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 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
The -print-file-name option in llvm-nm is to precede each symbol
with the object file it came from. While code for the parsing of this
option and its aliases existed there was no code to implement it.
llvm-svn: 213906
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
the specified section. This is same functionality as darwin’s nm(1) "-s" flag.
There is one FIXME in the code and I’m all ears to anyone that can help me
with that. This option takes exactly two strings and should be allowed
anywhere on the command line. Such that "llvm-nm -s __TEXT __text foo.o"
would work. But that does not as the CommandLine Library does not have a
way to make this work as far as I can tell. For now the "-s __TEXT __text"
has to be last on the command line.
llvm-svn: 212842
This will allow the "-s" flag to implemented in the future as it
is in darwin’s nm(1) to list symbols only in the specified section.
Given a LGTM by Shankar Easwaran who originally implemented
the support for lvm-nm’s -print-armap and archive map symbols.
llvm-svn: 212576
symbol’s name. On darwin the -j flag is used (often in combinations
with other flags) to produce a complete list of symbol names which
than can then be reorder and used with ld(1)’s -order_file.
llvm-svn: 212294
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
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
to match llvm-size and other UNIX systems for their nm(1).
Tweak test cases that used llvm-nm with standard input to add a "-" to
indicate that and add a test case to check the default of a.out for llvm-nm.
llvm-svn: 211529
the tool is given multiple files. Also fix the same issue with Mach-O
universal files. And fix the newline spacing to separate the output
in these cases.
llvm-svn: 211405
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
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
This patch changes GlobalAlias to point to an arbitrary ConstantExpr and it is
up to MC (or the system assembler) to decide if that expression is valid or not.
This reduces our ability to diagnose invalid uses and how early we can spot
them, but it also lets us do things like
@test5 = alias inttoptr(i32 sub (i32 ptrtoint (i32* @test2 to i32),
i32 ptrtoint (i32* @bar to i32)) to i32*)
An important implication of this patch is that the notion of aliased global
doesn't exist any more. The alias has to encode the information needed to
access it in its metadata (linkage, visibility, type, etc).
Another consequence to notice is that getSection has to return a "const char *".
It could return a NullTerminatedStringRef if there was such a thing, but when
that was proposed the decision was to just uses "const char*" for that.
llvm-svn: 210062
The implementation might be better to have a method is64Bit() in the class
SymbolicFile instead of having the static routine isSymbolList64Bit() in
llvm-nm.cpp . But this is very much in the sprit of isObject() and
getNMTypeChar() in llvm-nm.cpp that has a series of if else statements
based on the specific class of the SymbolicFile. I can update this if
folks would like.
Also the tests were updated to be explicit about checking the address for
64-bits or 32-bits from object files.
llvm-svn: 208463
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
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
Microsoft PE/COFF Spec clearly states that the field is of signed interger
type. However, in reality, it's unsigned. If cl.exe needs to create a large
number of sections for COMDAT sections, it will just create more than 32768
sections. Handling large section number as negative number is not correct.
I think this is a spec bug.
Differential Revision: http://llvm-reviews.chandlerc.com/D3088
llvm-svn: 203986
David Majnemer