373 lines
13 KiB
C
373 lines
13 KiB
C
/* Parameters for execution on a 68000 series machine.
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Copyright 1986, 1987, 1989, 1990, 1992, 1993, 1994, 1995, 1996, 1998,
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1999, 2000 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 "regcache.h"
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/* Generic 68000 stuff, to be included by other tm-*.h files. */
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#define IEEE_FLOAT (1)
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/* Define the bit, byte, and word ordering of the machine. */
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#define TARGET_BYTE_ORDER BFD_ENDIAN_BIG
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#define TARGET_LONG_DOUBLE_FORMAT &floatformat_m68881_ext
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#define TARGET_LONG_DOUBLE_BIT 96
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/* Offset from address of function to start of its code.
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Zero on most machines. */
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#define FUNCTION_START_OFFSET 0
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/* Advance PC across any function entry prologue instructions
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to reach some "real" code. */
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#if !defined(SKIP_PROLOGUE)
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#define SKIP_PROLOGUE(ip) (m68k_skip_prologue (ip))
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#endif
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extern CORE_ADDR m68k_skip_prologue (CORE_ADDR ip);
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/* Immediately after a function call, return the saved pc.
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Can't always go through the frames for this because on some machines
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the new frame is not set up until the new function executes
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some instructions. */
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struct frame_info;
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struct frame_saved_regs;
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extern CORE_ADDR m68k_saved_pc_after_call (struct frame_info *);
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extern void m68k_find_saved_regs (struct frame_info *,
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struct frame_saved_regs *);
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#define SAVED_PC_AFTER_CALL(frame) \
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m68k_saved_pc_after_call(frame)
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/* Stack grows downward. */
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#define INNER_THAN(lhs,rhs) ((lhs) < (rhs))
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/* Stack must be kept short aligned when doing function calls. */
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#define STACK_ALIGN(ADDR) (((ADDR) + 1) & ~1)
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/* Sequence of bytes for breakpoint instruction.
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This is a TRAP instruction. The last 4 bits (0xf below) is the
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vector. Systems which don't use 0xf should define BPT_VECTOR
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themselves before including this file. */
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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 (BREAKPOINT)
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#define BREAKPOINT {0x4e, (0x40 | BPT_VECTOR)}
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#endif
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/* We default to vector 1 for the "remote" target, but allow targets
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to override. */
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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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#if !defined (REMOTE_BREAKPOINT)
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#define REMOTE_BREAKPOINT {0x4e, (0x40 | REMOTE_BPT_VECTOR)}
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#endif
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/* If your kernel resets the pc after the trap happens you may need to
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define this before including this file. */
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#if !defined (DECR_PC_AFTER_BREAK)
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#define DECR_PC_AFTER_BREAK 2
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#endif
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/* Say how long (ordinary) registers are. This is a piece of bogosity
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used in push_word and a few other places; REGISTER_RAW_SIZE is the
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real way to know how big a register is. */
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#define REGISTER_SIZE 4
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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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#ifndef NUM_REGS
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#define NUM_REGS 29
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#endif
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#define NUM_FREGS (NUM_REGS-24)
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#ifndef REGISTER_BYTES_OK
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#define REGISTER_BYTES_OK(b) \
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((b) == REGISTER_BYTES_FP \
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|| (b) == REGISTER_BYTES_NOFP)
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#endif
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#ifndef REGISTER_BYTES
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#define REGISTER_BYTES (16*4 + 8 + 8*12 + 3*4)
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#endif
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/* Index within `registers' of the first byte of the space for
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register N. */
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#define REGISTER_BYTE(N) \
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((N) >= FPC_REGNUM ? (((N) - FPC_REGNUM) * 4) + 168 \
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: (N) >= FP0_REGNUM ? (((N) - FP0_REGNUM) * 12) + 72 \
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: (N) * 4)
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/* Number of bytes of storage in the actual machine representation
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for register N. 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 N < FP0_REGNUM */
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#define REGISTER_RAW_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 12 : 4)
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/* Number of bytes of storage in the program's representation
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for register N. 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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#define REGISTER_VIRTUAL_SIZE(N) (((unsigned)(N) - FP0_REGNUM) < 8 ? 12 : 4)
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/* Largest value REGISTER_RAW_SIZE can have. */
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#define MAX_REGISTER_RAW_SIZE 12
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/* Largest value REGISTER_VIRTUAL_SIZE can have. */
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#define MAX_REGISTER_VIRTUAL_SIZE 12
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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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#define REGISTER_VIRTUAL_TYPE(N) \
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((unsigned) (N) >= FPC_REGNUM ? lookup_pointer_type (builtin_type_void) : \
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(unsigned) (N) >= FP0_REGNUM ? builtin_type_long_double : \
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(unsigned) (N) >= A0_REGNUM ? lookup_pointer_type (builtin_type_void) : \
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builtin_type_int)
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/* Initializer for an array of names of registers.
