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;
37 static gdbarch_register_byte_ftype vax_register_byte;
38 static gdbarch_register_raw_size_ftype vax_register_raw_size;
39 static gdbarch_register_virtual_size_ftype vax_register_virtual_size;
40 static gdbarch_register_virtual_type_ftype vax_register_virtual_type;
42 static gdbarch_skip_prologue_ftype vax_skip_prologue;
43 static gdbarch_frame_num_args_ftype vax_frame_num_args;
44 static gdbarch_deprecated_frame_chain_ftype vax_frame_chain;
45 static gdbarch_frame_args_address_ftype vax_frame_args_address;
46 static gdbarch_frame_locals_address_ftype vax_frame_locals_address;
48 static gdbarch_deprecated_extract_return_value_ftype vax_extract_return_value;
49 static gdbarch_deprecated_extract_struct_value_address_ftype
50 vax_extract_struct_value_address;
52 static gdbarch_deprecated_push_dummy_frame_ftype vax_push_dummy_frame;
55 vax_register_name (int regno)
57 static char *register_names[] =
59 "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
60 "r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc",
66 if (regno >= (sizeof(register_names) / sizeof(*register_names)))
68 return (register_names[regno]);
72 vax_register_byte (int regno)
78 vax_register_raw_size (int regno)
84 vax_register_virtual_size (int regno)
90 vax_register_virtual_type (int regno)
92 return (builtin_type_int);
96 vax_frame_init_saved_regs (struct frame_info *frame)
101 if (get_frame_saved_regs (frame))
104 frame_saved_regs_zalloc (frame);
106 regmask = read_memory_integer (get_frame_base (frame) + 4, 4) >> 16;
108 next_addr = get_frame_base (frame) + 16;
110 /* regmask's low bit is for register 0, which is the first one
111 what would be pushed. */
112 for (regnum = 0; regnum < VAX_AP_REGNUM; regnum++)
114 if (regmask & (1 << regnum))
115 get_frame_saved_regs (frame)[regnum] = next_addr += 4;
118 get_frame_saved_regs (frame)[SP_REGNUM] = next_addr + 4;
119 if (regmask & (1 << DEPRECATED_FP_REGNUM))
120 get_frame_saved_regs (frame)[SP_REGNUM] +=
121 4 + (4 * read_memory_integer (next_addr + 4, 4));
123 get_frame_saved_regs (frame)[PC_REGNUM] = get_frame_base (frame) + 16;
124 get_frame_saved_regs (frame)[DEPRECATED_FP_REGNUM] = get_frame_base (frame) + 12;
125 get_frame_saved_regs (frame)[VAX_AP_REGNUM] = get_frame_base (frame) + 8;
126 get_frame_saved_regs (frame)[PS_REGNUM] = get_frame_base (frame) + 4;
129 /* Get saved user PC for sigtramp from sigcontext for BSD style sigtramp. */
132 vax_sigtramp_saved_pc (struct frame_info *frame)
134 CORE_ADDR sigcontext_addr;
136 int ptrbytes = TYPE_LENGTH (builtin_type_void_func_ptr);
137 int sigcontext_offs = (2 * TARGET_INT_BIT) / TARGET_CHAR_BIT;
139 buf = alloca (ptrbytes);
140 /* Get sigcontext address, it is the third parameter on the stack. */
141 if (get_next_frame (frame))
142 sigcontext_addr = read_memory_typed_address
143 (FRAME_ARGS_ADDRESS (get_next_frame (frame))
144 + FRAME_ARGS_SKIP + sigcontext_offs,
145 builtin_type_void_data_ptr);
147 sigcontext_addr = read_memory_typed_address
148 (read_register (SP_REGNUM) + sigcontext_offs, builtin_type_void_data_ptr);
150 /* Don't cause a memory_error when accessing sigcontext in case the stack
151 layout has changed or the stack is corrupt. */
152 target_read_memory (sigcontext_addr + SIGCONTEXT_PC_OFFSET, buf, ptrbytes);
153 return extract_typed_address (buf, builtin_type_void_func_ptr);
157 vax_frame_saved_pc (struct frame_info *frame)
159 if ((get_frame_type (frame) == SIGTRAMP_FRAME))
160 return (vax_sigtramp_saved_pc (frame)); /* XXXJRT */
162 return (read_memory_integer (get_frame_base (frame) + 16, 4));
166 vax_frame_args_address (struct frame_info *frame)
168 /* In most of GDB, getting the args address is too important to just
169 say "I don't know". This is sometimes wrong for functions that
170 aren't on top of the stack, but c'est la vie. */
171 if (get_next_frame (frame))
172 return (read_memory_integer (get_frame_base (get_next_frame (frame)) + 8, 4));
173 /* Cannot find the AP register value directly from the FP value.
