/* Motorola m68k target-dependent support for GNU/Linux.
- Copyright 1996, 1998, 2000, 2001, 2002, 2003 Free Software Foundation,
- Inc.
+ Copyright (C) 1996, 1998, 2000, 2001, 2002, 2003, 2004, 2007, 2008, 2009,
+ 2010 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "gdbcore.h"
#include "objfiles.h"
#include "symtab.h"
#include "m68k-tdep.h"
+#include "trad-frame.h"
+#include "frame-unwind.h"
+#include "glibc-tdep.h"
+#include "solib-svr4.h"
+#include "auxv.h"
+#include "observer.h"
+#include "elf/common.h"
\f
/* Offsets (in target ints) into jmp_buf. */
/* moveq #82,d0; notb d0; trap #0 */ \
|| (insn1 == 0x70524600 && (insn2 >> 16) == 0x4e40))
-/* Return non-zero if PC points into the signal trampoline. For the
- sake of m68k_linux_get_sigtramp_info we also distinguish between
+/* Return non-zero if THIS_FRAME corresponds to a signal trampoline. For
+ the sake of m68k_linux_get_sigtramp_info we also distinguish between
non-RT and RT signal trampolines. */
static int
-m68k_linux_pc_in_sigtramp (CORE_ADDR pc, char *name)
+m68k_linux_pc_in_sigtramp (struct frame_info *this_frame)
{
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
CORE_ADDR sp;
- char buf[12];
+ gdb_byte buf[12];
unsigned long insn0, insn1, insn2;
+ CORE_ADDR pc = get_frame_pc (this_frame);
- if (read_memory_nobpt (pc - 4, buf, sizeof (buf)))
+ if (!safe_frame_unwind_memory (this_frame, pc - 4, buf, sizeof (buf)))
return 0;
- insn1 = extract_unsigned_integer (buf + 4, 4);
- insn2 = extract_unsigned_integer (buf + 8, 4);
+ insn1 = extract_unsigned_integer (buf + 4, 4, byte_order);
+ insn2 = extract_unsigned_integer (buf + 8, 4, byte_order);
if (IS_SIGTRAMP (insn1, insn2))
return 1;
if (IS_RT_SIGTRAMP (insn1, insn2))
return 2;
- insn0 = extract_unsigned_integer (buf, 4);
+ insn0 = extract_unsigned_integer (buf, 4, byte_order);
if (IS_SIGTRAMP (insn0, insn1))
return 1;
if (IS_RT_SIGTRAMP (insn0, insn1))
-1, /* %a5 */
-1, /* %fp */
1 * 4, /* %sp */
- 5 * 4 + 2, /* %sr */
+ 6 * 4, /* %sr */
6 * 4 + 2, /* %pc */
8 * 4, /* %fp0 */
11 * 4, /* %fp1 */
16 * 4 /* %fpiaddr */
};
+static int m68k_uclinux_sigcontext_reg_offset[M68K_NUM_REGS] =
+{
+ 2 * 4, /* %d0 */
+ 3 * 4, /* %d1 */
+ -1, /* %d2 */
+ -1, /* %d3 */
+ -1, /* %d4 */
+ -1, /* %d5 */
+ -1, /* %d6 */
+ -1, /* %d7 */
+ 4 * 4, /* %a0 */
+ 5 * 4, /* %a1 */
+ -1, /* %a2 */
+ -1, /* %a3 */
+ -1, /* %a4 */
+ 6 * 4, /* %a5 */
+ -1, /* %fp */
+ 1 * 4, /* %sp */
+ 7 * 4, /* %sr */
+ 7 * 4 + 2, /* %pc */
+ -1, /* %fp0 */
+ -1, /* %fp1 */
+ -1, /* %fp2 */
+ -1, /* %fp3 */
+ -1, /* %fp4 */
+ -1, /* %fp5 */
+ -1, /* %fp6 */
+ -1, /* %fp7 */
+ -1, /* %fpcr */
+ -1, /* %fpsr */
+ -1 /* %fpiaddr */
+};
+
/* From <asm/ucontext.h>. */
static int m68k_linux_ucontext_reg_offset[M68K_NUM_REGS] =
{
/* Get info about saved registers in sigtramp. */
-static struct m68k_sigtramp_info
-m68k_linux_get_sigtramp_info (struct frame_info *next_frame)
+struct m68k_linux_sigtramp_info
{
- CORE_ADDR sp;
- char buf[4];
- struct m68k_sigtramp_info info;
+ /* Address of sigcontext. */
+ CORE_ADDR sigcontext_addr;
- frame_unwind_register (next_frame, M68K_SP_REGNUM, buf);
- sp = extract_unsigned_integer (buf, 4);
+ /* Offset of registers in `struct sigcontext'. */
+ int *sc_reg_offset;
+};
- /* Get sigcontext address, it is the third parameter on the stack. */
- info.sigcontext_addr = read_memory_unsigned_integer (sp + 8, 4);
+/* Nonzero if running on uClinux. */
+static int target_is_uclinux;
- if (m68k_linux_pc_in_sigtramp (frame_pc_unwind (next_frame), 0) == 2)
- info.sc_reg_offset = m68k_linux_ucontext_reg_offset;
- else
- info.sc_reg_offset = m68k_linux_sigcontext_reg_offset;
- return info;
+static void
+m68k_linux_inferior_created (struct target_ops *objfile, int from_tty)
+{
+ /* Record that we will need to re-evaluate whether we are running on a
+ uClinux or normal GNU/Linux target (see m68k_linux_get_sigtramp_info). */
+ target_is_uclinux = -1;
}
-/* Extract from an array REGBUF containing the (raw) register state, a
