This patch removes the ability to build the runtimes in the 32 bit
multilib configuration, i.e. using -m32. Instead of doing this, one
should cross-compile the runtimes for the appropriate target triple,
like we do for all other triples.
As it stands, -m32 has several issues, which all seem to be related to
the fact that it's not well supported by the operating systems that
libc++ support. The simplest path towards fixing this is to remove
support for the configuration, which is also the best course of action
if there is little interest for keeping that configuration. If there
is a desire to keep this configuration around, we'll need to do some
work to figure out the underlying issues and fix them.
Differential Revision: https://reviews.llvm.org/D114473
When unwind step reaches the end of the stack that means the force unwind should notify the stop function.
This is not an error, it could mean just the thread is cleaned up completely.
Reviewed By: #libunwind, mstorsjo
Differential Revision: https://reviews.llvm.org/D109856
When testing with sanitizers enabled, we need to link against a plethora
of system libraries. Using `-nodefaultlibs` like we used to breaks this,
and we would have to add all these system libraries manually, which is
not portable and error prone. Instead, stop using `-nodefaultlibs` so
that we get the libraries added by default by the compiler.
The only caveat with this approach is that we are now relying on the
fact that `-L <path-to-local-libunwind>` will cause the just built
libunwind to be selected before the system implementation (either of
libunwind or libgcc_s.so), which is somewhat fragile.
This patch also turns the 32 bit multilib build into a soft failure
since we are in the process of removing it anyway, see D114473 for
details. This patch is incompatible with the 32 bit multilib build
because Ubuntu does not provide a proper libstdc++ for 32 bits, and
that is required when running with sanitizers enabled.
Differential Revision: https://reviews.llvm.org/D114385
The libgcc runtime library provides __register_frame and
__deregister_frame functions, which can be used by dynamic code
generators to register an .eh_frame section, which contains one or
more Call Frame Information records, each consisting of a Common
Information Entry record followed by one or more Frame Description
Entry records. This libunwind library also provides __register_frame
and __deregister_frame functions, but they are aliases for
__unw_add_dynamic_fde and __unw_remove_dynamic_fde and thus can only
take a single FDE.
This patch adds __unw_add_dynamic_eh_frame_section and
__unw_remove_dynamic_eh_frame_section functions which explicitly use
the .eh_frame format. Clients such as the ORCv2 platform and runtime
can check for these functions and use them if unwinding is being
provided by libunwind, or fall back to __register_frame and
__deregister_frame if unwinding is provided by libgcc.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D111863
Summary:
This patch marks libunwind test case signal_frame.pass.cpp as UNSUPPORTED on AIX because the AIX assembler does not support CFI directives.
Reviewed by: danielkiss, MaskRay, ldionne, libunwind
Differential Revision: https://reviews.llvm.org/D113607
We've stopped doing it in libc++ for a while now because these names
would end up rotting as we move things around and copy/paste stuff.
This cleans up all the existing files so as to stop the spreading
as people copy-paste headers around.
If Clang is set up to link directly against libunwind (via the
--unwindlib option, or the corresponding builtin default option),
configuring libunwind will fail while bootstrapping (before the
initial libunwind is built), because every cmake test will
fail due to -lunwind not being found, and linking the shared library
will fail similarly.
Check if --unwindlib=none is supported, and add it in that case.
Using check_c_compiler_flag on its own doesn't work, because that only
adds the tested flag to the compilation command, and if -lunwind is
missing, the linking step would still fail - instead try adding it
to CMAKE_REQUIRED_FLAGS and restore the variable if it doesn't work.
This avoids having to pass --unwindlib=none while building libunwind.
Differential Revision: https://reviews.llvm.org/D112126
After recent changes to the Docker image, all hell broke loose and the
CI started failing. This patch marks a few tests as unsupported until
we can figure out what the issues are and fix them.
In the future, it would be ideal if the nodes could pick up the Dockerfile
present in the revision being tested, which would allow us to test changes
to the Dockerfile in the CI, like we do for all other code changes.
Differential Revision: https://reviews.llvm.org/D112737
There's a lot of duplicated calls to find various compiler-rt libraries
from build of runtime libraries like libunwind, libc++, libc++abi and
compiler-rt. The compiler-rt helper module already implemented caching
for results avoid repeated Clang invocations.
This change moves the compiler-rt implementation into a shared location
and reuses it from other runtimes to reduce duplication and speed up
the build.
Differential Revision: https://reviews.llvm.org/D88458
Instead of going through libc++'s run.py, we can simply run the executable
directly since we don't need to setup a working directory or control the
environment.
Differential Revision: https://reviews.llvm.org/D112649
Summary:
This commit switches libunwind from using the complicated logic in
libc++'s testing configuration to a from-scratch configuration.
I tried to make sure that all cases that were handled in the old
config were handled by this one too, so hopefully this shouldn't
break anyone. However, if you encounter issues with this change,
please let me know and feel free to revert if I don't reply quickly.
