gdb/config/m68k/tm-isi.h

   1 /* Definitions to target GDB on an ISI Optimum V (3.05) under 4.3bsd.
   2    Copyright 1987, 1989, 1991, 1993, 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 /* This has not been tested on ISI's running BSD 4.2, but it will probably
  23    work.  */
  24
  25 /* Data segment starts at etext rounded up to DATAROUND in {N,Z}MAGIC files */
  26
  27 #define DATAROUND       0x20000
  28 #define N_DATADDR(hdr)  (hdr.a_magic != OMAGIC ? \
  29         (hdr.a_text + DATAROUND) & ~(DATAROUND-1) : hdr.a_text)
  30
  31 /* Text segment starts at sizeof (struct exec) in {N,Z}MAGIC files */
  32
  33 #define N_TXTADDR(hdr)  (hdr.a_magic != OMAGIC ? sizeof (struct exec) : 0)
  34
  35 /* Amount PC must be decremented by after a breakpoint.
  36    This is often the number of bytes in BREAKPOINT
  37    but not always.
  38    On the ISI, the kernel resets the pc to the trap instr */
  39
  40 #define DECR_PC_AFTER_BREAK 0
  41 \f
  42
  43 /* Return number of args passed to a frame.
  44    Can return -1, meaning no way to tell.  */
  45
  46 extern int isi_frame_num_args (struct frame_info *fi);
  47 #define FRAME_NUM_ARGS(fi) (isi_frame_num_args ((fi)))
  48
  49 /* Put here the code to store, into a struct frame_saved_regs,
  50    the addresses of the saved registers of frame described by FRAME_INFO.
  51    This includes special registers such as pc and fp saved in special
  52    ways in the stack frame.  sp is even more special:
  53    the address we return for it IS the sp for the next frame.  */
  54
  55 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs)             \
  56 { register int regnum;                                                  \
  57   register int regmask;                                                 \
  58   register CORE_ADDR next_addr;                                         \
  59   register CORE_ADDR pc;                                                \
  60   register int insn;                                                    \
  61   register int offset;                                                  \
  62   memset (&frame_saved_regs, '\0', sizeof frame_saved_regs);                    \
  63   if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 8*12 - 4 \
  64       && (frame_info)->pc <= (frame_info)->frame)                               \
  65     { next_addr = (frame_info)->frame;                                  \
  66       pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 8*12 - 4; }\
  67   else                                                                  \
  68     { pc = get_pc_function_start ((frame_info)->pc);                    \
  69       /* Verify we have a link a6 instruction next,                     \
  70          or a branch followed by a link a6 instruction;                 \
  71          if not we lose.  If we win, find the address above the saved   \
  72          regs using the amount of storage from the link instruction.  */\
  73 retry:                                                                  \
  74       insn = read_memory_integer (pc, 2);                               \
  75       if (insn == 044016)                                               \
  76         next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 4), pc+=4; \
  77       else if (insn == 047126)                                          \
  78         next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 2), pc+=2; \
  79       else if ((insn & 0177400) == 060000)      /* bra insn */          \
  80         { offset = insn & 0377;                                         \
  81           pc += 2;                              /* advance past bra */  \
  82           if (offset == 0)                      /* bra #word */         \
  83             offset = read_memory_integer (pc, 2), pc += 2;              \
  84           else if (offset == 0377)              /* bra #long */         \
  85             offset = read_memory_integer (pc, 4), pc += 4;              \
  86           pc += offset;                                                 \
  87           goto retry;                                                   \
  88       } else goto lose;                                                 \
  89       /* If have an addal #-n, sp next, adjust next_addr.  */           \
  90       if ((0177777 & read_memory_integer (pc, 2)) == 0157774)           \
  91         next_addr += read_memory_integer (pc += 2, 4), pc += 4;         \
  92     }                                                                   \
  93   /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */      \
  94   insn = read_memory_integer (pc, 2), pc += 2;                          \
  95   regmask = read_memory_integer (pc, 2);                                \
  96   if ((insn & 0177760) == 022700)       /* movl rn, (sp) */             \
  97     (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr;   \
  98   else if ((insn & 0177760) == 024700)  /* movl rn, -(sp) */            \
  99     (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr-=4; \
 100   else if (insn == 0044327)             /* moveml mask, (sp) */         \
 101     { pc += 2;                                                          \
 102       /* Regmask's low bit is for register 0, the first written */      \
 103       next_addr -= 4;                                                   \
 104       for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)            \
 105         if (regmask & 1)                                                \
 106           (frame_saved_regs).regs[regnum] = (next_addr += 4);           \
 107   } else if (insn == 0044347)           /* moveml mask, -(sp) */        \
 108     { pc += 2;                                                          \
 109       /* Regmask's low bit is for register 15, the first pushed */      \
 110       for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1)           \
 111         if (regmask & 1)                                                \
 112           (frame_saved_regs).regs[regnum] = (next_addr -= 4); }         \
 113   /* clrw -(sp); movw ccr,-(sp) may follow.  */                         \
 114   if (read_memory_integer (pc, 2) == 041147                             \
 115       && read_memory_integer (pc+2, 2) == 042347)                       \
 116     (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4);              \
 117   lose: ;                                                               \
 118   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8;         \
 119   (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame;             \
 120   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4;         \
 121 }
 122
 123 /* The only reason this is here is the tm-isi.h reference below.  It
 124    was moved back here from tm-m68k.h.  FIXME? */
 125
 126 extern CORE_ADDR isi_skip_prologue (CORE_ADDR);
 127 #define SKIP_PROLOGUE(pc) (isi_skip_prologue (pc))
 128
 129 #include "m68k/tm-m68k.h"