1 /* Print VAX instructions for GDB, the GNU debugger.
3 Copyright 1986, 1989, 1991, 1992, 1995, 1996, 1998, 1999, 2000,
4 2002, 2003, 2004 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
25 #include "opcode/vax.h"
31 #include "arch-utils.h"
32 #include "gdb_string.h"
38 static gdbarch_register_name_ftype vax_register_name
;
40 static gdbarch_skip_prologue_ftype vax_skip_prologue
;
41 static gdbarch_frame_num_args_ftype vax_frame_num_args
;
42 static gdbarch_deprecated_frame_chain_ftype vax_frame_chain
;
44 static gdbarch_deprecated_extract_return_value_ftype vax_extract_return_value
;
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 (deprecated_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 deprecated_get_frame_saved_regs (frame
)[regnum
] = next_addr
+= 4;
112 deprecated_get_frame_saved_regs (frame
)[SP_REGNUM
] = next_addr
+ 4;
113 if (regmask
& (1 << DEPRECATED_FP_REGNUM
))
114 deprecated_get_frame_saved_regs (frame
)[SP_REGNUM
] +=
115 4 + (4 * read_memory_integer (next_addr
+ 4, 4));
117 deprecated_get_frame_saved_regs (frame
)[PC_REGNUM
] = get_frame_base (frame
) + 16;
118 deprecated_get_frame_saved_regs (frame
)[DEPRECATED_FP_REGNUM
] = get_frame_base (frame
) + 12;
119 deprecated_get_frame_saved_regs (frame
)[VAX_AP_REGNUM
] = get_frame_base (frame
) + 8;
120 deprecated_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 return (read_memory_integer (get_frame_base (frame
) + 12, 4));
194 vax_push_dummy_frame (void)
196 CORE_ADDR sp
= read_register (SP_REGNUM
);
199 sp
= push_word (sp
, 0); /* arglist */
200 for (regnum
= 11; regnum
>= 0; regnum
--)
201 sp
= push_word (sp
, read_register (regnum
));
202 sp
= push_word (sp
, read_register (PC_REGNUM
));
203 sp
= push_word (sp
, read_register (DEPRECATED_FP_REGNUM
));
204 sp
= push_word (sp
, read_register (VAX_AP_REGNUM
));
205 sp
= push_word (sp
, (read_register (PS_REGNUM
) & 0xffef) + 0x2fff0000);
206 sp
= push_word (sp
, 0);
207 write_register (SP_REGNUM
, sp
);
208 write_register (DEPRECATED_FP_REGNUM
, sp
);
209 write_register (VAX_AP_REGNUM
, sp
+ (17 * 4));
215 CORE_ADDR fp
= read_register (DEPRECATED_FP_REGNUM
);
217 int regmask
= read_memory_integer (fp
+ 4, 4);
219 write_register (PS_REGNUM
,
221 | (read_register (PS_REGNUM
) & 0xffff0000));
222 write_register (PC_REGNUM
, read_memory_integer (fp
+ 16, 4));
223 write_register (DEPRECATED_FP_REGNUM
, read_memory_integer (fp
+ 12, 4));
224 write_register (VAX_AP_REGNUM
, read_memory_integer (fp
+ 8, 4));
226 for (regnum
= 0; regnum
< 12; regnum
++)
227 if (regmask
& (0x10000 << regnum
))
228 write_register (regnum
, read_memory_integer (fp
+= 4, 4));
229 fp
= fp
+ 4 + ((regmask
>> 30) & 3);
230 if (regmask
& 0x20000000)
232 regnum
= read_memory_integer (fp
, 4);
233 fp
+= (regnum
+ 1) * 4;
235 write_register (SP_REGNUM
, fp
);
236 flush_cached_frames ();
239 /* The VAX call dummy sequence:
241 calls #69, @#32323232
244 It is 8 bytes long. The address and argc are patched by
245 vax_fix_call_dummy(). */
246 static LONGEST vax_call_dummy_words
[] = { 0x329f69fb, 0x03323232 };
