binutils-gdb/gdb/m68k-tdep.c

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/* Target dependent code for the Motorola 68000 series.
Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1999, 2000, 2001
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 "frame.h"
#include "symtab.h"
#include "gdbcore.h"
#include "value.h"
#include "gdb_string.h"
#include "inferior.h"
#include "regcache.h"
#include "arch-utils.h"
#define P_LINKL_FP 0x480e
#define P_LINKW_FP 0x4e56
#define P_PEA_FP 0x4856
#define P_MOVL_SP_FP 0x2c4f
#define P_MOVL 0x207c
#define P_JSR 0x4eb9
#define P_BSR 0x61ff
#define P_LEAL 0x43fb
#define P_MOVML 0x48ef
#define P_FMOVM 0xf237
#define P_TRAP 0x4e40
/* Register numbers of various important registers.
Note that some of these values are "real" register numbers,
and correspond to the general registers of the machine,
and some are "phony" register numbers which are too large
to be actual register numbers as far as the user is concerned
but do serve to get the desired values when passed to read_register. */
/* Note: Since they are used in files other than this (monitor files),
D0_REGNUM and A0_REGNUM are currently defined in tm-m68k.h. */
enum
{
E_A1_REGNUM = 9,
E_FP_REGNUM = 14, /* Contains address of executing stack frame */
E_SP_REGNUM = 15, /* Contains address of top of stack */
E_PS_REGNUM = 16, /* Contains processor status */
E_PC_REGNUM = 17, /* Contains program counter */
E_FP0_REGNUM = 18, /* Floating point register 0 */
E_FPC_REGNUM = 26, /* 68881 control register */
E_FPS_REGNUM = 27, /* 68881 status register */
E_FPI_REGNUM = 28
};
#define REGISTER_BYTES_FP (16*4 + 8 + 8*12 + 3*4)
#define REGISTER_BYTES_NOFP (16*4 + 8)
#define NUM_FREGS (NUM_REGS-24)
/* Offset from SP to first arg on stack at first instruction of a function */
#define SP_ARG0 (1 * 4)
/* This was determined by experimentation on hp300 BSD 4.3. Perhaps
it corresponds to some offset in /usr/include/sys/user.h or
something like that. Using some system include file would
have the advantage of probably being more robust in the face
of OS upgrades, but the disadvantage of being wrong for
cross-debugging. */
#define SIG_PC_FP_OFFSET 530
#define TARGET_M68K
#if !defined (BPT_VECTOR)
#define BPT_VECTOR 0xf
#endif
#if !defined (REMOTE_BPT_VECTOR)
#define REMOTE_BPT_VECTOR 1
#endif
void m68k_frame_init_saved_regs (struct frame_info *frame_info);
/* gdbarch_breakpoint_from_pc is set to m68k_local_breakpoint_from_pc
so m68k_remote_breakpoint_from_pc is currently not used. */
const static unsigned char *
m68k_remote_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
{
static unsigned char break_insn[] = {0x4e, (0x40 | REMOTE_BPT_VECTOR)};
*lenptr = sizeof (break_insn);
return break_insn;
}
const static unsigned char *
m68k_local_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
{
static unsigned char break_insn[] = {0x4e, (0x40 | BPT_VECTOR)};
*lenptr = sizeof (break_insn);
return break_insn;
}
static int
m68k_register_bytes_ok (long numbytes)
{
return ((numbytes == REGISTER_BYTES_FP)
|| (numbytes == REGISTER_BYTES_NOFP));
}
/* Number of bytes of storage in the actual machine representation
for register regnum. On the 68000, all regs are 4 bytes
except the floating point regs which are 12 bytes. */
/* Note that the unsigned cast here forces the result of the
subtraction to very high positive values if regnum < FP0_REGNUM */
static int
m68k_register_raw_size (int regnum)
{
return (((unsigned) (regnum) - FP0_REGNUM) < 8 ? 12 : 4);
}
/* Number of bytes of storage in the program's representation
for register regnum. On the 68000, all regs are 4 bytes
except the floating point regs which are 12-byte long doubles. */
static int
m68k_register_virtual_size (int regnum)
{
return (((unsigned) (regnum) - FP0_REGNUM) < 8 ? 12 : 4);
}
/* Return the GDB type object for the "standard" data type of data
in register N. This should be int for D0-D7, long double for FP0-FP7,
and void pointer for all others (A0-A7, PC, SR, FPCONTROL etc).
