/* 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 "doublest.h"
+#include "floatformat.h"
#include "frame.h"
#include "target.h"
#include "gdb_string.h"
#include "gdbtypes.h"
#include "osabi.h"
+#include "regcache.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. */
+
+#define M68K_LINUX_JB_ELEMENT_SIZE 4
+#define M68K_LINUX_JB_PC 7
+
/* Check whether insn1 and insn2 are parts of a signal trampoline. */
#define IS_SIGTRAMP(insn1, insn2) \
/* 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_frame_saved_pc we also distinguish between non-RT and RT
- signal trampolines. */
+/* 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. */
-int
-m68k_linux_in_sigtramp (CORE_ADDR pc)
+static int
+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))
return 0;
}
-/* Offset to saved PC in sigcontext, from <asm/sigcontext.h>. */
-#define SIGCONTEXT_PC_OFFSET 26
-
-/* Offset to saved PC in ucontext, from <asm/ucontext.h>. */
-#define UCONTEXT_PC_OFFSET 88
-
-/* Get saved user PC for sigtramp from sigcontext or ucontext. */
-
-static CORE_ADDR
-m68k_linux_sigtramp_saved_pc (struct frame_info *frame)
+/* From <asm/sigcontext.h>. */
+static int m68k_linux_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 */
+ -1, /* %a5 */
+ -1, /* %fp */
+ 1 * 4, /* %sp */
+ 6 * 4, /* %sr */
+ 6 * 4 + 2, /* %pc */
+ 8 * 4, /* %fp0 */
+ 11 * 4, /* %fp1 */
+ -1, /* %fp2 */
+ -1, /* %fp3 */
+ -1, /* %fp4 */
+ -1, /* %fp5 */
+ -1, /* %fp6 */
+ -1, /* %fp7 */
+ 14 * 4, /* %fpcr */
+ 15 * 4, /* %fpsr */
+ 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] =
+{
+ 6 * 4, /* %d0 */
+ 7 * 4, /* %d1 */
+ 8 * 4, /* %d2 */
+ 9 * 4, /* %d3 */
+ 10 * 4, /* %d4 */
+ 11 * 4, /* %d5 */
+ 12 * 4, /* %d6 */
+ 13 * 4, /* %d7 */
+ 14 * 4, /* %a0 */
+ 15 * 4, /* %a1 */
+ 16 * 4, /* %a2 */
+ 17 * 4, /* %a3 */
+ 18 * 4, /* %a4 */
+ 19 * 4, /* %a5 */
+ 20 * 4, /* %fp */
+ 21 * 4, /* %sp */
+ 23 * 4, /* %sr */
+ 22 * 4, /* %pc */
+ 27 * 4, /* %fp0 */
+ 30 * 4, /* %fp1 */
+ 33 * 4, /* %fp2 */
+ 36 * 4, /* %fp3 */
+ 39 * 4, /* %fp4 */
+ 42 * 4, /* %fp5 */
+ 45 * 4, /* %fp6 */
+ 48 * 4, /* %fp7 */
+ 24 * 4, /* %fpcr */
+ 25 * 4, /* %fpsr */
+ 26 * 4 /* %fpiaddr */
+};
+
+
+/* Get info about saved registers in sigtramp. */
+
+struct m68k_linux_sigtramp_info
+{
+ /* Address of sigcontext. */
CORE_ADDR sigcontext_addr;
- char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
- int ptrbytes = TARGET_PTR_BIT / TARGET_CHAR_BIT;
- int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT;
- /* Get sigcontext address, it is the third parameter on the stack. */
- if (get_next_frame (frame))
- sigcontext_addr
- = read_memory_unsigned_integer (get_frame_base (get_next_frame (frame))
- + FRAME_ARGS_SKIP
- + sigcontext_offs,
- ptrbytes);
- else
- sigcontext_addr
- = read_memory_unsigned_integer (read_register (SP_REGNUM)
- + sigcontext_offs,
- ptrbytes);
-
- /* Don't cause a memory_error when accessing sigcontext in case the
- stack layout has changed or the stack is corrupt. */
- if (m68k_linux_in_sigtramp (get_frame_pc (frame)) == 2)
- target_read_memory (sigcontext_addr + UCONTEXT_PC_OFFSET, buf, ptrbytes);
- else
- target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, ptrbytes);
- return extract_unsigned_integer (buf, ptrbytes);
-}
+ /* Offset of registers in `struct sigcontext'. */
+ int *sc_reg_offset;
+};
-/* Return the saved program counter for FRAME. */
+/* Nonzero if running on uClinux. */
+static int target_is_uclinux;
-static CORE_ADDR
-m68k_linux_frame_saved_pc (struct frame_info *frame)
+static void
+m68k_linux_inferior_created (struct target_ops *objfile, int from_tty)
{
- if (get_frame_type (frame) == SIGTRAMP_FRAME)
- return m68k_linux_sigtramp_saved_pc (frame);
-
- return read_memory_unsigned_integer (get_frame_base (frame) + 4, 4);
+ /* 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;
}
