* 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
D78776 removed is{Call,Branch,UnconditionalBranch} guards in objdump
before calling MCInstrAnalysis::evaluateBranch. This is fine for other
architectures as they gracefully handle evaluateBranch being called on
non-branches. However, the Lanai MCInstrAnalysis implementation didn't
and that change caused it to crash.
This inserts the same guards back into Lanai's evaluateBranch
implementation and adds a smoke test that exercises `llc | objdump` so
this kind of regression is hopefully caught next time.
Reviewed By: jpienaar, MaskRay
Differential Revision: https://reviews.llvm.org/D107593
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
Support XCOFFDumper relocation reading support
This patch is part of D103696 partition
Reviewed By: daltenty, Helflym
Differential Revision: https://reviews.llvm.org/D104646
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
This implements `MCInstrAnalysis::evaluateMemoryOperandAddress()` for
Arm so that the disassembler can print the target address of memory
operands that use PC+immediate addressing.
Differential Revision: https://reviews.llvm.org/D105979
Add a comment when there is a shifted value,
add x9, x0, #291, lsl #12 ; =1191936
but not when the immediate value is unshifted,
subs x9, x0, #256 ; =256
when the comment adds nothing additional to the reader.
Differential Revision: https://reviews.llvm.org/D107196
Apparently, the features were getting mixed up, so we'd try to
disassemble in ARM mode. Fix sub-architecture detection to compute the
correct triple if we're detecting it automatically, so the user doesn't
need to pass --triple=thumb etc.
It's possible we should be somehow tying the "+thumb-mode" target
feature more directly to Tag_CPU_arch_profile? But this seems to work
reasonably well, anyway.
While I'm here, fix up the other llvm-objdump tests that were explicitly
specifying an ARM triple; that shouldn't be necessary.
Differential Revision: https://reviews.llvm.org/D106912
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
By using stable_sort.
Added a test case which previously failed when expensive checks were
enabled.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D105240
llvm-objdump had some missing coverage that is fixed by this change:
- A test specifically for --print-imm-hex, and coverage of --no-print-imm-hex
- section-headers.test checks the aliases --headers or --section-headers
- A test for the use of --private-headers for ELF that checks the output
- A test for ELF program headers
Differential Revision: https://reviews.llvm.org/D103974
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
The instruction can be 16-bit aligned while targeting 32-bit aligned
code. To calculate the target address correctly, the address of the
instruction has to be adjusted.
Differential Revision: https://reviews.llvm.org/D104446
Summary: Add support for dumping line number
information for XCOFF object files in llvm-objdump.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D101272
Summary: This a minor patch to refactor the test file,
llvm-objdump/XCOFF/section-headers.test, to use yaml2obj
for this testing rather than a canned binary.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D103146
Add in the ability of parsing symbol table for 64 bit object.
Reviewed By: jhenderson, DiggerLin
Differential Revision: https://reviews.llvm.org/D85774
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
`__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
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
When dumping multiple pieces of information (e.g. --all-headers),
there is sometimes no separator between two pieces.
This patch uses the "\nheader:\n" style, which generally improves
compatibility with GNU objdump.
Note: objdump -t/-T does not add a newline before "SYMBOL TABLE:" and "DYNAMIC SYMBOL TABLE:".
We add a newline to be consistent with other information.
`objdump -d` prints two empty lines before the first 'Disassembly of section'.
We print just one with this patch.
Differential Revision: https://reviews.llvm.org/D101796
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
Previously printing R_386_RELATIVE relocations would trigger
`error: can't read an entry at 0x40: it goes past the end of the section (0x40)`
I found this while writing a test case for LLD (D100490).
This also includes some minor cleanup in the elf-dynamic-relcos.test
llvm-objdump test based on the newly added test.
Reviewed By: jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D100489
1. Add an accessor function to MCSymbolizer to retrieve addresses
referenced by a symbolizable operand, but not resolved to a symbol.
That way, the caller can synthesize labels at those addresses and
then retry disassembling the section.
2. Implement that in AMDGPU -- a failed symbol lookup results in the
address being added to a vector returned by the new function.
3. Use that in llvm-objdump when using MCSymbolizer (which only happens
on AMDGPU) and SymbolizeOperands is on.
