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 Free Software Foundation, Inc.
   3
   4 This file is part of GDB.
   5
   6 This program is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or
   9 (at your option) any later version.
  10
  11 This program is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #define TARGET_BYTE_ORDER LITTLE_ENDIAN
  21
  22 /* Offset from address of function to start of its code.
  23    Zero on most machines.  */
  24
  25 #define FUNCTION_START_OFFSET 0
  26
  27 /* Advance PC across any function entry prologue instructions
  28    to reach some "real" code.  */
  29
  30 #define SKIP_PROLOGUE(pc)                               \
  31 { register int op = read_memory_integer (pc, 1);        \
  32   if (op == 0x82)                                       \
  33     { op = read_memory_integer (pc+2,1);                \
  34       if ((op & 0x80) == 0) pc += 3;                    \
  35       else if ((op & 0xc0) == 0x80) pc += 4;            \
  36       else pc += 6;                                     \
  37     }}
  38
  39 /* Immediately after a function call, return the saved pc.
  40    Can't always go through the frames for this because on some machines
  41    the new frame is not set up until the new function executes
  42    some instructions.  */
  43
  44 #define SAVED_PC_AFTER_CALL(frame) \
  45         read_memory_integer (read_register (SP_REGNUM), 4)
  46
  47 /* Address of end of stack space.  */
  48
  49 #define STACK_END_ADDR (0x800000)
  50
  51 /* Stack grows downward.  */
  52
  53 #define INNER_THAN(lhs,rhs) ((lhs) < (rhs))
  54
  55 /* Sequence of bytes for breakpoint instruction.  */
  56
  57 #define BREAKPOINT {0xf2}
  58
  59 /* Amount PC must be decremented by after a breakpoint.
  60    This is often the number of bytes in BREAKPOINT
  61    but not always.  */
  62
  63 #define DECR_PC_AFTER_BREAK 0
  64
  65 /* Define this to say that the "svc" insn is followed by
  66    codes in memory saying which kind of system call it is.  */
  67
  68 #define NS32K_SVC_IMMED_OPERANDS
  69
  70 /* Say how long (ordinary) registers are.  This is a piece of bogosity
  71    used in push_word and a few other places; REGISTER_RAW_SIZE is the
  72    real way to know how big a register is.  */
  73
  74 #define REGISTER_SIZE 4
  75
  76 /* Number of machine registers */
  77
  78 #define NUM_REGS                25
  79
  80 #define NUM_GENERAL_REGS        8
  81
  82 /* Initializer for an array of names of registers.
  83    There should be NUM_REGS strings in this initializer.  */
  84
  85 #define REGISTER_NAMES {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
  86                         "pc", "sp", "fp", "ps",                         \
  87                         "fsr",                                          \
  88                         "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \
  89                         "l0", "l1", "l2", "l3", "l4",                   \
  90                         }
  91
  92 /* Register numbers of various important registers.
  93    Note that some of these values are "real" register numbers,
  94    and correspond to the general registers of the machine,
  95    and some are "phony" register numbers which are too large
  96    to be actual register numbers as far as the user is concerned
  97    but do serve to get the desired values when passed to read_register.  */
  98
  99 #define AP_REGNUM FP_REGNUM
 100 #define FP_REGNUM 10            /* Contains address of executing stack frame */
 101 #define SP_REGNUM 9             /* Contains address of top of stack */
 102 #define PC_REGNUM 8             /* Contains program counter */
 103 #define PS_REGNUM 11            /* Contains processor status */
 104 #define FPS_REGNUM 12           /* Floating point status register */
 105 #define FP0_REGNUM 13           /* Floating point register 0 */
 106 #define LP0_REGNUM 21           /* Double register 0 (same as FP0) */
 107
 108 /* Total amount of space needed to store our copies of the machine's
 109    register state, the array `registers'.  */
 110 #define REGISTER_BYTES ((NUM_REGS - 4) * sizeof (int) + 4 * sizeof (double))
 111
 112 /* Index within `registers' of the first byte of the space for
 113    register N.  */
 114
 115 #define REGISTER_BYTE(N) ((N) >= LP0_REGNUM ? \
 116         LP0_REGNUM * 4 + ((N) - LP0_REGNUM) * 8 : (N) * 4)
 117
 118 /* Number of bytes of storage in the actual machine representation
 119    for register N.  On the 32000, all regs are 4 bytes
 120    except for the doubled floating registers. */
 121
 122 #define REGISTER_RAW_SIZE(N) ((N) >= LP0_REGNUM ? 8 : 4)
 123
 124 /* Number of bytes of storage in the program's representation
 125    for register N.  On the 32000, all regs are 4 bytes
 126    except for the doubled floating registers. */
 127
 128 #define REGISTER_VIRTUAL_SIZE(N) ((N) >= LP0_REGNUM ? 8 : 4)
 129
 130 /* Largest value REGISTER_RAW_SIZE can have.  */
 131
 132 #define MAX_REGISTER_RAW_SIZE 8
 133
 134 /* Largest value REGISTER_VIRTUAL_SIZE can have.  */
 135
 136 #define MAX_REGISTER_VIRTUAL_SIZE 8
 137
 138 /* Return the GDB type object for the "standard" data type
 139    of data in register N.  */
 140
 141 #define REGISTER_VIRTUAL_TYPE(N) \
 142   ((N) >= FP0_REGNUM ?          \
 143     ((N) >= LP0_REGNUM ?        \
 144      builtin_type_double        \
 145      : builtin_type_float)      \
 146    : builtin_type_int)
 147
 148 /* Store the address of the place in which to copy the structure the
 149    subroutine will return.  This is called from call_function.
