This test didn't actually test the functionality. The new test
verifies that "-verify" is passed if and only if -disable-verify
is not given.
llvm-svn: 265316
Note, this is https://llvm.org/bugs/show_bug.cgi?id=27187.
The problem here was that just converting an error to a bool doesn't
always set the checked bit. We only set that bit if the Error didn't
actually contain an error. Otherwise we'd end potentially up silently
dropping it.
Instead just use the consumeError method which is designed to allow us
to drop an error.
llvm-svn: 265311
The only way to get an object file with symbols marked by the STO_MIPS_PIC
flag is to link PIC and non-PIC object files and generate a relocatable
output using '-r' command line option. Now LLD is able to generate a relocatable
output but does not mark PIC symbols by the STO_MIPS_PIC flag. So I have
to use binary input mips-sto-pic.o generated by GNU BFD linker.
llvm-svn: 265310
Our symbol representation was redundant, and some times would get out of
sync. It had an Elf_Sym, but some fields were copied to SymbolBody.
Different parts of the code were checking the bits in SymbolBody and
others were checking Elf_Sym.
There are two general approaches to fix this:
* Copy the required information and don't store and Elf_Sym.
* Don't copy the information and always use the Elf_Smy.
The second way sounds tempting, but has a big problem: we would have to
template SymbolBody. I started doing it, but it requires templeting
*everything* and creates a bit chicken and egg problem at the driver
where we have to find ELFT before we can create an ArchiveFile for
example.
As much as possible I compared the test differences with what gold and
bfd produce to make sure they are still valid. In most cases we are just
adding hidden visibility to a local symbol, which is harmless.
In most tests this is a small speedup. The only slowdown was scylla
(1.006X). The largest speedup was clang with no --build-id, -O3 or
--gc-sections (i.e.: focus on the relocations): 1.019X.
llvm-svn: 265293
So, there are some cases when the IR Linker produces a broken
module (which doesn't pass the verifier) and we end up asserting
inside the verifier. I think it's always a bug producing a module
which does not pass the verifier but there are some cases in which
people can live with the broken module (e.g. if only DebugInfo
metadata are broken). The gold plugin has something similar.
This commit is motivated by a situation I found in the
wild. It seems that somebody else discovered it independently
and reported in PR24923.
llvm-svn: 265258
We already got this right, but it never hurts adding another
test, in case we'll change the handling in the future, to ensure
we don't break it.
llvm-svn: 265256
Currently we create a file called .lto.bc. In UNIX,
ls(1) by default doesn't show up files starting with
a dot, as they're (only by convention) hidden.
This makes the output of -save-temps a little bit
hard to find. Use "a.out.lto.bc" instead if the
output file is not specified.
While here, change an existing -save-temps test to
exercise this more interesting behaviour.
llvm-svn: 265254
GNU ld seems to write a PT_INTERP header into executables containing a
default (read: bogus) value if --dynamic-linker flag is not provided.
LLD is different in the sense that it omits it unless --dynamic-linker
is provided, which seems fair.
Binutils 2.26 added a new flag, --no-dynamic-linker, that can be used to
generate binaries without PT_INTERP. Let's go ahead and also add this
flag to LLD, so that we can invoke the linker in a portable way.
Reviewed by: ruiu
Differential Revision: http://reviews.llvm.org/D18723
llvm-svn: 265246
DefinedElf was a superclass of DefinedRegular and SharedSymbol classes
and represented the notion of defined symbols created for ELF symbols.
It turned out that we didn't use that class often. We had only two
occurrences of dyn_cast'ing to DefinedElf, and both were easily
rewritten without it.
The class was also a bit confusing. The concept of "created for ELF
symbol" is orthogonal to defined/undefined types. However, we had
two distinct classes, DefinedElf and UndefinedElf.
This patch simply removes the class. Now the class hierarchy is one
level shallower.
llvm-svn: 265234
If a symbol is defined in an archive, when we replace its body
the isUsedInRegularObj wasn't set correctly. Internalize makes
its decision based on that bit so we ended up internalizing
symbols that we shouldn't (because they're referenced).
This should fix. Thanks to Peter and Rafael for discussion
and help diagnosing the issue!
