Column information is present in CodeView when the line table subsection
has bit 0 set to 1 in it's flags field. The column information is
represented as a pair of 16-bit quantities: a starting and ending
column. This information is present at the end of the chunk, after all
the line-PC pairs.
llvm-svn: 241764
When talking about the virtual address of sections the coff spec says:
... for simplicity, compilers should set this to zero. Otherwise, it is an
arbitrary value that is subtracted from offsets during relocation.
We don't currently subtract it, so check that it is zero.
If some producer does create such files, we can change getRelocationOffset
instead.
llvm-svn: 241447
This function can really fail since the string table offset can be out of
bounds.
Using ErrorOr makes sure the error is checked.
Hopefully a lot of the boilerplate code in tools/* can go away once we have
a diagnostic manager in Object.
llvm-svn: 241297
This also improves the logic of what is an error:
* getSection(uint_32): only return an error if the index is out of bounds. The
index 0 corresponds to a perfectly valid entry.
* getSection(Elf_Sym): Returns null for symbols that normally don't have
sections and error for out of bound indexes.
In many places this just moves the report_fatal_error up the stack, but those
can then be fixed in smaller patches.
llvm-svn: 241156
This moves the error checking for string tables to getStringTable which returns
an ErrorOr<StringRef>.
This improves error checking, makes it uniform across all string tables and
makes it possible to check them once instead of once per name.
llvm-svn: 240950
It was a fairly broken concept for an ELF only class.
An ELF file can have two symbol tables, but they have exactly the same
format. There is no concept of a dynamic or a static symbol. Storing this
on the iterator also makes us do more work per symbol than necessary. To fetch
a name we would:
* Find if we had a static or a dynamic symbol.
* Look at the corresponding symbol table and find the string table section.
* Look at the string table section to fetch its contents.
* Compute the name as a substring of the string table.
All but the last step can be done per symbol table instead of per symbol. This
is a step in that direction.
llvm-svn: 240939
The parser provides a convenient interface for reading llvm stackmap v1 sections
in object files.
This patch also includes a new option for llvm-readobj, '-stackmap', which uses
the parser to pretty-print stackmap sections for debugging/testing purposes.
llvm-svn: 240860
This is still a really odd function. Most calls are in object format specific
contexts and should probably be replaced with a more direct query, but at least
now this is not too obnoxious to use.
llvm-svn: 240777
Summary: This will be used by the R600 backend.
Reviewers: chandlerc, rafael
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10389
llvm-svn: 240329
There are 3 types of relocations on MachO
* Scattered
* Section based
* Symbol based
On ELF and COFF relocations are symbol based.
We were in the strange situation that we abstracted over two of them. This makes
section based relocations MachO only.
llvm-svn: 240149
In a relocation target can take 3 basic forms
* A r_value in scattered relocations.
* A symbol in external relocations.
* A section is non-external relocations.
Have the dump reflect that. With this change we go from
CHECK-NEXT: Extern: 0
CHECK-NEXT: Type: X86_64_RELOC_SUBTRACTOR (5)
CHECK-NEXT: Symbol: 0x2
CHECK-NEXT: Scattered: 0
To just
// CHECK-NEXT: Type: X86_64_RELOC_SUBTRACTOR (5)
// CHECK-NEXT: Section: __data (2)
Since the relocation is with a section, we print the seciton name and don't
need to say that it is not scattered or external.
Someone motivated can add further special cases for things like
ARM64_RELOC_ADDEND and ARM_RELOC_PAIR.
llvm-svn: 240073
The underlaying issues is that this code can't really know if an OS specific or
processor specific section number should return true or false.
One option would be to assert or return an error, but that looks like over
engineering since extensions are not that common.
It seems better to have these be direct implementation of the ELF spec so that
they are natural for someone familiar with ELF reading the code.
Code that does have to handle OS/Architecture specific values can do it at
a higher level.
llvm-svn: 239618
make_error_code(object_error) is slow because object::object_category()
uses a ManagedStatic variable. But the real problem is that the function is
called too frequently. This patch uses std::error_code() instead of
object_error::success. In most cases, we return "success", so this patch
reduces number of function calls to that function.
http://reviews.llvm.org/D10333
llvm-svn: 239409
The ELF spec is very clear:
-----------------------------------------------------------------------------
If the value is non-zero, it represents a string table index that gives the
symbol name. Otherwise, the symbol table entry has no name.
