1082 lines
32 KiB
C
1082 lines
32 KiB
C
/* Target dependent code for the Motorola 68000 series.
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Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1999, 2000, 2001
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Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include "defs.h"
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#include "frame.h"
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#include "symtab.h"
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#include "gdbcore.h"
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#include "value.h"
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#include "gdb_string.h"
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#include "inferior.h"
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#include "regcache.h"
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#include "arch-utils.h"
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#define P_LINKL_FP 0x480e
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#define P_LINKW_FP 0x4e56
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#define P_PEA_FP 0x4856
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#define P_MOVL_SP_FP 0x2c4f
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#define P_MOVL 0x207c
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#define P_JSR 0x4eb9
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#define P_BSR 0x61ff
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#define P_LEAL 0x43fb
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#define P_MOVML 0x48ef
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#define P_FMOVM 0xf237
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#define P_TRAP 0x4e40
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/* Register numbers of various important registers.
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Note that some of these values are "real" register numbers,
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and correspond to the general registers of the machine,
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and some are "phony" register numbers which are too large
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to be actual register numbers as far as the user is concerned
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but do serve to get the desired values when passed to read_register. */
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/* Note: Since they are used in files other than this (monitor files),
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D0_REGNUM and A0_REGNUM are currently defined in tm-m68k.h. */
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enum
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{
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E_A1_REGNUM = 9,
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E_FP_REGNUM = 14, /* Contains address of executing stack frame */
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E_SP_REGNUM = 15, /* Contains address of top of stack */
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E_PS_REGNUM = 16, /* Contains processor status */
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E_PC_REGNUM = 17, /* Contains program counter */
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E_FP0_REGNUM = 18, /* Floating point register 0 */
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E_FPC_REGNUM = 26, /* 68881 control register */
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E_FPS_REGNUM = 27, /* 68881 status register */
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E_FPI_REGNUM = 28
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};
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#define REGISTER_BYTES_FP (16*4 + 8 + 8*12 + 3*4)
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#define REGISTER_BYTES_NOFP (16*4 + 8)
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#define NUM_FREGS (NUM_REGS-24)
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/* Offset from SP to first arg on stack at first instruction of a function */
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#define SP_ARG0 (1 * 4)
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/* This was determined by experimentation on hp300 BSD 4.3. Perhaps
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it corresponds to some offset in /usr/include/sys/user.h or
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something like that. Using some system include file would
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have the advantage of probably being more robust in the face
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of OS upgrades, but the disadvantage of being wrong for
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cross-debugging. */
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#define SIG_PC_FP_OFFSET 530
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#define TARGET_M68K
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#if !defined (BPT_VECTOR)
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#define BPT_VECTOR 0xf
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#endif
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#if !defined (REMOTE_BPT_VECTOR)
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#define REMOTE_BPT_VECTOR 1
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#endif
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void m68k_frame_init_saved_regs (struct frame_info *frame_info);
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/* gdbarch_breakpoint_from_pc is set to m68k_local_breakpoint_from_pc
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so m68k_remote_breakpoint_from_pc is currently not used. */
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const static unsigned char *
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m68k_remote_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
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{
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static unsigned char break_insn[] = {0x4e, (0x40 | REMOTE_BPT_VECTOR)};
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*lenptr = sizeof (break_insn);
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return break_insn;
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}
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const static unsigned char *
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m68k_local_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
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{
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static unsigned char break_insn[] = {0x4e, (0x40 | BPT_VECTOR)};
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*lenptr = sizeof (break_insn);
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return break_insn;
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}
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static int
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m68k_register_bytes_ok (long numbytes)
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{
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return ((numbytes == REGISTER_BYTES_FP)
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|| (numbytes == REGISTER_BYTES_NOFP));
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}
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/* Number of bytes of storage in the actual machine representation
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for register regnum. On the 68000, all regs are 4 bytes
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except the floating point regs which are 12 bytes. */
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/* Note that the unsigned cast here forces the result of the
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subtraction to very high positive values if regnum < FP0_REGNUM */
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static int
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m68k_register_raw_size (int regnum)
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{
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return (((unsigned) (regnum) - FP0_REGNUM) < 8 ? 12 : 4);
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}
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/* Number of bytes of storage in the program's representation
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for register regnum. On the 68000, all regs are 4 bytes
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except the floating point regs which are 12-byte long doubles. */
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static int
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m68k_register_virtual_size (int regnum)
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{
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return (((unsigned) (regnum) - FP0_REGNUM) < 8 ? 12 : 4);
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}
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/* Return the GDB type object for the "standard" data type of data
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in register N. This should be int for D0-D7, long double for FP0-FP7,
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and void pointer for all others (A0-A7, PC, SR, FPCONTROL etc).