Differential Revision: https://reviews.llvm.org/D101145
Change-Id: I19087c3bbfece64bad5a56ee88bcc9110d83989e
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
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
Clang spends a decent amount of time in the LineOffsetMapping::get(...)
function. This function used to be vectorized (through SSE2) then the
optimization got dropped because the sequential version was on-par performance
wise.
This provides an optimization of the sequential version that works on a word at
a time, using (documented) bithacks to provide a portable vectorization.
When preprocessing the sqlite amalgamation, this yields a sweet 3% speedup.
Differential Revision: https://reviews.llvm.org/D99409
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
llvm-objdump only uses one MCInstrAnalysis object, so if ARM and Thumb
code is mixed in one object, or if an object is disassembled without
explicitly setting the triple to match the ISA used, then branch and
call targets will be printed incorrectly.
This could be fixed by creating two MCInstrAnalysis objects in
llvm-objdump, like we currently do for SubtargetInfo. However, I don't
think there's any reason we need two separate sub-classes of
MCInstrAnalysis, so instead these can be merged into one, and the ISA
determined by checking the opcode of the instruction.
Differential revision: https://reviews.llvm.org/D97766
ST_Data is used to model BFD `BFD_OBJECT`.
A STT_TLS symbol does not have the `BFD_OBJECT` flag in BFD.
This makes sense because a STT_TLS symbol is like in a different address space,
normal data/object properties do not apply on them.
With this change, a STT_TLS symbol will not be displayed as 'O'.
This new behavior matches objdump.
Differential Revision: https://reviews.llvm.org/D96735
Merging directories and files may produce different results on different
platforms.
Merging "./Inputs" and "source-interleave-x86_64.c" will use different
separators in POSIX and Windows.
Dedicated tests are needed for dealing with removing trailing separators
for POSIX (consider only '/') and Windows (consider '/' and '\').
Fixes D85024.
Fixes PR46368.
Reviewed By: jhenderson, MaskRay
Differential revision: https://reviews.llvm.org/D95513
Warnings have been added for three cases (PR41905): (1) missing debug info, (2)
the source file cannot be found, (3) the debug info points at a line beyond the
end of the file.
(1) is probably less useful. This was brought up once on
http://lists.llvm.org/pipermail/llvm-dev/2020-April/141264.html and two
internal users mentioned it to me that it was annoying. (I personally
find the warning confusing, too.)
Users specify --source to get additional information if sources happen to be
available. If sources are not available, it should be obvious as the output
will have no interleaved source lines. The warning can be especially annoying
when using llvm-objdump -S on a bunch of files.
This patch drops the warning when there is no debug info.
(If LLVMSymbolizer::symbolizeCode returns an `Error`, there will still be
an error. There is currently no test for an `Error` return value.
The only code path is probably a broken symbol table, but we probably already emit a warning
in that case)
`source-interleave-prefix.test` has an inappropriate "malformed" test - the test simply has no
.debug_* because new llc does not produce debug info when the filename is empty (invalid).
I have tried tampering the header of .debug_info/.debug_line but llvm-symbolizer does not warn.
This patch does not intend to add the missing test coverage.
Differential Revision: https://reviews.llvm.org/D88715
For x86-64 the REX.w prefix takes precedence over any other size
override (i.e. 0x66). Therefore, for x86-64 when REX.w is present set
'hasOpSize' to false to ensure that any size override is ignored.
Fixes PR48901.
Differential Revision: https://reviews.llvm.org/D95682
Compact unwind entries have 8 bits for the encoding-table offset:
* offsets 0..126 reference the global commmon-encodings table, while
* offsets 127..255 reference a per-second-level-page table.
This diff teaches `llvm-objdump` to print this per-page encodings table.
Differential Revision: https://reviews.llvm.org/D93265
This patch adds the ability to evaluate the state machine for CIE and FDE unwind objects and produce a UnwindTable with all UnwindRow objects needed to unwind registers. It will also dump the UnwindTable for each CIE and FDE when dumping DWARF .debug_frame or .eh_frame sections in llvm-dwarfdump or llvm-objdump. This allows users to see what the unwind rows actually look like for a given CIE or FDE instead of just seeing a list of opcodes.
This patch adds new classes: UnwindLocation, RegisterLocations, UnwindRow, and UnwindTable.
UnwindLocation is a class that describes how to unwind a register or Call Frame Address (CFA).
