| 1 | /* Floating point routines for GDB, the GNU debugger. |
| 2 | |
| 3 | Copyright (C) 2017 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "gdbtypes.h" |
| 22 | #include "floatformat.h" |
| 23 | #include "target-float.h" |
| 24 | |
| 25 | |
| 26 | /* Helper routines operating on binary floating-point data. */ |
| 27 | |
| 28 | #include <math.h> |
| 29 | |
| 30 | #if (defined HAVE_LONG_DOUBLE && defined PRINTF_HAS_LONG_DOUBLE \ |
| 31 | && defined SCANF_HAS_LONG_DOUBLE) |
| 32 | typedef long double DOUBLEST; |
| 33 | #else |
| 34 | typedef double DOUBLEST; |
| 35 | /* If we can't scan or print long double, we don't want to use it |
| 36 | anywhere. */ |
| 37 | # undef HAVE_LONG_DOUBLE |
| 38 | # undef PRINTF_HAS_LONG_DOUBLE |
| 39 | # undef SCANF_HAS_LONG_DOUBLE |
| 40 | #endif |
| 41 | |
| 42 | /* Different kinds of floatformat numbers recognized by |
| 43 | floatformat_classify. To avoid portability issues, we use local |
| 44 | values instead of the C99 macros (FP_NAN et cetera). */ |
| 45 | enum float_kind { |
| 46 | float_nan, |
| 47 | float_infinite, |
| 48 | float_zero, |
| 49 | float_normal, |
| 50 | float_subnormal |
| 51 | }; |
| 52 | |
| 53 | /* The odds that CHAR_BIT will be anything but 8 are low enough that I'm not |
| 54 | going to bother with trying to muck around with whether it is defined in |
| 55 | a system header, what we do if not, etc. */ |
| 56 | #define FLOATFORMAT_CHAR_BIT 8 |
| 57 | |
| 58 | /* The number of bytes that the largest floating-point type that we |
| 59 | can convert to doublest will need. */ |
| 60 | #define FLOATFORMAT_LARGEST_BYTES 16 |
| 61 | |
| 62 | /* Return the floatformat's total size in host bytes. */ |
| 63 | static size_t |
| 64 | floatformat_totalsize_bytes (const struct floatformat *fmt) |
| 65 | { |
| 66 | return ((fmt->totalsize + FLOATFORMAT_CHAR_BIT - 1) |
| 67 | / FLOATFORMAT_CHAR_BIT); |
| 68 | } |
| 69 | |
| 70 | /* Return the precision of the floating point format FMT. */ |
| 71 | static int |
| 72 | floatformat_precision (const struct floatformat *fmt) |
| 73 | { |
| 74 | /* Assume the precision of and IBM long double is twice the precision |
| 75 | of the underlying double. This matches what GCC does. */ |
| 76 | if (fmt->split_half) |
| 77 | return 2 * floatformat_precision (fmt->split_half); |
| 78 | |
| 79 | /* Otherwise, the precision is the size of mantissa in bits, |
| 80 | including the implicit bit if present. */ |
| 81 | int prec = fmt->man_len; |
| 82 | if (fmt->intbit == floatformat_intbit_no) |
| 83 | prec++; |
| 84 | |
| 85 | return prec; |
| 86 | } |
| 87 | |
| 88 | /* Normalize the byte order of FROM into TO. If no normalization is |
| 89 | needed then FMT->byteorder is returned and TO is not changed; |
| 90 | otherwise the format of the normalized form in TO is returned. */ |
| 91 | static enum floatformat_byteorders |
| 92 | floatformat_normalize_byteorder (const struct floatformat *fmt, |
| 93 | const void *from, void *to) |
| 94 | { |
| 95 | const unsigned char *swapin; |
| 96 | unsigned char *swapout; |
| 97 | int words; |
| 98 | |
| 99 | if (fmt->byteorder == floatformat_little |
| 100 | || fmt->byteorder == floatformat_big) |
| 101 | return fmt->byteorder; |
| 102 | |