-/* The following definitions are appropriate when using the ELF
- format, where floating point values are returned in fp0, pointer
- values in a0 and other values in d0. */
-
-/* Extract from an array REGBUF containing the (raw) register state a
- function return value of type TYPE, and copy that, in virtual
- format, into VALBUF. */
-
-static void
-m68k_linux_extract_return_value (struct type *type, char *regbuf, char *valbuf)
+static struct m68k_linux_sigtramp_info
+m68k_linux_get_sigtramp_info (struct frame_info *this_frame)
{
- if (TYPE_CODE (type) == TYPE_CODE_FLT)
+ 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 (target_is_uclinux == -1)
{
- REGISTER_CONVERT_TO_VIRTUAL (FP0_REGNUM, type,
- regbuf + REGISTER_BYTE (FP0_REGNUM),
- valbuf);
+ /* Determine whether we are running on a uClinux or normal GNU/Linux
+ target so we can use the correct sigcontext layouts. */
+ CORE_ADDR dummy;
+
+ 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)
- memcpy (valbuf, regbuf + REGISTER_BYTE (M68K_A0_REGNUM),
- TYPE_LENGTH (type));
+
+ 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
- memcpy (valbuf,
- regbuf + (TYPE_LENGTH (type) >= 4 ? 0 : 4 - TYPE_LENGTH (type)),
- TYPE_LENGTH (type));
+ info.sc_reg_offset = (target_is_uclinux
+ ? m68k_uclinux_sigcontext_reg_offset
+ : m68k_linux_sigcontext_reg_offset);
+ return info;
}
-/* Write into appropriate registers a function return value of type
- TYPE, given in virtual format. */
+/* Signal trampolines. */
+
+static struct trad_frame_cache *
+m68k_linux_sigtramp_frame_cache (struct frame_info *this_frame,
+ void **this_cache)
+{
+ 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;
+}
static void
-m68k_linux_store_return_value (struct type *type, char *valbuf)
+m68k_linux_sigtramp_frame_this_id (struct frame_info *this_frame,
+ void **this_cache,
+ struct frame_id *this_id)
{
- if (TYPE_CODE (type) == TYPE_CODE_FLT)
- {
- char raw_buffer[REGISTER_RAW_SIZE (FP0_REGNUM)];
- REGISTER_CONVERT_TO_RAW (type, FP0_REGNUM, valbuf, raw_buffer);
- deprecated_write_register_bytes (REGISTER_BYTE (FP0_REGNUM),
- raw_buffer, TYPE_LENGTH (type));
- }
- else
- {
- if (TYPE_CODE (type) == TYPE_CODE_PTR)
- deprecated_write_register_bytes (REGISTER_BYTE (M68K_A0_REGNUM),
- valbuf, TYPE_LENGTH (type));
- deprecated_write_register_bytes (0, valbuf, TYPE_LENGTH (type));
- }
+ struct trad_frame_cache *cache =
+ m68k_linux_sigtramp_frame_cache (this_frame, this_cache);
+ trad_frame_get_id (cache, this_id);
}
-/* 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 struct value *
+m68k_linux_sigtramp_frame_prev_register (struct frame_info *this_frame,
+ void **this_cache,
+ int regnum)
+{
+ /* 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);
+}
-static CORE_ADDR
-m68k_linux_extract_struct_value_address (char *regbuf)
+static int
+m68k_linux_sigtramp_frame_sniffer (const struct frame_unwind *self,
+ struct frame_info *this_frame,
+ void **this_prologue_cache)
{
- return *(CORE_ADDR *) (regbuf + REGISTER_BYTE (M68K_A0_REGNUM));
+ 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)
{
- set_gdbarch_deprecated_frame_saved_pc (gdbarch,
- m68k_linux_frame_saved_pc);
- set_gdbarch_deprecated_extract_return_value (gdbarch,
- m68k_linux_extract_return_value);
- set_gdbarch_deprecated_store_return_value (gdbarch,
- m68k_linux_store_return_value);
- set_gdbarch_deprecated_extract_struct_value_address (gdbarch,
- m68k_linux_extract_struct_value_address);
+ struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+ tdep->jb_pc = M68K_LINUX_JB_PC;
+ tdep->jb_elt_size = M68K_LINUX_JB_ELEMENT_SIZE;
+
+ /* 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_decr_pc_after_break (gdbarch, 2);
+
+ frame_unwind_append_unwinder (gdbarch, &m68k_linux_sigtramp_frame_unwind);
+
+ /* Shared library handling. */
+
+ /* 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);
}