gdb/config/ns32k/tm-merlin.h

   1 /* Definitions to target GDB to a merlin under utek 2.1
   2    Copyright 1986, 1987, 1989, 1991, 1993, 1994, 1998, 1999, 2000
   3    Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #define TARGET_BYTE_ORDER LITTLE_ENDIAN
  23
  24 /* Offset from address of function to start of its code.
  25    Zero on most machines.  */
  26
  27 #define FUNCTION_START_OFFSET 0
  28
  29 /* Advance PC across any function entry prologue instructions
  30    to reach some "real" code.  */
  31
  32 extern CORE_ADDR merlin_skip_prologue (CORE_ADDR);
  33 #define SKIP_PROLOGUE(pc) (merlin_skip_prologue (pc))
  34
  35 /* Immediately after a function call, return the saved pc.
  36    Can't always go through the frames for this because on some machines
  37    the new frame is not set up until the new function executes
  38    some instructions.  */
  39
  40 #define SAVED_PC_AFTER_CALL(frame) \
  41         read_memory_integer (read_register (SP_REGNUM), 4)
  42
  43 /* Address of end of stack space.  */
  44
  45 #define STACK_END_ADDR (0x800000)
  46
  47 /* Stack grows downward.  */
  48
  49 #define INNER_THAN(lhs,rhs) ((lhs) < (rhs))
  50
  51 /* Sequence of bytes for breakpoint instruction.  */
  52
  53 #define BREAKPOINT {0xf2}
  54
  55 /* Amount PC must be decremented by after a breakpoint.
  56    This is often the number of bytes in BREAKPOINT
  57    but not always.  */
  58
  59 #define DECR_PC_AFTER_BREAK 0
  60
  61 /* Define this to say that the "svc" insn is followed by
  62    codes in memory saying which kind of system call it is.  */
  63
  64 #define NS32K_SVC_IMMED_OPERANDS
  65
  66 /* Say how long (ordinary) registers are.  This is a piece of bogosity
  67    used in push_word and a few other places; REGISTER_RAW_SIZE is the
  68    real way to know how big a register is.  */
  69
  70 #define REGISTER_SIZE 4
  71
  72 /* Number of machine registers */
  73
  74 #define NUM_REGS                25
  75
  76 #define NUM_GENERAL_REGS        8
  77
  78 /* Initializer for an array of names of registers.
  79    There should be NUM_REGS strings in this initializer.  */
  80
  81 #define REGISTER_NAMES {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
  82                         "pc", "sp", "fp", "ps",                         \
  83                         "fsr",                                          \
  84                         "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \
  85                         "l0", "l1", "l2", "l3", "l4",                   \
  86                         }
  87
  88 /* Register numbers of various important registers.
  89    Note that some of these values are "real" register numbers,
  90    and correspond to the general registers of the machine,
  91    and some are "phony" register numbers which are too large
  92    to be actual register numbers as far as the user is concerned
  93    but do serve to get the desired values when passed to read_register.  */
  94
  95 #define AP_REGNUM FP_REGNUM
  96 #define FP_REGNUM 10            /* Contains address of executing stack frame */
  97 #define SP_REGNUM 9             /* Contains address of top of stack */
  98 #define PC_REGNUM 8             /* Contains program counter */
  99 #define PS_REGNUM 11            /* Contains processor status */
 100 #define FPS_REGNUM 12           /* Floating point status register */
 101 #define FP0_REGNUM 13           /* Floating point register 0 */
 102 #define LP0_REGNUM 21           /* Double register 0 (same as FP0) */
 103
 104 /* Total amount of space needed to store our copies of the machine's
 105    register state, the array `registers'.  */
 106 #define REGISTER_BYTES ((NUM_REGS - 4) * sizeof (int) + 4 * sizeof (double))
 107