Note, for registers which contain addresses return pointer to void,
not pointer to char, because we don't want to attempt to print
the string after printing the address. */
static struct type *
m68k_register_virtual_type (int regnum)
{
if ((unsigned) regnum >= E_FPC_REGNUM)
return lookup_pointer_type (builtin_type_void);
else if ((unsigned) regnum >= FP0_REGNUM)
return builtin_type_long_double;
else if ((unsigned) regnum >= A0_REGNUM)
return lookup_pointer_type (builtin_type_void);
else
return builtin_type_int;
}
/* Function: m68k_register_name
Returns the name of the standard m68k register regnum. */
static const char *
m68k_register_name (int regnum)
{
static char *register_names[] = {
"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7",
"a0", "a1", "a2", "a3", "a4", "a5", "fp", "sp",
"ps", "pc",
"fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7",
"fpcontrol", "fpstatus", "fpiaddr", "fpcode", "fpflags"
};
if (regnum < 0 ||
regnum >= sizeof (register_names) / sizeof (register_names[0]))
internal_error (__FILE__, __LINE__,
"m68k_register_name: illegal register number %d", regnum);
else
return register_names[regnum];
}
/* Stack must be kept short aligned when doing function calls. */
static CORE_ADDR
m68k_stack_align (CORE_ADDR addr)
{
return ((addr + 1) & ~1);
}
/* Index within `registers' of the first byte of the space for
register regnum. */
static int
m68k_register_byte (int regnum)
{
if (regnum >= E_FPC_REGNUM)
return (((regnum - E_FPC_REGNUM) * 4) + 168);
else if (regnum >= FP0_REGNUM)
return (((regnum - FP0_REGNUM) * 12) + 72);
else
return (regnum * 4);
}
/* Store the address of the place in which to copy the structure the
subroutine will return. This is called from call_function. */
static void
m68k_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
{
write_register (E_A1_REGNUM, addr);
}
/* 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. This is assuming that floating point values are returned
as doubles in d0/d1. */
static void
m68k_deprecated_extract_return_value (struct type *type, char *regbuf,
char *valbuf)
{
int offset = 0;
int typeLength = TYPE_LENGTH (type);
if (typeLength < 4)
offset = 4 - typeLength;
memcpy (valbuf, regbuf + offset, typeLength);
}
static CORE_ADDR
m68k_deprecated_extract_struct_value_address (char *regbuf)
{
return (*(CORE_ADDR *) (regbuf));
}
/* Write into appropriate registers a function return value
of type TYPE, given in virtual format. Assumes floats are passed
in d0/d1. */
static void
m68k_store_return_value (struct type *type, char *valbuf)
{
write_register_bytes (0, valbuf, TYPE_LENGTH (type));
}
/* Describe the pointer in each stack frame to the previous stack frame
(its caller). */
/* FRAME_CHAIN takes a frame's nominal address and produces the frame's
chain-pointer.
In the case of the 68000, the frame's nominal address
is the address of a 4-byte word containing the calling frame's address. */
/* If we are chaining from sigtramp, then manufacture a sigtramp frame
(which isn't really on the stack. I'm not sure this is right for anything
but BSD4.3 on an hp300. */
static CORE_ADDR
m68k_frame_chain (struct frame_info *thisframe)
{
if (thisframe->signal_handler_caller)
return thisframe->frame;
else if (!inside_entry_file ((thisframe)->pc))
return read_memory_integer ((thisframe)->frame, 4);
else
return 0;
}
/* A function that tells us whether the function invocation represented
by fi does not have a frame on the stack associated with it. If it
does not, FRAMELESS is set to 1, else 0. */
static int
m68k_frameless_function_invocation (struct frame_info *fi)
{