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Note, for registers which contain addresses return pointer to void,
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not pointer to char, because we don't want to attempt to print
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the string after printing the address. */
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static struct type *
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m68k_register_virtual_type (int regnum)
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{
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if ((unsigned) regnum >= E_FPC_REGNUM)
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return lookup_pointer_type (builtin_type_void);
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else if ((unsigned) regnum >= FP0_REGNUM)
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return builtin_type_long_double;
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else if ((unsigned) regnum >= A0_REGNUM)
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return lookup_pointer_type (builtin_type_void);
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else
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return builtin_type_int;
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}
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/* Function: m68k_register_name
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Returns the name of the standard m68k register regnum. */
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static const char *
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m68k_register_name (int regnum)
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{
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static char *register_names[] = {
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"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7",
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"a0", "a1", "a2", "a3", "a4", "a5", "fp", "sp",
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"ps", "pc",
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"fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7",
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"fpcontrol", "fpstatus", "fpiaddr", "fpcode", "fpflags"
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};
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if (regnum < 0 ||
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regnum >= sizeof (register_names) / sizeof (register_names[0]))
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internal_error (__FILE__, __LINE__,
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"m68k_register_name: illegal register number %d", regnum);
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else
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return register_names[regnum];
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}
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/* Stack must be kept short aligned when doing function calls. */
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static CORE_ADDR
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m68k_stack_align (CORE_ADDR addr)
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{
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return ((addr + 1) & ~1);
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}
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/* Index within `registers' of the first byte of the space for
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register regnum. */
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static int
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m68k_register_byte (int regnum)
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{
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if (regnum >= E_FPC_REGNUM)
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return (((regnum - E_FPC_REGNUM) * 4) + 168);
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else if (regnum >= FP0_REGNUM)
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return (((regnum - FP0_REGNUM) * 12) + 72);
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else
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return (regnum * 4);
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}
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/* Store the address of the place in which to copy the structure the
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subroutine will return. This is called from call_function. */
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static void
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m68k_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
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{
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write_register (E_A1_REGNUM, addr);
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}
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/* Extract from an array regbuf containing the (raw) register state
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a function return value of type type, and copy that, in virtual format,
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into valbuf. This is assuming that floating point values are returned
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as doubles in d0/d1. */
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static void
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m68k_deprecated_extract_return_value (struct type *type, char *regbuf,
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char *valbuf)
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{
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int offset = 0;
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int typeLength = TYPE_LENGTH (type);
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if (typeLength < 4)
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offset = 4 - typeLength;
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memcpy (valbuf, regbuf + offset, typeLength);
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}
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static CORE_ADDR
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m68k_deprecated_extract_struct_value_address (char *regbuf)
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{
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return (*(CORE_ADDR *) (regbuf));
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}
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/* Write into appropriate registers a function return value
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of type TYPE, given in virtual format. Assumes floats are passed
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in d0/d1. */
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static void
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m68k_store_return_value (struct type *type, char *valbuf)
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{
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write_register_bytes (0, valbuf, TYPE_LENGTH (type));
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}
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/* Describe the pointer in each stack frame to the previous stack frame
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(its caller). */
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/* FRAME_CHAIN takes a frame's nominal address and produces the frame's
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chain-pointer.