247 static int sizeof_vax_call_dummy_words
= sizeof(vax_call_dummy_words
);
250 vax_fix_call_dummy (char *dummy
, CORE_ADDR pc
, CORE_ADDR fun
, int nargs
,
251 struct value
**args
, struct type
*type
, int gcc_p
)
254 store_unsigned_integer (dummy
+ 3, 4, fun
);
258 vax_store_struct_return (CORE_ADDR addr
, CORE_ADDR sp
)
260 write_register (1, addr
);
264 vax_extract_return_value (struct type
*valtype
, char *regbuf
, char *valbuf
)
266 memcpy (valbuf
, regbuf
+ DEPRECATED_REGISTER_BYTE (0), TYPE_LENGTH (valtype
));
270 vax_store_return_value (struct type
*valtype
, char *valbuf
)
272 deprecated_write_register_bytes (0, valbuf
, TYPE_LENGTH (valtype
));
275 static const unsigned char *
276 vax_breakpoint_from_pc (CORE_ADDR
*pcptr
, int *lenptr
)
278 static const unsigned char vax_breakpoint
[] = { 3 };
280 *lenptr
= sizeof(vax_breakpoint
);
281 return (vax_breakpoint
);
284 /* Advance PC across any function entry prologue instructions
285 to reach some "real" code. */
288 vax_skip_prologue (CORE_ADDR pc
)
290 int op
= (unsigned char) read_memory_integer (pc
, 1);
292 pc
+= 2; /* skip brb */
294 pc
+= 3; /* skip brw */
296 && ((unsigned char) read_memory_integer (pc
+ 2, 1)) == 0x5E)
297 pc
+= 3; /* skip subl2 */
299 && ((unsigned char) read_memory_integer (pc
+ 1, 1)) == 0xAE
300 && ((unsigned char) read_memory_integer (pc
+ 3, 1)) == 0x5E)
301 pc
+= 4; /* skip movab */
303 && ((unsigned char) read_memory_integer (pc
+ 1, 1)) == 0xCE
304 && ((unsigned char) read_memory_integer (pc
+ 4, 1)) == 0x5E)
305 pc
+= 5; /* skip movab */
307 && ((unsigned char) read_memory_integer (pc
+ 1, 1)) == 0xEE
308 && ((unsigned char) read_memory_integer (pc
+ 6, 1)) == 0x5E)
309 pc
+= 7; /* skip movab */
314 vax_saved_pc_after_call (struct frame_info
*frame
)
316 return (DEPRECATED_FRAME_SAVED_PC(frame
));
319 /* Initialize the current architecture based on INFO. If possible, re-use an
320 architecture from ARCHES, which is a list of architectures already created
321 during this debugging session.
323 Called e.g. at program startup, when reading a core file, and when reading
326 static struct gdbarch
*
327 vax_gdbarch_init (struct gdbarch_info info
, struct gdbarch_list
*arches
)
329 struct gdbarch
*gdbarch
;
331 /* If there is already a candidate, use it. */
332 arches
= gdbarch_list_lookup_by_info (arches
, &info
);
334 return arches
->gdbarch
;
336 gdbarch
= gdbarch_alloc (&info
, NULL
);
338 /* NOTE: cagney/2002-12-06: This can be deleted when this arch is
339 ready to unwind the PC first (see frame.c:get_prev_frame()). */
340 set_gdbarch_deprecated_init_frame_pc (gdbarch
, deprecated_init_frame_pc_default
);
343 set_gdbarch_num_regs (gdbarch
, VAX_NUM_REGS
);
344 set_gdbarch_sp_regnum (gdbarch
, VAX_SP_REGNUM
);
345 set_gdbarch_deprecated_fp_regnum (gdbarch
, VAX_FP_REGNUM
);
346 set_gdbarch_pc_regnum (gdbarch
, VAX_PC_REGNUM
);
347 set_gdbarch_ps_regnum (gdbarch
, VAX_PS_REGNUM
);
349 set_gdbarch_register_name (gdbarch
, vax_register_name
);
350 set_gdbarch_deprecated_register_size (gdbarch
