Add FreeBSD/aarch64 support

[myfreeweb]

I'm actually quite confused about how aarch64 contexts are implemented…

• there's unw_tdep_context_t / unw_sigcontext, a private copy of Linux structs
  • filled by the inline assembly in the unw_tdep_getcontext macro??
  • but there was a reference to fpsimd_context from Linux system headers??
  • the assembly does not seem to save the float/simd registers though??

So I added an internal Linux-compatible fpsimd struct and that compiles…

I'm not sure how to properly test, make check tries to link the library twice for some reason:

/usr/bin/ld: error: duplicate symbol: dwarf_search_unwind_table_int
>>> defined at Gfind_proc_info-lsb.c:809 (dwarf/Gfind_proc_info-lsb.c:809)
>>>            Gfind_proc_info-lsb.o:(_Uaarch64_dwarf_search_unwind_table) in archive ../src/.libs/libunwind-aarch64.a
>>> defined at Gfind_proc_info-lsb.c:809 (dwarf/Gfind_proc_info-lsb.c:809)
>>>            Lfind_proc_info-lsb.o:(_ULaarch64_dwarf_search_unwind_table) in archive /mnt/greg/src/github.com/libunwind/libunwind/src/.libs/libunwind.a

Tried to run something manually:

• run-coredump-unwind (and -mdi) expect GNU binaries: mktemp: illegal option -- -
• test-ptrace-misc returns sum = 0
• test-strerror and test-proc-info exit 0 without printing anything
• forker segfaults in strtol_l
• the example from issue #68 prints something reasonable (ip = 20394, sp = ffffffffdaf0) and does not segfault! :)

[djwatson]

This patch seems to implement _UPT_access_fpreg for aarch64, is that correct?

It looks fine to me for that, but your PR title and description seem to be completely unrelated to what the patch is doing.

[djwatson]

This patch seems to implement _UPT_access_fpreg for aarch64, is that correct?

It looks fine to me for that, but your PR title and description seem to be completely unrelated to what the patch is doing.

[myfreeweb]

@djwatson that's one part of it. (yeah I didn't even notice that wasn't OS-specific) there's also aarch64 support in _UCD_access_reg_freebsd.c, and unw_fpsimd_context_t instead of using that struct directly from Linux headers to make it work on FreeBSD

[myfreeweb]

@djwatson that's one part of it. (yeah I didn't even notice that wasn't OS-specific) there's also aarch64 support in _UCD_access_reg_freebsd.c, and unw_fpsimd_context_t instead of using that struct directly from Linux headers to make it work on FreeBSD

[djwatson]

Gotchya. Updating the commit message and merging, thanks.

[djwatson]

Gotchya. Updating the commit message and merging, thanks.