| 1 | /* Find a variable's value in memory, for GDB, the GNU debugger. |
| 2 | Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "symtab.h" |
| 22 | #include "gdbtypes.h" |
| 23 | #include "frame.h" |
| 24 | #include "value.h" |
| 25 | #include "gdbcore.h" |
| 26 | #include "inferior.h" |
| 27 | #include "target.h" |
| 28 | #include "gdb_string.h" |
| 29 | #include "floatformat.h" |
| 30 | |
| 31 | /* This is used to indicate that we don't know the format of the floating point |
| 32 | number. Typically, this is useful for native ports, where the actual format |
| 33 | is irrelevant, since no conversions will be taking place. */ |
| 34 | |
| 35 | const struct floatformat floatformat_unknown; |
| 36 | |
| 37 | /* Registers we shouldn't try to store. */ |
| 38 | #if !defined (CANNOT_STORE_REGISTER) |
| 39 | #define CANNOT_STORE_REGISTER(regno) 0 |
| 40 | #endif |
| 41 | |
| 42 | static void write_register_pid PARAMS ((int regno, LONGEST val, int pid)); |
| 43 | |
| 44 | /* Basic byte-swapping routines. GDB has needed these for a long time... |
| 45 | All extract a target-format integer at ADDR which is LEN bytes long. */ |
| 46 | |
| 47 | #if TARGET_CHAR_BIT != 8 || HOST_CHAR_BIT != 8 |
| 48 | /* 8 bit characters are a pretty safe assumption these days, so we |
| 49 | assume it throughout all these swapping routines. If we had to deal with |
| 50 | 9 bit characters, we would need to make len be in bits and would have |
| 51 | to re-write these routines... */ |
| 52 | you lose |
| 53 | #endif |
| 54 | |
| 55 | LONGEST |
| 56 | extract_signed_integer (addr, len) |
| 57 | PTR addr; |
| 58 | int len; |
| 59 | { |
| 60 | LONGEST retval; |
| 61 | unsigned char *p; |
| 62 | unsigned char *startaddr = (unsigned char *)addr; |
| 63 | unsigned char *endaddr = startaddr + len; |
| 64 | |
| 65 | if (len > (int) sizeof (LONGEST)) |
| 66 | error ("\ |
| 67 | That operation is not available on integers of more than %d bytes.", |
| 68 | sizeof (LONGEST)); |
| 69 | |
| 70 | /* Start at the most significant end of the integer, and work towards |
| 71 | the least significant. */ |
| 72 | if (TARGET_BYTE_ORDER == BIG_ENDIAN) |
| 73 | { |
| 74 | p = startaddr; |
| 75 | /* Do the sign extension once at the start. */ |
| 76 | retval = ((LONGEST)*p ^ 0x80) - 0x80; |
| 77 | for (++p; p < endaddr; ++p) |
| 78 | retval = (retval << 8) | *p; |
| 79 | } |
| 80 | else |
| 81 | { |
| 82 | p = endaddr - 1; |
| 83 | /* Do the sign extension once at the start. */ |
| 84 | retval = ((LONGEST)*p ^ 0x80) - 0x80; |
| 85 | for (--p; p >= startaddr; --p) |
| 86 | retval = (retval << 8) | *p; |
| 87 | } |
| 88 | return retval; |
| 89 | } |
| 90 | |
| 91 | unsigned LONGEST |
| 92 | extract_unsigned_integer (addr, len) |
| 93 | PTR addr; |
| 94 | int len; |
| 95 | { |
| 96 | unsigned LONGEST retval; |
| 97 | unsigned char *p; |
| 98 | unsigned char *startaddr = (unsigned char *)addr; |
| 99 | unsigned char *endaddr = startaddr + len; |
| 100 | |
| 101 | if (len > (int) sizeof (unsigned LONGEST)) |
| 102 | error ("\ |
| 103 | That operation is not available on integers of more than %d bytes.", |
| 104 | sizeof (unsigned LONGEST)); |
| 105 | |
| 106 | /* Start at the most significant end of the integer, and work towards |
| 107 | the least significant. */ |
| 108 | retval = 0; |
| 109 | if (TARGET_BYTE_ORDER == BIG_ENDIAN) |
| 110 | { |
| 111 | for (p = startaddr; p < endaddr; ++p) |
| 112 | retval = (retval << 8) | *p; |
| 113 | } |
| 114 | else |
| 115 | { |
| 116 | for (p = endaddr - 1; p >= startaddr; --p) |
| 117 | retval = (retval << 8) | *p; |
| 118 | } |
| 119 | return retval; |
| 120 | } |
| 121 | |
| 122 | /* Sometimes a long long unsigned integer can be extracted as a |
| 123 | LONGEST value. This is done so that we can print these values |
| 124 | better. If this integer can be converted to a LONGEST, this |
| 125 | function returns 1 and sets *PVAL. Otherwise it returns 0. */ |
| 126 | |
| 127 | int |
| 128 | extract_long_unsigned_integer (addr, orig_len, pval) |
| 129 | PTR addr; |
| 130 | int orig_len; |
| 131 | LONGEST *pval; |
| 132 | { |
| 133 | char *p, *first_addr; |
| 134 | int len; |
| 135 | |
| 136 | len = orig_len; |
| 137 | if (TARGET_BYTE_ORDER == BIG_ENDIAN) |
| 138 | { |
| 139 | for (p = (char *) addr; |
| 140 | len > (int) sizeof (LONGEST) && p < (char *) addr + orig_len; |
| 141 | p++) |
| 142 | { |
| 143 | if (*p == 0) |
| 144 | len--; |
| 145 | else |
| 146 | break; |
| 147 | } |
| 148 | first_addr = p; |
| 149 | } |
| 150 | else |
| 151 | { |
| 152 | first_addr = (char *) addr; |
| 153 | for (p = (char *) addr + orig_len - 1; |
| 154 | len > (int) sizeof (LONGEST) && p >= (char *) addr; |
| 155 | p--) |
| 156 | { |
| 157 | if (*p == 0) |
| 158 | len--; |
| 159 | else |
| 160 | break; |
| 161 | } |
| 162 | } |
| 163 | |
| 164 | if (len <= (int) sizeof (LONGEST)) |
| 165 | { |
| 166 | *pval = (LONGEST) extract_unsigned_integer (first_addr, |
| 167 | sizeof (LONGEST)); |
| 168 | return 1; |
| 169 | } |
| 170 | |
| 171 | return 0; |
| 172 | } |
| 173 | |
| 174 | CORE_ADDR |
| 175 | extract_address (addr, len) |
| 176 | PTR addr; |
| 177 | int len; |
| 178 | { |
| 179 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
| 180 | whether we want this to be true eventually. */ |
| 181 | return extract_unsigned_integer (addr, len); |
| 182 | } |
| 183 | |
| 184 | void |
| 185 | store_signed_integer (addr, len, val) |
| 186 | PTR addr; |
| 187 | int len; |
| 188 | LONGEST val; |
| 189 | { |
| 190 | unsigned char *p; |
| 191 | unsigned char *startaddr = (unsigned char *)addr; |
| 192 | unsigned char *endaddr = startaddr + len; |
| 193 | |
| 194 | /* Start at the least significant end of the integer, and work towards |
| 195 | the most significant. */ |
| 196 | if (TARGET_BYTE_ORDER == BIG_ENDIAN) |
| 197 | { |
| 198 | for (p = endaddr - 1; p >= startaddr; --p) |
| 199 | { |
| 200 | *p = val & 0xff; |
| 201 | val >>= 8; |
| 202 | } |
| 203 | } |
| 204 | else |
| 205 | { |