RegisterLocations is a class that tracks registers and their UnwindLocations. It gets populated when parsing the DWARF call frame instruction opcodes for a unwind row. The registers are mapped from their register numbers to the UnwindLocation in a map.
UnwindRow contains the result of evaluating a row of DWARF call frame instructions for the CIE, or a row from a FDE. The CIE can produce a set of initial instructions that each FDE that points to that CIE will use as the seed for the state machine when parsing FDE opcodes. A UnwindRow for a CIE will not have a valid address, whille a UnwindRow for a FDE will have a valid address.
The UnwindTable is a class that contains a sorted (by address) vector of UnwindRow objects and is the result of parsing all opcodes in a CIE, or FDE. Parsing a CIE should produce a UnwindTable with a single row. Parsing a FDE will produce a UnwindTable with one or more UnwindRow objects where all UnwindRow objects have valid addresses. The rows in the UnwindTable will be sorted from lowest Address to highest after parsing the state machine, or an error will be returned if the table isn't sorted. To parse a UnwindTable clients can use the following methods:
static Expected<UnwindTable> UnwindTable::create(const CIE *Cie);
static Expected<UnwindTable> UnwindTable::create(const FDE *Fde);
A valid table will be returned if the DWARF call frame instruction opcodes have no encoding errors. There are a few things that can go wrong during the evaluation of the state machine and these create functions will catch and return them.
Differential Revision: https://reviews.llvm.org/D89845
This makes the following improvements.
For `SHT_GNU_versym`:
* yaml2obj: set `sh_link` to index of `.dynsym` section automatically.
For `SHT_GNU_verdef`:
* yaml2obj: set `sh_link` to index of `.dynstr` section automatically.
* yaml2obj: set `sh_info` field automatically.
* obj2yaml: don't dump the `Info` field when its value matches the number of version definitions.
For `SHT_GNU_verneed`:
* yaml2obj: set `sh_link` to index of `.dynstr` section automatically.
* yaml2obj: set `sh_info` field automatically.
* obj2yaml: don't dump the `Info` field when its value matches the number of version dependencies.
Also, simplifies few test cases.
Differential revision: https://reviews.llvm.org/D94956
Similar to D77853. Change ADRP to print the target address in hex, instead of the raw immediate.
The behavior is similar to GNU objdump but we also include `0x`.
Note: GNU objdump is not consistent whether or not to emit `0x` for different architectures. We try emitting 0x consistently for all targets.
```
GNU objdump: adrp x16, 10000000
Old llvm-objdump: adrp x16, #0
New llvm-objdump: adrp x16, 0x10000000
```
`adrp Xd, 0x...` assembles to a relocation referencing `*ABS*+0x10000` which is not intended. We need to use a linker or use yaml2obj.
The main test is `test/tools/llvm-objdump/ELF/AArch64/pcrel-address.yaml`
Differential Revision: https://reviews.llvm.org/D93241
This also teaches MachO writers/readers about the MachO cpu subtype,
beyond the minimal subtype reader support present at the moment.
This also defines a preprocessor macro to allow users to distinguish
__arm64__ from __arm64e__.
arm64e defaults to an "apple-a12" CPU, which supports v8.3a, allowing
pointer-authentication codegen.
It also currently defaults to ios14 and macos11.
Differential Revision: https://reviews.llvm.org/D87095
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
Imagine we have a YAML declaration of few sections: `foo1`, `<unnamed 2>`, `foo3`, `foo4`.
To put them into segment we can do (1*):
```
Sections:
- Section: foo1
- Section: foo4
```
or we can use (2*):
```
Sections:
- Section: foo1
- Section: foo3
- Section: foo4
```
or (3*) :
```
Sections:
- Section: foo1
## "(index 2)" here is a name that we automatically created for a unnamed section.
- Section: (index 2)
- Section: foo3
- Section: foo4
```
It looks really confusing that we don't have to list all of sections.
At first I've tried to make this rule stricter and report an error when there is a gap
(i.e. when a section is included into segment, but not listed explicitly).
This did not work perfect, because such approach conflicts with unnamed sections/fills (see (3*)).
This patch drops "Sections" key and introduces 2 keys instead: `FirstSec` and `LastSec`.
Both are optional.
Differential revision: https://reviews.llvm.org/D90458
This removes Inputs/libbogus11.a
Initially I've removed it in D90013, but had to restore it, because BB found this
test is using it.