This change was engineered to be easily revertable.
This commit is a re-application of 5a8ad80b6f, which was reverted in
070a2ddcb6 because it broke the Bootstrapping build. This has now been
addressed by tweaking the from-scratch config.
Differential Revision: https://reviews.llvm.org/D112082
We recently introduced a from-scratch config to run the libunwind tests.
However, that config was always looking for libunwind in <install>/lib,
and never in <install>/<target>/lib, which is necessary for tests to
work when the per-target-runtime-dir configuration is enabled.
This commit fixes that. I believe this is what caused the CI failures we
saw after 5a8ad80b6f and caused it to be reverted.
Differential Revision: https://reviews.llvm.org/D112322
In 395271a, I simplified how we handled the target triple for the
runtimes. However, in doing so, we stopped considering the default
in CMAKE_CXX_COMPILER_TARGET, so we'd use the LLVM_DEFAULT_TARGET_TRIPLE
(which is the host triple) even if CMAKE_CXX_COMPILER_TARGET was specified.
This commit fixes that problem and also refactors the code so that it's
easy to see what the default value is.
The fact that nobody seems to have been broken by this makes me think
that perhaps nobody is using CMAKE_CXX_COMPILER_TARGET to specify the
triple -- but it should still work.
Differential Revision: https://reviews.llvm.org/D111672
This commit switches libunwind from using the complicated logic in
libc++'s testing configuration to a from-scratch configuration.
I tried to make sure that all cases that were handled in the old
config were handled by this one too, so hopefully this shouldn't
break anyone. However, if you encounter issues with this change,
please let me know and feel free to revert if I don't reply quickly.
This change was engineered to be easily revertable.
Differential Revision: https://reviews.llvm.org/D112082
Running tests for libunwind is a lot simpler than running tests for
libc++, so a simple Lit config file is sufficient. The benefit is that
we disentangle the libunwind test configuration from the libc++ and
libc++abi test configuration. The setup was too complicated, which led
to some bugs (notably we were running against the system libunwind on
Apple platforms).
Differential Revision: https://reviews.llvm.org/D111664
There's a lot of duplicated calls to find various compiler-rt libraries
from build of runtime libraries like libunwind, libc++, libc++abi and
compiler-rt. The compiler-rt helper module already implemented caching
for results avoid repeated Clang invocations.
This change moves the compiler-rt implementation into a shared location
and reuses it from other runtimes to reduce duplication and speed up
the build.
Differential Revision: https://reviews.llvm.org/D88458
Instead of always defining LIBCXXABI_NO_TIMER to run the tests, only
define LIBCXXABI_USE_TIMER when we want to enable the timer. This makes
the libc++abi testing configuration simpler.
As a fly-by fix, remove the unused LIBUNWIND_NO_TIMER macro from libunwind.
Differential Revision: https://reviews.llvm.org/D111667
Vendors take libc++ and ship it in various ways. Some vendors might
ship it differently from what upstream LLVM does, i.e. the install
location might be different, some ABI properties might differ, etc.
In the past few years, I've come across several instances where
having a place to test some of these properties would have been
incredibly useful. I also just got bitten by the lack of tests
of that kind, so I'm adding some now.
The tests added by this commit for Apple platforms have numerous
TODOs that capture discrepancies between the upstream LLVM CMake
and the slightly-modified build we perform internally to produce
Apple's system libc++. In the future, the goal would be to upstream
all those differences so that it's possible to build a faithful
Apple system libc++ with the upstream LLVM sources only.
But this isn't only useful for Apple - this lays out the path for
any vendor being able to add their own checks (either upstream or
downstream) to libc++.
This is a re-application of 9892d1644f, which was reverted in 138dc27186
because it broke the build. The issue was that we didn't apply the required
changes to libunwind and our CI didn't notice it because we were not
running the libunwind tests. This has been fixed now, and we're running
the libunwind tests in CI now too.
Differential Revision: https://reviews.llvm.org/D110736
We should arguably have always been doing that. The state of libunwind
is quite sad, so this commit adds several XFAILs to make the CI pass.
We need to investigate why so many tests are not passing in some
configurations, but I'll defer that to folks who actually work on
libunwind for lack of bandwidth.
Differential Revision: https://reviews.llvm.org/D110872
Fixes D110144.
registers.getFloatRegister is not const in ARM therefor can't be called here.
Reviewed By: mstorsjo, #libunwind
Differential Revision: https://reviews.llvm.org/D110731
During a backtrace the `.cfi_undefined` for a float register causes an assert in libunwind.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D110144
This way, we do not need to set LLVM_CMAKE_PATH to LLVM_CMAKE_DIR when (NOT LLVM_CONFIG_FOUND)
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D107717
-Wunused-but-set-variable triggers a warning even the block of code is effectively dead.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D107835
Control-flow Enforcement Technology (CET), published by Intel,
introduces shadow stack feature aiming to ensure a return from
a function is directed to where the function was called.
