gdb/tm-isi.h

   1 /* Definitions to target GDB on an ISI Optimum V (3.05) under 4.3bsd.
   2    Copyright (C) 1987, 1989 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., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 /* This has not been tested on ISI's running BSD 4.2, but it will probably
  21    work.  */
  22
  23 #define HAVE_68881
  24
  25 /* Define this if the C compiler puts an underscore at the front
  26    of external names before giving them to the linker.  */
  27
  28 #define NAMES_HAVE_UNDERSCORE
  29
  30 /* Debugger information will be in DBX format.  */
  31
  32 #define READ_DBX_FORMAT
  33
  34 /* Address of end of stack space.  */
  35
  36 #define STACK_END_ADDR 0xfffe000
  37
  38 /* Data segment starts at etext rounded up to DATAROUND in {N,Z}MAGIC files */
  39
  40 #define DATAROUND       0x20000
  41 #define N_DATADDR(hdr)  (hdr.a_magic != OMAGIC ? \
  42         (hdr.a_text + DATAROUND) & ~(DATAROUND-1) : hdr.a_text)
  43
  44 /* Text segment starts at sizeof (struct exec) in {N,Z}MAGIC files */
  45
  46 #define N_TXTADDR(hdr)  (hdr.a_magic != OMAGIC ? sizeof (struct exec) : 0)
  47
  48 /* Amount PC must be decremented by after a breakpoint.
  49    This is often the number of bytes in BREAKPOINT
  50    but not always.
  51    On the ISI, the kernel resets the pc to the trap instr */
  52
  53 #define DECR_PC_AFTER_BREAK 0
  54
  55 \f
  56 /* Return number of args passed to a frame.
  57    Can return -1, meaning no way to tell.  */
  58
  59 #define FRAME_NUM_ARGS(val, fi)  \
  60 { register CORE_ADDR pc = FRAME_SAVED_PC (fi);                  \
  61   register int insn = 0177777 & read_memory_integer (pc, 2);    \
  62   val = 0;                                                      \
  63   if (insn == 0047757 || insn == 0157374)  /* lea W(sp),sp or addaw #W,sp */ \
  64     val = read_memory_integer (pc + 2, 2);                      \
  65   else if ((insn & 0170777) == 0050217 /* addql #N, sp */       \
  66            || (insn & 0170777) == 0050117)  /* addqw */         \
  67     { val = (insn >> 9) & 7; if (val == 0) val = 8; }           \
  68   else if (insn == 0157774) /* addal #WW, sp */                 \
  69     val = read_memory_integer (pc + 2, 4);                      \
  70   val >>= 2; }
  71
  72 /* Put here the code to store, into a struct frame_saved_regs,
  73    the addresses of the saved registers of frame described by FRAME_INFO.
  74    This includes special registers such as pc and fp saved in special
  75    ways in the stack frame.  sp is even more special:
  76    the address we return for it IS the sp for the next frame.  */
  77
  78 #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs)             \
  79 { register int regnum;                                                  \
  80   register int regmask;                                                 \
  81   register CORE_ADDR next_addr;                                         \
  82   register CORE_ADDR pc;                                                \
  83   register int insn;                                                    \
  84   register int offset;                                                  \
  85   bzero (&frame_saved_regs, sizeof frame_saved_regs);                   \
  86   if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 8*12 - 4 \
  87       && (frame_info)->pc <= (frame_info)->frame)                               \
  88     { next_addr = (frame_info)->frame;                                  \
  89       pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 8*12 - 4; }\
  90   else                                                                  \
  91     { pc = get_pc_function_start ((frame_info)->pc);                    \
  92       /* Verify we have a link a6 instruction next,                     \
  93          or a branch followed by a link a6 instruction;                 \
  94          if not we lose.  If we win, find the address above the saved   \
  95          regs using the amount of storage from the link instruction.  */\
  96 retry:                                                                  \
  97       insn = read_memory_integer (pc, 2);                               \
  98       if (insn == 044016)                                               \
  99         next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 4), pc+=4; \
 100       else if (insn == 047126)                                          \
 101         next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 2), pc+=2; \
 102       else if ((insn & 0177400) == 060000)      /* bra insn */          \
 103         { offset = insn & 0377;                                         \
 104           pc += 2;                              /* advance past bra */  \
 105           if (offset == 0)                      /* bra #word */         \
 106             offset = read_memory_integer (pc, 2), pc += 2;              \
 107           else if (offset == 0377)              /* bra #long */         \
 108             offset = read_memory_integer (pc, 4), pc += 4;              \
 109           pc += offset;                                                 \
 110           goto retry;                                                   \
 111       } else goto lose;                                                 \
 112       /* If have an addal #-n, sp next, adjust next_addr.  */           \
 113       if ((0177777 & read_memory_integer (pc, 2)) == 0157774)           \
 114         next_addr += read_memory_integer (pc += 2, 4), pc += 4;         \
 115     }                                                                   \
 116   /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */      \
 117   insn = read_memory_integer (pc, 2), pc += 2;                          \
 118   regmask = read_memory_integer (pc, 2);                                \
 119   if ((insn & 0177760) == 022700)       /* movl rn, (sp) */             \
 120     (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr;   \
 121   else if ((insn & 0177760) == 024700)  /* movl rn, -(sp) */            \
 122     (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr-=4; \
 123   else if (insn == 0044327)             /* moveml mask, (sp) */         \
 124     { pc += 2;                                                          \
 125       /* Regmask's low bit is for register 0, the first written */      \
 126       next_addr -= 4;                                                   \
 127       for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)            \
 128         if (regmask & 1)                                                \
 129           (frame_saved_regs).regs[regnum] = (next_addr += 4);           \
 130   } else if (insn == 0044347)           /* moveml mask, -(sp) */        \
 131     { pc += 2;                                                          \
 132       /* Regmask's low bit is for register 15, the first pushed */      \
 133       for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1)           \
 134         if (regmask & 1)                                                \
 135           (frame_saved_regs).regs[regnum] = (next_addr -= 4); }         \
 136   /* clrw -(sp); movw ccr,-(sp) may follow.  */                         \
 137   if (read_memory_integer (pc, 2) == 041147                             \
 138       && read_memory_integer (pc+2, 2) == 042347)                       \
 139     (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4);              \
 140   lose: ;                                                               \
 141   (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8;         \
 142   (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame;             \
 143   (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4;         \
 144 }
 145
 146 #include "tm-68k.h"