This breaks out some (more) common llvm-specific
variables. Controlling the subprojects and target architectures, along
with clues about restricting build parallelism when linking. 'more
common' is somewhat subjective, of course.
Differential Revision: https://reviews.llvm.org/D105822
The CMake community Wiki has been moved to the [[ https://gitlab.kitware.com/cmake/community/wikis/home | Kitware GitLab Instance ]].
Also, the original anchor for `Information how to set up various cross compiling toolchains` section might not work as expected. The original content is now being collapsed, so browser won't navigate to the right section directly.
Hence, I think it might be better to provide the section name instead of `this section` with link to help readers find the right section by themselves.
Reviewed By: void
Differential Revision: https://reviews.llvm.org/D104996
I found the documentation of the various CMake variables difficult to
navigate, because they are unsorted. I can see they've grown
organically with new clusters of somewhat-related options, but the
result is hard to use. This collates them (treating '_' as space).
Differential Revision: https://reviews.llvm.org/D102481
LLVM_DEFINITIONS is a string variable containing a list of arguments
to pass to the compiler. When CMake's add_definitions is passed a
string variable, this is interpreted as one argument. To make it
behave properly, the string variable needs to be split into a list.
Despite the fact that add_definitions isn't supposed to be used like
the LLVM docs recommended, it worked fine in practice in many cases.
If the first argument in LLVM_DEFINITIONS is of the form -DFOO=42
instead of plain -DFOO, the rest of the string is treated as value
to this define. I.e. if LLVM_DEFINITIONS consists of `-DFOO=42 -DBAR`,
CMake ended up passing `-DFOO="42 -DBAR"` to the compiler.
See https://gitlab.kitware.com/cmake/cmakissues/22162
for discussion on the matter.
Changing LLVM_DEFINITIONS to be a list variable would possibly be
more disruptive; instead keep the variable defined as before but
change the recommendation for how to use it. Then projects using it
can gradually be updated to follow the new recommendation.
Differential Revision: https://reviews.llvm.org/D103044
Beginners might not aware of this variable and wanted to try a new experimental target.
Although this variable mention in Writing a Backend Documentation. But it becomes easy to search when listed in cmake.rst doc where most variables are listed.
Reviewed By: myhsu
Differential Revision: https://reviews.llvm.org/D100729
Allow overriding the default set of flags used to enable UBSan when
building llvm.
This can be used to test new checks or opt out of certain checks.
Differential Revision: https://reviews.llvm.org/D89439
Add `LLVM_EXTERNALIZE_DEBUGINFO` to CMake.rst. This should help make dSYM
generation more discoverable.
Differential Revision: https://reviews.llvm.org/D87591
This patch optionally replaces the CRT allocator (i.e., malloc and free) with rpmalloc (mixed public domain licence/MIT licence) or snmalloc (MIT licence) or mimalloc (MIT licence). Please note that the source code for these allocators must be available outside of LLVM's tree.
To enable, use `cmake ... -DLLVM_INTEGRATED_CRT_ALLOC=D:/git/rpmalloc -DLLVM_USE_CRT_RELEASE=MT` where `D:/git/rpmalloc` has already been git clone'd from `https://github.com/mjansson/rpmalloc`. The same applies to snmalloc and mimalloc.
When enabled, the allocator will be embeded (statically linked) into the LLVM tools & libraries. This currently only works with the static CRT (/MT), although using the dynamic CRT (/MD) could potentially work as well in the future.
When enabled, this changes the memory stack from:
new/delete -> MS VC++ CRT malloc/free -> HeapAlloc -> VirtualAlloc
to:
new/delete -> {rpmalloc|snmalloc|mimalloc} -> VirtualAlloc
The goal of this patch is to bypass the application's global heap - which is thread-safe thus inducing locking - and instead take advantage of a modern lock-free, thread cache, allocator. On a 6-core Xeon Skylake we observe a 2.5x decrease in execution time when linking a large scale application with LLD and ThinLTO (12 min 20 sec -> 5 min 34 sec), when all hardware threads are being used (using LLD's flag /opt:lldltojobs=all). On a dual 36-core Xeon Skylake with all hardware threads used, we observe a 24x decrease in execution time (1 h 2 min -> 2 min 38 sec) when linking a large application with LLD and ThinLTO. Clang build times also see a decrease in the range 5-10% depending on the configuration.
Differential Revision: https://reviews.llvm.org/D71786
Summary:
This patch add the dataflow option to LLVM_USE_SANITIZER and documents
it.
Tested via check-cxx (wip to fix the errors).
Reviewers: morehouse, #libc!
Subscribers: mgorny, cfe-commits, libcxx-commits
Tags: #clang, #libc
Differential Revision: https://reviews.llvm.org/D78390
This handles not paths embedded in debug info, but also in sources.
Since the use of this flag is controlled by an option, rather than
replacing the new option, we add a new option.
Differential Revision: https://reviews.llvm.org/D76018
When LLVM_APPEND_VC_REV=OFF is set, the current git hash is no
longer embedded into binaries (mostly for --version output).
Without it, most binaries need to relink after every single
commit, even if they didn't change otherwise (due to, say,
a documentation-only commit).
LLVM_APPEND_VC_REV is ON by default, so this doesn't change the
default behavior of anything.
With this, all clients of GenerateVersionFromVCS.cmake honor
LLVM_APPEND_VC_REV.
Differential Revision: https://reviews.llvm.org/D72855
Summary: The options aren't supported so they can be removed.