- function return value of TYPE, and copy that, in virtual format,
- into VALBUF. */
-
-static void
-m68k_linux_extract_return_value (struct type *type, struct regcache *regcache,
- void *valbuf)
+static struct m68k_linux_sigtramp_info
+m68k_linux_get_sigtramp_info (struct frame_info *this_frame)
{
- int len = TYPE_LENGTH (type);
- char buf[M68K_MAX_REGISTER_SIZE];
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ CORE_ADDR sp;
+ struct m68k_linux_sigtramp_info info;
- if (TYPE_CODE (type) == TYPE_CODE_STRUCT
- && TYPE_NFIELDS (type) == 1)
+ if (target_is_uclinux == -1)
{
- m68k_linux_extract_return_value (TYPE_FIELD_TYPE (type, 0), regcache,
- valbuf);
- return;
- }
+ /* Determine whether we are running on a uClinux or normal GNU/Linux
+ target so we can use the correct sigcontext layouts. */
+ CORE_ADDR dummy;
- if (TYPE_CODE (type) == TYPE_CODE_FLT)
- {
- regcache_raw_read (regcache, M68K_FP0_REGNUM, buf);
- convert_typed_floating (buf, builtin_type_m68881_ext, valbuf, type);
+ target_is_uclinux
+ = (target_auxv_search (¤t_target, AT_NULL, &dummy) > 0
+ && target_auxv_search (¤t_target, AT_PAGESZ, &dummy) == 0);
}
- else if (TYPE_CODE (type) == TYPE_CODE_PTR)
- regcache_raw_read (regcache, M68K_A0_REGNUM, valbuf);
+
+ sp = get_frame_register_unsigned (this_frame, M68K_SP_REGNUM);
+
+ /* Get sigcontext address, it is the third parameter on the stack. */
+ info.sigcontext_addr = read_memory_unsigned_integer (sp + 8, 4, byte_order);
+
+ if (m68k_linux_pc_in_sigtramp (this_frame) == 2)
+ info.sc_reg_offset = m68k_linux_ucontext_reg_offset;
else
- {
- if (len <= 4)
- {
- regcache_raw_read (regcache, M68K_D0_REGNUM, buf);
- memcpy (valbuf, buf + (4 - len), len);
- }
- else if (len <= 8)
- {
- regcache_raw_read (regcache, M68K_D0_REGNUM, buf);
- memcpy (valbuf, buf + (8 - len), len - 4);
- regcache_raw_read (regcache, M68K_D1_REGNUM,
- (char *) valbuf + (len - 4));
- }
- else
- internal_error (__FILE__, __LINE__,
- "Cannot extract return value of %d bytes long.", len);
- }
+ info.sc_reg_offset = (target_is_uclinux
+ ? m68k_uclinux_sigcontext_reg_offset
+ : m68k_linux_sigcontext_reg_offset);
+ return info;
}
-/* Write into the appropriate registers a function return value stored
- in VALBUF of type TYPE, given in virtual format. */
+/* Signal trampolines. */
-static void
-m68k_linux_store_return_value (struct type *type, struct regcache *regcache,
- const void *valbuf)
+static struct trad_frame_cache *
+m68k_linux_sigtramp_frame_cache (struct frame_info *this_frame,
+ void **this_cache)
{
- int len = TYPE_LENGTH (type);
-
- if (TYPE_CODE (type) == TYPE_CODE_STRUCT
- && TYPE_NFIELDS (type) == 1)
- {
- m68k_linux_store_return_value (TYPE_FIELD_TYPE (type, 0), regcache,
- valbuf);
- return;
- }
-
- if (TYPE_CODE (type) == TYPE_CODE_FLT)
- {
- char buf[M68K_MAX_REGISTER_SIZE];
- convert_typed_floating (valbuf, type, buf, builtin_type_m68881_ext);
- regcache_raw_write (regcache, M68K_FP0_REGNUM, buf);
- }
- else if (TYPE_CODE (type) == TYPE_CODE_PTR)
- regcache_raw_write (regcache, M68K_A0_REGNUM, valbuf);
- else
- {
- if (len <= 4)
- regcache_raw_write_part (regcache, M68K_D0_REGNUM,
- 4 - len, len, valbuf);
- else if (len <= 8)
- {
- regcache_raw_write_part (regcache, M68K_D1_REGNUM, 8 - len,
- len - 4, valbuf);
- regcache_raw_write (regcache, M68K_D0_REGNUM,
- (char *) valbuf + (len - 4));
- }
- else
- internal_error (__FILE__, __LINE__,
- "Cannot store return value of %d bytes long.", len);
- }
+ struct frame_id this_id;
+ struct trad_frame_cache *cache;
+ struct gdbarch *gdbarch = get_frame_arch (this_frame);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+ enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+ struct m68k_linux_sigtramp_info info;
+ gdb_byte buf[4];
+ int i;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = trad_frame_cache_zalloc (this_frame);
+
+ /* FIXME: cagney/2004-05-01: This is is long standing broken code.