| 103 | words = fmt->totalsize / FLOATFORMAT_CHAR_BIT; |
| 104 | words >>= 2; |
| 105 | |
| 106 | swapout = (unsigned char *)to; |
| 107 | swapin = (const unsigned char *)from; |
| 108 | |
| 109 | if (fmt->byteorder == floatformat_vax) |
| 110 | { |
| 111 | while (words-- > 0) |
| 112 | { |
| 113 | *swapout++ = swapin[1]; |
| 114 | *swapout++ = swapin[0]; |
| 115 | *swapout++ = swapin[3]; |
| 116 | *swapout++ = swapin[2]; |
| 117 | swapin += 4; |
| 118 | } |
| 119 | /* This may look weird, since VAX is little-endian, but it is |
| 120 | easier to translate to big-endian than to little-endian. */ |
| 121 | return floatformat_big; |
| 122 | } |
| 123 | else |
| 124 | { |
| 125 | gdb_assert (fmt->byteorder == floatformat_littlebyte_bigword); |
| 126 | |
| 127 | while (words-- > 0) |
| 128 | { |
| 129 | *swapout++ = swapin[3]; |
| 130 | *swapout++ = swapin[2]; |
| 131 | *swapout++ = swapin[1]; |
| 132 | *swapout++ = swapin[0]; |
| 133 | swapin += 4; |
| 134 | } |
| 135 | return floatformat_big; |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | /* Extract a field which starts at START and is LEN bytes long. DATA and |
| 140 | TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */ |
| 141 | static unsigned long |
| 142 | get_field (const bfd_byte *data, enum floatformat_byteorders order, |
| 143 | unsigned int total_len, unsigned int start, unsigned int len) |
| 144 | { |
| 145 | unsigned long result; |
| 146 | unsigned int cur_byte; |
| 147 | int cur_bitshift; |
| 148 | |
| 149 | /* Caller must byte-swap words before calling this routine. */ |
| 150 | gdb_assert (order == floatformat_little || order == floatformat_big); |
| 151 | |
| 152 | /* Start at the least significant part of the field. */ |
| 153 | if (order == floatformat_little) |
| 154 | { |
| 155 | /* We start counting from the other end (i.e, from the high bytes |
| 156 | rather than the low bytes). As such, we need to be concerned |
| 157 | with what happens if bit 0 doesn't start on a byte boundary. |
| 158 | I.e, we need to properly handle the case where total_len is |
| 159 | not evenly divisible by 8. So we compute ``excess'' which |
| 160 | represents the number of bits from the end of our starting |
| 161 | byte needed to get to bit 0. */ |
| 162 | int excess = FLOATFORMAT_CHAR_BIT - (total_len % FLOATFORMAT_CHAR_BIT); |
| 163 | |
| 164 | cur_byte = (total_len / FLOATFORMAT_CHAR_BIT) |
| 165 | - ((start + len + excess) / FLOATFORMAT_CHAR_BIT); |
| 166 | cur_bitshift = ((start + len + excess) % FLOATFORMAT_CHAR_BIT) |
| 167 | - FLOATFORMAT_CHAR_BIT; |
| 168 | } |
| 169 | else |
| 170 | { |
| 171 | cur_byte = (start + len) / FLOATFORMAT_CHAR_BIT; |
| 172 | cur_bitshift = |
| 173 | ((start + len) % FLOATFORMAT_CHAR_BIT) - FLOATFORMAT_CHAR_BIT; |
| 174 | } |
| 175 | if (cur_bitshift > -FLOATFORMAT_CHAR_BIT) |
| 176 | result = *(data + cur_byte) >> (-cur_bitshift); |
| 177 | else |
| 178 | result = 0; |
| 179 | cur_bitshift += FLOATFORMAT_CHAR_BIT; |
| 180 | if (order == floatformat_little) |
| 181 | ++cur_byte; |
| 182 | else |
| 183 | --cur_byte; |
| 184 | |
| 185 | /* Move towards the most significant part of the field. */ |
| 186 | while (cur_bitshift < len) |
| 187 | { |