--------------------------------------------------------------------------
In particular, a st_name of 0 most certainly doesn't mean that the symbol has
the same name as the section.
llvm-svn: 238899
CloudABI is a POSIX-like runtime environment built around the concept of
capability-based security. More details:
https://github.com/NuxiNL/cloudlibc
CloudABI uses its own ELFOSABI number. This number has been allocated by
the maintainers of ELF a couple of days ago.
Reviewed by: echristo
llvm-svn: 231681
This will help us study the format of individual symbol
records more closely.
Differential Revision: http://reviews.llvm.org/D7664
Reviewed by: Timur Iskhodzhanov
llvm-svn: 229730
Add an additional based relocation to the enumeration of based relocation names.
The lack of the enumerator value causes issues when inspecting WoA binaries.
llvm-svn: 226314
utils/sort_includes.py.
I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.
llvm-svn: 225974
Fix ARMAttributeParser::CPU_arch_profile so that it doesn't switch on the value
'0' as a legal value of this build attribute.
Change-Id: Ie05a08900a82bb10b78c841b437df747ce3bb38e
llvm-svn: 222743
It printed out base relocation table header as table entry.
This patch also makes llvm-readobj to not skip ABSOLUTE entries
becuase it was confusing.
llvm-svn: 222299
We were a little lax in a few areas:
- We pretended that import libraries were like any old COFF file, they
are not. In fact, they aren't really COFF files at all, we should
probably grow some specialized functionality to handle them smarter.
- Our symbol iterators were more than happy to attempt to go past the
end of the symbol table if you had a symbol with a bad list of
auxiliary symbols.
llvm-svn: 222124
On error conditions, relocAddressLess might claim that a value is less
than itself. Instead, abort llvm-readobj. No functionality change
intended.
llvm-svn: 221872
lib/Object is supposed to be robust to malformed object files. Don't
assert if we don't have a symbol table. I'll try to come up with a test
case later.
llvm-svn: 221870
Revert "Correctly handle references to section symbols."
Revert "Allow forward references to section symbols."
Rui found a regression I am debugging.
llvm-svn: 220010
When processing assembly like
.long .text
we were creating a new undefined symbol .text. GAS on the other hand would
handle that as a reference to the .text section.
This patch implements that by creating the section symbols earlier so that
they are visible during asm parsing.
The patch also updates llvm-readobj to print the symbol number in the relocation
dump so that the test can differentiate between two sections with the same name.
llvm-svn: 219829
There are two methods in SectionRef that can fail:
* getName: The index into the string table can be invalid.
* getContents: The section might point to invalid contents.
Every other method will always succeed and returning and std::error_code just
complicates the code. For example, a section can have an invalid alignment,
but if we are able to get to the section structure at all and create a
SectionRef, we will always be able to read that invalid alignment.
llvm-svn: 219314
PE/COFF has a special section (.drectve) which can be used to pass options to
the linker (similar to LC_LINKER_OPTION). Add support to llvm-readobj to print
the contents of the section for tests.
llvm-svn: 219228
Codeview line tables for functions in different sections refer to a common
STRING_TABLE_SUBSECTION for filenames.
This happens when building with -Gy or with inline functions with MSVC.
Original patch by Jeff Muizelaar!
llvm-svn: 219125
This patch defines a new iterator for the imported symbols.
Make a change to COFFDumper to use that iterator to print
out imported symbols and its ordinals.
llvm-svn: 218915
When the flag is given, the command prints out the COFF import table.
Currently only the import table directory will be printed.
I'm going to make another patch to print out the imported symbols.
The implementation of import directory entry iterator in
COFFObjectFile.cpp was buggy. This patch fixes that too.
http://reviews.llvm.org/D5569
llvm-svn: 218891
Users of getSectionContents shouldn't try to pass in BSS or virtual
sections. In all instances, this is a bug in the code calling this
routine.
N.B. Some COFF implementations (like CL) will mark their BSS sections as
taking space on disk. This would confuse COFFObjectFile into thinking
the section is larger than the file.
llvm-svn: 218549
Teach WinCOFFObjectWriter how to write -mbig-obj style object files;
these object files allow for more sections inside an object file.
Our support for BigObj is notably different from binutils and cl: we
implicitly upgrade object files to BigObj instead of asking the user to
compile the same file *again* but with another flag. This matches up
with how LLVM treats ELF variants.