 150
 151    On this machine this is a no-op, as gcc doesn't run on it yet.
 152    This calling convention is not used. */
 153
 154 #define STORE_STRUCT_RETURN(ADDR, SP)
 155
 156 /* Extract from an array REGBUF containing the (raw) register state
 157    a function return value of type TYPE, and copy that, in virtual format,
 158    into VALBUF.  */
 159
 160 #define EXTRACT_RETURN_VALUE(TYPE,REGBUF,VALBUF) \
 161   memcpy (VALBUF, REGBUF, TYPE_LENGTH (TYPE))
 162
 163 /* Write into appropriate registers a function return value
 164    of type TYPE, given in virtual format.  */
 165
 166 #define STORE_RETURN_VALUE(TYPE,VALBUF) \
 167   write_register_bytes (0, VALBUF, TYPE_LENGTH (TYPE))
 168
 169 /* Extract from an array REGBUF containing the (raw) register state
 170    the address in which a function should return its structure value,
 171    as a CORE_ADDR (or an expression that can be used as one).  */
 172
 173 #define EXTRACT_STRUCT_VALUE_ADDRESS(REGBUF) (*(int *)(REGBUF))
 174 \f
 175 /* Describe the pointer in each stack frame to the previous stack frame
 176    (its caller).  */
 177
 178 /* FRAME_CHAIN takes a frame's nominal address
 179    and produces the frame's chain-pointer. */
 180
 181 /* In the case of the Merlin, the frame's nominal address is the FP value,
 182    and at that address is saved previous FP value as a 4-byte word.  */
 183
 184 #define FRAME_CHAIN(thisframe)  \
 185   (!inside_entry_file ((thisframe)->pc) ? \
 186    read_memory_integer ((thisframe)->frame, 4) :\
 187    0)
 188
 189 /* Define other aspects of the stack frame.  */
 190
 191 #define FRAME_SAVED_PC(FRAME) (read_memory_integer ((FRAME)->frame + 4, 4))
 192
 193 /* compute base of arguments */
 194 #define FRAME_ARGS_ADDRESS(fi) ((fi)->frame)
 195
 196 #define FRAME_LOCALS_ADDRESS(fi) ((fi)->frame)
 197
 198 /* Return number of args passed to a frame.
 199    Can return -1, meaning no way to tell.  */
 200
 201 #define FRAME_NUM_ARGS(numargs, fi)                     \
 202 { CORE_ADDR pc;                                         \
 203   int insn;                                             \
 204   int addr_mode;                                        \
 205   int width;                                            \
 206                                                         \
 207   pc = FRAME_SAVED_PC (fi);                             \
 208   insn = read_memory_integer (pc,2);                    \
 209   addr_mode = (insn >> 11) & 0x1f;                      \
 210   insn = insn & 0x7ff;                                  \
 211   if ((insn & 0x7fc) == 0x57c                           \
 212       && addr_mode == 0x14) /* immediate */             \
 213     { if (insn == 0x57c) /* adjspb */                   \
 214         width = 1;                                      \
 215       else if (insn == 0x57d) /* adjspw */              \
 216         width = 2;                                      \
 217       else if (insn == 0x57f) /* adjspd */              \
 218         width = 4;                                      \
 219       numargs = read_memory_integer (pc+2,width);       \
 220       if (width > 1)                                    \
 221         flip_bytes (&numargs, width);                   \
 222       numargs = - sign_extend (numargs, width*8) / 4; } \
 223   else numargs = -1;                                    \
 224 }
 225
 226 /* Return number of bytes at start of arglist that are not really args.  */
 227
 228 #define FRAME_ARGS_SKIP 8
 229
 230 /* Put here the code to store, into a struct frame_saved_regs,
 231    the addresses of the saved registers of frame described by FRAME_INFO.