| 188 | result |= (unsigned long)*(data + cur_byte) << cur_bitshift; |
| 189 | cur_bitshift += FLOATFORMAT_CHAR_BIT; |
| 190 | switch (order) |
| 191 | { |
| 192 | case floatformat_little: |
| 193 | ++cur_byte; |
| 194 | break; |
| 195 | case floatformat_big: |
| 196 | --cur_byte; |
| 197 | break; |
| 198 | } |
| 199 | } |
| 200 | if (len < sizeof(result) * FLOATFORMAT_CHAR_BIT) |
| 201 | /* Mask out bits which are not part of the field. */ |
| 202 | result &= ((1UL << len) - 1); |
| 203 | return result; |
| 204 | } |
| 205 | |
| 206 | /* Set a field which starts at START and is LEN bytes long. DATA and |
| 207 | TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */ |
| 208 | static void |
| 209 | put_field (unsigned char *data, enum floatformat_byteorders order, |
| 210 | unsigned int total_len, unsigned int start, unsigned int len, |
| 211 | unsigned long stuff_to_put) |
| 212 | { |
| 213 | unsigned int cur_byte; |
| 214 | int cur_bitshift; |
| 215 | |
| 216 | /* Caller must byte-swap words before calling this routine. */ |
| 217 | gdb_assert (order == floatformat_little || order == floatformat_big); |
| 218 | |
| 219 | /* Start at the least significant part of the field. */ |
| 220 | if (order == floatformat_little) |
| 221 | { |
| 222 | int excess = FLOATFORMAT_CHAR_BIT - (total_len % FLOATFORMAT_CHAR_BIT); |
| 223 | |
| 224 | cur_byte = (total_len / FLOATFORMAT_CHAR_BIT) |
| 225 | - ((start + len + excess) / FLOATFORMAT_CHAR_BIT); |
| 226 | cur_bitshift = ((start + len + excess) % FLOATFORMAT_CHAR_BIT) |
| 227 | - FLOATFORMAT_CHAR_BIT; |
| 228 | } |
| 229 | else |
| 230 | { |
| 231 | cur_byte = (start + len) / FLOATFORMAT_CHAR_BIT; |
| 232 | cur_bitshift = |
| 233 | ((start + len) % FLOATFORMAT_CHAR_BIT) - FLOATFORMAT_CHAR_BIT; |
| 234 | } |
| 235 | if (cur_bitshift > -FLOATFORMAT_CHAR_BIT) |
| 236 | { |
| 237 | *(data + cur_byte) &= |
| 238 | ~(((1 << ((start + len) % FLOATFORMAT_CHAR_BIT)) - 1) |
| 239 | << (-cur_bitshift)); |
| 240 | *(data + cur_byte) |= |
| 241 | (stuff_to_put & ((1 << FLOATFORMAT_CHAR_BIT) - 1)) << (-cur_bitshift); |
| 242 | } |
| 243 | cur_bitshift += FLOATFORMAT_CHAR_BIT; |
| 244 | if (order == floatformat_little) |
| 245 | ++cur_byte; |
| 246 | else |
| 247 | --cur_byte; |
| 248 | |
| 249 | /* Move towards the most significant part of the field. */ |
| 250 | while (cur_bitshift < len) |
| 251 | { |
| 252 | if (len - cur_bitshift < FLOATFORMAT_CHAR_BIT) |
| 253 | { |
| 254 | /* This is the last byte. */ |
| 255 | *(data + cur_byte) &= |
| 256 | ~((1 << (len - cur_bitshift)) - 1); |
| 257 | *(data + cur_byte) |= (stuff_to_put >> cur_bitshift); |
| 258 | } |
| 259 | else |
| 260 | *(data + cur_byte) = ((stuff_to_put >> cur_bitshift) |
| 261 | & ((1 << FLOATFORMAT_CHAR_BIT) - 1)); |
| 262 | cur_bitshift += FLOATFORMAT_CHAR_BIT; |
| 263 | if (order == floatformat_little) |
| 264 | ++cur_byte; |
| 265 | else |
| 266 | --cur_byte; |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | /* Check if VAL (which is assumed to be a floating point number whose |
| 271 | format is described by FMT) is negative. */ |
| 272 | static int |
| 273 | floatformat_is_negative (const struct floatformat *fmt, |
| 274 | const bfd_byte *uval) |
| 275 | { |
| 276 | enum floatformat_byteorders order; |
