/* Definitions to target GDB on an ISI Optimum V (3.05) under 4.3bsd. Copyright (C) 1987, 1989, 1991, 1993 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* This has not been tested on ISI's running BSD 4.2, but it will probably work. */ /* Data segment starts at etext rounded up to DATAROUND in {N,Z}MAGIC files */ #define DATAROUND 0x20000 #define N_DATADDR(hdr) (hdr.a_magic != OMAGIC ? \ (hdr.a_text + DATAROUND) & ~(DATAROUND-1) : hdr.a_text) /* Text segment starts at sizeof (struct exec) in {N,Z}MAGIC files */ #define N_TXTADDR(hdr) (hdr.a_magic != OMAGIC ? sizeof (struct exec) : 0) /* Amount PC must be decremented by after a breakpoint. This is often the number of bytes in BREAKPOINT but not always. On the ISI, the kernel resets the pc to the trap instr */ #define DECR_PC_AFTER_BREAK 0 /* Return number of args passed to a frame. Can return -1, meaning no way to tell. */ #define FRAME_NUM_ARGS(val, fi) \ { register CORE_ADDR pc = FRAME_SAVED_PC (fi); \ register int insn = 0177777 & read_memory_integer (pc, 2); \ val = 0; \ if (insn == 0047757 || insn == 0157374) /* lea W(sp),sp or addaw #W,sp */ \ val = read_memory_integer (pc + 2, 2); \ else if ((insn & 0170777) == 0050217 /* addql #N, sp */ \ || (insn & 0170777) == 0050117) /* addqw */ \ { val = (insn >> 9) & 7; if (val == 0) val = 8; } \ else if (insn == 0157774) /* addal #WW, sp */ \ val = read_memory_integer (pc + 2, 4); \ val >>= 2; } /* Put here the code to store, into a struct frame_saved_regs, the addresses of the saved registers of frame described by FRAME_INFO. This includes special registers such as pc and fp saved in special ways in the stack frame. sp is even more special: the address we return for it IS the sp for the next frame. */ #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \ { register int regnum; \ register int regmask; \ register CORE_ADDR next_addr; \ register CORE_ADDR pc; \ register int insn; \ register int offset; \ memset (&frame_saved_regs, '\0', sizeof frame_saved_regs); \ if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 8*12 - 4 \ && (frame_info)->pc <= (frame_info)->frame) \ { next_addr = (frame_info)->frame; \ pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 8*12 - 4; }\ else \ { pc = get_pc_function_start ((frame_info)->pc); \ /* Verify we have a link a6 instruction next, \ or a branch followed by a link a6 instruction; \ if not we lose. If we win, find the address above the saved \ regs using the amount of storage from the link instruction. */\ retry: \ insn = read_memory_integer (pc, 2); \ if (insn == 044016) \ next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 4), pc+=4; \ else if (insn == 047126) \ next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 2), pc+=2; \ else if ((insn & 0177400) == 060000) /* bra insn */ \ { offset = insn & 0377; \ pc += 2; /* advance past bra */ \ if (offset == 0) /* bra #word */ \ offset = read_memory_integer (pc, 2), pc += 2; \ else if (offset == 0377) /* bra #long */ \ offset = read_memory_integer (pc, 4), pc += 4; \ pc += offset; \ goto retry; \ } else goto lose; \ /* If have an addal #-n, sp next, adjust next_addr. */ \ if ((0177777 & read_memory_integer (pc, 2)) == 0157774) \ next_addr += read_memory_integer (pc += 2, 4), pc += 4; \ } \ /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */ \ insn = read_memory_integer (pc, 2), pc += 2; \ regmask = read_memory_integer (pc, 2); \ if ((insn & 0177760) == 022700) /* movl rn, (sp) */ \ (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr; \ else if ((insn & 0177760) == 024700) /* movl rn, -(sp) */ \ (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr-=4; \ else if (insn == 0044327) /* moveml mask, (sp) */ \ { pc += 2; \ /* Regmask's low bit is for register 0, the first written */ \ next_addr -= 4; \ for (regnum = 0; regnum < 16; regnum++, regmask >>= 1) \ if (regmask & 1) \ (frame_saved_regs).regs[regnum] = (next_addr += 4); \ } else if (insn == 0044347) /* moveml mask, -(sp) */ \ { pc += 2; \ /* Regmask's low bit is for register 15, the first pushed */ \ for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1) \ if (regmask & 1) \ (frame_saved_regs).regs[regnum] = (next_addr -= 4); } \ /* clrw -(sp); movw ccr,-(sp) may follow. */ \ if (read_memory_integer (pc, 2) == 041147 \ && read_memory_integer (pc+2, 2) == 042347) \ (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4); \ lose: ; \ (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8; \ (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame; \ (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4; \ } /* The only reason this is here is the tm-isi.h reference below. It was moved back here from tm-m68k.h. FIXME? */ #define SKIP_PROLOGUE(pc) \ { register int op = read_memory_integer (pc, 2); \ if (op == 0047126) \ pc += 4; /* Skip link #word */ \ else if (op == 0044016) \ pc += 6; /* Skip link #long */ \ /* Not sure why branches are here. */ \ /* From tm-isi.h, tm-altos.h */ \ else if (op == 0060000) \ pc += 4; /* Skip bra #word */ \ else if (op == 00600377) \ pc += 6; /* skip bra #long */ \ else if ((op & 0177400) == 0060000) \ pc += 2; /* skip bra #char */ \ } #include "m68k/tm-m68k.h"