174 Must find it saved in the frame called by this one, or in the AP
175 register for the innermost frame. However, there is no way to
176 tell the difference between the innermost frame and a frame for
177 which we just don't know the frame that it called (e.g. "info
178 frame 0x7ffec789"). For the sake of argument, suppose that the
179 stack is somewhat trashed (which is one reason that "info frame"
180 exists). So, return 0 (indicating we don't know the address of
181 the arglist) if we don't know what frame this frame calls. */
186 vax_frame_locals_address (struct frame_info *frame)
188 return (get_frame_base (frame));
192 vax_frame_num_args (struct frame_info *fi)
194 return (0xff & read_memory_integer (FRAME_ARGS_ADDRESS (fi), 1));
198 vax_frame_chain (struct frame_info *frame)
200 /* In the case of the VAX, the frame's nominal address is the FP value,
201 and 12 bytes later comes the saved previous FP value as a 4-byte word. */
202 if (inside_entry_file (get_frame_pc (frame)))
205 return (read_memory_integer (get_frame_base (frame) + 12, 4));
209 vax_push_dummy_frame (void)
211 CORE_ADDR sp = read_register (SP_REGNUM);
214 sp = push_word (sp, 0); /* arglist */
215 for (regnum = 11; regnum >= 0; regnum--)
216 sp = push_word (sp, read_register (regnum));
217 sp = push_word (sp, read_register (PC_REGNUM));
218 sp = push_word (sp, read_register (DEPRECATED_FP_REGNUM));
219 sp = push_word (sp, read_register (VAX_AP_REGNUM));
220 sp = push_word (sp, (read_register (PS_REGNUM) & 0xffef) + 0x2fff0000);
221 sp = push_word (sp, 0);
222 write_register (SP_REGNUM, sp);
223 write_register (DEPRECATED_FP_REGNUM, sp);
224 write_register (VAX_AP_REGNUM, sp + (17 * 4));
230 CORE_ADDR fp = read_register (DEPRECATED_FP_REGNUM);
232 int regmask = read_memory_integer (fp + 4, 4);
234 write_register (PS_REGNUM,
236 | (read_register (PS_REGNUM) & 0xffff0000));
237 write_register (PC_REGNUM, read_memory_integer (fp + 16, 4));
238 write_register (DEPRECATED_FP_REGNUM, read_memory_integer (fp + 12, 4));
239 write_register (VAX_AP_REGNUM, read_memory_integer (fp + 8, 4));
241 for (regnum = 0; regnum < 12; regnum++)
242 if (regmask & (0x10000 << regnum))
243 write_register (regnum, read_memory_integer (fp += 4, 4));
244 fp = fp + 4 + ((regmask >> 30) & 3);
245 if (regmask & 0x20000000)
247 regnum = read_memory_integer (fp, 4);
248 fp += (regnum + 1) * 4;
250 write_register (SP_REGNUM, fp);
251 flush_cached_frames ();
254 /* The VAX call dummy sequence:
256 calls #69, @#32323232
259 It is 8 bytes long. The address and argc are patched by
260 vax_fix_call_dummy(). */
261 static LONGEST vax_call_dummy_words[] = { 0x329f69fb, 0x03323232 };
262 static int sizeof_vax_call_dummy_words = sizeof(vax_call_dummy_words);
265 vax_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
266 struct value **args, struct type *type, int gcc_p)
269 store_unsigned_integer (dummy + 3, 4, fun);
273 vax_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
275 write_register (1, addr);
279 vax_extract_return_value (struct type *valtype, char *regbuf, char *valbuf)
281 memcpy (valbuf, regbuf + REGISTER_BYTE (0), TYPE_LENGTH (valtype));
285 vax_store_return_value (struct type *valtype, char *valbuf)
287 deprecated_write_register_bytes (0, valbuf, TYPE_LENGTH (valtype));
291 vax_extract_struct_value_address (char *regbuf)
293 return (extract_unsigned_integer (regbuf + REGISTER_BYTE (0),
294 REGISTER_RAW_SIZE (0)));
297 static const unsigned char *
298 vax_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
300 static const unsigned char vax_breakpoint[] = { 3 };
302 *lenptr = sizeof(vax_breakpoint);
303 return (vax_breakpoint);
306 /* Advance PC across any function entry prologue instructions
307 to reach some "real" code. */
310 vax_skip_prologue (CORE_ADDR pc)
312 register int op = (unsigned char) read_memory_integer (pc, 1);
314 pc += 2; /* skip brb */
316 pc += 3; /* skip brw */
318 && ((unsigned char) read_memory_integer (pc + 2, 1)) == 0x5E)
319 pc += 3; /* skip subl2 */
321 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xAE
322 && ((unsigned char) read_memory_integer (pc + 3, 1)) == 0x5E)
323 pc += 4; /* skip movab */
325 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xCE
326 && ((unsigned char) read_memory_integer (pc + 4, 1)) == 0x5E)
327 pc += 5; /* skip movab */
329 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xEE
330 && ((unsigned char) read_memory_integer (pc + 6, 1)) == 0x5E)
331 pc += 7; /* skip movab */
336 vax_saved_pc_after_call (struct frame_info *frame)
338 return (DEPRECATED_FRAME_SAVED_PC(frame));
341 /* Initialize the current architecture based on INFO. If possible, re-use an
342 architecture from ARCHES, which is a list of architectures already created
343 during this debugging session.