 108 /* Index within `registers' of the first byte of the space for
 109    register N.  */
 110
 111 #define REGISTER_BYTE(N) ((N) >= LP0_REGNUM ? \
 112         LP0_REGNUM * 4 + ((N) - LP0_REGNUM) * 8 : (N) * 4)
 113
 114 /* Number of bytes of storage in the actual machine representation
 115    for register N.  On the 32000, all regs are 4 bytes
 116    except for the doubled floating registers. */
 117
 118 #define REGISTER_RAW_SIZE(N) ((N) >= LP0_REGNUM ? 8 : 4)
 119
 120 /* Number of bytes of storage in the program's representation
 121    for register N.  On the 32000, all regs are 4 bytes
 122    except for the doubled floating registers. */
 123
 124 #define REGISTER_VIRTUAL_SIZE(N) ((N) >= LP0_REGNUM ? 8 : 4)
 125
 126 /* Largest value REGISTER_RAW_SIZE can have.  */
 127
 128 #define MAX_REGISTER_RAW_SIZE 8
 129
 130 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 131
 132 #define MAX_REGISTER_VIRTUAL_SIZE 8
 133
 134 /* Return the GDB type object for the "standard" data type
 135    of data in register N.  */
 136
 137 #define REGISTER_VIRTUAL_TYPE(N) \
 138   ((N) >= FP0_REGNUM ?          \
 139     ((N) >= LP0_REGNUM ?        \
 140      builtin_type_double        \
 141      : builtin_type_float)      \
 142    : builtin_type_int)
 143
 144 /* Store the address of the place in which to copy the structure the
 145    subroutine will return.  This is called from call_function.
 146
 147    On this machine this is a no-op, as gcc doesn't run on it yet.
 148    This calling convention is not used. */
 149
 150 #define STORE_STRUCT_RETURN(ADDR, SP)
 151
 152 /* Extract from an array REGBUF containing the (raw) register state
 153    a function return value of type TYPE, and copy that, in virtual format,
 154    into VALBUF.  */
 155
 156 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 157   memcpy (VALBUF, REGBUF, TYPE_LENGTH (TYPE))
 158
 159 /* Write into appropriate registers a function return value
 160    of type TYPE, given in virtual format.  */
 161
 162 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 163   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 164
 165 /* Extract from an array REGBUF containing the (raw) register state
 166    the address in which a function should return its structure value,
 167    as a CORE_ADDR (or an expression that can be used as one).  */
 168
 169 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 170 \f
 171 /* Describe the pointer in each stack frame to the previous stack frame
 172    (its caller).  */
 173
 174 /* FRAME_CHAIN takes a frame's nominal address
 175    and produces the frame's chain-pointer. */
 176
 177 /* In the case of the Merlin, the frame's nominal address is the FP value,
 178    and at that address is saved previous FP value as a 4-byte word.  */
 179
 180 #define FRAME_CHAIN(thisframe)  \
 181   (!inside_entry_file ((thisframe)->pc) ? \
 182    read_memory_integer ((thisframe)->frame, 4) :\
 183    0)
 184
 185 /* Define other aspects of the stack frame.  */
 186
 187 #define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 4, 4))
 188
 189 /* compute base of arguments */
 190 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 191
 192 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 193
 194 /* Return number of args passed to a frame.
 195    Can return -1, meaning no way to tell.  */
 196
 197 extern int merlin_frame_num_args (struct frame_info *fi);
 198 #define FRAME_NUM_ARGS(fi) (merlin_frame_num_args ((fi)))
 199
 200 /* Return number of bytes at start of arglist that are not really args.  */
 201
 202 #define FRAME_ARGS_SKIP 8
 203
 204 /* Put here the code to store, into a struct frame_saved_regs,
 205    the addresses of the saved registers of frame described by FRAME_INFO.