In a CET enabled system, each function call will push return
address into normal stack and shadow stack, when the function
returns, the address stored in shadow stack will be popped and
compared with the return address, program will fail if the 2
addresses don't match.
In exception handling, the control flow may skip some stack frames
and we must adjust shadow stack to avoid violating CET restriction.
In order to achieve this, we count the number of stack frames skipped
and adjust shadow stack by this number before jumping to landing pad.
Reviewed By: hjl.tools, compnerd, MaskRay
Differential Revision: https://reviews.llvm.org/D105968
Signed-off-by: gejin <ge.jin@intel.com>
The original libunwind project defines UNW_AARCH64_* instead of UNW_ARM64_*.
Rename the enum members to match. This allows some applications with simple
`unw_init_local` usage to migrate to llvm-project libunwind.
Note: the canonical names of `UNW_ARM_D{0..31}` are now `UNW_AARCH64_V{0..31}`,
to match the original libunwind.
UNW_ARM64_* are kept for now for compatibility. Some may be unneeded and can be
cleaned up in the future.
Reviewed By: #libunwind, compnerd
Differential Revision: https://reviews.llvm.org/D107996
In some binaries, built with clang/lld, libunwind crashes
with "unsupported x86_64 register" for regNum == 16:
Differential Revision: https://reviews.llvm.org/D107919
-Wunused-but-set-variable triggers a warning even the block of code is effectively dead.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D107835
_Unwind_ForcedUnwind is not mandated by the EHABI but for compatibilty
reasons adding so the interface to higher layers would be the same.
Dropping EHABI specific _Unwind_Stop_Fn definition since it is not defined by EHABI.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D89570
Moving Itanium and ArmEHABI specific implementations to dedicated files.
This is a NFC patch.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D106461
Currently, OR1K architecture put the program counter at offset 0x128 of
the current `or1k_thread_state_t`. However, the PC is restored after
updating the thread pointer in `r3`, which causes the PC to be fetched
incorrectly.
This patch swaps the order of restoration of `r9` and `r3`, such that
the PC is restored to `r9` using the current thread state.
Patch by Oi Chee Cheung!
Reviewed By: whitequark, compnerd
Differential Revision: https://reviews.llvm.org/D107042
Building the libraries with -fPIC ensures that we can link an executable
against the static libraries with -fPIE. Furthermore, there is apparently
basically no downside to building the libraries with position independent
code, since modern toolchains are sufficiently clever.
This commit enforces that we always build the runtime libraries with -fPIC.
This is another take on D104327, which instead makes the decision of whether
to build with -fPIC or not to the build script that drives the runtimes'
build.
Fixes http://llvm.org/PR43604.
Differential Revision: https://reviews.llvm.org/D104328
This is a NFC commit to normalize how we set target properties on the
various runtime targets. A follow-up patch is going to add new properties,
and I wanted that follow-up patch to be cleaner.
This commit modifies stepWithDwarf allowing for CFI directives to
specify the value of the stack pointer.
Previously, the SP would be unconditionally set to the CFA, because it
(wrongly) stated that the CFA is the stack pointer at the call site of a
function, but that is not always true.
One situation in which that is false, is for example if you have
switched stacks. In that case if you set the CFA to the SP before
switching the stack, the CFA would be far away from where the current
call frame is located.
The CFA always points to the current call frame, and that call frame
could have a CFI directive that specifies how to restore the stack
pointer. If not, it is OK to fallback and set the SP = CFA.
This change sets SP = CFA before restoring the registers during
unwinding, allowing the stack frame to be restored with a value
different than the CFA.
Reviewed By: #libunwind, phosek
Differential Revision: https://reviews.llvm.org/D106626
Instead of using TARGET_TRIPLE, which is always set to LLVM_DEFAULT_TARGET_TRIPLE,
use that variable directly to populate the various XXXX_TARGET_TRIPLE
variables in the runtimes.
This re-applies 77396bbc98 and 5099e01568, which were reverted in
850b57c5fb because they broke the build.
Differential Revision: https://reviews.llvm.org/D106009
When a target triple is specified in CMake via XXX_TARGET_TRIPLE, we tried
passing the --target=<...> flag to the compiler. However, not all compilers
support that flag (e.g. GCC, which is not a cross-compiler). As a result,
setting e.g. LIBCXX_TARGET_TRIPLE=<host-triple> would end up trying to
pass --target=<host-triple> to GCC, which breaks everything because the
flag isn't even supported.
This commit only adds `--target=<...>` & friends to the flags if it is
supported by the compiler.
One could argue that it's confusing to pass LIBCXX_TARGET_TRIPLE=<...>
and have it be ignored. That's correct, and one possibility would be
to assert that the requested triple is the same as the host triple when
we know the compiler is unable to cross-compile. However, note that this
is a pre-existing issue (setting the TARGET_TRIPLE variable never had an
influence on the flags passed to the compiler), and also fixing that is
starting to look like reimplementing a lot of CMake logic that is already
handled with CMAKE_CXX_COMPILER_TARGET.
