24 Commits

Author SHA1 Message Date
quic-akaryaki
4070dffd34
[llvm-objcopy] Add --gap-fill and --pad-to options (#65815)
`--gap-fill <value>` fills the gaps between sections with a specified
8-bit value, instead of zero.
`--pad-to <address>` pads the output binary up to the specified load
address, using the 8-bit value from `--gap-fill` or zero.

These options are only supported for ELF input and binary output.
2023-12-14 16:28:34 -06:00
Kazu Hirata
586ecdf205
[llvm] Use StringRef::{starts,ends}_with (NFC) (#74956)
This patch replaces uses of StringRef::{starts,ends}with with
StringRef::{starts,ends}_with for consistency with
std::{string,string_view}::{starts,ends}_with in C++20.

I'm planning to deprecate and eventually remove
StringRef::{starts,ends}with.
2023-12-11 21:01:36 -08:00
Mikael Holmen
336b7a256b [ObjCopy] Fix warning in conditional expression [NFC]
Without the fix gcc warned with
 ../lib/ObjCopy/ELF/ELFObjcopy.cpp: In function 'uint64_t getSectionFlagsPreserveMask(uint64_t, uint64_t, uint16_t)':
 ../lib/ObjCopy/ELF/ELFObjcopy.cpp:106:31: warning: enumeral and non-enumeral type in conditional expression [-Wextra]
   106 |       ~(EMachine == EM_X86_64 ? ELF::SHF_X86_64_LARGE : 0UL);
       |         ~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2023-09-29 12:44:54 +02:00
Thomas Köppe
6f1395a1fe [llvm-objcopy] --set-section-flags: allow "large" to add SHF_X86_64_LARGE
Currently, objcopy cannot set the new flag SHF_X86_64_LARGE. This change introduces the named flag "large" which translates to that section flag.

An "invalid argument" error is produced if a user attempts to set the flag on an architecture other than X86_64.

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D153262
2023-07-25 09:47:02 -07:00
Thomas Köppe
b617669229 [llvm-objcopy] Remove unused internal helper function template makeStringError. NFC
Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D153671
2023-07-15 11:22:54 -07:00
Alexey Karyakin
c973123fdc [llvm-objcopy] -O binary: do not align physical addresses
llvm-objcopy should not insert padding before a section if its
physical addresses is not aligned to section's alignment. This
behavior will match GNU objcopy and is important for embedded images
where the physical address is used to store the initial data image.
The loader typically will copy this image using a start symbol
created by the linker. If llvm-objcopy inserts padding before such a
section, the symbol address will not match the location in the image.

This commit refines the change in https://reviews.llvm.org/D128961
which intended to align sections which type changed from NOBITS and
their offset may not be aligned. However, it affected all sections.

Fix https://github.com/llvm/llvm-project/issues/62636

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D150276
2023-06-20 15:45:33 -07:00
Krzysztof Parzyszek
ebc757d3b6 Revert "[llvm-objcopy] -O binary: do not align physical addresses"
This reverts commit eb1442d0f73c76cfb5051d133f858fe760d189cf.

The test tools/llvm-objcopy/ELF/binary-paddr.test fails on
ppc64be-clang-test-suite:
https://lab.llvm.org/buildbot#builders/231/builds/13120

Reverting at author's request.
2023-06-20 14:46:55 -07:00
Alexey Karyakin
eb1442d0f7 [llvm-objcopy] -O binary: do not align physical addresses
llvm-objcopy should not insert padding before a section if its
physical addresses is not aligned to section's alignment. This
behavior will match GNU objcopy and is important for embedded images
where the physical address is used to store the initial data image.
The loader typically will copy this image using a start symbol
created by the linker. If llvm-objcopy inserts padding before such a
section, the symbol address will not match the location in the image.

This commit refines the change in https://reviews.llvm.org/D128961
which intended to align sections which type changed from NOBITS and
their offset may not be aligned. However, it affected all sections.

