| 1 | /* Target-dependent code for the HP PA architecture, for GDB. |
| 2 | Copyright 1986, 1987, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996 |
| 3 | Free Software Foundation, Inc. |
| 4 | |
| 5 | Contributed by the Center for Software Science at the |
| 6 | University of Utah (pa-gdb-bugs@cs.utah.edu). |
| 7 | |
| 8 | This file is part of GDB. |
| 9 | |
| 10 | This program is free software; you can redistribute it and/or modify |
| 11 | it under the terms of the GNU General Public License as published by |
| 12 | the Free Software Foundation; either version 2 of the License, or |
| 13 | (at your option) any later version. |
| 14 | |
| 15 | This program is distributed in the hope that it will be useful, |
| 16 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | GNU General Public License for more details. |
| 19 | |
| 20 | You should have received a copy of the GNU General Public License |
| 21 | along with this program; if not, write to the Free Software |
| 22 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 23 | |
| 24 | #include "defs.h" |
| 25 | #include "frame.h" |
| 26 | #include "inferior.h" |
| 27 | #include "value.h" |
| 28 | |
| 29 | /* For argument passing to the inferior */ |
| 30 | #include "symtab.h" |
| 31 | |
| 32 | #ifdef USG |
| 33 | #include <sys/types.h> |
| 34 | #endif |
| 35 | |
| 36 | #include <sys/param.h> |
| 37 | #include <signal.h> |
| 38 | |
| 39 | #ifdef COFF_ENCAPSULATE |
| 40 | #include "a.out.encap.h" |
| 41 | #else |
| 42 | #endif |
| 43 | #ifndef N_SET_MAGIC |
| 44 | #define N_SET_MAGIC(exec, val) ((exec).a_magic = (val)) |
| 45 | #endif |
| 46 | |
| 47 | /*#include <sys/user.h> After a.out.h */ |
| 48 | #include <sys/file.h> |
| 49 | #include "gdb_stat.h" |
| 50 | #include "wait.h" |
| 51 | |
| 52 | #include "gdbcore.h" |
| 53 | #include "gdbcmd.h" |
| 54 | #include "target.h" |
| 55 | #include "symfile.h" |
| 56 | #include "objfiles.h" |
| 57 | |
| 58 | static int extract_5_load PARAMS ((unsigned int)); |
| 59 | |
| 60 | static unsigned extract_5R_store PARAMS ((unsigned int)); |
| 61 | |
| 62 | static unsigned extract_5r_store PARAMS ((unsigned int)); |
| 63 | |
| 64 | static void find_dummy_frame_regs PARAMS ((struct frame_info *, |
| 65 | struct frame_saved_regs *)); |
| 66 | |
| 67 | static int find_proc_framesize PARAMS ((CORE_ADDR)); |
| 68 | |
| 69 | static int find_return_regnum PARAMS ((CORE_ADDR)); |
| 70 | |
| 71 | struct unwind_table_entry *find_unwind_entry PARAMS ((CORE_ADDR)); |
| 72 | |
| 73 | static int extract_17 PARAMS ((unsigned int)); |
| 74 | |
| 75 | static unsigned deposit_21 PARAMS ((unsigned int, unsigned int)); |
| 76 | |
| 77 | static int extract_21 PARAMS ((unsigned)); |
| 78 | |
| 79 | static unsigned deposit_14 PARAMS ((int, unsigned int)); |
| 80 | |
| 81 | static int extract_14 PARAMS ((unsigned)); |
| 82 | |
| 83 | static void unwind_command PARAMS ((char *, int)); |
| 84 | |
| 85 | static int low_sign_extend PARAMS ((unsigned int, unsigned int)); |
| 86 | |
| 87 | static int sign_extend PARAMS ((unsigned int, unsigned int)); |
| 88 | |
| 89 | static int restore_pc_queue PARAMS ((struct frame_saved_regs *)); |
| 90 | |
| 91 | static int hppa_alignof PARAMS ((struct type *)); |
| 92 | |
| 93 | CORE_ADDR frame_saved_pc PARAMS ((struct frame_info *)); |
| 94 | |
| 95 | static int prologue_inst_adjust_sp PARAMS ((unsigned long)); |
| 96 | |
| 97 | static int is_branch PARAMS ((unsigned long)); |
| 98 | |
| 99 | static int inst_saves_gr PARAMS ((unsigned long)); |
| 100 | |
| 101 | static int inst_saves_fr PARAMS ((unsigned long)); |
| 102 | |
| 103 | static int pc_in_interrupt_handler PARAMS ((CORE_ADDR)); |
| 104 | |
| 105 | static int pc_in_linker_stub PARAMS ((CORE_ADDR)); |
| 106 | |
| 107 | static int compare_unwind_entries PARAMS ((const void *, const void *)); |
| 108 | |
| 109 | static void read_unwind_info PARAMS ((struct objfile *)); |
| 110 | |
| 111 | static void internalize_unwinds PARAMS ((struct objfile *, |
| 112 | struct unwind_table_entry *, |
| 113 | asection *, unsigned int, |
| 114 | unsigned int, CORE_ADDR)); |
| 115 | static void pa_print_registers PARAMS ((char *, int, int)); |
| 116 | static void pa_print_fp_reg PARAMS ((int)); |
| 117 | |
| 118 | \f |
| 119 | /* Routines to extract various sized constants out of hppa |
| 120 | instructions. */ |
| 121 | |
| 122 | /* This assumes that no garbage lies outside of the lower bits of |
| 123 | value. */ |
| 124 | |
| 125 | static int |
| 126 | sign_extend (val, bits) |
| 127 | unsigned val, bits; |
| 128 | { |
| 129 | return (int)(val >> (bits - 1) ? (-1 << bits) | val : val); |
| 130 | } |
| 131 | |
| 132 | /* For many immediate values the sign bit is the low bit! */ |
| 133 | |
| 134 | static int |
| 135 | low_sign_extend (val, bits) |
| 136 | unsigned val, bits; |
| 137 | { |
| 138 | return (int)((val & 0x1 ? (-1 << (bits - 1)) : 0) | val >> 1); |
| 139 | } |
| 140 | |
| 141 | /* extract the immediate field from a ld{bhw}s instruction */ |
| 142 | |
| 143 | #if 0 |
| 144 | |
| 145 | unsigned |
| 146 | get_field (val, from, to) |
| 147 | unsigned val, from, to; |
| 148 | { |
| 149 | val = val >> 31 - to; |
| 150 | return val & ((1 << 32 - from) - 1); |
| 151 | } |
| 152 | |
| 153 | unsigned |
| 154 | set_field (val, from, to, new_val) |
| 155 | unsigned *val, from, to; |
| 156 | { |
| 157 | unsigned mask = ~((1 << (to - from + 1)) << (31 - from)); |
| 158 | return *val = *val & mask | (new_val << (31 - from)); |
| 159 | } |
| 160 | |
| 161 | /* extract a 3-bit space register number from a be, ble, mtsp or mfsp */ |
| 162 | |
| 163 | int |
| 164 | extract_3 (word) |
| 165 | unsigned word; |
| 166 | { |
| 167 | return GET_FIELD (word, 18, 18) << 2 | GET_FIELD (word, 16, 17); |
| 168 | } |
| 169 | |
| 170 | #endif |
| 171 | |
| 172 | static int |
| 173 | extract_5_load (word) |
| 174 | unsigned word; |
| 175 | { |
| 176 | return low_sign_extend (word >> 16 & MASK_5, 5); |
| 177 | } |
| 178 | |
| 179 | #if 0 |
| 180 | |
| 181 | /* extract the immediate field from a st{bhw}s instruction */ |
| 182 | |
| 183 | int |
| 184 | extract_5_store (word) |
| 185 | unsigned word; |
| 186 | { |
| 187 | return low_sign_extend (word & MASK_5, 5); |
| 188 | } |
| 189 | |
| 190 | #endif /* 0 */ |
| 191 | |
| 192 | /* extract the immediate field from a break instruction */ |
| 193 | |
| 194 | static unsigned |
| 195 | extract_5r_store (word) |
| 196 | unsigned word; |
| 197 | { |
| 198 | return (word & MASK_5); |
| 199 | } |
| 200 | |
| 201 | /* extract the immediate field from a {sr}sm instruction */ |
| 202 | |
| 203 | static unsigned |
| 204 | extract_5R_store (word) |
| 205 | unsigned word; |
| 206 | { |
| 207 | return (word >> 16 & MASK_5); |
| 208 | } |
| 209 | |
| 210 | /* extract an 11 bit immediate field */ |
| 211 | |
| 212 | #if 0 |
| 213 | |
| 214 | int |
| 215 | extract_11 (word) |
| 216 | unsigned word; |
| 217 | { |
| 218 | return low_sign_extend (word & MASK_11, 11); |
| 219 | } |
| 220 | |
| 221 | #endif |
| 222 | |
| 223 | /* extract a 14 bit immediate field */ |
| 224 | |
| 225 | static int |
| 226 | extract_14 (word) |
| 227 | unsigned word; |
| 228 | { |
| 229 | return low_sign_extend (word & MASK_14, 14); |
| 230 | } |
| 231 | |
| 232 | /* deposit a 14 bit constant in a word */ |
| 233 | |
| 234 | static unsigned |
| 235 | deposit_14 (opnd, word) |
| 236 | int opnd; |
| 237 | unsigned word; |
| 238 | { |
| 239 | unsigned sign = (opnd < 0 ? 1 : 0); |
| 240 | |
| 241 | return word | ((unsigned)opnd << 1 & MASK_14) | sign; |
| 242 | } |
| 243 | |
| 244 | /* extract a 21 bit constant */ |
| 245 | |
| 246 | static int |
| 247 | extract_21 (word) |
| 248 | unsigned word; |
| 249 | { |
| 250 | int val; |
| 251 | |
| 252 | word &= MASK_21; |
| 253 | word <<= 11; |
| 254 | val = GET_FIELD (word, 20, 20); |
| 255 | val <<= 11; |
| 256 | val |= GET_FIELD (word, 9, 19); |
| 257 | val <<= 2; |
| 258 | val |= GET_FIELD (word, 5, 6); |
| 259 | val <<= 5; |
| 260 | val |= GET_FIELD (word, 0, 4); |
| 261 | val <<= 2; |
| 262 | val |= GET_FIELD (word, 7, 8); |
| 263 | return sign_extend (val, 21) << 11; |
| 264 | } |
| 265 | |
| 266 | /* deposit a 21 bit constant in a word. Although 21 bit constants are |
| 267 | usually the top 21 bits of a 32 bit constant, we assume that only |
| 268 | the low 21 bits of opnd are relevant */ |
| 269 | |
| 270 | static unsigned |
| 271 | deposit_21 (opnd, word) |
| 272 | unsigned opnd, word; |
| 273 | { |
| 274 | unsigned val = 0; |
| 275 | |
| 276 | val |= GET_FIELD (opnd, 11 + 14, 11 + 18); |
| 277 | val <<= 2; |
| 278 | val |= GET_FIELD (opnd, 11 + 12, 11 + 13); |
| 279 | val <<= 2; |
| 280 | val |= GET_FIELD (opnd, 11 + 19, 11 + 20); |
| 281 | val <<= 11; |
| 282 | val |= GET_FIELD (opnd, 11 + 1, 11 + 11); |
| 283 | val <<= 1; |
| 284 | val |= GET_FIELD (opnd, 11 + 0, 11 + 0); |
| 285 | return word | val; |
| 286 | } |
| 287 | |
| 288 | /* extract a 12 bit constant from branch instructions */ |
| 289 | |
| 290 | #if 0 |
| 291 | |
| 292 | int |
| 293 | extract_12 (word) |
| 294 | unsigned word; |
| 295 | { |
| 296 | return sign_extend (GET_FIELD (word, 19, 28) | |
| 297 | GET_FIELD (word, 29, 29) << 10 | |
| 298 | (word & 0x1) << 11, 12) << 2; |
| 299 | } |
| 300 | |
| 301 | /* Deposit a 17 bit constant in an instruction (like bl). */ |
| 302 | |
| 303 | unsigned int |
| 304 | deposit_17 (opnd, word) |
| 305 | unsigned opnd, word; |
| 306 | { |
| 307 | word |= GET_FIELD (opnd, 15 + 0, 15 + 0); /* w */ |
| 308 | word |= GET_FIELD (opnd, 15 + 1, 15 + 5) << 16; /* w1 */ |
| 309 | word |= GET_FIELD (opnd, 15 + 6, 15 + 6) << 2; /* w2[10] */ |
| 310 | word |= GET_FIELD (opnd, 15 + 7, 15 + 16) << 3; /* w2[0..9] */ |
| 311 | |
| 312 | return word; |
| 313 | } |
| 314 | |
| 315 | #endif |
| 316 | |
| 317 | /* extract a 17 bit constant from branch instructions, returning the |
| 318 | 19 bit signed value. */ |
| 319 | |
| 320 | static int |
| 321 | extract_17 (word) |
| 322 | unsigned word; |
| 323 | { |
| 324 | return sign_extend (GET_FIELD (word, 19, 28) | |
| 325 | GET_FIELD (word, 29, 29) << 10 | |
| 326 | GET_FIELD (word, 11, 15) << 11 | |
| 327 | (word & 0x1) << 16, 17) << 2; |
| 328 | } |
| 329 | \f |
| 330 | |
| 331 | /* Compare the start address for two unwind entries returning 1 if |
| 332 | the first address is larger than the second, -1 if the second is |
| 333 | larger than the first, and zero if they are equal. */ |
| 334 | |
| 335 | static int |
| 336 | compare_unwind_entries (arg1, arg2) |
| 337 | const void *arg1; |
| 338 | const void *arg2; |
| 339 | { |
| 340 | const struct unwind_table_entry *a = arg1; |
| 341 | const struct unwind_table_entry *b = arg2; |
| 342 | |
| 343 | if (a->region_start > b->region_start) |
| 344 | return 1; |
| 345 | else if (a->region_start < b->region_start) |
| 346 | return -1; |
| 347 | else |
| 348 | return 0; |
| 349 | } |
| 350 | |
| 351 | static void |
| 352 | internalize_unwinds (objfile, table, section, entries, size, text_offset) |
| 353 | struct objfile *objfile; |
| 354 | struct unwind_table_entry *table; |
| 355 | asection *section; |
| 356 | unsigned int entries, size; |
| 357 | CORE_ADDR text_offset; |
| 358 | { |
| 359 | /* We will read the unwind entries into temporary memory, then |
| 360 | fill in the actual unwind table. */ |
| 361 | if (size > 0) |
| 362 | { |
| 363 | unsigned long tmp; |
| 364 | unsigned i; |
| 365 | char *buf = alloca (size); |
| 366 | |
| 367 | bfd_get_section_contents (objfile->obfd, section, buf, 0, size); |
| 368 | |
| 369 | /* Now internalize the information being careful to handle host/target |
| 370 | endian issues. */ |
| 371 | for (i = 0; i < entries; i++) |
| 372 | { |
| 373 | table[i].region_start = bfd_get_32 (objfile->obfd, |
| 374 | (bfd_byte *)buf); |
| 375 | table[i].region_start += text_offset; |
| 376 | buf += 4; |
| 377 | table[i].region_end = bfd_get_32 (objfile->obfd, (bfd_byte *)buf); |
| 378 | table[i].region_end += text_offset; |
| 379 | buf += 4; |
| 380 | tmp = bfd_get_32 (objfile->obfd, (bfd_byte *)buf); |
| 381 | buf += 4; |
| 382 | table[i].Cannot_unwind = (tmp >> 31) & 0x1; |
| 383 | table[i].Millicode = (tmp >> 30) & 0x1; |
| 384 | table[i].Millicode_save_sr0 = (tmp >> 29) & 0x1; |
| 385 | table[i].Region_description = (tmp >> 27) & 0x3; |
| 386 | table[i].reserved1 = (tmp >> 26) & 0x1; |
| 387 | table[i].Entry_SR = (tmp >> 25) & 0x1; |
| 388 | table[i].Entry_FR = (tmp >> 21) & 0xf; |
| 389 | table[i].Entry_GR = (tmp >> 16) & 0x1f; |
| 390 | table[i].Args_stored = (tmp >> 15) & 0x1; |
| 391 | table[i].Variable_Frame = (tmp >> 14) & 0x1; |
| 392 | table[i].Separate_Package_Body = (tmp >> 13) & 0x1; |
| 393 | table[i].Frame_Extension_Millicode = (tmp >> 12 ) & 0x1; |
| 394 | table[i].Stack_Overflow_Check = (tmp >> 11) & 0x1; |
| 395 | table[i].Two_Instruction_SP_Increment = (tmp >> 10) & 0x1; |
| 396 | table[i].Ada_Region = (tmp >> 9) & 0x1; |
| 397 | table[i].reserved2 = (tmp >> 5) & 0xf; |
| 398 | table[i].Save_SP = (tmp >> 4) & 0x1; |
| 399 | table[i].Save_RP = (tmp >> 3) & 0x1; |
| 400 | table[i].Save_MRP_in_frame = (tmp >> 2) & 0x1; |
| 401 | table[i].extn_ptr_defined = (tmp >> 1) & 0x1; |
| 402 | table[i].Cleanup_defined = tmp & 0x1; |
