Re: [Libunwind-devel] [PATCHv3 1/4] Add core dump unwinding support to libunwind

[Denys Vlasenko]

On 03/24/2012 11:31 PM, Arun Sharma wrote:
> On Fri, Mar 16, 2012 at 5:53 AM, Denys Vlasenko<address@hidden>  wrote:
>
> > I want this code to end up in libunwind.so instead,
> > so we can use it equally from both libs.
> >
> > Our predicament seems to be that we have no good
> > place to put its source in the source tree, right?
> >
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 arm
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 hppa
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 ia64
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 mi
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 mips
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 ppc
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 ppc32
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 ppc64
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 x86
> > drwxr-xr-x. 2 root root  4096 Feb 13 18:43 x86_64
> >
> > The above dirs are arch specific - not suitable.
>
> The code is also ia64 specific. I don't have any objections to putting
> it under ia64.

It isn't.

Please take a look at src/ptrace/_UPT_find_proc_info.c
(before patching. Current git, for example).

It has the following structure:


#if UNW_TARGET_IA64

static unw_word_t
find_gp (struct UPT_info *ui, Elf64_Phdr *pdyn, Elf64_Addr load_base) ...
HIDDEN int
_UPTi_find_unwind_table (struct UPT_info *ui, unw_addr_space_t as,
                         char *path, unw_word_t segbase, unw_word_t mapoff,
                         unw_word_t ip) ...

#elif UNW_TARGET_X86 || UNW_TARGET_X86_64 || UNW_TARGET_HPPA \
|| UNW_TARGET_PPC32 || UNW_TARGET_PPC64 || UNW_TARGET_ARM

int
dwarf_read_encoded_pointer (unw_addr_space_t as, unw_accessors_t *a,
                            unw_word_t *addr, unsigned char encoding,
                            const unw_proc_info_t *pi,
                            unw_word_t *valp, void *arg) ...
HIDDEN int
_UPTi_find_unwind_table (struct UPT_info *ui, unw_addr_space_t as,
                         char *path, unw_word_t segbase, unw_word_t mapoff,
                         unw_word_t ip) ...

#endif /* UNW_TARGET_X86 || UNW_TARGET_X86_64 || UNW_TARGET_HPPA*/

static int
get_unwind_info (struct UPT_info *ui, unw_addr_space_t as, unw_word_t ip) ...
int
_UPT_find_proc_info (unw_addr_space_t as, unw_word_t ip, unw_proc_info_t *pi,
                     int need_unwind_info, void *arg) ...

Thus, find_unwind_table exists for all architectures, not only for IA64.
It just has two different implementations: one for IA64, and another for e


> Re: common
>
> There is also a dir called "mi" (machine independent). But this is
> arch specific code, so we shouldn't move it there.

Actually it might be a good place...

Please find attached patch which moves find_proc_info() to mi/*.

--
vda

z1.patch
Description: Text Data