I've updated the test to use YAMLs, added comment and one more possible error check.
Differential revision: https://reviews.llvm.org/D90312
Currently the test uses 14 precompiled binaries. With the functionality
implemented in D89949, it is possible to remove them and use YAMLs instead.
Differential revision: https://reviews.llvm.org/D90013
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
I recently came across a MachO with multiple sections of the same name but
different segments. We should emit the segment name alongside the section name
for MachO's.
Differential Revision: https://reviews.llvm.org/D87119
AMDGPU ISA isn't backwards compatible and hence -mcpu must always be specified during disassembly.
However, the AMDGPU target CPU is stored in e_flags in the ELF object.
This patch allows targets to implement CPU string detection, and also implements it for AMDGPU by looking at e_flags.
Reviewed By: scott.linder
Differential Revision: https://reviews.llvm.org/D84519
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
If the referenced symbol of a J[U]MP_SLOT is invalid (e.g. symbol index 0), llvm-objdump -d will bail out:
```
error: 'a': st_name (0x326600) is past the end of the string table of size 0x7
```
where 0x326600 is the st_name field of the first entry past the end of .symtab
Change it to a warning to continue dumping.
`X86/plt.test` uses a prebuilt executable, so I pick `ELF/AArch64/plt.test`
which has a YAML input and can be easily modified.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D85623
Add support for constant MachO::CPU_SUBTYPE_ARM64_V8. This constant is
needed so as to match `llvm-libtool-darwin`'s behavior to that of
cctools' libtool when `-arch_only` flag is passed in on command line.
Reviewed by jhenderson, alexshap, smeenai
Differential Revision: https://reviews.llvm.org/D85041
llvm-objdump currently calls report_fatal_error() when the e_phoff field is invalid.
This is tested by elf-invalid-phdr.test which has the following issues:
1) It uses a precompiled object.
2) it could be a part of invalid.test.
3) It tests the Object lib, but we have no separate test for llvm-objdump.
This patch addresses issues mentioned.
Differential revision: https://reviews.llvm.org/D83559
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
This patch extends D58439 (`llvm/test/{yaml2obj,obj2yaml}/**/*.yaml`) and runs all
`llvm/test/**/*.yaml`
Many directories have configured `.yaml` (see the deleted lit.local.cfg
files). Yet still some don't configure .yaml and have caused stale tests:
* 8c5825befb test/llvm-readobj
* bdc3134e23 test/ExecutionEngine
Just hoist .yaml to `llvm/test/lit.cfg.py`. Also delete .cxx which is
not used. The number of tests running on my machine increases from 38304 to 38309.
The list of new tests:
```
ExecutionEngine/RuntimeDyld/X86/ELF_x86-64_none.yaml
Object/archive-error-tmp.txt
tools/llvm-ar/coff-weak.yaml
tools/llvm-readobj/ELF/verneed-flags.yaml
tools/obj2yaml/COFF/bss.s
```
Reviewed By: grimar, jhenderson, rupprecht
Differential Revision: https://reviews.llvm.org/D83350
Place the instruction at the 24th column (0-based indexing), matching
GNU objdump ARM/AArch64/powerpc/etc when the address is low.
This is beneficial for non-x86 targets which have short instruction
lengths.
```
// GNU objdump AArch64
0: 91001062 add x2, x3, #0x4
400078: 91001062 add x2, x3, #0x4
// llvm-objdump, with this patch
0: 62 10 00 91 add x2, x3, #4
400078: 62 10 00 91 add x2, x3, #4
// llvm-objdump, if we change to print a word instead of bytes in the future
0: 91001062 add x2, x3, #4
400078: 91001062 add x2, x3, #4
// GNU objdump Thumb
0: bf00 nop
// GNU objdump Power ISA 3.1 64-bit instruction
// 0: 00 00 10 04 plwa r3,0
// 4: 00 00 60 a4
```
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D81590
SUMMARY:
when there are two symbol has the same address. llvm-objdump -D -symbol-description will select symbol based on the following rule:
1. using Label first if there is a Label symbol.
2. If there is not Label, using a symbol which has Storage Mapping class.
3. if more than one symbol has storage mapping class, put the TC0 has the low priority, for other storage mapping class , compare based on the value.
Reviewers: James Henderson ,hubert.reinterpretcast,
Differential Revision: https://reviews.llvm.org/D78387
Fangrui Song