| 403 | tmp = bfd_get_32 (objfile->obfd, (bfd_byte *)buf); |
| 404 | buf += 4; |
| 405 | table[i].MPE_XL_interrupt_marker = (tmp >> 31) & 0x1; |
| 406 | table[i].HP_UX_interrupt_marker = (tmp >> 30) & 0x1; |
| 407 | table[i].Large_frame = (tmp >> 29) & 0x1; |
| 408 | table[i].reserved4 = (tmp >> 27) & 0x3; |
| 409 | table[i].Total_frame_size = tmp & 0x7ffffff; |
| 410 | } |
| 411 | } |
| 412 | } |
| 413 | |
| 414 | /* Read in the backtrace information stored in the `$UNWIND_START$' section of |
| 415 | the object file. This info is used mainly by find_unwind_entry() to find |
| 416 | out the stack frame size and frame pointer used by procedures. We put |
| 417 | everything on the psymbol obstack in the objfile so that it automatically |
| 418 | gets freed when the objfile is destroyed. */ |
| 419 | |
| 420 | static void |
| 421 | read_unwind_info (objfile) |
| 422 | struct objfile *objfile; |
| 423 | { |
| 424 | asection *unwind_sec, *elf_unwind_sec, *stub_unwind_sec; |
| 425 | unsigned unwind_size, elf_unwind_size, stub_unwind_size, total_size; |
| 426 | unsigned index, unwind_entries, elf_unwind_entries; |
| 427 | unsigned stub_entries, total_entries; |
| 428 | CORE_ADDR text_offset; |
| 429 | struct obj_unwind_info *ui; |
| 430 | |
| 431 | text_offset = ANOFFSET (objfile->section_offsets, 0); |
| 432 | ui = (struct obj_unwind_info *)obstack_alloc (&objfile->psymbol_obstack, |
| 433 | sizeof (struct obj_unwind_info)); |
| 434 | |
| 435 | ui->table = NULL; |
| 436 | ui->cache = NULL; |
| 437 | ui->last = -1; |
| 438 | |
| 439 | /* Get hooks to all unwind sections. Note there is no linker-stub unwind |
| 440 | section in ELF at the moment. */ |
| 441 | unwind_sec = bfd_get_section_by_name (objfile->obfd, "$UNWIND_START$"); |
| 442 | elf_unwind_sec = bfd_get_section_by_name (objfile->obfd, ".PARISC.unwind"); |
| 443 | stub_unwind_sec = bfd_get_section_by_name (objfile->obfd, "$UNWIND_END$"); |
| 444 | |
| 445 | /* Get sizes and unwind counts for all sections. */ |
| 446 | if (unwind_sec) |
| 447 | { |
| 448 | unwind_size = bfd_section_size (objfile->obfd, unwind_sec); |
| 449 | unwind_entries = unwind_size / UNWIND_ENTRY_SIZE; |
| 450 | } |
| 451 | else |
| 452 | { |
| 453 | unwind_size = 0; |
| 454 | unwind_entries = 0; |
| 455 | } |
| 456 | |
| 457 | if (elf_unwind_sec) |
| 458 | { |
| 459 | elf_unwind_size = bfd_section_size (objfile->obfd, elf_unwind_sec); |
| 460 | elf_unwind_entries = elf_unwind_size / UNWIND_ENTRY_SIZE; |
| 461 | } |
| 462 | else |
| 463 | { |
| 464 | elf_unwind_size = 0; |
| 465 | elf_unwind_entries = 0; |
| 466 | } |
| 467 | |
| 468 | if (stub_unwind_sec) |
| 469 | { |
| 470 | stub_unwind_size = bfd_section_size (objfile->obfd, stub_unwind_sec); |
| 471 | stub_entries = stub_unwind_size / STUB_UNWIND_ENTRY_SIZE; |
| 472 | } |
| 473 | else |
| 474 | { |
| 475 | stub_unwind_size = 0; |
| 476 | stub_entries = 0; |
| 477 | } |
| 478 | |
| 479 | /* Compute total number of unwind entries and their total size. */ |
| 480 | total_entries = unwind_entries + elf_unwind_entries + stub_entries; |
| 481 | total_size = total_entries * sizeof (struct unwind_table_entry); |
| 482 | |
| 483 | /* Allocate memory for the unwind table. */ |
| 484 | ui->table = obstack_alloc (&objfile->psymbol_obstack, total_size); |
| 485 | ui->last = total_entries - 1; |
| 486 | |
| 487 | /* Internalize the standard unwind entries. */ |
| 488 | index = 0; |
| 489 | internalize_unwinds (objfile, &ui->table[index], unwind_sec, |
| 490 | unwind_entries, unwind_size, text_offset); |
| 491 | index += unwind_entries; |
| 492 | internalize_unwinds (objfile, &ui->table[index], elf_unwind_sec, |
| 493 | elf_unwind_entries, elf_unwind_size, text_offset); |
| 494 | index += elf_unwind_entries; |
| 495 | |
| 496 | /* Now internalize the stub unwind entries. */ |
| 497 | if (stub_unwind_size > 0) |
| 498 | { |
| 499 | unsigned int i; |
| 500 | char *buf = alloca (stub_unwind_size); |
| 501 | |
| 502 | /* Read in the stub unwind entries. */ |
| 503 | bfd_get_section_contents (objfile->obfd, stub_unwind_sec, buf, |
| 504 | 0, stub_unwind_size); |
| 505 | |
| 506 | /* Now convert them into regular unwind entries. */ |
| 507 | for (i = 0; i < stub_entries; i++, index++) |
| 508 | { |
| 509 | /* Clear out the next unwind entry. */ |
| 510 | memset (&ui->table[index], 0, sizeof (struct unwind_table_entry)); |
| 511 | |
| 512 | /* Convert offset & size into region_start and region_end. |
| 513 | Stuff away the stub type into "reserved" fields. */ |
| 514 | ui->table[index].region_start = bfd_get_32 (objfile->obfd, |
| 515 | (bfd_byte *) buf); |
| 516 | ui->table[index].region_start += text_offset; |
| 517 | buf += 4; |
| 518 | ui->table[index].stub_type = bfd_get_8 (objfile->obfd, |
| 519 | (bfd_byte *) buf); |
| 520 | buf += 2; |
| 521 | ui->table[index].region_end |
| 522 | = ui->table[index].region_start + 4 * |
| 523 | (bfd_get_16 (objfile->obfd, (bfd_byte *) buf) - 1); |
| 524 | buf += 2; |
| 525 | } |
| 526 | |
| 527 | } |
| 528 | |
| 529 | /* Unwind table needs to be kept sorted. */ |
| 530 | qsort (ui->table, total_entries, sizeof (struct unwind_table_entry), |
| 531 | compare_unwind_entries); |
| 532 | |
| 533 | /* Keep a pointer to the unwind information. */ |
| 534 | objfile->obj_private = (PTR) ui; |
| 535 | } |
| 536 | |
| 537 | /* Lookup the unwind (stack backtrace) info for the given PC. We search all |
| 538 | of the objfiles seeking the unwind table entry for this PC. Each objfile |
| 539 | contains a sorted list of struct unwind_table_entry. Since we do a binary |
| 540 | search of the unwind tables, we depend upon them to be sorted. */ |
| 541 | |
| 542 | struct unwind_table_entry * |
| 543 | find_unwind_entry(pc) |
| 544 | CORE_ADDR pc; |
| 545 | { |
| 546 | int first, middle, last; |
| 547 | struct objfile *objfile; |
| 548 | |
| 549 | ALL_OBJFILES (objfile) |
| 550 | { |
| 551 | struct obj_unwind_info *ui; |
| 552 | |
| 553 | ui = OBJ_UNWIND_INFO (objfile); |
| 554 | |
| 555 | if (!ui) |
| 556 | { |
| 557 | read_unwind_info (objfile); |
| 558 | ui = OBJ_UNWIND_INFO (objfile); |
| 559 | } |
| 560 | |
| 561 | /* First, check the cache */ |
| 562 | |
| 563 | if (ui->cache |
| 564 | && pc >= ui->cache->region_start |
| 565 | && pc <= ui->cache->region_end) |
| 566 | return ui->cache; |
| 567 | |
| 568 | /* Not in the cache, do a binary search */ |
| 569 | |
| 570 | first = 0; |
| 571 | last = ui->last; |
| 572 | |
| 573 | while (first <= last) |
| 574 | { |
| 575 | middle = (first + last) / 2; |
| 576 | if (pc >= ui->table[middle].region_start |
| 577 | && pc <= ui->table[middle].region_end) |
| 578 | { |
| 579 | ui->cache = &ui->table[middle]; |
| 580 | return &ui->table[middle]; |
| 581 | } |
| 582 | |
| 583 | if (pc < ui->table[middle].region_start) |
| 584 | last = middle - 1; |
| 585 | else |
| 586 | first = middle + 1; |
| 587 | } |
| 588 | } /* ALL_OBJFILES() */ |
| 589 | return NULL; |
| 590 | } |
| 591 | |
| 592 | /* Return the adjustment necessary to make for addresses on the stack |
| 593 | as presented by hpread.c. |
| 594 | |
| 595 | This is necessary because of the stack direction on the PA and the |
| 596 | bizarre way in which someone (?) decided they wanted to handle |
| 597 | frame pointerless code in GDB. */ |
| 598 | int |
| 599 | hpread_adjust_stack_address (func_addr) |
| 600 | CORE_ADDR func_addr; |
| 601 | { |
| 602 | struct unwind_table_entry *u; |
| 603 | |
| 604 | u = find_unwind_entry (func_addr); |
| 605 | if (!u) |
| 606 | return 0; |
| 607 | else |
| 608 | return u->Total_frame_size << 3; |
| 609 | } |
| 610 | |
| 611 | /* Called to determine if PC is in an interrupt handler of some |
| 612 | kind. */ |
| 613 | |
| 614 | static int |
| 615 | pc_in_interrupt_handler (pc) |
| 616 | CORE_ADDR pc; |
| 617 | { |
| 618 | struct unwind_table_entry *u; |
| 619 | struct minimal_symbol *msym_us; |
| 620 | |
| 621 | u = find_unwind_entry (pc); |
| 622 | if (!u) |
| 623 | return 0; |
| 624 | |
| 625 | /* Oh joys. HPUX sets the interrupt bit for _sigreturn even though |
| 626 | its frame isn't a pure interrupt frame. Deal with this. */ |
| 627 | msym_us = lookup_minimal_symbol_by_pc (pc); |
| 628 | |
| 629 | return u->HP_UX_interrupt_marker && !IN_SIGTRAMP (pc, SYMBOL_NAME (msym_us)); |
| 630 | } |
| 631 | |
| 632 | /* Called when no unwind descriptor was found for PC. Returns 1 if it |
| 633 | appears that PC is in a linker stub. */ |
| 634 | |
| 635 | static int |
| 636 | pc_in_linker_stub (pc) |
| 637 | CORE_ADDR pc; |
| 638 | { |
| 639 | int found_magic_instruction = 0; |
| 640 | int i; |
| 641 | char buf[4]; |
| 642 | |
| 643 | /* If unable to read memory, assume pc is not in a linker stub. */ |
| 644 | if (target_read_memory (pc, buf, 4) != 0) |
| 645 | return 0; |
| 646 | |
| 647 | /* We are looking for something like |
| 648 | |
| 649 | ; $$dyncall jams RP into this special spot in the frame (RP') |
| 650 | ; before calling the "call stub" |
| 651 | ldw -18(sp),rp |
| 652 | |
| 653 | ldsid (rp),r1 ; Get space associated with RP into r1 |
| 654 | mtsp r1,sp ; Move it into space register 0 |
| 655 | be,n 0(sr0),rp) ; back to your regularly scheduled program |
| 656 | */ |
| 657 | |
| 658 | /* Maximum known linker stub size is 4 instructions. Search forward |
| 659 | from the given PC, then backward. */ |
| 660 | for (i = 0; i < 4; i++) |
| 661 | { |
| 662 | /* If we hit something with an unwind, stop searching this direction. */ |
| 663 | |
| 664 | if (find_unwind_entry (pc + i * 4) != 0) |
| 665 | break; |
| 666 | |
| 667 | /* Check for ldsid (rp),r1 which is the magic instruction for a |
| 668 | return from a cross-space function call. */ |
| 669 | if (read_memory_integer (pc + i * 4, 4) == 0x004010a1) |
| 670 | { |
| 671 | found_magic_instruction = 1; |
| 672 | break; |
| 673 | } |
| 674 | /* Add code to handle long call/branch and argument relocation stubs |
| 675 | here. */ |
| 676 | } |
| 677 | |
| 678 | if (found_magic_instruction != 0) |
| 679 | return 1; |
| 680 | |
| 681 | /* Now look backward. */ |
| 682 | for (i = 0; i < 4; i++) |
| 683 | { |
| 684 | /* If we hit something with an unwind, stop searching this direction. */ |
| 685 | |
| 686 | if (find_unwind_entry (pc - i * 4) != 0) |
| 687 | break; |
| 688 | |
| 689 | /* Check for ldsid (rp),r1 which is the magic instruction for a |
| 690 | return from a cross-space function call. */ |
| 691 | if (read_memory_integer (pc - i * 4, 4) == 0x004010a1) |
| 692 | { |
| 693 | found_magic_instruction = 1; |
| 694 | break; |
| 695 | } |
| 696 | /* Add code to handle long call/branch and argument relocation stubs |
| 697 | here. */ |
| 698 | } |
| 699 | return found_magic_instruction; |
| 700 | } |
| 701 | |
| 702 | static int |
| 703 | find_return_regnum(pc) |
| 704 | CORE_ADDR pc; |
| 705 | { |
| 706 | struct unwind_table_entry *u; |
| 707 | |
| 708 | u = find_unwind_entry (pc); |
| 709 | |
| 710 | if (!u) |
| 711 | return RP_REGNUM; |
| 712 | |
| 713 | if (u->Millicode) |
| 714 | return 31; |
| 715 | |
| 716 | return RP_REGNUM; |
| 717 | } |
| 718 | |
| 719 | /* Return size of frame, or -1 if we should use a frame pointer. */ |
| 720 | static int |
| 721 | find_proc_framesize (pc) |
| 722 | CORE_ADDR pc; |
| 723 | { |
| 724 | struct unwind_table_entry *u; |
| 725 | struct minimal_symbol *msym_us; |
| 726 | |
| 727 | u = find_unwind_entry (pc); |
| 728 | |
| 729 | if (!u) |
| 730 | { |
| 731 | if (pc_in_linker_stub (pc)) |
| 732 | /* Linker stubs have a zero size frame. */ |
| 733 | return 0; |
| 734 | else |
| 735 | return -1; |
| 736 | } |
| 737 | |
| 738 | msym_us = lookup_minimal_symbol_by_pc (pc); |
| 739 | |
| 740 | /* If Save_SP is set, and we're not in an interrupt or signal caller, |
| 741 | then we have a frame pointer. Use it. */ |
| 742 | if (u->Save_SP && !pc_in_interrupt_handler (pc) |
| 743 | && !IN_SIGTRAMP (pc, SYMBOL_NAME (msym_us))) |
| 744 | return -1; |
| 745 | |
| 746 | return u->Total_frame_size << 3; |
| 747 | } |
| 748 | |
| 749 | /* Return offset from sp at which rp is saved, or 0 if not saved. */ |
| 750 | static int rp_saved PARAMS ((CORE_ADDR)); |
| 751 | |
| 752 | static int |
| 753 | rp_saved (pc) |
| 754 | CORE_ADDR pc; |
| 755 | { |
| 756 | struct unwind_table_entry *u; |
| 757 | |
| 758 | u = find_unwind_entry (pc); |
| 759 | |
| 760 | if (!u) |
| 761 | { |
| 762 | if (pc_in_linker_stub (pc)) |
| 763 | /* This is the so-called RP'. */ |
| 764 | return -24; |
| 765 | else |
| 766 | return 0; |
| 767 | } |
| 768 | |
| 769 | if (u->Save_RP) |
| 770 | return -20; |
| 771 | else if (u->stub_type != 0) |
| 772 | { |
| 773 | switch (u->stub_type) |
| 774 | { |
| 775 | case EXPORT: |
| 776 | case IMPORT: |
| 777 | return -24; |
| 778 | case PARAMETER_RELOCATION: |
| 779 | return -8; |
| 780 | default: |
| 781 | return 0; |
| 782 | } |
| 783 | } |
| 784 | else |
| 785 | return 0; |
| 786 | } |
| 787 | \f |
| 788 | int |
| 789 | frameless_function_invocation (frame) |
| 790 | struct frame_info *frame; |
| 791 | { |
| 792 | struct unwind_table_entry *u; |
| 793 | |
| 794 | u = find_unwind_entry (frame->pc); |
| 795 | |
| 796 | if (u == 0) |
| 797 | return 0; |
| 798 | |