| 206 | for (p = startaddr; p < endaddr; ++p) |
| 207 | { |
| 208 | *p = val & 0xff; |
| 209 | val >>= 8; |
| 210 | } |
| 211 | } |
| 212 | } |
| 213 | |
| 214 | void |
| 215 | store_unsigned_integer (addr, len, val) |
| 216 | PTR addr; |
| 217 | int len; |
| 218 | unsigned LONGEST val; |
| 219 | { |
| 220 | unsigned char *p; |
| 221 | unsigned char *startaddr = (unsigned char *)addr; |
| 222 | unsigned char *endaddr = startaddr + len; |
| 223 | |
| 224 | /* Start at the least significant end of the integer, and work towards |
| 225 | the most significant. */ |
| 226 | if (TARGET_BYTE_ORDER == BIG_ENDIAN) |
| 227 | { |
| 228 | for (p = endaddr - 1; p >= startaddr; --p) |
| 229 | { |
| 230 | *p = val & 0xff; |
| 231 | val >>= 8; |
| 232 | } |
| 233 | } |
| 234 | else |
| 235 | { |
| 236 | for (p = startaddr; p < endaddr; ++p) |
| 237 | { |
| 238 | *p = val & 0xff; |
| 239 | val >>= 8; |
| 240 | } |
| 241 | } |
| 242 | } |
| 243 | |
| 244 | void |
| 245 | store_address (addr, len, val) |
| 246 | PTR addr; |
| 247 | int len; |
| 248 | CORE_ADDR val; |
| 249 | { |
| 250 | /* Assume a CORE_ADDR can fit in a LONGEST (for now). Not sure |
| 251 | whether we want this to be true eventually. */ |
| 252 | store_unsigned_integer (addr, len, (LONGEST)val); |
| 253 | } |
| 254 | \f |
| 255 | /* Swap LEN bytes at BUFFER between target and host byte-order. */ |
| 256 | #define SWAP_FLOATING(buffer,len) \ |
| 257 | do \ |
| 258 | { \ |
| 259 | if (TARGET_BYTE_ORDER != HOST_BYTE_ORDER) \ |
| 260 | { \ |
| 261 | char tmp; \ |
| 262 | char *p = (char *)(buffer); \ |
| 263 | char *q = ((char *)(buffer)) + len - 1; \ |
| 264 | for (; p < q; p++, q--) \ |
| 265 | { \ |
| 266 | tmp = *q; \ |
| 267 | *q = *p; \ |
| 268 | *p = tmp; \ |
| 269 | } \ |
| 270 | } \ |
| 271 | } \ |
| 272 | while (0) |
| 273 | |
| 274 | /* There are various problems with the extract_floating and store_floating |
| 275 | routines. |
| 276 | |
| 277 | 1. These routines only handle byte-swapping, not conversion of |
| 278 | formats. So if host is IEEE floating and target is VAX floating, |
| 279 | or vice-versa, it loses. This means that we can't (yet) use these |
| 280 | routines for extendeds. Extendeds are handled by |
| 281 | REGISTER_CONVERTIBLE. What we want is to use floatformat.h, but that |
| 282 | doesn't yet handle VAX floating at all. |
| 283 | |
| 284 | 2. We can't deal with it if there is more than one floating point |
| 285 | format in use. This has to be fixed at the unpack_double level. |
| 286 | |
| 287 | 3. We probably should have a LONGEST_DOUBLE or DOUBLEST or whatever |
| 288 | we want to call it which is long double where available. */ |
| 289 | |
| 290 | DOUBLEST |
| 291 | extract_floating (addr, len) |
| 292 | PTR addr; |
| 293 | int len; |
| 294 | { |
| 295 | DOUBLEST dretval; |
| 296 | |
| 297 | if (len == sizeof (float)) |
| 298 | { |
| 299 | if (HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT) |
| 300 | { |
| 301 | float retval; |
| 302 | |
| 303 | memcpy (&retval, addr, sizeof (retval)); |
| 304 | return retval; |
| 305 | } |
| 306 | else |
| 307 | FLOATFORMAT_TO_DOUBLEST (TARGET_FLOAT_FORMAT, addr, &dretval); |
| 308 | } |
| 309 | else if (len == sizeof (double)) |
| 310 | { |
| 311 | if (HOST_DOUBLE_FORMAT == TARGET_DOUBLE_FORMAT) |
| 312 | { |
| 313 | double retval; |
| 314 | |
| 315 | memcpy (&retval, addr, sizeof (retval)); |
| 316 | return retval; |
| 317 | } |
| 318 | else |
| 319 | FLOATFORMAT_TO_DOUBLEST (TARGET_DOUBLE_FORMAT, addr, &dretval); |
| 320 | } |
| 321 | else if (len == sizeof (DOUBLEST)) |
| 322 | { |
| 323 | if (HOST_LONG_DOUBLE_FORMAT == TARGET_LONG_DOUBLE_FORMAT) |
| 324 | { |
| 325 | DOUBLEST retval; |
| 326 | |
| 327 | memcpy (&retval, addr, sizeof (retval)); |
| 328 | return retval; |
| 329 | } |
| 330 | else |
| 331 | FLOATFORMAT_TO_DOUBLEST (TARGET_LONG_DOUBLE_FORMAT, addr, &dretval); |
| 332 | } |
| 333 | else |
| 334 | { |
| 335 | error ("Can't deal with a floating point number of %d bytes.", len); |
| 336 | } |
| 337 | |
| 338 | return dretval; |
| 339 | } |
| 340 | |
| 341 | void |
| 342 | store_floating (addr, len, val) |
| 343 | PTR addr; |
| 344 | int len; |
| 345 | DOUBLEST val; |
| 346 | { |
| 347 | if (len == sizeof (float)) |
| 348 | { |
| 349 | if (HOST_FLOAT_FORMAT == TARGET_FLOAT_FORMAT) |
| 350 | { |
| 351 | float floatval = val; |
| 352 | |
| 353 | memcpy (addr, &floatval, sizeof (floatval)); |
| 354 | } |
| 355 | else |
| 356 | FLOATFORMAT_FROM_DOUBLEST (TARGET_FLOAT_FORMAT, &val, addr); |
| 357 | } |
| 358 | else if (len == sizeof (double)) |
| 359 | { |
| 360 | if (HOST_DOUBLE_FORMAT == TARGET_DOUBLE_FORMAT) |
| 361 | { |
| 362 | double doubleval = val; |
| 363 | |
| 364 | memcpy (addr, &doubleval, sizeof (doubleval)); |
| 365 | } |
| 366 | else |
| 367 | FLOATFORMAT_FROM_DOUBLEST (TARGET_DOUBLE_FORMAT, &val, addr); |
| 368 | } |
| 369 | else if (len == sizeof (DOUBLEST)) |
| 370 | { |
| 371 | if (HOST_LONG_DOUBLE_FORMAT == TARGET_LONG_DOUBLE_FORMAT) |
| 372 | memcpy (addr, &val, sizeof (val)); |
| 373 | else |
| 374 | FLOATFORMAT_FROM_DOUBLEST (TARGET_LONG_DOUBLE_FORMAT, &val, addr); |
| 375 | } |
| 376 | else |
| 377 | { |
| 378 | error ("Can't deal with a floating point number of %d bytes.", len); |
| 379 | } |
| 380 | } |
| 381 | \f |
| 382 | #if !defined (GET_SAVED_REGISTER) |
| 383 | |
| 384 | /* Return the address in which frame FRAME's value of register REGNUM |
| 385 | has been saved in memory. Or return zero if it has not been saved. |
| 386 | If REGNUM specifies the SP, the value we return is actually |
| 387 | the SP value, not an address where it was saved. */ |
| 388 | |
| 389 | CORE_ADDR |
| 390 | find_saved_register (frame, regnum) |
| 391 | struct frame_info *frame; |
| 392 | int regnum; |
| 393 | { |
| 394 | struct frame_saved_regs saved_regs; |
| 395 | |
| 396 | register struct frame_info *frame1 = NULL; |
| 397 | register CORE_ADDR addr = 0; |
| 398 | |
| 399 | if (frame == NULL) /* No regs saved if want current frame */ |