Differential Revision: https://reviews.llvm.org/D106082
add_lit_testsuite() takes Lit parameters passed to it and adds them
to the parameters used globally when running all test suites. That
means that a target like `check-all`, which ends up calling Lit on
the whole monorepo, will see the test parameters for all the individual
project's test suites.
So, for example, it would see `--param std=c++03` (from libc++abi), and
`--param std=c++03` (from libc++), and `--param whatever` (from another
project being tested at the same time). While always unclean, that works
when the parameters all agree. However, if the parameters share the same
name but have different values, only one of those two values will be used
and it will be incredibly confusing to understand why one of the test
suites is being run with the incorrect parameter value.
For that reason, this commit moves away from using add_lit_testsuite()'s
PARAM functionality, and serializes the parameter values for the runtimes
in the generated config.py file instead, which is local to the specific
test suite.
Differential Revision: https://reviews.llvm.org/D105991
This commit reverts 5099e01568 and 77396bbc98, which broke the build
in various ways. I'm reverting until I can investigate, since that
change appears to be way more subtle than it seemed.
This is a second attempt at D101497, which landed as
9a9bc76c0e but had to be reverted in
8cf7ddbdd4.
This issue was that in the case that `COMPILER_RT_INSTALL_PATH` is
empty, expressions like "${COMPILER_RT_INSTALL_PATH}/bin" evaluated to
"/bin" not "bin" as intended and as was originally.
One solution is to make `COMPILER_RT_INSTALL_PATH` always non-empty,
defaulting it to `CMAKE_INSTALL_PREFIX`. D99636 adopted that approach.
But, I think it is more ergonomic to allow those project-specific paths
to be relative the global ones. Also, making install paths absolute by
default inhibits the proper behavior of functions like
`GNUInstallDirs_get_absolute_install_dir` which make relative install
paths absolute in a more complicated way.
Given all this, I will define a function like the one asked for in
https://gitlab.kitware.com/cmake/cmake/-/issues/19568 (and needed for a
similar use-case).
---
Original message:
Instead of using `COMPILER_RT_INSTALL_PATH` through the CMake for
complier-rt, just use it to define variables for the subdirs which
themselves are used.
This preserves compatibility, but later on we might consider getting rid
of `COMPILER_RT_INSTALL_PATH` and just changing the defaults for the
subdir variables directly.
---
There was a seaming bug where the (non-Apple) per-target libdir was
`${target}` not `lib/${target}`. I suspect that has to do with the docs
on `COMPILER_RT_INSTALL_PATH` saying was the library dir when that's no
longer true, so I just went ahead and fixed it, allowing me to define
fewer and more sensible variables.
That last part should be the only behavior changes; everything else
should be a pure refactoring.
---
I added some documentation of these variables too. In particular, I
wanted to highlight the gotcha where `-DSomeCachePath=...` without the
`:PATH` will lead CMake to make the path absolute. See [1] for
discussion of the problem, and [2] for the brief official documentation
they added as a result.
[1]: https://cmake.org/pipermail/cmake/2015-March/060204.html
[2]: https://cmake.org/cmake/help/latest/manual/cmake.1.html#options
In 38b2dec37e the problem was somewhat
misidentified and so `:STRING` was used, but `:PATH` is better as it
sets the correct type from the get-go.
---
D99484 is the main thrust of the `GnuInstallDirs` work. Once this lands,
it should be feasible to follow both of these up with a simple patch for
compiler-rt analogous to the one for libcxx.
Reviewed By: phosek, #libc_abi, #libunwind
Differential Revision: https://reviews.llvm.org/D105765
This is necessary for from-scratch configurations to support the 32-bit
mode of the test suite.
Differential Revision: https://reviews.llvm.org/D105435
"bad second level page" and "second level compressed unwind table"
can now be grepped for.
(Also remove one of the two spaces between "second" and "level"
in the second message.)
Now that Lit supports regular expressions inside XFAIL & friends, it is
much easier to write Lit annotations based on the triple.
Differential Revision: https://reviews.llvm.org/D104747
Before this patch, Lit parameters that were set as a result of CMake
options were not made available to from-scratch configs. This patch
serializes those parameters into the generated lit config file so that
they are available to all configs.
Differential Revision: https://reviews.llvm.org/D105047
Fix for the following exception.
AttributeError: 'TestingConfig' object has no attribute 'target_triple'
Related revision: https://reviews.llvm.org/D102012
'TestingConfig' object has no attribute 'target_triple'
Reviewed By: #libunwind, miyuki, danielkiss, mstorsjo
Differential Revision: https://reviews.llvm.org/D103140
This was regressed in adf1561d6c. Since gcc does not support
`__has_feature`, this adjusts the build to use the
`__SANITIZE_ADDRESS__` macro which GCC defines to identify if ASAN is
enabled (similar to `__has_feature`). This allows building libunwind
with gcc again.
