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
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
`--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
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.
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
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
As seen in https://bugs.llvm.org/show_bug.cgi?id=52213 llvm-objdump
asserts if either the --debug-vars or the --dwarf options are provided
with invalid values. As suggested, this fix adds use of a default value
to these options and errors when given bad input.
Differential Revision: https://reviews.llvm.org/D112183
This moves the registry higher in the LLVM library dependency stack.
Every client of the target registry needs to link against MC anyway to
actually use the target, so we might as well move this out of Support.
This allows us to ensure that Support doesn't have includes from MC/*.
Differential Revision: https://reviews.llvm.org/D111454
Summary:
for xcoff :
implement the getSymbolFlag and getSymbolType() for option --syms.
llvm-objdump --sym , if the symbol is label, print the containing section for the symbol too.
when using llvm-objdump --sym --symbol--description, print the symbol index and qualname for symbol.
for example:
--symbol-description
00000000000000c0 l .text (csect: (idx: 2) .foov[PR]) (idx: 3) .foov
and without --symbol-description
00000000000000c0 l .text (csect: .foov) .foov
Reviewers: James Henderson,Esme Yi
Differential Revision: https://reviews.llvm.org/D109452
* Add a newline before `DYNAMIC RELOCATION RECORDS` (see D101796)
* Add the missing `OFFSET TYPE VALUE` line
* Align columns
Note: llvm-readobj/ELFDumper.cpp `loadDynamicTable` has sophisticated PT_DYNAMIC
code which is unavailable in llvm-objdump.
Reviewed By: jhenderson, Higuoxing
Differential Revision: https://reviews.llvm.org/D110595
Print relocations interleaved with disassembled instructions for
executables with relocatable sections, e.g. those built with "-Wl,-q".
Differential Revision: https://reviews.llvm.org/D109016
Similar to D94907 (llvm-nm -D).
The output will match GNU objdump 2.37.
Older versions don't use ` (version)` for undefined symbols.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D108097
[[noreturn]] can be used since Oct 2016 when the minimum compiler requirement was bumped to GCC 4.8/MSVC 2015.
Note: the definition of LLVM_ATTRIBUTE_NORETURN is kept for now.
If a file has no symbols, perhaps because it is a linked executable,
synthesize some symbols by walking the code section. Otherwise the
disassembler will try to treat the whole code section as a function,
which won't parse. Fixes https://bugs.llvm.org/show_bug.cgi?id=50957.
Differential Revision: https://reviews.llvm.org/D105539
The patch reuses the common code to print memory operand addresses as
instruction comments. This helps to align the comments and enables using
target-specific comment markers when `evaluateMemoryOperandAddress()` is
implemented for them.
Differential Revision: https://reviews.llvm.org/D104861
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
LLVM disassembler can generate comments for disassembled instructions.
The patch enables printing these comments for 'llvm-objdump -d'.
Differential Revision: https://reviews.llvm.org/D104699
This is a mechanical change. This actually also renames the
similarly named methods in the SmallString class, however these
methods don't seem to be used outside of the llvm subproject, so
this doesn't break building of the rest of the monorepo.
Summary: Under the option --section-headers, we can only
print the section types of TEXT, DATA, and BSS for now.
This patch adds the DEBUG type.
Reviewed By: jhenderson, Higuoxing
Differential Revision: https://reviews.llvm.org/D102603
This makes it possible for targets to define their own MCObjectFileInfo.
This MCObjectFileInfo is then used to determine things like section alignment.
This is a follow up to D101462 and prepares for the RISCV backend defining the
text section alignment depending on the enabled extensions.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D101921
`__mh_(execute|dylib|dylinker|bundle|preload|object)_header` are special symbols whose values hold the VMA of the Mach header to support introspection. They are attached to the first section in `__TEXT`, even though their addresses are outside `__TEXT`, and they do not refer to code.
It is normally harmless, but when the first section of `__TEXT` has no other symbols, `__mh_*_header` is considered by the disassembler when determing function boundaries. Since `__mh_*_header` refers to an address outside `__TEXT`, the boundary determination fails and disassembly quits.
Since `__TEXT,__text` normally has symbols, this bug is obscured. Experiments placing `__stubs` and `__stub_helper` first exposed the bug, since neither has symbols.
Differential Revision: https://reviews.llvm.org/D101786
Fix up my recent commit rG1128311a19179ceca799ff0fbc4dd206ab56e560 to
use std::make_unique instead of std::unique_ptr(new), as requested by
David Blaikie.
Differential Revision: https://reviews.llvm.org/D101822
This untangles the MCContext and the MCObjectFileInfo. There is a circular
dependency between MCContext and MCObjectFileInfo. Currently this dependency
also exists during construction: You can't contruct a MOFI without a MCContext
without constructing the MCContext with a dummy version of that MOFI first.
This removes this dependency during construction. In a perfect world,
MCObjectFileInfo wouldn't depend on MCContext at all, but only be stored in the
MCContext, like other MC information. This is future work.
This also shifts/adds more information to the MCContext making it more
available to the different targets. Namely:
- TargetTriple
- ObjectFileType
- SubtargetInfo
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D101462
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
