[PATCH v2 07/11] s390: Hook s390 into OSABI mechanism

Philipp Rudo
2017-12-05T12:29:18Z

Well do what the title says and distinguish between 31- and 64-bit systems.

There is one pitfall to take care of. Appending the dwarf2 unwinder must
be moved _before_ the OSABI is initialized. Otherwise a default unwinder
will take control before the dwarf unwinder even gets a chance.

gdb/ChangeLog:

* s390-linux-tdep.c (osabi.h): New include
(s390_linux_init_osabi_31, s390_linux_init_osabi_64)
(s390_linux_init_osabi_any): New functions.
(s390_gdbarch_init): Adjust.
---
gdb/s390-linux-tdep.c | 155 +++++++++++++++++++++++++++++---------------------
1 file changed, 91 insertions(+), 64 deletions(-)

diff --git a/gdb/s390-linux-tdep.c b/gdb/s390-linux-tdep.c
index f6a39868be..f8559eec49 100644
--- a/gdb/s390-linux-tdep.c
+++ b/gdb/s390-linux-tdep.c
@@ -30,6 +30,7 @@
#include "gdbcore.h"
#include "gdbcmd.h"
#include "objfiles.h"
+#include "osabi.h"
#include "regcache.h"
#include "trad-frame.h"
#include "frame-base.h"
@@ -8024,32 +8025,12 @@ s390_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
struct tdesc_arch_data *tdesc_data = tdesc_data_alloc ();
info.tdesc_data = tdesc_data;

- /* Default ABI and register size. */
- switch (info.bfd_arch_info->mach)
- {
- case bfd_mach_s390_31:
- tdep->abi = ABI_LINUX_S390;
- break;
-
- case bfd_mach_s390_64:
- tdep->abi = ABI_LINUX_ZSERIES;
- break;
-
- default:
- xfree (tdep);
- gdbarch_free (gdbarch);
- return NULL;
- }
+ /* The DWARF unwinders must be appended before the ABI is initialized.
+ Otherwise it is possible that a ABI default unwinder gets called before
+ the DWARF unwinder even gets the chance. */
+ dwarf2_append_unwinders (gdbarch);

- /* Use default target description if none provided by the target. */
- if (!tdesc_has_registers (tdesc))
- {
- if (tdep->abi == ABI_LINUX_S390)
- tdesc = tdesc_s390_linux32;
- else
- tdesc = tdesc_s390x_linux64;
- }
- tdep->tdesc = tdesc;
+ gdbarch_init_osabi (info, gdbarch);

/* Check any target description for validity. */
gdb_assert (tdesc_has_registers (tdep->tdesc));
@@ -8100,12 +8081,7 @@ s390_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
set_gdbarch_stab_reg_to_regnum (gdbarch, s390_dwarf_reg_to_regnum);
set_gdbarch_dwarf2_reg_to_regnum (gdbarch, s390_dwarf_reg_to_regnum);
set_gdbarch_value_from_register (gdbarch, s390_value_from_register);
- set_gdbarch_core_read_description (gdbarch, s390_core_read_description);
- set_gdbarch_iterate_over_regset_sections (gdbarch,
- s390_iterate_over_regset_sections);
set_gdbarch_cannot_store_register (gdbarch, s390_cannot_store_register);
- set_gdbarch_write_pc (gdbarch, s390_write_pc);
- set_gdbarch_guess_tracepoint_registers (gdbarch, s390_guess_tracepoint_registers);
set_gdbarch_pseudo_register_read (gdbarch, s390_pseudo_register_read);
set_gdbarch_pseudo_register_write (gdbarch, s390_pseudo_register_write);
set_tdesc_pseudo_register_name (gdbarch, s390_pseudo_register_name);
@@ -8144,18 +8120,10 @@ s390_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
set_gdbarch_frame_align (gdbarch, s390_frame_align);
set_gdbarch_return_value (gdbarch, s390_return_value);