| 277 | unsigned char newfrom[FLOATFORMAT_LARGEST_BYTES]; |
| 278 | |
| 279 | gdb_assert (fmt != NULL); |
| 280 | gdb_assert (fmt->totalsize |
| 281 | <= FLOATFORMAT_LARGEST_BYTES * FLOATFORMAT_CHAR_BIT); |
| 282 | |
| 283 | /* An IBM long double (a two element array of double) always takes the |
| 284 | sign of the first double. */ |
| 285 | if (fmt->split_half) |
| 286 | fmt = fmt->split_half; |
| 287 | |
| 288 | order = floatformat_normalize_byteorder (fmt, uval, newfrom); |
| 289 | |
| 290 | if (order != fmt->byteorder) |
| 291 | uval = newfrom; |
| 292 | |
| 293 | return get_field (uval, order, fmt->totalsize, fmt->sign_start, 1); |
| 294 | } |
| 295 | |
| 296 | /* Check if VAL is "not a number" (NaN) for FMT. */ |
| 297 | static enum float_kind |
| 298 | floatformat_classify (const struct floatformat *fmt, |
| 299 | const bfd_byte *uval) |
| 300 | { |
| 301 | long exponent; |
| 302 | unsigned long mant; |
| 303 | unsigned int mant_bits, mant_off; |
| 304 | int mant_bits_left; |
| 305 | enum floatformat_byteorders order; |
| 306 | unsigned char newfrom[FLOATFORMAT_LARGEST_BYTES]; |
| 307 | int mant_zero; |
| 308 | |
| 309 | gdb_assert (fmt != NULL); |
| 310 | gdb_assert (fmt->totalsize |
| 311 | <= FLOATFORMAT_LARGEST_BYTES * FLOATFORMAT_CHAR_BIT); |
| 312 | |
| 313 | /* An IBM long double (a two element array of double) can be classified |
| 314 | by looking at the first double. inf and nan are specified as |
| 315 | ignoring the second double. zero and subnormal will always have |
| 316 | the second double 0.0 if the long double is correctly rounded. */ |
| 317 | if (fmt->split_half) |
| 318 | fmt = fmt->split_half; |
| 319 | |
| 320 | order = floatformat_normalize_byteorder (fmt, uval, newfrom); |
| 321 | |
| 322 | if (order != fmt->byteorder) |
| 323 | uval = newfrom; |
| 324 | |
| 325 | exponent = get_field (uval, order, fmt->totalsize, fmt->exp_start, |
| 326 | fmt->exp_len); |
| 327 | |
| 328 | mant_bits_left = fmt->man_len; |
| 329 | mant_off = fmt->man_start; |
| 330 | |
| 331 | mant_zero = 1; |
| 332 | while (mant_bits_left > 0) |
| 333 | { |
| 334 | mant_bits = std::min (mant_bits_left, 32); |
| 335 | |
| 336 | mant = get_field (uval, order, fmt->totalsize, mant_off, mant_bits); |
| 337 | |
| 338 | /* If there is an explicit integer bit, mask it off. */ |
| 339 | if (mant_off == fmt->man_start |
| 340 | && fmt->intbit == floatformat_intbit_yes) |
| 341 | mant &= ~(1 << (mant_bits - 1)); |
| 342 | |
| 343 | if (mant) |
| 344 | { |
| 345 | mant_zero = 0; |
| 346 | break; |
| 347 | } |
| 348 | |
| 349 | mant_off += mant_bits; |
| 350 | mant_bits_left -= mant_bits; |
| 351 | } |
| 352 | |
| 353 | /* If exp_nan is not set, assume that inf, NaN, and subnormals are not |
| 354 | supported. */ |
| 355 | if (! fmt->exp_nan) |
| 356 | { |
| 357 | if (mant_zero) |
| 358 | return float_zero; |
| 359 | else |
| 360 | return float_normal; |
| 361 | } |
| 362 | |
| 363 | if (exponent == 0) |
| 364 | { |
| 365 | if (mant_zero) |
| 366 | return float_zero; |
| 367 | else |
| 368 | return float_subnormal; |
| 369 | } |
| 370 | |
| 371 | if (exponent == fmt->exp_nan) |
| 372 | { |
| 373 | if (mant_zero) |
| 374 | return float_infinite; |
| 375 | else |
