To facilitate experimentation with LTO we require an ar that supports
LLVM IR, and to a lesser degree also an nm. As a first step always
install llvm-ar and llvm-nm.
Sponsored by: The FreeBSD Foundation
ASAN reports become a lot more useful with llvm-symbolizer in $PATH, and the
build is not much more time-consuming. The added benefit is that the
resulting reports will actually include symbol information; without, thread
trace information includes a bunch of addresses that immediately resolve to
an inline function in
^/contrib/compiler-rt/lib/sanitizer_common/sanitizer_common.h and take a
little more effort to examine.
Reviewed by: emaste
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D20484
Building binaries as PIE allows the executable itself to be loaded at a
random address when ASLR is enabled (not just its shared libraries).
With this change PIE objects have a .pieo extension and INTERNALLIB
libraries libXXX_pie.a.
MK_PIE is disabled for some kerberos5 tools, Clang, and Subversion, as
they explicitly reference .a libraries in their Makefiles. These can
be addressed on an individual basis later. MK_PIE is also disabled for
rtld-elf because it is already position-independent using bespoke
Makefile rules.
Currently only dynamically linked binaries will be built as PIE.
Discussed with: dim
Reviewed by: kib
MFC after: 1 month
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18423
Some options come from static constructors in LLVM libraries and are
automatically added to llvm's usage output. They're not really supposed
to be llvm-objdump options.
Reported by: Fangrui Song in LLVM review D54864
Sponsored by: The FreeBSD Foundation
Some options appear in llvm-objdump's usage information as a side effect
of its option parsing implementation and are not actually llvm-objdump
options. Reported in LLVM review https://reviews.llvm.org/D54864.
Reported by: Fangrui Song
Sponsored by: The FreeBSD Foundation
Based on llvm-objdump's online documentation and usage information.
This serves as a starting point; additional detail and cleanup still
required.
Also being submitted upstream in LLVM review D54864. I expect to use
this bespoke copy while we have LLVM 6.0 or 7.0 in FreeBSD; when we
update to LLVM 8.0 it should be upstream and we will switch to it.
PR: 233437
Reviewed by: bcr (man formatting)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18309
llvm-profdata is used with llvm-cov for code coverage (although llvm-cov
can also operate independently in a gcov-compatible mode).
Although llvm-profdata can be used independently of llvm-cov it makes
sense to group these under one option.
Also handle these in OptionalObsoleteFiles.inc while here.
Sponsored by: The FreeBSD Foundation
llvm-cov provides a gcov-compatible interface when invoked as gcov.
Reviewed by: dim, markj
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D17923
The current kernel ifunc implementation creates a PLT entry for each
ifunc definition. ifunc calls therefore consist of a call to the
PLT entry followed by an indirect jump. The jump target is written
during boot when the kernel linker resolves R_[*]_IRELATIVE relocations.
This implementation is defined by requirements for userland code, where
text relocations are avoided. This requirement is not present for the
kernel, so the implementation has avoidable overhead (namely, an extra
indirect jump per call).
Address this for now by adding a special option to the static linker
to inhibit PLT creation for ifuncs. Instead, relocations to ifunc call
sites are passed through to the output file, so the kernel linker can
enumerate such call sites and apply PC-relative relocations directly
to the text section. Thus the overhead of an ifunc call becomes exactly
the same as that of an ordinary function call. This option is only for
use by the kernel and will not work for regular programs.
The final form of this optimization is up for debate; for now, this
change is simple and static enough to be acceptable as an interim
solution.
Reviewed by: emaste
Discussed with: arichardson, dim
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D16748
LLD_BOOTSTRAP (build) is independent of LLD_IS_LD (installed) so they
should not be based on each other.
This is related to upcoming WITH_SYSTEM_LINKER work.
Reviewed by: emaste
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D15836
Introduce WITH_/WITHOUT_LLVM_COV to match GCC's WITH_/WITHOUT_GCOV.
It is intended to provide a superset of the interface and functionality
of gcov.
It is enabled by default when building Clang, similarly to gcov and GCC.
This change moves one file in libllvm to be compiled unconditionally.
Previously it was included only when WITH_CLANG_EXTRAS was set, but the
complexity of a new special case for (CLANG_EXTRAS | LLVM_COV) is not
worth avoiding a tiny increase in build time.