Patch by Daniel Levin!
Reviewed By: compnerd
Differential Revision: https://reviews.llvm.org/D104176
This matches the fact that we build the experimental library by default.
Otherwise, by default we'd be building the library but not testing it,
which is inconsistent.
Differential Revision: https://reviews.llvm.org/D102109
If you're building libunwind instrumented with ASan, `_Unwind_RaiseException`
will poison the stack and then transfer control in a manner which isn't
understood by ASan, so the stack will remain poisoned. This can cause
false positives, e.g. if you call an uninstrumented function (so it
doesn't re-poison the stack) after catching an exception. Add a call to
`__asan_handle_no_return` inside `__unw_resume` to get ASan to unpoison
the stack and avoid this.
`__unw_resume` seems like the appropriate place to make this call, since
it's used for resumption by all unwind implementations except SJLJ. SJLJ
uses `__builtin_longjmp` to handle resumption, which is already
recognized as noreturn (and therefore ASan adds the `__asan_handle_no_return`
call itself), so it doesn't need any special handling.
PR32434 is somewhat similar (in particular needing a component built
without ASan to trigger the bug), and rG781ef03e1012, the fix for that
bug, adds an interceptor for `_Unwind_RaiseException`. This interceptor
won't always be triggered though, e.g. if you statically link the
unwinder into libc++abi in a way that prevents interposing the unwinder
functions (e.g. marking the symbols as hidden, using `--exclude-libs`,
or using `-Bsymbolic`). rG53335d6d86d5 makes `__cxa_throw` call
`__asan_handle_no_return` explicitly, to similarly avoid relying on
interception.
Reviewed By: #libunwind, compnerd
Differential Revision: https://reviews.llvm.org/D103002
This fixes a long standing issue where the triple is not always set
consistently in all configurations. This change also moves the
back-deployment Lit features to using the proper target triple
instead of using something ad-hoc.
This will be necessary for using from scratch Lit configuration files
in both normal testing and back-deployment testing.
Differential Revision: https://reviews.llvm.org/D102012
Summary:
This NFC patch replaces the representation of registers and the left shift operator in the PowerPC assembly code to allow it to be consumed by the GNU flavored assembler and the AIX assembler.
* Registers - change the representation of PowperPC registers from %rn, %fn, %vsn, and %vrn to the register number alone, e.g., n. The GNU flavored assembler and the AIX assembler are able to determine the register kind based on the context of the instruction in which the register is used.
* Left shift operator - use macro PPC_LEFT_SHIFT to represent the left shift operator. The left shift operator in the AIX assembly language is < instead of <<
Reviewed by: sfertile, MaskRay, compnerd
Differential Revision: https://reviews.llvm.org/D101179
The new layout more closely matches the layout used by other compilers.
This is only used when LLVM_ENABLE_PER_TARGET_RUNTIME_DIR is enabled.
Differential Revision: https://reviews.llvm.org/D100869
These variables were introduced during early work on the runtimes build
but were obsoleted by {LIBCXX,LIBCXXABI,LIBUNWIND}_INSTALL_LIBRARY_DIR.
Differential Revision: https://reviews.llvm.org/D99697
Prior to this patch, we would generate a fancy <__config> header by
concatenating <__config_site> and <__config>. This complexifies the
build system and also increases the difference between what's tested
and what's actually installed.
This patch removes that complexity and instead simply installs <__config_site>
alongside the libc++ headers. <__config_site> is then included by <__config>,
which is much simpler. Doing this also opens the door to having different
<__config_site> headers depending on the target, which was impossible before.
It does change the workflow for testing header-only changes to libc++.
Previously, we would run `lit` against the headers in libcxx/include.
After this patch, we run it against a fake installation root of the
headers (containing a proper <__config_site> header). This makes use
closer to testing what we actually install, which is good, however it
does mean that we have to update that root before testing header changes.
Thus, we now need to run `ninja check-cxx-deps` before running `lit` by
hand.
Differential Revision: https://reviews.llvm.org/D97572
immediate build failure when Cross Unwinding enabled.
Follow up patch will cleanup some Macros handling.
Differential Revision: https://reviews.llvm.org/D97762
Before this patch, we could only link against the back-deployment libc++abi
dylib. This patch allows linking against the just-built libc++abi, but
running against the back-deployment one -- just like we do for libc++.
Also, add XFAIL markup to flag expected errors.
Differential Revision: https://reviews.llvm.org/D91069
Rename the CMake option, LIBUNWIND_HERMETIC_STATIC_LIBRARY, to
LIBUNWIND_HIDE_SYMBOLS. Rename the C macro define,
_LIBUNWIND_DISABLE_VISIBILITY_ANNOTATIONS, to _LIBUNWIND_HIDE_SYMBOLS,
because now the macro adds a .hidden directive rather than merely
suppress visibility annotations.
