Commit Graph

25 Commits

Author SHA1 Message Date
Jez Ng 21f831134c [lld-macho] Add very basic support for LTO
Just enough to consume some bitcode files and link them. There's more
to be done around the symbol resolution API and the LTO config, but I don't yet
understand what all the various LTO settings do...

Reviewed By: #lld-macho, compnerd, smeenai, MaskRay

Differential Revision: https://reviews.llvm.org/D90663
2020-11-10 12:19:28 -08:00
Jez Ng 2c2a749448 [lld-macho] Ignore a few more undocumented flags
Reviewed By: #lld-macho, compnerd

Differential Revision: https://reviews.llvm.org/D88268
2020-09-25 11:28:37 -07:00
Jez Ng 98f03908d0 [lld-macho] Support -weak_lx, -weak_library, -weak_framework
They cause their corresponding libraries / frameworks to be loaded via
`LC_LOAD_WEAK_DYLIB` instead of `LC_LOAD_DYLIB`.

Reviewed By: #lld-macho, gkm

Differential Revision: https://reviews.llvm.org/D87929
2020-09-23 19:26:41 -07:00
Jez Ng 79412d6ca7 [lld-macho] Ignore `-mllvm` and its argument
Test Plan:

Reviewed By: #lld-macho, compnerd, MaskRay

Differential Revision: https://reviews.llvm.org/D87803
2020-09-23 19:26:40 -07:00
Greg McGary 8f2c31f22b [lld-macho] handle options -search_paths_first, -search_dylibs_first
Differential Revision: https://reviews.llvm.org/D88054
2020-09-23 14:56:33 -07:00
Greg McGary fa5f945212 [lld-macho] cleanup unimplemented-option warnings
Remove all spurious `HelpHidden` flags from  `lld/MachO/Options.td`. Add test for `HelpHidden` to `warnIfUnimplementedOption()` so that the empty `// handled elsewhere` case is unnecessary.

Reviewed By: #lld-macho, int3, smeenai

Differential Revision: https://reviews.llvm.org/D88160
2020-09-23 14:38:23 -07:00
Greg McGary 145ce86dba [lld-macho] handle option -headerpad_max_install_names
Differential Revision: https://reviews.llvm.org/D88064
2020-09-22 17:24:19 -07:00
Greg McGary 7afbf3192d [lld-macho] minimally handle option -dynamic
Stifle the warning for unimplemented option `-dyamic`, since it is already the default. Add `Config::staticLink` and skeletal support for altering the flag, but otherwise leave the option `-static` as hidden and its warning in place.

Differential Revision: https://reviews.llvm.org/D88045
2020-09-22 08:03:44 -07:00
Jez Ng e48d1262b8 [lld-macho] Support -rpath
Pretty straightforward; just emits LC_RPATH for dyld to consume.

Note that lld itself does not yet support dylib lookup via @rpath.

Reviewed By: #lld-macho, compnerd

Differential Revision: https://reviews.llvm.org/D85701
2020-08-12 19:50:28 -07:00
Greg McGary a379f2c251 [lld-macho] Handle command-line option -sectcreate SEG SECT FILE
Handle command-line option `-sectcreate SEG SECT FILE`, which inputs a binary blob from `FILE` into `SEG,SECT`

Reviewed By: int3

Differential Revision: https://reviews.llvm.org/D85501
2020-08-10 18:47:13 -07:00
Jez Ng 22e6648a18 [lld-macho] Implement -headerpad
Tools like `install_name_tool` and `codesign` may modify the Mach-O
header and increase its size. The linker has to provide padding to make this
possible. This diff does that, plus sets its default value to 32 bytes (which
is what ld64 does).

Unlike ld64, however, we lay out our sections *exactly* `-headerpad` bytes from
the header, whereas ld64 just treats the padding requirement as a lower bound.
ld64 actually starts laying out the non-header sections in the __TEXT segment
from the end of the (page-aligned) segment rather than the front, so its
binaries typically have more than `-headerpad` bytes of actual padding.
We should consider implementing the same alignment behavior.

Reviewed By: #lld-macho, compnerd

Differential Revision: https://reviews.llvm.org/D84714
2020-07-30 14:29:31 -07:00
Jez Ng 06a0dd2467 [lld-macho] Ignore -dependency_info and its argument
XCode passes in this flag, which we do not yet implement. Skip
over the argument for now so we can at least successfully parse the
linker invocation.

Reviewed By: #lld-macho, compnerd

Differential Revision: https://reviews.llvm.org/D84485
2020-07-24 15:55:27 -07:00
Nico Weber 9bcd59fdef fix a typo to cycle bots 2020-06-18 11:31:47 -04:00
Greg McGary 7df80e3f23 [lld-macho] Specify the complete set of command-line options for ld64
This is a complete Options.td compiled from ld(1) dated 2018-03-07 and
cross checked with ld64 source code version 512.4 dated 2018-03-18.