Reviewed by: dim, imp
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D142645
Upstream lld has no man page. Introduce a basic one for FreeBSD based on
ld.lld --help, with a brief introduction and additional detail for some
options.
We'll continue refining this in FreeBSD, and then submit it upstream once
the first round of edits are complete.
Submitted by: krion, Arshan Khanifar, emaste, bjk
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D13813
- Include debug symbols in static libraries. This permits binaries
to include debug symbols for functions obtained from static libraries.
- Permit the C/C++ compiler flags added for MK_DEBUG_FILES to be
overridden by setting DEBUG_FILES_CFLAGS. Use this to limit the debug
information for llvm libraries and binaries.
Reviewed by: emaste
Sponsored by: DARPA / AFRL
Differential Revision: https://reviews.freebsd.org/D12025
invoked as llvm-ranlib, it can create an archive symbol table for
archives of objects compiled for LTO by an LLVM compiler.
Submitted by: Dan McGregor <danismostlikely@gmail.com>
MFC after: 3 days
Move llvm-objdump from CLANG_EXTRAS to installed by default
We currently install three tools from binutils 2.17.50: as, ld, and
objdump. Work is underway to migrate to a permissively-licensed
tool-chain, with one goal being the retirement of binutils 2.17.50.
LLVM's llvm-objdump is intended to be compatible with GNU objdump
although it is currently missing some options and may have formatting
differences. Enable it by default for testing and further investigation.
It may later be changed to install as /usr/bin/objdump, it becomes a
fully viable replacement.
Reviewed by: emaste
Differential Revision: https://reviews.freebsd.org/D8879
We currently install three tools from binutils 2.17.50: as, ld, and
objdump. Work is underway to migrate to a permissively-licensed
tool-chain, with one goal being the retirement of binutils 2.17.50.
LLVM's llvm-objdump is intended to be compatible with GNU objdump
although it is currently missing some options and may have formatting
differences. Enable it by default for testing and further investigation.
It may later be changed to install as /usr/bin/objdump, it becomes a
fully viable replacement.
Reviewed by: emaste
Differential Revision: https://reviews.freebsd.org/D8879
During the upgrade of clang/llvm etc to 3.9.0 in r309124, the PACKAGE
directive in the usr.bin/clang/*.mk files got dropped accidentally.
Restore it, with a few minor changes and additions:
* Correct license in clang.ucl to NCSA
* Add PACKAGE=clang for clang and most of the "ll" tools
* Put lldb in its own package
* Put lld in its own package
Reviewed by: gjb, jmallett
X-MFC-With: 309124
Differential Revision: https://reviews.freebsd.org/D8666
If set it installs LLD as /usr/bin/ld. LLD (as of version 3.9) is not
capable of linking the world and kernel, but can self-host and link many
substantial applications. GNU ld continues to be used for the world and
kernel build, regardless of how this knob is set.
It is on by default for arm64, and off for all other CPU architectures.
Sponsored by: The FreeBSD Foundation
Use this to control inclusion of the libllvm functionality required
by lld. Enable by default on arm64 and amd64, the two platforms where
lld is most usable for testing.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D7713
* Bootstrap llvm-tblgen and clang-tblgen with a minimal llvm static
library, that has no other dependencies.
* Roll up all separate llvm libraries into one big static libllvm.
* Similar for all separate clang and lldb static libraries.
* For all these libraries, generate their .inc files only once.
* Link all llvm tools (including extra) against the big libllvm.
* Link clang and clang-format against the big libllvm and libclang.
* Link lldb against the big libllvm, libclang and liblldb.
N.B.: This is work in progress, some details may still be missing.
It also heavily depends on bsd.*.mk's support for SRCS and DPSRCS with
relative pathnames, which apparently does not always work as expected.
For building llvm, clang and lldb though, it seems to work just fine.
The main idea behind this restructuring is maintainability and build
peformance. The previous large number of very small libraries, each
with their own generated files and dependencies was slow to traverse
and hard to understand.
Possible future improvements:
* Only build certain targets, e.g. for most regular users having just
one target will be fine. This will shave off some build time.
* Building the big llvm, clang and lldb libraries as shared (private)
libraries.
* Adding other components from the LLVM project, such as lld.