1 /* Print VAX instructions for GDB, the GNU debugger.
2 Copyright 1986, 1989, 1991, 1992, 1995, 1996, 1998, 1999, 2000, 2002, 2003
3 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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. */
24 #include "opcode/vax.h"
30 #include "arch-utils.h"
31 #include "gdb_string.h"
36 static gdbarch_register_name_ftype vax_register_name;
38 static gdbarch_skip_prologue_ftype vax_skip_prologue;
39 static gdbarch_frame_num_args_ftype vax_frame_num_args;
40 static gdbarch_deprecated_frame_chain_ftype vax_frame_chain;
42 static gdbarch_deprecated_extract_return_value_ftype vax_extract_return_value;
43 static gdbarch_deprecated_extract_struct_value_address_ftype
44 vax_extract_struct_value_address;
46 static gdbarch_deprecated_push_dummy_frame_ftype vax_push_dummy_frame;
49 vax_register_name (int regno)
51 static char *register_names[] =
53 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
54 "r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc",
60 if (regno >= (sizeof(register_names) / sizeof(*register_names)))
62 return (register_names[regno]);
66 vax_register_byte (int regno)
72 vax_register_raw_size (int regno)
78 vax_register_virtual_size (int regno)
84 vax_register_virtual_type (int regno)
86 return (builtin_type_int);
90 vax_frame_init_saved_regs (struct frame_info *frame)
95 if (get_frame_saved_regs (frame))
98 frame_saved_regs_zalloc (frame);
100 regmask = read_memory_integer (get_frame_base (frame) + 4, 4) >> 16;
102 next_addr = get_frame_base (frame) + 16;
104 /* regmask's low bit is for register 0, which is the first one
105 what would be pushed. */
106 for (regnum = 0; regnum < VAX_AP_REGNUM; regnum++)
108 if (regmask & (1 << regnum))
109 get_frame_saved_regs (frame)[regnum] = next_addr += 4;
112 get_frame_saved_regs (frame)[SP_REGNUM] = next_addr + 4;
113 if (regmask & (1 << DEPRECATED_FP_REGNUM))
114 get_frame_saved_regs (frame)[SP_REGNUM] +=
115 4 + (4 * read_memory_integer (next_addr + 4, 4));
117 get_frame_saved_regs (frame)[PC_REGNUM] = get_frame_base (frame) + 16;
118 get_frame_saved_regs (frame)[DEPRECATED_FP_REGNUM] = get_frame_base (frame) + 12;
119 get_frame_saved_regs (frame)[VAX_AP_REGNUM] = get_frame_base (frame) + 8;
120 get_frame_saved_regs (frame)[PS_REGNUM] = get_frame_base (frame) + 4;
123 /* Get saved user PC for sigtramp from sigcontext for BSD style sigtramp. */
126 vax_sigtramp_saved_pc (struct frame_info *frame)
128 CORE_ADDR sigcontext_addr;
130 int ptrbytes = TYPE_LENGTH (builtin_type_void_func_ptr);
131 int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT;
133 buf = alloca (ptrbytes);
134 /* Get sigcontext address, it is the third parameter on the stack. */
135 if (get_next_frame (frame))
136 sigcontext_addr = read_memory_typed_address
137 (DEPRECATED_FRAME_ARGS_ADDRESS (get_next_frame (frame))
138 + FRAME_ARGS_SKIP + sigcontext_offs,
139 builtin_type_void_data_ptr);
141 sigcontext_addr = read_memory_typed_address
142 (read_register (SP_REGNUM) + sigcontext_offs, builtin_type_void_data_ptr);
144 /* Don't cause a memory_error when accessing sigcontext in case the stack
145 layout has changed or the stack is corrupt. */
146 target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, ptrbytes);
147 return extract_typed_address (buf, builtin_type_void_func_ptr);
151 vax_frame_saved_pc (struct frame_info *frame)
153 if ((get_frame_type (frame) == SIGTRAMP_FRAME))
154 return (vax_sigtramp_saved_pc (frame)); /* XXXJRT */
156 return (read_memory_integer (get_frame_base (frame) + 16, 4));
160 vax_frame_args_address (struct frame_info *frame)
162 /* In most of GDB, getting the args address is too important to just
163 say "I don't know". This is sometimes wrong for functions that
164 aren't on top of the stack, but c'est la vie. */
165 if (get_next_frame (frame))
166 return (read_memory_integer (get_frame_base (get_next_frame (frame)) + 8, 4));
167 /* Cannot find the AP register value directly from the FP value.