Fix https://github.com/llvm/llvm-project/issues/62636

Reviewed By: jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D150276
2023-06-20 13:28:40 -07:00
Fangrui Song
67ba5c507a std::optional::value => operator*/operator->
value() has undesired exception checking semantics and calls
__throw_bad_optional_access in libc++. Moreover, the API is unavailable without
_LIBCPP_NO_EXCEPTIONS on older Mach-O platforms (see
_LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS).

This fixes check-llvm.
2022-12-17 01:42:39 +00:00
Fangrui Song
a996cc217c Remove unused #include "llvm/ADT/Optional.h" 2022-12-05 06:31:11 +00:00
Fangrui Song
c997fe6586 [llvm-objcopy] --compress-debug-sections: remove tail padding for ELFCLASS32
For an ELFCLASS32 object, a compressed section due to --compress-debug-sections={zlib,zstd} has a
tail padding of 12 zero bytes. zlib happily allows this while zstd is rigid and
reports `error: '{{.*}}': failed to decompress section '.debug_foo': Src size is incorrect`.

Cole Kissane reported the problem.

Reviewed By: jhenderson, phosek

Differential Revision: https://reviews.llvm.org/D134385
2022-09-22 10:26:47 -07:00
Kazu Hirata
611ffcf4e4 [llvm] Use value instead of getValue (NFC) 2022-07-13 23:11:56 -07:00
Fangrui Song
b28412d539 [llvm-objcopy][ELF] Add --set-section-type
The request is mentioned on D129053. I feel that having this functionality is
mildly useful (not strong).

* Rename .ctors to .init_array and change sh_type to SHT_INIT_ARRAY (GNU objcopy
  detects the special name but we don't).
* Craft tests for a new SHT_LLVM_* extension

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D129337
2022-07-13 10:04:21 -07:00
Fangrui Song
7c03b7d668 [llvm-objcopy][ELF] Allow --set-section-flags src=... and --rename-section src=tst
* GNU objcopy supports --set-section-flags src=... --rename-section src=tst and --set-section-flags runs first.
* GNU objcopy processes --update-section before --rename-section.

To match the two behaviors, postpone --rename-section and allow its use together
with --set-section-flags.

As a side effect, --rename-section=.foo1=.foo2 --add-section=.foo1=/dev/null
leads to .foo2 while GNU objcopy surprisingly produces .foo1 (so
--set-section-flags --add-section --rename-section do not form a total order).
I think the deviation is fine as a total order makes more sense.

Rename set-section-flags-and-rename.test to
set-section-attr-and-rename.test and additionally test --set-section-alignment

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D129336
2022-07-11 09:04:45 -07:00
Fangrui Song
45ae553109 [llvm-objcopy] Remove support for legacy .zdebug sections
clang 14 removed -gz=zlib-gnu support and ld.lld removed linker input support
for zlib-gnu in D126793. Now let's remove zlib-gnu from llvm-objcopy.

* .zdebug* sections are no longer recognized as debug sections. --strip* don't remove them.
  They are copied like other opaque sections
* --decompress-debug-sections does not uncompress .zdebug* sections
* --compress-debug-sections=zlib-gnu is not supported

It is very rare but in case a user has object files using .zdebug . They can use
llvm-objcopy<15 or GNU objcopy for uncompression.
--compress-debug-sections=zlib-gnu is unlikely ever used by anyone, so I do not
add a custom diagnostic.