- /* Syscall handling. */
- set_gdbarch_get_syscall_number (gdbarch, s390_linux_get_syscall_number);
-
/* Frame handling. */
dwarf2_frame_set_init_reg (gdbarch, s390_dwarf2_frame_init_reg);
dwarf2_frame_set_adjust_regnum (gdbarch, s390_adjust_frame_regnum);
- dwarf2_append_unwinders (gdbarch);
frame_base_append_sniffer (gdbarch, dwarf2_frame_base_sniffer);
- frame_unwind_append_unwinder (gdbarch, &s390_stub_frame_unwind);
- frame_unwind_append_unwinder (gdbarch, &s390_sigtramp_frame_unwind);
- frame_unwind_append_unwinder (gdbarch, &s390_frame_unwind);
- frame_base_set_default (gdbarch, &s390_frame_base);
set_gdbarch_unwind_pc (gdbarch, s390_unwind_pc);
set_gdbarch_unwind_sp (gdbarch, s390_unwind_sp);

@@ -8166,65 +8134,118 @@ s390_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
set_gdbarch_displaced_step_location (gdbarch, linux_displaced_step_location);
set_gdbarch_max_insn_length (gdbarch, S390_MAX_INSTR_SIZE);

- /* Note that GNU/Linux is the only OS supported on this
- platform. */
- linux_init_abi (info, gdbarch);
-
switch (tdep->abi)
{
case ABI_LINUX_S390:
set_gdbarch_addr_bits_remove (gdbarch, s390_addr_bits_remove);
- set_solib_svr4_fetch_link_map_offsets
- (gdbarch, svr4_ilp32_fetch_link_map_offsets);
-
- set_xml_syscall_file_name (gdbarch, XML_SYSCALL_FILENAME_S390);
break;

case ABI_LINUX_ZSERIES:
set_gdbarch_long_bit (gdbarch, 64);
set_gdbarch_long_long_bit (gdbarch, 64);
set_gdbarch_ptr_bit (gdbarch, 64);
- set_solib_svr4_fetch_link_map_offsets
- (gdbarch, svr4_lp64_fetch_link_map_offsets);
set_gdbarch_address_class_type_flags (gdbarch,
s390_address_class_type_flags);
set_gdbarch_address_class_type_flags_to_name (gdbarch,
s390_address_class_type_flags_to_name);
set_gdbarch_address_class_name_to_type_flags (gdbarch,
s390_address_class_name_to_type_flags);
- set_xml_syscall_file_name (gdbarch, XML_SYSCALL_FILENAME_S390X);
break;
}

- set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
-
- /* Enable TLS support. */
- set_gdbarch_fetch_tls_load_module_address (gdbarch,
- svr4_fetch_objfile_link_map);
-
/* SystemTap functions. */
set_gdbarch_stap_register_prefixes (gdbarch, stap_register_prefixes);
set_gdbarch_stap_register_indirection_prefixes (gdbarch,
stap_register_indirection_prefixes);
set_gdbarch_stap_register_indirection_suffixes (gdbarch,
stap_register_indirection_suffixes);
- set_gdbarch_stap_is_single_operand (gdbarch, s390_stap_is_single_operand);
- set_gdbarch_gcc_target_options (gdbarch, s390_gcc_target_options);
- set_gdbarch_gnu_triplet_regexp (gdbarch, s390_gnu_triplet_regexp);

- /* Support reverse debugging. */
+ set_gdbarch_disassembler_options (gdbarch, &s390_disassembler_options);
+ set_gdbarch_valid_disassembler_options (gdbarch,
+ disassembler_options_s390 ());
+
+ return gdbarch;
+}
+
+/* Initialize OSABI common for GNU/Linux on 31- and 64-bit systems. */
+
+static void
+s390_linux_init_abi_any (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ linux_init_abi (info, gdbarch);