Found during LTO of unittests.
llvm-svn: 265208
c:\b\slave\sanitizer-windows\llvm\tools\lld\elf\Config.h(94) : error C2797: 'lld:🧝:Configuration::MLlvm': list initialization inside member initializer list or non-static data member initializer is not implemented
llvm-svn: 265207
Extracts code for initializing dummies sections
to avoid possible duplication in following patches.
Differential review: http://reviews.llvm.org/D18691
llvm-svn: 265159
Some functions in Writer reports error using HasError, and some reports
their return values. This patch makes them to consistently use HasError.
llvm-svn: 265156
fixAbsoluteSymbols fixes linker-created symbol addresses. Since we don't
create such symbols for relocatable output, we don't need to call this
function.
llvm-svn: 265154
assignAddressesRelocatable function did not set addresses to sections
despite its name. What it actually did is to set file offsets to sections.
assignAddresses function assigned addresses and file offsets to sections.
So there was a confusion what they were doing, and they had duplicate code.
This patch separates file offset assignments from address assignments.
A new function, assignFileOffsets assign file offsets. assignAddresses
do not care about file offsets anymore.
llvm-svn: 265151
The extra fix is to note that it still requires copy relocations.
Original message:
Change how we handle R_MIPS_LO16.
Mips aligns PT_LOAD to 16 bits (0x10000). That means that the lower 16
bits are always the same, so we can, effectively, say that the
relocation is relative.
P.S.: Suggestions for a better name for the predicate are welcome :-)
llvm-svn: 265150
That is consistent with other symbols: _edata, _etext
and can help to avoid duplicate code.
Differential revision: http://reviews.llvm.org/D18655
llvm-svn: 265129
This fixes bootstrap of llvm-tblgen (with LTO) and PR27150.
Slightly longer explanation follows.
Emission of .init_array instead of .ctors is supported only on a
subset of the Target LLVM supports. Codegen needs to be conservative
and always emit .ctors unless instructed otherwise (based on target).
If the dynamic linker sees .init_array it completely ignores
what's inside .ctors and therefore some constructors are not called
(and this causes llvm-tblgen to crash on startup).
Teach LLD/LTO about the Codegen options so we end up always emitting
.init_array and avoid this issue.
In future, we might end up supporting mix of .ctors and .init_array
in different input files if this shows up as a real-world use case.
The way gold handles this case is mapping .ctors from input into
.init_array in output. There's also another caveat because
as far as I understand .ctors run in reverse order so when we do
the copy/mapping we need to reverse copy in the output if there's
more than one ctor. That's why I'd rather avoid this complicate logic
unless there's a real need.
An analogous reasoning holds for .dtors/.fini_array.
llvm-svn: 265085
Some targets might require creation of thunks. For example, MIPS targets
require stubs to call PIC code from non-PIC one. The patch implements
infrastructure for thunk code creation and provides support for MIPS
LA25 stubs. Any MIPS PIC code function is invoked with its address
in register $t9. So if we have a branch instruction from non-PIC code
to the PIC one we cannot make the jump directly and need to create a small
stub to save the target function address.
See page 3-38 ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf
- In relocation scanning phase we ask target about thunk creation necessity
by calling `TagetInfo::needsThunk` method. The `InputSection` class
maintains list of Symbols requires thunk creation.
- Reassigning offsets performed for each input sections after relocation
scanning complete because position of each section might change due
thunk creation.
- The patch introduces new dedicated value for DefinedSynthetic symbols
DefinedSynthetic::SectionEnd. Synthetic symbol with that value always
points to the end of the corresponding output section. That allows to
escape updating synthetic symbols if output sections sizes changes after
relocation scanning due thunk creation.
- In the `InputSection::writeTo` method we write thunks after corresponding
input section. Each thunk is written by calling `TargetInfo::writeThunk` method.
- The patch supports the only type of thunk code for each target. For now,
it is enough.
Differential Revision: http://reviews.llvm.org/D17934
llvm-svn: 265059
We have to check the final value that is written.
I don't think this has any real word implications (unless something
supports unaligned instructions), but unblocks simplifying the handling
of PC relative relocations.
llvm-svn: 265009
This reverts commit r264945.
The commit only removed an unreachable in a method with a covered switch, but
GCC is likely to warn on this, and the coding standards recommend just leaving
in the unreachable.
llvm-svn: 264983
make_dynamic_error_code was used to create a std::error_code with
a std::string message. Now that we are migrating to llvm::Error,
there are no calls to these make_dynamic_error_code methods.