| 400 | return 0; |
| 401 | |
| 402 | #ifdef HAVE_REGISTER_WINDOWS |
| 403 | /* We assume that a register in a register window will only be saved |
| 404 | in one place (since the name changes and/or disappears as you go |
| 405 | towards inner frames), so we only call get_frame_saved_regs on |
| 406 | the current frame. This is directly in contradiction to the |
| 407 | usage below, which assumes that registers used in a frame must be |
| 408 | saved in a lower (more interior) frame. This change is a result |
| 409 | of working on a register window machine; get_frame_saved_regs |
| 410 | always returns the registers saved within a frame, within the |
| 411 | context (register namespace) of that frame. */ |
| 412 | |
| 413 | /* However, note that we don't want this to return anything if |
| 414 | nothing is saved (if there's a frame inside of this one). Also, |
| 415 | callers to this routine asking for the stack pointer want the |
| 416 | stack pointer saved for *this* frame; this is returned from the |
| 417 | next frame. */ |
| 418 | |
| 419 | if (REGISTER_IN_WINDOW_P(regnum)) |
| 420 | { |
| 421 | frame1 = get_next_frame (frame); |
| 422 | if (!frame1) return 0; /* Registers of this frame are active. */ |
| 423 | |
| 424 | /* Get the SP from the next frame in; it will be this |
| 425 | current frame. */ |
| 426 | if (regnum != SP_REGNUM) |
| 427 | frame1 = frame; |
| 428 | |
| 429 | get_frame_saved_regs (frame1, &saved_regs); |
| 430 | return saved_regs.regs[regnum]; /* ... which might be zero */ |
| 431 | } |
| 432 | #endif /* HAVE_REGISTER_WINDOWS */ |
| 433 | |
| 434 | /* Note that this next routine assumes that registers used in |
| 435 | frame x will be saved only in the frame that x calls and |
| 436 | frames interior to it. This is not true on the sparc, but the |
| 437 | above macro takes care of it, so we should be all right. */ |
| 438 | while (1) |
| 439 | { |
| 440 | QUIT; |
| 441 | frame1 = get_prev_frame (frame1); |
| 442 | if (frame1 == 0 || frame1 == frame) |
| 443 | break; |
| 444 | get_frame_saved_regs (frame1, &saved_regs); |
| 445 | if (saved_regs.regs[regnum]) |
| 446 | addr = saved_regs.regs[regnum]; |
| 447 | } |
| 448 | |
| 449 | return addr; |
| 450 | } |
| 451 | |
| 452 | /* Find register number REGNUM relative to FRAME and put its (raw, |
| 453 | target format) contents in *RAW_BUFFER. Set *OPTIMIZED if the |
| 454 | variable was optimized out (and thus can't be fetched). Set *LVAL |
| 455 | to lval_memory, lval_register, or not_lval, depending on whether |
| 456 | the value was fetched from memory, from a register, or in a strange |
| 457 | and non-modifiable way (e.g. a frame pointer which was calculated |
| 458 | rather than fetched). Set *ADDRP to the address, either in memory |
| 459 | on as a REGISTER_BYTE offset into the registers array. |
| 460 | |
| 461 | Note that this implementation never sets *LVAL to not_lval. But |
| 462 | it can be replaced by defining GET_SAVED_REGISTER and supplying |
| 463 | your own. |
| 464 | |
| 465 | The argument RAW_BUFFER must point to aligned memory. */ |
| 466 | |
| 467 | void |
| 468 | get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval) |
| 469 | char *raw_buffer; |
| 470 | int *optimized; |
| 471 | CORE_ADDR *addrp; |
| 472 | struct frame_info *frame; |
| 473 | int regnum; |
| 474 | enum lval_type *lval; |
| 475 | { |
| 476 | CORE_ADDR addr; |
| 477 | |
| 478 | if (!target_has_registers) |
| 479 | error ("No registers."); |
| 480 | |
| 481 | /* Normal systems don't optimize out things with register numbers. */ |
| 482 | if (optimized != NULL) |
| 483 | *optimized = 0; |
| 484 | addr = find_saved_register (frame, regnum); |
| 485 | if (addr != 0) |
| 486 | { |
| 487 | if (lval != NULL) |
| 488 | *lval = lval_memory; |
| 489 | if (regnum == SP_REGNUM) |
| 490 | { |
| 491 | if (raw_buffer != NULL) |
| 492 | { |
| 493 | /* Put it back in target format. */ |
| 494 | store_address (raw_buffer, REGISTER_RAW_SIZE (regnum), addr); |
| 495 | } |
| 496 | if (addrp != NULL) |
| 497 | *addrp = 0; |
| 498 | return; |
| 499 | } |
| 500 | if (raw_buffer != NULL) |
| 501 | read_memory (addr, raw_buffer, REGISTER_RAW_SIZE (regnum)); |
| 502 | } |
| 503 | else |
| 504 | { |
| 505 | if (lval != NULL) |
| 506 | *lval = lval_register; |
| 507 | addr = REGISTER_BYTE (regnum); |
| 508 | if (raw_buffer != NULL) |
| 509 | read_register_gen (regnum, raw_buffer); |
| 510 | } |
| 511 | if (addrp != NULL) |
| 512 | *addrp = addr; |
| 513 | } |
| 514 | #endif /* GET_SAVED_REGISTER. */ |
| 515 | |
| 516 | /* Copy the bytes of register REGNUM, relative to the current stack frame, |
| 517 | into our memory at MYADDR, in target byte order. |
| 518 | The number of bytes copied is REGISTER_RAW_SIZE (REGNUM). |
| 519 | |
| 520 | Returns 1 if could not be read, 0 if could. */ |
| 521 | |
| 522 | int |
| 523 | read_relative_register_raw_bytes (regnum, myaddr) |
| 524 | int regnum; |
| 525 | char *myaddr; |
| 526 | { |
| 527 | int optim; |
| 528 | if (regnum == FP_REGNUM && selected_frame) |
| 529 | { |
| 530 | /* Put it back in target format. */ |
| 531 | store_address (myaddr, REGISTER_RAW_SIZE(FP_REGNUM), |
| 532 | FRAME_FP(selected_frame)); |
| 533 | return 0; |
| 534 | } |
| 535 | |
| 536 | get_saved_register (myaddr, &optim, (CORE_ADDR *) NULL, selected_frame, |
| 537 | regnum, (enum lval_type *)NULL); |
| 538 | return optim; |
| 539 | } |
| 540 | |
| 541 | /* Return a `value' with the contents of register REGNUM |
| 542 | in its virtual format, with the type specified by |
| 543 | REGISTER_VIRTUAL_TYPE. */ |
| 544 | |
| 545 | value_ptr |
| 546 | value_of_register (regnum) |
| 547 | int regnum; |
| 548 | { |
| 549 | CORE_ADDR addr; |
| 550 | int optim; |
| 551 | register value_ptr reg_val; |
| 552 | char raw_buffer[MAX_REGISTER_RAW_SIZE]; |
| 553 | enum lval_type lval; |
| 554 | |
| 555 | get_saved_register (raw_buffer, &optim, &addr, |
| 556 | selected_frame, regnum, &lval); |
| 557 | |
| 558 | reg_val = allocate_value (REGISTER_VIRTUAL_TYPE (regnum)); |
