This makes it possible to unwind hardware exception stack frames,
which necessarily save every register and so need an extra column
for storing the return address. CFI for the exception handler could
then look as follows:
.globl exception_vector
exception_vector:
.cfi_startproc
.cfi_signal_frame
.cfi_return_column 32
l.addi r1, r1, -0x100
.cfi_def_cfa_offset 0x100
l.sw 0x00(r1), r2
.cfi_offset 2, 0x00-0x100
l.sw 0x04(r1), r3
.cfi_offset 3, 0x04-0x100
l.sw 0x08(r1), r4
.cfi_offset 4, 0x08-0x100
l.mfspr r3, r0, SPR_EPCR_BASE
l.sw 0x78(r1), r3
.cfi_offset 32, 0x78-0x100
l.jal exception_handler
l.nop
l.lwz r2, 0x00(r1)
l.lwz r3, 0x04(r1)
l.lwz r4, 0x08(r1)
l.jr r9
l.nop
.cfi_endproc
This register could, of course, also be accessed by the trace
callback or personality function, if so desired.
llvm-svn: 332513
Before this commit, R9, the link register, was used as PC register.
However, a stack frame may have R9 not set to PC on entry, either
because it uses a custom calling convention, or, more likely,
because this is a signal or exception stack frame. Using R9 as
PC register made it impossible to unwind such frames.
All other architectures similarly use a dedicated PC register.
llvm-svn: 332512
Summary:
For MIPS ABIs with 64-bit floating point registers including newabi
and O32 with 64-bit floating point registers, just save and restore the
32 floating-point registers as doubles.
For O32 MIPS with 32-bit floating-point registers, save and restore the
individual floating-point registers as "plain" registers. These registers
are encoded as floats rather than doubles, but the DWARF unwinder
assumes that floating-point registers are stored as doubles when reading
them from memory (via AddressSpace::getDouble()). Treating the
registers as "normal" registers instead causes the DWARF unwinder to
fetch them from memory as a 32-bit register. This does mean that for
O32 with 32-bit floating-point registers unw_get_fpreg() and
unw_set_fpreg() do not work. One would have to use unw_get_reg()
and unw_set_reg() instead. However, DWARF unwinding works
correctly as the DWARF CFI emits records for individual 32-bit
floating-point registers even when they are treated as doubles stored
in paired registers. If the lack of unw_get/set_fpreg() becomes a pressing
need in the future for O32 MIPS we could add in special handling to
make it work.
Reviewers: sdardis, compnerd
Reviewed By: sdardis
Differential Revision: https://reviews.llvm.org/D41968
llvm-svn: 332414
CMAKE_CXX_FLAGS and CMAKE_C_FLAGS are added twice to the command line.
This causes the command line options to be doubled which works until
it doesn't as not all options can be specified twice.
For example,
clang-cl foo.c /GS- /GS- -mllvm -small-loop-cost=1 -mllvm -small-loop-cost=1
clang (LLVM option parsing): for the -small-loop-cost option: may only occur zero or one times!
llvm-svn: 329340
Summary:
N32 uses the same register context as N64. However, N32 requires one
change to properly fetch addresses from registers stored in memory.
Since N32 is an ILP32 platform, getP() only fetches the first 32-bits
of a stored register. For a big-endian platform this fetches the
upper 32-bits which will be zero. To fix this, add a new
getRegister() method to AddressSpace which is responsible for
extracting the address stored in a register in memory. This matches
getP() for all current ABIs except for N32 where it reads the 64-bit
register and returns the low 32-bits as an address. The
DwarfInstructions::getSavedRegister() method uses
AddressSpace::getRegister() instead of AddressSpace::getP().
Reviewers: sdardis, compnerd
Reviewed By: sdardis
Differential Revision: https://reviews.llvm.org/D39074
llvm-svn: 326250
Summary:
This is done via new LIBUNWIND_TEST_COMPILER_FLAGS and
LIBUNWIND_TEST_LINKER_FLAGS variables.
Reviewed By: sdardis
Differential Revision: https://reviews.llvm.org/D43585
llvm-svn: 326223
Otherwise, a shared library build with SJLJ APIs enabled would
end up with duplicate symbols.
This didn't occur for the apple && arm case due to specifically
checking for that in the surrounding ifdef.
Differential Revision: https://reviews.llvm.org/D42555
llvm-svn: 323499
Clang and llvm already use llvm_setup_rpath(), so this change will
help standarize rpath usage across all projects.
