In `MachOObjectFile::getSymbolType` we currently always return `SymbolRef::ST_Function` for symbols from any section. In order for llvm-symbolizer to correctly symbolize Mach-O globals, symbols from data and BSS sections should return `SymbolRef::ST_Data`.
Differential Revision: http://reviews.llvm.org/D14576
llvm-svn: 252867
from malformed Mach-O files that caused a crash because of a
section header had a size that extended past the end of the file.
rdar://22983603
llvm-svn: 249768
While introducing support for MinVersionLoadCommand in llvm-readobj I noticed there's
no API to extract Major/Minor/Update components conveniently. Currently consumers
do the bit twiddling on their own, but this will change from now on.
I'll convert llvm-objdump (and llvm-readobj) in a later commit.
Differential Revision: http://reviews.llvm.org/D12282
Reviewed by: rafael
llvm-svn: 245938
getSymbolValue now returns a value that in convenient for most callers:
* 0 for undefined
* symbol size for common symbols
* offset/address for symbols the rest
Code that needs something more specific can check getSymbolFlags.
llvm-svn: 241605
At least not in the interface exposed by ObjectFile. This matches what ELF and
COFF implement.
Adjust existing code that was expecting them to have values. No overall
functionality change intended.
Another option would be to change the interface and the ELF and COFF
implementations to say that the value of a common symbol is its size.
llvm-svn: 241593
They are implemented like that in some object formats, but for the interface
provided by lib/Object, SF_Undefined and SF_Common are different things.
This matches the ELF and COFF implementation and fixes llvm-nm for MachO.
llvm-svn: 241587
In these two contexts we really just want the raw n_value. No need to use
getSymbolValue which checks for special cases where, semantically, the symbol
has no value.
llvm-svn: 241584
Originally added in r139314.
Back then it didn't actually get the address, it got whatever value the
relocation used: address or offset.
The values in different object formats are:
* MachO: Always an offset.
* COFF: Always an address, but when talking about the virtual address of
sections it says: "for simplicity, compilers should set this to zero".
* ELF: An offset for .o files and and address for .so files. In the case of the
.so, the relocation in not linked to any section (sh_info is 0). We can't
really compute an offset.
Some API mappings would be:
* Use getAddress for everything. It would be quite cumbersome. To compute the
address elf has to follow sh_info, which can be corrupted and therefore the
method has to return an ErrorOr. The address of the section is also the same
for every relocation in a section, so we shouldn't have to check the error
and fetch the value for every relocation.
* Use a getValue and make it up to the user to know what it is getting.
* Use a getOffset and:
* Assert for dynamic ELF objects. That is a very peculiar case and it is
probably fair to ask any tool that wants to support it to use ELF.h. The
only tool we have that reads those (llvm-readobj) already does that. The
only other use case I can think of is a dynamic linker.
* Check that COFF .obj files have sections with zero virtual address spaces. If
it turns out that some assembler/compiler produces these, we can change
COFFObjectFile::getRelocationOffset to subtract it. Given COFF format,
this can be done without the need for ErrorOr.
The getRelocationAddress method was never implemented for COFF. It also
had exactly one use in a very peculiar case: a shortcut for adding the
section value to a pcrel reloc on MachO.
Given that, I don't expect that there is any use out there of the C API. If
that is not the case, let me know and I will add it back with the implementation
inlined and do a proper deprecation.
llvm-svn: 241450
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 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
On ELF that was already the case since getting the size of a symbol
never fails.
On MachO and COFF we could fail trying to get the section of a symbol. But
we don't really need the section, just the section number to know if two
symbols are in the same section or not.
llvm-svn: 240580
This returns either the symbol offset or address. Since it is not defined which
one, it never has to lookup the section and so never fails.
I will add users in the next commit.
llvm-svn: 240569
COFF and MachO only define symbol sizes for common symbols. Reflect that
in the class hierarchy by having a method for common symbols only in the base
and a general one in ELF.
This avoids the need of using a magic value for the size, which had a few
problems
* Most callers didn't check for it.
