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_correct (struct frame_info *frame)
168 if (get_next_frame (frame))
169 return (read_memory_integer (get_frame_base (get_next_frame (frame)) + 8, 4));
175 vax_frame_args_address (struct frame_info *frame)
177 /* In most of GDB, getting the args address is too important to just
178 say "I don't know". This is sometimes wrong for functions that
179 aren't on top of the stack, but c'est la vie. */
180 if (get_next_frame (frame))
181 return (read_memory_integer (get_frame_base (get_next_frame (frame)) + 8, 4));
182 /* Cannot find the AP register value directly from the FP value.
183 Must find it saved in the frame called by this one, or in the AP
184 register for the innermost frame. However, there is no way to
185 tell the difference between the innermost frame and a frame for
186 which we just don't know the frame that it called (e.g. "info
187 frame 0x7ffec789"). For the sake of argument, suppose that the
188 stack is somewhat trashed (which is one reason that "info frame"
189 exists). So, return 0 (indicating we don't know the address of
190 the arglist) if we don't know what frame this frame calls. */
195 vax_frame_locals_address (struct frame_info *frame)
197 return (get_frame_base (frame));
201 vax_frame_num_args (struct frame_info *fi)
203 return (0xff & read_memory_integer (FRAME_ARGS_ADDRESS (fi), 1));
207 vax_frame_chain (struct frame_info *frame)
209 /* In the case of the VAX, the frame's nominal address is the FP value,
210 and 12 bytes later comes the saved previous FP value as a 4-byte word. */
211 if (inside_entry_file (get_frame_pc (frame)))
214 return (read_memory_integer (get_frame_base (frame) + 12, 4));
218 vax_push_dummy_frame (void)
220 CORE_ADDR sp = read_register (SP_REGNUM);
223 sp = push_word (sp, 0); /* arglist */
224 for (regnum = 11; regnum >= 0; regnum--)
225 sp = push_word (sp, read_register (regnum));
226 sp = push_word (sp, read_register (PC_REGNUM));
227 sp = push_word (sp, read_register (DEPRECATED_FP_REGNUM));
228 sp = push_word (sp, read_register (VAX_AP_REGNUM));
229 sp = push_word (sp, (read_register (PS_REGNUM) & 0xffef) + 0x2fff0000);
230 sp = push_word (sp, 0);
231 write_register (SP_REGNUM, sp);
232 write_register (DEPRECATED_FP_REGNUM, sp);
233 write_register (VAX_AP_REGNUM, sp + (17 * 4));
239 CORE_ADDR fp = read_register (DEPRECATED_FP_REGNUM);
241 int regmask = read_memory_integer (fp + 4, 4);
243 write_register (PS_REGNUM,
245 | (read_register (PS_REGNUM) & 0xffff0000));
246 write_register (PC_REGNUM, read_memory_integer (fp + 16, 4));
247 write_register (DEPRECATED_FP_REGNUM, read_memory_integer (fp + 12, 4));
248 write_register (VAX_AP_REGNUM, read_memory_integer (fp + 8, 4));
250 for (regnum = 0; regnum < 12; regnum++)
251 if (regmask & (0x10000 << regnum))
252 write_register (regnum, read_memory_integer (fp += 4, 4));
253 fp = fp + 4 + ((regmask >> 30) & 3);
254 if (regmask & 0x20000000)
256 regnum = read_memory_integer (fp, 4);
257 fp += (regnum + 1) * 4;
259 write_register (SP_REGNUM, fp);
260 flush_cached_frames ();
263 /* The VAX call dummy sequence:
265 calls #69, @#32323232
268 It is 8 bytes long. The address and argc are patched by
269 vax_fix_call_dummy(). */
270 static LONGEST vax_call_dummy_words[] = { 0x329f69fb, 0x03323232 };
271 static int sizeof_vax_call_dummy_words = sizeof(vax_call_dummy_words);
274 vax_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
275 struct value **args, struct type *type, int gcc_p)
278 store_unsigned_integer (dummy + 3, 4, fun);
282 vax_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
284 write_register (1, addr);
288 vax_extract_return_value (struct type *valtype, char *regbuf, char *valbuf)
290 memcpy (valbuf, regbuf + REGISTER_BYTE (0), TYPE_LENGTH (valtype));
294 vax_store_return_value (struct type *valtype, char *valbuf)
296 deprecated_write_register_bytes (0, valbuf, TYPE_LENGTH (valtype));
300 vax_extract_struct_value_address (char *regbuf)
302 return (extract_unsigned_integer (regbuf + REGISTER_BYTE (0),
303 REGISTER_RAW_SIZE (0)));
306 static const unsigned char *
307 vax_breakpoint_from_pc (CORE_ADDR *pcptr, int *lenptr)
309 static const unsigned char vax_breakpoint[] = { 3 };
311 *lenptr = sizeof(vax_breakpoint);
312 return (vax_breakpoint);
315 /* Advance PC across any function entry prologue instructions
316 to reach some "real" code. */
319 vax_skip_prologue (CORE_ADDR pc)
321 register int op = (unsigned char) read_memory_integer (pc, 1);
323 pc += 2; /* skip brb */
325 pc += 3; /* skip brw */
327 && ((unsigned char) read_memory_integer (pc + 2, 1)) == 0x5E)
328 pc += 3; /* skip subl2 */
330 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xAE
331 && ((unsigned char) read_memory_integer (pc + 3, 1)) == 0x5E)
332 pc += 4; /* skip movab */
334 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xCE
335 && ((unsigned char) read_memory_integer (pc + 4, 1)) == 0x5E)
336 pc += 5; /* skip movab */
338 && ((unsigned char) read_memory_integer (pc + 1, 1)) == 0xEE
339 && ((unsigned char) read_memory_integer (pc + 6, 1)) == 0x5E)
340 pc += 7; /* skip movab */
345 vax_saved_pc_after_call (struct frame_info *frame)
347 return (DEPRECATED_FRAME_SAVED_PC(frame));
350 /* Initialize the current architecture based on INFO. If possible, re-use an
351 architecture from ARCHES, which is a list of architectures already created
352 during this debugging session.
