[PATCH v3] Implement debugging of WOW64 processes in gdbserver

[Simon Marchi]

On 2020-04-30 10:13 a.m., Hannes Domani via Gdb-patches wrote:
> gdbserver/ChangeLog:
> 
> 2020-04-30  Hannes Domani  <ssbssa@yahoo.de>
> 
> 	* configure.srv <x86_64-*-mingw*, x86_64-*-cygwin*> (srv_tgtobj):
> 	Add arch/i386.o.
> 	* win32-arm-low.cc (arm_num_regs): New function.
> 	(struct win32_target_ops): Use arm_num_regs.
> 	* win32-i386-low.cc (win32_get_current_dr): Adapt for WOW64
> 	processes.
> 	(i386_get_thread_context): Likewise.
> 	(i386_prepare_to_resume): Likewise.
> 	(i386_thread_added): Likewise.
> 	(i386_single_step): Likewise.
> 	(i386_fetch_inferior_register): Likewise.
> 	(i386_store_inferior_register): Likewise.
> 	(i386_arch_setup): Likewise.
> 	(i386_win32_num_regs): New function.
> 	(struct win32_target_ops): Use i386_win32_num_regs.
> 	* win32-low.cc (win32_get_thread_context): Adapt for WOW64
> 	processes.
> 	(win32_require_context): Likewise.
> 	(child_add_thread): Likewise.
> 	(do_initial_child_stuff): Likewise.
> 	(continue_one_thread): Likewise.
> 	(win32_process_target::resume): Likewise.
> 	(load_psapi): Likewise.
> 	(win32_add_all_dlls): Likewise.
> 	(maybe_adjust_pc): Likewise.
> 	(win32_process_target::qxfer_siginfo): Likewise.
> 	(initialize_low): Likewise.
> 	* win32-low.h (struct win32_target_ops): Change num_regs to
> 	callback function.
> ---
> v2:
> - Stop with error() if any of the WOW64 functions is not available when
>   debugging WOW64 processes.
> 
> v3:
> - Some more comments.
> - Error if IsWow64Process fails.
> - Removed win32_Wow64SuspendThread since it's not (yet) used.

Even if calling SuspendThread to suspend a WOW64 thread from a 64-bits GDB works,
we might still want to use Wow64SuspendThread, since it's the "right" thing to do.

Either way, this is OK.

Simon