There is one single call to make_dynamic_error_code remaining, the one
inside GenericError::convertToErrorCode(). That method is only called
from File::doParse() which should be a temporary situation. We need
to work out how to deal with File::parse() caching the error result from
doParse(). Caching errors isn't supported in the new scheme, and probably
isn't needed here, but we need to work that out.
Once thats done, dynamic error and all utilities around it can be deleted.
llvm-svn: 264982
These methods weren't really throwing errors. The only error used
was that a file could not be found, which isn't really an error at all
as we are searching paths and libraries for a file. All of the callers
also ignored errors and just used the returned path if one was available.
Changing to return Optional<StringRef> as that actually reflects what
we are trying to do here: optionally find a given path.
llvm-svn: 264979
These methods were responsible for some of the few remaining calls
to llvm::errorCodeToError. Converting them makes us have more Error's
in the api and fewer error_code's.
llvm-svn: 264974
If we make R_MIPS_LO16 a relative relocation, linker:
- never creates R_MIPS_COPY relocation for it
- attempts to create R_MIPS_REL32 dynamic relocation if R_MIPS_LO16's
target is a preemptible symbol
Differential Revision: http://reviews.llvm.org/D18607
llvm-svn: 264956
Pretty mechanical change here. Just replacing all the std::error_code() with
llvm::Error() and make_dynamic_error_code with make_error<GenericError>
llvm-svn: 264917
Windows seems to complain that the file cannot be removed because
it is still in use. We don't have to remove the file but instead
just overwrite it, so do that.
llvm-svn: 264915
Adds a GenericError class to lld/Core which can carry a string. This is
analygous to the dynamic_error we currently use in lld/Core.
Use this GenericError instead of make_dynamic_error_code. Also, provide
an implemention of GenericError::convertToErrorCode which for now converts
it in to the dynamic_error_code we used to have. This will go away once
all the APIs are converted.
llvm-svn: 264910
This patch add a TLS relax optimization test when transforming
Initial-Exec to Local-Exec for local symbols (which can not be preempted).
llvm-svn: 264903
gold and bfd do not include the undefined locals in symtab.
We have no reasons to support that either.
That fixes PR27016
Differential revision: http://reviews.llvm.org/D18554
llvm-svn: 264843
The original comments were separated by new code that is irrelevant to
the comment. This patch moves the comment to the right place and update it.
llvm-svn: 264816
This simplifies a few things
* Read the value as early as possible, instead of passing a pointer to
the location.
* Print the warning for missing pair close to where we find out it is
missing.
* Don't pass the value to relocateOne.
llvm-svn: 264802
Mips aligns PT_LOAD to 16 bits (0x10000). That means that the lower 16
bits are always the same, so we can, effectively, say that the
relocation is relative.
llvm-svn: 264761
Local symbol which requires GOT entry initialized by "page" address.
This address is high 16 bits of sum of the symbol value and the relocation
addend. In the relocation scanning phase final values of symbols are unknown
so to reduce number of allocated GOT entries do the following trick. Save
all output sections referenced by GOT relocations during the relocation
scanning phase. Then later in the `GotSection::finalize` method calculate
number of "pages" required to cover all saved output sections and allocate
appropriate number of GOT entries. We assume the worst case - each 64kb
page of the output section has at least one GOT relocation against it.
Differential Revision: http://reviews.llvm.org/D18349
llvm-svn: 264730
When R_X86_64_PC32/R_X86_64_32 relocations are
used against preemptible symbol and output is position independent,
error should be generated.
Differential revision: http://reviews.llvm.org/D18190
llvm-svn: 264707
Some optimizations, e.g. SimplifyLibCalls, can replace functions with
others as part of the lowering, e.g. printf => puts.
The new symbols don't have the isUsedInRegularObj flag set so they
don't get included in the final symbol table (and dynamic symbol
table), and the dynamic linker gets confused. Include them as a fix.
Differential Revision: http://reviews.llvm.org/D18357
llvm-svn: 264688
searchArchivesToOverrideTentativeDefinitions and
searchSharedLibrariesToOverrideTentativeDefinitions are always false.
For the dead flags, we have a fairly large amount of code which is
never be executed.
http://reviews.llvm.org/D17791
llvm-svn: 264653
IPO doesn't work very well across symbols referenced
by others TUs. The linker here tries to evaluate
which symbols are safe to internalize and switches
their linkage.
