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