This is the first in a series of diffs for argument handling. Follow-ups
will include switch cases for all the new instances of `OPT_foo`, and
parsing/validation of arguments attached to options, e.g., more code
akin to `OPT_platform_version` and associated `parsePlatformVersion()`.

Reviewed By: smeenai

Differential Revision: https://reviews.llvm.org/D80582
2020-06-15 12:50:20 -07:00
Saleem Abdulrasool 37d93b528c lld: ignore the `-search_paths_first` option on MachO
ld64 provides the `-search_path_firsts` which will search each path in
the library search path order for both `lib[name].dylib`, `lib[name].a`
before moving on (searching all paths for the dylib and then falling
back to the static library if a shared library was not found).

This option has been the default for a long time, but the command line
flag still exists.  Ignore it for compatibility.
2020-06-03 15:36:35 +00:00
Jez Ng 55e9eb416e [lld-macho] Support -order_file
The order file indicates how input sections should be sorted within each
output section, based on the symbols contained within those sections.

This diff sets the stage for implementing and testing
`.subsections_via_symbols`, where we will break up InputSections by each
symbol and sort them more granularly.

Reviewed By: smeenai

Differential Revision: https://reviews.llvm.org/D79668
2020-05-19 07:46:57 -07:00
Nico Weber 759bae956a [lld-macho] Ignore -platform_version and -syslibroot flags.
clang passes these flags; this makes it easier to try `clang -v`
output with `ld -flavor darwinnew`.

Differential Revision: https://reviews.llvm.org/D79797
2020-05-12 19:17:01 -04:00
Jez Ng 87b6fd3e02 [lld-macho] Add support for creating and reading reexported dylibs
This unblocks the linking of real programs, since many core system
functions are only available as sub-libraries of libSystem.

Differential Revision: https://reviews.llvm.org/D79228
2020-05-12 07:52:03 -07:00
Jez Ng 62b8f32f76 [lld-macho][reland] Add support for emitting dylibs with a single symbol
This got reverted due to UBSAN errors in a diff lower in the stack,
which is being fixed in https://reviews.llvm.org/D79050. This diff is
otherwise identical to the original https://reviews.llvm.org/D76908
(which was committed in 9598778bd1 and reverted in b52bc2653b).

Differential Revision: https://reviews.llvm.org/D79051
2020-04-28 17:08:32 -07:00
Shoaib Meenai b52bc2653b Revert "[lld-macho] Add support for emitting dylibs with a single symbol"
This reverts commit 9598778bd1.

Reverting due to UBSan failures:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/40817/steps/check-lld%20ubsan/logs/stdio
2020-04-28 11:34:03 -07:00
Jez Ng 9598778bd1 [lld-macho] Add support for emitting dylibs with a single symbol
Summary:
Add logic for emitting the correct set of load commands and segments
when `-dylib` is passed.

I haven't gotten to implementing a real export trie yet, so we can only
emit a single symbol, but it's enough to replace the YAML test files
introduced in D76252.

Differential Revision: https://reviews.llvm.org/D76908
2020-04-27 13:33:46 -07:00
Jez Ng 060efd24c7 [lld-macho] Add basic support for linking against dylibs
This diff implements:

* dylib loading (much of which is being restored from @pcc and @ruiu's
  original work)
* The GOT_LOAD relocation, which allows us to load non-lazy dylib
  symbols
* Basic bind opcode emission, which tells `dyld` how to populate the GOT

Differential Revision: https://reviews.llvm.org/D76252
2020-04-21 13:43:19 -07:00
Fangrui Song 6acd300375 Reland D75382 "[lld] Initial commit for new Mach-O backend"
With a fix for http://lab.llvm.org:8011/builders/clang-cmake-armv8-lld/builds/3636

Also trims some unneeded dependencies.
2020-04-02 12:03:43 -07:00
Oliver Stannard af39151f3c Revert "[lld] Initial commit for new Mach-O backend"
This is causing buildbot failures on 32-bit hosts, for example:
http://lab.llvm.org:8011/builders/clang-cmake-armv8-lld/builds/3636

This reverts commit 03f43b3aca.
2020-04-02 13:23:30 +01:00
Jez Ng 03f43b3aca [lld] Initial commit for new Mach-O backend
Summary:
This is the first commit for the new Mach-O backend, designed to roughly
follow the architecture of the existing ELF and COFF backends, and
building off work that @ruiu and @pcc did in a branch a while back. Note
that this is a very stripped-down commit with the bare minimum of
functionality for ease of review. We'll be following up with more diffs
soon.

Currently, we're able to generate a simple "Hello World!" executable
that runs on OS X Catalina (and possibly on earlier OS X versions; I
haven't tested them). (This executable can be obtained by compiling
`test/MachO/relocations.s`.) We're mocking out a few load commands to
achieve this -- for example, we can't load dynamic libraries, but
Catalina requires binaries to be linked against `dyld`, so we hardcode
the emission of a `LC_LOAD_DYLIB` command. Other mocked out load
commands include LC_SYMTAB and LC_DYSYMTAB.

Differential Revision: https://reviews.llvm.org/D75382
2020-03-31 11:58:47 -07:00