| 799 | return (u->Total_frame_size == 0 && u->stub_type == 0); |
| 800 | } |
| 801 | |
| 802 | CORE_ADDR |
| 803 | saved_pc_after_call (frame) |
| 804 | struct frame_info *frame; |
| 805 | { |
| 806 | int ret_regnum; |
| 807 | CORE_ADDR pc; |
| 808 | struct unwind_table_entry *u; |
| 809 | |
| 810 | ret_regnum = find_return_regnum (get_frame_pc (frame)); |
| 811 | pc = read_register (ret_regnum) & ~0x3; |
| 812 | |
| 813 | /* If PC is in a linker stub, then we need to dig the address |
| 814 | the stub will return to out of the stack. */ |
| 815 | u = find_unwind_entry (pc); |
| 816 | if (u && u->stub_type != 0) |
| 817 | return frame_saved_pc (frame); |
| 818 | else |
| 819 | return pc; |
| 820 | } |
| 821 | \f |
| 822 | CORE_ADDR |
| 823 | frame_saved_pc (frame) |
| 824 | struct frame_info *frame; |
| 825 | { |
| 826 | CORE_ADDR pc = get_frame_pc (frame); |
| 827 | struct unwind_table_entry *u; |
| 828 | |
| 829 | /* BSD, HPUX & OSF1 all lay out the hardware state in the same manner |
| 830 | at the base of the frame in an interrupt handler. Registers within |
| 831 | are saved in the exact same order as GDB numbers registers. How |
| 832 | convienent. */ |
| 833 | if (pc_in_interrupt_handler (pc)) |
| 834 | return read_memory_integer (frame->frame + PC_REGNUM * 4, 4) & ~0x3; |
| 835 | |
| 836 | #ifdef FRAME_SAVED_PC_IN_SIGTRAMP |
| 837 | /* Deal with signal handler caller frames too. */ |
| 838 | if (frame->signal_handler_caller) |
| 839 | { |
| 840 | CORE_ADDR rp; |
| 841 | FRAME_SAVED_PC_IN_SIGTRAMP (frame, &rp); |
| 842 | return rp & ~0x3; |
| 843 | } |
| 844 | #endif |
| 845 | |
| 846 | if (frameless_function_invocation (frame)) |
| 847 | { |
| 848 | int ret_regnum; |
| 849 | |
| 850 | ret_regnum = find_return_regnum (pc); |
| 851 | |
| 852 | /* If the next frame is an interrupt frame or a signal |
| 853 | handler caller, then we need to look in the saved |
| 854 | register area to get the return pointer (the values |
| 855 | in the registers may not correspond to anything useful). */ |
| 856 | if (frame->next |
| 857 | && (frame->next->signal_handler_caller |
| 858 | || pc_in_interrupt_handler (frame->next->pc))) |
| 859 | { |
| 860 | struct frame_saved_regs saved_regs; |
| 861 | |
| 862 | get_frame_saved_regs (frame->next, &saved_regs); |
| 863 | if (read_memory_integer (saved_regs.regs[FLAGS_REGNUM], 4) & 0x2) |
| 864 | { |
| 865 | pc = read_memory_integer (saved_regs.regs[31], 4) & ~0x3; |
| 866 | |
| 867 | /* Syscalls are really two frames. The syscall stub itself |
| 868 | with a return pointer in %rp and the kernel call with |
| 869 | a return pointer in %r31. We return the %rp variant |
| 870 | if %r31 is the same as frame->pc. */ |
| 871 | if (pc == frame->pc) |
| 872 | pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3; |
| 873 | } |
| 874 | else |
| 875 | pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3; |
| 876 | } |
| 877 | else |
| 878 | pc = read_register (ret_regnum) & ~0x3; |
| 879 | } |
| 880 | else |
| 881 | { |
| 882 | int rp_offset; |
| 883 | |
| 884 | restart: |
| 885 | rp_offset = rp_saved (pc); |
| 886 | /* Similar to code in frameless function case. If the next |
| 887 | frame is a signal or interrupt handler, then dig the right |
| 888 | information out of the saved register info. */ |
| 889 | if (rp_offset == 0 |
| 890 | && frame->next |
| 891 | && (frame->next->signal_handler_caller |
| 892 | || pc_in_interrupt_handler (frame->next->pc))) |
| 893 | { |
| 894 | struct frame_saved_regs saved_regs; |
| 895 | |
| 896 | get_frame_saved_regs (frame->next, &saved_regs); |
| 897 | if (read_memory_integer (saved_regs.regs[FLAGS_REGNUM], 4) & 0x2) |
| 898 | { |
| 899 | pc = read_memory_integer (saved_regs.regs[31], 4) & ~0x3; |
| 900 | |
| 901 | /* Syscalls are really two frames. The syscall stub itself |
| 902 | with a return pointer in %rp and the kernel call with |
| 903 | a return pointer in %r31. We return the %rp variant |
| 904 | if %r31 is the same as frame->pc. */ |
| 905 | if (pc == frame->pc) |
| 906 | pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3; |
| 907 | } |
| 908 | else |
| 909 | pc = read_memory_integer (saved_regs.regs[RP_REGNUM], 4) & ~0x3; |
| 910 | } |
| 911 | else if (rp_offset == 0) |
| 912 | pc = read_register (RP_REGNUM) & ~0x3; |
| 913 | else |
| 914 | pc = read_memory_integer (frame->frame + rp_offset, 4) & ~0x3; |
| 915 | } |
| 916 | |
| 917 | /* If PC is inside a linker stub, then dig out the address the stub |
| 918 | will return to. |
| 919 | |
| 920 | Don't do this for long branch stubs. Why? For some unknown reason |
| 921 | _start is marked as a long branch stub in hpux10. */ |
| 922 | u = find_unwind_entry (pc); |
| 923 | if (u && u->stub_type != 0 |
| 924 | && u->stub_type != LONG_BRANCH) |
| 925 | { |
| 926 | unsigned int insn; |
| 927 | |
| 928 | /* If this is a dynamic executable, and we're in a signal handler, |
| 929 | then the call chain will eventually point us into the stub for |
| 930 | _sigreturn. Unlike most cases, we'll be pointed to the branch |
| 931 | to the real sigreturn rather than the code after the real branch!. |
| 932 | |
| 933 | Else, try to dig the address the stub will return to in the normal |
| 934 | fashion. */ |
| 935 | insn = read_memory_integer (pc, 4); |
| 936 | if ((insn & 0xfc00e000) == 0xe8000000) |
| 937 | return (pc + extract_17 (insn) + 8) & ~0x3; |
| 938 | else |
| 939 | goto restart; |
| 940 | } |
| 941 | |
| 942 | return pc; |
| 943 | } |
| 944 | \f |
| 945 | /* We need to correct the PC and the FP for the outermost frame when we are |
| 946 | in a system call. */ |
| 947 | |
| 948 | void |
| 949 | init_extra_frame_info (fromleaf, frame) |
| 950 | int fromleaf; |
| 951 | struct frame_info *frame; |
| 952 | { |
| 953 | int flags; |
| 954 | int framesize; |
| 955 | |
| 956 | if (frame->next && !fromleaf) |
| 957 | return; |
| 958 | |
| 959 | /* If the next frame represents a frameless function invocation |
| 960 | then we have to do some adjustments that are normally done by |
| 961 | FRAME_CHAIN. (FRAME_CHAIN is not called in this case.) */ |
| 962 | if (fromleaf) |
| 963 | { |
| 964 | /* Find the framesize of *this* frame without peeking at the PC |
| 965 | in the current frame structure (it isn't set yet). */ |
| 966 | framesize = find_proc_framesize (FRAME_SAVED_PC (get_next_frame (frame))); |
| 967 | |
| 968 | /* Now adjust our base frame accordingly. If we have a frame pointer |
| 969 | use it, else subtract the size of this frame from the current |
| 970 | frame. (we always want frame->frame to point at the lowest address |
| 971 | in the frame). */ |
| 972 | if (framesize == -1) |
| 973 | frame->frame = read_register (FP_REGNUM); |
| 974 | else |
| 975 | frame->frame -= framesize; |
| 976 | return; |
| 977 | } |
| 978 | |
| 979 | flags = read_register (FLAGS_REGNUM); |
| 980 | if (flags & 2) /* In system call? */ |
| 981 | frame->pc = read_register (31) & ~0x3; |
| 982 | |
| 983 | /* The outermost frame is always derived from PC-framesize |
| 984 | |
| 985 | One might think frameless innermost frames should have |
| 986 | a frame->frame that is the same as the parent's frame->frame. |
| 987 | That is wrong; frame->frame in that case should be the *high* |
| 988 | address of the parent's frame. It's complicated as hell to |
| 989 | explain, but the parent *always* creates some stack space for |
| 990 | the child. So the child actually does have a frame of some |
| 991 | sorts, and its base is the high address in its parent's frame. */ |
| 992 | framesize = find_proc_framesize(frame->pc); |
| 993 | if (framesize == -1) |
| 994 | frame->frame = read_register (FP_REGNUM); |
| 995 | else |
| 996 | frame->frame = read_register (SP_REGNUM) - framesize; |
| 997 | } |
| 998 | \f |
| 999 | /* Given a GDB frame, determine the address of the calling function's frame. |
| 1000 | This will be used to create a new GDB frame struct, and then |
| 1001 | INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame. |
| 1002 | |
| 1003 | This may involve searching through prologues for several functions |
| 1004 | at boundaries where GCC calls HP C code, or where code which has |
| 1005 | a frame pointer calls code without a frame pointer. */ |
| 1006 | |
| 1007 | CORE_ADDR |
| 1008 | frame_chain (frame) |
| 1009 | struct frame_info *frame; |
| 1010 | { |
| 1011 | int my_framesize, caller_framesize; |
| 1012 | struct unwind_table_entry *u; |
| 1013 | CORE_ADDR frame_base; |
| 1014 | struct frame_info *tmp_frame; |
| 1015 | |
| 1016 | /* Handle HPUX, BSD, and OSF1 style interrupt frames first. These |
| 1017 | are easy; at *sp we have a full save state strucutre which we can |
| 1018 | pull the old stack pointer from. Also see frame_saved_pc for |
| 1019 | code to dig a saved PC out of the save state structure. */ |
| 1020 | if (pc_in_interrupt_handler (frame->pc)) |
| 1021 | frame_base = read_memory_integer (frame->frame + SP_REGNUM * 4, 4); |
| 1022 | #ifdef FRAME_BASE_BEFORE_SIGTRAMP |
| 1023 | else if (frame->signal_handler_caller) |
| 1024 | { |
| 1025 | FRAME_BASE_BEFORE_SIGTRAMP (frame, &frame_base); |
| 1026 | } |
| 1027 | #endif |
| 1028 | else |
| 1029 | frame_base = frame->frame; |
| 1030 | |
| 1031 | /* Get frame sizes for the current frame and the frame of the |
| 1032 | caller. */ |
| 1033 | my_framesize = find_proc_framesize (frame->pc); |
| 1034 | caller_framesize = find_proc_framesize (FRAME_SAVED_PC(frame)); |
| 1035 | |
| 1036 | /* If caller does not have a frame pointer, then its frame |
| 1037 | can be found at current_frame - caller_framesize. */ |
| 1038 | if (caller_framesize != -1) |
| 1039 | return frame_base - caller_framesize; |
| 1040 | |
| 1041 | /* Both caller and callee have frame pointers and are GCC compiled |
| 1042 | (SAVE_SP bit in unwind descriptor is on for both functions. |
| 1043 | The previous frame pointer is found at the top of the current frame. */ |
| 1044 | if (caller_framesize == -1 && my_framesize == -1) |
| 1045 | return read_memory_integer (frame_base, 4); |
| 1046 | |
| 1047 | /* Caller has a frame pointer, but callee does not. This is a little |
| 1048 | more difficult as GCC and HP C lay out locals and callee register save |
| 1049 | areas very differently. |
| 1050 | |
| 1051 | The previous frame pointer could be in a register, or in one of |
| 1052 | several areas on the stack. |
| 1053 | |
| 1054 | Walk from the current frame to the innermost frame examining |
| 1055 | unwind descriptors to determine if %r3 ever gets saved into the |
| 1056 | stack. If so return whatever value got saved into the stack. |
| 1057 | If it was never saved in the stack, then the value in %r3 is still |
| 1058 | valid, so use it. |
| 1059 | |
| 1060 | We use information from unwind descriptors to determine if %r3 |
| 1061 | is saved into the stack (Entry_GR field has this information). */ |
| 1062 | |
| 1063 | tmp_frame = frame; |
| 1064 | while (tmp_frame) |
| 1065 | { |
| 1066 | u = find_unwind_entry (tmp_frame->pc); |
| 1067 | |
| 1068 | if (!u) |
| 1069 | { |
| 1070 | /* We could find this information by examining prologues. I don't |
| 1071 | think anyone has actually written any tools (not even "strip") |
| 1072 | which leave them out of an executable, so maybe this is a moot |
| 1073 | point. */ |
| 1074 | warning ("Unable to find unwind for PC 0x%x -- Help!", tmp_frame->pc); |
| 1075 | return 0; |
| 1076 | } |
| 1077 | |
| 1078 | /* Entry_GR specifies the number of callee-saved general registers |
| 1079 | saved in the stack. It starts at %r3, so %r3 would be 1. */ |
| 1080 | if (u->Entry_GR >= 1 || u->Save_SP |
| 1081 | || tmp_frame->signal_handler_caller |
| 1082 | || pc_in_interrupt_handler (tmp_frame->pc)) |
| 1083 | break; |
| 1084 | else |
| 1085 | tmp_frame = tmp_frame->next; |
| 1086 | } |
| 1087 | |
| 1088 | if (tmp_frame) |
| 1089 | { |
| 1090 | /* We may have walked down the chain into a function with a frame |
| 1091 | pointer. */ |
| 1092 | if (u->Save_SP |
| 1093 | && !tmp_frame->signal_handler_caller |
| 1094 | && !pc_in_interrupt_handler (tmp_frame->pc)) |
| 1095 | return read_memory_integer (tmp_frame->frame, 4); |
| 1096 | /* %r3 was saved somewhere in the stack. Dig it out. */ |
| 1097 | else |
| 1098 | { |
| 1099 | struct frame_saved_regs saved_regs; |
| 1100 | |
| 1101 | /* Sick. |
| 1102 | |
| 1103 | For optimization purposes many kernels don't have the |
| 1104 | callee saved registers into the save_state structure upon |
| 1105 | entry into the kernel for a syscall; the optimization |
| 1106 | is usually turned off if the process is being traced so |
| 1107 | that the debugger can get full register state for the |
| 1108 | process. |
| 1109 | |
| 1110 | This scheme works well except for two cases: |
| 1111 | |
| 1112 | * Attaching to a process when the process is in the |
| 1113 | kernel performing a system call (debugger can't get |
| 1114 | full register state for the inferior process since |
| 1115 | the process wasn't being traced when it entered the |
| 1116 | system call). |
| 1117 | |
| 1118 | * Register state is not complete if the system call |
| 1119 | causes the process to core dump. |
| 1120 | |
| 1121 | |