Differential Revision: http://reviews.llvm.org/D18415
llvm-svn: 264585
This flag disables link.exe's crash handler so that normal windows error
reporting and crash dumping occurs. For now it is reasonable for LLD to
ignore the flag.
Chromium is currently using this flag to collect minidumps of link.exe
crashing, and it breaks the LLD build.
llvm-svn: 264439
This patch simplifies the isRelRelative for AArch64 and add the missing
ones for bootstrap and test-suite. It also adds more testing for
shared object creation.
llvm-svn: 264322
The stack-size.yaml test had an empty atom content array. This is
legal, but asking a BumpPtrAllocator for 0 sized data may not be
legal. Instead just avoid requesting any data when we can just return
an empty ArrayRef instead.
llvm-svn: 264234
Its possible for file to have no entry atom which means that there
is no atom to check for being a thumb function. Instead just skip
the thumb check and set the entry address to 0, which matches the
current behaviour of getting a default initialised int from a map.
llvm-svn: 264233
On a 32-bit output, we may write LC_MAIN (which contains a uint64_t) to
an unaligned address. This changes it to use a memcpy instead which is UB safe.
llvm-svn: 264232
We were casting a potentially unaligned pointer to uint32_t and
dereferencing. As the pointer ultimately comes from the object file,
there's no way to guarantee alignment, so use the little32_t read instead.
Also, little32_t knows about endianness, so in theory this may have broken on
big endian machines.
llvm-svn: 264231
The .o path always makes sure to store a power of 2 value in the
Section alignment. However, the YAML code didn't verify this.
Added verification and updated all the tests which had a 3 but meant
to have 2^3.
llvm-svn: 264228
The size of a section can be zero, even when it contains atoms, so
long as all of the atoms are also size 0. In this case we were
allocating space for a 0 sized buffer.
Changed this to only allocate when we need the space, but also cleaned
up all the code to use MutableArrayRef instead of uint8_t* so its much much
safer as we get bounds checking on all of our section creation logic.
llvm-svn: 264204
On a 32-bit output, we may write LC_SOURCE_VERSION (which contains a uint64_t) to
an unaligned address. This changes it to use a memcpy instead which is UB safe.
llvm-svn: 264202
We were already copying this data to a temporary for endian swaps. Now
we just always copy it, but still only do the endian swaps when needed.
llvm-svn: 264172
Turns out that checking only x86 for empty atoms to fix UBSan then
requires the same code in the other targets too. Better to just
check this in the main run loop instead of in each target.
Should be NFC, other than fixing UBSan failures.
llvm-svn: 264116
This was caught by the UBSan bot. When the atom has no size, we would
issue a memcpy with size0 and a nullptr for the source.
Also, this code should never have references inside an empty atom so
add an assert for that while we're here.
llvm-svn: 264115
Ensure we keep the symbol we need to before it reaches
the Writer (and hit an assertion), changing its linkage
from linkonce_odr to weak. For a more detailed description
of the problem, see PR19901 where a similar problem was
fixed for the gold plugin. Thanks to Rafael for providing
a testcase.
llvm-svn: 264111
If the LHS of 'a = b' already had an atom in it then we wouldn't
call the destructor. This happens when we use something like
std::remove_if which is done in the CompactUnwindPass. Should fix
the leaks on the mach-o/unwind-info-simple-x86_64.yaml test case.
Lang and I are going to take a look at removing OwningAtomPtr in
favour of a std::unique_ptr but just trying to get the bots green
so we have a good baseline first.
llvm-svn: 264097
The code for LTO has been growing, so now is probably a good time to
move it to its own file. SymbolTable.cpp is for symbol table, and
because compiling bitcode files are semantically not a part of
symbol table, this is I think a good thing to do.
http://reviews.llvm.org/D18370
llvm-svn: 264091
OwningAtomPtr does not have OwningAtomPtr(OwningAtomPtr&) or the equivalent
operator= as we only want to use rvalue references in it.
SortKey didn't like this on MSVC as it was synthesizing SortKey(SortKey&) and
trying to use the OwningAtomPtr(OwningAtomPtr&) method which was private an
unimplemented.