if (fi->signal_handler_caller)
return 0;
else
return frameless_look_for_prologue (fi);
}
static CORE_ADDR
m68k_frame_saved_pc (struct frame_info *frame)
{
if (frame->signal_handler_caller)
{
if (frame->next)
return read_memory_integer (frame->next->frame + SIG_PC_FP_OFFSET, 4);
else
return read_memory_integer (read_register (SP_REGNUM)
+ SIG_PC_FP_OFFSET - 8, 4);
}
else
return read_memory_integer (frame->frame + 4, 4);
}
/* The only reason this is here is the tm-altos.h reference below. It
was moved back here from tm-m68k.h. FIXME? */
extern CORE_ADDR
altos_skip_prologue (CORE_ADDR pc)
{
register int op = read_memory_integer (pc, 2);
if (op == P_LINKW_FP)
pc += 4; /* Skip link #word */
else if (op == P_LINKL_FP)
pc += 6; /* Skip link #long */
/* Not sure why branches are here. */
/* From tm-altos.h */
else if (op == 0060000)
pc += 4; /* Skip bra #word */
else if (op == 00600377)
pc += 6; /* skip bra #long */
else if ((op & 0177400) == 0060000)
pc += 2; /* skip bra #char */
return pc;
}
int
delta68_in_sigtramp (CORE_ADDR pc, char *name)
{
if (name != NULL)
return strcmp (name, "_sigcode") == 0;
else
return 0;
}
CORE_ADDR
delta68_frame_args_address (struct frame_info *frame_info)
{
/* we assume here that the only frameless functions are the system calls
or other functions who do not put anything on the stack. */
if (frame_info->signal_handler_caller)
return frame_info->frame + 12;
else if (frameless_look_for_prologue (frame_info))
{
/* Check for an interrupted system call */
if (frame_info->next && frame_info->next->signal_handler_caller)
return frame_info->next->frame + 16;
else
return frame_info->frame + 4;
}
else
return frame_info->frame;
}
CORE_ADDR
delta68_frame_saved_pc (struct frame_info *frame_info)
{
return read_memory_integer (delta68_frame_args_address (frame_info) + 4, 4);
}
/* Return number of args passed to a frame.
Can return -1, meaning no way to tell. */
int
isi_frame_num_args (struct frame_info *fi)
{
int val;
CORE_ADDR pc = FRAME_SAVED_PC (fi);
int insn = 0177777 & read_memory_integer (pc, 2);
val = 0;
if (insn == 0047757 || insn == 0157374) /* lea W(sp),sp or addaw #W,sp */
val = read_memory_integer (pc + 2, 2);
else if ((insn & 0170777) == 0050217 /* addql #N, sp */
|| (insn & 0170777) == 0050117) /* addqw */
{
val = (insn >> 9) & 7;
if (val == 0)
val = 8;
}
else if (insn == 0157774) /* addal #WW, sp */
val = read_memory_integer (pc + 2, 4);
val >>= 2;
return val;
}
int
delta68_frame_num_args (struct frame_info *fi)
{
int val;
CORE_ADDR pc = FRAME_SAVED_PC (fi);
int insn = 0177777 & read_memory_integer (pc, 2);
val = 0;
if (insn == 0047757 || insn == 0157374) /* lea W(sp),sp or addaw #W,sp */
val = read_memory_integer (pc + 2, 2);
else if ((insn & 0170777) == 0050217 /* addql #N, sp */
|| (insn & 0170777) == 0050117) /* addqw */
{
val = (insn >> 9) & 7;
if (val == 0)
val = 8;
}
else if (insn == 0157774) /* addal #WW, sp */
val = read_memory_integer (pc + 2, 4);
val >>= 2;
return val;
}
int
news_frame_num_args (struct frame_info *fi)
{
int val;
CORE_ADDR pc = FRAME_SAVED_PC (fi);
int insn = 0177777 & read_memory_integer (pc, 2);
val = 0;
if (insn == 0047757 || insn == 0157374) /* lea W(sp),sp or addaw #W,sp */
val = read_memory_integer (pc + 2, 2);
else if ((insn & 0170777) == 0050217 /* addql #N, sp */
|| (insn & 0170777) == 0050117) /* addqw */
{
val = (insn >> 9) & 7;
if (val == 0)
val = 8;
}
else if (insn == 0157774) /* addal #WW, sp */
val = read_memory_integer (pc + 2, 4);
val >>= 2;
return val;
}
/* Insert the specified number of args and function address
into a call sequence of the above form stored at DUMMYNAME.