| 1122 | The following heinous code is an attempt to deal with |
| 1123 | the lack of register state in a core dump. It will |
| 1124 | fail miserably if the function which performs the |
| 1125 | system call has a variable sized stack frame. */ |
| 1126 | |
| 1127 | get_frame_saved_regs (tmp_frame, &saved_regs); |
| 1128 | |
| 1129 | /* Abominable hack. */ |
| 1130 | if (current_target.to_has_execution == 0 |
| 1131 | && ((saved_regs.regs[FLAGS_REGNUM] |
| 1132 | && (read_memory_integer (saved_regs.regs[FLAGS_REGNUM], 4) |
| 1133 | & 0x2)) |
| 1134 | || (saved_regs.regs[FLAGS_REGNUM] == 0 |
| 1135 | && read_register (FLAGS_REGNUM) & 0x2))) |
| 1136 | { |
| 1137 | u = find_unwind_entry (FRAME_SAVED_PC (frame)); |
| 1138 | if (!u) |
| 1139 | return read_memory_integer (saved_regs.regs[FP_REGNUM], 4); |
| 1140 | else |
| 1141 | return frame_base - (u->Total_frame_size << 3); |
| 1142 | } |
| 1143 | |
| 1144 | return read_memory_integer (saved_regs.regs[FP_REGNUM], 4); |
| 1145 | } |
| 1146 | } |
| 1147 | else |
| 1148 | { |
| 1149 | struct frame_saved_regs saved_regs; |
| 1150 | |
| 1151 | /* Get the innermost frame. */ |
| 1152 | tmp_frame = frame; |
| 1153 | while (tmp_frame->next != NULL) |
| 1154 | tmp_frame = tmp_frame->next; |
| 1155 | |
| 1156 | get_frame_saved_regs (tmp_frame, &saved_regs); |
| 1157 | /* Abominable hack. See above. */ |
| 1158 | if (current_target.to_has_execution == 0 |
| 1159 | && ((saved_regs.regs[FLAGS_REGNUM] |
| 1160 | && (read_memory_integer (saved_regs.regs[FLAGS_REGNUM], 4) |
| 1161 | & 0x2)) |
| 1162 | || (saved_regs.regs[FLAGS_REGNUM] == 0 |
| 1163 | && read_register (FLAGS_REGNUM) & 0x2))) |
| 1164 | { |
| 1165 | u = find_unwind_entry (FRAME_SAVED_PC (frame)); |
| 1166 | if (!u) |
| 1167 | return read_memory_integer (saved_regs.regs[FP_REGNUM], 4); |
| 1168 | else |
| 1169 | return frame_base - (u->Total_frame_size << 3); |
| 1170 | } |
| 1171 | |
| 1172 | /* The value in %r3 was never saved into the stack (thus %r3 still |
| 1173 | holds the value of the previous frame pointer). */ |
| 1174 | return read_register (FP_REGNUM); |
| 1175 | } |
| 1176 | } |
| 1177 | |
| 1178 | \f |
| 1179 | /* To see if a frame chain is valid, see if the caller looks like it |
| 1180 | was compiled with gcc. */ |
| 1181 | |
| 1182 | int |
| 1183 | frame_chain_valid (chain, thisframe) |
| 1184 | CORE_ADDR chain; |
| 1185 | struct frame_info *thisframe; |
| 1186 | { |
| 1187 | struct minimal_symbol *msym_us; |
| 1188 | struct minimal_symbol *msym_start; |
| 1189 | struct unwind_table_entry *u, *next_u = NULL; |
| 1190 | struct frame_info *next; |
| 1191 | |
| 1192 | if (!chain) |
| 1193 | return 0; |
| 1194 | |
| 1195 | u = find_unwind_entry (thisframe->pc); |
| 1196 | |
| 1197 | if (u == NULL) |
| 1198 | return 1; |
| 1199 | |
| 1200 | /* We can't just check that the same of msym_us is "_start", because |
| 1201 | someone idiotically decided that they were going to make a Ltext_end |
| 1202 | symbol with the same address. This Ltext_end symbol is totally |
| 1203 | indistinguishable (as nearly as I can tell) from the symbol for a function |
| 1204 | which is (legitimately, since it is in the user's namespace) |
| 1205 | named Ltext_end, so we can't just ignore it. */ |
| 1206 | msym_us = lookup_minimal_symbol_by_pc (FRAME_SAVED_PC (thisframe)); |
| 1207 | msym_start = lookup_minimal_symbol ("_start", NULL, NULL); |
| 1208 | if (msym_us |
| 1209 | && msym_start |
| 1210 | && SYMBOL_VALUE_ADDRESS (msym_us) == SYMBOL_VALUE_ADDRESS (msym_start)) |
| 1211 | return 0; |
| 1212 | |
| 1213 | /* Grrrr. Some new idiot decided that they don't want _start for the |
| 1214 | PRO configurations; $START$ calls main directly.... Deal with it. */ |
| 1215 | msym_start = lookup_minimal_symbol ("$START$", NULL, NULL); |
| 1216 | if (msym_us |
| 1217 | && msym_start |
| 1218 | && SYMBOL_VALUE_ADDRESS (msym_us) == SYMBOL_VALUE_ADDRESS (msym_start)) |
| 1219 | return 0; |
| 1220 | |
| 1221 | next = get_next_frame (thisframe); |
| 1222 | if (next) |
| 1223 | next_u = find_unwind_entry (next->pc); |
| 1224 | |
| 1225 | /* If this frame does not save SP, has no stack, isn't a stub, |
| 1226 | and doesn't "call" an interrupt routine or signal handler caller, |
| 1227 | then its not valid. */ |
| 1228 | if (u->Save_SP || u->Total_frame_size || u->stub_type != 0 |
| 1229 | || (thisframe->next && thisframe->next->signal_handler_caller) |
| 1230 | || (next_u && next_u->HP_UX_interrupt_marker)) |
| 1231 | return 1; |
| 1232 | |
| 1233 | if (pc_in_linker_stub (thisframe->pc)) |
| 1234 | return 1; |
| 1235 | |
| 1236 | return 0; |
| 1237 | } |
| 1238 | |
| 1239 | /* |
| 1240 | * These functions deal with saving and restoring register state |
| 1241 | * around a function call in the inferior. They keep the stack |
| 1242 | * double-word aligned; eventually, on an hp700, the stack will have |
| 1243 | * to be aligned to a 64-byte boundary. |
| 1244 | */ |
| 1245 | |
| 1246 | void |
| 1247 | push_dummy_frame (inf_status) |
| 1248 | struct inferior_status *inf_status; |
| 1249 | { |
| 1250 | CORE_ADDR sp, pc, pcspace; |
| 1251 | register int regnum; |
| 1252 | int int_buffer; |
| 1253 | double freg_buffer; |
| 1254 | |
| 1255 | /* Oh, what a hack. If we're trying to perform an inferior call |
| 1256 | while the inferior is asleep, we have to make sure to clear |
| 1257 | the "in system call" bit in the flag register (the call will |
| 1258 | start after the syscall returns, so we're no longer in the system |
| 1259 | call!) This state is kept in "inf_status", change it there. |
| 1260 | |
| 1261 | We also need a number of horrid hacks to deal with lossage in the |
| 1262 | PC queue registers (apparently they're not valid when the in syscall |
| 1263 | bit is set). */ |
| 1264 | pc = target_read_pc (inferior_pid); |
| 1265 | int_buffer = read_register (FLAGS_REGNUM); |
| 1266 | if (int_buffer & 0x2) |
| 1267 | { |
| 1268 | unsigned int sid; |
| 1269 | int_buffer &= ~0x2; |
| 1270 | memcpy (inf_status->registers, &int_buffer, 4); |
| 1271 | memcpy (inf_status->registers + REGISTER_BYTE (PCOQ_HEAD_REGNUM), &pc, 4); |
| 1272 | pc += 4; |
| 1273 | memcpy (inf_status->registers + REGISTER_BYTE (PCOQ_TAIL_REGNUM), &pc, 4); |
| 1274 | pc -= 4; |
| 1275 | sid = (pc >> 30) & 0x3; |
| 1276 | if (sid == 0) |
| 1277 | pcspace = read_register (SR4_REGNUM); |
| 1278 | else |
| 1279 | pcspace = read_register (SR4_REGNUM + 4 + sid); |
| 1280 | memcpy (inf_status->registers + REGISTER_BYTE (PCSQ_HEAD_REGNUM), |
| 1281 | &pcspace, 4); |
| 1282 | memcpy (inf_status->registers + REGISTER_BYTE (PCSQ_TAIL_REGNUM), |
| 1283 | &pcspace, 4); |
| 1284 | } |
| 1285 | else |
| 1286 | pcspace = read_register (PCSQ_HEAD_REGNUM); |
| 1287 | |
| 1288 | /* Space for "arguments"; the RP goes in here. */ |
| 1289 | sp = read_register (SP_REGNUM) + 48; |
| 1290 | int_buffer = read_register (RP_REGNUM) | 0x3; |
| 1291 | write_memory (sp - 20, (char *)&int_buffer, 4); |
| 1292 | |
| 1293 | int_buffer = read_register (FP_REGNUM); |
| 1294 | write_memory (sp, (char *)&int_buffer, 4); |
| 1295 | |
| 1296 | write_register (FP_REGNUM, sp); |
| 1297 | |
| 1298 | sp += 8; |
| 1299 | |
| 1300 | for (regnum = 1; regnum < 32; regnum++) |
| 1301 | if (regnum != RP_REGNUM && regnum != FP_REGNUM) |
| 1302 | sp = push_word (sp, read_register (regnum)); |
| 1303 | |
| 1304 | sp += 4; |
| 1305 | |
| 1306 | for (regnum = FP0_REGNUM; regnum < NUM_REGS; regnum++) |
| 1307 | { |
| 1308 | read_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8); |
| 1309 | sp = push_bytes (sp, (char *)&freg_buffer, 8); |
| 1310 | } |
| 1311 | sp = push_word (sp, read_register (IPSW_REGNUM)); |
| 1312 | sp = push_word (sp, read_register (SAR_REGNUM)); |
| 1313 | sp = push_word (sp, pc); |
| 1314 | sp = push_word (sp, pcspace); |
| 1315 | sp = push_word (sp, pc + 4); |
| 1316 | sp = push_word (sp, pcspace); |
| 1317 | write_register (SP_REGNUM, sp); |
| 1318 | } |
| 1319 | |
| 1320 | static void |
| 1321 | find_dummy_frame_regs (frame, frame_saved_regs) |
| 1322 | struct frame_info *frame; |
| 1323 | struct frame_saved_regs *frame_saved_regs; |
| 1324 | { |
| 1325 | CORE_ADDR fp = frame->frame; |
| 1326 | int i; |
| 1327 | |
| 1328 | frame_saved_regs->regs[RP_REGNUM] = (fp - 20) & ~0x3; |
| 1329 | frame_saved_regs->regs[FP_REGNUM] = fp; |
| 1330 | frame_saved_regs->regs[1] = fp + 8; |
| 1331 | |
| 1332 | for (fp += 12, i = 3; i < 32; i++) |
| 1333 | { |
| 1334 | if (i != FP_REGNUM) |
| 1335 | { |
| 1336 | frame_saved_regs->regs[i] = fp; |
| 1337 | fp += 4; |
| 1338 | } |
| 1339 | } |
| 1340 | |
| 1341 | fp += 4; |
| 1342 | for (i = FP0_REGNUM; i < NUM_REGS; i++, fp += 8) |
| 1343 | frame_saved_regs->regs[i] = fp; |
| 1344 | |
| 1345 | frame_saved_regs->regs[IPSW_REGNUM] = fp; |
| 1346 | frame_saved_regs->regs[SAR_REGNUM] = fp + 4; |
| 1347 | frame_saved_regs->regs[PCOQ_HEAD_REGNUM] = fp + 8; |
| 1348 | frame_saved_regs->regs[PCSQ_HEAD_REGNUM] = fp + 12; |
| 1349 | frame_saved_regs->regs[PCOQ_TAIL_REGNUM] = fp + 16; |
| 1350 | frame_saved_regs->regs[PCSQ_TAIL_REGNUM] = fp + 20; |
| 1351 | } |
| 1352 | |
| 1353 | void |
| 1354 | hppa_pop_frame () |
| 1355 | { |
| 1356 | register struct frame_info *frame = get_current_frame (); |
| 1357 | register CORE_ADDR fp, npc, target_pc; |
| 1358 | register int regnum; |
| 1359 | struct frame_saved_regs fsr; |
| 1360 | double freg_buffer; |
| 1361 | |
| 1362 | fp = FRAME_FP (frame); |
| 1363 | get_frame_saved_regs (frame, &fsr); |
| 1364 | |
| 1365 | #ifndef NO_PC_SPACE_QUEUE_RESTORE |
| 1366 | if (fsr.regs[IPSW_REGNUM]) /* Restoring a call dummy frame */ |
| 1367 | restore_pc_queue (&fsr); |
| 1368 | #endif |
| 1369 | |
| 1370 | for (regnum = 31; regnum > 0; regnum--) |
| 1371 | if (fsr.regs[regnum]) |
| 1372 | write_register (regnum, read_memory_integer (fsr.regs[regnum], 4)); |
| 1373 | |
| 1374 | for (regnum = NUM_REGS - 1; regnum >= FP0_REGNUM ; regnum--) |
| 1375 | if (fsr.regs[regnum]) |
| 1376 | { |
| 1377 | read_memory (fsr.regs[regnum], (char *)&freg_buffer, 8); |
| 1378 | write_register_bytes (REGISTER_BYTE (regnum), (char *)&freg_buffer, 8); |
| 1379 | } |
| 1380 | |
| 1381 | if (fsr.regs[IPSW_REGNUM]) |
| 1382 | write_register (IPSW_REGNUM, |
| 1383 | read_memory_integer (fsr.regs[IPSW_REGNUM], 4)); |
| 1384 | |
| 1385 | if (fsr.regs[SAR_REGNUM]) |
| 1386 | write_register (SAR_REGNUM, |
| 1387 | read_memory_integer (fsr.regs[SAR_REGNUM], 4)); |
| 1388 | |
| 1389 | /* If the PC was explicitly saved, then just restore it. */ |
| 1390 | if (fsr.regs[PCOQ_TAIL_REGNUM]) |
| 1391 | { |
| 1392 | npc = read_memory_integer (fsr.regs[PCOQ_TAIL_REGNUM], 4); |
| 1393 | write_register (PCOQ_TAIL_REGNUM, npc); |
| 1394 | } |
| 1395 | /* Else use the value in %rp to set the new PC. */ |
| 1396 | else |
| 1397 | { |
| 1398 | npc = read_register (RP_REGNUM); |
| 1399 | target_write_pc (npc, 0); |
| 1400 | } |
| 1401 | |
| 1402 | write_register (FP_REGNUM, read_memory_integer (fp, 4)); |
| 1403 | |
| 1404 | if (fsr.regs[IPSW_REGNUM]) /* call dummy */ |
| 1405 | write_register (SP_REGNUM, fp - 48); |
| 1406 | else |
| 1407 | write_register (SP_REGNUM, fp); |
| 1408 | |
| 1409 | /* The PC we just restored may be inside a return trampoline. If so |
| 1410 | we want to restart the inferior and run it through the trampoline. |
| 1411 | |
| 1412 | Do this by setting a momentary breakpoint at the location the |
| 1413 | trampoline returns to. |
| 1414 | |
| 1415 | Don't skip through the trampoline if we're popping a dummy frame. */ |
| 1416 | target_pc = SKIP_TRAMPOLINE_CODE (npc & ~0x3) & ~0x3; |
| 1417 | if (target_pc && !fsr.regs[IPSW_REGNUM]) |
| 1418 | { |
| 1419 | struct symtab_and_line sal; |
| 1420 | struct breakpoint *breakpoint; |
| 1421 | struct cleanup *old_chain; |
| 1422 | |
| 1423 | /* Set up our breakpoint. Set it to be silent as the MI code |
| 1424 | for "return_command" will print the frame we returned to. */ |
| 1425 | sal = find_pc_line (target_pc, 0); |
| 1426 | sal.pc = target_pc; |
| 1427 | breakpoint = set_momentary_breakpoint (sal, NULL, bp_finish); |
| 1428 | breakpoint->silent = 1; |
| 1429 | |
| 1430 | /* So we can clean things up. */ |
| 1431 | old_chain = make_cleanup (delete_breakpoint, breakpoint); |
| 1432 | |
| 1433 | /* Start up the inferior. */ |
| 1434 | clear_proceed_status (); |
| 1435 | proceed_to_finish = 1; |
| 1436 | proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0); |
| 1437 | |
| 1438 | /* Perform our cleanups. */ |
| 1439 | do_cleanups (old_chain); |
| 1440 | } |
| 1441 | flush_cached_frames (); |
| 1442 | } |
| 1443 | |
| 1444 | /* |
| 1445 | * After returning to a dummy on the stack, restore the instruction |
| 1446 | * queue space registers. */ |
| 1447 | |
| 1448 | static int |
| 1449 | restore_pc_queue (fsr) |
| 1450 | struct frame_saved_regs *fsr; |
| 1451 | { |
| 1452 | CORE_ADDR pc = read_pc (); |
| 1453 | CORE_ADDR new_pc = read_memory_integer (fsr->regs[PCOQ_HEAD_REGNUM], 4); |
| 1454 | struct target_waitstatus w; |
| 1455 | int insn_count; |
| 1456 | |
| 1457 | /* Advance past break instruction in the call dummy. */ |
| 1458 | write_register (PCOQ_HEAD_REGNUM, pc + 4); |
| 1459 | write_register (PCOQ_TAIL_REGNUM, pc + 8); |
| 1460 | |