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Entries beyond the first NUM_REGS are ignored. */
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#define 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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/* 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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#define D0_REGNUM 0
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#define A0_REGNUM 8
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#define A1_REGNUM 9
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#define FP_REGNUM 14 /* Contains address of executing stack frame */
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#define SP_REGNUM 15 /* Contains address of top of stack */
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#define PS_REGNUM 16 /* Contains processor status */
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#define PC_REGNUM 17 /* Contains program counter */
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#define FP0_REGNUM 18 /* Floating point register 0 */
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#define FPC_REGNUM 26 /* 68881 control register */
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#define FPS_REGNUM 27 /* 68881 status register */
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#define FPI_REGNUM 28 /* 68881 iaddr register */
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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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#define STORE_STRUCT_RETURN(ADDR, SP) \
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{ write_register (A1_REGNUM, (ADDR)); }
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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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#if !defined (EXTRACT_RETURN_VALUE)
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#define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
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memcpy ((VALBUF), \
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(char *)(REGBUF) + \
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(TYPE_LENGTH(TYPE) >= 4 ? 0 : 4 - TYPE_LENGTH(TYPE)), \
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TYPE_LENGTH(TYPE))
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#endif
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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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#if !defined (STORE_RETURN_VALUE)
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#define STORE_RETURN_VALUE(TYPE,VALBUF) \
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write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
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#endif
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/* Extract from an array REGBUF containing the (raw) register state
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the address in which a function should return its structure value,
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as a CORE_ADDR (or an expression that can be used as one). */
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#define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(CORE_ADDR *)(REGBUF))
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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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#define FRAME_CHAIN(thisframe) \
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(thisframe->signal_handler_caller \
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? thisframe->frame \
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: (!inside_entry_file ((thisframe)->pc) \
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? read_memory_integer ((thisframe)->frame, 4) \
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: 0))
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/* Define other aspects of the stack frame. */
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/* A macro 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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#define FRAMELESS_FUNCTION_INVOCATION(FI) \
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(((FI)->signal_handler_caller) ? 0 : frameless_look_for_prologue(FI))
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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 FRAME_SAVED_PC(FRAME) \
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(((FRAME)->signal_handler_caller \
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? ((FRAME)->next \
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? read_memory_integer ((FRAME)->next->frame + SIG_PC_FP_OFFSET, 4) \
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: 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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: read_memory_integer ((FRAME)->frame + 4, 4)) \
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)
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#define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
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#define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
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/* Set VAL to the number of args passed to frame described by FI.
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Can set VAL to -1, meaning no way to tell. */
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/* We can't tell how many args there are
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now that the C compiler delays popping them. */
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#if !defined (FRAME_NUM_ARGS)
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#define FRAME_NUM_ARGS(fi) (-1)
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#endif
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/* Return number of bytes at start of arglist that are not really args. */
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#define FRAME_ARGS_SKIP 8
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/* Put here the code to store, into a struct frame_saved_regs,
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the addresses of the saved registers of frame described by FRAME_INFO.
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This includes special registers such as pc and fp saved in special
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ways in the stack frame. sp is even more special:
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the address we return for it IS the sp for the next frame. */
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#if !defined (FRAME_FIND_SAVED_REGS)
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#define FRAME_FIND_SAVED_REGS(fi,fsr) m68k_find_saved_regs ((fi), &(fsr))
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#endif /* no FIND_FRAME_SAVED_REGS. */
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/* Things needed for making the inferior call functions. */
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/* The CALL_DUMMY macro is the sequence of instructions, as disassembled
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by gdb itself:
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These instructions exist only so that m68k_find_saved_regs can parse
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them as a "prologue"; they are never executed.
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fmovemx fp0-fp7,sp@- 0xf227 0xe0ff
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moveml d0-a5,sp@- 0x48e7 0xfffc
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clrw sp@- 0x4267
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movew ccr,sp@- 0x42e7
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The arguments are pushed at this point by GDB; no code is needed in
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the dummy for this. The CALL_DUMMY_START_OFFSET gives the position
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of the following jsr instruction. That is where we start
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executing.
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jsr @#0x32323232 0x4eb9 0x3232 0x3232
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addal #0x69696969,sp 0xdffc 0x6969 0x6969
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trap #<your BPT_VECTOR number here> 0x4e4?
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nop 0x4e71
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Note this is CALL_DUMMY_LENGTH bytes (28 for the above example).
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The dummy frame always saves the floating-point registers, whether they
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actually exist on this target or not. */
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/* FIXME: Wrong to hardwire this as BPT_VECTOR when sometimes it
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should be REMOTE_BPT_VECTOR. Best way to fix it would be to define
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CALL_DUMMY_BREAKPOINT_OFFSET. */
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#define CALL_DUMMY {0xf227e0ff, 0x48e7fffc, 0x426742e7, 0x4eb93232, 0x3232dffc, 0x69696969, (0x4e404e71 | (BPT_VECTOR << 16))}
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#define CALL_DUMMY_LENGTH 28 /* Size of CALL_DUMMY */
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#define CALL_DUMMY_START_OFFSET 12 /* Offset to jsr instruction */
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#define CALL_DUMMY_BREAKPOINT_OFFSET (CALL_DUMMY_START_OFFSET + 12)
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/* Insert the specified number of args and function address
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into a call sequence of the above form stored at DUMMYNAME.
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We use the BFD routines to store a big-endian value of known size. */
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#define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p) \
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{ bfd_putb32 (fun, (unsigned char *) dummyname + CALL_DUMMY_START_OFFSET + 2); \
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bfd_putb32 (nargs*4, (unsigned char *) dummyname + CALL_DUMMY_START_OFFSET + 8); }
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/* Push an empty stack frame, to record the current PC, etc. */
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#define PUSH_DUMMY_FRAME { m68k_push_dummy_frame (); }
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extern void m68k_push_dummy_frame (void);
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extern void m68k_pop_frame (void);
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/* Discard from the stack the innermost frame, restoring all registers. */
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#define POP_FRAME { m68k_pop_frame (); }
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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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#define TARGET_M68K
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/* Figure out where the longjmp will land. Slurp the args out of the stack.
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We expect the first arg to be a pointer to the jmp_buf structure from which
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we extract the pc (JB_PC) that we will land at. The pc is copied into ADDR.
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This routine returns true on success */
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extern int m68k_get_longjmp_target (CORE_ADDR *);
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