We use the BFD routines to store a big-endian value of known size. */
void
m68k_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
struct value **args, struct type *type, int gcc_p)
{
bfd_putb32 (fun, (unsigned char *) dummy + CALL_DUMMY_START_OFFSET + 2);
bfd_putb32 (nargs * 4,
(unsigned char *) dummy + CALL_DUMMY_START_OFFSET + 8);
}
/* Push an empty stack frame, to record the current PC, etc. */
void
m68k_push_dummy_frame (void)
{
register CORE_ADDR sp = read_register (SP_REGNUM);
register int regnum;
char raw_buffer[12];
sp = push_word (sp, read_register (PC_REGNUM));
sp = push_word (sp, read_register (FP_REGNUM));
write_register (FP_REGNUM, sp);
/* Always save the floating-point registers, whether they exist on
this target or not. */
for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--)
{
read_register_bytes (REGISTER_BYTE (regnum), raw_buffer, 12);
sp = push_bytes (sp, raw_buffer, 12);
}
for (regnum = FP_REGNUM - 1; regnum >= 0; regnum--)
{
sp = push_word (sp, read_register (regnum));
}
sp = push_word (sp, read_register (PS_REGNUM));
write_register (SP_REGNUM, sp);
}
/* Discard from the stack the innermost frame,
restoring all saved registers. */
void
m68k_pop_frame (void)
{
register struct frame_info *frame = get_current_frame ();
register CORE_ADDR fp;
register int regnum;
char raw_buffer[12];
fp = FRAME_FP (frame);
m68k_frame_init_saved_regs (frame);
for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--)
{
if (frame->saved_regs[regnum])
{
read_memory (frame->saved_regs[regnum], raw_buffer, 12);
write_register_bytes (REGISTER_BYTE (regnum), raw_buffer, 12);
}
}
for (regnum = FP_REGNUM - 1; regnum >= 0; regnum--)
{
if (frame->saved_regs[regnum])
{
write_register (regnum,
read_memory_integer (frame->saved_regs[regnum], 4));
}
}
if (frame->saved_regs[PS_REGNUM])
{
write_register (PS_REGNUM,
read_memory_integer (frame->saved_regs[PS_REGNUM], 4));
}
write_register (FP_REGNUM, read_memory_integer (fp, 4));
write_register (PC_REGNUM, read_memory_integer (fp + 4, 4));
write_register (SP_REGNUM, fp + 8);
flush_cached_frames ();
}
/* Given an ip value corresponding to the start of a function,
return the ip of the first instruction after the function
prologue. This is the generic m68k support. Machines which
require something different can override the SKIP_PROLOGUE
macro to point elsewhere.
Some instructions which typically may appear in a function
prologue include:
A link instruction, word form:
link.w %a6,&0 4e56 XXXX
A link instruction, long form:
link.l %fp,&F%1 480e XXXX XXXX
A movm instruction to preserve integer regs:
movm.l &M%1,(4,%sp) 48ef XXXX XXXX
A fmovm instruction to preserve float regs:
fmovm &FPM%1,(FPO%1,%sp) f237 XXXX XXXX XXXX XXXX
Some profiling setup code (FIXME, not recognized yet):
lea.l (.L3,%pc),%a1 43fb XXXX XXXX XXXX
bsr _mcount 61ff XXXX XXXX
*/
CORE_ADDR
m68k_skip_prologue (CORE_ADDR ip)
{
register CORE_ADDR limit;
struct symtab_and_line sal;
register int op;
/* Find out if there is a known limit for the extent of the prologue.
If so, ensure we don't go past it. If not, assume "infinity". */
sal = find_pc_line (ip, 0);
limit = (sal.end) ? sal.end : (CORE_ADDR) ~0;
while (ip < limit)
{
op = read_memory_integer (ip, 2);
op &= 0xFFFF;
if (op == P_LINKW_FP)
ip += 4; /* Skip link.w */
else if (op == P_PEA_FP)
ip += 2; /* Skip pea %fp */
else if (op == P_MOVL_SP_FP)
ip += 2; /* Skip move.l %sp, %fp */
else if (op == P_LINKL_FP)
ip += 6; /* Skip link.l */
else if (op == P_MOVML)
ip += 6; /* Skip movm.l */
else if (op == P_FMOVM)
ip += 10; /* Skip fmovm */
else
break; /* Found unknown code, bail out. */
}
return (ip);
}
/* Store the addresses of the saved registers of the frame described by
FRAME_INFO in its saved_regs field.
