| 1 | /* Definitions to target GDB on an ISI Optimum V (3.05) under 4.3bsd. |
| 2 | Copyright (C) 1987, 1989, 1991 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 | /* Address of end of stack space. */ |
| 31 | |
| 32 | #define STACK_END_ADDR 0xfffe000 |
| 33 | |
| 34 | /* Data segment starts at etext rounded up to DATAROUND in {N,Z}MAGIC files */ |
| 35 | |
| 36 | #define DATAROUND 0x20000 |
| 37 | #define N_DATADDR(hdr) (hdr.a_magic != OMAGIC ? \ |
| 38 | (hdr.a_text + DATAROUND) & ~(DATAROUND-1) : hdr.a_text) |
| 39 | |
| 40 | /* Text segment starts at sizeof (struct exec) in {N,Z}MAGIC files */ |
| 41 | |
| 42 | #define N_TXTADDR(hdr) (hdr.a_magic != OMAGIC ? sizeof (struct exec) : 0) |
| 43 | |
| 44 | /* Amount PC must be decremented by after a breakpoint. |
| 45 | This is often the number of bytes in BREAKPOINT |
| 46 | but not always. |
| 47 | On the ISI, the kernel resets the pc to the trap instr */ |
| 48 | |
| 49 | #define DECR_PC_AFTER_BREAK 0 |
| 50 | |
| 51 | \f |
| 52 | /* Return number of args passed to a frame. |
| 53 | Can return -1, meaning no way to tell. */ |
| 54 | |
| 55 | #define FRAME_NUM_ARGS(val, fi) \ |
| 56 | { register CORE_ADDR pc = FRAME_SAVED_PC (fi); \ |
| 57 | register int insn = 0177777 & read_memory_integer (pc, 2); \ |
| 58 | val = 0; \ |
| 59 | if (insn == 0047757 || insn == 0157374) /* lea W(sp),sp or addaw #W,sp */ \ |
| 60 | val = read_memory_integer (pc + 2, 2); \ |
| 61 | else if ((insn & 0170777) == 0050217 /* addql #N, sp */ \ |
| 62 | || (insn & 0170777) == 0050117) /* addqw */ \ |
| 63 | { val = (insn >> 9) & 7; if (val == 0) val = 8; } \ |
| 64 | else if (insn == 0157774) /* addal #WW, sp */ \ |
| 65 | val = read_memory_integer (pc + 2, 4); \ |
| 66 | val >>= 2; } |
| 67 | |
| 68 | /* Put here the code to store, into a struct frame_saved_regs, |
| 69 | the addresses of the saved registers of frame described by FRAME_INFO. |
| 70 | This includes special registers such as pc and fp saved in special |
| 71 | ways in the stack frame. sp is even more special: |
| 72 | the address we return for it IS the sp for the next frame. */ |
| 73 | |
| 74 | #define FRAME_FIND_SAVED_REGS(frame_info, frame_saved_regs) \ |
| 75 | { register int regnum; \ |
| 76 | register int regmask; \ |
| 77 | register CORE_ADDR next_addr; \ |
| 78 | register CORE_ADDR pc; \ |
| 79 | register int insn; \ |
| 80 | register int offset; \ |
| 81 | bzero (&frame_saved_regs, sizeof frame_saved_regs); \ |
| 82 | if ((frame_info)->pc >= (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 8*12 - 4 \ |
| 83 | && (frame_info)->pc <= (frame_info)->frame) \ |
| 84 | { next_addr = (frame_info)->frame; \ |
| 85 | pc = (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM * 4 - 8*12 - 4; }\ |
| 86 | else \ |
| 87 | { pc = get_pc_function_start ((frame_info)->pc); \ |
| 88 | /* Verify we have a link a6 instruction next, \ |
| 89 | or a branch followed by a link a6 instruction; \ |
| 90 | if not we lose. If we win, find the address above the saved \ |
| 91 | regs using the amount of storage from the link instruction. */\ |
| 92 | retry: \ |
| 93 | insn = read_memory_integer (pc, 2); \ |
| 94 | if (insn == 044016) \ |
| 95 | next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 4), pc+=4; \ |
