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