Clang integrated assembler was unable to build libunwind PPC32 assembly code,
present in functions used to save/restore register context.
This change consists in replacing the assembly style used in libunwind source,
to one that is compatible with both Clang integrated assembler as well as
GNU assembler.
Patch by Leandro Lupori!
Differential Revision: https://reviews.llvm.org/D61792
llvm-svn: 360862
This change makes each unwind step inspect the instruction at the
return address and, if needed, read r2 from its saved location and
modify the context appropriately.
The unwind logic is able to handle both ELFv1 and ELFv2 stacks.
Reported by Bug 41050
Patch by Leandro Lupori!
Differential Revision: https://reviews.llvm.org/D59694
llvm-svn: 360861
calls into the pthread library use weak symbols.
This option allows libpthread to be a weak dependency rather
than a hard one.
Differential Revision: https://reviews.llvm.org/D60285
llvm-svn: 360610
This change introduces support for building libuwind. The library
build should be complete, but not all CMake options have been
replicated in GN. We also don't support tests yet.
We only support two stage build at the moment.
Differential Revision: https://reviews.llvm.org/D60370
llvm-svn: 359804
For builds with SJLJ, there is no __unw_getcontext symbol. On Windows,
the weak alias macro also expands to a dllexport directive, which fails
if the symbol doesn't exist.
Differential Revision: https://reviews.llvm.org/D60251
llvm-svn: 357711
This is not necessary for ELF since .globl and .weak are mutually
exclusive, but is necessary for Mach-O otherwise the symbol isn't
visible externally.
Differential Revision: https://reviews.llvm.org/D60245
llvm-svn: 357671
libunwind defines the _Unwind_* ABI used by libc++abi. This ABI is a
stable quasi-standard common between multiple implementations such as
LLVM and GNU. The _U* symbol name space is also safely within the symbol
name space that standard C & C++ reserve for the implementation.
Futhermore, libunwind also defines several unw_* symbols, and references
these from the _Unwind_* entry points so the standard/reserved part of
the ABI is dependent on the unw_* part of the ABI. This is not OK for a
C or C++ implementation. The unw_* symbols are reserved for C and extern
"C" used by application code.
This change renames each unw_* function to __unw* and adds a weak alias
unw_* to keep the public <libunwind.h> ABI unchanged for backwards
compatibility. Every reference to unw_* in the implementation has been
changed to use __unw* so that if other unw_* definitions are in force
because nothing uses <libunwind.h> in a particular program, no _Unwind*
code path depends on any unw_* symbol. Furthemore, __unw_* symbols are
hidden, which saves PLT overhead in the shared library case.
In the future, we should cconsider untangling the unw_* API/ABI from the
_Unwind_* API/ABI. The internal API backing the _Unwind_* ABI
implementation should not rely on any nonstandard symbols not in the
implementation-reserved name space. This would then allow separating the
_Unwind_* API/ABI from unw_* entirely, but that's a more substantial
change that's going to require more significant refactoring.
Differential Revision: https://reviews.llvm.org/D59921
llvm-svn: 357640
This change is a consequence of the discussion in "RFC: Place libs in
Clang-dedicated directories", specifically the suggestion that
libunwind, libc++abi and libc++ shouldn't be using Clang resource
directory. Tools like clangd make this assumption, but this is
currently not true for the LLVM_ENABLE_PER_TARGET_RUNTIME_DIR build.
This change addresses that by moving the output of these libraries to
lib/<target> and include/ directories, leaving resource directory only
for compiler-rt runtimes and Clang builtin headers.
Differential Revision: https://reviews.llvm.org/D59013
llvm-svn: 355665
If we're not in a standalone build, this variable should be already
set, so there's no need to set it again or to cache it.
Differential Revision: https://reviews.llvm.org/D57993
llvm-svn: 353915
We're building tests with -nostdlib which means that we need to
explicitly include the builtins library. When using libgcc (default)
we can simply include -lgcc_s on the link line, but when using
compiler-rt builtins we need a complete path to the builtins library.
This path is already available in CMake as <PROJECT>_BUILTINS_LIBRARY,
so we just need to pass that path to lit and if config.compiler_rt is
true, link it to the test.
Prior to this patch, running tests when compiler-rt is being used as
the builtins library was broken as all tests would fail to link, but
with this change running tests when compiler-rt bultins library is
being used should be supported.