This includes special registers such as pc and fp saved in special
ways in the stack frame. sp is even more special:
the address we return for it IS the sp for the next frame. */
void
m68k_frame_init_saved_regs (struct frame_info *frame_info)
{
register int regnum;
register int regmask;
register CORE_ADDR next_addr;
register CORE_ADDR pc;
/* First possible address for a pc in a call dummy for this frame. */
CORE_ADDR possible_call_dummy_start =
(frame_info)->frame - 28 - FP_REGNUM * 4 - 4 - 8 * 12;
int nextinsn;
if (frame_info->saved_regs)
return;
frame_saved_regs_zalloc (frame_info);
memset (frame_info->saved_regs, 0, SIZEOF_FRAME_SAVED_REGS);
if ((frame_info)->pc >= possible_call_dummy_start
&& (frame_info)->pc <= (frame_info)->frame)
{
/* It is a call dummy. We could just stop now, since we know
what the call dummy saves and where. But this code proceeds
to parse the "prologue" which is part of the call dummy.
This is needlessly complex and confusing. FIXME. */
next_addr = (frame_info)->frame;
pc = possible_call_dummy_start;
}
else
{
pc = get_pc_function_start ((frame_info)->pc);
nextinsn = read_memory_integer (pc, 2);
if (P_PEA_FP == nextinsn
&& P_MOVL_SP_FP == read_memory_integer (pc + 2, 2))
{
/* pea %fp
move.l %sp, %fp */
next_addr = frame_info->frame;
pc += 4;
}
else if (P_LINKL_FP == nextinsn)
/* link.l %fp */
/* Find the address above the saved
regs using the amount of storage from the link instruction. */
{
next_addr = (frame_info)->frame + read_memory_integer (pc + 2, 4);
pc += 6;
}
else if (P_LINKW_FP == nextinsn)
/* link.w %fp */
/* Find the address above the saved
regs using the amount of storage from the link instruction. */
{
next_addr = (frame_info)->frame + read_memory_integer (pc + 2, 2);
pc += 4;
}
else
goto lose;
/* If have an addal #-n, sp next, adjust next_addr. */
if ((0177777 & read_memory_integer (pc, 2)) == 0157774)
next_addr += read_memory_integer (pc += 2, 4), pc += 4;
}
for (;;)
{
nextinsn = 0xffff & read_memory_integer (pc, 2);
regmask = read_memory_integer (pc + 2, 2);
/* fmovemx to -(sp) */
if (0xf227 == nextinsn && (regmask & 0xff00) == 0xe000)
{
/* Regmask's low bit is for register fp7, the first pushed */
for (regnum = FP0_REGNUM + 8; --regnum >= FP0_REGNUM; regmask >>= 1)
if (regmask & 1)
frame_info->saved_regs[regnum] = (next_addr -= 12);
pc += 4;
}
/* fmovemx to (fp + displacement) */
else if (0171056 == nextinsn && (regmask & 0xff00) == 0xf000)
{
register CORE_ADDR addr;
addr = (frame_info)->frame + read_memory_integer (pc + 4, 2);
/* Regmask's low bit is for register fp7, the first pushed */
for (regnum = FP0_REGNUM + 8; --regnum >= FP0_REGNUM; regmask >>= 1)
if (regmask & 1)
{
frame_info->saved_regs[regnum] = addr;
addr += 12;
}
pc += 6;
}
/* moveml to (sp) */
else if (0044327 == nextinsn)
{
/* Regmask's low bit is for register 0, the first written */
for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)
if (regmask & 1)
{
frame_info->saved_regs[regnum] = next_addr;
next_addr += 4;
}
pc += 4;
}
/* moveml to (fp + displacement) */
else if (0044356 == nextinsn)
{
register CORE_ADDR addr;
addr = (frame_info)->frame + read_memory_integer (pc + 4, 2);
/* Regmask's low bit is for register 0, the first written */
for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)
if (regmask & 1)
{
frame_info->saved_regs[regnum] = addr;
addr += 4;
}
