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
In support of serializing executables, obj2yaml now records the virtual address
and size of sections. It also serializes whatever we strictly need from
the PE header, it expects that it can reconstitute everything else via
inference.
yaml2obj can reconstitute a fully linked executable.
In order to get executables correctly serialized/deserialized, other
bugs were fixed as a circumstance. We now properly respect file and
section alignments. We also avoid writing out string tables unless they
are strictly necessary.
llvm-svn: 221975
Referencing one symbol from another in the same section does not
generally require a relocation. However, the MS linker has a feature
called /INCREMENTAL which enables incremental links. It achieves this
by creating thunks to the actual function and redirecting all
relocations to point to the thunk.
This breaks down with the old scheme if you have a function which
references, say, itself. On x86_64, we would use %rip relative
addressing to reference the start of the function from out current
position. This would lead to miscompiles because other references might
reference the thunk instead, breaking function pointer equality.
This fixes PR21520.
llvm-svn: 221678
The ELF symbol `st_other` field might contain additional flags besides
visibility ones. This patch implements support for some MIPS specific
flags.
llvm-svn: 221491
The getBinary and getBuffer method now return ordinary pointers of appropriate
const-ness. Ownership is transferred by calling takeBinary(), which returns a
pair of the Binary and a MemoryBuffer.
llvm-svn: 221003
Summary: This helps llvm-objdump -r to print out the symbol name along
with the relocation type on x86. Adjust existing tests from checking
for "Unknown" to check for the symbol now.
Test Plan: Adjusted test/Object tests.
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5987
llvm-svn: 220866
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
We, I suppose naïvely, believed the COFF specification with regard to
auxiliary symbol records which defined sections: they specified that the
symbol value should be zero. However, dumpbin and MinGW's objdump do
not consider the symbol value as a restriction. Relaxing this allows us
to properly dump MinGW linked executables.
llvm-svn: 219479
While getSectionContents was updated to do the right thing,
getSectionSize wasn't. Move the logic to getSectionSize and leverage it
from getSectionContents.
llvm-svn: 219391
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
output of the llvm-dwarfdump and llvm-objdump report the endianness
used when the object files were generated.
Patch by Charlie Turner.
llvm-svn: 219110
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
For biendian targets like ARM and AArch64, it is useful to have the
output of the llvm-dwarfdump and llvm-objdump report the endianness
used when the object files were generated.
Patch by Charlie Turner.
llvm-svn: 218408
This change fixes the ARM and AArch64 relocation visitors in
RelocVisitor. They were unconditionally assuming the object data are
little-endian. Tests have been added to ensure that the
llvm-dwarfdump utility does not crash when processing big-endian
object files.
Patch by Charlie Turner.
llvm-svn: 218407
This change replaces the brittle if/else chain of string comparisons
with a switch statement on the detected target triple, removing the
need for testing arbitrary architecture names returned from
getFileFormatName, whose primary purpose seems to be for display
(user-interface) purposes. The visitor now takes a reference to the
object file, rather than its arbitrary file format name to figure out
whether the file is a 32 or 64-bit object file and what the detected
target triple is.
A set of tests have been added to help show that the refactoring processes
relocations for the same targets as the original code.
Patch by Charlie Turner.
llvm-svn: 218406
This reverts commit faac033f7364bb4226e22c8079c221c96af10d02.
The test depends on all targets to be enabled in llc in order to pass,
and needs to be rewritten/refactored to not have that dependency.
llvm-svn: 218393
For biendian targets like ARM and AArch64, it is useful to have the
output of the llvm-dwarfdump and llvm-objdump report the endianness
used when the object files were generated.
Patch by Charlie Turner.
llvm-svn: 218391
This change fixes the ARM and AArch64 relocation visitors in
RelocVisitor. They were unconditionally assuming the object data are
little-endian. Tests have been added to ensure that the
llvm-dwarfdump utility does not crash when processing big-endian
object files.
Patch by Charlie Turner.
llvm-svn: 218389
This change replaces the brittle if/else chain of string comparisons
with a switch statement on the detected target triple, removing the
need for testing arbitrary architecture names returned from
getFileFormatName, whose primary purpose seems to be for display
(user-interface) purposes. The visitor now takes a reference to the
object file, rather than its arbitrary file format name to figure out
whether the file is a 32 or 64-bit object file and what the detected
target triple is.
A set of tests have been added to help show that the refactoring processes
relocations for the same targets as the original code.
Patch by Charlie Turner.
llvm-svn: 218388
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
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