| 1461 | /* |
| 1462 | * HPUX doesn't let us set the space registers or the space |
| 1463 | * registers of the PC queue through ptrace. Boo, hiss. |
| 1464 | * Conveniently, the call dummy has this sequence of instructions |
| 1465 | * after the break: |
| 1466 | * mtsp r21, sr0 |
| 1467 | * ble,n 0(sr0, r22) |
| 1468 | * |
| 1469 | * So, load up the registers and single step until we are in the |
| 1470 | * right place. |
| 1471 | */ |
| 1472 | |
| 1473 | write_register (21, read_memory_integer (fsr->regs[PCSQ_HEAD_REGNUM], 4)); |
| 1474 | write_register (22, new_pc); |
| 1475 | |
| 1476 | for (insn_count = 0; insn_count < 3; insn_count++) |
| 1477 | { |
| 1478 | /* FIXME: What if the inferior gets a signal right now? Want to |
| 1479 | merge this into wait_for_inferior (as a special kind of |
| 1480 | watchpoint? By setting a breakpoint at the end? Is there |
| 1481 | any other choice? Is there *any* way to do this stuff with |
| 1482 | ptrace() or some equivalent?). */ |
| 1483 | resume (1, 0); |
| 1484 | target_wait (inferior_pid, &w); |
| 1485 | |
| 1486 | if (w.kind == TARGET_WAITKIND_SIGNALLED) |
| 1487 | { |
| 1488 | stop_signal = w.value.sig; |
| 1489 | terminal_ours_for_output (); |
| 1490 | printf_unfiltered ("\nProgram terminated with signal %s, %s.\n", |
| 1491 | target_signal_to_name (stop_signal), |
| 1492 | target_signal_to_string (stop_signal)); |
| 1493 | gdb_flush (gdb_stdout); |
| 1494 | return 0; |
| 1495 | } |
| 1496 | } |
| 1497 | target_terminal_ours (); |
| 1498 | target_fetch_registers (-1); |
| 1499 | return 1; |
| 1500 | } |
| 1501 | |
| 1502 | CORE_ADDR |
| 1503 | hppa_push_arguments (nargs, args, sp, struct_return, struct_addr) |
| 1504 | int nargs; |
| 1505 | value_ptr *args; |
| 1506 | CORE_ADDR sp; |
| 1507 | int struct_return; |
| 1508 | CORE_ADDR struct_addr; |
| 1509 | { |
| 1510 | /* array of arguments' offsets */ |
| 1511 | int *offset = (int *)alloca(nargs * sizeof (int)); |
| 1512 | int cum = 0; |
| 1513 | int i, alignment; |
| 1514 | |
| 1515 | for (i = 0; i < nargs; i++) |
| 1516 | { |
| 1517 | cum += TYPE_LENGTH (VALUE_TYPE (args[i])); |
| 1518 | |
| 1519 | /* value must go at proper alignment. Assume alignment is a |
| 1520 | power of two.*/ |
| 1521 | alignment = hppa_alignof (VALUE_TYPE (args[i])); |
| 1522 | if (cum % alignment) |
| 1523 | cum = (cum + alignment) & -alignment; |
| 1524 | offset[i] = -cum; |
| 1525 | } |
| 1526 | sp += max ((cum + 7) & -8, 16); |
| 1527 | |
| 1528 | for (i = 0; i < nargs; i++) |
| 1529 | write_memory (sp + offset[i], VALUE_CONTENTS (args[i]), |
| 1530 | TYPE_LENGTH (VALUE_TYPE (args[i]))); |
| 1531 | |
| 1532 | if (struct_return) |
| 1533 | write_register (28, struct_addr); |
| 1534 | return sp + 32; |
| 1535 | } |
| 1536 | |
| 1537 | /* |
| 1538 | * Insert the specified number of args and function address |
| 1539 | * into a call sequence of the above form stored at DUMMYNAME. |
| 1540 | * |
| 1541 | * On the hppa we need to call the stack dummy through $$dyncall. |
| 1542 | * Therefore our version of FIX_CALL_DUMMY takes an extra argument, |
| 1543 | * real_pc, which is the location where gdb should start up the |
| 1544 | * inferior to do the function call. |
| 1545 | */ |
| 1546 | |
| 1547 | CORE_ADDR |
| 1548 | hppa_fix_call_dummy (dummy, pc, fun, nargs, args, type, gcc_p) |
| 1549 | char *dummy; |
| 1550 | CORE_ADDR pc; |
| 1551 | CORE_ADDR fun; |
| 1552 | int nargs; |
| 1553 | value_ptr *args; |
| 1554 | struct type *type; |
| 1555 | int gcc_p; |
| 1556 | { |
| 1557 | CORE_ADDR dyncall_addr; |
| 1558 | struct minimal_symbol *msymbol; |
| 1559 | struct minimal_symbol *trampoline; |
| 1560 | int flags = read_register (FLAGS_REGNUM); |
| 1561 | struct unwind_table_entry *u; |
| 1562 | |
| 1563 | trampoline = NULL; |
| 1564 | msymbol = lookup_minimal_symbol ("$$dyncall", NULL, NULL); |
| 1565 | if (msymbol == NULL) |
| 1566 | error ("Can't find an address for $$dyncall trampoline"); |
| 1567 | |
| 1568 | dyncall_addr = SYMBOL_VALUE_ADDRESS (msymbol); |
| 1569 | |
| 1570 | /* FUN could be a procedure label, in which case we have to get |
| 1571 | its real address and the value of its GOT/DP. */ |
| 1572 | if (fun & 0x2) |
| 1573 | { |
| 1574 | /* Get the GOT/DP value for the target function. It's |
| 1575 | at *(fun+4). Note the call dummy is *NOT* allowed to |
| 1576 | trash %r19 before calling the target function. */ |
| 1577 | write_register (19, read_memory_integer ((fun & ~0x3) + 4, 4)); |
| 1578 | |
| 1579 | /* Now get the real address for the function we are calling, it's |
| 1580 | at *fun. */ |
| 1581 | fun = (CORE_ADDR) read_memory_integer (fun & ~0x3, 4); |
| 1582 | } |
| 1583 | else |
| 1584 | { |
| 1585 | |
| 1586 | #ifndef GDB_TARGET_IS_PA_ELF |
| 1587 | /* FUN could be either an export stub, or the real address of a |
| 1588 | function in a shared library. We must call an import stub |
| 1589 | rather than the export stub or real function for lazy binding |
| 1590 | to work correctly. */ |
| 1591 | if (som_solib_get_got_by_pc (fun)) |
| 1592 | { |
| 1593 | struct objfile *objfile; |
| 1594 | struct minimal_symbol *funsymbol, *stub_symbol; |
| 1595 | CORE_ADDR newfun = 0; |
| 1596 | |
| 1597 | funsymbol = lookup_minimal_symbol_by_pc (fun); |
| 1598 | if (!funsymbol) |
| 1599 | error ("Unable to find minimal symbol for target fucntion.\n"); |
| 1600 | |
| 1601 | /* Search all the object files for an import symbol with the |
| 1602 | right name. */ |
| 1603 | ALL_OBJFILES (objfile) |
| 1604 | { |
| 1605 | stub_symbol = lookup_minimal_symbol (SYMBOL_NAME (funsymbol), |
| 1606 | NULL, objfile); |
| 1607 | /* Found a symbol with the right name. */ |
| 1608 | if (stub_symbol) |
| 1609 | { |
| 1610 | struct unwind_table_entry *u; |
| 1611 | /* It must be a shared library trampoline. */ |
| 1612 | if (SYMBOL_TYPE (stub_symbol) != mst_solib_trampoline) |
| 1613 | continue; |
| 1614 | |
| 1615 | /* It must also be an import stub. */ |
| 1616 | u = find_unwind_entry (SYMBOL_VALUE (stub_symbol)); |
| 1617 | if (!u || u->stub_type != IMPORT) |
| 1618 | continue; |
| 1619 | |
| 1620 | /* OK. Looks like the correct import stub. */ |
| 1621 | newfun = SYMBOL_VALUE (stub_symbol); |
| 1622 | fun = newfun; |
| 1623 | } |
| 1624 | } |
| 1625 | if (newfun == 0) |
| 1626 | write_register (19, som_solib_get_got_by_pc (fun)); |
| 1627 | } |
| 1628 | #endif |
| 1629 | } |
| 1630 | |
| 1631 | /* If we are calling an import stub (eg calling into a dynamic library) |
| 1632 | then have sr4export call the magic __d_plt_call routine which is linked |
| 1633 | in from end.o. (You can't use _sr4export to call the import stub as |
| 1634 | the value in sp-24 will get fried and you end up returning to the |
| 1635 | wrong location. You can't call the import stub directly as the code |
| 1636 | to bind the PLT entry to a function can't return to a stack address.) */ |
| 1637 | u = find_unwind_entry (fun); |
| 1638 | if (u && u->stub_type == IMPORT) |
| 1639 | { |
| 1640 | CORE_ADDR new_fun; |
| 1641 | |
| 1642 | /* Prefer __gcc_plt_call over the HP supplied routine because |
| 1643 | __gcc_plt_call works for any number of arguments. */ |
| 1644 | trampoline = lookup_minimal_symbol ("__gcc_plt_call", NULL, NULL); |
| 1645 | if (trampoline == NULL) |
| 1646 | trampoline = lookup_minimal_symbol ("__d_plt_call", NULL, NULL); |
| 1647 | |
| 1648 | if (trampoline == NULL) |
| 1649 | error ("Can't find an address for __d_plt_call or __gcc_plt_call trampoline"); |
| 1650 | |
| 1651 | /* This is where sr4export will jump to. */ |
| 1652 | new_fun = SYMBOL_VALUE_ADDRESS (trampoline); |
| 1653 | |
| 1654 | if (strcmp (SYMBOL_NAME (trampoline), "__d_plt_call") == 0) |
| 1655 | { |
| 1656 | /* We have to store the address of the stub in __shlib_funcptr. */ |
| 1657 | msymbol = lookup_minimal_symbol ("__shlib_funcptr", NULL, |
| 1658 | (struct objfile *)NULL); |
| 1659 | if (msymbol == NULL) |
| 1660 | error ("Can't find an address for __shlib_funcptr"); |
| 1661 | |
| 1662 | target_write_memory (SYMBOL_VALUE_ADDRESS (msymbol), (char *)&fun, 4); |
| 1663 | |
| 1664 | /* We want sr4export to call __d_plt_call, so we claim it is |
| 1665 | the final target. Clear trampoline. */ |
| 1666 | fun = new_fun; |
| 1667 | trampoline = NULL; |
| 1668 | } |
| 1669 | } |
| 1670 | |
| 1671 | /* Store upper 21 bits of function address into ldil. fun will either be |
| 1672 | the final target (most cases) or __d_plt_call when calling into a shared |
| 1673 | library and __gcc_plt_call is not available. */ |
| 1674 | store_unsigned_integer |
| 1675 | (&dummy[FUNC_LDIL_OFFSET], |
| 1676 | INSTRUCTION_SIZE, |
| 1677 | deposit_21 (fun >> 11, |
| 1678 | extract_unsigned_integer (&dummy[FUNC_LDIL_OFFSET], |
| 1679 | INSTRUCTION_SIZE))); |
| 1680 | |
| 1681 | /* Store lower 11 bits of function address into ldo */ |
| 1682 | store_unsigned_integer |
| 1683 | (&dummy[FUNC_LDO_OFFSET], |
| 1684 | INSTRUCTION_SIZE, |
| 1685 | deposit_14 (fun & MASK_11, |
| 1686 | extract_unsigned_integer (&dummy[FUNC_LDO_OFFSET], |
| 1687 | INSTRUCTION_SIZE))); |
| 1688 | #ifdef SR4EXPORT_LDIL_OFFSET |
| 1689 | |
| 1690 | { |
| 1691 | CORE_ADDR trampoline_addr; |
| 1692 | |
| 1693 | /* We may still need sr4export's address too. */ |
| 1694 | |
| 1695 | if (trampoline == NULL) |
| 1696 | { |
| 1697 | msymbol = lookup_minimal_symbol ("_sr4export", NULL, NULL); |
| 1698 | if (msymbol == NULL) |
| 1699 | error ("Can't find an address for _sr4export trampoline"); |
| 1700 | |
| 1701 | trampoline_addr = SYMBOL_VALUE_ADDRESS (msymbol); |
| 1702 | } |
| 1703 | else |
| 1704 | trampoline_addr = SYMBOL_VALUE_ADDRESS (trampoline); |
| 1705 | |
| 1706 | |
| 1707 | /* Store upper 21 bits of trampoline's address into ldil */ |
| 1708 | store_unsigned_integer |
| 1709 | (&dummy[SR4EXPORT_LDIL_OFFSET], |
| 1710 | INSTRUCTION_SIZE, |
| 1711 | deposit_21 (trampoline_addr >> 11, |
| 1712 | extract_unsigned_integer (&dummy[SR4EXPORT_LDIL_OFFSET], |
| 1713 | INSTRUCTION_SIZE))); |
| 1714 | |
| 1715 | /* Store lower 11 bits of trampoline's address into ldo */ |
| 1716 | store_unsigned_integer |
| 1717 | (&dummy[SR4EXPORT_LDO_OFFSET], |
| 1718 | INSTRUCTION_SIZE, |
| 1719 | deposit_14 (trampoline_addr & MASK_11, |
| 1720 | extract_unsigned_integer (&dummy[SR4EXPORT_LDO_OFFSET], |
| 1721 | INSTRUCTION_SIZE))); |
| 1722 | } |
| 1723 | #endif |
| 1724 | |
| 1725 | write_register (22, pc); |
| 1726 | |
| 1727 | /* If we are in a syscall, then we should call the stack dummy |
| 1728 | directly. $$dyncall is not needed as the kernel sets up the |
| 1729 | space id registers properly based on the value in %r31. In |
| 1730 | fact calling $$dyncall will not work because the value in %r22 |
| 1731 | will be clobbered on the syscall exit path. |
| 1732 | |
| 1733 | Similarly if the current PC is in a shared library. Note however, |
| 1734 | this scheme won't work if the shared library isn't mapped into |
| 1735 | the same space as the stack. */ |
| 1736 | if (flags & 2) |
| 1737 | return pc; |
| 1738 | #ifndef GDB_TARGET_IS_PA_ELF |
| 1739 | else if (som_solib_get_got_by_pc (target_read_pc (inferior_pid))) |
| 1740 | return pc; |
| 1741 | #endif |
| 1742 | else |
| 1743 | return dyncall_addr; |
| 1744 | |
| 1745 | } |
| 1746 | |
| 1747 | /* Get the PC from %r31 if currently in a syscall. Also mask out privilege |
| 1748 | bits. */ |
| 1749 | |
| 1750 | CORE_ADDR |
| 1751 | target_read_pc (pid) |
| 1752 | int pid; |
| 1753 | { |
| 1754 | int flags = read_register (FLAGS_REGNUM); |
| 1755 | |
| 1756 | if (flags & 2) { |
| 1757 | return read_register (31) & ~0x3; |
| 1758 | } |
| 1759 | return read_register (PC_REGNUM) & ~0x3; |
| 1760 | } |
| 1761 | |
| 1762 | /* Write out the PC. If currently in a syscall, then also write the new |
| 1763 | PC value into %r31. */ |
| 1764 | |
| 1765 | void |
| 1766 | target_write_pc (v, pid) |
| 1767 | CORE_ADDR v; |
| 1768 | int pid; |
| 1769 | { |
| 1770 | int flags = read_register (FLAGS_REGNUM); |
| 1771 | |
| 1772 | /* If in a syscall, then set %r31. Also make sure to get the |
| 1773 | privilege bits set correctly. */ |
| 1774 | if (flags & 2) |
| 1775 | write_register (31, (long) (v | 0x3)); |
| 1776 | |
| 1777 | write_register (PC_REGNUM, (long) v); |
| 1778 | write_register (NPC_REGNUM, (long) v + 4); |
| 1779 | } |
| 1780 | |
| 1781 | /* return the alignment of a type in bytes. Structures have the maximum |
| 1782 | alignment required by their fields. */ |
| 1783 | |
| 1784 | static int |
| 1785 | hppa_alignof (type) |
| 1786 | struct type *type; |
| 1787 | { |
| 1788 | int max_align, align, i; |
| 1789 | CHECK_TYPEDEF (type); |
| 1790 | switch (TYPE_CODE (type)) |
| 1791 | { |
| 1792 | case TYPE_CODE_PTR: |
| 1793 | case TYPE_CODE_INT: |
| 1794 | case TYPE_CODE_FLT: |
| 1795 | return TYPE_LENGTH (type); |
| 1796 | case TYPE_CODE_ARRAY: |
| 1797 | return hppa_alignof (TYPE_FIELD_TYPE (type, 0)); |
| 1798 | case TYPE_CODE_STRUCT: |
| 1799 | case TYPE_CODE_UNION: |
| 1800 | max_align = 2; |
| 1801 | for (i = 0; i < TYPE_NFIELDS (type); i++) |
| 1802 | { |
| 1803 | /* Bit fields have no real alignment. */ |
| 1804 | if (!TYPE_FIELD_BITPOS (type, i)) |
| 1805 | { |