pc += 6;
}
/* moveml to -(sp) */
else if (0044347 == nextinsn)
{
/* Regmask's low bit is for register 15, the first pushed */
for (regnum = 16; --regnum >= 0; regmask >>= 1)
if (regmask & 1)
frame_info->saved_regs[regnum] = (next_addr -= 4);
pc += 4;
}
/* movl r,-(sp) */
else if (0x2f00 == (0xfff0 & nextinsn))
{
regnum = 0xf & nextinsn;
frame_info->saved_regs[regnum] = (next_addr -= 4);
pc += 2;
}
/* fmovemx to index of sp */
else if (0xf236 == nextinsn && (regmask & 0xff00) == 0xf000)
{
/* Regmask's low bit is for register fp0, the first written */
for (regnum = FP0_REGNUM + 8; --regnum >= FP0_REGNUM; regmask >>= 1)
if (regmask & 1)
{
frame_info->saved_regs[regnum] = next_addr;
next_addr += 12;
}
pc += 10;
}
/* clrw -(sp); movw ccr,-(sp) */
else if (0x4267 == nextinsn && 0x42e7 == regmask)
{
frame_info->saved_regs[PS_REGNUM] = (next_addr -= 4);
pc += 4;
}
else
break;
}
lose:;
frame_info->saved_regs[SP_REGNUM] = (frame_info)->frame + 8;
frame_info->saved_regs[FP_REGNUM] = (frame_info)->frame;
frame_info->saved_regs[PC_REGNUM] = (frame_info)->frame + 4;
#ifdef SIG_SP_FP_OFFSET
/* Adjust saved SP_REGNUM for fake _sigtramp frames. */
if (frame_info->signal_handler_caller && frame_info->next)
frame_info->saved_regs[SP_REGNUM] =
frame_info->next->frame + SIG_SP_FP_OFFSET;
#endif
}
#ifdef USE_PROC_FS /* Target dependent support for /proc */
#include <sys/procfs.h>
/* Prototypes for supply_gregset etc. */
#include "gregset.h"
/* The /proc interface divides the target machine's register set up into
two different sets, the general register set (gregset) and the floating
point register set (fpregset). For each set, there is an ioctl to get
the current register set and another ioctl to set the current values.
The actual structure passed through the ioctl interface is, of course,
naturally machine dependent, and is different for each set of registers.
For the m68k for example, the general register set is typically defined
by:
typedef int gregset_t[18];
#define R_D0 0
...
#define R_PS 17
and the floating point set by:
typedef struct fpregset {
int f_pcr;
int f_psr;
int f_fpiaddr;
int f_fpregs[8][3]; (8 regs, 96 bits each)
} fpregset_t;
These routines provide the packing and unpacking of gregset_t and
fpregset_t formatted data.
*/
/* Atari SVR4 has R_SR but not R_PS */
#if !defined (R_PS) && defined (R_SR)
#define R_PS R_SR
#endif
/* Given a pointer to a general register set in /proc format (gregset_t *),
unpack the register contents and supply them as gdb's idea of the current
register values. */
void
supply_gregset (gregset_t *gregsetp)
{
register int regi;
register greg_t *regp = (greg_t *) gregsetp;
for (regi = 0; regi < R_PC; regi++)
{
supply_register (regi, (char *) (regp + regi));
}
supply_register (PS_REGNUM, (char *) (regp + R_PS));
supply_register (PC_REGNUM, (char *) (regp + R_PC));
}
void
fill_gregset (gregset_t *gregsetp, int regno)
{
register int regi;
register greg_t *regp = (greg_t *) gregsetp;
for (regi = 0; regi < R_PC; regi++)
{
if ((regno == -1) || (regno == regi))
{
*(regp + regi) = *(int *) &registers[REGISTER_BYTE (regi)];
}
}
if ((regno == -1) || (regno == PS_REGNUM))
{
*(regp + R_PS) = *(int *) &registers[REGISTER_BYTE (PS_REGNUM)];
}
if ((regno == -1) || (regno == PC_REGNUM))
{
*(regp + R_PC) = *(int *) &registers[REGISTER_BYTE (PC_REGNUM)];
}
}
#if defined (FP0_REGNUM)