| 96 | else if (insn == 047126) \ |
| 97 | next_addr = (frame_info)->frame - read_memory_integer (pc += 2, 2), pc+=2; \ |
| 98 | else if ((insn & 0177400) == 060000) /* bra insn */ \ |
| 99 | { offset = insn & 0377; \ |
| 100 | pc += 2; /* advance past bra */ \ |
| 101 | if (offset == 0) /* bra #word */ \ |
| 102 | offset = read_memory_integer (pc, 2), pc += 2; \ |
| 103 | else if (offset == 0377) /* bra #long */ \ |
| 104 | offset = read_memory_integer (pc, 4), pc += 4; \ |
| 105 | pc += offset; \ |
| 106 | goto retry; \ |
| 107 | } else goto lose; \ |
| 108 | /* If have an addal #-n, sp next, adjust next_addr. */ \ |
| 109 | if ((0177777 & read_memory_integer (pc, 2)) == 0157774) \ |
| 110 | next_addr += read_memory_integer (pc += 2, 4), pc += 4; \ |
| 111 | } \ |
| 112 | /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */ \ |
| 113 | insn = read_memory_integer (pc, 2), pc += 2; \ |
| 114 | regmask = read_memory_integer (pc, 2); \ |
| 115 | if ((insn & 0177760) == 022700) /* movl rn, (sp) */ \ |
| 116 | (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr; \ |
| 117 | else if ((insn & 0177760) == 024700) /* movl rn, -(sp) */ \ |
| 118 | (frame_saved_regs).regs[(insn&7) + ((insn&010)?8:0)] = next_addr-=4; \ |
| 119 | else if (insn == 0044327) /* moveml mask, (sp) */ \ |
| 120 | { pc += 2; \ |
| 121 | /* Regmask's low bit is for register 0, the first written */ \ |
| 122 | next_addr -= 4; \ |
| 123 | for (regnum = 0; regnum < 16; regnum++, regmask >>= 1) \ |
| 124 | if (regmask & 1) \ |
| 125 | (frame_saved_regs).regs[regnum] = (next_addr += 4); \ |
| 126 | } else if (insn == 0044347) /* moveml mask, -(sp) */ \ |
| 127 | { pc += 2; \ |
| 128 | /* Regmask's low bit is for register 15, the first pushed */ \ |
| 129 | for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1) \ |
| 130 | if (regmask & 1) \ |
| 131 | (frame_saved_regs).regs[regnum] = (next_addr -= 4); } \ |
| 132 | /* clrw -(sp); movw ccr,-(sp) may follow. */ \ |
| 133 | if (read_memory_integer (pc, 2) == 041147 \ |
| 134 | && read_memory_integer (pc+2, 2) == 042347) \ |
| 135 | (frame_saved_regs).regs[PS_REGNUM] = (next_addr -= 4); \ |
| 136 | lose: ; \ |
| 137 | (frame_saved_regs).regs[SP_REGNUM] = (frame_info)->frame + 8; \ |
| 138 | (frame_saved_regs).regs[FP_REGNUM] = (frame_info)->frame; \ |
| 139 | (frame_saved_regs).regs[PC_REGNUM] = (frame_info)->frame + 4; \ |
| 140 | } |
| 141 | |
| 142 | /* The only reason this is here is the tm-isi.h reference below. It |
| 143 | was moved back here from tm-68k.h. FIXME? */ |
| 144 | |
| 145 | #define SKIP_PROLOGUE(pc) \ |
| 146 | { register int op = read_memory_integer (pc, 2); \ |
| 147 | if (op == 0047126) \ |
| 148 | pc += 4; /* Skip link #word */ \ |
| 149 | else if (op == 0044016) \ |
| 150 | pc += 6; /* Skip link #long */ \ |
| 151 | /* Not sure why branches are here. */ \ |
| 152 | /* From tm-isi.h, tm-altos.h */ \ |
| 153 | else if (op == 0060000) \ |
| 154 | pc += 4; /* Skip bra #word */ \ |
| 155 | else if (op == 00600377) \ |
| 156 | pc += 6; /* skip bra #long */ \ |
| 157 | else if ((op & 0177400) == 0060000) \ |
| 158 | pc += 2; /* skip bra #char */ \ |
| 159 | } |
| 160 | |
| 161 | #include "tm-68k.h" |