| 559 | |
| 560 | /* Convert raw data to virtual format if necessary. */ |
| 561 | |
| 562 | #ifdef REGISTER_CONVERTIBLE |
| 563 | if (REGISTER_CONVERTIBLE (regnum)) |
| 564 | { |
| 565 | REGISTER_CONVERT_TO_VIRTUAL (regnum, REGISTER_VIRTUAL_TYPE (regnum), |
| 566 | raw_buffer, VALUE_CONTENTS_RAW (reg_val)); |
| 567 | } |
| 568 | else |
| 569 | #endif |
| 570 | memcpy (VALUE_CONTENTS_RAW (reg_val), raw_buffer, |
| 571 | REGISTER_RAW_SIZE (regnum)); |
| 572 | VALUE_LVAL (reg_val) = lval; |
| 573 | VALUE_ADDRESS (reg_val) = addr; |
| 574 | VALUE_REGNO (reg_val) = regnum; |
| 575 | VALUE_OPTIMIZED_OUT (reg_val) = optim; |
| 576 | return reg_val; |
| 577 | } |
| 578 | \f |
| 579 | /* Low level examining and depositing of registers. |
| 580 | |
| 581 | The caller is responsible for making |
| 582 | sure that the inferior is stopped before calling the fetching routines, |
| 583 | or it will get garbage. (a change from GDB version 3, in which |
| 584 | the caller got the value from the last stop). */ |
| 585 | |
| 586 | /* Contents of the registers in target byte order. |
| 587 | We allocate some extra slop since we do a lot of memcpy's around `registers', |
| 588 | and failing-soft is better than failing hard. */ |
| 589 | char registers[REGISTER_BYTES + /* SLOP */ 256]; |
| 590 | |
| 591 | /* Nonzero if that register has been fetched. */ |
| 592 | char register_valid[NUM_REGS]; |
| 593 | |
| 594 | /* The thread/process associated with the current set of registers. For now, |
| 595 | -1 is special, and means `no current process'. */ |
| 596 | int registers_pid = -1; |
| 597 | |
| 598 | /* Indicate that registers may have changed, so invalidate the cache. */ |
| 599 | |
| 600 | void |
| 601 | registers_changed () |
| 602 | { |
| 603 | int i; |
| 604 | int numregs = ARCH_NUM_REGS; |
| 605 | |
| 606 | registers_pid = -1; |
| 607 | |
| 608 | for (i = 0; i < numregs; i++) |
| 609 | register_valid[i] = 0; |
| 610 | |
| 611 | if (registers_changed_hook) |
| 612 | registers_changed_hook (); |
| 613 | } |
| 614 | |
| 615 | /* Indicate that all registers have been fetched, so mark them all valid. */ |
| 616 | void |
| 617 | registers_fetched () |
| 618 | { |
| 619 | int i; |
| 620 | int numregs = ARCH_NUM_REGS; |
| 621 | for (i = 0; i < numregs; i++) |
| 622 | register_valid[i] = 1; |
| 623 | } |
| 624 | |
| 625 | /* read_register_bytes and write_register_bytes are generally a *BAD* idea. |
| 626 | They are inefficient because they need to check for partial updates, which |
| 627 | can only be done by scanning through all of the registers and seeing if the |
| 628 | bytes that are being read/written fall inside of an invalid register. [The |
| 629 | main reason this is necessary is that register sizes can vary, so a simple |
| 630 | index won't suffice.] It is far better to call read_register_gen if you |
| 631 | want to get at the raw register contents, as it only takes a regno as an |
| 632 | argument, and therefore can't do a partial register update. It would also |
| 633 | be good to have a write_register_gen for similar reasons. |
| 634 | |
| 635 | Prior to the recent fixes to check for partial updates, both read and |
| 636 | write_register_bytes always checked to see if any registers were stale, and |
| 637 | then called target_fetch_registers (-1) to update the whole set. This |
| 638 | caused really slowed things down for remote targets. */ |
| 639 | |
| 640 | /* Copy INLEN bytes of consecutive data from registers |
| 641 | starting with the INREGBYTE'th byte of register data |
| 642 | into memory at MYADDR. */ |
| 643 | |
| 644 | void |
| 645 | read_register_bytes (inregbyte, myaddr, inlen) |
| 646 | int inregbyte; |
| 647 | char *myaddr; |
| 648 | int inlen; |
| 649 | { |
| 650 | int inregend = inregbyte + inlen; |
| 651 | int regno; |
| 652 | |
| 653 | if (registers_pid != inferior_pid) |
| 654 | { |
| 655 | registers_changed (); |
| 656 | registers_pid = inferior_pid; |
| 657 | } |
| 658 | |
| 659 | /* See if we are trying to read bytes from out-of-date registers. If so, |
| 660 | update just those registers. */ |
| 661 | |
| 662 | for (regno = 0; regno < NUM_REGS; regno++) |
| 663 | { |
| 664 | int regstart, regend; |
| 665 | int startin, endin; |
| 666 | |
| 667 | if (register_valid[regno]) |
| 668 | continue; |
| 669 | |
| 670 | regstart = REGISTER_BYTE (regno); |
| 671 | regend = regstart + REGISTER_RAW_SIZE (regno); |
| 672 | |
| 673 | startin = regstart >= inregbyte && regstart < inregend; |
| 674 | endin = regend > inregbyte && regend <= inregend; |
| 675 | |
| 676 | if (!startin && !endin) |
| 677 | continue; |
| 678 | |
| 679 | /* We've found an invalid register where at least one byte will be read. |
| 680 | Update it from the target. */ |
| 681 | |
| 682 | target_fetch_registers (regno); |
| 683 | |
| 684 | if (!register_valid[regno]) |
| 685 | error ("read_register_bytes: Couldn't update register %d.", regno); |
| 686 | } |
| 687 | |
| 688 | if (myaddr != NULL) |
| 689 | memcpy (myaddr, ®isters[inregbyte], inlen); |
| 690 | } |
| 691 | |
| 692 | /* Read register REGNO into memory at MYADDR, which must be large enough |
| 693 | for REGISTER_RAW_BYTES (REGNO). Target byte-order. |
| 694 | If the register is known to be the size of a CORE_ADDR or smaller, |
| 695 | read_register can be used instead. */ |
| 696 | void |
| 697 | read_register_gen (regno, myaddr) |
| 698 | int regno; |
| 699 | char *myaddr; |
| 700 | { |
| 701 | if (registers_pid != inferior_pid) |
| 702 | { |
| 703 | registers_changed (); |
| 704 | registers_pid = inferior_pid; |
| 705 | } |
| 706 | |
| 707 | if (!register_valid[regno]) |
| 708 | target_fetch_registers (regno); |
| 709 | memcpy (myaddr, ®isters[REGISTER_BYTE (regno)], |
| 710 | REGISTER_RAW_SIZE (regno)); |
| 711 | } |
| 712 | |
| 713 | /* Write register REGNO at MYADDR to the target. MYADDR points at |
| 714 | REGISTER_RAW_BYTES(REGNO), which must be in target byte-order. */ |
| 715 | |
| 716 | void |