For ELF, when LIBUNWIND_HIDE_SYMBOLS is enabled, mark unw_getcontext as
hidden. This symbol is the only one defined using src/assembly.h's
WEAK_ALIAS macro. Other unw_* weak aliases are defined in C++ and are
already hidden.
Mach-O doesn't support weak aliases, so remove .weak_reference and
weak_import. When LIBUNWIND_HIDE_SYMBOLS is enabled, output
.private_extern for the unw_* aliases.
In assembly.h, add missing SYMBOL_NAME macro invocations, which are
used to prefix symbol names with '_' on some targets.
Fixes PR46709.
Reviewed By: #libunwind, phosek, compnerd, steven_wu
Differential Revision: https://reviews.llvm.org/D93003
This change adds support for the dwarf PC register column in arm64, allowing
CFI directives to make use of it.
As of the last revision of the DWARF for ARM 64-bit architecture[0], the pc
register has been added as a valir register, with number 32.
This allows libunwinder to restore both pc and lr, which is useful
for stack switches and signal contexts.
[0]:
f52e1ad3f8/aadwarf64/aadwarf64.rst
Reviewed By: phosek, #libunwind
Differential Revision: https://reviews.llvm.org/D96901
Null return addresses can appear at the bottom of the stack (i.e. the
frame corresponding to the entry point). Authenticating these addresses
will set the error code in the address, which will lead to a segfault
in the sigreturn trampoline detection code. Fix this problem by not
authenticating null addresses.
Differential Revision: https://reviews.llvm.org/D96560
Let's use -nostdlib++ rather than -nodefaultlibs when building libc++/libc++abi/libunwind libraries. The default is -nostdlib++ if supported by a build compiler like it is the case with clang, otherwise -nodefaultlibs is used as before.
This change is needed to avoid additional changes at the link step and not to increase the maintenance costs. If clang with -nodefaultlibs is used all the libraries which are removed but required would have to be manually added in. This set of libraries are unique and will send out.
The propose change will allow to make the link step simple for other platforms as well.
Reviewed By: #libc, #libc_abi, ldionne
Differential Revision: https://reviews.llvm.org/D95875
An error has occurred when I build libunwind with -DLLVM_BUILD_DOCS=ON.
Reviewed By: #libunwind, compnerd
Differential Revision: https://reviews.llvm.org/D96107
cmake_minimum_required(VERSION) calls cmake_policy(VERSION),
which sets all policies up to VERSION to NEW.
LLVM started requiring CMake 3.13 last year, so we can remove
a bunch of code setting policies prior to 3.13 to NEW as it
no longer has any effect.
Reviewed By: phosek, #libunwind, #libc, #libc_abi, ldionne
Differential Revision: https://reviews.llvm.org/D94374
Modify libunwind to support SjLj exception handling routines for VE.
In order to do that, we need to implement not only SjLj exception
handling routines but also a Registers_ve class. This implementation
of Registers_ve is incomplete. We will work on it later when we need
backtrace in libunwind.
Reviewed By: #libunwind, compnerd
Differential Revision: https://reviews.llvm.org/D94591
An AArch64 sigreturn trampoline frame can't currently be described
in a DWARF .eh_frame section, because the AArch64 DWARF spec currently
doesn't define a constant for the PC register. (PC and LR may need to
be restored to different values.)
Instead, use the same technique as libgcc or github.com/libunwind and
detect the sigreturn frame by looking for the sigreturn instructions:
mov x8, #0x8b
svc #0x0
If a sigreturn frame is detected, libunwind restores all the GPRs by
assuming that sp points at an rt_sigframe Linux kernel struct. This
behavior is a fallback mode that is only used if there is no ordinary
unwind info for sigreturn.
If libunwind can't find unwind info for a PC, it assumes that the PC is
readable, and would crash if it isn't. This could happen if:
- The PC points at a function compiled without unwind info, and which
is part of an execute-only mapping (e.g. using -Wl,--execute-only).
- The PC is invalid and happens to point to unreadable or unmapped
memory.
In the tests, ignore a failed dladdr call so that the tests can run on
user-mode qemu for AArch64, which uses a stack-allocated trampoline
instead of a vDSO.
Reviewed By: danielkiss, compnerd, #libunwind
Differential Revision: https://reviews.llvm.org/D90898
* Remove misnamed `PPC64_HAS_VMX` in preference of directly checking `defined(__VSX__)`.
libunwind was using "VMX" to mean "VSX". "VMX" is just another name for Altivec, while "VSX" is the vector-scalar extensions first used in POWER7. Exposing a "PPC64_HAS_VMX" define was misleading and incorrect.
* Add `defined(__ALTIVEC__)` guards around vector register operations to fix non-altivec CPUS such as the e5500.