Now we explicitly have the methods on SortKey so hopefully the bot will be
happier.
llvm-svn: 264077
The AtomVector class is an internal detail of File so I moved it
to be protected in r264067. However, the MSVC bots don't like the
global declarations of type File::AtomVector in File.cpp so it needs
to go back to being public for now.
llvm-svn: 264070
This is a re-commit of r264022 with a fix for MSVC. The issue there was
that the code was running DefinedAtom::~Atom() for some value and instead
needed to cast to Atom before running ~Atom. Original commit message follows.
Currently each File contains an BumpPtrAllocator in which Atom's are
allocated. Some Atom's contain data structures like std::vector which
leak as we don't run ~Atom when they are BumpPtrAllocate'd.
Now each File actually owns its Atom's using an OwningAtomPtr. This
is analygous to std::unique_ptr and may be replaced by it if possible.
An Atom can therefore only be owned by a single File, so the Resolver now
moves them from one File to another. The MachOLinkingContext owns the File's
and so clears all the Atom's in ~MachOLinkingContext, then delete's all the
File's. This makes sure all Atom's have been destructed before any of the
BumpPtrAllocator's in which they run have gone away.
Should hopefully fix the remaining leaks. Will keep an eye on the bots to
make sure.
llvm-svn: 264067
When a tls access is optimized, a group of relocations is converted at a
time.
We were already skipping relocations that were optimized out in
relocate, but not in scanRelocs.
This is a small optimization. I got here while working on a patch that
will always keep scanRelocs and relocate in sync.
llvm-svn: 264048
R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX relocations were added in latest ABI:
https://github.com/hjl-tools/x86-psABI/wiki/x86-64-psABI-r249.pdf
They should be generated instead of R_X86_64_GOTPCREL for cases
when relaxation is possible. Currently this patch just process them in the
same way like R_X86_64_GOTPCREL. That should work for now
and we can implement relaxations later.
There is no testcases provided as I think there is no way to generate
such relocations using llvm-mc atm.
Differential revision: http://reviews.llvm.org/D18301
llvm-svn: 264043
Now local symbols have SymbolBody so we can handle all kind of symbols
in the GotSection::addEntry method. The patch moves the code from
addMipsLocalEntry to addEntry. NFC.
Differential Revision: http://reviews.llvm.org/D18302
llvm-svn: 264032
This reverts commit r264022.
This breaks the Window's bots which don't like that i'm calling ~Atom when
the this pointer is a sublcass of Atom.
Reverting for now until I try find a better fix. I tried using std::unique_ptr with
a custom deleter as a quick fix, but it didn't work well in the YAML parser.
llvm-svn: 264023
Currently each File contains an BumpPtrAllocator in which Atom's are
allocated. Some Atom's contain data structures like std::vector which
leak as we don't run ~Atom when they are BumpPtrAllocate'd.
Now each File actually owns its Atom's using an OwningAtomPtr. This
is analygous to std::unique_ptr and may be replaced by it if possible.
An Atom can therefore only be owned by a single File, so the Resolver now
moves them from one File to another. The MachOLinkingContext owns the File's
and so clears all the Atom's in ~MachOLinkingContext, then delete's all the
File's. This makes sure all Atom's have been destructed before any of the
BumpPtrAllocator's in which they run have gone away.
Should hopefully fix the remaining leaks. Will keep an eye on the bots to
make sure.
llvm-svn: 264022
In trying to fix the leaks in the MachO lld codebase, we need to have
a better model for file and atom ownership. Having the context own
everything seems like the simplest model, so change all the passes to
allocate File's on the context instead of owning files as a member.
llvm-svn: 264004
Some declarations of memcpy (like glibc's for example) are attributed
with notnull which makes it UB for NULL to get passed in, even if the
memcpy count is zero.
To account for this, guard the memcpy with an appropriate precondition.
This should fix the last UBSan bug, exposed by the test suite, in the
COFF linker.
llvm-svn: 263919
LLD type-punned an integral type and a pointer type using a pointer
field. This is problematic because the pointer type has alignment
greater than some of the integral values.
This would be less problematic if a union was used but it turns out the
integral values are only present for a short, transient, amount of time.
Let's remove this undefined behavior by skipping the punning altogether
by storing the state in a separate memory location: a vector which
informs us which symbols to process for weak externs.
llvm-svn: 263918
Just ignore the -rpath-link command line
option in the same way like gold do.