| 717 | write_register_gen (regno, myaddr) |
| 718 | int regno; |
| 719 | char *myaddr; |
| 720 | { |
| 721 | int size; |
| 722 | |
| 723 | /* On the sparc, writing %g0 is a no-op, so we don't even want to change |
| 724 | the registers array if something writes to this register. */ |
| 725 | if (CANNOT_STORE_REGISTER (regno)) |
| 726 | return; |
| 727 | |
| 728 | if (registers_pid != inferior_pid) |
| 729 | { |
| 730 | registers_changed (); |
| 731 | registers_pid = inferior_pid; |
| 732 | } |
| 733 | |
| 734 | size = REGISTER_RAW_SIZE(regno); |
| 735 | |
| 736 | /* If we have a valid copy of the register, and new value == old value, |
| 737 | then don't bother doing the actual store. */ |
| 738 | |
| 739 | if (register_valid [regno] |
| 740 | && memcmp (®isters[REGISTER_BYTE (regno)], myaddr, size) == 0) |
| 741 | return; |
| 742 | |
| 743 | target_prepare_to_store (); |
| 744 | |
| 745 | memcpy (®isters[REGISTER_BYTE (regno)], myaddr, size); |
| 746 | |
| 747 | register_valid [regno] = 1; |
| 748 | |
| 749 | target_store_registers (regno); |
| 750 | } |
| 751 | |
| 752 | /* Copy INLEN bytes of consecutive data from memory at MYADDR |
| 753 | into registers starting with the MYREGSTART'th byte of register data. */ |
| 754 | |
| 755 | void |
| 756 | write_register_bytes (myregstart, myaddr, inlen) |
| 757 | int myregstart; |
| 758 | char *myaddr; |
| 759 | int inlen; |
| 760 | { |
| 761 | int myregend = myregstart + inlen; |
| 762 | int regno; |
| 763 | |
| 764 | target_prepare_to_store (); |
| 765 | |
| 766 | /* Scan through the registers updating any that are covered by the range |
| 767 | myregstart<=>myregend using write_register_gen, which does nice things |
| 768 | like handling threads, and avoiding updates when the new and old contents |
| 769 | are the same. */ |
| 770 | |
| 771 | for (regno = 0; regno < NUM_REGS; regno++) |
| 772 | { |
| 773 | int regstart, regend; |
| 774 | int startin, endin; |
| 775 | char regbuf[MAX_REGISTER_RAW_SIZE]; |
| 776 | |
| 777 | regstart = REGISTER_BYTE (regno); |
| 778 | regend = regstart + REGISTER_RAW_SIZE (regno); |
| 779 | |
| 780 | startin = regstart >= myregstart && regstart < myregend; |
| 781 | endin = regend > myregstart && regend <= myregend; |
| 782 | |
| 783 | if (!startin && !endin) |
| 784 | continue; /* Register is completely out of range */ |
| 785 | |
| 786 | if (startin && endin) /* register is completely in range */ |
| 787 | { |
| 788 | write_register_gen (regno, myaddr + (regstart - myregstart)); |
| 789 | continue; |
| 790 | } |
| 791 | |
| 792 | /* We may be doing a partial update of an invalid register. Update it |
| 793 | from the target before scribbling on it. */ |
| 794 | read_register_gen (regno, regbuf); |
| 795 | |
| 796 | if (startin) |
| 797 | memcpy (registers + regstart, |
| 798 | myaddr + regstart - myregstart, |
| 799 | myregend - regstart); |
| 800 | else /* endin */ |
| 801 | memcpy (registers + myregstart, |
| 802 | myaddr, |
| 803 | regend - myregstart); |
| 804 | target_store_registers (regno); |
| 805 | } |
| 806 | } |
| 807 | |
| 808 | /* Return the raw contents of register REGNO, regarding it as an integer. */ |
| 809 | /* This probably should be returning LONGEST rather than CORE_ADDR. */ |
| 810 | |
| 811 | CORE_ADDR |
| 812 | read_register (regno) |
| 813 | int regno; |
| 814 | { |
| 815 | if (registers_pid != inferior_pid) |
| 816 | { |
| 817 | registers_changed (); |
| 818 | registers_pid = inferior_pid; |
| 819 | } |
| 820 | |
| 821 | if (!register_valid[regno]) |
| 822 | target_fetch_registers (regno); |
| 823 | |
| 824 | return extract_address (®isters[REGISTER_BYTE (regno)], |
| 825 | REGISTER_RAW_SIZE(regno)); |
| 826 | } |
| 827 | |
| 828 | CORE_ADDR |
| 829 | read_register_pid (regno, pid) |
| 830 | int regno, pid; |
| 831 | { |
| 832 | int save_pid; |
| 833 | CORE_ADDR retval; |
| 834 | |
| 835 | if (pid == inferior_pid) |
| 836 | return read_register (regno); |
| 837 | |
| 838 | save_pid = inferior_pid; |
| 839 | |
| 840 | inferior_pid = pid; |
| 841 | |
| 842 | retval = read_register (regno); |
| 843 | |
| 844 | inferior_pid = save_pid; |
| 845 | |
| 846 | return retval; |
| 847 | } |
| 848 | |
| 849 | /* Store VALUE, into the raw contents of register number REGNO. */ |
| 850 | |
| 851 | void |
| 852 | write_register (regno, val) |
| 853 | int regno; |
| 854 | LONGEST val; |
| 855 | { |
| 856 | PTR buf; |
| 857 | int size; |
| 858 | |
| 859 | /* On the sparc, writing %g0 is a no-op, so we don't even want to change |
| 860 | the registers array if something writes to this register. */ |
| 861 | if (CANNOT_STORE_REGISTER (regno)) |
| 862 | return; |
| 863 | |
| 864 | if (registers_pid != inferior_pid) |
| 865 | { |
| 866 | registers_changed (); |
| 867 | registers_pid = inferior_pid; |
| 868 | } |
| 869 | |
| 870 | size = REGISTER_RAW_SIZE(regno); |
| 871 | buf = alloca (size); |
| 872 | store_signed_integer (buf, size, (LONGEST) val); |
| 873 | |
| 874 | /* If we have a valid copy of the register, and new value == old value, |
| 875 | then don't bother doing the actual store. */ |
| 876 | |
| 877 | if (register_valid [regno] |
| 878 | && memcmp (®isters[REGISTER_BYTE (regno)], buf, size) == 0) |
| 879 | return; |
| 880 | |
| 881 | target_prepare_to_store (); |
| 882 | |
| 883 | memcpy (®isters[REGISTER_BYTE (regno)], buf, size); |
| 884 | |
| 885 | register_valid [regno] = 1; |
| 886 | |
| 887 | target_store_registers (regno); |
| 888 | } |
| 889 | |
| 890 | static void |
| 891 | write_register_pid (regno, val, pid) |
| 892 | int regno; |
| 893 | LONGEST val; |
| 894 | int pid; |
| 895 | { |
| 896 | int save_pid; |
| 897 | |
| 898 | if (pid == inferior_pid) |
| 899 | { |
| 900 | write_register (regno, val); |
| 901 | return; |
| 902 | } |
| 903 | |
| 904 | save_pid = inferior_pid; |
| 905 | |
| 906 | inferior_pid = pid; |
| 907 | |
| 908 | write_register (regno, val); |
| 909 | |
| 910 | inferior_pid = save_pid; |
| 911 | } |
| 912 | |