This was tested by forcing LLVM to always emit BigObj files and running
the entire test suite. A specific test has also been added.
I've lowered the maximum number of sections in a normal COFF file,
VS "14" CTP 3 supports no more than 65279 sections. This is important
otherwise we might not switch to BigObj quickly enough, leaving us with
a COFF file that we couldn't link.
yaml2obj support is all that remains to implement.
Differential Revision: http://reviews.llvm.org/D5349
llvm-svn: 217812
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
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
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
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
Add the new AppContainer characteristic which is import for Windows Store
(Metro) compatible applications. Add the new Control Flow Guard flag to bring
the enumeration up to date with the current values as of Windows 8.1.
llvm-svn: 211855
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 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
Add a brief explanation of the data section layout for the unwind data that the
Windows on ARM EH models. This is simply to provide a rough idea of the layout
of the code involved in the decoding of the unwinding. Details on the involved
data structures are available in the associated support header. The bulk of it
is related to printing out the byte-code to help validate generation of WoA EH.
No functional change.
llvm-svn: 210397
Add support to llvm-readobj to decode Windows ARM Exception Handling data. This
uses the previously added datastructures to decode the information into a format
that can be used by tests. This is a necessary step to add support for emitting
Windows on ARM exception handling information.
A fair amount of formatting inspiration is drawn from the Win64 EH printer as
well as the ARM EHABI printer. This allows for a reasonably thorough look into
the encoded data.
llvm-svn: 210192
Remove the use of the std::function and replace the capturing lambda with a
non-capturing one, opting to pass the user data down to the context. This is
needed as std::function is not yet available on all hosted platforms (it
requires RTTI, which breaks on Windows).
Thanks to Nico Rieck for pointing this out!
llvm-svn: 209607
Move the implementation of the Win64 EH printer from the COFFDumper into its own
class. This is in preparation for adding support to print ARM EH information.
The only real change here is in printUnwindInfo where we now lambda lift the
implicit this parameter for the resolveFunction. Also setup the printing to
handle ARM. This now has set the stage to introduce ARM EH printing.
llvm-svn: 209606
Make the use of the cache more transparent to the users. There is no reason
that the cached entries really need to be passed along. The overhead for doing
so is minimal: a single extra parameter. This requires that some standalone
functions be brought into the COFFDumper class so that they may access the
cache.
llvm-svn: 209604
Switch to use references for parameters that are guaranteed to be non-null.
Simplifies the code a slight bit in preparation for another change.
llvm-svn: 209603
If a filename is a multiple of 18 characters, there will be no null-terminator.
This will result in an invalid access by the constructed StringRef. Add a test
case to exercise this and fix that handling. Address this same vulnerability in
llvm-readobj as well.
llvm-svn: 206145
We need .symtab_shndxr if and only if a symbol references a section with an
index >= 0xff00.
The old code was trying to figure out if the section was needed ahead of time,
making it a fairly dependent on the code actually writing the table. It was
also somewhat conservative and would create the section in cases where it was
not needed.
If I remember correctly, the old structure was there so that the sections were
created in the same order gas creates them. That was valuable when MC's support
for ELF was new and we tested with elf-dump.py.
This patch refactors the symbol table creation to another class and makes it
obvious that .symtab_shndxr is really only created when we are about to output
a reference to a section index >= 0xff00.
While here, also improve the tests to use macros. One file is one section
short of needing .symtab_shndxr, the second one has just the right number.
llvm-svn: 204769
The current state of affairs has auxiliary symbols described as a big
bag of bytes. This is less than satisfying, it detracts from the YAML
file as being human readable.
Instead, allow for symbols to optionally contain their auxiliary data.
This allows us to have a much higher level way of describing things like
weak symbols, function definitions and section definitions.
This depends on D3105.
Differential Revision: http://llvm-reviews.chandlerc.com/D3092
llvm-svn: 204214
Summary: These definitions are useful to other aspects of LLVM, move them out.
