This format is simply a regular object file with the bitcode stored in a
section named ".llvmbc", plus any number of other (non-allocated) sections.
One immediate use case for this is to accommodate compilation processes
which expect the object file to contain metadata in non-allocated sections,
such as the ".go_export" section used by some Go compilers [1], although I
imagine that in the future we could consider compiling parts of the module
(such as large non-inlinable functions) directly into the object file to
improve LTO efficiency.
[1] http://golang.org/doc/install/gccgo#Imports
Differential Revision: http://reviews.llvm.org/D4371
llvm-svn: 218078
This finishes the ability of llvm-objdump to print out all information from
the LC_DYLD_INFO load command.
The -bind option prints out symbolic references that dyld must resolve
immediately.
The -lazy-bind option prints out symbolc reference that are lazily resolved on
first use.
The -weak-bind option prints out information about symbols which dyld must
try to coalesce across images.
llvm-svn: 217853
Similar to my previous -exports-trie option, the -rebase option dumps info from
the LC_DYLD_INFO load command. The rebasing info is a list of the the locations
that dyld needs to adjust if a mach-o image is not loaded at its preferred
address. Since ASLR is now the default, images almost never load at their
preferred address, and thus need to be rebased by dyld.
llvm-svn: 217709
This adds support for reading the "bigobj" variant of COFF produced by
cl's /bigobj and mingw's -mbig-obj.
The most significant difference that bigobj brings is more than 2**16
sections to COFF.
bigobj brings a few interesting differences with it:
- It doesn't have a Characteristics field in the file header.
- It doesn't have a SizeOfOptionalHeader field in the file header (it's
only used in executable files).
- Auxiliary symbol records have the same width as a symbol table entry.
Since symbol table entries are bigger, so are auxiliary symbol
records.
Write support will come soon.
Differential Revision: http://reviews.llvm.org/D5259
llvm-svn: 217496
Summary:
Until r216870 LLVMCreateObjectFile returned nullptr in case of an error,
so callers could check if the call was successful. Now, it always
returns an OwningBinary wrapped as an LLVMObjectFileRef, so callers
can't check if the call was successul.
This results in a segfault running e.g.
llvm-c-test --object-list-sections < /dev/null
So the old behaviour should be restored.
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5143
llvm-svn: 217279
I took a guess at the changes to the gold plugin, because that doesn't
seem to build by default for me. Not sure what dependencies I might be
missing for that.
llvm-svn: 217056
This forces callers to use std::move when calling it. It is somewhat odd to have
code with std::move that doesn't always move, but it is also odd to have code
without std::move that sometimes moves.
llvm-svn: 217049
An unpleasant surprise while migrating unique_ptrs (see changes in
lib/Object): ErrorOr<int*> was implicitly convertible to
ErrorOr<std::unique_ptr<int>>.
Keep the explicit conversions otherwise it's a pain to convert
ErrorOr<int*> to ErrorOr<std::unique_ptr<int>>.
I'm not sure if there should be more SFINAE on those explicit ctors (I
could check if !is_convertible && is_constructible, but since the ctor
has to be called explicitly I don't think there's any need to disable
them when !is_constructible - they'll just fail anyway. It's the
converting ctors that can create interesting ambiguities without proper
SFINAE). I had to SFINAE the explicit ones because otherwise they'd be
ambiguous with the implicit ones in an explicit context, so far as I
could tell.
The converting assignment operators seemed unnecessary (and similarly
buggy/dangerous) - just rely on the converting ctors to convert to the
right type for assignment instead.
llvm-svn: 217048
MachOObjectFile in lib/Object currently has no support for parsing the rebase,
binding, and export information from the LC_DYLD_INFO load command in final
linked mach-o images. This patch adds support for parsing the exports trie data
structure. It also adds an option to llvm-objdump to dump that export info.
I did the exports parsing first because it is the hardest. The information is
encoded in a trie structure, but the standard ObjectFile way to inspect content
is through iterators. So I needed to make an iterator that would do a
non-recursive walk through the trie and maintain the concatenation of edges
needed for the current string prefix.
I plan to add similar support in MachOObjectFile and llvm-objdump to
parse/display the rebasing and binding info too.
llvm-svn: 216808
The attached patch simplifies a few interfaces that don't need to take
ownership of a buffer.
For example, both parseAssembly and parseBitcodeFile will parse the
entire buffer before returning. There is no need to take ownership.