+ /* Register handling. */
+ set_gdbarch_core_read_description (gdbarch, s390_core_read_description);
+ set_gdbarch_iterate_over_regset_sections (gdbarch,
+ s390_iterate_over_regset_sections);
+ set_gdbarch_guess_tracepoint_registers (gdbarch,
+ s390_guess_tracepoint_registers);
+ set_gdbarch_write_pc (gdbarch, s390_write_pc);
+
+ /* Syscall handling. */
+ set_gdbarch_get_syscall_number (gdbarch, s390_linux_get_syscall_number);
+
+ /* Frame handling. */
+ frame_unwind_append_unwinder (gdbarch, &s390_stub_frame_unwind);
+ frame_unwind_append_unwinder (gdbarch, &s390_sigtramp_frame_unwind);
+ frame_unwind_append_unwinder (gdbarch, &s390_frame_unwind);
+ frame_base_set_default (gdbarch, &s390_frame_base);
+ set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
+
+ /* Enable TLS support. */
+ set_gdbarch_fetch_tls_load_module_address (gdbarch,
+ svr4_fetch_objfile_link_map);
+
+ /* Support reverse debugging. */
set_gdbarch_process_record (gdbarch, s390_process_record);
set_gdbarch_process_record_signal (gdbarch, s390_linux_record_signal);
-
s390_init_linux_record_tdep (&s390_linux_record_tdep, ABI_LINUX_S390);
s390_init_linux_record_tdep (&s390x_linux_record_tdep, ABI_LINUX_ZSERIES);

- set_gdbarch_disassembler_options (gdbarch, &s390_disassembler_options);
- set_gdbarch_valid_disassembler_options (gdbarch,
- disassembler_options_s390 ());
+ /* Miscellaneous. */
+ set_gdbarch_stap_is_single_operand (gdbarch, s390_stap_is_single_operand);
+ set_gdbarch_gcc_target_options (gdbarch, s390_gcc_target_options);
+ set_gdbarch_gnu_triplet_regexp (gdbarch, s390_gnu_triplet_regexp);
+}

- return gdbarch;
+/* Initialize OSABI for GNU/Linux on 31-bit systems. */
+
+static void
+s390_linux_init_abi_31 (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ const struct target_desc *tdesc = info.target_desc;
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ tdep->abi = ABI_LINUX_S390;
+ if (!tdesc_has_registers (tdesc))
+ tdesc = tdesc_s390_linux32;
+ tdep->tdesc = tdesc;
+
+ s390_linux_init_abi_any (info, gdbarch);
+
+ set_solib_svr4_fetch_link_map_offsets (gdbarch,
+ svr4_ilp32_fetch_link_map_offsets);
+ set_xml_syscall_file_name (gdbarch, XML_SYSCALL_FILENAME_S390);
+}
+
+/* Initialize OSABI for GNU/Linux on 64-bit systems. */
+
+static void
+s390_linux_init_abi_64 (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+ const struct target_desc *tdesc = info.target_desc;
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ tdep->abi = ABI_LINUX_ZSERIES;
+ if (!tdesc_has_registers (tdesc))
+ tdesc = tdesc_s390x_linux64;
+ tdep->tdesc = tdesc;
+
+ s390_linux_init_abi_any (info, gdbarch);
+
+ set_solib_svr4_fetch_link_map_offsets (gdbarch,
+ svr4_lp64_fetch_link_map_offsets);
+ set_xml_syscall_file_name (gdbarch, XML_SYSCALL_FILENAME_S390X);
}

void
@@ -8233,6 +8254,12 @@ _initialize_s390_tdep (void)
/* Hook us into the gdbarch mechanism. */
register_gdbarch_init (bfd_arch_s390, s390_gdbarch_init);

+ /* Hook us into the OSABI mechanism. */
+ gdbarch_register_osabi (bfd_arch_s390, bfd_mach_s390_31, GDB_OSABI_LINUX,
+ s390_linux_init_abi_31);
+ gdbarch_register_osabi (bfd_arch_s390, bfd_mach_s390_64, GDB_OSABI_LINUX,
+ s390_linux_init_abi_64);
+
/* Initialize the GNU/Linux target descriptions. */
initialize_tdesc_s390_linux32 ();
initialize_tdesc_s390_linux32v1 ();
--
2.13.5