168 Must find it saved in the frame called by this one, or in the AP
169 register for the innermost frame. However, there is no way to
170 tell the difference between the innermost frame and a frame for
171 which we just don't know the frame that it called (e.g. "info
172 frame 0x7ffec789"). For the sake of argument, suppose that the
173 stack is somewhat trashed (which is one reason that "info frame"
174 exists). So, return 0 (indicating we don't know the address of
175 the arglist) if we don't know what frame this frame calls. */
180 vax_frame_num_args (struct frame_info *fi)
182 return (0xff & read_memory_integer (DEPRECATED_FRAME_ARGS_ADDRESS (fi), 1));
186 vax_frame_chain (struct frame_info *frame)
188 /* In the case of the VAX, the frame's nominal address is the FP value,
189 and 12 bytes later comes the saved previous FP value as a 4-byte word. */
190 if (inside_entry_file (get_frame_pc (frame)))
193 return (read_memory_integer (get_frame_base (frame) + 12, 4));
197 vax_push_dummy_frame (void)
199 CORE_ADDR sp = read_register (SP_REGNUM);
202 sp = push_word (sp, 0); /* arglist */
203 for (regnum = 11; regnum >= 0; regnum--)
204 sp = push_word (sp, read_register (regnum));
205 sp = push_word (sp, read_register (PC_REGNUM));
206 sp = push_word (sp, read_register (DEPRECATED_FP_REGNUM));
207 sp = push_word (sp, read_register (VAX_AP_REGNUM));
208 sp = push_word (sp, (read_register (PS_REGNUM) & 0xffef) + 0x2fff0000);
209 sp = push_word (sp, 0);
210 write_register (SP_REGNUM, sp);
211 write_register (DEPRECATED_FP_REGNUM, sp);
212 write_register (VAX_AP_REGNUM, sp + (17 * 4));
218 CORE_ADDR fp = read_register (DEPRECATED_FP_REGNUM);
220 int regmask = read_memory_integer (fp + 4, 4);
222 write_register (PS_REGNUM,
224 | (read_register (PS_REGNUM) & 0xffff0000));
225 write_register (PC_REGNUM, read_memory_integer (fp + 16, 4));
226 write_register (DEPRECATED_FP_REGNUM, read_memory_integer (fp + 12, 4));
227 write_register (VAX_AP_REGNUM, read_memory_integer (fp + 8, 4));
229 for (regnum = 0; regnum < 12; regnum++)
230 if (regmask & (0x10000 << regnum))
231 write_register (regnum, read_memory_integer (fp += 4, 4));
232 fp = fp + 4 + ((regmask >> 30) & 3);
233 if (regmask & 0x20000000)
235 regnum = read_memory_integer (fp, 4);
236 fp += (regnum + 1) * 4;
238 write_register (SP_REGNUM, fp);
239 flush_cached_frames ();
242 /* The VAX call dummy sequence:
244 calls #69, @#32323232
247 It is 8 bytes long. The address and argc are patched by
248 vax_fix_call_dummy(). */
249 static LONGEST vax_call_dummy_words[] = { 0x329f69fb, 0x03323232 };
250 static int sizeof_vax_call_dummy_words = sizeof(vax_call_dummy_words);
253 vax_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
254 struct value **args, struct type *type, int gcc_p)
257 store_unsigned_integer (dummy + 3, 4, fun);
261 vax_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
263 write_register (1, addr);
267 vax_extract_return_value (struct type *valtype, char *regbuf, char *valbuf)
269 memcpy (valbuf, regbuf + REGISTER_BYTE (0), TYPE_LENGTH (valtype));
273 vax_store_return_value (struct type *valtype, char *valbuf)
275 deprecated_write_register_bytes (0, valbuf, TYPE_LENGTH (valtype));
279 vax_extract_struct_value_address (char *regbuf)
281 return (extract_unsigned_integer (regbuf + REGISTER_BYTE (0),
282 REGISTER_RAW_SIZE (0)));
285 static const unsigned char *
286 vax_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
288 static const unsigned char vax_breakpoint[] = { 3 };
290 *lenptr = sizeof(vax_breakpoint);
291 return (vax_breakpoint);
294 /* Advance PC across any function entry prologue instructions
295 to reach some "real" code. */
298 vax_skip_prologue (CORE_ADDR pc)
300 register int op = (unsigned char) read_memory_integer (pc, 1);
302 pc += 2; /* skip brb */
304 pc += 3; /* skip brw */
306 && ((unsigned char) read_memory_integer (pc + 2, 1)) == 0x5E)
307 pc += 3; /* skip subl2 */
309 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xAE
310 && ((unsigned char) read_memory_integer (pc + 3, 1)) == 0x5E)
311 pc += 4; /* skip movab */
313 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xCE
314 && ((unsigned char) read_memory_integer (pc + 4, 1)) == 0x5E)
315 pc += 5; /* skip movab */
317 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xEE
318 && ((unsigned char) read_memory_integer (pc + 6, 1)) == 0x5E)
319 pc += 7; /* skip movab */
324 vax_saved_pc_after_call (struct frame_info *frame)
326 return (DEPRECATED_FRAME_SAVED_PC(frame));
329 /* Initialize the current architecture based on INFO. If possible, re-use an
330 architecture from ARCHES, which is a list of architectures already created
331 during this debugging session.