* The ones that did could not tell the magic value from a file actually having
that value.
llvm-svn: 240529
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
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
Report proper error code from MachOObjectFile constructor if we
can't parse another segment load command (we already return a proper
error if segment load command contents is suspicious).
llvm-svn: 239109
Summary:
Properly report the error in segment load commands from MachOObjectFile
constructor instead of crashing the program.
Adjust the test case accordingly.
Test Plan: regression test suite
Reviewers: rafael, filcab
Subscribers: llvm-commits
llvm-svn: 239081
Summary:
Currently all load commands are parsed in MachOObjectFile constructor.
If the next load command cannot be parsed, or if command size is too
small, properly report it through the error code and fail to construct
the object, instead of crashing the program.
Test Plan: regression test suite
Reviewers: rafael, filcab
Subscribers: llvm-commits
llvm-svn: 239080
Summary: Instead, properly report this error from MachOObjectFile constructor.
Test Plan: regression test suite
Reviewers: rafael
Subscribers: llvm-commits
llvm-svn: 239078
Summary:
Avoid parsing object file each time MachOObjectFile::getHeader() is
called. Instead, cache the header in MachOObjectFile constructor, where
it's parsed anyway. In future, we must avoid constructing the object
at all if the header can't be parsed.
Test Plan: regression test suite.
Reviewers: rafael
Subscribers: llvm-commits
llvm-svn: 239075
Summary:
Now users don't have to manually deal with getFirstLoadCommandInfo() /
getNextLoadCommandInfo(), calculate the number of load segments, etc.
No functionality change.
Test Plan: regression test suite
Reviewers: rafael, lhames, loladiro
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10144
llvm-svn: 238983
This commit adds partial support for MachO relocations to RelocVisitor.
A simple test case is added to show that relocations are indeed being
applied and that using llvm-dwarfdump on MachO files no longer errors.
Correctness is not yet tested, due to an unrelated bug in DebugInfo,
which will be fixed with appropriate testcase in a followup commit.
Differential Revision: http://reviews.llvm.org/D8148
llvm-svn: 238663
MachO and COFF quite reasonably only define the size for common symbols.
We used to try to figure out the "size" by computing the gap from one symbol to
the next.
This would not be correct in general, since a part of a section can belong to no
visible symbol (padding, private globals).
It was also really expensive, since we would walk every symbol to find the size
of one.
If a caller really wants this, it can sort all the symbols once and get all the
gaps ("size") in O(n log n) instead of O(n^2).
On MachO this also has the advantage of centralizing all the checks for an
invalid n_sect.
llvm-svn: 238028
Summary:
This supersedes http://reviews.llvm.org/D4010, hopefully properly
dealing with the JIT case and also adds an actual test case.
DwarfContext was basically already usable for the JIT (and back when
we were overwriting ELF files it actually worked out of the box by
accident), but in order to resolve relocations correctly it needs
to know the load address of the section.
Rather than trying to get this out of the ObjectFile or requiring
the user to create a new ObjectFile just to get some debug info,
this adds the capability to pass in that info directly.
As part of this I separated out part of the LoadedObjectInfo struct
from RuntimeDyld, since it is now required at a higher layer.
Reviewers: lhames, echristo
Reviewed By: echristo
Subscribers: vtjnash, friss, rafael, llvm-commits
Differential Revision: http://reviews.llvm.org/D6961
llvm-svn: 237961
Summary:
Shift an older “invalid file” test to get a consistent naming for these tests.
Bugs found by afl-fuzz
Reviewers: rafael
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6945
llvm-svn: 226219
be exported from a dylib if their containing object file were linked into one.
No test case: No command line tools query this flag, and there are no Object
unit tests.
llvm-svn: 226217
Summary: This fixes the exports iterator if the export list is empty.
Reviewers: Bigcheese, kledzik
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6732
llvm-svn: 224563
Also corrected the name of the load command to not end in an ’S’ as well as corrected
the name of the MachO::linker_option_command struct and other places that had the
word option as plural which did not match the Mac OS X headers.
llvm-svn: 224485
These methods are only used by MCJIT and are very specific to it. In fact, they
are also fairly specific to the fact that we have a dynamic linker of
relocatable objects.
llvm-svn: 223964
Summary: Add rpath load command support in Mach-O object and update llvm-objdump to use it.
