/*-
 * Mach Operating System
 * Copyright (c) 1991,1990 Carnegie Mellon University
 * All Rights Reserved.
 *
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */

#ifndef _MACHINE_DB_MACHDEP_H_
#define _MACHINE_DB_MACHDEP_H_

#include <machine/frame.h>
#include <machine/trap.h>

typedef vm_offset_t     db_addr_t;      /* address - unsigned */
typedef int             db_expr_t;      /* expression - signed */

#define PC_REGS()       ((db_addr_t)(kdb_frame->tf_eflags & PSL_VM ?    \
                            (kdb_frame->tf_eip & 0xffff) +              \
                            ((kdb_frame->tf_cs & 0xffff) << 4) :        \
                            kdb_frame->tf_eip))

#define BKPT_INST       0xcc            /* breakpoint instruction */
#define BKPT_SIZE       (1)             /* size of breakpoint inst */
#define BKPT_SET(inst)  (BKPT_INST)

#define BKPT_SKIP                               \
do {                                            \
        kdb_frame->tf_eip += 1;                 \
        kdb_thrctx->pcb_eip += 1;               \
} while(0)

#define FIXUP_PC_AFTER_BREAK                    \
do {                                            \
        kdb_frame->tf_eip -= 1;                 \
        kdb_thrctx->pcb_eip -= 1;               \
} while(0);

#define db_clear_single_step    kdb_cpu_clear_singlestep
#define db_set_single_step      kdb_cpu_set_singlestep

/*
 * The debug exception type is copied from %dr6 to 'code' and used to
 * disambiguate single step traps.  Watchpoints have no special support.
 * Our hardware breakpoints are not well integrated with ddb and are too
 * different from watchpoints.  ddb treats them as unknown traps with
 * unknown addresses and doesn't turn them off while it is running.
 */
#define IS_BREAKPOINT_TRAP(type, code)  ((type) == T_BPTFLT)
#define IS_SSTEP_TRAP(type, code)                                       \
        ((type) == T_TRCTRAP && (code) & DBREG_DR6_BS)
#define IS_WATCHPOINT_TRAP(type, code)  0

#define I_CALL          0xe8
#define I_CALLI         0xff
#define I_RET           0xc3
#define I_IRET          0xcf

#define inst_trap_return(ins)   (((ins)&0xff) == I_IRET)
#define inst_return(ins)        (((ins)&0xff) == I_RET)
#define inst_call(ins)          (((ins)&0xff) == I_CALL || \
                                 (((ins)&0xff) == I_CALLI && \
                                  ((ins)&0x3800) == 0x1000))
#define inst_load(ins)          0
#define inst_store(ins)         0

int     db_segsize(struct trapframe *tfp);

#endif /* !_MACHINE_DB_MACHDEP_H_ */