar, MaskRay, jkorous

Differential Revision: https://reviews.llvm.org/D63597

llvm-svn: 364036
2019-06-21 11:49:20 +00:00
James Henderson a8ed354b64 [docs][llvm-objdump] Improve llvm-objdump documentation
The llvm-objdump document was missing many options, and there were also
some style issues with it. This patches fixes all but the first issue
listed in https://bugs.llvm.org/show_bug.cgi?id=42249 by:

    1. Adding missing options and commands.
    2. Standardising on double dashes for long-options throughout.
    3. Moving Mach-O specific options to a separate section.
    4. Removing options that don't exist or aren't relevant to
       llvm-objdump.

Reviewed by: MaskRay, mtrent, alexshap

Differential Revision: https://reviews.llvm.org/D63606

llvm-svn: 364019
2019-06-21 10:12:53 +00:00
Michael Trent 7e6602110b llvm-objdump -m -D should disassemble all text segments
Summary:
When running llvm-objdump with the -macho option objdump will by default
disassemble only the __TEXT,__text section (or __TEXT_EXEC,__text when
disassembling MH_KEXT_BUNDLE files). The -disassemble-all option is
treated no diferently than -disassemble.

This change upates llvm-objdump's MachO parsing code to disassemble all
__text sections found in a file when -disassemble-all is specified. This
is useful for disassembling files with more than one __text section, or
when disassembling files whose __text section is not present in __TEXT.

I added a lit test case that verifies "llvm-objdump -m -d" and 
"llvm-objdump -m -D" produce the expected results on a reference binary. 
I also updated the CommandGuide documentation for llvm-objdump.rst and
verified it renders correctly as man and html.

rdar://42899338

Reviewers: ab, pete, lhames

Reviewed By: lhames

Subscribers: rupprecht, llvm-commits

Differential Revision: https://reviews.llvm.org/D56649

llvm-svn: 351238
2019-01-15 20:41:30 +00:00