When we do debug printing of atoms, they expect their parent file
to have an ordinal. Right now we trigger a bunch of asserts.
This doesn't actually manifest in differences in any real tests, but
even if the only thing it does is improve debuggability then its still
useful.
llvm-svn: 259450
Instead of leave unused fields as is, set them to nullptr.
Currnetly this is NFC, but if you call writeResults more than
once, you should be able to see the difference.
llvm-svn: 259444
The ObjCPass is going to need to create pointer sized relocations in
the ObjC sections. This method will be used to give us a target independent
way of getting the correct kind for the refererence.
llvm-svn: 259441
An upcoming patch will use this to create lists of ObjC methods.
Adding it now to reduce the amount of code in that patch.
Test cases will follow in the other patch too.
llvm-svn: 259440
This adds the no_objc_category_merging cmdline option which will
be used in an upcoming commit to disable the category optimizer.
It is on by default in ld64 so we match that here.
Test case will come soon with the patch to make use of this option.
llvm-svn: 259439
Most of the other methods to access Reference's were on DefinedAtom so
this just keeps them all together.
This will be used in a future patch in ObjCPass which needs to add
new references. The method is virtual because we may add references to
different data structures depending on whether we parsed a macho file or
yaml.
llvm-svn: 259436
This will be used by a future commit which wanted to compare iterators
for equality.
Also changed operator!= to be in terms of the new operator==
llvm-svn: 259431
When we parse a MachoFile, we set a number of members from the parsed
file, for example, subsectionsViaSymbols.
However, a number of passes, such as ObjCPass, create local copies of
MachoFile and don't get the benefit of setting flags and other fields in
the parser. Instead we can just give a more sensible default as the parser
will definitely get the correct value from the file anyway.
llvm-svn: 259426
Now that MachoFile has classof(), we can use dyn_cast instead which
is actually the only safe way to handle this.
Turns out this actually manifests as a bug as we were incorrectly
casting instances which weren't MachoFile in to a MachoFile.
Unfortunately, there's no reliable way of checking for this as it
requires that the file we are looking for has a 0 at exactly the byte
we need for the load of subsectionsViaSymbols.
llvm-svn: 259413
Previously, the methods to get symbol addresses were somewhat scattered
in many places. You can use getEntryAddr returns the address of the symbol,
but if you want to get the GOT address for the symbol, you needed to call
Out<ELFT>::Got->getEntryAddr(Sym). This change adds new functions, getVA,
getGotVA, getGotPltVA, and getPltVA to SymbolBody, so that you can use
SymbolBody as the central place to ask about symbols.
http://reviews.llvm.org/D16710
llvm-svn: 259404
__DATA, __objc_catlist contains a list of pointers to categories.
We want to atomize it so that the ObjC pass can later optimize and remove
categories. That will be a later patch.
llvm-svn: 259386
This avoids the need to have reserve and addString in sync.
We avoid hashing the global symbols again. This means that we don't
merge a global symbol that has the same name as some other string, but
that doesn't seem very common. The string table size is the same in
clang an scylladb with or without hashing global symbols again.
llvm-svn: 259136
This function is a predicate that a given relocation can be relaxed.
The previous name implied that it returns true if a given relocation
has already been optimized away.
llvm-svn: 259128
In many situations, we don't want to exit at the first error even in the
process model. For example, it is better to report all undefined symbols
rather than reporting the first one that the linker picked up randomly.
In order to handle such errors, we don't need to wrap everything with
ErrorOr (thanks for David Blaikie for pointing this out!) Instead, we
can set a flag to record the fact that we found an error and keep it
going until it reaches a reasonable checkpoint.
This idea should be applicable to other places. For example, we can
ignore broken relocations and check for errors after visiting all relocs.
In this patch, I rename error to fatal, and introduce another version of
error which doesn't call exit. That function instead sets HasError to true.
Once HasError becomes true, it stays true, so that we know that there
was an error if it is true.
I think introducing a non-noreturn error reporting function is by itself
a good idea, and it looks to me that this also provides a gradual path
towards lld-as-a-library (or at least embed-lld-to-your-program) without
sacrificing code readability with lots of ErrorOr's.
http://reviews.llvm.org/D16641
llvm-svn: 259069
This does not solve the problem that we call isGnuIFunc function
both from RelocationSection and from the Writer::scanRelocs, but
this at least should improve readability. I'm taking an incremental
approach to reduce complexity.
llvm-svn: 258753
The TrieNode/TrieEdge data structures here are allocated in a bumpptrallocator.
Unfortunately, TrieNode contained a std::list<TrieEdge> and as the allocator doesn't
call the TrieNode destructor, we ended up leaking the memory allocated by the std::list
itself.
Instead we can use an intrusive list as then we save the extra allocations anyway.
llvm-svn: 258725
There are a few cases where we have almost duplicated code.
This patches fixes the simplest: the finalize and write of dynamic
section. Right now they have to have exactly the same structure to
decide if a DT_* entry is needed and then to actually write it.
We cannot just write it to a std::vector in the first pass since
addresses have not been computed yet.
llvm-svn: 258723
Main executable did not export symbols that exist both in the main executable and in DSOs before this patch.