| 913 | /* Record that register REGNO contains VAL. |
| 914 | This is used when the value is obtained from the inferior or core dump, |
| 915 | so there is no need to store the value there. */ |
| 916 | |
| 917 | void |
| 918 | supply_register (regno, val) |
| 919 | int regno; |
| 920 | char *val; |
| 921 | { |
| 922 | if (registers_pid != inferior_pid) |
| 923 | { |
| 924 | registers_changed (); |
| 925 | registers_pid = inferior_pid; |
| 926 | } |
| 927 | |
| 928 | register_valid[regno] = 1; |
| 929 | memcpy (®isters[REGISTER_BYTE (regno)], val, REGISTER_RAW_SIZE (regno)); |
| 930 | |
| 931 | /* On some architectures, e.g. HPPA, there are a few stray bits in some |
| 932 | registers, that the rest of the code would like to ignore. */ |
| 933 | #ifdef CLEAN_UP_REGISTER_VALUE |
| 934 | CLEAN_UP_REGISTER_VALUE(regno, ®isters[REGISTER_BYTE(regno)]); |
| 935 | #endif |
| 936 | } |
| 937 | |
| 938 | |
| 939 | /* This routine is getting awfully cluttered with #if's. It's probably |
| 940 | time to turn this into READ_PC and define it in the tm.h file. |
| 941 | Ditto for write_pc. */ |
| 942 | |
| 943 | CORE_ADDR |
| 944 | read_pc () |
| 945 | { |
| 946 | #ifdef TARGET_READ_PC |
| 947 | return TARGET_READ_PC (inferior_pid); |
| 948 | #else |
| 949 | return ADDR_BITS_REMOVE ((CORE_ADDR) read_register_pid (PC_REGNUM, inferior_pid)); |
| 950 | #endif |
| 951 | } |
| 952 | |
| 953 | CORE_ADDR |
| 954 | read_pc_pid (pid) |
| 955 | int pid; |
| 956 | { |
| 957 | #ifdef TARGET_READ_PC |
| 958 | return TARGET_READ_PC (pid); |
| 959 | #else |
| 960 | return ADDR_BITS_REMOVE ((CORE_ADDR) read_register_pid (PC_REGNUM, pid)); |
| 961 | #endif |
| 962 | } |
| 963 | |
| 964 | void |
| 965 | write_pc (val) |
| 966 | CORE_ADDR val; |
| 967 | { |
| 968 | #ifdef TARGET_WRITE_PC |
| 969 | TARGET_WRITE_PC (val, inferior_pid); |
| 970 | #else |
| 971 | write_register_pid (PC_REGNUM, val, inferior_pid); |
| 972 | #ifdef NPC_REGNUM |
| 973 | write_register_pid (NPC_REGNUM, val + 4, inferior_pid); |
| 974 | #ifdef NNPC_REGNUM |
| 975 | write_register_pid (NNPC_REGNUM, val + 8, inferior_pid); |
| 976 | #endif |
| 977 | #endif |
| 978 | #endif |
| 979 | } |
| 980 | |
| 981 | void |
| 982 | write_pc_pid (val, pid) |
| 983 | CORE_ADDR val; |
| 984 | int pid; |
| 985 | { |
| 986 | #ifdef TARGET_WRITE_PC |
| 987 | TARGET_WRITE_PC (val, pid); |
| 988 | #else |
| 989 | write_register_pid (PC_REGNUM, val, pid); |
| 990 | #ifdef NPC_REGNUM |
| 991 | write_register_pid (NPC_REGNUM, val + 4, pid); |
| 992 | #ifdef NNPC_REGNUM |
| 993 | write_register_pid (NNPC_REGNUM, val + 8, pid); |
| 994 | #endif |
| 995 | #endif |
| 996 | #endif |
| 997 | } |
| 998 | |
| 999 | /* Cope with strage ways of getting to the stack and frame pointers */ |
| 1000 | |
| 1001 | CORE_ADDR |
| 1002 | read_sp () |
| 1003 | { |
| 1004 | #ifdef TARGET_READ_SP |
| 1005 | return TARGET_READ_SP (); |
| 1006 | #else |
| 1007 | return read_register (SP_REGNUM); |
| 1008 | #endif |
| 1009 | } |
| 1010 | |
| 1011 | void |
| 1012 | write_sp (val) |
| 1013 | CORE_ADDR val; |
| 1014 | { |
| 1015 | #ifdef TARGET_WRITE_SP |
| 1016 | TARGET_WRITE_SP (val); |
| 1017 | #else |
| 1018 | write_register (SP_REGNUM, val); |
| 1019 | #endif |
| 1020 | } |
| 1021 | |
| 1022 | CORE_ADDR |
| 1023 | read_fp () |
| 1024 | { |
| 1025 | #ifdef TARGET_READ_FP |
| 1026 | return TARGET_READ_FP (); |
| 1027 | #else |
| 1028 | return read_register (FP_REGNUM); |
| 1029 | #endif |
| 1030 | } |
| 1031 | |
| 1032 | void |
| 1033 | write_fp (val) |
| 1034 | CORE_ADDR val; |
| 1035 | { |
| 1036 | #ifdef TARGET_WRITE_FP |
| 1037 | TARGET_WRITE_FP (val); |
| 1038 | #else |
| 1039 | write_register (FP_REGNUM, val); |
| 1040 | #endif |
| 1041 | } |
| 1042 | \f |
| 1043 | /* Will calling read_var_value or locate_var_value on SYM end |
| 1044 | up caring what frame it is being evaluated relative to? SYM must |
| 1045 | be non-NULL. */ |
| 1046 | int |
| 1047 | symbol_read_needs_frame (sym) |
| 1048 | struct symbol *sym; |
| 1049 | { |
| 1050 | switch (SYMBOL_CLASS (sym)) |
| 1051 | { |
| 1052 | /* All cases listed explicitly so that gcc -Wall will detect it if |
| 1053 | we failed to consider one. */ |
| 1054 | case LOC_REGISTER: |
| 1055 | case LOC_ARG: |
| 1056 | case LOC_REF_ARG: |
| 1057 | case LOC_REGPARM: |
| 1058 | case LOC_REGPARM_ADDR: |
| 1059 | case LOC_LOCAL: |
| 1060 | case LOC_LOCAL_ARG: |
| 1061 | case LOC_BASEREG: |
| 1062 | case LOC_BASEREG_ARG: |
| 1063 | return 1; |
| 1064 | |
| 1065 | case LOC_UNDEF: |
| 1066 | case LOC_CONST: |
| 1067 | case LOC_STATIC: |
| 1068 | case LOC_TYPEDEF: |
| 1069 | |
| 1070 | case LOC_LABEL: |
| 1071 | /* Getting the address of a label can be done independently of the block, |
| 1072 | even if some *uses* of that address wouldn't work so well without |
| 1073 | the right frame. */ |
| 1074 | |
| 1075 | case LOC_BLOCK: |
| 1076 | case LOC_CONST_BYTES: |
| 1077 | case LOC_UNRESOLVED: |
| 1078 | case LOC_OPTIMIZED_OUT: |
| 1079 | return 0; |
| 1080 | } |
| 1081 | return 1; |
| 1082 | } |
| 1083 | |
| 1084 | /* Given a struct symbol for a variable, |
| 1085 | and a stack frame id, read the value of the variable |
| 1086 | and return a (pointer to a) struct value containing the value. |
| 1087 | If the variable cannot be found, return a zero pointer. |
| 1088 | If FRAME is NULL, use the selected_frame. */ |
| 1089 | |
| 1090 | value_ptr |
| 1091 | read_var_value (var, frame) |
| 1092 | register struct symbol *var; |
| 1093 | struct frame_info *frame; |
| 1094 | { |
| 1095 | register value_ptr v; |
| 1096 | struct type *type = SYMBOL_TYPE (var); |
| 1097 | CORE_ADDR addr; |
| 1098 | register int len; |
| 1099 | |
| 1100 | v = allocate_value (type); |
| 1101 | VALUE_LVAL (v) = lval_memory; /* The most likely possibility. */ |
| 1102 | len = TYPE_LENGTH (type); |
| 1103 | |
| 1104 | if (frame == NULL) frame = selected_frame; |
| 1105 | |
| 1106 | switch (SYMBOL_CLASS (var)) |
| 1107 | { |
| 1108 | case LOC_CONST: |
| 1109 | /* Put the constant back in target format. */ |
