Re: PATCH: Check bfd_mach_x64_32 to set tdesc for x32 binary

["H.J. Lu" <hjl.tools@gmail.com>]

On Fri, May 11, 2012 at 4:13 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Fri, May 11, 2012 at 1:20 PM, Mark Kettenis <mark.kettenis@xs4all.nl> wrote:
>>> Hi,
>>>
>>> This patch checks bfd_mach_x64_32 to set tdesc for x32 binary.  Tested
>>> on Linux/x86-64.  OK to install?
>>>
>>> Thanks.
>>>
>>>
>>> H.J.
>>> ---
>>>       * amd64-linux-tdep.c: Include features/i386/x32-linux.c
>>>       and features/i386/x32-avx-linux.c.
>>>       (amd64_linux_init_abi): Check bfd_mach_x64_32 for x32 process.
>>>       (_initialize_amd64_linux_tdep): Register bfd_mach_x64_32.  Call
>>>       initialize_tdesc_x32_linux and initialize_tdesc_x32_avx_linux.
>>>
>>>       * amd64-linux-tdep.h (tdesc_x32_linux): New.
>>>       (tdesc_x32_avx_linux): Likewise.
>>>
>>> diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
>>> index acc7303..601ce20 100644
>>> --- a/gdb/amd64-linux-tdep.c
>>> +++ b/gdb/amd64-linux-tdep.c
>>> @@ -1545,8 +1578,12 @@ _initialize_amd64_linux_tdep (void)
>>>  {
>>>    gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
>>>                         GDB_OSABI_LINUX, amd64_linux_init_abi);
>>> +  gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x64_32,
>>> +                       GDB_OSABI_LINUX, amd64_linux_init_abi);
>>
>> Instead of doing this, you should introduce an
>> amd64_x32_linux_init_abi() function, make that call amd64_linix_init_abi() and ovverride the bits that are different for X32.
>
> I don't think I should override tdep->tdesc.  Here is a different approach.
> I updated amd64_linux_init_abi to take amd64_linux_tdesc and fetch_func.
> I also added amd64_lp64_linux_init_abi and amd64_ilp32_linux_init_abi
> to pass the right ones to amd64_linux_init_abi.  Tested on Linux/x86-64.
> OK to install?
>
> Thanks.
>
> --
> H.J.
> --
>        * amd64-linux-tdep.c (amd64_linux_init_abi): Add 2 arguments,
>        amd64_linux_tdesc and fetch_func.  Replace tdesc_amd64_linux
>        with amd64_linux_tdesc and svr4_lp64_fetch_link_map_offsets
>        with fetch_func.
>        (amd64_lp64_linux_init_abi): New function.
>        (amd64_ilp32_linux_init_abi): Likewise.
>        (_initialize_amd64_linux_tdep): Replace amd64_linux_init_abi
>        with amd64_lp64_linux_init_abi.  Register bfd_mach_x64_32 with
>        amd64_ilp32_linux_init_abi.  Call initialize_tdesc_x32_linux
>        and initialize_tdesc_x32_avx_linux.
>

An updated patch to remove the change which are already in
trunk.  OK to install?

Thanks.

-- 
H.J.
---
	* amd64-linux-tdep.c (amd64_linux_init_abi): Add 2 arguments,
	amd64_linux_tdesc and fetch_func.  Replace tdesc_amd64_linux
	with amd64_linux_tdesc and svr4_lp64_fetch_link_map_offsets
	with fetch_func.
	(amd64_lp64_linux_init_abi): New function.
	(amd64_ilp32_linux_init_abi): Likewise.
	(_initialize_amd64_linux_tdep): Replace amd64_linux_init_abi
	with amd64_lp64_linux_init_abi.  Register bfd_mach_x64_32 with
	amd64_ilp32_linux_init_abi.

diff --git a/gdb/amd64-linux-tdep.c b/gdb/amd64-linux-tdep.c
index cfe6e4b..e68d70f 100644
--- a/gdb/amd64-linux-tdep.c
+++ b/gdb/amd64-linux-tdep.c
@@ -1288,7 +1288,9 @@ amd64_linux_core_read_description (struct
gdbarch *gdbarch,
 }

 static void
-amd64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+amd64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch,
+		      const struct target_desc *amd64_linux_tdesc,
+		      struct link_map_offsets *(*fetch_func) (void))
 {
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   const struct target_desc *tdesc = info.target_desc;
@@ -1310,7 +1312,7 @@ amd64_linux_init_abi (struct gdbarch_info info,
struct gdbarch *gdbarch)
   set_gdbarch_num_regs (gdbarch, AMD64_LINUX_NUM_REGS);

   if (! tdesc_has_registers (tdesc))
-    tdesc = tdesc_amd64_linux;
+    tdesc = amd64_linux_tdesc;
   tdep->tdesc = tdesc;

   feature = tdesc_find_feature (tdesc, "org.gnu.gdb.i386.linux");
@@ -1331,8 +1333,7 @@ amd64_linux_init_abi (struct gdbarch_info info,
struct gdbarch *gdbarch)
   tdep->xsave_xcr0_offset = I386_LINUX_XSAVE_XCR0_OFFSET;

   /* GNU/Linux uses SVR4-style shared libraries.  */
-  set_solib_svr4_fetch_link_map_offsets
-    (gdbarch, svr4_lp64_fetch_link_map_offsets);
+  set_solib_svr4_fetch_link_map_offsets (gdbarch, fetch_func);

   /* Add the %orig_rax register used for syscall restarting.  */
   set_gdbarch_write_pc (gdbarch, amd64_linux_write_pc);
@@ -1543,6 +1544,22 @@ amd64_linux_init_abi (struct gdbarch_info info,
struct gdbarch *gdbarch)

   tdep->i386_syscall_record = amd64_linux_syscall_record;
 }
+
+static void
+amd64_lp64_linux_init_abi (struct gdbarch_info info,
+			   struct gdbarch *gdbarch)
+{
+  amd64_linux_init_abi (info, gdbarch, tdesc_amd64_linux,
+			svr4_lp64_fetch_link_map_offsets);
+}
+
+static void
+amd64_ilp32_linux_init_abi (struct gdbarch_info info,
+			   struct gdbarch *gdbarch)
+{
+  amd64_linux_init_abi (info, gdbarch, tdesc_x32_linux,
+			svr4_ilp32_fetch_link_map_offsets);
+}



 /* Provide a prototype to silence -Wmissing-prototypes.  */
@@ -1552,7 +1589,9 @@ void
 _initialize_amd64_linux_tdep (void)
 {
   gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
-			  GDB_OSABI_LINUX, amd64_linux_init_abi);
+			  GDB_OSABI_LINUX, amd64_lp64_linux_init_abi);
+  gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x64_32,
+			  GDB_OSABI_LINUX, amd64_ilp32_linux_init_abi);

   /* Initialize the Linux target description.  */
   initialize_tdesc_amd64_linux ();