Symbols from object files that override symbols in DSO should be added to .dynsym table.
Differential revision: http://reviews.llvm.org/D16405
llvm-svn: 258672
Summary: It looks like this snuck through in r256143/D15383.
Reviewers: ruiu, grimar
Differential Revision: http://reviews.llvm.org/D16500
llvm-svn: 258599
There was an off by one error because the StringRef.substr functions
second argument is a length, not the end index.
Also updated a few ELF files which failed when run on Jenkins with paths
including the @ character. This is often used in Jenkins for shared
workspace plugin.
Reviewed by Rui Ueyama
llvm-svn: 258583
This option matches the behaviour of ld64, that is it prevents globals
from being dead stripped in executables and dylibs.
Reviewed by Lang Hames
Differential Revision: http://reviews.llvm.org/D16026
llvm-svn: 258554
In InputSection.cpp it was possible to dereference null.
Had to change signature of relocateTlsOptimize to accept pointer instead of reference.
Differential revision: http://reviews.llvm.org/D16466
llvm-svn: 258508
In this code, we avoid calling needsCopyRel in writeTo because
we called that function already in scanRelocs. Making the same
decision twice is a waste and has a risk of a bug that we get
inconsistent resuts.
llvm-svn: 258430
Code for handling TLS relocations was moved out scanRelocs() to new function handleTlsRelocations().
That is because scanRelocs already too large to put more TLS code into it.
Differential revision: http://reviews.llvm.org/D16354
llvm-svn: 258392
Some MIPS relocation (for now R_MIPS_GOT16) requires creation of GOT
entries for symbol not included in the dynamic symbol table. They are
local symbols and non-local symbols with 'local' visibility. Local GOT
entries occupy continuous block between GOT header and regular GOT
entries.
The patch adds initial support for handling local GOT entries. The main
problem is allocating local GOT entries for local symbols. Such entries
should be initialized by high 16-bit of the symbol value. In ideal world
there should be no duplicated entries with the same values. But at the
moment of the `Writer::scanRelocs` call we do not know a value of the
symbol. In this patch we create new local GOT entry for each relocation
against local symbol, though we can exhaust GOT quickly. That needs to
be optimized later. When we calculate relocation we know a final symbol
value and request local GOT entry index. To do that we maintain map
between addresses and local GOT entry indexes. If we start to calculate
relocations in parallel we will have to serialize access to this map.
Differential Revision: http://reviews.llvm.org/D16324
llvm-svn: 258388
This pass currently emits an objc image info section if one is required.
This section contains the aggregated version and flags for all of the input
files.
llvm-svn: 258197
Like arch, os, etc, when we know we are going to use a file, we check
that the file has compatible objc constraints to the context, throw
appropriate errors where that is not the case, and hopefully set the
objc constraints on the context for use later.
Added 2 tests to ensure that we don't have incompatibilities between
host and simulator code as both will get x86 based architectures.
llvm-svn: 258173
Image info flags describe the objc constraint which is GC/retain/release/etc.
These need to be parsed and stored in the file so that we can do error checking.
That will come in a later commit.
llvm-svn: 258160
When generating a relocatable file, its only valid to set this flag if
all of the inputs also had the flag. Otherwise we may atomize incorrectly
when we link the relocatable file again.
Reviewed by Lang Hames.
Differential Revision: http://reviews.llvm.org/D16018
llvm-svn: 257976
The image info struct contains flags for what kind of GC/retain/release is required.
Give an error if we parse GC flags as these are unsupported.
llvm-svn: 257974
This file was failing to build with asan enabled. The reason being that
applyFixupFinal was writing 4-bytes worth of fixup in to an atom only
a single byte in length.
The test case didn't actually need this particular reloc so i've removed
it, although i'll follow up with future commits to actually verify that
relocs are to an address with enough space for the fixup to be applied.
llvm-svn: 257906
Added check for terminator CIE/FDE which has zero data size.
void EHOutputSection<ELFT>::addSectionAux(
...
// If CIE/FDE data length is zero then Length is 4, this
// shall be considered a terminator and processing shall end.
if (Length == 4)
break;
...
After this "Bug 25923 - lld/ELF2 linked application crashes if exceptions were used." is fixed for me. Self link of clang also works.
Initial commit message:
[ELF] - implemented --eh-frame-hdr command line option.
--eh-frame-hdr
Request creation of ".eh_frame_hdr" section and ELF "PT_GNU_EH_FRAME" segment header.
Both gold and the GNU linker support an option --eh-frame-hdr which tell them to construct a header for all the .eh_frame sections. This header is placed in a section named .eh_frame_hdr and also in a PT_GNU_EH_FRAME segment. At runtime the unwinder can find all the PT_GNU_EH_FRAME segments by calling dl_iterate_phdr.
This section contains a lookup table for quick binary search of FDEs.
Detailed info can be found here:
http://www.airs.com/blog/archives/462
Differential revision: http://reviews.llvm.org/D15712
llvm-svn: 257889
Rui Ueyama