| 1110 | store_signed_integer (VALUE_CONTENTS_RAW (v), len, |
| 1111 | (LONGEST) SYMBOL_VALUE (var)); |
| 1112 | VALUE_LVAL (v) = not_lval; |
| 1113 | return v; |
| 1114 | |
| 1115 | case LOC_LABEL: |
| 1116 | /* Put the constant back in target format. */ |
| 1117 | store_address (VALUE_CONTENTS_RAW (v), len, SYMBOL_VALUE_ADDRESS (var)); |
| 1118 | VALUE_LVAL (v) = not_lval; |
| 1119 | return v; |
| 1120 | |
| 1121 | case LOC_CONST_BYTES: |
| 1122 | { |
| 1123 | char *bytes_addr; |
| 1124 | bytes_addr = SYMBOL_VALUE_BYTES (var); |
| 1125 | memcpy (VALUE_CONTENTS_RAW (v), bytes_addr, len); |
| 1126 | VALUE_LVAL (v) = not_lval; |
| 1127 | return v; |
| 1128 | } |
| 1129 | |
| 1130 | case LOC_STATIC: |
| 1131 | addr = SYMBOL_VALUE_ADDRESS (var); |
| 1132 | break; |
| 1133 | |
| 1134 | case LOC_ARG: |
| 1135 | if (frame == NULL) |
| 1136 | return 0; |
| 1137 | addr = FRAME_ARGS_ADDRESS (frame); |
| 1138 | if (!addr) |
| 1139 | return 0; |
| 1140 | addr += SYMBOL_VALUE (var); |
| 1141 | break; |
| 1142 | |
| 1143 | case LOC_REF_ARG: |
| 1144 | if (frame == NULL) |
| 1145 | return 0; |
| 1146 | addr = FRAME_ARGS_ADDRESS (frame); |
| 1147 | if (!addr) |
| 1148 | return 0; |
| 1149 | addr += SYMBOL_VALUE (var); |
| 1150 | addr = read_memory_unsigned_integer |
| 1151 | (addr, TARGET_PTR_BIT / TARGET_CHAR_BIT); |
| 1152 | break; |
| 1153 | |
| 1154 | case LOC_LOCAL: |
| 1155 | case LOC_LOCAL_ARG: |
| 1156 | if (frame == NULL) |
| 1157 | return 0; |
| 1158 | addr = FRAME_LOCALS_ADDRESS (frame); |
| 1159 | addr += SYMBOL_VALUE (var); |
| 1160 | break; |
| 1161 | |
| 1162 | case LOC_BASEREG: |
| 1163 | case LOC_BASEREG_ARG: |
| 1164 | { |
| 1165 | char buf[MAX_REGISTER_RAW_SIZE]; |
| 1166 | get_saved_register (buf, NULL, NULL, frame, SYMBOL_BASEREG (var), |
| 1167 | NULL); |
| 1168 | addr = extract_address (buf, REGISTER_RAW_SIZE (SYMBOL_BASEREG (var))); |
| 1169 | addr += SYMBOL_VALUE (var); |
| 1170 | break; |
| 1171 | } |
| 1172 | |
| 1173 | case LOC_TYPEDEF: |
| 1174 | error ("Cannot look up value of a typedef"); |
| 1175 | break; |
| 1176 | |
| 1177 | case LOC_BLOCK: |
| 1178 | VALUE_ADDRESS (v) = BLOCK_START (SYMBOL_BLOCK_VALUE (var)); |
| 1179 | return v; |
| 1180 | |
| 1181 | case LOC_REGISTER: |
| 1182 | case LOC_REGPARM: |
| 1183 | case LOC_REGPARM_ADDR: |
| 1184 | { |
| 1185 | struct block *b; |
| 1186 | |
| 1187 | if (frame == NULL) |
| 1188 | return 0; |
| 1189 | b = get_frame_block (frame); |
| 1190 | |
| 1191 | |
| 1192 | if (SYMBOL_CLASS (var) == LOC_REGPARM_ADDR) |
| 1193 | { |
| 1194 | addr = |
| 1195 | value_as_pointer (value_from_register (lookup_pointer_type (type), |
| 1196 | SYMBOL_VALUE (var), |
| 1197 | frame)); |
| 1198 | VALUE_LVAL (v) = lval_memory; |
| 1199 | } |
| 1200 | else |
| 1201 | return value_from_register (type, SYMBOL_VALUE (var), frame); |
| 1202 | } |
| 1203 | break; |
| 1204 | |
| 1205 | case LOC_UNRESOLVED: |
| 1206 | { |
| 1207 | struct minimal_symbol *msym; |
| 1208 | |
| 1209 | msym = lookup_minimal_symbol (SYMBOL_NAME (var), NULL, NULL); |
| 1210 | if (msym == NULL) |
| 1211 | return 0; |
| 1212 | addr = SYMBOL_VALUE_ADDRESS (msym); |
| 1213 | } |
| 1214 | break; |
| 1215 | |
| 1216 | case LOC_OPTIMIZED_OUT: |
| 1217 | VALUE_LVAL (v) = not_lval; |
| 1218 | VALUE_OPTIMIZED_OUT (v) = 1; |
| 1219 | return v; |
| 1220 | |
| 1221 | default: |
| 1222 | error ("Cannot look up value of a botched symbol."); |
| 1223 | break; |
| 1224 | } |
| 1225 | |
| 1226 | VALUE_ADDRESS (v) = addr; |
| 1227 | VALUE_LAZY (v) = 1; |
| 1228 | return v; |
| 1229 | } |
| 1230 | |
| 1231 | /* Return a value of type TYPE, stored in register REGNUM, in frame |
| 1232 | FRAME. */ |
| 1233 | |
| 1234 | value_ptr |
| 1235 | value_from_register (type, regnum, frame) |
| 1236 | struct type *type; |
| 1237 | int regnum; |
| 1238 | struct frame_info *frame; |
| 1239 | { |
| 1240 | char raw_buffer [MAX_REGISTER_RAW_SIZE]; |
| 1241 | CORE_ADDR addr; |
| 1242 | int optim; |
| 1243 | value_ptr v = allocate_value (type); |
| 1244 | char *value_bytes = 0; |
| 1245 | int value_bytes_copied = 0; |
| 1246 | int num_storage_locs; |
| 1247 | enum lval_type lval; |
| 1248 | int len; |
| 1249 | |
| 1250 | CHECK_TYPEDEF (type); |
| 1251 | len = TYPE_LENGTH (type); |
| 1252 | |
| 1253 | VALUE_REGNO (v) = regnum; |
| 1254 | |
| 1255 | num_storage_locs = (len > REGISTER_VIRTUAL_SIZE (regnum) ? |
| 1256 | ((len - 1) / REGISTER_RAW_SIZE (regnum)) + 1 : |
| 1257 | 1); |
| 1258 | |
| 1259 | if (num_storage_locs > 1 |
| 1260 | #ifdef GDB_TARGET_IS_H8500 |
| 1261 | || TYPE_CODE (type) == TYPE_CODE_PTR |
| 1262 | #endif |
| 1263 | ) |
| 1264 | { |
| 1265 | /* Value spread across multiple storage locations. */ |
| 1266 | |
| 1267 | int local_regnum; |
| 1268 | int mem_stor = 0, reg_stor = 0; |
| 1269 | int mem_tracking = 1; |
| 1270 | CORE_ADDR last_addr = 0; |
| 1271 | CORE_ADDR first_addr = 0; |
| 1272 | |
| 1273 | value_bytes = (char *) alloca (len + MAX_REGISTER_RAW_SIZE); |
| 1274 | |
| 1275 | /* Copy all of the data out, whereever it may be. */ |
| 1276 | |
| 1277 | #ifdef GDB_TARGET_IS_H8500 |
| 1278 | /* This piece of hideosity is required because the H8500 treats registers |
| 1279 | differently depending upon whether they are used as pointers or not. As a |
| 1280 | pointer, a register needs to have a page register tacked onto the front. |
| 1281 | An alternate way to do this would be to have gcc output different register |
| 1282 | numbers for the pointer & non-pointer form of the register. But, it |
| 1283 | doesn't, so we're stuck with this. */ |
| 1284 | |
| 1285 | if (TYPE_CODE (type) == TYPE_CODE_PTR |
| 1286 | && len > 2) |
| 1287 | { |
| 1288 | int page_regnum; |
| 1289 | |
| 1290 | switch (regnum) |
| 1291 | { |
| 1292 | case R0_REGNUM: case R1_REGNUM: case R2_REGNUM: case R3_REGNUM: |
| 1293 | page_regnum = SEG_D_REGNUM; |
| 1294 | break; |
| 1295 | case R4_REGNUM: case R5_REGNUM: |
| 1296 | page_regnum = SEG_E_REGNUM; |
| 1297 | break; |
| 1298 | case R6_REGNUM: case R7_REGNUM: |
