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This makes all the pointers to old sections to be outdated.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