333 Called e.g. at program startup, when reading a core file, and when reading
336 static struct gdbarch *
337 vax_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
339 struct gdbarch *gdbarch;
341 /* If there is already a candidate, use it. */
342 arches = gdbarch_list_lookup_by_info (arches, &info);
344 return arches->gdbarch;
346 gdbarch = gdbarch_alloc (&info, NULL);
348 /* NOTE: cagney/2002-12-06: This can be deleted when this arch is
349 ready to unwind the PC first (see frame.c:get_prev_frame()). */
350 set_gdbarch_deprecated_init_frame_pc (gdbarch, init_frame_pc_default);
353 set_gdbarch_num_regs (gdbarch, VAX_NUM_REGS);
354 set_gdbarch_sp_regnum (gdbarch, VAX_SP_REGNUM);
355 set_gdbarch_deprecated_fp_regnum (gdbarch, VAX_FP_REGNUM);
356 set_gdbarch_pc_regnum (gdbarch, VAX_PC_REGNUM);
357 set_gdbarch_ps_regnum (gdbarch, VAX_PS_REGNUM);
359 set_gdbarch_register_name (gdbarch, vax_register_name);
360 set_gdbarch_deprecated_register_size (gdbarch, VAX_REGISTER_SIZE);
361 set_gdbarch_deprecated_register_bytes (gdbarch, VAX_REGISTER_BYTES);
362 set_gdbarch_deprecated_register_byte (gdbarch, vax_register_byte);
363 set_gdbarch_deprecated_register_raw_size (gdbarch, vax_register_raw_size);
364 set_gdbarch_deprecated_max_register_raw_size (gdbarch, VAX_MAX_REGISTER_RAW_SIZE);
365 set_gdbarch_deprecated_register_virtual_size (gdbarch, vax_register_virtual_size);
366 set_gdbarch_deprecated_max_register_virtual_size (gdbarch,
367 VAX_MAX_REGISTER_VIRTUAL_SIZE);
368 set_gdbarch_deprecated_register_virtual_type (gdbarch, vax_register_virtual_type);
370 /* Frame and stack info */
371 set_gdbarch_skip_prologue (gdbarch, vax_skip_prologue);
372 set_gdbarch_deprecated_saved_pc_after_call (gdbarch, vax_saved_pc_after_call);
374 set_gdbarch_frame_num_args (gdbarch, vax_frame_num_args);
375 set_gdbarch_frameless_function_invocation (gdbarch,
376 generic_frameless_function_invocation_not);
378 set_gdbarch_deprecated_frame_chain (gdbarch, vax_frame_chain);
379 set_gdbarch_deprecated_frame_saved_pc (gdbarch, vax_frame_saved_pc);
381 set_gdbarch_deprecated_frame_args_address (gdbarch, vax_frame_args_address);
383 set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, vax_frame_init_saved_regs);
385 set_gdbarch_frame_args_skip (gdbarch, 4);
387 set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
389 /* Return value info */
390 set_gdbarch_deprecated_store_struct_return (gdbarch, vax_store_struct_return);
391 set_gdbarch_deprecated_extract_return_value (gdbarch, vax_extract_return_value);
392 set_gdbarch_deprecated_store_return_value (gdbarch, vax_store_return_value);
393 set_gdbarch_deprecated_extract_struct_value_address (gdbarch, vax_extract_struct_value_address);
395 /* Call dummy info */
396 set_gdbarch_deprecated_push_dummy_frame (gdbarch, vax_push_dummy_frame);
397 set_gdbarch_deprecated_pop_frame (gdbarch, vax_pop_frame);
398 set_gdbarch_call_dummy_location (gdbarch, ON_STACK);
399 set_gdbarch_deprecated_call_dummy_words (gdbarch, vax_call_dummy_words);
400 set_gdbarch_deprecated_sizeof_call_dummy_words (gdbarch, sizeof_vax_call_dummy_words);
401 set_gdbarch_deprecated_fix_call_dummy (gdbarch, vax_fix_call_dummy);
402 set_gdbarch_deprecated_call_dummy_breakpoint_offset (gdbarch, 7);
403 set_gdbarch_deprecated_use_generic_dummy_frames (gdbarch, 0);
404 set_gdbarch_deprecated_pc_in_call_dummy (gdbarch, deprecated_pc_in_call_dummy_on_stack);
406 /* Breakpoint info */
407 set_gdbarch_breakpoint_from_pc (gdbarch, vax_breakpoint_from_pc);
408 set_gdbarch_decr_pc_after_break (gdbarch, 0);
411 set_gdbarch_function_start_offset (gdbarch, 2);
412 set_gdbarch_believe_pcc_promotion (gdbarch, 1);
414 /* Should be using push_dummy_call. */
415 set_gdbarch_deprecated_dummy_write_sp (gdbarch, deprecated_write_sp);
417 /* Hook in ABI-specific overrides, if they have been registered. */
418 gdbarch_init_osabi (info, gdbarch);
420 set_gdbarch_print_insn (gdbarch, print_insn_vax);
425 extern initialize_file_ftype _initialize_vax_tdep; /* -Wmissing-prototypes */
428 _initialize_vax_tdep (void)
430 gdbarch_register (bfd_arch_vax, vax_gdbarch_init, NULL);