 232    This includes special registers such as pc and fp saved in special
 233    ways in the stack frame.  sp is even more special:
 234    the address we return for it IS the sp for the next frame.  */
 235
 236 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \
 237 { int regmask,regnum;                                           \
 238   int localcount;                                               \
 239   CORE_ADDR enter_addr;                                         \
 240   CORE_ADDR next_addr;                                          \
 241                                                                 \
 242   enter_addr = get_pc_function_start ((frame_info)->pc);        \
 243   regmask = read_memory_integer (enter_addr+1, 1);              \
 244   localcount = ns32k_localcount (enter_addr);                   \
 245   next_addr = (frame_info)->frame + localcount;                 \
 246   for (regnum = 0; regnum < 8; regnum++, regmask >>= 1)         \
 247     (frame_saved_regs).regs[regnum]                             \
 248       = (regmask & 1) ? (next_addr -= 4) : 0;                   \
 249   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 4; \
 250   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4; \
 251   (frame_saved_regs).regs[FP_REGNUM]                            \
 252      = read_memory_integer ((frame_info)->frame, 4); }
 253
 254 \f
 255 /* Things needed for making the inferior call functions.  */
 256
 257 /* Push an empty stack frame, to record the current PC, etc.  */
 258
 259 #define PUSH_DUMMY_FRAME \
 260 { register CORE_ADDR sp = read_register (SP_REGNUM);    \
 261   register int regnum;                                  \
 262   sp = push_word (sp, read_register (PC_REGNUM));       \
 263   sp = push_word (sp, read_register (FP_REGNUM));       \
 264   write_register (FP_REGNUM, sp);                       \
 265   for (regnum = 0; regnum < 8; regnum++)                \
 266     sp = push_word (sp, read_register (regnum));        \
 267   write_register (SP_REGNUM, sp);                       \
 268 }
 269
 270 /* Discard from the stack the innermost frame, restoring all registers.  */
 271
 272 #define POP_FRAME  \
 273 { register struct frame_info *frame = get_current_frame ();      \
 274   register CORE_ADDR fp;                                         \
 275   register int regnum;                                           \
 276   struct frame_saved_regs fsr;                                   \
 277   struct frame_info *fi;                                                 \
 278   fp = frame->frame;                                             \
 279   get_frame_saved_regs (frame, &fsr);                            \
 280   for (regnum = 0; regnum < 8; regnum++)                         \
 281     if (fsr.regs[regnum])                                        \
 282       write_register (regnum, read_memory_integer (fsr.regs[regnum], 4)); \
 283   write_register (FP_REGNUM, read_memory_integer (fp, 4));       \
 284   write_register (PC_REGNUM, read_memory_integer (fp + 4, 4));   \
 285   write_register (SP_REGNUM, fp + 8);                            \
 286   flush_cached_frames ();                                        \
 287 }
 288
 289 /* This sequence of words is the instructions
 290      enter      0xff,0          82 ff 00
 291      jsr        @0x00010203     7f ae c0 01 02 03
 292      adjspd     0x69696969      7f a5 01 02 03 04
 293      bpt                        f2
 294    Note this is 16 bytes.  */
 295
 296 #define CALL_DUMMY { 0x7f00ff82, 0x0201c0ae, 0x01a57f03, 0xf2040302 }
 297
 298 #define CALL_DUMMY_START_OFFSET 3
 299 #define CALL_DUMMY_LENGTH       16
 300 #define CALL_DUMMY_ADDR         5
 301 #define CALL_DUMMY_NARGS        11
 302
 303 /* Insert the specified number of args and function address
 304    into a call sequence of the above form stored at DUMMYNAME.  */
 305
 306 #define FIX_CALL_DUMMY(dummyname, pc, fun, nargs, args, type, gcc_p)            \
 307 { int flipped = fun | 0xc0000000;                               \
 308   flip_bytes (&flipped, 4);                                     \
 309   *((int *) (((char *) dummyname)+CALL_DUMMY_ADDR)) = flipped;  \
 310   flipped = - nargs * 4;                                        \
 311   flip_bytes (&flipped, 4);                                     \
 312   *((int *) (((char *) dummyname)+CALL_DUMMY_NARGS)) = flipped; \
 313 }