Differential Revision: https://reviews.llvm.org/D42461
llvm-svn: 323496
When CMAKE_SYSROOT or CMAKE_FIND_ROOT_PATH is set, cmake
recommends setting CMAKE_FIND_ROOT_PATH_MODE_INCLUDE=ONLY
globally which means find_path() always prepends CMAKE_SYSROOT or
CMAKE_FIND_ROOT_PATH to all paths used in the search.
However, this find_path() invocation is looking for a path in the
libcxx project on the host system, not the target system,
which can be done by passing NO_CMAKE_FIND_ROOT_PATH.
Differential Revision: https://reviews.llvm.org/D41621
llvm-svn: 323141
The Registers_ppc64 class needed a couple of changes, both to accommodate the
new registers as well as to handle the overlaps of VS register set
without wasting space.
The save/restore code of V and VS registers was added.
As VS registers depend on the VMX extension, they are processed only if
VMX support is detected (_ARCH_PWR8 for now).
Patch by Leandro Lupori!
Differential Revision: https://reviews.llvm.org/D41906
llvm-svn: 322596
This is in preparation for adding support for N32 unwinding which reuses
the newabi register class.
Reviewed By: compnerd
Differential Revision: https://reviews.llvm.org/D41842
llvm-svn: 322093
Initial working version of libunwind for PowerPC 64. Tested on
little-endian ppc64 host only.
Based on the existing PowerPC 32 code.
It supports:
- context save/restore (unw_getcontext, unw_init_local, unw_resume)
- read/write from/to saved registers
- backtrace (unw_step)
Patch by Leandro Lupori!
Differential Revision: https://reviews.llvm.org/D41386
Now builds with LIBUNWIND_ENABLE_CROSS_UNWINDING=ON should
work.
llvm-svn: 321680
For builds that only target one architecture, this was required to
be an exact match, while it previously required the allocation to be
strictly larger than the largest concrete one. Requiring it to be
larger than on equal should be enough.
This makes it more straightforward to update _LIBUNWIND_CONTEXT_SIZE
and _LIBUNWIND_CURSOR_SIZE.
llvm-svn: 321679
Initial working version of libunwind for PowerPC 64. Tested on
little-endian ppc64 host only.
Based on the existing PowerPC 32 code.
It supports:
- context save/restore (unw_getcontext, unw_init_local, unw_resume)
- read/write from/to saved registers
- backtrace (unw_step)
Patch by Leandro Lupori!
Differential Revision: https://reviews.llvm.org/D41386
llvm-svn: 321667
Instead, cast them to `void *` which has a portable format string syntax
of `%p`.
This fixes a -Wformat error when building libunwind.
llvm-svn: 321469
Right now, ARM EHABI unwind on bare metal expects to find the symbols
__exidx_start and __exidx_end defined, and uses those to locate
the EH tables. However, DWARF unwind on bare metal expects to find
dl_iterate_phdr, which, although possible to provide, is inconvenient
and mildly absurd.
This commit provides feature parity with ARM EHABI unwind by looking
for symbols __eh_frame_start, __eh_frame_end, __eh_frame_hdr_start
and __eh_frame_hdr_end, denoting the start and end of the sections
with corresponding names. As far as I know, there is no de jure or
de facto ABI providing any such names, so I chose the obvious ones.
The .eh_frame_hdr support is optional for maximum flexibility and
possible space savings (e.g. if libunwind is only used to provide
backtraces when a device crashes, providing the .eh_frame_hdr, which
is an index for rapid access to EH tables, would be a waste.)
The support for .eh_frame_hdr/DWARF index in the first place is
conditional on defined(_LIBUNWIND_SUPPORT_DWARF_INDEX), although
right now config.h will always define this macro.
The support for DWARF unwind on bare metal has been validated within
the ARTIQ environment[1].
[1]: https://m-labs.hk/artiq/
llvm-svn: 321445
Use the `_LIBUNWIND_LOG` and `_LIBUNWIND_LOG0` macros instead of
the explicit `fprintf` call.
This was previously done in r292721 as a cleanup and then reverted
in r293257 because the implementation in r292721 relied on a GNU
extension. This implementation avoids the use of an extension
by using a second macro instead, and allows to avoid the dependency
on fprintf if _LIBUNWIND_BARE_METAL is defined.
llvm-svn: 321441
This supports the soft-float ABI only and has been tested with both clang
and gcc on FreeBSD.
Reviewed By: sdardis, compnerd
Differential Revision: https://reviews.llvm.org/D38110
llvm-svn: 320528
This supports using a newer libunwind with an older installation of LLVM
(whose cmake modules wouldn't have add_llvm_install_targets).
llvm-svn: 320163
This follows the setup used by other runtimes and is expected by
the lit configuration.
Differential Revision: https://reviews.llvm.org/D40820
llvm-svn: 319830
This gains us the install-unwind-stripped target, to perform stripping
during installation.
