Summary:
Any invocation of `clang -fuse-ld=lld` that results in a link command
on a macOS host currently fails, because the Darwin lld driver does not
recognize the `-lto_library` option that Clang passes it. Fix the error
by having the Darwin driver ignore the option.
The Clang driver's macOS toolchain is written such that it will always
pass the `-lto_library` option to the linker invocation on a macOS host.
And although the DarwinLdDriver is written to ignore any unknown arguments,
because `-lto_library` begins with `-l`, the DarwinLdDriver interprets it
as a library search command, for a library named "to_library". When the
DarwinLdDriver is unable to find a library specified via `-l`, it exits
with a hard error. This causes any invocation of `clang -fuse-ld=lld`
that results in a link command on a macOS host to fail with an error.
To fix the issue, I considered two alternatives:
1. Modify the Clang Darwin toolchain to only pass `-lto_library` if lld
is *not* being used. lld doesn't support LTO on Darwin anyway, so it
can't use the option. However, I opted against this because, if and
when lld *does* support LTO on Darwin, I'll have to make another
commit to Clang in order to get it to pass the option to lld again.
2. Modify the Darwin lld driver to ignore the `-lto_library` option.
Just in case users may take this to mean LTO is supported, I also
added a warning. If and when lld supports LTO on Darwin, the same
commit that adds support for this option can remove the warning.
Option (2) seemed better to me, and is the rationale behind this commit.
Test Plan: check-lld
Reviewers: ruiu, smeenai, pcc
Reviewed By: smeenai
Subscribers: JDevlieghere, pcc, mehdi_amini, inglorion, steven_wu, llvm-commits
Differential Revision: https://reviews.llvm.org/D47994
llvm-svn: 334641
loadFile could load mulitple files just because yaml has a feature for
putting multiple documents in one file.
Designing a linker around what yaml can do seems like a bad idea to
me. This patch changes it to read a single file.
There are further improvements to be done to the api and they
will follow shortly.
llvm-svn: 235724
All architecture specific handling is now done in the appropriate
ArchHandler subclass.
The StubsPass and GOTPass have been simplified. All architecture specific
variations in stubs are now encoded in a table which is vended by the
current ArchHandler.
llvm-svn: 213187
This is first step in reworking how mach-o relocations are processed.
The existing KindHandler is going to become a delgate/helper object for
processing architecture specific references. The KindHandler knows how
to convert mach-o relocations into References and back, as well, as fixing
up the content the relocation is on.
One of the messy things about mach-o relocations is that they sometime
come in pairs, but the pairs still convert to one lld::Reference. So, the
conversion has to detect pairs (arch specific) and change the stride.
llvm-svn: 211921
The main goal of this patch is to allow "mach-o encoded as yaml" and "native
encoded as yaml" documents to be intermixed. They are distinguished via
yaml tags at the start of the document. This will enable all mach-o test cases
to be written using yaml instead of checking in object files.
The Registry was extend to allow yaml tag handlers to be registered. The
mach-o Reader adds a yaml tag handler for the tag "!mach-o".
Additionally, this patch fixes some buffer ownership issues. When parsing
mach-o binaries, the mach-o atoms can have pointers back into the memory
mapped .o file. But with yaml encoded mach-o, name and content are ephemeral,
so a copyRefs parameter was added to cause the mach-o atoms to make their
own copy.
llvm-svn: 198986
The main changes are in:
include/lld/Core/Reference.h
include/lld/ReaderWriter/Reader.h
Everything else is details to support the main change.
1) Registration based Readers
Previously, lld had a tangled interdependency with all the Readers. It would
have been impossible to make a streamlined linker (say for a JIT) which
just supported one file format and one architecture (no yaml, no archives, etc).
The old model also required a LinkingContext to read an object file, which
would have made .o inspection tools awkward.
The new model is that there is a global Registry object. You programmatically
register the Readers you want with the registry object. Whenever you need to
read/parse a file, you ask the registry to do it, and the registry tries each
registered reader.
For ease of use with the existing lld code base, there is one Registry
object inside the LinkingContext object.
2) Changing kind value to be a tuple
Beside Readers, the registry also keeps track of the mapping for Reference
Kind values to and from strings. Along with that, this patch also fixes
an ambiguity with the previous Reference::Kind values. The problem was that
we wanted to reuse existing relocation type values as Reference::Kind values.
But then how can the YAML write know how to convert a value to a string? The
fix is to change the 32-bit Reference::Kind into a tuple with an 8-bit namespace
(e.g. ELF, COFFF, etc), an 8-bit architecture (e.g. x86_64, PowerPC, etc), and
a 16-bit value. This tuple system allows conversion to and from strings with
no ambiguities.
llvm-svn: 197727
This patch adds support for converting normalized mach-o to and from binary
mach-o. It also changes WriterMachO (which previously directly wrote a
mach-o binary given a set of Atoms) to instead do it in two steps. The first
step uses normalizedFromAtoms() to convert Atoms to normalized mach-o, and the
second step uses writeBinary() which to generate the mach-o binary file.
llvm-svn: 194167
Disable tests to be run with REQUIRES: disable. Note disable is not added to the
config by the test runner Mkaefiles, so essentially disables the test.
Code changes would be required to fix these tests :-
test/darwin/hello-world.objtxt
test/elf/check.test
test/elf/phdr.test
test/elf/ppc.test
test/elf/undef-from-main-dso.test
test/elf/X86_64/note-sections-ro_plus_rw.test
test/pecoff/alignment.test
test/pecoff/base-reloc.test
test/pecoff/bss-section.test
test/pecoff/drectve.test
test/pecoff/dynamic.test
test/pecoff/dynamicbase.test
test/pecoff/entry.test
test/pecoff/hello.test
test/pecoff/imagebase.test
test/pecoff/importlib.test
test/pecoff/lib.test
test/pecoff/multi.test
test/pecoff/reloc.test
test/pecoff/weak-external.test
llvm-svn: 193300
The major changes are:
1) LinkerOptions has been merged into TargetInfo
2) LinkerInvocation has been merged into Driver
3) Drivers no longer convert arguments into an intermediate (core) argument
list, but instead create a TargetInfo object and call setter methods on
it. This is only how in-process linking would work. That is, you can
programmatically set up a TargetInfo object which controls the linking.
4) Lots of tweaks to test suite to work with driver changes
5) Add the DarwinDriver
6) I heavily doxygen commented TargetInfo.h
Things to do after this patch is committed:
a) Consider renaming TargetInfo, given its new roll.
b) Consider pulling the list of input files out of TargetInfo. This will
enable in-process clients to create one TargetInfo the re-use it with
different input file lists.
c) Work out a way for Drivers to format the warnings and error done in
core linking.
llvm-svn: 178776
Add SharedLibraryFile and ArchiveLibraryFile subclasses of File.
Add command line options to lld-core to set various ResolverOptions settings
and added lots of test cases to verify the options work.
llvm-svn: 155183
a hello world executable from atoms. There is still much to be flushed out.
Added one test case, test/darwin/hello-world.objtxt, which exercises the
darwin platform.
Added -platform option to lld-core tool to dynamically select platform.
llvm-svn: 154242
Brian Gesiak