Commit Graph

19 Commits

Author SHA1 Message Date
George Rimar
4f51fe0c01 [llvm-objcopy] - Remove dead code. NFCI.
DecompressedSection can only be created if --decompress-debug-sections is specified.
https://github.com/llvm-mirror/llvm/blob/master/tools/llvm-objcopy/ELF/ELFObjcopy.cpp#L492

If it is specified when !zlib::isAvailable(), we error out early when parsing the options:
https://github.com/llvm-mirror/llvm/blob/master/tools/llvm-objcopy/CopyConfig.cpp#L657

What means the code I am removing in this patch is dead.

Differential revision: https://reviews.llvm.org/D59017

llvm-svn: 355505
2019-03-06 14:12:18 +00:00
George Rimar
edd70802af [llvm-objcopy] - Remove an excessive zlib::isAvailable() check and dead code.
There are 2 places where llvm-objcopy creates CompressedSection:

For --compress-debug-sections. It might create the compressed section from
regular here:
https://github.com/llvm-mirror/llvm/blob/master/tools/llvm-objcopy/ELF/ELFObjcopy.cpp#L486

All initially compressed sections are created as CompressedSection during reading the sections
from an object:
https://github.com/llvm-mirror/llvm/blob/master/tools/llvm-objcopy/ELF/Object.cpp#L1118
Those have DebugCompressionType::None type and a different constructor.

Case 1 has the following code in its constructor:

if (!zlib::isAvailable()) {
  CompressionType = DebugCompressionType::None;
  return;
}
(https://github.com/llvm-mirror/llvm/blob/master/tools/llvm-objcopy/ELF/Object.cpp#L267)

We can never reach that code with because would report an error much earlier:
https://github.com/llvm-mirror/llvm/blob/master/tools/llvm-objcopy/CopyConfig.cpp#L480

So the code I am removing is dead. Landing this will address the issue mentioned in https://bugs.llvm.org/show_bug.cgi?id=40886.

Differential revision: https://reviews.llvm.org/D59019

llvm-svn: 355503
2019-03-06 14:08:27 +00:00
George Rimar
09f6aceae8 [llvm-objcopy] - Fix incorrect CompressedSection creation.
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
2019-03-06 14:01:54 +00:00
George Rimar
47c7c0875f [llvm-objdump] - Improve the error message for "removing a section that is used by relocation" case.
This refines/improves the error message introduced in D58625

Differential revision: https://reviews.llvm.org/D58709

llvm-svn: 355074
2019-02-28 08:21:50 +00:00
George Rimar
25f42156b9 [llvm-objcopy] - Check for invalidated relocations when removing a section.
This is https://bugs.llvm.org/show_bug.cgi?id=40818

Removing a section that is used by relocation is an error
we did not report. The patch fixes that.

Differential revision: https://reviews.llvm.org/D58625

llvm-svn: 354962
2019-02-27 11:18:27 +00:00
Jordan Rupprecht
d23e0bcdb9 [llvm-objcopy] Make removeSectionReferences batched
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
2019-02-21 16:45:42 +00:00
Jordan Rupprecht
949f2902d0 [llvm-objcopy][NFC] Propagate errors in removeSymbols/removeSectionReferences
Reviewers: jhenderson, alexshap, jakehehrlich, espindola

Reviewed By: jhenderson

Subscribers: emaste, arichardson, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57543

llvm-svn: 352877
2019-02-01 15:20:36 +00:00
Jordan Rupprecht
465c087d4f [llvm-objcopy] Return Error from Buffer::allocate(), [ELF]Writer::finalize(), and [ELF]Writer::commit()
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
2019-01-22 23:49:16 +00:00
Chandler Carruth
ae65e281f3 Update the file headers across all of the LLVM projects in the monorepo
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
2019-01-19 08:50:56 +00:00
Jordan Rupprecht
8c45d7e2bc [llvm-objcopy] Fix buildbots on older compilers
llvm-svn: 350343
2019-01-03 19:09:00 +00:00
Jordan Rupprecht
e3af1289c6 Fix typos in comments
llvm-svn: 350337
2019-01-03 17:51:32 +00:00
Jordan Rupprecht
b181c20ca2 [llvm-objcopy][ELF] Implement a mutable section visitor that updates size-related fields (Size, EntrySize, Align) before layout.
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
2019-01-03 17:45:30 +00:00
George Rimar
95f4183d9d [llvm-objcopy] Use ELFOSABI_NONE instead of 0. NFC.
This was requested during the review of D55886.
(sorry, forgot to address this)

llvm-svn: 349741
2018-12-20 10:59:52 +00:00
George Rimar
284bbb15a7 [llvm-objcopy] - Do not drop the OS/ABI and ABIVersion fields of ELF header
This is https://bugs.llvm.org/show_bug.cgi?id=40005,

Patch teaches llvm-objcopy to preserve OS/ABI and ABIVersion fields of ELF header.
(Currently, it drops them to zero).

Differential revision: https://reviews.llvm.org/D55886

llvm-svn: 349738
2018-12-20 10:51:42 +00:00
Fangrui Song
cb3e0aa543 Use llvm::copy. NFC
llvm-svn: 347126
2018-11-17 01:44:25 +00:00
Fangrui Song
8d22f81dc4 [llvm-objcopy] Use llvm::all_of and rename the variables "Segment" to avoid confusion with the type of the same name
llvm-svn: 347123
2018-11-17 01:15:55 +00:00
Jordan Rupprecht
f78bbcd84a [llvm-objcopy] Don't apply --localize flags to common symbols
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
2018-11-01 17:26:36 +00:00
Fangrui Song
775a75a648 [llvm-objcopy] Use proper cases
Reviewers: jhenderson, alexshap, jakehehrlich, espindola, rupprecht

Reviewed By: jhenderson, rupprecht

Subscribers: emaste, arichardson, rupprecht, llvm-commits

Differential Revision: https://reviews.llvm.org/D53971

llvm-svn: 345845
2018-11-01 16:02:12 +00:00
Alexander Shaposhnikov
20fb81927b [llvm-objcopy] Move elf-specific code into subfolder
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
2018-10-29 21:22:58 +00:00