| 376 | return float_nan; |
| 377 | } |
| 378 | |
| 379 | return float_normal; |
| 380 | } |
| 381 | |
| 382 | /* Convert the mantissa of VAL (which is assumed to be a floating |
| 383 | point number whose format is described by FMT) into a hexadecimal |
| 384 | and store it in a static string. Return a pointer to that string. */ |
| 385 | static const char * |
| 386 | floatformat_mantissa (const struct floatformat *fmt, |
| 387 | const bfd_byte *val) |
| 388 | { |
| 389 | unsigned char *uval = (unsigned char *) val; |
| 390 | unsigned long mant; |
| 391 | unsigned int mant_bits, mant_off; |
| 392 | int mant_bits_left; |
| 393 | static char res[50]; |
| 394 | char buf[9]; |
| 395 | int len; |
| 396 | enum floatformat_byteorders order; |
| 397 | unsigned char newfrom[FLOATFORMAT_LARGEST_BYTES]; |
| 398 | |
| 399 | gdb_assert (fmt != NULL); |
| 400 | gdb_assert (fmt->totalsize |
| 401 | <= FLOATFORMAT_LARGEST_BYTES * FLOATFORMAT_CHAR_BIT); |
| 402 | |
| 403 | /* For IBM long double (a two element array of double), return the |
| 404 | mantissa of the first double. The problem with returning the |
| 405 | actual mantissa from both doubles is that there can be an |
| 406 | arbitrary number of implied 0's or 1's between the mantissas |
| 407 | of the first and second double. In any case, this function |
| 408 | is only used for dumping out nans, and a nan is specified to |
| 409 | ignore the value in the second double. */ |
| 410 | if (fmt->split_half) |
| 411 | fmt = fmt->split_half; |
| 412 | |
| 413 | order = floatformat_normalize_byteorder (fmt, uval, newfrom); |
| 414 | |
| 415 | if (order != fmt->byteorder) |
| 416 | uval = newfrom; |
| 417 | |
| 418 | if (! fmt->exp_nan) |
| 419 | return 0; |
| 420 | |
| 421 | /* Make sure we have enough room to store the mantissa. */ |
| 422 | gdb_assert (sizeof res > ((fmt->man_len + 7) / 8) * 2); |
| 423 | |
| 424 | mant_off = fmt->man_start; |
| 425 | mant_bits_left = fmt->man_len; |
| 426 | mant_bits = (mant_bits_left % 32) > 0 ? mant_bits_left % 32 : 32; |
| 427 | |
| 428 | mant = get_field (uval, order, fmt->totalsize, mant_off, mant_bits); |
| 429 | |
| 430 | len = xsnprintf (res, sizeof res, "%lx", mant); |
| 431 | |
| 432 | mant_off += mant_bits; |
| 433 | mant_bits_left -= mant_bits; |
| 434 | |
| 435 | while (mant_bits_left > 0) |
| 436 | { |
| 437 | mant = get_field (uval, order, fmt->totalsize, mant_off, 32); |
| 438 | |
| 439 | xsnprintf (buf, sizeof buf, "%08lx", mant); |
| 440 | gdb_assert (len + strlen (buf) <= sizeof res); |
| 441 | strcat (res, buf); |
| 442 | |
| 443 | mant_off += 32; |
| 444 | mant_bits_left -= 32; |
| 445 | } |
| 446 | |
| 447 | return res; |
| 448 | } |
| 449 | |
| 450 | /* Convert TO/FROM target to the hosts DOUBLEST floating-point format. |
| 451 | |
| 452 | If the host and target formats agree, we just copy the raw data |
| 453 | into the appropriate type of variable and return, letting the host |
| 454 | increase precision as necessary. Otherwise, we call the conversion |
| 455 | routine and let it do the dirty work. Note that even if the target |
| 456 | and host floating-point formats match, the length of the types |
| 457 | might still be different, so the conversion routines must make sure |