Using a MemoryBufferRef makes it obvious in the type signature that
there is no ownership transfer.
llvm-svn: 216488
Owning the buffer is somewhat inflexible. Some Binaries have sub Binaries
(like Archive) and we had to create dummy buffers just to handle that. It is
also a bad fit for IRObjectFile where the Module wants to own the buffer too.
Keeping this ownership would make supporting IR inside native objects
particularly painful.
This patch focuses in lib/Object. If something elsewhere used to own an Binary,
now it also owns a MemoryBuffer.
This patch introduces a few new types.
* MemoryBufferRef. This is just a pair of StringRefs for the data and name.
This is to MemoryBuffer as StringRef is to std::string.
* OwningBinary. A combination of Binary and a MemoryBuffer. This is needed
for convenience functions that take a filename and return both the
buffer and the Binary using that buffer.
The C api now uses OwningBinary to avoid any change in semantics. I will start
a new thread to see if we want to change it and how.
llvm-svn: 216002
file with -macho, the Mach-O specific object file parser option.
After some discussion I chose to do this implementation contained in the logic
of llvm-objdump’s MachODump.cpp using a second disassembler for thumb when
needed and with updates mostly contained in the MachOObjectFile class.
llvm-svn: 215931
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
llvm-svn: 215558
MachOObjectFile::getArch(uint32_t CPUType, uint32_t CPUSubType) .
Upcoming changes will cause existing test cases to use this but
I wanted to check in this obvious change separately.
llvm-svn: 215150
Having both Triple::arm64 and Triple::aarch64 is extremely confusing, and
invites bugs where only one is checked. In reality, the only legitimate
difference between the two (arm64 usually means iOS) is also present in the OS
part of the triple and that's what should be checked.
We still parse the "arm64" triple, just canonicalise it to Triple::aarch64, so
there aren't any LLVM-side test changes.
llvm-svn: 213743
createBinary documented that it destroyed the parameter in error cases,
though by observation it does not. By passing the unique_ptr by value
rather than lvalue reference, callers are now explicit about passing
ownership and the function implements the documented contract. Remove
the explicit documentation, since now the behavior cannot be anything
other than what was documented, so it's redundant.
Also drops a unique_ptr::release in llvm-nm that was always run on a
null unique_ptr anyway.
llvm-svn: 213557
This adds initial support for PPC32 ELF PIC (Position Independent Code; the
-fPIC variety), thus rectifying a long-standing deficiency in the PowerPC
backend.
Patch by Justin Hibbits!
llvm-svn: 213427
The registration scheme used in r211652 violated the read-only contract of
MemoryBuffer. This caused crashes in llvm-rtdyld where macho objects were backed
by read-only mmap'd memory.
llvm-svn: 213086
It is not clear if llvm.global_ctors should or should not be in llvm.metadata,
but in practice it is not and we need to ignore it for LTO.
llvm-svn: 212351
IRObjectFile provides all the logic for producing mangled names and getting
symbols from inline assembly.
LTOModule then adds logic for linking specific tasks, like constructing
llvm.compiler_user or extracting linker options from the bitcode.
The rule of the thumb is that IRObjectFile has the functionality that is
needed by both LTO and llvm-ar.
llvm-svn: 212349
There were two issues here:
1. At the very least, scattered relocations cannot use the same code to
determine the corresponding symbol being referred to. For some reason we
pretend there is no symbol, even when one actually exists in the symtab, so to
match this behaviour getRelocationSymbol should simply return symbols_end for
scattered relocations.
2. Printing "-" when we can't get a symbol (including the scattered case, but
not exclusively), isn't that helpful. In both cases there *is* interesting
information in that field, so we should print it. As hex will do.
Small part of rdar://problem/17553104
llvm-svn: 212332
Now that we have a lib/MC/MCAnalysis, the dependency was there just because
of two helper classes. Move the two over to MC.
This will allow IRObjectFile to parse inline assembly.
llvm-svn: 212248
universal file. This also includes support for -arch all, selecting the host
architecture by default from a universal file and checking if -arch is used
with a standard Mach-O it matches that architecture.
llvm-svn: 212054
string_ostream is a safe and efficient string builder that combines opaque
stack storage with a built-in ostream interface.
small_string_ostream<bytes> additionally permits an explicit stack storage size
other than the default 128 bytes to be provided. Beyond that, storage is
transferred to the heap.
This convenient class can be used in most places an
std::string+raw_string_ostream pair or SmallString<>+raw_svector_ostream pair
would previously have been used, in order to guarantee consistent access
without byte truncation.