Reviewers: beanz, smeenai, compnerd
Reviewed By: compnerd
Subscribers: mgorny, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69877
This extension point is not needed. Provide the equivalent option
through `CMAKE_CXX_STANDARD` which mirrors the previous extension point. Rely on
CMake to provide the check for the compiler instead.
It is sometimes useful to have the C++ standard library linked into the
assembly when compiling clang, particularly when distributing a compiler
onto systems that don't have a copy of stdlibc++ or libc++ installed.
This functionality should work with either GCC or Clang as the host
compiler, though statically linking libc++ (as may be required for
licensing purposes) is only possible if the host compiler is Clang with
a copy of libc++ available.
Differential Revision: https://reviews.llvm.org/D65603
llvm-svn: 368907
Add user enabled option to create lipo with symlink to llvm-lipo
Used rL326381 for reference.
Differential Revision: https://reviews.llvm.org/D65477
llvm-svn: 367444
The autoconf build system support has been removed a while ago, remove
some outdated references.
Differential Revision: https://reviews.llvm.org/D63608
llvm-svn: 365013
Summary:
This updates all places in documentation that refer to "Mac OS X", "OS X", etc.
to instead use the modern name "macOS" when no specific version number is
mentioned.
If a specific version is mentioned, this attempts to use the OS name at the time
of that version:
* Mac OS X for 10.0 - 10.7
* OS X for 10.8 - 10.11
* macOS for 10.12 - present
Reviewers: JDevlieghere
Subscribers: mgorny, christof, arphaman, cfe-commits, lldb-commits, libcxx-commits, llvm-commits
Tags: #clang, #lldb, #libc, #llvm
Differential Revision: https://reviews.llvm.org/D62654
llvm-svn: 362113
The unwind tables (`.eh_frame`, `.arm.extab`) add a significant chunk of data to
the final binaries. These should not be needed normally, particularly when
exceptions are disabled. This enables shrinking `lldb-server` by ~18% (3 MiB)
when built with gold.
llvm-svn: 359819
Simplify building with particular C++ standards by replacing the
specific "enable standard X" flags with a flag that allows specifying
the standard you want directly.
We preserve compatibility with the existing flags so that anyone with
those flags in existing caches won't break mysteriously.
Differential Revision: https://reviews.llvm.org/D60399
llvm-svn: 357899
Use some of the wording and the motivating example from r344555. The
lack of documentation was pointed out by Roman Lebedev.
Differential Revision: https://reviews.llvm.org/D58286
llvm-svn: 354167
Summary:
The RFC on moving past C++11 got good traction:
http://lists.llvm.org/pipermail/llvm-dev/2019-January/129452.html
This patch therefore bumps the toolchain versions according to our policy:
llvm.org/docs/DeveloperPolicy.html#toolchain
Subscribers: mgorny, jkorous, dexonsmith, llvm-commits, mehdi_amini, jyknight, rsmith, chandlerc, smeenai, hans, reames, lattner, lhames, erichkeane
Differential Revision: https://reviews.llvm.org/D57264
llvm-svn: 353374
Reverting D57264 again, it looks like we're down to two bots that need fixing:
polly-amd64-linux
polly-arm-linux
They both have old versions of libstdc++ and recent clang.
llvm-svn: 352954
Summary:
The RFC on moving past C++11 got good traction:
http://lists.llvm.org/pipermail/llvm-dev/2019-January/129452.html
This patch therefore bumps the toolchain versions according to our policy:
llvm.org/docs/DeveloperPolicy.html#toolchain
Subscribers: mgorny, jkorous, dexonsmith, llvm-commits, mehdi_amini, jyknight, rsmith, chandlerc, smeenai, hans, reames, lattner, lhames, erichkeane
Differential Revision: https://reviews.llvm.org/D57264
llvm-svn: 352951
Summary:
The RFC on moving past C++11 got good traction:
http://lists.llvm.org/pipermail/llvm-dev/2019-January/129452.html
This patch therefore bumps the toolchain versions according to our policy:
llvm.org/docs/DeveloperPolicy.html#toolchain
Subscribers: mgorny, jkorous, dexonsmith, llvm-commits, mehdi_amini, jyknight, rsmith, chandlerc, smeenai, hans, reames, lattner, lhames, erichkeane
Differential Revision: https://reviews.llvm.org/D57264
llvm-svn: 352834
A handful of bots are still breaking, either because I missed them in my audit,
they were offline, or something else. I'm contacting their authors, but I'll
revert for now and re-commit later.
llvm-svn: 352814
Summary:
The RFC on moving past C++11 got good traction:
http://lists.llvm.org/pipermail/llvm-dev/2019-January/129452.html
This patch therefore bumps the toolchain versions according to our policy:
llvm.org/docs/DeveloperPolicy.html#toolchain
Subscribers: mgorny, jkorous, dexonsmith, llvm-commits, mehdi_amini, jyknight, rsmith, chandlerc, smeenai, hans, reames, lattner, lhames, erichkeane
Differential Revision: https://reviews.llvm.org/D57264
llvm-svn: 352811
Summary: This change factors out compiler checking / warning, and documents LLVM_FORCE_USE_OLD_TOOLCHAIN. It doesn't introduce any functional changes nor policy changes, these will come late.
Subscribers: mgorny, jkorous, dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D56799
llvm-svn: 351387
Summary:
This function is very similar to add_llvm_library(), so this patch merges it
into add_llvm_library() and replaces all calls to add_llvm_loadable_module(lib ...)
with add_llvm_library(lib MODULE ...)
Reviewers: philip.pfaffe, beanz, chandlerc
Reviewed By: philip.pfaffe
Subscribers: chapuni, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D51748
llvm-svn: 349839