Reviewers: rafael, nrieck, ruiu
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D3105
llvm-svn: 204213
Since our error_category is based on the std one, we should have the
same visibility for the constructor. This also allows us to avoid
using the _do_message implementation detail in our own categories.
llvm-svn: 203998
The official specifications state the name to be ARMNT (as per the Microsoft
Portable Executable and Common Object Format Specification v8.3).
llvm-svn: 203530
This compiles with no changes to clang/lld/lldb with MSVC and includes
overloads to various functions which are used by those projects and llvm
which have OwningPtr's as parameters. This should allow out of tree
projects some time to move. There are also no changes to libs/Target,
which should help out of tree targets have time to move, if necessary.
llvm-svn: 203083
In some cases it is possible to have a personality 0 unwinding opcodes in the
extab (such as when .handlerdata is used in the assembly). Simply decode the 3
opcodes for that case.
llvm-svn: 201030
utohexstr provides a temporary string, making it unsafe to use with the Twine
interface which will not copy the string. Switch to using std::string.
llvm-svn: 200457
exp2 is not available on Windows. Fortunately, we are calculating powers of 2
with expontents within the range of [4,12]. Simply use an equivalent bitshift
operation to repair compilation with MSVC which does not provide this standard
function.
llvm-svn: 200454
Enhance the ARM specific parsing support in llvm-readobj to support attributes.
This allows for simpler tests to validate encoding of the build attributes as
specified in the ARM ELF specification.
llvm-svn: 200450
None of the object file formats reported error on iterator increment. In
retrospect, that is not too surprising: no object format stores symbols or
sections in a linked list or other structure that requires chasing pointers.
As a consequence, all error checking can be done on begin() and end().
This reduces the text segment of bin/llvm-readobj in my machine from 521233 to
518526 bytes.
llvm-svn: 200442
That bit is not documented in the PE/COFF spec published by Microsoft, so we
don't know the official name of it. I named this bit
IMAGE_DLL_CHARACTERISTICS_HIGH_ENTROPY_VIRTUAL_ADDRESS because the bit is
reported as "high entropy virtual address" by dumpbin.exe,
llvm-svn: 200121
PE32+ supports 64 bit address space, but the file format remains 32 bit.
So its file format is pretty similar to PE32 (32 bit executable). The
differences compared to PE32 are (1) the lack of "BaseOfData" field and
(2) some of its data members are 64 bit.
In this patch, I added a new member function to get a PE32+ Header object to
COFFObjectFile class and made llvm-readobj to use it.
llvm-svn: 200117
Add support to llvm-readobj to decode the actual opcodes. The ARM EHABI opcodes
are a variable length instruction set that describe the operations required for
properly unwinding stack frames.
The primary motivation for this change is to ease the creation of tests for the
ARM EHABI object emission as well as the unwinding directive handling in the ARM
IAS.
Thanks to Logan Chien for an extra test case!
llvm-svn: 199708
I did write a version returning ErrorOr<OwningPtr<Binary> >, but it is too
cumbersome to use without std::move. I will keep the patch locally and submit
when we switch to c++11.
llvm-svn: 199326
Rename bytecode to opcodes to make it more clear. Change an impossible case to
llvm_unreachable instead. Avoid allocation of a buffer by modifying the
PrintOpcodes iteration.
llvm-svn: 198848
This adds some preliminary support for decoding ARM EHABI unwinding information.
The major functionality that remains from complete support is bytecode
translation.
Each Unwind Index Table is printed out as a separate entity along with its
section index, name, offset, and entries.
Each entry lists the function address, and if possible, the name, of the
function to which it corresponds. The encoding model, personality routine or
index, and byte code is also listed.
llvm-svn: 198734
* ELFTypes.h contains template magic for defining types based on endianess, size, and alignment.
* ELFFile.h defines the ELFFile class which provides low level ELF specific access.
* ELFObjectFile.h contains ELFObjectFile which uses ELFFile to implement the ObjectFile interface.
llvm-svn: 188022
The original change was rolled back in r186627 because of test
failures on the big endian machine. I believe I fixed the issue
so re-submitting.
llvm-svn: 186734
Summary:
Dump optional data directory entries in the PE/COFF header, so that
we can test the output of LLD linker. This patch updates the test binary
file, but the source of the binary is the same. I just re-linked the file.
I don't know how the previous file was linked, but the previous file did
not have any data directory entries for some reason.
Reviewers: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1148
llvm-svn: 186623
These records are mandatory for executables and are used by the loader.
Reviewers: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D939
llvm-svn: 183852
In ELF (as in MachO), not all relocations point to symbols. Represent this
properly by using a symbol_iterator instead of a SymbolRef. Update llvm-readobj
ELF's dumper to handle relocatios without symbols.
llvm-svn: 183284
Michael J. Spencer