When compiling for certain Book-E processors such as the e5500, we want to skip vector save/restore, as the Altivec registers are illegal on non-Altivec implementations.
* Add `!defined(__NO_FPRS__)` guards around traditional floating-point save/restore.
When compiling for powerpcspe, we cannot access floating point registers, as there aren't any. (The SPE on e500v2 is a 64-bit extension of the GPRs, and it doesn't have the normal floating-point registers at all.)
This fixes building for powerpcspe, although no actual handling for SPE save/restore is written yet.
Reviewed By: MaskRay, #libunwind, compnerd
Differential Revision: https://reviews.llvm.org/D91906
When building the runtimes, it's very important not to add rpaths unless
the user explicitly asks for them (the standard way being CMAKE_INSTALL_RPATH),
or to change the install name dir unless the user requests it (via
CMAKE_INSTALL_NAME_DIR).
llvm_setup_rpath() would override the install_name_dir of the runtimes
even if CMAKE_INSTALL_NAME_DIR was specified to something, which is wrong
and in fact even "dangerous" for the runtimes.
This issue was discovered when trying to build libc++ and libc++abi as
system libraries for Apple, where we set the install name dir to /usr/lib
explicitly. llvm_setup_rpath() would cause libc++ to have the wrong install
name dir, and for basically everything on the system to fail to load.
This was discovered just now because we previously used something closer
to a standalone build, where llvm_setup_rpath() wouldn't exist, and hence
not be used.
This is a revert of the following commits:
libunwind: 3a667b9bd8
libc++abi: 4877063e19
libc++: 88434fe05f
Those added llvm_setup_rpath() for consistency, so it seems reasonable
to revert.
Differential Revision: https://reviews.llvm.org/D91099
ld64 uses them to create compact unwind from DWARF call frame information.
When the code was ported to libunwind, the variables were not deleted.
Reviewed By: #libunwind, compnerd
Differential Revision: https://reviews.llvm.org/D91039
Summary:
Before this patch, we could only link against the back-deployment libc++abi
dylib. This patch allows linking against the just-built libc++abi, but
running against the back-deployment one -- just like we do for libc++.
Also, add XFAIL markup to flag expected errors.
This patch just reorganises the code to make possible to use alloca
instead of malloc. This makes possible to use `.cfi_remember_state`/`.cfi_restore_state` on
platforms without heap allocation.
Also it will be safe to backtrace/unwind faults related to the allocator behind malloc.
`_LIBUNWIND_REMEMBER_HEAP_ALLOC ` option reenables the heap usage for `.cfi_remember_state`/`.cfi_restore_state`.
Define _LIBUNWIND_REMEMBER_STACK_ALLOC to force stack allocation.
Reviewed By: #libunwind, mstorsjo
Differential Revision: https://reviews.llvm.org/D85005
--export-dynamic is not always available on all targets.
-funwind-tables was a duplicate in the lit.site.cfg.in.
Reviewed By: ldionne
Differential Revision: https://reviews.llvm.org/D90202
This is a massive revert of the following commits (from most revent to oldest):
2b9b7b5775.
529ac3319728270234f169c2087283b5aa67446e5d796645d6
After checking-in the __config_site change, a lot of things started breaking
due to widespread reliance on various aspects of libc++'s build, notably the
fact that we can include the headers from the source tree, but also reliance
on various "internal" CMake variables used by the runtimes build and compiler-rt.
These were unintended consequences of the change, and after two days, we
still haven't restored all the bots to being green. Instead, now that I
understand what specific areas this will blow up in, I should be able to
chop up the patch into smaller ones that are easier to digest.
See https://reviews.llvm.org/D89041 for more details on this adventure.
Prior to this patch, we would generate a fancy <__config> header by
concatenating <__config_site> and <__config>. This complexifies the
build system and also increases the difference between what's tested
and what's actually installed.
This patch removes that complexity and instead simply installs <__config_site>
alongside the libc++ headers. <__config_site> is then included by <__config>,
which is much simpler. Doing this also opens the door to having different
<__config_site> headers depending on the target, which was impossible before.
It does change the workflow for testing header-only changes to libc++.
Previously, we would run `lit` against the headers in libcxx/include.
After this patch, we run it against a fake installation root of the
headers (containing a proper <__config_site> header). This makes use
closer to testing what we actually install, which is good, however it
does mean that we have to update that root before testing header changes.
Thus, we now need to run `ninja check-cxx-deps` before running `lit` by
hand.
This commit was originally applied in 1e46d1aa3 and reverted in eb60c487
because it broke the libc++abi and libunwind test suites. This has now
been fixed.
Differential Revision: https://reviews.llvm.org/D89041
Remove check for standalone and shared library mode in libcxxabi to
allow including tests in said mode. This check prevented running the
tests in standalone mode with static libraries, which is the case for
baremetal targets.
