Without this, sectionWithinSegment() will return the wrong answer for bss
sections. This doesn't seem to matter now (for non-broken ELF files), but
it will matter with a change that I'm working on.
Differential Revision: https://reviews.llvm.org/D58426
llvm-svn: 361578
The code in ELF/Object.cpp is sometimes a bit hard to read because of
lots of auto used everywhere. The main intention of this patch is
to replace them with the real type for places where it is not obvious.
Also it cleanups few places.
It is NFC change, but I want to be sure that there is no objections to do that since it
is massive.
DIfferential revision: https://reviews.llvm.org/D62260
llvm-svn: 361466
This patch brings various error messages into line with each other, by
removing trailing full stops, and making the first letter lower-case.
This addresses https://bugs.llvm.org/show_bug.cgi?id=40859.
Reviewed by: jhenderson, rupprecht, jakehehrlich
Differential Revision: https://reviews.llvm.org/D62072
Patch by Alex Brachet
llvm-svn: 361384
.gnu_debuglink section contains information regarding file with
debugging symbols, identified by its CRC32. This target file is not
intended to ever change or it would invalidate the stored checksum, yet
the checksum is calculated over and over again for each of the objects
inside the archive, usually hundreds of times.
This patch precomputes the CRC32 of the target once and then reuses the
value where required, saving lots of redundant I/O.
The error message reported should stay the same, although now it might
be reported earlier.
Reviewed by: jhenderson, jakehehrlich, MaskRay
Differential Revision: https://reviews.llvm.org/D61343
Patch by Michal Janiszewski
llvm-svn: 360661
This is a fix for https://bugs.llvm.org/show_bug.cgi?id=41775,
Problem is in the final line:
Size += this->EntrySize;
I checked that we do not actually need it in this place,
since we always call removeSectionReferences which
calls removeSymbols which updates the Size.
But it worth to keep it, that allows to relax the dependencies.
Differential revision: https://reviews.llvm.org/D61636
llvm-svn: 360227
This is a fix for https://bugs.llvm.org/show_bug.cgi?id=41371.
Currently, it is possible to break the sh_link field of the dynamic relocation section
by removing the section it refers to. The patch fixes an issue and adds 2 test cases.
One of them shows that it does not seem possible to break the sh_info field.
I added an assert to verify this.
Differential revision: https://reviews.llvm.org/D60825
llvm-svn: 359552
llvm-objcopy currently emits an error if a section to be removed is
referenced by another section. This is a reasonable thing to do, but is
different to GNU objcopy. We should allow users who know what they are
doing to have a way to produce the invalid ELF. This change adds a new
switch --allow-broken-links to both llvm-strip and llvm-objcopy to do
precisely that. The corresponding sh_link field is then set to 0 instead
of an error being emitted.
I cannot use llvm-readelf/readobj to test the link fields because they
emit an error if any sections, like the .dynsym, cannot be properly
loaded.
Reviewed by: rupprecht, grimar
Differential Revision: https://reviews.llvm.org/D60324
llvm-svn: 358649
This patch fixes https://bugs.llvm.org/show_bug.cgi?id=41293 and
https://bugs.llvm.org/show_bug.cgi?id=41045. llvm-objcopy assumed that
it could always read a section header string table. This isn't the case
when the sections were previously all stripped, and the e_shstrndx field
was set to 0. This patch fixes this. It also fixes a double space in an
error message relating to this issue, and prevents llvm-objcopy from
adding extra space for non-existent section headers, meaning that
--strip-sections on the output of a previous --strip-sections run
produces identical output, simplifying the test.
Reviewed by: rupprecht, grimar
Differential Revision: https://reviews.llvm.org/D59989
llvm-svn: 357475
Summary:
BTW, STLExtras.h provides llvm::size() which is similar to std::size()
for random access iterators. However, if we prefer qualified
llvm::size(), the member function .size() will be more convenient.
Reviewers: jhenderson, jakehehrlich, rupprecht, grimar, alexshap, espindola
Reviewed By: grimar
Subscribers: emaste, arichardson, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60028
llvm-svn: 357347
llvm-objcopy previously knew nothing about data in segments that wasn't
covered by section headers, meaning that it wrote zeroes instead of what
was there. As it is possible for this data to be useful to the loader,
this patch causes llvm-objcopy to start preserving this data. Data in
sections that are explicitly removed continues to be written as zeroes.
This fixes https://bugs.llvm.org/show_bug.cgi?id=41005.
Reviewed by: jakehehrlich, rupprecht
Differential Revision: https://reviews.llvm.org/D59483
llvm-svn: 356919
Fix: r356853 + set AddressAlign to 4 in
Inputs/compress-debug-sections.yaml for the new group section introduced.
Original commit message:
Currently, llvm-objcopy incorrectly handles compression and decompression of the
sections from COMDAT groups, because we do not implement the
replaceSectionReferences for this type of the sections.
The patch does that.
Differential revision: https://reviews.llvm.org/D59638
llvm-svn: 356856
This patch fixes the reason of ubsan failure (UB detected)
happened after landing the D59638 (I had to revert it).
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap-ubsan/builds/11760/steps/check-llvm%20ubsan/logs/stdio)
Problem is the following. Our implementation of GroupSection assumes that
its address is 4 bytes aligned when writes it:
template <class ELFT>
void ELFSectionWriter<ELFT>::visit(const GroupSection &Sec) {
ELF::Elf32_Word *Buf =
reinterpret_cast<ELF::Elf32_Word *>(Out.getBufferStart() + Sec.Offset);
...
