xref: /openbsd-src/gnu/usr.bin/binutils/gdb/config/mips/tm-mips.h (revision 63addd46c1e40ca0f49488ddcdc4ab598023b0c1)

/* Definitions to make GDB run on a mips box under 4.3bsd.

   Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996,
   1997, 1998, 1999, 2000, 2002, 2003 Free Software Foundation, Inc.

   Contributed by Per Bothner (bothner@cs.wisc.edu) at U.Wisconsin
   and by Alessandro Forin (af@cs.cmu.edu) at CMU..

   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.  */

#ifndef TM_MIPS_H
#define TM_MIPS_H 1

#include "regcache.h"

struct frame_info;
struct symbol;
struct type;
struct value;

#include <bfd.h>
#include "coff/sym.h"		/* Needed for PDR below.  */
#include "coff/symconst.h"

/* Return non-zero if PC points to an instruction which will cause a step
   to execute both the instruction at PC and an instruction at PC+4.  */
extern int mips_step_skips_delay (CORE_ADDR);
#define STEP_SKIPS_DELAY_P (1)
#define STEP_SKIPS_DELAY(pc) (mips_step_skips_delay (pc))

/* 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.  */

#define ZERO_REGNUM 0		/* read-only register, always 0 */
#define V0_REGNUM 2		/* Function integer return value */
#define A0_REGNUM 4		/* Loc of first arg during a subr call */
#define T9_REGNUM 25		/* Contains address of callee in PIC */
#define RA_REGNUM 31		/* Contains return address value */
#define PS_REGNUM 32		/* Contains processor status */
#define	UNUSED_REGNUM 73	/* Never used, FIXME */
#define	FIRST_EMBED_REGNUM 74	/* First CP0 register for embedded use */
#define	PRID_REGNUM 89		/* Processor ID */
#define	LAST_EMBED_REGNUM 89	/* Last one */

/* Special symbol found in blocks associated with routines.  We can hang
   mips_extra_func_info_t's off of this.  */

#define MIPS_EFI_SYMBOL_NAME "__GDB_EFI_INFO__"
extern void ecoff_relocate_efi (struct symbol *, CORE_ADDR);

/* Specific information about a procedure.
   This overlays the MIPS's PDR records,
   mipsread.c (ab)uses this to save memory */

typedef struct mips_extra_func_info
  {
    long numargs;		/* number of args to procedure (was iopt) */
    bfd_vma high_addr;		/* upper address bound */
    long frame_adjust;		/* offset of FP from SP (used on MIPS16) */
    PDR pdr;			/* Procedure descriptor record */
  }
 *mips_extra_func_info_t;

/* It takes two values to specify a frame on the MIPS.

   In fact, the *PC* is the primary value that sets up a frame.  The
   PC is looked up to see what function it's in; symbol information
   from that function tells us which register is the frame pointer
   base, and what offset from there is the "virtual frame pointer".
   (This is usually an offset from SP.)  On most non-MIPS machines,
   the primary value is the SP, and the PC, if needed, disambiguates
   multiple functions with the same SP.  But on the MIPS we can't do
   that since the PC is not stored in the same part of the frame every
   time.  This does not seem to be a very clever way to set up frames,
   but there is nothing we can do about that.  */

#define SETUP_ARBITRARY_FRAME(argc, argv) setup_arbitrary_frame (argc, argv)
extern struct frame_info *setup_arbitrary_frame (int, CORE_ADDR *);

/* Functions for dealing with MIPS16 call and return stubs.  */
#define DEPRECATED_IGNORE_HELPER_CALL(pc)			mips_ignore_helper (pc)
extern int mips_ignore_helper (CORE_ADDR pc);

/* Definitions and declarations used by mips-tdep.c and remote-mips.c  */
#define MIPS_INSTLEN 4		/* Length of an instruction */
#define MIPS16_INSTLEN 2	/* Length of an instruction on MIPS16 */
#define MIPS_NUMREGS 32		/* Number of integer or float registers */
typedef unsigned long t_inst;	/* Integer big enough to hold an instruction */

#endif /* TM_MIPS_H */

/* Single step based on where the current instruction will take us.  */
extern void mips_software_single_step (enum target_signal, int);