| 1806 | align = hppa_alignof (TYPE_FIELD_TYPE (type, i)); |
| 1807 | max_align = max (max_align, align); |
| 1808 | } |
| 1809 | } |
| 1810 | return max_align; |
| 1811 | default: |
| 1812 | return 4; |
| 1813 | } |
| 1814 | } |
| 1815 | |
| 1816 | /* Print the register regnum, or all registers if regnum is -1 */ |
| 1817 | |
| 1818 | void |
| 1819 | pa_do_registers_info (regnum, fpregs) |
| 1820 | int regnum; |
| 1821 | int fpregs; |
| 1822 | { |
| 1823 | char raw_regs [REGISTER_BYTES]; |
| 1824 | int i; |
| 1825 | |
| 1826 | for (i = 0; i < NUM_REGS; i++) |
| 1827 | read_relative_register_raw_bytes (i, raw_regs + REGISTER_BYTE (i)); |
| 1828 | if (regnum == -1) |
| 1829 | pa_print_registers (raw_regs, regnum, fpregs); |
| 1830 | else if (regnum < FP0_REGNUM) |
| 1831 | printf_unfiltered ("%s %x\n", reg_names[regnum], *(long *)(raw_regs + |
| 1832 | REGISTER_BYTE (regnum))); |
| 1833 | else |
| 1834 | pa_print_fp_reg (regnum); |
| 1835 | } |
| 1836 | |
| 1837 | static void |
| 1838 | pa_print_registers (raw_regs, regnum, fpregs) |
| 1839 | char *raw_regs; |
| 1840 | int regnum; |
| 1841 | int fpregs; |
| 1842 | { |
| 1843 | int i,j; |
| 1844 | long val; |
| 1845 | |
| 1846 | for (i = 0; i < 18; i++) |
| 1847 | { |
| 1848 | for (j = 0; j < 4; j++) |
| 1849 | { |
| 1850 | val = |
| 1851 | extract_signed_integer (raw_regs + REGISTER_BYTE (i+(j*18)), 4); |
| 1852 | printf_unfiltered ("%8.8s: %8x ", reg_names[i+(j*18)], val); |
| 1853 | } |
| 1854 | printf_unfiltered ("\n"); |
| 1855 | } |
| 1856 | |
| 1857 | if (fpregs) |
| 1858 | for (i = 72; i < NUM_REGS; i++) |
| 1859 | pa_print_fp_reg (i); |
| 1860 | } |
| 1861 | |
| 1862 | static void |
| 1863 | pa_print_fp_reg (i) |
| 1864 | int i; |
| 1865 | { |
| 1866 | unsigned char raw_buffer[MAX_REGISTER_RAW_SIZE]; |
| 1867 | unsigned char virtual_buffer[MAX_REGISTER_VIRTUAL_SIZE]; |
| 1868 | |
| 1869 | /* Get 32bits of data. */ |
| 1870 | read_relative_register_raw_bytes (i, raw_buffer); |
| 1871 | |
| 1872 | /* Put it in the buffer. No conversions are ever necessary. */ |
| 1873 | memcpy (virtual_buffer, raw_buffer, REGISTER_RAW_SIZE (i)); |
| 1874 | |
| 1875 | fputs_filtered (reg_names[i], gdb_stdout); |
| 1876 | print_spaces_filtered (8 - strlen (reg_names[i]), gdb_stdout); |
| 1877 | fputs_filtered ("(single precision) ", gdb_stdout); |
| 1878 | |
| 1879 | val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, gdb_stdout, 0, |
| 1880 | 1, 0, Val_pretty_default); |
| 1881 | printf_filtered ("\n"); |
| 1882 | |
| 1883 | /* If "i" is even, then this register can also be a double-precision |
| 1884 | FP register. Dump it out as such. */ |
| 1885 | if ((i % 2) == 0) |
| 1886 | { |
| 1887 | /* Get the data in raw format for the 2nd half. */ |
| 1888 | read_relative_register_raw_bytes (i + 1, raw_buffer); |
| 1889 | |
| 1890 | /* Copy it into the appropriate part of the virtual buffer. */ |
| 1891 | memcpy (virtual_buffer + REGISTER_RAW_SIZE (i), raw_buffer, |
| 1892 | REGISTER_RAW_SIZE (i)); |
| 1893 | |
| 1894 | /* Dump it as a double. */ |
| 1895 | fputs_filtered (reg_names[i], gdb_stdout); |
| 1896 | print_spaces_filtered (8 - strlen (reg_names[i]), gdb_stdout); |
| 1897 | fputs_filtered ("(double precision) ", gdb_stdout); |
| 1898 | |
| 1899 | val_print (builtin_type_double, virtual_buffer, 0, gdb_stdout, 0, |
| 1900 | 1, 0, Val_pretty_default); |
| 1901 | printf_filtered ("\n"); |
| 1902 | } |
| 1903 | } |
| 1904 | |
| 1905 | /* Return one if PC is in the call path of a trampoline, else return zero. |
| 1906 | |
| 1907 | Note we return one for *any* call trampoline (long-call, arg-reloc), not |
| 1908 | just shared library trampolines (import, export). */ |
| 1909 | |
| 1910 | int |
| 1911 | in_solib_call_trampoline (pc, name) |
| 1912 | CORE_ADDR pc; |
| 1913 | char *name; |
| 1914 | { |
| 1915 | struct minimal_symbol *minsym; |
| 1916 | struct unwind_table_entry *u; |
| 1917 | static CORE_ADDR dyncall = 0; |
| 1918 | static CORE_ADDR sr4export = 0; |
| 1919 | |
| 1920 | /* FIXME XXX - dyncall and sr4export must be initialized whenever we get a |
| 1921 | new exec file */ |
| 1922 | |
| 1923 | /* First see if PC is in one of the two C-library trampolines. */ |
| 1924 | if (!dyncall) |
| 1925 | { |
| 1926 | minsym = lookup_minimal_symbol ("$$dyncall", NULL, NULL); |
| 1927 | if (minsym) |
| 1928 | dyncall = SYMBOL_VALUE_ADDRESS (minsym); |
| 1929 | else |
| 1930 | dyncall = -1; |
| 1931 | } |
| 1932 | |
| 1933 | if (!sr4export) |
| 1934 | { |
| 1935 | minsym = lookup_minimal_symbol ("_sr4export", NULL, NULL); |
| 1936 | if (minsym) |
| 1937 | sr4export = SYMBOL_VALUE_ADDRESS (minsym); |
| 1938 | else |
| 1939 | sr4export = -1; |
| 1940 | } |
| 1941 | |
| 1942 | if (pc == dyncall || pc == sr4export) |
| 1943 | return 1; |
| 1944 | |
| 1945 | /* Get the unwind descriptor corresponding to PC, return zero |
| 1946 | if no unwind was found. */ |
| 1947 | u = find_unwind_entry (pc); |
| 1948 | if (!u) |
| 1949 | return 0; |
| 1950 | |
| 1951 | /* If this isn't a linker stub, then return now. */ |
| 1952 | if (u->stub_type == 0) |
| 1953 | return 0; |
| 1954 | |
| 1955 | /* By definition a long-branch stub is a call stub. */ |
| 1956 | if (u->stub_type == LONG_BRANCH) |
| 1957 | return 1; |
| 1958 | |
| 1959 | /* The call and return path execute the same instructions within |
| 1960 | an IMPORT stub! So an IMPORT stub is both a call and return |
| 1961 | trampoline. */ |
| 1962 | if (u->stub_type == IMPORT) |
| 1963 | return 1; |
| 1964 | |
| 1965 | /* Parameter relocation stubs always have a call path and may have a |
| 1966 | return path. */ |
| 1967 | if (u->stub_type == PARAMETER_RELOCATION |
| 1968 | || u->stub_type == EXPORT) |
| 1969 | { |
| 1970 | CORE_ADDR addr; |
| 1971 | |
| 1972 | /* Search forward from the current PC until we hit a branch |
| 1973 | or the end of the stub. */ |
| 1974 | for (addr = pc; addr <= u->region_end; addr += 4) |
| 1975 | { |
| 1976 | unsigned long insn; |
| 1977 | |
| 1978 | insn = read_memory_integer (addr, 4); |
| 1979 | |
| 1980 | /* Does it look like a bl? If so then it's the call path, if |
| 1981 | we find a bv or be first, then we're on the return path. */ |
| 1982 | if ((insn & 0xfc00e000) == 0xe8000000) |
| 1983 | return 1; |
| 1984 | else if ((insn & 0xfc00e001) == 0xe800c000 |
| 1985 | || (insn & 0xfc000000) == 0xe0000000) |
| 1986 | return 0; |
| 1987 | } |
| 1988 | |
| 1989 | /* Should never happen. */ |
| 1990 | warning ("Unable to find branch in parameter relocation stub.\n"); |
| 1991 | return 0; |
| 1992 | } |
| 1993 | |
| 1994 | /* Unknown stub type. For now, just return zero. */ |
| 1995 | return 0; |
| 1996 | } |
| 1997 | |
| 1998 | /* Return one if PC is in the return path of a trampoline, else return zero. |
| 1999 | |
| 2000 | Note we return one for *any* call trampoline (long-call, arg-reloc), not |
| 2001 | just shared library trampolines (import, export). */ |
| 2002 | |
| 2003 | int |
| 2004 | in_solib_return_trampoline (pc, name) |
| 2005 | CORE_ADDR pc; |
| 2006 | char *name; |
| 2007 | { |
| 2008 | struct unwind_table_entry *u; |
| 2009 | |
| 2010 | /* Get the unwind descriptor corresponding to PC, return zero |
| 2011 | if no unwind was found. */ |
| 2012 | u = find_unwind_entry (pc); |
| 2013 | if (!u) |
| 2014 | return 0; |
| 2015 | |
| 2016 | /* If this isn't a linker stub or it's just a long branch stub, then |
| 2017 | return zero. */ |
| 2018 | if (u->stub_type == 0 || u->stub_type == LONG_BRANCH) |
| 2019 | return 0; |
| 2020 | |
| 2021 | /* The call and return path execute the same instructions within |
| 2022 | an IMPORT stub! So an IMPORT stub is both a call and return |
| 2023 | trampoline. */ |
| 2024 | if (u->stub_type == IMPORT) |
| 2025 | return 1; |
| 2026 | |
| 2027 | /* Parameter relocation stubs always have a call path and may have a |
| 2028 | return path. */ |
| 2029 | if (u->stub_type == PARAMETER_RELOCATION |
| 2030 | || u->stub_type == EXPORT) |
| 2031 | { |
| 2032 | CORE_ADDR addr; |
| 2033 | |
| 2034 | /* Search forward from the current PC until we hit a branch |
| 2035 | or the end of the stub. */ |
| 2036 | for (addr = pc; addr <= u->region_end; addr += 4) |
| 2037 | { |
| 2038 | unsigned long insn; |
| 2039 | |
| 2040 | insn = read_memory_integer (addr, 4); |
| 2041 | |
| 2042 | /* Does it look like a bl? If so then it's the call path, if |
| 2043 | we find a bv or be first, then we're on the return path. */ |
| 2044 | if ((insn & 0xfc00e000) == 0xe8000000) |
| 2045 | return 0; |
| 2046 | else if ((insn & 0xfc00e001) == 0xe800c000 |
| 2047 | || (insn & 0xfc000000) == 0xe0000000) |
| 2048 | return 1; |
| 2049 | } |
| 2050 | |
| 2051 | /* Should never happen. */ |
| 2052 | warning ("Unable to find branch in parameter relocation stub.\n"); |
| 2053 | return 0; |
| 2054 | } |
| 2055 | |
| 2056 | /* Unknown stub type. For now, just return zero. */ |
| 2057 | return 0; |
| 2058 | |
| 2059 | } |
| 2060 | |
| 2061 | /* Figure out if PC is in a trampoline, and if so find out where |
| 2062 | the trampoline will jump to. If not in a trampoline, return zero. |
| 2063 | |
| 2064 | Simple code examination probably is not a good idea since the code |
| 2065 | sequences in trampolines can also appear in user code. |
| 2066 | |
| 2067 | We use unwinds and information from the minimal symbol table to |
| 2068 | determine when we're in a trampoline. This won't work for ELF |
| 2069 | (yet) since it doesn't create stub unwind entries. Whether or |
| 2070 | not ELF will create stub unwinds or normal unwinds for linker |
| 2071 | stubs is still being debated. |
| 2072 | |
| 2073 | This should handle simple calls through dyncall or sr4export, |
| 2074 | long calls, argument relocation stubs, and dyncall/sr4export |
| 2075 | calling an argument relocation stub. It even handles some stubs |
| 2076 | used in dynamic executables. */ |
| 2077 | |
| 2078 | CORE_ADDR |
| 2079 | skip_trampoline_code (pc, name) |
| 2080 | CORE_ADDR pc; |
| 2081 | char *name; |
| 2082 | { |
| 2083 | long orig_pc = pc; |
| 2084 | long prev_inst, curr_inst, loc; |
| 2085 | static CORE_ADDR dyncall = 0; |
| 2086 | static CORE_ADDR sr4export = 0; |
| 2087 | struct minimal_symbol *msym; |
| 2088 | struct unwind_table_entry *u; |
| 2089 | |
| 2090 | /* FIXME XXX - dyncall and sr4export must be initialized whenever we get a |
| 2091 | new exec file */ |
| 2092 | |
| 2093 | if (!dyncall) |
| 2094 | { |
| 2095 | msym = lookup_minimal_symbol ("$$dyncall", NULL, NULL); |
| 2096 | if (msym) |
| 2097 | dyncall = SYMBOL_VALUE_ADDRESS (msym); |
| 2098 | else |
| 2099 | dyncall = -1; |
| 2100 | } |
| 2101 | |
| 2102 | if (!sr4export) |
| 2103 | { |
| 2104 | msym = lookup_minimal_symbol ("_sr4export", NULL, NULL); |
| 2105 | if (msym) |
| 2106 | sr4export = SYMBOL_VALUE_ADDRESS (msym); |
| 2107 | else |
| 2108 | sr4export = -1; |
| 2109 | } |
| 2110 | |
| 2111 | /* Addresses passed to dyncall may *NOT* be the actual address |
| 2112 | of the function. So we may have to do something special. */ |
| 2113 | if (pc == dyncall) |
| 2114 | { |
| 2115 | pc = (CORE_ADDR) read_register (22); |
| 2116 | |
| 2117 | /* If bit 30 (counting from the left) is on, then pc is the address of |
| 2118 | the PLT entry for this function, not the address of the function |
| 2119 | itself. Bit 31 has meaning too, but only for MPE. */ |
| 2120 | if (pc & 0x2) |
| 2121 | pc = (CORE_ADDR) read_memory_integer (pc & ~0x3, 4); |
| 2122 | } |
| 2123 | else if (pc == sr4export) |
| 2124 | pc = (CORE_ADDR) (read_register (22)); |
| 2125 | |
| 2126 | /* Get the unwind descriptor corresponding to PC, return zero |
| 2127 | if no unwind was found. */ |
| 2128 | u = find_unwind_entry (pc); |
| 2129 | if (!u) |
| 2130 | return 0; |
| 2131 | |
| 2132 | /* If this isn't a linker stub, then return now. */ |
| 2133 | if (u->stub_type == 0) |
| 2134 | return orig_pc == pc ? 0 : pc & ~0x3; |
| 2135 | |
| 2136 | /* It's a stub. Search for a branch and figure out where it goes. |
| 2137 | Note we have to handle multi insn branch sequences like ldil;ble. |
| 2138 | Most (all?) other branches can be determined by examining the contents |
| 2139 | of certain registers and the stack. */ |
| 2140 | loc = pc; |
| 2141 | curr_inst = 0; |
| 2142 | prev_inst = 0; |
| 2143 | while (1) |
| 2144 | { |
| 2145 | /* Make sure we haven't walked outside the range of this stub. */ |
| 2146 | if (u != find_unwind_entry (loc)) |
| 2147 | { |
| 2148 | warning ("Unable to find branch in linker stub"); |
| 2149 | return orig_pc == pc ? 0 : pc & ~0x3; |
| 2150 | } |
| 2151 | |
| 2152 | prev_inst = curr_inst; |
| 2153 | curr_inst = read_memory_integer (loc, 4); |
| 2154 | |
| 2155 | /* Does it look like a branch external using %r1? Then it's the |
| 2156 | branch from the stub to the actual function. */ |
| 2157 | if ((curr_inst & 0xffe0e000) == 0xe0202000) |
| 2158 | { |
| 2159 | /* Yup. See if the previous instruction loaded |
| 2160 | a value into %r1. If so compute and return the jump address. */ |
| 2161 | if ((prev_inst & 0xffe00000) == 0x20200000) |
| 2162 | return (extract_21 (prev_inst) + extract_17 (curr_inst)) & ~0x3; |
| 2163 | else |
| 2164 | { |
| 2165 | warning ("Unable to find ldil X,%%r1 before ble Y(%%sr4,%%r1)."); |