+ The frame ID's code address should be the start-address of the
+ signal trampoline and not the current PC within that
+ trampoline. */
+ get_frame_register (this_frame, M68K_SP_REGNUM, buf);
+ /* See the end of m68k_push_dummy_call. */
+ this_id = frame_id_build (extract_unsigned_integer (buf, 4, byte_order)
+ - 4 + 8, get_frame_pc (this_frame));
+ trad_frame_set_id (cache, this_id);
+
+ info = m68k_linux_get_sigtramp_info (this_frame);
+
+ for (i = 0; i < M68K_NUM_REGS; i++)
+ if (info.sc_reg_offset[i] != -1)
+ trad_frame_set_reg_addr (cache, i,
+ info.sigcontext_addr + info.sc_reg_offset[i]);
+
+ *this_cache = cache;
+ return cache;
}
-/* Extract from an array REGBUF containing the (raw) register state
- the address in which a function should return its structure value,
- as a CORE_ADDR. */
+static void
+m68k_linux_sigtramp_frame_this_id (struct frame_info *this_frame,
+ void **this_cache,
+ struct frame_id *this_id)
+{
+ struct trad_frame_cache *cache =
+ m68k_linux_sigtramp_frame_cache (this_frame, this_cache);
+ trad_frame_get_id (cache, this_id);
+}
-static CORE_ADDR
-m68k_linux_extract_struct_value_address (struct regcache *regcache)
+static struct value *
+m68k_linux_sigtramp_frame_prev_register (struct frame_info *this_frame,
+ void **this_cache,
+ int regnum)
{
- char buf[4];
+ /* Make sure we've initialized the cache. */
+ struct trad_frame_cache *cache =
+ m68k_linux_sigtramp_frame_cache (this_frame, this_cache);
+ return trad_frame_get_register (cache, this_frame, regnum);
+}
- regcache_cooked_read (regcache, M68K_A0_REGNUM, buf);
- return extract_unsigned_integer (buf, 4);
+static int
+m68k_linux_sigtramp_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_prologue_cache)
+{
+ return m68k_linux_pc_in_sigtramp (this_frame);
}
+static const struct frame_unwind m68k_linux_sigtramp_frame_unwind =
+{
+ SIGTRAMP_FRAME,
+ m68k_linux_sigtramp_frame_this_id,
+ m68k_linux_sigtramp_frame_prev_register,
+ NULL,
+ m68k_linux_sigtramp_frame_sniffer
+};
+
static void
m68k_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
{
tdep->jb_pc = M68K_LINUX_JB_PC;
tdep->jb_elt_size = M68K_LINUX_JB_ELEMENT_SIZE;
- tdep->get_sigtramp_info = m68k_linux_get_sigtramp_info;
+
+ /* GNU/Linux uses a calling convention that's similar to SVR4. It
+ returns integer values in %d0/%d1, pointer values in %a0 and
+ floating values in %fp0, just like SVR4, but uses %a1 to pass the
+ address to store a structure value. It also returns small
+ structures in registers instead of memory. */
+ m68k_svr4_init_abi (info, gdbarch);
+ tdep->struct_value_regnum = M68K_A1_REGNUM;
tdep->struct_return = reg_struct_return;
- set_gdbarch_extract_return_value (gdbarch, m68k_linux_extract_return_value);
- set_gdbarch_store_return_value (gdbarch, m68k_linux_store_return_value);
- set_gdbarch_extract_struct_value_address (gdbarch,
- m68k_linux_extract_struct_value_address);
+ set_gdbarch_decr_pc_after_break (gdbarch, 2);
- set_gdbarch_pc_in_sigtramp (gdbarch, m68k_linux_pc_in_sigtramp);
+ frame_unwind_append_unwinder (gdbarch, &m68k_linux_sigtramp_frame_unwind);
/* Shared library handling. */
- set_gdbarch_in_solib_call_trampoline (gdbarch, in_plt_section);
+
+ /* GNU/Linux uses SVR4-style shared libraries. */
+ set_solib_svr4_fetch_link_map_offsets (gdbarch,
+ svr4_ilp32_fetch_link_map_offsets);
+
+ /* GNU/Linux uses the dynamic linker included in the GNU C Library. */
+ set_gdbarch_skip_solib_resolver (gdbarch, glibc_skip_solib_resolver);
+
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);
}
+/* Provide a prototype to silence -Wmissing-prototypes. */
+extern initialize_file_ftype _initialize_m68k_linux_tdep;
+
void
_initialize_m68k_linux_tdep (void)
{
gdbarch_register_osabi (bfd_arch_m68k, 0, GDB_OSABI_LINUX,
m68k_linux_init_abi);
+ observer_attach_inferior_created (m68k_linux_inferior_created);
}