 206    This includes special registers such as pc and fp saved in special
 207    ways in the stack frame.  sp is even more special:
 208    the address we return for it IS the sp for the next frame.  */
 209
 210 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 211 { int regmask,regnum;                                           \
 212   int localcount;                                               \
 213   CORE_ADDR enter_addr;                                         \
 214   CORE_ADDR next_addr;                                          \
 215                                                                 \
 216   enter_addr = get_pc_function_start ((frame_info)->pc);        \
 217   regmask = read_memory_integer (enter_addr+1, 1);              \
 218   localcount = ns32k_localcount (enter_addr);                   \
 219   next_addr = (frame_info)->frame + localcount;                 \
 220   for (regnum = 0; regnum < 8; regnum++, regmask >>= 1)         \
 221     (frame_saved_regs).regs[regnum]                             \
 222       = (regmask & 1) ? (next_addr -= 4) : 0;                   \
 223   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 4; \
 224   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4; \
 225   (frame_saved_regs).regs[FP_REGNUM]                            \
 226      = read_memory_integer ((frame_info)->frame, 4); }
 227 \f
 228
 229 /* Things needed for making the inferior call functions.  */
 230
 231 /* Push an empty stack frame, to record the current PC, etc.  */
 232
 233 #define PUSH_DUMMY_FRAME \
 234 { register CORE_ADDR sp = read_register (SP_REGNUM);    \
 235   register int regnum;                                  \
 236   sp = push_word (sp, read_register (PC_REGNUM));       \
 237   sp = push_word (sp, read_register (FP_REGNUM));       \
 238   write_register (FP_REGNUM, sp);                       \
 239   for (regnum = 0; regnum < 8; regnum++)                \
 240     sp = push_word (sp, read_register (regnum));        \
 241   write_register (SP_REGNUM, sp);                       \
 242 }
 243
 244 /* Discard from the stack the innermost frame, restoring all registers.  */
 245
 246 #define POP_FRAME  \
 247 { register struct frame_info *frame = get_current_frame ();      \
 248   register CORE_ADDR fp;                                         \
 249   register int regnum;                                           \
 250   struct frame_saved_regs fsr;                                   \
 251   struct frame_info *fi;                                                 \
 252   fp = frame->frame;                                             \
 253   get_frame_saved_regs (frame, &fsr);                            \
 254   for (regnum = 0; regnum < 8; regnum++)                         \
 255     if (fsr.regs[regnum])                                        \
 256       write_register (regnum, read_memory_integer (fsr.regs[regnum], 4)); \
 257   write_register (FP_REGNUM, read_memory_integer (fp, 4));       \
 258   write_register (PC_REGNUM, read_memory_integer (fp + 4, 4));   \
 259   write_register (SP_REGNUM, fp + 8);                            \
 260   flush_cached_frames ();                                        \
 261 }
 262
 263 /* This sequence of words is the instructions
 264    enter        0xff,0          82 ff 00
 265    jsr  @0x00010203     7f ae c0 01 02 03
 266    adjspd       0x69696969      7f a5 01 02 03 04
 267    bpt                  f2
 268    Note this is 16 bytes.  */
 269
 270 #define CALL_DUMMY { 0x7f00ff82, 0x0201c0ae, 0x01a57f03, 0xf2040302 }
 271
 272 #define CALL_DUMMY_START_OFFSET 3
 273 #define CALL_DUMMY_LENGTH       16
 274 #define CALL_DUMMY_ADDR         5
 275 #define CALL_DUMMY_NARGS        11
 276
 277 /* Insert the specified number of args and function address
 278    into a call sequence of the above form stored at DUMMYNAME.  */
 279
 280 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)            \
 281 { int flipped = fun | 0xc0000000;                               \
 282   flip_bytes (&flipped, 4);                                     \
 283   *((int *) (((char *) dummyname)+CALL_DUMMY_ADDR)) = flipped;  \
 284   flipped = - nargs * 4;                                        \
 285   flip_bytes (&flipped, 4);                                     \
 286   *((int *) (((char *) dummyname)+CALL_DUMMY_NARGS)) = flipped; \
 287 }