But the test case for D59638 did not set AddressAlign in YAML. So address was
not 4 bytes aligned since Sec.Offset was odd. That triggered the issue.
This patch teaches llvm-objcopy to report an error for such sections (which should
not met in reality), what is better than having UB.
Differential revision: https://reviews.llvm.org/D59695
llvm-svn: 356853
Currently, llvm-objcopy incorrectly handles compression and decompression of the
sections from COMDAT groups, because we do not implement the
replaceSectionReferences for this type of the sections.
The patch does that.
Differential revision: https://reviews.llvm.org/D59638
llvm-svn: 356738
If the compression was used and we had a symbol not involved in relocation,
we never updated its section and it was silently removed from the output.
Differential revision: https://reviews.llvm.org/D59542
llvm-svn: 356554
This fixes the https://bugs.llvm.org/show_bug.cgi?id=40980.
Previously if string optimization occurred as a result of
StringTableBuilder's finalize() method, the size wasn't updated.
This hopefully also makes the interaction between sections during finalization
processes a bit more clear.
Differential revision: https://reviews.llvm.org/D59488
llvm-svn: 356371
When --compress-debug-sections is given,
llvm-objcopy removes the uncompressed sections and adds compressed to the section list.
This makes all the pointers to old sections to be outdated.
Currently, code already has logic for replacing the target sections of the relocation
sections. But we also have to update the relocations by themselves.
This fixes https://bugs.llvm.org/show_bug.cgi?id=40885.
Differential revision: https://reviews.llvm.org/D58960
llvm-svn: 355821
We should create CompressedSection only if the section has SHF_COMPRESSED flag
or it's name starts from '.zdebug'.
Currently, we create it if section's data starts from ZLIB signature.
Differential revision: https://reviews.llvm.org/D59018
llvm-svn: 355501
Summary:
Removing a large number of sections from a file with a lot of symbols can have abysmal (i.e. O(n^2)) performance, e.g. when running `--only-section` to extract one section out of a large file.
This comes from iterating over all symbols in the symbol table each time we remove a section, to remove references to the section we just removed.
Instead, do just one pass of symbol removal by passing a hash set of all the sections we'd like to remove references to.
This fixes a regression when running llvm-objcopy -j <one section> on an object file with many sections and symbols -- on my machine, running `objcopy -j .keep_me huge-input.o /tmp/foo.o` takes .3s with GNU objcopy, 1.3s with an updated llvm-objcopy, and 7+ minutes with llvm-objcopy prior to this patch.
Reviewers: MaskRay, jhenderson, jakehehrlich, alexshap, espindola
Reviewed By: MaskRay, jhenderson
Subscribers: echristo, emaste, arichardson, mgrang, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58296
llvm-svn: 354597
Summary:
This patch changes a few methods to return Error instead of manually calling error/reportError to abort. This will make it easier to extract into a library.
Note that error() takes just a string (this patch also adds an overload that takes an Error), while reportError() takes string + [error/code]. To help unify things, use FileError to associate a given filename with an error. Note that this takes some special care (for now), e.g. calling reportError(FileName, <something that could be FileError>) will duplicate the filename. The goal is to eventually remove reportError() and have every error associated with a file to be a FileError, and just one error handling block at the tool level.
This change was suggested in D56806. I took it a little further than suggested, but completely fixing llvm-objcopy will take a couple more patches. If this approach looks good, I'll commit this and apply similar patche(s) for the rest.
This change is NFC in terms of non-error related code, although the error message changes in one context.
Reviewers: alexshap, jhenderson, jakehehrlich, mstorsjo, espindola
Reviewed By: alexshap, jhenderson
Subscribers: llvm-commits, emaste, arichardson
Differential Revision: https://reviews.llvm.org/D56930
llvm-svn: 351896
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
Fix EntrySize, Size, and Align before doing layout calculation.
As a side cleanup, this removes a dependence on sizeof(Elf_Sym) within BinaryReader, so we can untemplatize that.
This unblocks a cleaner implementation of handling the -O<format> flag. See D53667 for a previous attempt. Actual implementation of the -O<format> flag will come in an upcoming commit, this is largely a NFC (although not _totally_ one, because alignment on binary input was actually wrong before).
Reviewers: jakehehrlich, jhenderson, alexshap, espindola
Reviewed By: jhenderson
Subscribers: emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D56211
llvm-svn: 350336
Summary:
--localize-symbol and --localize-hidden will currently localize common symbols. GNU objcopy will not localize these symbols even when explicitly requested, which seems reasonable; common symbols should always be global so they can be merged during linking.
See PR39461
Reviewers: jakehehrlich, jhenderson, alexshap, MaskRay, espindola
Reviewed By: jakehehrlich, jhenderson, alexshap, MaskRay
Subscribers: emaste, arichardson, alexshap, MaskRay, llvm-commits
Differential Revision: https://reviews.llvm.org/D53782
llvm-svn: 345856
In this diff the elf-specific code is moved into the subfolder ELF
(and factored out from llvm-objcopy.cpp).
Test plan: make check-all
Differential revision: https://reviews.llvm.org/D53790
llvm-svn: 345544
Eugene Leviant