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 /* Cannot find the AP register value directly from the FP value. Must
169 find it saved in the frame called by this one, or in the AP register
170 for the innermost frame. However, there is no way to tell the
171 difference between the innermost frame and a frame for which we
172 just don't know the frame that it called (e.g. "info frame 0x7ffec789").
173 For the sake of argument, suppose that the stack is somewhat trashed
174 (which is one reason that "info frame" exists). So, return 0 (indicating
175 we don't know the address of the arglist) if we don't know what frame
177 if (get_next_frame (frame))
178 return (read_memory_integer (get_frame_base (get_next_frame (frame)) + 8, 4));
184 vax_frame_args_address (struct frame_info *frame)
186 /* In most of GDB, getting the args address is too important to
187 just say "I don't know". This is sometimes wrong for functions
188 that aren't on top of the stack, but c'est la vie. */
189 if (get_next_frame (frame))
190 return (read_memory_integer (get_frame_base (get_next_frame (frame)) + 8, 4));
192 return (read_register (VAX_AP_REGNUM));
196 vax_frame_locals_address (struct frame_info *frame)
198 return (get_frame_base (frame));
202 vax_frame_num_args (struct frame_info *fi)
204 return (0xff & read_memory_integer (FRAME_ARGS_ADDRESS (fi), 1));
208 vax_frame_chain (struct frame_info *frame)
210 /* In the case of the VAX, the frame's nominal address is the FP value,
211 and 12 bytes later comes the saved previous FP value as a 4-byte word. */
212 if (inside_entry_file (get_frame_pc (frame)))
215 return (read_memory_integer (get_frame_base (frame) + 12, 4));
219 vax_push_dummy_frame (void)
221 CORE_ADDR sp = read_register (SP_REGNUM);
224 sp = push_word (sp, 0); /* arglist */
225 for (regnum = 11; regnum >= 0; regnum--)
226 sp = push_word (sp, read_register (regnum));
227 sp = push_word (sp, read_register (PC_REGNUM));
228 sp = push_word (sp, read_register (DEPRECATED_FP_REGNUM));
229 sp = push_word (sp, read_register (VAX_AP_REGNUM));
230 sp = push_word (sp, (read_register (PS_REGNUM) & 0xffef) + 0x2fff0000);
231 sp = push_word (sp, 0);
232 write_register (SP_REGNUM, sp);
233 write_register (DEPRECATED_FP_REGNUM, sp);
234 write_register (VAX_AP_REGNUM, sp + (17 * 4));
240 CORE_ADDR fp = read_register (DEPRECATED_FP_REGNUM);
242 int regmask = read_memory_integer (fp + 4, 4);
244 write_register (PS_REGNUM,
246 | (read_register (PS_REGNUM) & 0xffff0000));
247 write_register (PC_REGNUM, read_memory_integer (fp + 16, 4));
248 write_register (DEPRECATED_FP_REGNUM, read_memory_integer (fp + 12, 4));
249 write_register (VAX_AP_REGNUM, read_memory_integer (fp + 8, 4));
251 for (regnum = 0; regnum < 12; regnum++)
252 if (regmask & (0x10000 << regnum))
253 write_register (regnum, read_memory_integer (fp += 4, 4));
254 fp = fp + 4 + ((regmask >> 30) & 3);
255 if (regmask & 0x20000000)
257 regnum = read_memory_integer (fp, 4);
258 fp += (regnum + 1) * 4;
260 write_register (SP_REGNUM, fp);
261 flush_cached_frames ();
264 /* The VAX call dummy sequence:
266 calls #69, @#32323232
269 It is 8 bytes long. The address and argc are patched by
270 vax_fix_call_dummy(). */
271 static LONGEST vax_call_dummy_words[] = { 0x329f69fb, 0x03323232 };
272 static int sizeof_vax_call_dummy_words = sizeof(vax_call_dummy_words);
275 vax_fix_call_dummy (char *dummy, CORE_ADDR pc, CORE_ADDR fun, int nargs,
276 struct value **args, struct type *type, int gcc_p)
279 store_unsigned_integer (dummy + 3, 4, fun);
283 vax_store_struct_return (CORE_ADDR addr, CORE_ADDR sp)
285 write_register (1, addr);
289 vax_extract_return_value (struct type *valtype, char *regbuf, char *valbuf)
291 memcpy (valbuf, regbuf + REGISTER_BYTE (0), TYPE_LENGTH (valtype));
295 vax_store_return_value (struct type *valtype, char *valbuf)
297 deprecated_write_register_bytes (0, valbuf, TYPE_LENGTH (valtype));
301 vax_extract_struct_value_address (char *regbuf)
303 return (extract_address (regbuf + REGISTER_BYTE (0), 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, generic_target_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);