Behavior of lld/gold differs from gnu ld here.
GNU ld tries to resolve undefined symbols in all
shared object files at link time.
Differential revision: http://reviews.llvm.org/D18269
llvm-svn: 263876
This is required to get 'clang -flto' to work transparently
with lld. Please refer to the short comment in the code
for a more detailed explanation.
llvm-svn: 263862
Some COFF tests used INT_MIN for the alignment of the directive section.
This is invalid; replace the alignment with something more sensible: 1.
llvm-svn: 263723
-pie
--pic-executable
Create a position independent executable. This is currently only
supported on ELF platforms. Position independent executables are
similar to shared libraries in that they are relocated by the
dynamic linker to the virtual address the OS chooses for them
(which can vary between invocations). Like normal dynamically
linked executables they can be executed and symbols defined in the
executable cannot be overridden by shared libraries.
Differential revision: http://reviews.llvm.org/D18183
llvm-svn: 263693
The YAML traits new's when not passed an allocator to parse data.
For atom types, this is a leak as we don't destruct atoms. For
the File here, we do actually destruct File's so that single case of
not using an allocator will be fine.
Should fix a bunch more leaks.
llvm-svn: 263680
In lld we allocate atoms on an allocator and so don't run their
destructors. This means we also shouldn't allocate memory inside
them without that also being on an allocator.
Reviewed by Lang Hames and Rafael Espindola.
llvm-svn: 263677
For now just treat such sections as non-mergeable.
Resubmit r263660 with test fix.
Differential Revision: http://reviews.llvm.org/D18225
llvm-svn: 263664
The current code for processCIE and processFDE returns out if it sees
any references. The problem with this is that some references could be
explicit in the binary, while others are implicit as they can be
inferred from the content of the EHFrame itself.
This change walks the references we have against the references we
need, and verifies that all explicit references are in the correct place,
and generates any missing implicit ones.
Reviewed by Lang Hames and Nick Kledzik.
Differential Revision: http://reviews.llvm.org/D15439
llvm-svn: 263590
This fixes a test which exposed an ASan issue.
We assumed that a symbol's section number had a corresponding section
without performing validation.
llvm-svn: 263558
The load configuration directory is a structure whose size varies as the
OS gains additional functionality. To account for this, the structure's
layout begins with a size field; this allows loaders to know which
fields are available.
However, LLD hard-coded the sizes (112 bytes for 64-bit and 64 for
32-bit). This means that we might not inform the loader of all the
pertinent fields or we might claim that there are more fields than are
actually present.
To correctly account for this, the size field must be loaded from the
_load_config_used symbol.
N.B. The COFF spec is either wrong or out of date, the load
configuration directory is not correctly documented in the
specification: it omits the size field.
llvm-svn: 263543
The TLS directory has a different layout depending on the bitness of the
machine the image will run on. LLD would always use the 64-bit TLS
directory for the data directory entry instead of an appropriately sized
TLS directory.
llvm-svn: 263539
-warn-common
Warn when a common symbol is combined with another common symbol
or with a symbol definition. Unix linkers allow this somewhat
sloppy practice, but linkers on some other operating systems do
not. This option allows you to find potential problems from
combining global symbols.
Differential revision: http://reviews.llvm.org/D17998
llvm-svn: 263413
We want to make SymbolBody the central place to query symbol information.
This patch also renames canBePreempted to isPreemptible because I feel that
the latter is slightly better (the former is three words and the latter
is two words.)
llvm-svn: 263386
The patch does not reduce the size of the code but makes
InputSectionBase::relocate cleaner a bit.
Differential Revision: http://reviews.llvm.org/D18119
llvm-svn: 263381
error returned true if there was an error. This allows us to replace
the code like this
if (EC) {
error(EC, "something failed");
return;
}
with
if (error(EC, "something failed"))
return;
I thought that that was a good idea, but it turned out that we only
have two places to use this pattern. So this patch removes that feature.
llvm-svn: 263362
At least Linux has the kernel configuration to include the first page
of the executable into core files. We want build ID section to be
included in core files to identify them.
Here is the link to the description about the kernel configuration.
097f70b3c4/fs/Kconfig.binfmt (L46)
llvm-svn: 263351
which was reverted because included
unrelative changes by mistake.
Original commit message:
[ELF] - Change all messages to lowercase to be consistent.