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D6512
llvm-svn: 223343
This CL introduces MachOObjectFile::getUuid(). This function returns an ArrayRef to the object file's UUID, or an empty ArrayRef if the object file doesn't contain an LC_UUID load command.
The new function is gonna be used by llvm-symbolizer.
llvm-svn: 219866
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
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
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
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
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
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
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
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
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
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
so that llvm-size will total up all the sections in the Berkeley format. This
allows for rough categorizations for Mach-O sections. And allows the total of
llvm-size’s Berkeley and System V formats to be the same.
llvm-svn: 209158
SECTDIFF relocations on 32-bit x86.
This fixes several of the MCJIT regression test failures that show up on 32-bit
builds.
<rdar://problem/16886294>
llvm-svn: 208635
This has the following advantages:
* Less code.
* The old ELF implementation was wrong for non-relocatable objects.
* The old ELF implementation (and I think MachO) was wrong for thumb.
No current testcase since this is only used from MCJIT and it only uses
relocatable objects and I don't think it supports thumb yet.
llvm-svn: 205508
This reverts commit r205479.
It turns out that nm does use addresses, it is just that every reasonable
relocatable ELF object has sections with address 0. I have no idea if those
exist in reality, but it at least it shows that llvm-nm should use the name
address.
The added test was includes an unusual .o file with non 0 section addresses. I
created it by hacking ELFObjectWriter.cpp.
Really sorry for the churn.
llvm-svn: 205493
What llvm-nm prints depends on the file format. On ELF for example, if the
file is relocatable, it prints offsets. If it is not, it prints addresses.
Since it doesn't really need to care what it is that it is printing, use the
generic term value.
Fix or implement getSymbolValue to keep llvm-nm working.
llvm-svn: 205479
This adds a second implementation of the AArch64 architecture to LLVM,
accessible in parallel via the "arm64" triple. The plan over the
coming weeks & months is to merge the two into a single backend,
during which time thorough code review should naturally occur.
Everything will be easier with the target in-tree though, hence this
commit.
llvm-svn: 205090
Some targets require more than one relocation entry to perform a relocation.
This change allows processRelocationRef to process more than one relocation
entry at a time by passing the relocation iterator itself instead of just
the relocation entry.
Related to <rdar://problem/16199095>
llvm-svn: 204439
Allow object files to be tagged with a version-min load command for iOS
or MacOSX.
Teach macho-dump to understand the version-min load commands for
testcases.
rdar://11337778
llvm-svn: 204190
Summary:
This adds ObjectFile::section_iterator_range, that allows to write
range-based for-loops running over all sections of a given file.
Several files from lib/ are converted to the new interface. Similar fixes
should be applied to a variety of llvm-* tools.
Reviewers: rafael
Reviewed By: rafael
CC: llvm-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D3069
llvm-svn: 203799
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
This interface allows IRObjectFile to be implemented without having dummy
methods for all section and segment related methods.
Both llvm-ar and llvm-nm are changed to use it. Unfortunately the mangler is
still not plugged in since it requires some refactoring to make a Module hold
a DataLayout.
llvm-svn: 201881
COFF has only one symbol table.
MachO has a LC_DYSYMTAB, but that is not a symbol table, just extra info about
the one symbol table (LC_SYMTAB).
IR (coming soon) also has only one table.
llvm-svn: 200488
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
The constructors of classes deriving from Binary normally take an error_code
as an argument to the constructor. My original intent was to change them
to have a trivial constructor and move the initial parsing logic to a static
method returning an ErrorOr. I changed my mind because:
* A constructor with an error_code out parameter is extremely convenient from
the implementation side. We can incrementally construct the object and give
up when we find an error.
* It is very efficient when constructing on the stack or when there is no
error. The only inefficient case is where heap allocating and an error is
found (we have to free the memory).
The result is that this is a much smaller patch. It just standardizes the
create* helpers to return an ErrorOr.
Almost no functionality change: The only difference is that this found that
we were trying to read past the end of COFF import library but ignoring the
error.
llvm-svn: 199770
Craig Topper