/* Given a pointer to a floating point register set in /proc format
(fpregset_t *), unpack the register contents and supply them as gdb's
idea of the current floating point register values. */
void
supply_fpregset (fpregset_t *fpregsetp)
{
register int regi;
char *from;
for (regi = FP0_REGNUM; regi < E_FPC_REGNUM; regi++)
{
from = (char *) &(fpregsetp->f_fpregs[regi - FP0_REGNUM][0]);
supply_register (regi, from);
}
supply_register (E_FPC_REGNUM, (char *) &(fpregsetp->f_pcr));
supply_register (E_FPS_REGNUM, (char *) &(fpregsetp->f_psr));
supply_register (E_FPI_REGNUM, (char *) &(fpregsetp->f_fpiaddr));
}
/* Given a pointer to a floating point register set in /proc format
(fpregset_t *), update the register specified by REGNO from gdb's idea
of the current floating point register set. If REGNO is -1, update
them all. */
void
fill_fpregset (fpregset_t *fpregsetp, int regno)
{
int regi;
char *to;
char *from;
for (regi = FP0_REGNUM; regi < E_FPC_REGNUM; regi++)
{
if ((regno == -1) || (regno == regi))
{
from = (char *) &registers[REGISTER_BYTE (regi)];
to = (char *) &(fpregsetp->f_fpregs[regi - FP0_REGNUM][0]);
memcpy (to, from, REGISTER_RAW_SIZE (regi));
}
}
if ((regno == -1) || (regno == E_FPC_REGNUM))
{
fpregsetp->f_pcr = *(int *) &registers[REGISTER_BYTE (E_FPC_REGNUM)];
}
if ((regno == -1) || (regno == E_FPS_REGNUM))
{
fpregsetp->f_psr = *(int *) &registers[REGISTER_BYTE (E_FPS_REGNUM)];
}
if ((regno == -1) || (regno == E_FPI_REGNUM))
{
fpregsetp->f_fpiaddr = *(int *) &registers[REGISTER_BYTE (E_FPI_REGNUM)];
}
}
#endif /* defined (FP0_REGNUM) */
#endif /* USE_PROC_FS */
/* Figure out where the longjmp will land. Slurp the args out of the stack.
We expect the first arg to be a pointer to the jmp_buf structure from which
we extract the pc (JB_PC) that we will land at. The pc is copied into PC.
This routine returns true on success. */
/* NOTE: cagney/2000-11-08: For this function to be fully multi-arched
the macro's JB_PC and JB_ELEMENT_SIZE would need to be moved into
the ``struct gdbarch_tdep'' object and then set on a target ISA/ABI
dependant basis. */
int
m68k_get_longjmp_target (CORE_ADDR *pc)
{
#if defined (JB_PC) && defined (JB_ELEMENT_SIZE)
char *buf;
CORE_ADDR sp, jb_addr;
buf = alloca (TARGET_PTR_BIT / TARGET_CHAR_BIT);
sp = read_register (SP_REGNUM);
if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack */
buf, TARGET_PTR_BIT / TARGET_CHAR_BIT))
return 0;
jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf,
TARGET_PTR_BIT / TARGET_CHAR_BIT))
return 0;
*pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
return 1;
#else
internal_error (__FILE__, __LINE__,
"m68k_get_longjmp_target: not implemented");
return 0;
#endif
}
/* Immediately after a function call, return the saved pc before the frame
is setup. For sun3's, we check for the common case of being inside of a
system call, and if so, we know that Sun pushes the call # on the stack
prior to doing the trap. */
CORE_ADDR
m68k_saved_pc_after_call (struct frame_info *frame)
{
#ifdef SYSCALL_TRAP
int op;
op = read_memory_integer (frame->pc - SYSCALL_TRAP_OFFSET, 2);
if (op == SYSCALL_TRAP)
return read_memory_integer (read_register (SP_REGNUM) + 4, 4);
else
#endif /* SYSCALL_TRAP */
return read_memory_integer (read_register (SP_REGNUM), 4);
}
/* Function: m68k_gdbarch_init
Initializer function for the m68k gdbarch vector.