That is directly opposite to http://reviews.llvm.org/D18045,
which was reverted.
This patch changes all messages to start from lowercase letter if
they were not before.
That is done to be consistent with clang.
Differential revision: http://reviews.llvm.org/D18085
llvm-svn: 263337
This patch implements --build-id. After the linker creates an output file
in the memory buffer, it computes the FNV1 hash of the resulting file
and set the hash to the .note section as a build-id.
GNU ld and gold have the same feature, but their default choice of the
hash function is different. Their default is SHA1.
We made a deliberate choice to not use a secure hash function for the
sake of performance. Computing a secure hash is slow -- for example,
MD5 throughput is usually 400 MB/s or so. SHA1 is slower than that.
As a result, if you pass --build-id to gold, then the linker becomes about
10% slower than that without the option. We observed a similar degradation
in an experimental implementation of build-id for LLD. On the other hand,
we observed only 1-2% performance degradation with the FNV hash.
Since build-id is not for digital certificate or anything, we think that
a very small probability of collision is acceptable.
We considered using other signals such as using input file timestamps as
inputs to a secure hash function. But such signals would have an issue
with build reproducibility (if you build a binary from the same source
tree using the same toolchain, the build id should become the same.)
GNU linkers accepts --build-id=<style> option where style is one of
"MD5", "SHA1", or an arbitrary hex string. That option is out of scope
of this patch.
http://reviews.llvm.org/D18091
llvm-svn: 263292
That is directly opposite to http://reviews.llvm.org/D18045,
which was reverted.
This patch changes all messages to start from lowercase letter if
they were not before.
That is done to be consistent with clang.
Differential revision: http://reviews.llvm.org/D18085
llvm-svn: 263252
In lld we usually avoid hash lookups. In addition to that, IR names are
not fully mangled, so it is best to avoid using them whenever possible.
llvm-svn: 263248
It was discussed to make all messages be
lowercase to be consistent with clang.
(also reverts the r263128 which fixed
build bot fail after r263125)
Original commit message:
[ELF] - Consistent spelling for error/warning messages
Previously error and warnings were not consistent in lld.
Some of them started from lowercase letter, others from
uppercase. Also there was one or two which had a dot at the end.
This patch changes all messages to start from uppercase letter if
they were not before.
Differential revision: http://reviews.llvm.org/D18045
llvm-svn: 263240
It is really odd that Mips differentiates symbols that are born local
and those that become local because of hidden visibility. I don't know
enough mips to known if this is a bug or not.
llvm-svn: 263228
This patch adds --thread option and use parallel_for_each to write
sections in regular OutputSections.
This is the first patch to use more than one threads.
Note that --thread is off by default because it is experimental.
At this moment I still want to focus on single thread performance
because multi-threading is not a magic wand to fix performance
problems after all. It is generally very hard to make a slow program
faster by threads. Therefore, I want to make the linker as efficient
as possible first and then look for opportunity to make it even faster
using more than one core.
Here are some numbers to link programs with and without --threads
and using GNU gold. Numbers are in seconds.
Clang
w/o --threads 0.697
w --threads 0.528
gold 1.643
Scylla
w/o --threads 5.032
w --threads 4.935
gold 6.791
GNU gold
w/o --threads 0.550
w --threads 0.551
gold 0.737
I limited the number of cores these processes can use to 4 using
perf command, so although my machine has 20 physical cores, the
performance gain I observed should be reproducible with a machine
which is not as beefy as mine.
llvm-svn: 263190
This is reduced from an issue found in practice.
The original version of D18012 needed another patch to handle this, but
it now works since we are using a more correct GV->hasAppendingLinkage()
check that Rafael suggested.
This is what remains of that other patch.
llvm-svn: 263181
Summary:
More generally, appending linkage is a special case that we don't want
to create a SymbolBody for.
Reviewers: rafael, ruiu
Subscribers: Bigcheese, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D18012
llvm-svn: 263179
We can argue about a maximum alignment of a group of symbols,
but for each symbol, there is only one alignment.
So it is a bit weird that each symbol has a "maximum alignment".
llvm-svn: 263151
R_X86_64_DTPOFF64 was not handled properly.
Next sample app was impossible to link before this patch:
~/pg/release/bin/clang -target x86_64-pc-linux testthread.cpp -c -g
~/pg/d+a/bin/ld.lld testthread.o
"Unknown TLS optimization" (value was 17)
__thread int x = 0;
void _start() {
}
It works fine now.