Fix check-unwind target trying to use a non-existent llvm-lit executable
in standalone mode. Copy the HandleOutOfTreeLLVM logic from libcxxabi to
libunwind in order to make the tests work in standalone mode.
Reviewed By: ldionne, #libc_abi, #libc
Differential Revision: https://reviews.llvm.org/D86540
There are several places in LLVM's CMake setup that try to remove the
`stdlib=...` flag from the CMake flags. All this code however only considered
the `-stdlib=` variant of the flag but not the alternative spelling with a
double dash. This causes that when one adds `--stdlib=...` to the user-provided
CMake flags that this gets transformed into just `-` which ends up causing the
build system to think it should read the source from stdin (which then lead to
very confusing build errors).
This just adds the alternative spelling before the`-stdlib=` variant in all
these places
Reviewed By: ldionne
Differential Revision: https://reviews.llvm.org/D87133
This unfortunately means that we don't execute C++ destructors when
unwinding past such frames for a different SEH unwind purpose (e.g.
as part of setjmp/longjmp), but that case isn't handled properly at
the moment (the original unwind intent is lost and we end up with an
unhandled exception). This patch makes sure the foreign unwind terminates
as intended.
After executing a handler, _Unwind_Resume doesn't have access to
the target frame parameter of the original foreign unwind. We also
currently blindly set ExceptionCode to STATUS_GCC_THROW - we could
set that correctly by storing the original code in _GCC_specific_handler,
but we don't have access to the original target frame value.
This also matches what libgcc's SEH unwinding code does in this case.
Differential Revision: https://reviews.llvm.org/D89231
This is needed when running the tests in Freestanding mode, where main()
isn't treated specially. In Freestanding, main() doesn't get mangled as
extern "C", so whatever runtime we're using fails to find the entry point.
One way to solve this problem is to define a symbol alias from __Z4mainiPPc
to _main, however this requires all definitions of main() to have the same
mangling. Hence this commit.
The .note.gnu.property must be in the assembly file to indicate the
support for BTI otherwise BTI will be disabled for the whole library.
__unw_getcontext and libunwind::Registers_arm64::jumpto() may be called
indirectly therefore they should start with a landing pad.
Reviewed By: tamas.petz, #libunwind, compnerd
Differential Revision: https://reviews.llvm.org/D77786
Currently, findUnwindSectionsByPhdr is slightly micro-optimized for the
case where the first callback has the target address, and is otherwise
very inefficient -- it decodes .eh_frame_hdr even when no PT_LOAD
matches the PC. (If the FrameHeaderCache is enabled, then the
micro-optimization only helps the first time unwind info is looked up.)
Instead, it makes more sense to optimize for the case where the
callback *doesn't* find the target address, so search for a PT_LOAD
segment first, and only look for the unwind info section if a matching
PT_LOAD is found.
This change helps on an Android benchmark with 100 shared objects,
where the DSO at the end of the dl_iterate_phdr list throws 10000
exceptions. Assuming the frame cache is disabled, this change cuts
about 30-40% off the benchmark's runtime.
Reviewed By: compnerd, saugustine, #libunwind
Differential Revision: https://reviews.llvm.org/D87881
dl_iterate_phdr is used to search for unwind info provided by either
PT_GNU_EH_FRAME or PT_ARM_EXIDX. Most of the code between the two is
the same, so combine them, and factor out what's different into
checkForUnwindInfoSegment.
Details:
- The FrameHeaderCache can now be enabled for ARM EHABI.
- findUnwindSectionsByPhdr now finds the last PT_ARM_EXIDX rather than
the first. There should only be one segment.
- The dso_base and text_segment_length fields of UnwindInfoSections
are now needed for dl_iterate_phdr when using EHABI, to hold the
low and high PC values for a cache entry.
Reviewed By: compnerd, danielkiss, #libunwind, saugustine
Differential Revision: https://reviews.llvm.org/D87880
Configure default value of `LLVM_ENABLE_WARNINGS` in `HandleLLVMOptions.cmake`.
`LLVM_ENABLE_WARNINGS` is documented as ON by default, but `HandleLLVMOptions` assumes the default has been set somewhere else. If it has not been explicitly set, then `HandleLLVMOptions` implicitly uses OFF as a default.
This removes the various `option()` declarations in favor of a single declaration in `HandleLLVMOptions`. This will prevent the unwanted use of `-w` that is mentioned in a couple of the comments.
Reviewed By: DavidTruby, #libunwind, JDevlieghere, compnerd
Differential Revision: https://reviews.llvm.org/D87243
Unwinding leaf function is useful in cases when the backtrace finds a
leaf function for example when it caused a signal.
This patch also add the support for the DW_CFA_undefined because it marks
the end of the frames.
Ryan Prichard provided code for the tests.
Reviewed By: #libunwind, mstorsjo
Differential Revision: https://reviews.llvm.org/D83573
Reland with limit the test to the x86_64-linux target.
Louis Dionne