gdb/config/m68k/tm-isi.h

   1 /* Definitions to target GDB on an ISI Optimum V (3.05) under 4.3bsd.
   2    Copyright (C) 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 /* This has not been tested on ISI's running BSD 4.2, but it will probably
  22    work.  */
  23
  24 /* Data segment starts at etext rounded up to DATAROUND in {N,Z}MAGIC files */
  25
  26 #define DATAROUND       0x20000
  27 #define N_DATADDR(hdr)  (hdr.a_magic != OMAGIC ? \
  28         (hdr.a_text + DATAROUND) & ~(DATAROUND-1) : hdr.a_text)
  29
  30 /* Text segment starts at sizeof (struct exec) in {N,Z}MAGIC files */
  31
  32 #define N_TXTADDR(hdr)  (hdr.a_magic != OMAGIC ? sizeof (struct exec) : 0)
  33
  34 /* Amount PC must be decremented by after a breakpoint.
  35    This is often the number of bytes in BREAKPOINT
  36    but not always.
  37    On the ISI, the kernel resets the pc to the trap instr */
  38
  39 #define DECR_PC_AFTER_BREAK 0
  40 \f
  41
  42 /* Return number of args passed to a frame.
  43    Can return -1, meaning no way to tell.  */
  44
  45 extern int isi_frame_num_args PARAMS ((struct frame_info * fi));
  46 #define FRAME_NUM_ARGS(fi) (isi_frame_num_args ((fi)))
  47
  48 /* Put here the code to store, into a struct frame_saved_regs,
  49    the addresses of the saved registers of frame described by FRAME_INFO.
  50    This includes special registers such as pc and fp saved in special
  51    ways in the stack frame.  sp is even more special:
  52    the address we return for it IS the sp for the next frame.  */
  53
  54 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs)             \
  55 { register int regnum;                                                  \
  56   register int regmask;                                                 \
  57   register CORE_ADDR next_addr;                                         \
  58   register CORE_ADDR pc;                                                \
  59   register int insn;                                                    \
  60   register int offset;                                                  \
  61   memset (&frame_saved_regs, '\0', sizeof frame_saved_regs);                    \
  62   if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 8*12 - 4 \
  63       && (frame_info)->pc <= (frame_info)->frame)                               \
  64     { next_addr = (frame_info)->frame;                                  \
  65       pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 8*12 - 4; }\
  66   else                                                                  \
  67     { pc = get_pc_function_start ((frame_info)->pc);                    \
  68       /* Verify we have a link a6 instruction next,                     \
  69          or a branch followed by a link a6 instruction;                 \
  70          if not we lose.  If we win, find the address above the saved   \
  71          regs using the amount of storage from the link instruction.  */\
  72 retry:                                                                  \
  73       insn = read_memory_integer (pc, 2);                               \
  74       if (insn == 044016)                                               \
  75         next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 4), pc+=4; \
  76       else if (insn == 047126)                                          \
  77         next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 2), pc+=2; \
  78       else if ((insn & 0177400) == 060000)      /* bra insn */          \
  79         { offset = insn & 0377;                                         \
  80           pc += 2;                              /* advance past bra */  \
  81           if (offset == 0)                      /* bra #word */         \
  82             offset = read_memory_integer (pc, 2), pc += 2;              \
  83           else if (offset == 0377)              /* bra #long */         \
  84             offset = read_memory_integer (pc, 4), pc += 4;              \
  85           pc += offset;                                                 \
  86           goto retry;                                                   \
  87       } else goto lose;                                                 \
  88       /* If have an addal #-n, sp next, adjust next_addr.  */           \
  89       if ((0177777 & read_memory_integer (pc, 2)) == 0157774)           \
  90         next_addr += read_memory_integer (pc += 2, 4), pc += 4;         \
  91     }                                                                   \
  92   /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */      \
  93   insn = read_memory_integer (pc, 2), pc += 2;                          \
  94   regmask = read_memory_integer (pc, 2);                                \
  95   if ((insn & 0177760) == 022700)       /* movl rn, (sp) */             \
  96     (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr;   \
  97   else if ((insn & 0177760) == 024700)  /* movl rn, -(sp) */            \
  98     (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr-=4; \
  99   else if (insn == 0044327)             /* moveml mask, (sp) */         \
 100     { pc += 2;                                                          \
 101       /* Regmask's low bit is for register 0, the first written */      \
 102       next_addr -= 4;                                                   \
 103       for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)            \
 104         if (regmask & 1)                                                \
 105           (frame_saved_regs).regs[regnum] = (next_addr += 4);           \
 106   } else if (insn == 0044347)           /* moveml mask, -(sp) */        \
 107     { pc += 2;                                                          \
 108       /* Regmask's low bit is for register 15, the first pushed */      \
 109       for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1)           \
 110         if (regmask & 1)                                                \
 111           (frame_saved_regs).regs[regnum] = (next_addr -= 4); }         \
 112   /* clrw -(sp); movw ccr,-(sp) may follow.  */                         \
 113   if (read_memory_integer (pc, 2) == 041147                             \
 114       && read_memory_integer (pc+2, 2) == 042347)                       \
 115     (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4);              \
 116   lose: ;                                                               \
 117   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8;         \
 118   (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame;             \
 119   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4;         \
 120 }
 121
 122 /* The only reason this is here is the tm-isi.h reference below.  It
 123    was moved back here from tm-m68k.h.  FIXME? */
 124
 125 extern CORE_ADDR isi_skip_prologue PARAMS ((CORE_ADDR));
 126 #define SKIP_PROLOGUE(pc) (isi_skip_prologue (pc))
 127
 128 #include "m68k/tm-m68k.h"