Differential Revision: https://reviews.llvm.org/D56701
llvm-svn: 353208
There are several changes:
- Don't stringify Pythonized bools (that's why we're Pythonizing them)
- Support specifying target and sysroot via CMake variables
- Use consistent spelling for --target, --sysroot, --gcc-toolchain
llvm-svn: 353137
CMake has a standard way of setting target triple, sysroot and external
toolchain through CMAKE_<LANG>_COMPILER_TARGET, CMAKE_SYSROOT and
CMAKE_<LANG>_COMPILER_EXTERNAL_TOOLCHAIN. These are turned into
corresponding --target=, --sysroot= and --gcc-toolchain= variables add
included appended to CMAKE_<LANG>_FLAGS.
libunwind, libc++abi, libc++ provides their own mechanism through
<PROJECT>_TARGET_TRIPLE, <PROJECT>_SYSROOT and <PROJECT>_GCC_TOOLCHAIN
variables. These are also passed to lit via lit.site.cfg, and lit config
uses these to set the corresponding compiler flags when building tessts.
This means that there are two different ways of setting target, sysroot
and toolchain, but only one is properly supported in lit. This change
extends CMake build for libunwind, libc++abi and libc++ to also support
the CMake variables in addition to project specific ones in lit.
Differential Revision: https://reviews.llvm.org/D57670
llvm-svn: 353084
While Clang automatically generates the code for placement new,
g++ doesn't do that so we need to provide our own definition.
Differential Revision: https://reviews.llvm.org/D57455
llvm-svn: 352966
This is unfinished, unused and incomplete. This could be brought back in
the future if there's a desire to build a more complete implementation,
but at the moment it's just bitrotting.
Differential Revision: https://reviews.llvm.org/D57252
llvm-svn: 352965
When linking library dependencies, we shouldn't need to export linked
libraries to dependents. We should be explicit about this in
target_link_libraries, otherwise other targets that depend on these such
as sanitizers get repeated (and possibly even conflicting) dependencies.
Differential Revision: https://reviews.llvm.org/D57456
llvm-svn: 352688
When linking library dependencies, we shouldn't need to export linked
libraries to dependents. We should be explicit about this in
target_link_libraries, otherwise other targets that depend on these such
as sanitizers get repeated (and possibly even conflicting) dependencies.
Differential Revision: https://reviews.llvm.org/D57456
llvm-svn: 352654
This is useful when the static libunwind library is being linked into
shared libraries that may be used in with other shared libraries that
use different unwinder. We want to avoid avoid exporting libunwind
symbols in those cases. This achieved by a new CMake option which can be
enabled by libunwind vendors as needed.
The same CMake option has already been added to libc++ and libc++abi in
D55404 and D56026.
Differential Revision: https://reviews.llvm.org/D57107
llvm-svn: 352559
We haven't eliminated C++ library dependency altogether in D57251,
UnwindCursor.hpp had an unused dependency on <algorithm> which was
pulling in other C++ headers. Removing that dependency also revealed
(correctly) that we need our own global placement new declaration. Now
libunwind should be independent of the C++ library.
Differential Revision: https://reviews.llvm.org/D57262
llvm-svn: 352553
This fixes most references to the paths:
llvm.org/svn/
llvm.org/git/
llvm.org/viewvc/
github.com/llvm-mirror/
github.com/llvm-project/
reviews.llvm.org/diffusion/
to instead point to https://github.com/llvm/llvm-project.
This is *not* a trivial substitution, because additionally, all the
checkout instructions had to be migrated to instruct users on how to
use the monorepo layout, setting LLVM_ENABLE_PROJECTS instead of
checking out various projects into various subdirectories.
I've attempted to not change any scripts here, only documentation. The
scripts will have to be addressed separately.
Additionally, I've deleted one document which appeared to be outdated
and unneeded:
lldb/docs/building-with-debug-llvm.txt
Differential Revision: https://reviews.llvm.org/D57330
llvm-svn: 352514
The existing typedef of unw_fpreg_t to uint64_t might work and be
correct for the ARM_EHABI case, but for dwarf, some cases in e.g.
DwarfInstructions.hpp convert between double and unw_fpreg_t.
When converting implicitly between double and unw_fpreg_t (uint64_t),
the values get interpreted as integers and converted to float and vice
versa, while the correct thing would be to keep the same bit pattern.
Avoid the whole issue by using the same definition of unw_fpreg_t
as all other architectures, when using dwarf unwinding on ARM.
Change assembler functions to take a void pointer instead of
unw_fpreg_t pointer, to avoid having a different mangled symbol name
depending on the actual value of this typedef.
Differential Revision: https://reviews.llvm.org/D57001
llvm-svn: 352461
We haven't eliminated C++ library dependency altogether in D57251,
UnwindCursor.hpp had an unused dependency on <algorithm> which was
pulling in other C++ headers. Removing that dependency also revealed
(correctly) that we need our own global placement new declaration. Now
libunwind should be independent of the C++ library.