| 2166 | return orig_pc == pc ? 0 : pc & ~0x3; |
| 2167 | } |
| 2168 | } |
| 2169 | |
| 2170 | /* Does it look like a be 0(sr0,%r21)? That's the branch from an |
| 2171 | import stub to an export stub. |
| 2172 | |
| 2173 | It is impossible to determine the target of the branch via |
| 2174 | simple examination of instructions and/or data (consider |
| 2175 | that the address in the plabel may be the address of the |
| 2176 | bind-on-reference routine in the dynamic loader). |
| 2177 | |
| 2178 | So we have try an alternative approach. |
| 2179 | |
| 2180 | Get the name of the symbol at our current location; it should |
| 2181 | be a stub symbol with the same name as the symbol in the |
| 2182 | shared library. |
| 2183 | |
| 2184 | Then lookup a minimal symbol with the same name; we should |
| 2185 | get the minimal symbol for the target routine in the shared |
| 2186 | library as those take precedence of import/export stubs. */ |
| 2187 | if (curr_inst == 0xe2a00000) |
| 2188 | { |
| 2189 | struct minimal_symbol *stubsym, *libsym; |
| 2190 | |
| 2191 | stubsym = lookup_minimal_symbol_by_pc (loc); |
| 2192 | if (stubsym == NULL) |
| 2193 | { |
| 2194 | warning ("Unable to find symbol for 0x%x", loc); |
| 2195 | return orig_pc == pc ? 0 : pc & ~0x3; |
| 2196 | } |
| 2197 | |
| 2198 | libsym = lookup_minimal_symbol (SYMBOL_NAME (stubsym), NULL, NULL); |
| 2199 | if (libsym == NULL) |
| 2200 | { |
| 2201 | warning ("Unable to find library symbol for %s\n", |
| 2202 | SYMBOL_NAME (stubsym)); |
| 2203 | return orig_pc == pc ? 0 : pc & ~0x3; |
| 2204 | } |
| 2205 | |
| 2206 | return SYMBOL_VALUE (libsym); |
| 2207 | } |
| 2208 | |
| 2209 | /* Does it look like bl X,%rp or bl X,%r0? Another way to do a |
| 2210 | branch from the stub to the actual function. */ |
| 2211 | else if ((curr_inst & 0xffe0e000) == 0xe8400000 |
| 2212 | || (curr_inst & 0xffe0e000) == 0xe8000000) |
| 2213 | return (loc + extract_17 (curr_inst) + 8) & ~0x3; |
| 2214 | |
| 2215 | /* Does it look like bv (rp)? Note this depends on the |
| 2216 | current stack pointer being the same as the stack |
| 2217 | pointer in the stub itself! This is a branch on from the |
| 2218 | stub back to the original caller. */ |
| 2219 | else if ((curr_inst & 0xffe0e000) == 0xe840c000) |
| 2220 | { |
| 2221 | /* Yup. See if the previous instruction loaded |
| 2222 | rp from sp - 8. */ |
| 2223 | if (prev_inst == 0x4bc23ff1) |
| 2224 | return (read_memory_integer |
| 2225 | (read_register (SP_REGNUM) - 8, 4)) & ~0x3; |
| 2226 | else |
| 2227 | { |
| 2228 | warning ("Unable to find restore of %%rp before bv (%%rp)."); |
| 2229 | return orig_pc == pc ? 0 : pc & ~0x3; |
| 2230 | } |
| 2231 | } |
| 2232 | |
| 2233 | /* What about be,n 0(sr0,%rp)? It's just another way we return to |
| 2234 | the original caller from the stub. Used in dynamic executables. */ |
| 2235 | else if (curr_inst == 0xe0400002) |
| 2236 | { |
| 2237 | /* The value we jump to is sitting in sp - 24. But that's |
| 2238 | loaded several instructions before the be instruction. |
| 2239 | I guess we could check for the previous instruction being |
| 2240 | mtsp %r1,%sr0 if we want to do sanity checking. */ |
| 2241 | return (read_memory_integer |
| 2242 | (read_register (SP_REGNUM) - 24, 4)) & ~0x3; |
| 2243 | } |
| 2244 | |
| 2245 | /* Haven't found the branch yet, but we're still in the stub. |
| 2246 | Keep looking. */ |
| 2247 | loc += 4; |
| 2248 | } |
| 2249 | } |
| 2250 | |
| 2251 | /* For the given instruction (INST), return any adjustment it makes |
| 2252 | to the stack pointer or zero for no adjustment. |
| 2253 | |
| 2254 | This only handles instructions commonly found in prologues. */ |
| 2255 | |
| 2256 | static int |
| 2257 | prologue_inst_adjust_sp (inst) |
| 2258 | unsigned long inst; |
| 2259 | { |
| 2260 | /* This must persist across calls. */ |
| 2261 | static int save_high21; |
| 2262 | |
| 2263 | /* The most common way to perform a stack adjustment ldo X(sp),sp */ |
| 2264 | if ((inst & 0xffffc000) == 0x37de0000) |
| 2265 | return extract_14 (inst); |
| 2266 | |
| 2267 | /* stwm X,D(sp) */ |
| 2268 | if ((inst & 0xffe00000) == 0x6fc00000) |
| 2269 | return extract_14 (inst); |
| 2270 | |
| 2271 | /* addil high21,%r1; ldo low11,(%r1),%r30) |
| 2272 | save high bits in save_high21 for later use. */ |
| 2273 | if ((inst & 0xffe00000) == 0x28200000) |
| 2274 | { |
| 2275 | save_high21 = extract_21 (inst); |
| 2276 | return 0; |
| 2277 | } |
| 2278 | |
| 2279 | if ((inst & 0xffff0000) == 0x343e0000) |
| 2280 | return save_high21 + extract_14 (inst); |
| 2281 | |
| 2282 | /* fstws as used by the HP compilers. */ |
| 2283 | if ((inst & 0xffffffe0) == 0x2fd01220) |
| 2284 | return extract_5_load (inst); |
| 2285 | |
| 2286 | /* No adjustment. */ |
| 2287 | return 0; |
| 2288 | } |
| 2289 | |
| 2290 | /* Return nonzero if INST is a branch of some kind, else return zero. */ |
| 2291 | |
| 2292 | static int |
| 2293 | is_branch (inst) |
| 2294 | unsigned long inst; |
| 2295 | { |
| 2296 | switch (inst >> 26) |
| 2297 | { |
| 2298 | case 0x20: |
| 2299 | case 0x21: |
| 2300 | case 0x22: |
| 2301 | case 0x23: |
| 2302 | case 0x28: |
| 2303 | case 0x29: |
| 2304 | case 0x2a: |
| 2305 | case 0x2b: |
| 2306 | case 0x30: |
| 2307 | case 0x31: |
| 2308 | case 0x32: |
| 2309 | case 0x33: |
| 2310 | case 0x38: |
| 2311 | case 0x39: |
| 2312 | case 0x3a: |
| 2313 | return 1; |
| 2314 | |
| 2315 | default: |
| 2316 | return 0; |
| 2317 | } |
| 2318 | } |
| 2319 | |
| 2320 | /* Return the register number for a GR which is saved by INST or |
| 2321 | zero it INST does not save a GR. */ |
| 2322 | |
| 2323 | static int |
| 2324 | inst_saves_gr (inst) |
| 2325 | unsigned long inst; |
| 2326 | { |
| 2327 | /* Does it look like a stw? */ |
| 2328 | if ((inst >> 26) == 0x1a) |
| 2329 | return extract_5R_store (inst); |
| 2330 | |
| 2331 | /* Does it look like a stwm? GCC & HPC may use this in prologues. */ |
| 2332 | if ((inst >> 26) == 0x1b) |
| 2333 | return extract_5R_store (inst); |
| 2334 | |
| 2335 | /* Does it look like sth or stb? HPC versions 9.0 and later use these |
| 2336 | too. */ |
| 2337 | if ((inst >> 26) == 0x19 || (inst >> 26) == 0x18) |
| 2338 | return extract_5R_store (inst); |
| 2339 | |
| 2340 | return 0; |
| 2341 | } |
| 2342 | |
| 2343 | /* Return the register number for a FR which is saved by INST or |
| 2344 | zero it INST does not save a FR. |
| 2345 | |
| 2346 | Note we only care about full 64bit register stores (that's the only |
| 2347 | kind of stores the prologue will use). |
| 2348 | |
| 2349 | FIXME: What about argument stores with the HP compiler in ANSI mode? */ |
| 2350 | |
| 2351 | static int |
| 2352 | inst_saves_fr (inst) |
| 2353 | unsigned long inst; |
| 2354 | { |
| 2355 | if ((inst & 0xfc00dfc0) == 0x2c001200) |
| 2356 | return extract_5r_store (inst); |
| 2357 | return 0; |
| 2358 | } |
| 2359 | |
| 2360 | /* Advance PC across any function entry prologue instructions |
| 2361 | to reach some "real" code. |
| 2362 | |
| 2363 | Use information in the unwind table to determine what exactly should |
| 2364 | be in the prologue. */ |
| 2365 | |
| 2366 | CORE_ADDR |
| 2367 | skip_prologue (pc) |
| 2368 | CORE_ADDR pc; |
| 2369 | { |
| 2370 | char buf[4]; |
| 2371 | CORE_ADDR orig_pc = pc; |
| 2372 | unsigned long inst, stack_remaining, save_gr, save_fr, save_rp, save_sp; |
| 2373 | unsigned long args_stored, status, i, restart_gr, restart_fr; |
| 2374 | struct unwind_table_entry *u; |
| 2375 | |
| 2376 | restart_gr = 0; |
| 2377 | restart_fr = 0; |
| 2378 | |
| 2379 | restart: |
| 2380 | u = find_unwind_entry (pc); |
| 2381 | if (!u) |
| 2382 | return pc; |
| 2383 | |
| 2384 | /* If we are not at the beginning of a function, then return now. */ |
| 2385 | if ((pc & ~0x3) != u->region_start) |
| 2386 | return pc; |
| 2387 | |
| 2388 | /* This is how much of a frame adjustment we need to account for. */ |
| 2389 | stack_remaining = u->Total_frame_size << 3; |
| 2390 | |
| 2391 | /* Magic register saves we want to know about. */ |
| 2392 | save_rp = u->Save_RP; |
| 2393 | save_sp = u->Save_SP; |
| 2394 | |
| 2395 | /* An indication that args may be stored into the stack. Unfortunately |
| 2396 | the HPUX compilers tend to set this in cases where no args were |
| 2397 | stored too!. */ |
| 2398 | args_stored = 1; |
| 2399 | |
| 2400 | /* Turn the Entry_GR field into a bitmask. */ |
| 2401 | save_gr = 0; |
| 2402 | for (i = 3; i < u->Entry_GR + 3; i++) |
| 2403 | { |
| 2404 | /* Frame pointer gets saved into a special location. */ |
| 2405 | if (u->Save_SP && i == FP_REGNUM) |
| 2406 | continue; |
| 2407 | |
| 2408 | save_gr |= (1 << i); |
| 2409 | } |
| 2410 | save_gr &= ~restart_gr; |
| 2411 | |
| 2412 | /* Turn the Entry_FR field into a bitmask too. */ |
| 2413 | save_fr = 0; |
| 2414 | for (i = 12; i < u->Entry_FR + 12; i++) |
| 2415 | save_fr |= (1 << i); |
| 2416 | save_fr &= ~restart_fr; |
| 2417 | |
| 2418 | /* Loop until we find everything of interest or hit a branch. |
| 2419 | |
| 2420 | For unoptimized GCC code and for any HP CC code this will never ever |
| 2421 | examine any user instructions. |
| 2422 | |
| 2423 | For optimzied GCC code we're faced with problems. GCC will schedule |
| 2424 | its prologue and make prologue instructions available for delay slot |
| 2425 | filling. The end result is user code gets mixed in with the prologue |
| 2426 | and a prologue instruction may be in the delay slot of the first branch |
| 2427 | or call. |
| 2428 | |
| 2429 | Some unexpected things are expected with debugging optimized code, so |
| 2430 | we allow this routine to walk past user instructions in optimized |
| 2431 | GCC code. */ |
| 2432 | while (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0 |
| 2433 | || args_stored) |
| 2434 | { |
| 2435 | unsigned int reg_num; |
| 2436 | unsigned long old_stack_remaining, old_save_gr, old_save_fr; |
| 2437 | unsigned long old_save_rp, old_save_sp, next_inst; |
| 2438 | |
| 2439 | /* Save copies of all the triggers so we can compare them later |
| 2440 | (only for HPC). */ |
| 2441 | old_save_gr = save_gr; |
| 2442 | old_save_fr = save_fr; |
| 2443 | old_save_rp = save_rp; |
| 2444 | old_save_sp = save_sp; |
| 2445 | old_stack_remaining = stack_remaining; |
| 2446 | |
| 2447 | status = target_read_memory (pc, buf, 4); |
| 2448 | inst = extract_unsigned_integer (buf, 4); |
| 2449 | |
| 2450 | /* Yow! */ |
| 2451 | if (status != 0) |
| 2452 | return pc; |
| 2453 | |
| 2454 | /* Note the interesting effects of this instruction. */ |
| 2455 | stack_remaining -= prologue_inst_adjust_sp (inst); |
| 2456 | |
| 2457 | /* There is only one instruction used for saving RP into the stack. */ |
| 2458 | if (inst == 0x6bc23fd9) |
| 2459 | save_rp = 0; |
| 2460 | |
| 2461 | /* This is the only way we save SP into the stack. At this time |
| 2462 | the HP compilers never bother to save SP into the stack. */ |
| 2463 | if ((inst & 0xffffc000) == 0x6fc10000) |
| 2464 | save_sp = 0; |
| 2465 | |
| 2466 | /* Account for general and floating-point register saves. */ |
| 2467 | reg_num = inst_saves_gr (inst); |
| 2468 | save_gr &= ~(1 << reg_num); |
| 2469 | |
| 2470 | /* Ugh. Also account for argument stores into the stack. |
| 2471 | Unfortunately args_stored only tells us that some arguments |
| 2472 | where stored into the stack. Not how many or what kind! |
| 2473 | |
| 2474 | This is a kludge as on the HP compiler sets this bit and it |
| 2475 | never does prologue scheduling. So once we see one, skip past |
| 2476 | all of them. We have similar code for the fp arg stores below. |
| 2477 | |
| 2478 | FIXME. Can still die if we have a mix of GR and FR argument |
| 2479 | stores! */ |
| 2480 | if (reg_num >= 23 && reg_num <= 26) |
| 2481 | { |
| 2482 | while (reg_num >= 23 && reg_num <= 26) |
| 2483 | { |
| 2484 | pc += 4; |
| 2485 | status = target_read_memory (pc, buf, 4); |
| 2486 | inst = extract_unsigned_integer (buf, 4); |
| 2487 | if (status != 0) |
| 2488 | return pc; |
| 2489 | reg_num = inst_saves_gr (inst); |
| 2490 | } |
| 2491 | args_stored = 0; |
| 2492 | continue; |
| 2493 | } |
| 2494 | |
| 2495 | reg_num = inst_saves_fr (inst); |
| 2496 | save_fr &= ~(1 << reg_num); |
| 2497 | |
| 2498 | status = target_read_memory (pc + 4, buf, 4); |
| 2499 | next_inst = extract_unsigned_integer (buf, 4); |
| 2500 | |
| 2501 | /* Yow! */ |
| 2502 | if (status != 0) |
| 2503 | return pc; |
| 2504 | |
| 2505 | /* We've got to be read to handle the ldo before the fp register |
| 2506 | save. */ |
| 2507 | if ((inst & 0xfc000000) == 0x34000000 |
| 2508 | && inst_saves_fr (next_inst) >= 4 |
| 2509 | && inst_saves_fr (next_inst) <= 7) |
| 2510 | { |
| 2511 | /* So we drop into the code below in a reasonable state. */ |
| 2512 | reg_num = inst_saves_fr (next_inst); |
| 2513 | pc -= 4; |
| 2514 | } |
| 2515 | |
| 2516 | /* Ugh. Also account for argument stores into the stack. |
| 2517 | This is a kludge as on the HP compiler sets this bit and it |
| 2518 | never does prologue scheduling. So once we see one, skip past |
| 2519 | all of them. */ |
| 2520 | if (reg_num >= 4 && reg_num <= 7) |
| 2521 | { |