| 1299 | page_regnum = SEG_T_REGNUM; |
| 1300 | break; |
| 1301 | } |
| 1302 | |
| 1303 | value_bytes[0] = 0; |
| 1304 | get_saved_register (value_bytes + 1, |
| 1305 | &optim, |
| 1306 | &addr, |
| 1307 | frame, |
| 1308 | page_regnum, |
| 1309 | &lval); |
| 1310 | |
| 1311 | if (lval == lval_register) |
| 1312 | reg_stor++; |
| 1313 | else |
| 1314 | mem_stor++; |
| 1315 | first_addr = addr; |
| 1316 | last_addr = addr; |
| 1317 | |
| 1318 | get_saved_register (value_bytes + 2, |
| 1319 | &optim, |
| 1320 | &addr, |
| 1321 | frame, |
| 1322 | regnum, |
| 1323 | &lval); |
| 1324 | |
| 1325 | if (lval == lval_register) |
| 1326 | reg_stor++; |
| 1327 | else |
| 1328 | { |
| 1329 | mem_stor++; |
| 1330 | mem_tracking = mem_tracking && (addr == last_addr); |
| 1331 | } |
| 1332 | last_addr = addr; |
| 1333 | } |
| 1334 | else |
| 1335 | #endif /* GDB_TARGET_IS_H8500 */ |
| 1336 | for (local_regnum = regnum; |
| 1337 | value_bytes_copied < len; |
| 1338 | (value_bytes_copied += REGISTER_RAW_SIZE (local_regnum), |
| 1339 | ++local_regnum)) |
| 1340 | { |
| 1341 | get_saved_register (value_bytes + value_bytes_copied, |
| 1342 | &optim, |
| 1343 | &addr, |
| 1344 | frame, |
| 1345 | local_regnum, |
| 1346 | &lval); |
| 1347 | |
| 1348 | if (regnum == local_regnum) |
| 1349 | first_addr = addr; |
| 1350 | if (lval == lval_register) |
| 1351 | reg_stor++; |
| 1352 | else |
| 1353 | { |
| 1354 | mem_stor++; |
| 1355 | |
| 1356 | mem_tracking = |
| 1357 | (mem_tracking |
| 1358 | && (regnum == local_regnum |
| 1359 | || addr == last_addr)); |
| 1360 | } |
| 1361 | last_addr = addr; |
| 1362 | } |
| 1363 | |
| 1364 | if ((reg_stor && mem_stor) |
| 1365 | || (mem_stor && !mem_tracking)) |
| 1366 | /* Mixed storage; all of the hassle we just went through was |
| 1367 | for some good purpose. */ |
| 1368 | { |
| 1369 | VALUE_LVAL (v) = lval_reg_frame_relative; |
| 1370 | VALUE_FRAME (v) = FRAME_FP (frame); |
| 1371 | VALUE_FRAME_REGNUM (v) = regnum; |
| 1372 | } |
| 1373 | else if (mem_stor) |
| 1374 | { |
| 1375 | VALUE_LVAL (v) = lval_memory; |
| 1376 | VALUE_ADDRESS (v) = first_addr; |
| 1377 | } |
| 1378 | else if (reg_stor) |
| 1379 | { |
| 1380 | VALUE_LVAL (v) = lval_register; |
| 1381 | VALUE_ADDRESS (v) = first_addr; |
| 1382 | } |
| 1383 | else |
| 1384 | fatal ("value_from_register: Value not stored anywhere!"); |
| 1385 | |
| 1386 | VALUE_OPTIMIZED_OUT (v) = optim; |
| 1387 | |
| 1388 | /* Any structure stored in more than one register will always be |
| 1389 | an integral number of registers. Otherwise, you'd need to do |
| 1390 | some fiddling with the last register copied here for little |
| 1391 | endian machines. */ |
| 1392 | |
| 1393 | /* Copy into the contents section of the value. */ |
| 1394 | memcpy (VALUE_CONTENTS_RAW (v), value_bytes, len); |
| 1395 | |
| 1396 | /* Finally do any conversion necessary when extracting this |
| 1397 | type from more than one register. */ |
| 1398 | #ifdef REGISTER_CONVERT_TO_TYPE |
| 1399 | REGISTER_CONVERT_TO_TYPE(regnum, type, VALUE_CONTENTS_RAW(v)); |
| 1400 | #endif |
| 1401 | return v; |
| 1402 | } |
| 1403 | |
| 1404 | /* Data is completely contained within a single register. Locate the |
| 1405 | register's contents in a real register or in core; |
| 1406 | read the data in raw format. */ |
| 1407 | |
| 1408 | get_saved_register (raw_buffer, &optim, &addr, frame, regnum, &lval); |
| 1409 | VALUE_OPTIMIZED_OUT (v) = optim; |
| 1410 | VALUE_LVAL (v) = lval; |
| 1411 | VALUE_ADDRESS (v) = addr; |
| 1412 | |
| 1413 | /* Convert raw data to virtual format if necessary. */ |
| 1414 | |
| 1415 | #ifdef REGISTER_CONVERTIBLE |
| 1416 | if (REGISTER_CONVERTIBLE (regnum)) |
| 1417 | { |
| 1418 | REGISTER_CONVERT_TO_VIRTUAL (regnum, type, |
| 1419 | raw_buffer, VALUE_CONTENTS_RAW (v)); |
| 1420 | } |
| 1421 | else |
| 1422 | #endif |
| 1423 | { |
| 1424 | /* Raw and virtual formats are the same for this register. */ |
| 1425 | |
| 1426 | if (TARGET_BYTE_ORDER == BIG_ENDIAN && len < REGISTER_RAW_SIZE (regnum)) |
| 1427 | { |
| 1428 | /* Big-endian, and we want less than full size. */ |
| 1429 | VALUE_OFFSET (v) = REGISTER_RAW_SIZE (regnum) - len; |
| 1430 | } |
| 1431 | |
| 1432 | memcpy (VALUE_CONTENTS_RAW (v), raw_buffer + VALUE_OFFSET (v), len); |
| 1433 | } |
| 1434 | |
| 1435 | return v; |
| 1436 | } |
| 1437 | \f |
| 1438 | /* Given a struct symbol for a variable or function, |
| 1439 | and a stack frame id, |
| 1440 | return a (pointer to a) struct value containing the properly typed |
| 1441 | address. */ |
| 1442 | |
| 1443 | value_ptr |
| 1444 | locate_var_value (var, frame) |
| 1445 | register struct symbol *var; |
| 1446 | struct frame_info *frame; |
| 1447 | { |
| 1448 | CORE_ADDR addr = 0; |
| 1449 | struct type *type = SYMBOL_TYPE (var); |
| 1450 | value_ptr lazy_value; |
| 1451 | |
| 1452 | /* Evaluate it first; if the result is a memory address, we're fine. |
| 1453 | Lazy evaluation pays off here. */ |
| 1454 | |
| 1455 | lazy_value = read_var_value (var, frame); |
| 1456 | if (lazy_value == 0) |
| 1457 | error ("Address of \"%s\" is unknown.", SYMBOL_SOURCE_NAME (var)); |
| 1458 | |
| 1459 | if (VALUE_LAZY (lazy_value) |
| 1460 | || TYPE_CODE (type) == TYPE_CODE_FUNC) |
| 1461 | { |
| 1462 | addr = VALUE_ADDRESS (lazy_value); |
| 1463 | return value_from_longest (lookup_pointer_type (type), (LONGEST) addr); |
| 1464 | } |
| 1465 | |
| 1466 | /* Not a memory address; check what the problem was. */ |
| 1467 | switch (VALUE_LVAL (lazy_value)) |
| 1468 | { |
| 1469 | case lval_register: |
| 1470 | case lval_reg_frame_relative: |
| 1471 | error ("Address requested for identifier \"%s\" which is in a register.", |
| 1472 | SYMBOL_SOURCE_NAME (var)); |
| 1473 | break; |
| 1474 | |
| 1475 | default: |
| 1476 | error ("Can't take address of \"%s\" which isn't an lvalue.", |
| 1477 | SYMBOL_SOURCE_NAME (var)); |
| 1478 | break; |
| 1479 | } |
| 1480 | return 0; /* For lint -- never reached */ |
| 1481 | } |