Called by gdbarch. Sets up the gdbarch vector(s) for this target. */
static struct gdbarch *
m68k_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
{
static LONGEST call_dummy_words[7] = { 0xf227e0ff, 0x48e7fffc, 0x426742e7,
0x4eb93232, 0x3232dffc, 0x69696969,
(0x4e404e71 | (BPT_VECTOR << 16))
};
struct gdbarch_tdep *tdep = NULL;
struct gdbarch *gdbarch;
/* find a candidate among the list of pre-declared architectures. */
arches = gdbarch_list_lookup_by_info (arches, &info);
if (arches != NULL)
return (arches->gdbarch);
#if 0
tdep = (struct gdbarch_tdep *) xmalloc (sizeof (struct gdbarch_tdep));
#endif
gdbarch = gdbarch_alloc (&info, 0);
set_gdbarch_long_double_format (gdbarch, &floatformat_m68881_ext);
set_gdbarch_long_double_bit (gdbarch, 96);
set_gdbarch_function_start_offset (gdbarch, 0);
set_gdbarch_skip_prologue (gdbarch, m68k_skip_prologue);
set_gdbarch_saved_pc_after_call (gdbarch, m68k_saved_pc_after_call);
set_gdbarch_breakpoint_from_pc (gdbarch, m68k_local_breakpoint_from_pc);
/* Stack grows down. */
set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
set_gdbarch_stack_align (gdbarch, m68k_stack_align);
set_gdbarch_believe_pcc_promotion (gdbarch, 1);
set_gdbarch_decr_pc_after_break (gdbarch, 2);
set_gdbarch_store_struct_return (gdbarch, m68k_store_struct_return);
set_gdbarch_deprecated_extract_return_value (gdbarch,
m68k_deprecated_extract_return_value);
set_gdbarch_store_return_value (gdbarch, m68k_store_return_value);
set_gdbarch_frame_chain (gdbarch, m68k_frame_chain);
set_gdbarch_frame_chain_valid (gdbarch, generic_func_frame_chain_valid);
set_gdbarch_frame_saved_pc (gdbarch, m68k_frame_saved_pc);
set_gdbarch_frame_init_saved_regs (gdbarch, m68k_frame_init_saved_regs);
set_gdbarch_frameless_function_invocation (gdbarch,
m68k_frameless_function_invocation);
/* OK to default this value to 'unknown'. */
set_gdbarch_frame_num_args (gdbarch, frame_num_args_unknown);
set_gdbarch_frame_args_skip (gdbarch, 8);
set_gdbarch_frame_args_address (gdbarch, default_frame_address);
set_gdbarch_frame_locals_address (gdbarch, default_frame_address);
set_gdbarch_register_raw_size (gdbarch, m68k_register_raw_size);
set_gdbarch_register_virtual_size (gdbarch, m68k_register_virtual_size);
set_gdbarch_max_register_raw_size (gdbarch, 12);
set_gdbarch_max_register_virtual_size (gdbarch, 12);
set_gdbarch_register_virtual_type (gdbarch, m68k_register_virtual_type);
set_gdbarch_register_name (gdbarch, m68k_register_name);
set_gdbarch_register_size (gdbarch, 4);
set_gdbarch_register_byte (gdbarch, m68k_register_byte);
set_gdbarch_num_regs (gdbarch, 29);
set_gdbarch_register_bytes_ok (gdbarch, m68k_register_bytes_ok);
set_gdbarch_register_bytes (gdbarch, (16 * 4 + 8 + 8 * 12 + 3 * 4));
set_gdbarch_sp_regnum (gdbarch, E_SP_REGNUM);
set_gdbarch_fp_regnum (gdbarch, E_FP_REGNUM);
set_gdbarch_pc_regnum (gdbarch, E_PC_REGNUM);
set_gdbarch_ps_regnum (gdbarch, E_PS_REGNUM);
set_gdbarch_fp0_regnum (gdbarch, E_FP0_REGNUM);
set_gdbarch_use_generic_dummy_frames (gdbarch, 0);
set_gdbarch_call_dummy_location (gdbarch, ON_STACK);
set_gdbarch_call_dummy_breakpoint_offset_p (gdbarch, 1);
set_gdbarch_call_dummy_breakpoint_offset (gdbarch, 24);
set_gdbarch_pc_in_call_dummy (gdbarch, pc_in_call_dummy_on_stack);
set_gdbarch_call_dummy_p (gdbarch, 1);
set_gdbarch_call_dummy_stack_adjust_p (gdbarch, 0);
set_gdbarch_call_dummy_length (gdbarch, 28);
set_gdbarch_call_dummy_start_offset (gdbarch, 12);
set_gdbarch_call_dummy_words (gdbarch, call_dummy_words);
set_gdbarch_sizeof_call_dummy_words (gdbarch, sizeof (call_dummy_words));
set_gdbarch_call_dummy_stack_adjust_p (gdbarch, 0);
set_gdbarch_fix_call_dummy (gdbarch, m68k_fix_call_dummy);
set_gdbarch_push_dummy_frame (gdbarch, m68k_push_dummy_frame);
set_gdbarch_pop_frame (gdbarch, m68k_pop_frame);
return gdbarch;
}
static void
m68k_dump_tdep (struct gdbarch *current_gdbarch, struct ui_file *file)
{
}
void
_initialize_m68k_tdep (void)
{
gdbarch_register (bfd_arch_m68k, m68k_gdbarch_init, m68k_dump_tdep);
tm_print_insn = print_insn_m68k;
}