| 2522 | while (reg_num >= 4 && reg_num <= 7) |
| 2523 | { |
| 2524 | pc += 8; |
| 2525 | status = target_read_memory (pc, buf, 4); |
| 2526 | inst = extract_unsigned_integer (buf, 4); |
| 2527 | if (status != 0) |
| 2528 | return pc; |
| 2529 | if ((inst & 0xfc000000) != 0x34000000) |
| 2530 | break; |
| 2531 | status = target_read_memory (pc + 4, buf, 4); |
| 2532 | next_inst = extract_unsigned_integer (buf, 4); |
| 2533 | if (status != 0) |
| 2534 | return pc; |
| 2535 | reg_num = inst_saves_fr (next_inst); |
| 2536 | } |
| 2537 | args_stored = 0; |
| 2538 | continue; |
| 2539 | } |
| 2540 | |
| 2541 | /* Quit if we hit any kind of branch. This can happen if a prologue |
| 2542 | instruction is in the delay slot of the first call/branch. */ |
| 2543 | if (is_branch (inst)) |
| 2544 | break; |
| 2545 | |
| 2546 | /* What a crock. The HP compilers set args_stored even if no |
| 2547 | arguments were stored into the stack (boo hiss). This could |
| 2548 | cause this code to then skip a bunch of user insns (up to the |
| 2549 | first branch). |
| 2550 | |
| 2551 | To combat this we try to identify when args_stored was bogusly |
| 2552 | set and clear it. We only do this when args_stored is nonzero, |
| 2553 | all other resources are accounted for, and nothing changed on |
| 2554 | this pass. */ |
| 2555 | if (args_stored |
| 2556 | && ! (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0) |
| 2557 | && old_save_gr == save_gr && old_save_fr == save_fr |
| 2558 | && old_save_rp == save_rp && old_save_sp == save_sp |
| 2559 | && old_stack_remaining == stack_remaining) |
| 2560 | break; |
| 2561 | |
| 2562 | /* Bump the PC. */ |
| 2563 | pc += 4; |
| 2564 | } |
| 2565 | |
| 2566 | /* We've got a tenative location for the end of the prologue. However |
| 2567 | because of limitations in the unwind descriptor mechanism we may |
| 2568 | have went too far into user code looking for the save of a register |
| 2569 | that does not exist. So, if there registers we expected to be saved |
| 2570 | but never were, mask them out and restart. |
| 2571 | |
| 2572 | This should only happen in optimized code, and should be very rare. */ |
| 2573 | if (save_gr || (save_fr && ! (restart_fr || restart_gr))) |
| 2574 | { |
| 2575 | pc = orig_pc; |
| 2576 | restart_gr = save_gr; |
| 2577 | restart_fr = save_fr; |
| 2578 | goto restart; |
| 2579 | } |
| 2580 | |
| 2581 | return pc; |
| 2582 | } |
| 2583 | |
| 2584 | /* Put here the code to store, into a struct frame_saved_regs, |
| 2585 | the addresses of the saved registers of frame described by FRAME_INFO. |
| 2586 | This includes special registers such as pc and fp saved in special |
| 2587 | ways in the stack frame. sp is even more special: |
| 2588 | the address we return for it IS the sp for the next frame. */ |
| 2589 | |
| 2590 | void |
| 2591 | hppa_frame_find_saved_regs (frame_info, frame_saved_regs) |
| 2592 | struct frame_info *frame_info; |
| 2593 | struct frame_saved_regs *frame_saved_regs; |
| 2594 | { |
| 2595 | CORE_ADDR pc; |
| 2596 | struct unwind_table_entry *u; |
| 2597 | unsigned long inst, stack_remaining, save_gr, save_fr, save_rp, save_sp; |
| 2598 | int status, i, reg; |
| 2599 | char buf[4]; |
| 2600 | int fp_loc = -1; |
| 2601 | |
| 2602 | /* Zero out everything. */ |
| 2603 | memset (frame_saved_regs, '\0', sizeof (struct frame_saved_regs)); |
| 2604 | |
| 2605 | /* Call dummy frames always look the same, so there's no need to |
| 2606 | examine the dummy code to determine locations of saved registers; |
| 2607 | instead, let find_dummy_frame_regs fill in the correct offsets |
| 2608 | for the saved registers. */ |
| 2609 | if ((frame_info->pc >= frame_info->frame |
| 2610 | && frame_info->pc <= (frame_info->frame + CALL_DUMMY_LENGTH |
| 2611 | + 32 * 4 + (NUM_REGS - FP0_REGNUM) * 8 |
| 2612 | + 6 * 4))) |
| 2613 | find_dummy_frame_regs (frame_info, frame_saved_regs); |
| 2614 | |
| 2615 | /* Interrupt handlers are special too. They lay out the register |
| 2616 | state in the exact same order as the register numbers in GDB. */ |
| 2617 | if (pc_in_interrupt_handler (frame_info->pc)) |
| 2618 | { |
| 2619 | for (i = 0; i < NUM_REGS; i++) |
| 2620 | { |
| 2621 | /* SP is a little special. */ |
| 2622 | if (i == SP_REGNUM) |
| 2623 | frame_saved_regs->regs[SP_REGNUM] |
| 2624 | = read_memory_integer (frame_info->frame + SP_REGNUM * 4, 4); |
| 2625 | else |
| 2626 | frame_saved_regs->regs[i] = frame_info->frame + i * 4; |
| 2627 | } |
| 2628 | return; |
| 2629 | } |
| 2630 | |
| 2631 | #ifdef FRAME_FIND_SAVED_REGS_IN_SIGTRAMP |
| 2632 | /* Handle signal handler callers. */ |
| 2633 | if (frame_info->signal_handler_caller) |
| 2634 | { |
| 2635 | FRAME_FIND_SAVED_REGS_IN_SIGTRAMP (frame_info, frame_saved_regs); |
| 2636 | return; |
| 2637 | } |
| 2638 | #endif |
| 2639 | |
| 2640 | /* Get the starting address of the function referred to by the PC |
| 2641 | saved in frame. */ |
| 2642 | pc = get_pc_function_start (frame_info->pc); |
| 2643 | |
| 2644 | /* Yow! */ |
| 2645 | u = find_unwind_entry (pc); |
| 2646 | if (!u) |
| 2647 | return; |
| 2648 | |
| 2649 | /* This is how much of a frame adjustment we need to account for. */ |
| 2650 | stack_remaining = u->Total_frame_size << 3; |
| 2651 | |
| 2652 | /* Magic register saves we want to know about. */ |
| 2653 | save_rp = u->Save_RP; |
| 2654 | save_sp = u->Save_SP; |
| 2655 | |
| 2656 | /* Turn the Entry_GR field into a bitmask. */ |
| 2657 | save_gr = 0; |
| 2658 | for (i = 3; i < u->Entry_GR + 3; i++) |
| 2659 | { |
| 2660 | /* Frame pointer gets saved into a special location. */ |
| 2661 | if (u->Save_SP && i == FP_REGNUM) |
| 2662 | continue; |
| 2663 | |
| 2664 | save_gr |= (1 << i); |
| 2665 | } |
| 2666 | |
| 2667 | /* Turn the Entry_FR field into a bitmask too. */ |
| 2668 | save_fr = 0; |
| 2669 | for (i = 12; i < u->Entry_FR + 12; i++) |
| 2670 | save_fr |= (1 << i); |
| 2671 | |
| 2672 | /* The frame always represents the value of %sp at entry to the |
| 2673 | current function (and is thus equivalent to the "saved" stack |
| 2674 | pointer. */ |
| 2675 | frame_saved_regs->regs[SP_REGNUM] = frame_info->frame; |
| 2676 | |
| 2677 | /* Loop until we find everything of interest or hit a branch. |
| 2678 | |
| 2679 | For unoptimized GCC code and for any HP CC code this will never ever |
| 2680 | examine any user instructions. |
| 2681 | |
| 2682 | For optimzied GCC code we're faced with problems. GCC will schedule |
| 2683 | its prologue and make prologue instructions available for delay slot |
| 2684 | filling. The end result is user code gets mixed in with the prologue |
| 2685 | and a prologue instruction may be in the delay slot of the first branch |
| 2686 | or call. |
| 2687 | |
| 2688 | Some unexpected things are expected with debugging optimized code, so |
| 2689 | we allow this routine to walk past user instructions in optimized |
| 2690 | GCC code. */ |
| 2691 | while (save_gr || save_fr || save_rp || save_sp || stack_remaining > 0) |
| 2692 | { |
| 2693 | status = target_read_memory (pc, buf, 4); |
| 2694 | inst = extract_unsigned_integer (buf, 4); |
| 2695 | |
| 2696 | /* Yow! */ |
| 2697 | if (status != 0) |
| 2698 | return; |
| 2699 | |
| 2700 | /* Note the interesting effects of this instruction. */ |
| 2701 | stack_remaining -= prologue_inst_adjust_sp (inst); |
| 2702 | |
| 2703 | /* There is only one instruction used for saving RP into the stack. */ |
| 2704 | if (inst == 0x6bc23fd9) |
| 2705 | { |
| 2706 | save_rp = 0; |
| 2707 | frame_saved_regs->regs[RP_REGNUM] = frame_info->frame - 20; |
| 2708 | } |
| 2709 | |
| 2710 | /* Just note that we found the save of SP into the stack. The |
| 2711 | value for frame_saved_regs was computed above. */ |
| 2712 | if ((inst & 0xffffc000) == 0x6fc10000) |
| 2713 | save_sp = 0; |
| 2714 | |
| 2715 | /* Account for general and floating-point register saves. */ |
| 2716 | reg = inst_saves_gr (inst); |
| 2717 | if (reg >= 3 && reg <= 18 |
| 2718 | && (!u->Save_SP || reg != FP_REGNUM)) |
| 2719 | { |
| 2720 | save_gr &= ~(1 << reg); |
| 2721 | |
| 2722 | /* stwm with a positive displacement is a *post modify*. */ |
| 2723 | if ((inst >> 26) == 0x1b |
| 2724 | && extract_14 (inst) >= 0) |
| 2725 | frame_saved_regs->regs[reg] = frame_info->frame; |
| 2726 | else |
| 2727 | { |
| 2728 | /* Handle code with and without frame pointers. */ |
| 2729 | if (u->Save_SP) |
| 2730 | frame_saved_regs->regs[reg] |
| 2731 | = frame_info->frame + extract_14 (inst); |
| 2732 | else |
| 2733 | frame_saved_regs->regs[reg] |
| 2734 | = frame_info->frame + (u->Total_frame_size << 3) |
| 2735 | + extract_14 (inst); |
| 2736 | } |
| 2737 | } |
| 2738 | |
| 2739 | |
| 2740 | /* GCC handles callee saved FP regs a little differently. |
| 2741 | |
| 2742 | It emits an instruction to put the value of the start of |
| 2743 | the FP store area into %r1. It then uses fstds,ma with |
| 2744 | a basereg of %r1 for the stores. |
| 2745 | |
| 2746 | HP CC emits them at the current stack pointer modifying |
| 2747 | the stack pointer as it stores each register. */ |
| 2748 | |
| 2749 | /* ldo X(%r3),%r1 or ldo X(%r30),%r1. */ |
| 2750 | if ((inst & 0xffffc000) == 0x34610000 |
| 2751 | || (inst & 0xffffc000) == 0x37c10000) |
| 2752 | fp_loc = extract_14 (inst); |
| 2753 | |
| 2754 | reg = inst_saves_fr (inst); |
| 2755 | if (reg >= 12 && reg <= 21) |
| 2756 | { |
| 2757 | /* Note +4 braindamage below is necessary because the FP status |
| 2758 | registers are internally 8 registers rather than the expected |
| 2759 | 4 registers. */ |
| 2760 | save_fr &= ~(1 << reg); |
| 2761 | if (fp_loc == -1) |
| 2762 | { |
| 2763 | /* 1st HP CC FP register store. After this instruction |
| 2764 | we've set enough state that the GCC and HPCC code are |
| 2765 | both handled in the same manner. */ |
| 2766 | frame_saved_regs->regs[reg + FP4_REGNUM + 4] = frame_info->frame; |
| 2767 | fp_loc = 8; |
| 2768 | } |
| 2769 | else |
| 2770 | { |
| 2771 | frame_saved_regs->regs[reg + FP0_REGNUM + 4] |
| 2772 | = frame_info->frame + fp_loc; |
| 2773 | fp_loc += 8; |
| 2774 | } |
| 2775 | } |
| 2776 | |
| 2777 | /* Quit if we hit any kind of branch. This can happen if a prologue |
| 2778 | instruction is in the delay slot of the first call/branch. */ |
| 2779 | if (is_branch (inst)) |
| 2780 | break; |
| 2781 | |
| 2782 | /* Bump the PC. */ |
| 2783 | pc += 4; |
| 2784 | } |
| 2785 | } |
| 2786 | |
| 2787 | #ifdef MAINTENANCE_CMDS |
| 2788 | |
| 2789 | static void |
| 2790 | unwind_command (exp, from_tty) |
| 2791 | char *exp; |
| 2792 | int from_tty; |
| 2793 | { |
| 2794 | CORE_ADDR address; |
| 2795 | struct unwind_table_entry *u; |
| 2796 | |
| 2797 | /* If we have an expression, evaluate it and use it as the address. */ |
| 2798 | |
| 2799 | if (exp != 0 && *exp != 0) |
| 2800 | address = parse_and_eval_address (exp); |
| 2801 | else |
| 2802 | return; |
| 2803 | |
| 2804 | u = find_unwind_entry (address); |
| 2805 | |
| 2806 | if (!u) |
| 2807 | { |
| 2808 | printf_unfiltered ("Can't find unwind table entry for %s\n", exp); |
| 2809 | return; |
| 2810 | } |
| 2811 | |
| 2812 | printf_unfiltered ("unwind_table_entry (0x%x):\n", u); |
| 2813 | |
| 2814 | printf_unfiltered ("\tregion_start = "); |
| 2815 | print_address (u->region_start, gdb_stdout); |
| 2816 | |
| 2817 | printf_unfiltered ("\n\tregion_end = "); |
| 2818 | print_address (u->region_end, gdb_stdout); |
| 2819 | |
| 2820 | #ifdef __STDC__ |
| 2821 | #define pif(FLD) if (u->FLD) printf_unfiltered (" "#FLD); |
| 2822 | #else |
| 2823 | #define pif(FLD) if (u->FLD) printf_unfiltered (" FLD"); |
| 2824 | #endif |
| 2825 | |
| 2826 | printf_unfiltered ("\n\tflags ="); |
| 2827 | pif (Cannot_unwind); |
| 2828 | pif (Millicode); |
| 2829 | pif (Millicode_save_sr0); |
| 2830 | pif (Entry_SR); |
| 2831 | pif (Args_stored); |
| 2832 | pif (Variable_Frame); |
| 2833 | pif (Separate_Package_Body); |
| 2834 | pif (Frame_Extension_Millicode); |
| 2835 | pif (Stack_Overflow_Check); |
| 2836 | pif (Two_Instruction_SP_Increment); |
| 2837 | pif (Ada_Region); |
| 2838 | pif (Save_SP); |
| 2839 | pif (Save_RP); |
| 2840 | pif (Save_MRP_in_frame); |
| 2841 | pif (extn_ptr_defined); |
| 2842 | pif (Cleanup_defined); |
| 2843 | pif (MPE_XL_interrupt_marker); |
| 2844 | pif (HP_UX_interrupt_marker); |
| 2845 | pif (Large_frame); |
| 2846 | |
| 2847 | putchar_unfiltered ('\n'); |
| 2848 | |
| 2849 | #ifdef __STDC__ |
| 2850 | #define pin(FLD) printf_unfiltered ("\t"#FLD" = 0x%x\n", u->FLD); |
| 2851 | #else |
| 2852 | #define pin(FLD) printf_unfiltered ("\tFLD = 0x%x\n", u->FLD); |
| 2853 | #endif |
| 2854 | |
| 2855 | pin (Region_description); |
| 2856 | pin (Entry_FR); |
| 2857 | pin (Entry_GR); |
| 2858 | pin (Total_frame_size); |
| 2859 | } |
| 2860 | #endif /* MAINTENANCE_CMDS */ |
| 2861 | |
| 2862 | void |
| 2863 | _initialize_hppa_tdep () |
| 2864 | { |
| 2865 | tm_print_insn = print_insn_hppa; |
| 2866 | |
| 2867 | #ifdef MAINTENANCE_CMDS |
| 2868 | add_cmd ("unwind", class_maintenance, unwind_command, |
| 2869 | "Print unwind table entry at given address.", |
| 2870 | &maintenanceprintlist); |
| 2871 | #endif /* MAINTENANCE_CMDS */ |
| 2872 | } |