Differential Revision: https://reviews.llvm.org/D57262
llvm-svn: 352384
The check_library_exists CMake uses a custom symbol definition. This
is a problem when checking for C library symbols because Clang
recognizes many of them as builtins, and returns the
-Wbuiltin-requires-header (or -Wincompatible-library-redeclaration)
error. When building with -Werror which is the default, this causes
the check_library_exists check fail making the build think that C
library isn't available.
To avoid this issue, we should use a symbol that isn't recognized by
Clang and wouldn't cause the same issue. __libc_start_main seems like
reasonable choice that fits the bill.
Differential Revision: https://reviews.llvm.org/D57142
llvm-svn: 352341
The rest of libunwind already uses placement new, these are the only
places where non-placement new is being used introducing undesirable
C++ library dependency.
Differential Revision: https://reviews.llvm.org/D57251
llvm-svn: 352245
Recent Linux kernel release has introduced a bug as part of the ORC
rollout where the vDSO has a valid .eh_frame section, but it's missing
the .eh_frame_hdr section and GNU_EH_FRAME segment has zero size. This
causes libunwind to abort which breaks programs that use libunwind.
The other unwinder implementation (libgcc, non-gnu) instead silently
bail out unless being compiled as debug. This change modifies libunwind
to use the same strategy.
Differential Revision: https://reviews.llvm.org/D57081
llvm-svn: 352016
Either adjust the format string to use a more exact type, or add casts
(for cases when printing pointers to structs/objects with a %p
format specifier).
Differential Revision: https://reviews.llvm.org/D56982
llvm-svn: 351876
When built within the llvm runtimes directory, the runtimes
CMakeLists.txt adds the same.
Differential Revision: https://reviews.llvm.org/D56981
llvm-svn: 351875
all missed!
Thanks to Alex Bradbury for pointing this out, and the fact that I never
added the intended `legacy` anchor to the developer policy. Add that
anchor too. With hope, this will cause the links to all resolve
successfully.
llvm-svn: 351731
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351648
This installs the new developer policy and moves all of the license
files across all LLVM projects in the monorepo to the new license
structure. The remaining projects will be moved independently.
Note that I've left odd formatting and other idiosyncracies of the
legacy license structure text alone to make the diff easier to read.
Critically, note that we do not in any case *remove* the old license
notice or terms, as that remains necessary until we finish the
relicensing process.
I've updated a few license files that refer to the LLVM license to
instead simply refer generically to whatever license the LLVM project is
under, basically trying to minimize confusion.
This is really the culmination of so many people. Chris led the
community discussions, drafted the policy update and organized the
multi-year string of meeting between lawyers across the community to
figure out the strategy. Numerous lawyers at companies in the community
spent their time figuring out initial answers, and then the Foundation's
lawyer Heather Meeker has done *so* much to help refine and get us ready
here. I could keep going on, but I just want to make sure everyone
realizes what a huge community effort this has been from the begining.
Differential Revision: https://reviews.llvm.org/D56897
llvm-svn: 351631
GCC and Clang in MinGW mode don't support __declspec(thread), which
after expanding macros ends up as __attribute__((thread)). Use the
GCC specific attribute __thread instead (the next one in the chain
of alternatives).
Differential Revision: https://reviews.llvm.org/D56905
llvm-svn: 351587
Summary:
Adds the register class implementation for Sparc.
Adds support for DW_CFA_GNU_window_save.
Adds save and restore context functionality.
Adds getArch() function to each Registers_ class to be able to separate
between DW_CFA_AARCH64_negate_ra_state and DW_CFA_GNU_window_save which
are both represented by the same constant.
On Sparc the return address is the address of the call instruction, so
an offset needs to be added when returning to skip the call instruction
and its delay slot. If the function returns a struct it is also necessary
to skip one extra instruction on Sparc V8.
Reviewers: jyknight, mclow.lists, mstorsjo, compnerd
Reviewed By: jyknight, compnerd
Subscribers: jgorbe, mgorny, christof, llvm-commits, fedor.sergeev, JDevlieghere, ldionne, libcxx-commits
Differential Revision: https://reviews.llvm.org/D55763
llvm-svn: 351044
Summary:
Adds the register class implementation for Sparc.
Adds support for DW_CFA_GNU_window_save.
Adds save and restore context functionality.
On Sparc the return address is the address of the call instruction,
so an offset needs to be added when returning to skip the call instruction
and its delay slot. If the function returns a struct it is also necessary
to skip one extra instruction.
Reviewers: jyknight, mclow.lists, mstorsjo, compnerd
Reviewed By: compnerd
Subscribers: fedor.sergeev, JDevlieghere, ldionne, libcxx-commits
Differential Revision: https://reviews.llvm.org/D55763
llvm-svn: 350705
Martin Storsjo