Differential revision: http://reviews.llvm.org/D18039
llvm-svn: 263150
It looks a bit wierd that we have to initialize symbols for all ELFT
types when we use only one ELFT for link. We can only init those
that we need. Patch fixes it.
Differential revision: http://reviews.llvm.org/D18047
llvm-svn: 263133
(http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/builds/8662).
Test fails on linux only.
Original commit message:
[ELF] - Consistent spelling for error/warning messages
Previously error and warnings were not consistent in lld.
Some of them started from lowercase letter, others from
uppercase. Also there was one or two which had a dot at the end.
This patch changes all messages to start from uppercase letter if
they were not before.
Differential revision: http://reviews.llvm.org/D18045
llvm-svn: 263128
Previously error and warnings were not consistent in lld.
Some of them started from lowercase letter, others from
uppercase. Also there was one or two which had a dot at the end.
This patch changes all messages to start from uppercase letter if
they were not before.
Differential revision: http://reviews.llvm.org/D18045
llvm-svn: 263125
Summary:
They are needed for inline asm during LTO.
In particular we hit the report_fatal_error on
llvm/lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp:138
LLVM ERROR: Inline asm not supported by this streamer because we don't have an asm parser for this target
Reviewers: ruiu, rafael
Subscribers: Bigcheese, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D18027
llvm-svn: 263094
Summary:
This implements another part of -save-temps.
After this, the only remaining part is dumping the optimized bitcode. But
currently LLD's LTO doesn't have a non-intrusive place to put this.
Eventually we probably will and it will make sense to add it then.
Reviewers: ruiu, rafael
Subscribers: joker.eph, Bigcheese, llvm-commits
Differential Revision: http://reviews.llvm.org/D18009
llvm-svn: 263070
Summary:
This is useful for debugging issues with LTO.
The option follows the analogous option in ld64 and the gold plugin (per
Rafael's suggestion).
For starters, this only dumps the combined bitcode file.
In a future patch I will add dumping for the .o file.
The naming of the output follows ld64's convention which is slightly more
consistent IMO (consistent `.lto.<extension>` for all the files).
Reviewers: rafael, ruiu
Subscribers: joker.eph, Bigcheese, llvm-commits
Differential Revision: http://reviews.llvm.org/D18006
llvm-svn: 263055
Summary:
At the very least we hit
Assertion failed: (((Flags & RF_HaveUnmaterializedMetadata) || Node->isResolved()) && "Unexpected unresolved node"), function MapMetadataImpl, file /Users/Sean/pg/llvm/lib/Transforms/Utils/ValueMapper.cpp, line 375.
on the included test case.
We currently do things like parse the module twice to keep the
implementation minimal. I think it makes sense to add start with eager
loading for similar reasons.
Reviewers: rafael
Subscribers: ruiu, Bigcheese, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D17982
llvm-svn: 263045
Each object file compiled in split stack mode will have an empty
section with a special name: .note.GNU-split-stack
We don't support this in linker now, so patch just adds an error out for that.
Differential revision: http://reviews.llvm.org/D17918
llvm-svn: 263039
Summary:
Is there any other code needed for correctly handling appending linkage?
Do we need to do something more with @llvm.global_ctors in
SymbolTable.cpp:addBitcodeFile; otherwise the combined bitcode module
won't have all the global ctors.
Reviewers: rafael
Subscribers: Bigcheese, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D17975
llvm-svn: 262992
Summary:
This causes the issue in PR26872 to go away now that we aren't creating
symbols for the string literals, but that may just be concealing a
deeper problem, so best to keep that PR open.
Reviewers: rafael
Subscribers: Bigcheese, llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D17971
llvm-svn: 262968
It was a badly specified hack for when a tls relocation should be
propagated to the dynamic relocation table.
This replaces it with a not as bad hack of saying that a local dynamic
tls relocation is never preempted.
I will try to remove even that second hack in the next patch.
llvm-svn: 262955
It was causing errors like
/lib/libc.so.6 is incompatible with elf_x86_64
when linking on Fedora.
Every system has different default paths. It seems better to just trust
the driver to pass the correct -L options.
This reverts commit 262910.
llvm-svn: 262941
Sean Silva