, VAX_REGISTER_SIZE
);
351 set_gdbarch_deprecated_register_bytes (gdbarch
, VAX_REGISTER_BYTES
);
352 set_gdbarch_deprecated_register_byte (gdbarch
, vax_register_byte
);
353 set_gdbarch_deprecated_register_raw_size (gdbarch
, vax_register_raw_size
);
354 set_gdbarch_deprecated_max_register_raw_size (gdbarch
, VAX_MAX_REGISTER_RAW_SIZE
);
355 set_gdbarch_deprecated_register_virtual_size (gdbarch
, vax_register_virtual_size
);
356 set_gdbarch_deprecated_max_register_virtual_size (gdbarch
,
357 VAX_MAX_REGISTER_VIRTUAL_SIZE
);
358 set_gdbarch_deprecated_register_virtual_type (gdbarch
, vax_register_virtual_type
);
360 /* Frame and stack info */
361 set_gdbarch_skip_prologue (gdbarch
, vax_skip_prologue
);
362 set_gdbarch_deprecated_saved_pc_after_call (gdbarch
, vax_saved_pc_after_call
);
364 set_gdbarch_frame_num_args (gdbarch
, vax_frame_num_args
);
365 set_gdbarch_frameless_function_invocation (gdbarch
,
366 generic_frameless_function_invocation_not
);
368 set_gdbarch_deprecated_frame_chain (gdbarch
, vax_frame_chain
);
369 set_gdbarch_deprecated_frame_saved_pc (gdbarch
, vax_frame_saved_pc
);
371 set_gdbarch_deprecated_frame_args_address (gdbarch
, vax_frame_args_address
);
373 set_gdbarch_deprecated_frame_init_saved_regs (gdbarch
, vax_frame_init_saved_regs
);
375 set_gdbarch_frame_args_skip (gdbarch
, 4);
377 set_gdbarch_inner_than (gdbarch
, core_addr_lessthan
);
379 /* Return value info */
380 set_gdbarch_deprecated_store_struct_return (gdbarch
, vax_store_struct_return
);
381 set_gdbarch_deprecated_extract_return_value (gdbarch
, vax_extract_return_value
);
382 set_gdbarch_deprecated_store_return_value (gdbarch
, vax_store_return_value
);
384 /* Call dummy info */
385 set_gdbarch_deprecated_push_dummy_frame (gdbarch
, vax_push_dummy_frame
);
386 set_gdbarch_deprecated_pop_frame (gdbarch
, vax_pop_frame
);
387 set_gdbarch_call_dummy_location (gdbarch
, ON_STACK
);
388 set_gdbarch_deprecated_call_dummy_words (gdbarch
, vax_call_dummy_words
);
389 set_gdbarch_deprecated_sizeof_call_dummy_words (gdbarch
, sizeof_vax_call_dummy_words
);
390 set_gdbarch_deprecated_fix_call_dummy (gdbarch
, vax_fix_call_dummy
);
391 set_gdbarch_deprecated_call_dummy_breakpoint_offset (gdbarch
, 7);
392 set_gdbarch_deprecated_use_generic_dummy_frames (gdbarch
, 0);
393 set_gdbarch_deprecated_pc_in_call_dummy (gdbarch
, deprecated_pc_in_call_dummy_on_stack
);
395 /* Breakpoint info */
396 set_gdbarch_breakpoint_from_pc (gdbarch
, vax_breakpoint_from_pc
);
399 set_gdbarch_function_start_offset (gdbarch
, 2);
400 set_gdbarch_believe_pcc_promotion (gdbarch
, 1);
402 /* Should be using push_dummy_call. */
403 set_gdbarch_deprecated_dummy_write_sp (gdbarch
, deprecated_write_sp
);
405 /* Hook in ABI-specific overrides, if they have been registered. */
406 gdbarch_init_osabi (info
, gdbarch
);
408 set_gdbarch_print_insn (gdbarch
, print_insn_vax
);
413 extern initialize_file_ftype _initialize_vax_tdep
; /* -Wmissing-prototypes */
416 _initialize_vax_tdep (void)
418 gdbarch_register (bfd_arch_vax
, vax_gdbarch_init
, NULL
);