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In the case of the 68000, the frame's nominal address
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is the address of a 4-byte word containing the calling frame's address. */
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/* If we are chaining from sigtramp, then manufacture a sigtramp frame
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(which isn't really on the stack. I'm not sure this is right for anything
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but BSD4.3 on an hp300. */
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static CORE_ADDR
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m68k_frame_chain (struct frame_info *thisframe)
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{
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if (thisframe->signal_handler_caller)
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return thisframe->frame;
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else if (!inside_entry_file ((thisframe)->pc))
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return read_memory_integer ((thisframe)->frame, 4);
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else
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return 0;
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}
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/* A function that tells us whether the function invocation represented
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by fi does not have a frame on the stack associated with it. If it
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does not, FRAMELESS is set to 1, else 0. */
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static int
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m68k_frameless_function_invocation (struct frame_info *fi)
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{
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if (fi->signal_handler_caller)
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return 0;
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else
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return frameless_look_for_prologue (fi);
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}
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static CORE_ADDR
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m68k_frame_saved_pc (struct frame_info *frame)
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{
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if (frame->signal_handler_caller)
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{
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if (frame->next)
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return read_memory_integer (frame->next->frame + SIG_PC_FP_OFFSET, 4);
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else
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return read_memory_integer (read_register (SP_REGNUM)
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+ SIG_PC_FP_OFFSET - 8, 4);
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}
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else
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return read_memory_integer (frame->frame + 4, 4);
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}
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/* The only reason this is here is the tm-altos.h reference below. It
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was moved back here from tm-m68k.h. FIXME? */
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extern CORE_ADDR
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altos_skip_prologue (CORE_ADDR pc)
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{
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register int op = read_memory_integer (pc, 2);
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if (op == P_LINKW_FP)
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pc += 4; /* Skip link #word */
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else if (op == P_LINKL_FP)
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pc += 6; /* Skip link #long */
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/* Not sure why branches are here. */
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/* From tm-altos.h */
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else if (op == 0060000)
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pc += 4; /* Skip bra #word */
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else if (op == 00600377)
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pc += 6; /* skip bra #long */
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else if ((op & 0177400) == 0060000)
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pc += 2; /* skip bra #char */
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return pc;
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}
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int
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delta68_in_sigtramp (CORE_ADDR pc, char *name)
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{
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if (name != NULL)
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return strcmp (name, "_sigcode") == 0;
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else
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return 0;
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}
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CORE_ADDR
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delta68_frame_args_address (struct frame_info *frame_info)
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{
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/* we assume here that the only frameless functions are the system calls
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or other functions who do not put anything on the stack. */
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if (frame_info->signal_handler_caller)
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return frame_info->frame + 12;
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else if (frameless_look_for_prologue (frame_info))
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{
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/* Check for an interrupted system call */
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if (frame_info->next && frame_info->next->signal_handler_caller)
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return frame_info->next->frame + 16;
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else
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return frame_info->frame + 4;
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}
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else
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return frame_info->frame;
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}
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CORE_ADDR
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delta68_frame_saved_pc (struct frame_info *frame_info)
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{
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return read_memory_integer (delta68_frame_args_address (frame_info) + 4, 4);
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}
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/* Return number of args passed to a frame.
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Can return -1, meaning no way to tell. */
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int
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isi_frame_num_args (struct frame_info *fi)
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{
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int val;
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CORE_ADDR pc = FRAME_SAVED_PC (fi);
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int insn = 0177777 & read_memory_integer (pc, 2);
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val = 0;
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if (insn == 0047757 || insn == 0157374) /* lea W(sp),sp or addaw #W,sp */
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val = read_memory_integer (pc + 2, 2);
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else if ((insn & 0170777) == 0050217 /* addql #N, sp */
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|| (insn & 0170777) == 0050117) /* addqw */
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{
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val = (insn >> 9) & 7;
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if (val == 0)
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val = 8;
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}
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else if (insn == 0157774) /* addal #WW, sp */
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val = read_memory_integer (pc + 2, 4);
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val >>= 2;
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return val;
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}
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||
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int
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delta68_frame_num_args (struct frame_info *fi)
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{
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int val;
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CORE_ADDR pc = FRAME_SAVED_PC (fi);
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int insn = 0177777 & read_memory_integer (pc, 2);
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val = 0;
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if (insn == 0047757 || insn == 0157374) /* lea W(sp),sp or addaw #W,sp */
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val = read_memory_integer (pc + 2, 2);
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else if ((insn & 0170777) == 0050217 /* addql #N, sp */
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|| (insn & 0170777) == 0050117) /* addqw */
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{
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val = (insn >> 9) & 7;
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if (val == 0)
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val = 8;
|
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}
|
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else if (insn == 0157774) /* addal #WW, sp */
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||
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 *) ®isters[REGISTER_BYTE (regi)];
|
||
}
|
||
}
|
||
if ((regno == -1) || (regno == PS_REGNUM))
|
||
{
|
||
*(regp + R_PS) = *(int *) ®isters[REGISTER_BYTE (PS_REGNUM)];
|
||
}
|
||
if ((regno == -1) || (regno == PC_REGNUM))
|
||
{
|
||
*(regp + R_PC) = *(int *) ®isters[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 *) ®isters[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 *) ®isters[REGISTER_BYTE (E_FPC_REGNUM)];
|
||
}
|
||
if ((regno == -1) || (regno == E_FPS_REGNUM))
|
||
{
|
||
fpregsetp->f_psr = *(int *) ®isters[REGISTER_BYTE (E_FPS_REGNUM)];
|
||
}
|
||
if ((regno == -1) || (regno == E_FPI_REGNUM))
|
||
{
|
||
fpregsetp->f_fpiaddr = *(int *) ®isters[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;
|
||
}
|