llvm-capstone/libunwind/test
Ryan Prichard c82deed676 [libunwind] Unwind through aarch64/Linux sigreturn frame
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
2021-01-13 16:38:36 -08:00
..
libunwind Revert "Allow running back-deployment testing against libc++abi" 2020-11-06 17:26:42 -05:00
alignment.compile.pass.cpp
CMakeLists.txt
frameheadercache_test.pass.cpp
libunwind_01.pass.cpp
libunwind_02.pass.cpp
lit.cfg.py
lit.site.cfg.in Revert "Allow running back-deployment testing against libc++abi" 2020-11-06 17:26:42 -05:00
remember_state_leak.pass.sh.s
signal_frame.pass.cpp
signal_unwind.pass.cpp [libunwind] Unwind through aarch64/Linux sigreturn frame 2021-01-13 16:38:36 -08:00
unw_getcontext.pass.cpp
unwind_leaffunction.pass.cpp [libunwind] Unwind through aarch64/Linux sigreturn frame 2021-01-13 16:38:36 -08:00