| /* Target-machine dependent code for WDC-65816, for GDB. |
| Copyright (C) 1995 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., 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| /* |
| Contributed by Steve Chamberlain |
| sac@cygnus.com |
| */ |
| |
| #include "defs.h" |
| #include "frame.h" |
| #include "obstack.h" |
| #include "symtab.h" |
| #include "gdbcmd.h" |
| #include "gdbtypes.h" |
| #include "dis-asm.h" |
| #include "gdbcore.h" |
| |
| /* Return the saved PC from this frame. */ |
| |
| |
| CORE_ADDR |
| w65_frame_saved_pc (frame) |
| struct frame_info *frame; |
| { |
| return (read_memory_integer (frame->frame + 2, 4) & 0xffffff); |
| } |
| |
| CORE_ADDR |
| w65_addr_bits_remove (addr) |
| CORE_ADDR addr; |
| { |
| return ((addr) & 0xffffff); |
| } |
| |
| read_memory_pointer (x) |
| CORE_ADDR x; |
| { |
| return read_memory_integer (ADDR_BITS_REMOVE (x), 4); |
| } |
| |
| init_frame_pc () |
| { |
| abort (); |
| } |
| |
| void |
| w65_push_dummy_frame () |
| { |
| abort (); |
| } |
| |
| /* 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. |
| |
| We cache the result of doing this in the frame_cache_obstack, since |
| it is fairly expensive. */ |
| |
| void |
| frame_find_saved_regs (fip, fsrp) |
| struct frame_info *fip; |
| struct frame_saved_regs *fsrp; |
| { |
| int locals; |
| CORE_ADDR pc; |
| CORE_ADDR adr; |
| int i; |
| |
| memset (fsrp, 0, sizeof *fsrp); |
| } |
| |
| int |
| saved_pc_after_call () |
| { |
| int sp = read_register (SP_REGNUM); |
| int val = read_memory_integer (sp + 1, 4); |
| return ADDR_BITS_REMOVE (val); |
| } |
| |
| |
| extract_return_value (type, regbuf, valbuf) |
| struct type *type; |
| char *regbuf; |
| char *valbuf; |
| { |
| int b; |
| int len = TYPE_LENGTH (type); |
| |
| for (b = 0; b < len; b += 2) |
| { |
| int todo = len - b; |
| if (todo > 2) |
| todo = 2; |
| memcpy (valbuf + b, regbuf + b, todo); |
| } |
| } |
| |
| void |
| write_return_value (type, valbuf) |
| struct type *type; |
| char *valbuf; |
| { |
| int reg; |
| int len; |
| for (len = 0; len < TYPE_LENGTH (type); len += 2) |
| { |
| write_register_bytes (REGISTER_BYTE (len / 2 + 2), valbuf + len, 2); |
| } |
| } |
| |
| void |
| store_struct_return (addr, sp) |
| CORE_ADDR addr; |
| CORE_ADDR sp; |
| { |
| write_register (2, addr); |
| } |
| |
| void |
| w65_pop_frame () |
| { |
| } |
| |
| init_extra_frame_info () |
| { |
| } |
| |
| pop_frame () |
| { |
| } |
| |
| w65_frame_chain (thisframe) |
| struct frame_info *thisframe; |
| { |
| return 0xffff & read_memory_integer ((thisframe)->frame, 2); |
| } |
| |
| static int |
| gb (x) |
| { |
| return read_memory_integer (x, 1) & 0xff; |
| } |
| |
| extern CORE_ADDR |
| w65_skip_prologue (pc) |
| CORE_ADDR pc; |
| { |
| CORE_ADDR too_far = pc + 20; |
| |
| /* looking for bits of the prologue, we can expect to |
| see this in a frameful function: |
| |
| stack adjust: |
| |
| 3B tsc |
| 1A inc a |
| 18 clc |
| 69E2FF adc #0xffe2 |
| 3A dec a |
| 1B tcs |
| 1A inc a |
| |
| link: |
| |
| A500 lda <r15 |
| 48 pha |
| 3B tsc |
| 1a inc a |
| 8500 sta <r15 |
| |
| */ |
| |
| #define TSC 0x3b |
| #define TCS 0x1b |
| #define INCA 0x1a |
| #define PHA 0x48 |
| #define LDADIR 0xa5 |
| #define STADIR 0x85 |
| |
| /* Skip a stack adjust - any area between a tsc and tcs */ |
| if (gb (pc) == TSC) |
| { |
| while (pc < too_far && gb (pc) != TCS) |
| { |
| pc++; |
| } |
| pc++; |
| /* Skip a stupid inc a */ |
| if (gb (pc) == INCA) |
| pc++; |
| |
| } |
| /* Stack adjust can also be done with n pha's */ |
| while (gb (pc) == PHA) |
| pc++; |
| |
| /* Skip a link - that's a ld/ph/tsc/inc/sta */ |
| |
| if (gb (pc) == LDADIR |
| && gb (pc + 5) == STADIR |
| && gb (pc + 1) == gb (pc + 6) |
| && gb (pc + 2) == PHA |
| && gb (pc + 3) == TSC |
| && gb (pc + 4) == INCA) |
| { |
| pc += 7; |
| } |
| |
| return pc; |
| } |
| |
| |
| register_raw_size (n) |
| { |
| return sim_reg_size (n); |
| } |
| |
| |
| void |
| print_register_hook (regno) |
| { |
| if (regno == P_REGNUM) |
| { |
| /* CCR register */ |
| |
| int C, Z, N, V, I, D, X, M; |
| unsigned char b[1]; |
| unsigned char l; |
| |
| read_relative_register_raw_bytes (regno, b); |
| l = b[0]; |
| printf_unfiltered ("\t"); |
| C = (l & 0x1) != 0; |
| Z = (l & 0x2) != 0; |
| I = (l & 0x4) != 0; |
| D = (l & 0x8) != 0; |
| X = (l & 0x10) != 0; |
| M = (l & 0x20) != 0; |
| V = (l & 0x40) != 0; |
| N = (l & 0x80) != 0; |
| |
| printf_unfiltered ("N-%d ", N); |
| printf_unfiltered ("V-%d ", V); |
| printf_unfiltered ("M-%d ", M); |
| printf_unfiltered ("X-%d ", X); |
| printf_unfiltered ("D-%d ", D); |
| printf_unfiltered ("I-%d ", I); |
| printf_unfiltered ("Z-%d ", Z); |
| printf_unfiltered ("C-%d ", C); |
| if ((C | Z) == 0) |
| printf_unfiltered ("u> "); |
| if ((C | Z) == 1) |
| printf_unfiltered ("u<= "); |
| if ((C == 0)) |
| printf_unfiltered ("u>= "); |
| if (C == 1) |
| printf_unfiltered ("u< "); |
| if (Z == 0) |
| printf_unfiltered ("!= "); |
| if (Z == 1) |
| printf_unfiltered ("== "); |
| if ((N ^ V) == 0) |
| printf_unfiltered (">= "); |
| if ((N ^ V) == 1) |
| printf_unfiltered ("< "); |
| if ((Z | (N ^ V)) == 0) |
| printf_unfiltered ("> "); |
| if ((Z | (N ^ V)) == 1) |
| printf_unfiltered ("<= "); |
| } |
| } |
| |
| void |
| _initialize_w65_tdep () |
| { |
| tm_print_insn = print_insn_w65; |
| } |