354 Called e.g. at program startup, when reading a core file, and when reading
357 static struct gdbarch *
358 vax_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
360 struct gdbarch *gdbarch;
362 /* If there is already a candidate, use it. */
363 arches = gdbarch_list_lookup_by_info (arches, &info);
365 return arches->gdbarch;
367 gdbarch = gdbarch_alloc (&info, NULL);
369 /* NOTE: cagney/2002-12-06: This can be deleted when this arch is
370 ready to unwind the PC first (see frame.c:get_prev_frame()). */
371 set_gdbarch_deprecated_init_frame_pc (gdbarch, init_frame_pc_default);
374 set_gdbarch_num_regs (gdbarch, VAX_NUM_REGS);
375 set_gdbarch_sp_regnum (gdbarch, VAX_SP_REGNUM);
376 set_gdbarch_deprecated_fp_regnum (gdbarch, VAX_FP_REGNUM);
377 set_gdbarch_pc_regnum (gdbarch, VAX_PC_REGNUM);
378 set_gdbarch_ps_regnum (gdbarch, VAX_PS_REGNUM);
380 set_gdbarch_register_name (gdbarch, vax_register_name);
381 set_gdbarch_deprecated_register_size (gdbarch, VAX_REGISTER_SIZE);
382 set_gdbarch_deprecated_register_bytes (gdbarch, VAX_REGISTER_BYTES);
383 set_gdbarch_register_byte (gdbarch, vax_register_byte);
384 set_gdbarch_register_raw_size (gdbarch, vax_register_raw_size);
385 set_gdbarch_deprecated_max_register_raw_size (gdbarch, VAX_MAX_REGISTER_RAW_SIZE);
386 set_gdbarch_register_virtual_size (gdbarch, vax_register_virtual_size);
387 set_gdbarch_deprecated_max_register_virtual_size (gdbarch,
388 VAX_MAX_REGISTER_VIRTUAL_SIZE);
389 set_gdbarch_register_virtual_type (gdbarch, vax_register_virtual_type);
391 /* Frame and stack info */
392 set_gdbarch_skip_prologue (gdbarch, vax_skip_prologue);
393 set_gdbarch_deprecated_saved_pc_after_call (gdbarch, vax_saved_pc_after_call);
395 set_gdbarch_frame_num_args (gdbarch, vax_frame_num_args);
396 set_gdbarch_frameless_function_invocation (gdbarch,
397 generic_frameless_function_invocation_not);
399 set_gdbarch_deprecated_frame_chain (gdbarch, vax_frame_chain);
400 set_gdbarch_deprecated_frame_saved_pc (gdbarch, vax_frame_saved_pc);
402 set_gdbarch_frame_args_address (gdbarch, vax_frame_args_address);
403 set_gdbarch_frame_locals_address (gdbarch, vax_frame_locals_address);
405 set_gdbarch_deprecated_frame_init_saved_regs (gdbarch, vax_frame_init_saved_regs);
407 set_gdbarch_frame_args_skip (gdbarch, 4);
409 set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
411 /* Return value info */
412 set_gdbarch_deprecated_store_struct_return (gdbarch, vax_store_struct_return);
413 set_gdbarch_deprecated_extract_return_value (gdbarch, vax_extract_return_value);
414 set_gdbarch_deprecated_store_return_value (gdbarch, vax_store_return_value);
415 set_gdbarch_deprecated_extract_struct_value_address (gdbarch, vax_extract_struct_value_address);
417 /* Call dummy info */
418 set_gdbarch_deprecated_push_dummy_frame (gdbarch, vax_push_dummy_frame);
419 set_gdbarch_deprecated_pop_frame (gdbarch, vax_pop_frame);
420 set_gdbarch_call_dummy_location (gdbarch, ON_STACK);
421 set_gdbarch_deprecated_call_dummy_words (gdbarch, vax_call_dummy_words);
422 set_gdbarch_deprecated_sizeof_call_dummy_words (gdbarch, sizeof_vax_call_dummy_words);
423 set_gdbarch_deprecated_fix_call_dummy (gdbarch, vax_fix_call_dummy);
424 set_gdbarch_deprecated_call_dummy_breakpoint_offset (gdbarch, 7);
425 set_gdbarch_deprecated_use_generic_dummy_frames (gdbarch, 0);
426 set_gdbarch_deprecated_pc_in_call_dummy (gdbarch, deprecated_pc_in_call_dummy_on_stack);
428 /* Breakpoint info */
429 set_gdbarch_breakpoint_from_pc (gdbarch, vax_breakpoint_from_pc);
430 set_gdbarch_decr_pc_after_break (gdbarch, 0);
433 set_gdbarch_function_start_offset (gdbarch, 2);
434 set_gdbarch_believe_pcc_promotion (gdbarch, 1);
436 /* Should be using push_dummy_call. */
437 set_gdbarch_deprecated_dummy_write_sp (gdbarch, deprecated_write_sp);
439 /* Hook in ABI-specific overrides, if they have been registered. */
440 gdbarch_init_osabi (info, gdbarch);
442 set_gdbarch_print_insn (gdbarch, print_insn_vax);
448 _initialize_vax_tdep (void)
450 gdbarch_register (bfd_arch_vax, vax_gdbarch_init, NULL);