| 458 | to not overrun any buffers. For example, on x86, long double is |
| 459 | the 80-bit extended precision type on both 32-bit and 64-bit ABIs, |
| 460 | but by default it is stored as 12 bytes on 32-bit, and 16 bytes on |
| 461 | 64-bit, for alignment reasons. See comment in store_typed_floating |
| 462 | for a discussion about zeroing out remaining bytes in the target |
| 463 | buffer. */ |
| 464 | |
| 465 | static const struct floatformat *host_float_format = GDB_HOST_FLOAT_FORMAT; |
| 466 | static const struct floatformat *host_double_format = GDB_HOST_DOUBLE_FORMAT; |
| 467 | static const struct floatformat *host_long_double_format |
| 468 | = GDB_HOST_LONG_DOUBLE_FORMAT; |
| 469 | |
| 470 | /* Convert from FMT to a DOUBLEST. FROM is the address of the extended float. |
| 471 | Store the DOUBLEST in *TO. */ |
| 472 | static void |
| 473 | floatformat_to_doublest (const struct floatformat *fmt, |
| 474 | const void *from, DOUBLEST *to) |
| 475 | { |
| 476 | gdb_assert (fmt != NULL); |
| 477 | |
| 478 | if (fmt == host_float_format) |
| 479 | { |
| 480 | float val = 0; |
| 481 | |
| 482 | memcpy (&val, from, floatformat_totalsize_bytes (fmt)); |
| 483 | *to = val; |
| 484 | return; |
| 485 | } |
| 486 | else if (fmt == host_double_format) |
| 487 | { |
| 488 | double val = 0; |
| 489 | |
| 490 | memcpy (&val, from, floatformat_totalsize_bytes (fmt)); |
| 491 | *to = val; |
| 492 | return; |
| 493 | } |
| 494 | else if (fmt == host_long_double_format) |
| 495 | { |
| 496 | long double val = 0; |
| 497 | |
| 498 | memcpy (&val, from, floatformat_totalsize_bytes (fmt)); |
| 499 | *to = val; |
| 500 | return; |
| 501 | } |
| 502 | |
| 503 | unsigned char *ufrom = (unsigned char *) from; |
| 504 | DOUBLEST dto; |
| 505 | long exponent; |
| 506 | unsigned long mant; |
| 507 | unsigned int mant_bits, mant_off; |
| 508 | int mant_bits_left; |
| 509 | int special_exponent; /* It's a NaN, denorm or zero. */ |
| 510 | enum floatformat_byteorders order; |
| 511 | unsigned char newfrom[FLOATFORMAT_LARGEST_BYTES]; |
| 512 | enum float_kind kind; |
| 513 | |
| 514 | gdb_assert (fmt->totalsize |
| 515 | <= FLOATFORMAT_LARGEST_BYTES * FLOATFORMAT_CHAR_BIT); |
| 516 | |
| 517 | /* For non-numbers, reuse libiberty's logic to find the correct |
| 518 | format. We do not lose any precision in this case by passing |
| 519 | through a double. */ |
| 520 | kind = floatformat_classify (fmt, (const bfd_byte *) from); |
| 521 | if (kind == float_infinite || kind == float_nan) |
| 522 | { |
| 523 | double dto; |
| 524 | |
| 525 | floatformat_to_double (fmt->split_half ? fmt->split_half : fmt, |
| 526 | from, &dto); |
| 527 | *to = (DOUBLEST) dto; |
| 528 | return; |
| 529 | } |
| 530 | |
| 531 | order = floatformat_normalize_byteorder (fmt, ufrom, newfrom); |
| 532 | |
| 533 | if (order != fmt->byteorder) |
| 534 | ufrom = newfrom; |
| 535 | |
| 536 | if (fmt->split_half) |
| 537 | { |
| 538 | DOUBLEST dtop, dbot; |
| 539 | |
| 540 | floatformat_to_doublest (fmt->split_half, ufrom, &dtop); |
| 541 | /* Preserve the sign of 0, which is the sign of the top |
| 542 | half. */ |
| 543 | if (dtop == 0.0) |
| 544 | { |
| 545 | *to = dtop; |
| 546 | return; |
| 547 | } |