The patch also converts much of LLVM to use the new facility. These changes
include several probable bug fixes for truncated output, a programming error
that's no longer possible with the new interface.
llvm-svn: 211749
This makes the buffer ownership on error conditions very natural. The buffer
is only moved out of the argument if an object is constructed that now
owns the buffer.
llvm-svn: 211546
This allows us to just use a std::unique_ptr to store the pointer to the buffer.
The flip side is that they have to support releasing the buffer back to the
caller.
Overall this looks like a more efficient and less brittle api.
llvm-svn: 211542
fat files) to print “ (for architecture XYZ)” for fat files with more than
one architecture to be like what the darwin tools do for fat files.
Also clean up the Mach-O printing of archive membernames in llvm-nm to use
the darwin form of "libx.a(foo.o)".
llvm-svn: 211316
fat files containing archives.
Also fix a bug in MachOUniversalBinary::ObjectForArch::ObjectForArch()
where it needed a >= when comparing the Index with the number of
objects in a fat file. As the index starts at 0.
llvm-svn: 211230
This makes llvm-nm ignore members that are not sufficiently aligned for
lib/Object to handle.
These archives are invalid. GNU AR is able to handle this, but in general
just warns about broken archive members.
We should probably start warning too, but for now just make sure llvm-nm
exits with an 0.
llvm-svn: 211036
This code was never being used and any use of it would look fairly strange.
For example, it would try to map a object_error::parse_failed to
std::errc::invalid_argument.
llvm-svn: 210912
The idea of this patch is to turn llvm/Support/system_error.h into a
transitional header that just brings in the erorr_code api to the llvm
namespace. I will remove it shortly afterwards.
The cases where the general idea needed some tweaking:
* std::errc is a namespace in msvc, so we cannot use "using std::errc". I could
add an #ifdef, but there were not that many uses, so I just added std:: to
them in this patch.
* Template specialization had to be moved to the std namespace in this
patch set already.
* The msvc implementation of default_error_condition doesn't seem to
provide the same transformations as we need. Not too surprising since
the standard doesn't actually say what "equivalent" means. I fixed the
problem by keeping our old mapping and using it at error_code
construction time.
Despite these shortcomings I think this is still a good thing. Some reasons:
* The different implementations of system_error might improve over time.
* It removes 925 lines of code from llvm already.
* It removes 6313 bytes from the text segment of the clang binary when
it is built with gcc and 2816 bytes when building with clang and
libstdc++.
llvm-svn: 210687
This is a first step in seeing if it is possible to make llvm-nm produce
the same output as darwin's nm(1). Darwin's default format is bsd but its
-m output prints the longer Mach-O specific details. For now I added the
"-format darwin" to do this (whos name may need to change in the future).
As there are other Mach-O specific flags to nm(1) which I'm hoping to add some
how in the future. But I wanted to see if I could get the correct output for
-m flag using llvm-nm and the libObject interfaces.
I got this working but would love to hear what others think about this approach
to getting object/format specific details printed with llvm-nm.
llvm-svn: 210285
field represents ELF section header sh_info field and does not have any
sense for regular sections. Its interpretation depends on section type.
llvm-svn: 209801
Some bit-set fields used in ELF file headers in fact contain two parts.
The first one is a regular bit-field. The second one is an enumeraion.
For example ELF header `e_flags` for MIPS target might contain the
following values:
Bit-set values:
EF_MIPS_NOREORDER = 0x00000001
EF_MIPS_PIC = 0x00000002
EF_MIPS_CPIC = 0x00000004
EF_MIPS_ABI2 = 0x00000020
Enumeration:
EF_MIPS_ARCH_32 = 0x50000000
EF_MIPS_ARCH_64 = 0x60000000
EF_MIPS_ARCH_32R2 = 0x70000000
EF_MIPS_ARCH_64R2 = 0x80000000
For printing bit-sets we use the `yaml::IO::bitSetCase()`. It does not
support bit-set/enumeration combinations and prints too many flags from
an enumeration part. This patch fixes this problem. New method
`yaml::IO::maskedBitSetCase()` handle "enumeration" part of bitset
defined by provided mask.
Patch reviewed by Nick Kledzik and Sean Silva.
llvm-svn: 209504
for undefined symbols, so it matches what COFFObjectFile::getSymbolAddress
does. This allows llvm-nm to print spaces instead of 0’s for the value
of undefined symbols in Mach-O files.
To make this change other uses of MachOObjectFile::getSymbolAddress
are updated to handle when the Value is returned as UnknownAddressOrSize.
Which is needed to keep two of the ExecutionEngine tests working for example.
llvm-svn: 209253