345 Called e.g. at program startup, when reading a core file, and when reading
348 static struct gdbarch *
349 vax_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
351 struct gdbarch *gdbarch;
353 /* If there is already a candidate, use it. */
354 arches = gdbarch_list_lookup_by_info (arches, &info);
356 return arches->gdbarch;
358 gdbarch = gdbarch_alloc (&info, NULL);
360 /* NOTE: cagney/2002-12-06: This can be deleted when this arch is
361 ready to unwind the PC first (see frame.c:get_prev_frame()). */
362 set_gdbarch_deprecated_init_frame_pc (gdbarch, init_frame_pc_default);
365 set_gdbarch_num_regs (gdbarch, VAX_NUM_REGS);
366 set_gdbarch_sp_regnum (gdbarch, VAX_SP_REGNUM);
367 set_gdbarch_deprecated_fp_regnum (gdbarch, VAX_FP_REGNUM);
368 set_gdbarch_pc_regnum (gdbarch, VAX_PC_REGNUM);
369 set_gdbarch_ps_regnum (gdbarch, VAX_PS_REGNUM);
371 set_gdbarch_register_name (gdbarch, vax_register_name);
372 set_gdbarch_deprecated_register_size (gdbarch, VAX_REGISTER_SIZE);
373 set_gdbarch_deprecated_register_bytes (gdbarch, VAX_REGISTER_BYTES);
374 set_gdbarch_register_byte (gdbarch, vax_register_byte);
375 set_gdbarch_register_raw_size (gdbarch, vax_register_raw_size);
376 set_gdbarch_deprecated_max_register_raw_size (gdbarch, VAX_MAX_REGISTER_RAW_SIZE);
377 set_gdbarch_register_virtual_size (gdbarch, vax_register_virtual_size);
378 set_gdbarch_deprecated_max_register_virtual_size (gdbarch,
379 VAX_MAX_REGISTER_VIRTUAL_SIZE);
380 set_gdbarch_register_virtual_type (gdbarch, vax_register_virtual_type);
382 /* Frame and stack info */
383 set_gdbarch_skip_prologue (gdbarch, vax_skip_prologue);
384 set_gdbarch_deprecated_saved_pc_after_call (gdbarch, vax_saved_pc_after_call);
386 set_gdbarch_frame_num_args (gdbarch, vax_frame_num_args);
387 set_gdbarch_frameless_function_invocation (gdbarch,
388 generic_frameless_function_invocation_not);
390 set_gdbarch_deprecated_frame_chain (gdbarch, vax_frame_chain);
391 set_gdbarch_deprecated_frame_saved_pc (gdbarch, vax_frame_saved_pc);
393 set_gdbarch_frame_args_address (gdbarch, vax_frame_args_address);
394 set_gdbarch_frame_locals_address (gdbarch, vax_frame_locals_address);
396 set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, vax_frame_init_saved_regs);
398 set_gdbarch_frame_args_skip (gdbarch, 4);
400 set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
402 /* Return value info */
403 set_gdbarch_deprecated_store_struct_return (gdbarch, vax_store_struct_return);
404 set_gdbarch_deprecated_extract_return_value (gdbarch, vax_extract_return_value);
405 set_gdbarch_deprecated_store_return_value (gdbarch, vax_store_return_value);
406 set_gdbarch_deprecated_extract_struct_value_address (gdbarch, vax_extract_struct_value_address);
408 /* Call dummy info */
409 set_gdbarch_deprecated_push_dummy_frame (gdbarch, vax_push_dummy_frame);
410 set_gdbarch_deprecated_pop_frame (gdbarch, vax_pop_frame);
411 set_gdbarch_call_dummy_location (gdbarch, ON_STACK);
412 set_gdbarch_deprecated_call_dummy_words (gdbarch, vax_call_dummy_words);
413 set_gdbarch_deprecated_sizeof_call_dummy_words (gdbarch, sizeof_vax_call_dummy_words);
414 set_gdbarch_deprecated_fix_call_dummy (gdbarch, vax_fix_call_dummy);
415 set_gdbarch_deprecated_call_dummy_breakpoint_offset (gdbarch, 7);
416 set_gdbarch_deprecated_use_generic_dummy_frames (gdbarch, 0);
417 set_gdbarch_deprecated_pc_in_call_dummy (gdbarch, deprecated_pc_in_call_dummy_on_stack);
419 /* Breakpoint info */
420 set_gdbarch_breakpoint_from_pc (gdbarch, vax_breakpoint_from_pc);
421 set_gdbarch_decr_pc_after_break (gdbarch, 0);
424 set_gdbarch_function_start_offset (gdbarch, 2);
425 set_gdbarch_believe_pcc_promotion (gdbarch, 1);
427 /* Should be using push_dummy_call. */
428 set_gdbarch_deprecated_dummy_write_sp (gdbarch, deprecated_write_sp);
430 /* Hook in ABI-specific overrides, if they have been registered. */
431 gdbarch_init_osabi (info, gdbarch);
433 set_gdbarch_print_insn (gdbarch, print_insn_vax);
439 _initialize_vax_tdep (void)
441 gdbarch_register (bfd_arch_vax, vax_gdbarch_init, NULL);