Differential Revision: https://reviews.llvm.org/D128688
2022-06-29 10:42:55 -07:00
Kazu Hirata
a7938c74f1 [llvm] Don't use Optional::hasValue (NFC)
This patch replaces Optional::hasValue with the implicit cast to bool
in conditionals only.
2022-06-25 21:42:52 -07:00
Kazu Hirata
3b7c3a654c Revert "Don't use Optional::hasValue (NFC)"
This reverts commit aa8feeefd3ac6c78ee8f67bf033976fc7d68bc6d.
2022-06-25 11:56:50 -07:00
Kazu Hirata
aa8feeefd3 Don't use Optional::hasValue (NFC) 2022-06-25 11:55:57 -07:00
Kazu Hirata
129b531c9c [llvm] Use value_or instead of getValueOr (NFC) 2022-06-18 23:07:11 -07:00
Fangrui Song
30718f3aa6 [llvm-objcopy] --weaken-symbol/--weaken: weaken STB_GNU_UNIQUE symbols
STB_GNU_UNIQUE is like STB_GLOBAL with extra semantics:

* gold and ld.lld: changed to STB_GLOBAL if --no-gnu-unique is specified
* glibc: unique even with dlopen `RTLD_LOCAL`, implies DF_1_NODELETE

Therefore, I think it makes sense for --weaken-symbol/--weaken-symbols/--weaken
to change STB_GNU_UNIQUE symbols.

binutils 2.39 will have the same behavior: https://sourceware.org/bugzilla/show_bug.cgi?id=28926

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D120638
2022-03-16 09:48:19 -07:00
Fangrui Song
cce3521020 [llvm-objcopy] Simplify CompressedSection creation. NFC
Remove Expected<CompressedSection> factory functions in favor of constructors
now that zlib::compress returns void (D121512).

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D121644
2022-03-14 23:15:15 -07:00
Alexey Lapshin
a6f3fedc3f [objcopy] Refactor CommonConfig to add posibility to specify added/updated sections as MemoryBuffer.
Current objcopy implementation has a possibility to add or update sections.
The incoming section is specified as a pair: section name and name of the file
containing section data. The interface does not allow to specify incoming
section as a memory buffer. This patch adds possibility to specify incoming
section as a memory buffer.

Differential Revision: https://reviews.llvm.org/D120486
2022-03-01 14:49:41 +03:00
Alexey Lapshin
25d7b4fb44 [objcopy][NFC] Rename files to avoid clashing of archive members.
libtool uses file names to name members of an static library.
Files, located in different directories and having matching name,
would have the same name inside an archive. This is not a problem
for ld, but may be a problem for ar. This patch renames files
from ObjCopy library to avoid names clashing.

See https://reviews.llvm.org/D88827#3335814

Differential Revision: https://reviews.llvm.org/D120345
2022-02-23 13:05:39 +03:00
Alexey Lapshin
f75da0c8e6 [llvm-objcopy][NFC] Move core implementation of llvm-objcopy into separate library.
This patch moves core implementation of llvm-objcopy into Object library
(http://lists.llvm.org/pipermail/llvm-dev/2020-September/145075.html).
The functionality for parsing input options is left inside tools/llvm-objcopy.
The interface of ObjCopy library:

ObjCopy/ELF/ELFObjcopy.h

```
Error executeObjcopyOnIHex(const CopyConfig &Config, MemoryBuffer &In,
                           Buffer &Out);
Error executeObjcopyOnRawBinary(const CopyConfig &Config, MemoryBuffer &In,
                                Buffer &Out);
Error executeObjcopyOnBinary(const CopyConfig &Config,
                             object::ELFObjectFileBase &In, Buffer &Out);

```
ObjCopy/COFF/COFFObjcopy.h

```
Error executeObjcopyOnBinary(const CopyConfig &Config,
                             object::COFFObjectFile &In, Buffer &Out);

```
ObjCopy/MachO/MachOObjcopy.h

```
Error executeObjcopyOnBinary(const CopyConfig &Config,
                             object::MachOObjectFile &In, Buffer &Out);

```
ObjCopy/wasm/WasmObjcopy.h

```
Error executeObjcopyOnBinary(const CopyConfig &Config,
                             object::WasmObjectFile &In, Buffer &Out);

```

Differential Revision: https://reviews.llvm.org/D88827
2022-02-17 13:11:42 +03:00