Differential Revision: https://reviews.llvm.org/D40685
llvm-svn: 319498
This is useful in cases where we only build static library and
libunwind.a is combined with libc++abi.a into a single archive in which
case we don't want to have libunwind.a installed separately. The same
option is already provided by libcxx CMake build.
This change also adds the install-unwind target for consistency with the
libcxxabi and libcxx CMake build.
Differential Revision: https://reviews.llvm.org/D40195
llvm-svn: 318569
If the linker chose to store the full section name instead of truncating
it, this field doesn't contain a truncated name, but an offset into
the string table of the binary. The string table isn't loaded/mapped
into memory during runtime though, so it's not possible to read the
full section name, unless we try to locate the DLL/EXE on disk that
the HMODULE corresponds to and load that manually.
Due to this, lld now always prefers writing a truncated section name
for sections that will be mapped at runtime, even when debug info is
enabled.
Differential Revision: https://reviews.llvm.org/D39918
llvm-svn: 318446
This didn't require any further changes to libunwind as long as win64
in general is handled correctly.
Differential Revision: https://reviews.llvm.org/D39632
llvm-svn: 318383
The previous definition of _LIBUNWIND_HIGHEST_DWARF_REGISTER seems
to be a copy of the ARM64 value (introduced in SVN r276128); since
the code actually hasn't compiled properly for arm in dwarf mode
before, this hasn't actually been used. Set it to the correct value
based on the UNW_ARM_* enum values.
The iwmmx control variables have to be made mutable, since they are
touched from within getRegister (which previously wasn't const), and
getRegister is used on a const Registers object in DwarfInstructions.hpp.
Differential Revision: https://reviews.llvm.org/D39251
llvm-svn: 317192
This matches the original libunwind API. This also unifies the
type between ARM EHABI and the other configurations, and allows
getting rid of a number of casts in log messages.
The cursor size updates for ppc and or1k are untested, but
unw_proc_info_t shrinks by 4 uint64_t units on i386 at least.
Differential Revision: https://reviews.llvm.org/D39365
llvm-svn: 316942
This restores the previous behaviour of the Registers_* classes
after SVN r316745.
Differential Revision: https://reviews.llvm.org/D39382
llvm-svn: 316843
Clang doesn't currently support building for windows/x86_64 with
dwarf by setting command line parameters, but if manually modified
to use dwarf, we can make libunwind work in this configuration
as well.
Also include i386 in the docs when adding this as a supported
configuration; libunwind already works for i386 windows, but
can fail due to an issue unrelated to windows itself.
Differential Revision: https://reviews.llvm.org/D38819
llvm-svn: 316747
This avoids having to keep the same information duplicated in multiple
places.
Adjust _LIBUNWIND_HIGHEST_DWARF_REGISTER to actually have the value
of the highest used register and only use the value
_LIBUNWIND_HIGHEST_DWARF_REGISTER + 1 (kMaxRegisterNumber + 1) for
allocating the savedRegisters array.
Differential Revision: https://reviews.llvm.org/D39281
llvm-svn: 316745
For many targets setting -fno-exceptions will prevent unwinding tables from
being generated for the test programs. As libunwind depends on the tables to
unwind the stack several tests will fail.
This change always adds -funwind-tables so that even when -fno-exceptions
is set unwind tables are generated.
fixes PR33858
Differential Revision: https://reviews.llvm.org/D37484
llvm-svn: 316657
This was missed in SVN r274744 when the WMMX part was made optional;
when made optional, some struct fields were reordered, which caused
the total struct size to grow due to padding/alignment.
llvm-svn: 316559
Most other cases that touch savedRegisters[reg] have got this check,
but these three seemed to lack it.
Differential Revision: https://reviews.llvm.org/D39206
llvm-svn: 316415
This requires _WIN32_WINNT >= 0x0600.
If someone wants to spend effort on supporting earlier versions,
one can easily add another fallback implementation based on
critical sections, or try to load SRW lock functions dynamically.
This makes sure that the FDE cache is thread safe on windows.
Differential Revision: https://reviews.llvm.org/D38704
llvm-svn: 316364
This avoids a hack for making it a no-op for windows.
Also explicitly check for _WIN32 instead of assuming it.
Differential Revision: https://reviews.llvm.org/D39156
llvm-svn: 316300
If there is no binary search table computed, the FDECount encoding is
DW_EH_PE_omit. Do not attempt to read the FDECount in such a situation
as we will read an incorrect value. binutils only writes out the
FDECount if the encoding is not DW_EH_PE_omit.
llvm-svn: 316224
whitequark