c481dac737
(struct gdbarch_tdep): Add struct_return. * m68k-tdep.c (m68k_push_dummy_call): Non-scalars bigger than 4 bytes are padded to the right, not to the left. Pass struct value address in register %a1, not on stack. (m68k_use_struct_convention): New function. (m68k_gdbarch_init): Set use_struct_convention. Initialize struct_return in tdep to pcc_struct_return. * m68klinux-tdep.c (m68k_linux_init_abi): Set struct_return to reg_struct_return.
313 lines
8.5 KiB
C
313 lines
8.5 KiB
C
/* Motorola m68k target-dependent support for GNU/Linux.
|
||
|
||
Copyright 1996, 1998, 2000, 2001, 2002, 2003 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
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
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. */
|
||
|
||
#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"
|
||
|
||
/* 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) \
|
||
(/* addaw #20,sp; moveq #119,d0; trap #0 */ \
|
||
(insn1 == 0xdefc0014 && insn2 == 0x70774e40) \
|
||
/* moveq #119,d0; trap #0 */ \
|
||
|| insn1 == 0x70774e40)
|
||
|
||
#define IS_RT_SIGTRAMP(insn1, insn2) \
|
||
(/* movel #173,d0; trap #0 */ \
|
||
(insn1 == 0x203c0000 && insn2 == 0x00ad4e40) \
|
||
/* 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
|
||
non-RT and RT signal trampolines. */
|
||
|
||
static int
|
||
m68k_linux_pc_in_sigtramp (CORE_ADDR pc, char *name)
|
||
{
|
||
CORE_ADDR sp;
|
||
char buf[12];
|
||
unsigned long insn0, insn1, insn2;
|
||
|
||
if (read_memory_nobpt (pc - 4, buf, sizeof (buf)))
|
||
return 0;
|
||
insn1 = extract_unsigned_integer (buf + 4, 4);
|
||
insn2 = extract_unsigned_integer (buf + 8, 4);
|
||
if (IS_SIGTRAMP (insn1, insn2))
|
||
return 1;
|
||
if (IS_RT_SIGTRAMP (insn1, insn2))
|
||
return 2;
|
||
|
||
insn0 = extract_unsigned_integer (buf, 4);
|
||
if (IS_SIGTRAMP (insn0, insn1))
|
||
return 1;
|
||
if (IS_RT_SIGTRAMP (insn0, insn1))
|
||
return 2;
|
||
|
||
insn0 = ((insn0 << 16) & 0xffffffff) | (insn1 >> 16);
|
||
insn1 = ((insn1 << 16) & 0xffffffff) | (insn2 >> 16);
|
||
if (IS_SIGTRAMP (insn0, insn1))
|
||
return 1;
|
||
if (IS_RT_SIGTRAMP (insn0, insn1))
|
||
return 2;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* 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 */
|
||
5 * 4 + 2, /* %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 */
|
||
};
|
||
|
||
/* 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. */
|
||
|
||
static struct m68k_sigtramp_info
|
||
m68k_linux_get_sigtramp_info (struct frame_info *next_frame)
|
||
{
|
||
CORE_ADDR sp;
|
||
char buf[4];
|
||
struct m68k_sigtramp_info info;
|
||
|
||
frame_unwind_register (next_frame, M68K_SP_REGNUM, buf);
|
||
sp = extract_unsigned_integer (buf, 4);
|
||
|
||
/* Get sigcontext address, it is the third parameter on the stack. */
|
||
info.sigcontext_addr = read_memory_unsigned_integer (sp + 8, 4);
|
||
|
||
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;
|
||
}
|
||
|
||
/* 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)
|
||
{
|
||
int len = TYPE_LENGTH (type);
|
||
char buf[M68K_MAX_REGISTER_SIZE];
|
||
|
||
if (TYPE_CODE (type) == TYPE_CODE_STRUCT
|
||
&& TYPE_NFIELDS (type) == 1)
|
||
{
|
||
m68k_linux_extract_return_value (TYPE_FIELD_TYPE (type, 0), regcache,
|
||
valbuf);
|
||
return;
|
||
}
|
||
|
||
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);
|
||
}
|
||
else if (TYPE_CODE (type) == TYPE_CODE_PTR)
|
||
regcache_raw_read (regcache, M68K_A0_REGNUM, valbuf);
|
||
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);
|
||
}
|
||
}
|
||
|
||
/* Write into the appropriate registers a function return value stored
|
||
in VALBUF of type TYPE, given in virtual format. */
|
||
|
||
static void
|
||
m68k_linux_store_return_value (struct type *type, struct regcache *regcache,
|
||
const void *valbuf)
|
||
{
|
||
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);
|
||
}
|
||
}
|
||
|
||
/* 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 CORE_ADDR
|
||
m68k_linux_extract_struct_value_address (struct regcache *regcache)
|
||
{
|
||
char buf[4];
|
||
|
||
regcache_cooked_read (regcache, M68K_A0_REGNUM, buf);
|
||
return extract_unsigned_integer (buf, 4);
|
||
}
|
||
|
||
static void
|
||
m68k_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
struct gdbarch_tdep *tdep = gdbarch_tdep (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;
|
||
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_pc_in_sigtramp (gdbarch, m68k_linux_pc_in_sigtramp);
|
||
|
||
/* Shared library handling. */
|
||
set_gdbarch_in_solib_call_trampoline (gdbarch, in_plt_section);
|
||
set_gdbarch_skip_trampoline_code (gdbarch, find_solib_trampoline_target);
|
||
}
|
||
|
||
void
|
||
_initialize_m68k_linux_tdep (void)
|
||
{
|
||
gdbarch_register_osabi (bfd_arch_m68k, 0, GDB_OSABI_LINUX,
|
||
m68k_linux_init_abi);
|
||
}
|