| 548 | floatformat_to_doublest (fmt->split_half, |
| 549 | ufrom + fmt->totalsize / FLOATFORMAT_CHAR_BIT / 2, |
| 550 | &dbot); |
| 551 | *to = dtop + dbot; |
| 552 | return; |
| 553 | } |
| 554 | |
| 555 | exponent = get_field (ufrom, order, fmt->totalsize, fmt->exp_start, |
| 556 | fmt->exp_len); |
| 557 | /* Note that if exponent indicates a NaN, we can't really do anything useful |
| 558 | (not knowing if the host has NaN's, or how to build one). So it will |
| 559 | end up as an infinity or something close; that is OK. */ |
| 560 | |
| 561 | mant_bits_left = fmt->man_len; |
| 562 | mant_off = fmt->man_start; |
| 563 | dto = 0.0; |
| 564 | |
| 565 | special_exponent = exponent == 0 || exponent == fmt->exp_nan; |
| 566 | |
| 567 | /* Don't bias NaNs. Use minimum exponent for denorms. For |
| 568 | simplicity, we don't check for zero as the exponent doesn't matter. |
| 569 | Note the cast to int; exp_bias is unsigned, so it's important to |
| 570 | make sure the operation is done in signed arithmetic. */ |
| 571 | if (!special_exponent) |
| 572 | exponent -= fmt->exp_bias; |
| 573 | else if (exponent == 0) |
| 574 | exponent = 1 - fmt->exp_bias; |
| 575 | |
| 576 | /* Build the result algebraically. Might go infinite, underflow, etc; |
| 577 | who cares. */ |
| 578 | |
| 579 | /* If this format uses a hidden bit, explicitly add it in now. Otherwise, |
| 580 | increment the exponent by one to account for the integer bit. */ |
| 581 | |
| 582 | if (!special_exponent) |
| 583 | { |
| 584 | if (fmt->intbit == floatformat_intbit_no) |
| 585 | dto = ldexp (1.0, exponent); |
| 586 | else |
| 587 | exponent++; |
| 588 | } |
| 589 | |
| 590 | while (mant_bits_left > 0) |
| 591 | { |
| 592 | mant_bits = std::min (mant_bits_left, 32); |
| 593 | |
| 594 | mant = get_field (ufrom, order, fmt->totalsize, mant_off, mant_bits); |
| 595 | |
| 596 | dto += ldexp ((double) mant, exponent - mant_bits); |
| 597 | exponent -= mant_bits; |
| 598 | mant_off += mant_bits; |
| 599 | mant_bits_left -= mant_bits; |
| 600 | } |
| 601 | |
| 602 | /* Negate it if negative. */ |
| 603 | if (get_field (ufrom, order, fmt->totalsize, fmt->sign_start, 1)) |
| 604 | dto = -dto; |
| 605 | *to = dto; |
| 606 | } |
| 607 | |
| 608 | /* Convert the DOUBLEST *FROM to an extended float in format FMT and |
| 609 | store where TO points. */ |
| 610 | static void |
| 611 | floatformat_from_doublest (const struct floatformat *fmt, |
| 612 | const DOUBLEST *from, void *to) |
| 613 | { |
| 614 | gdb_assert (fmt != NULL); |
| 615 | |
| 616 | if (fmt == host_float_format) |
| 617 | { |
| 618 | float val = *from; |
| 619 | |
| 620 | memcpy (to, &val, floatformat_totalsize_bytes (fmt)); |
| 621 | return; |
| 622 | } |
| 623 | else if (fmt == host_double_format) |
| 624 | { |
| 625 | double val = *from; |
| 626 | |
| 627 | memcpy (to, &val, floatformat_totalsize_bytes (fmt)); |
| 628 | return; |
| 629 | } |
| 630 | else if (fmt == host_long_double_format) |
| 631 | { |
| 632 | long double val = *from; |
| 633 | |
| 634 | memcpy (to, &val, floatformat_totalsize_bytes (fmt)); |
| 635 | return; |
| 636 | } |
| 637 | |
| 638 | DOUBLEST dfrom; |
| 639 | int exponent; |
| 640 | DOUBLEST mant; |
| 641 | unsigned int mant_bits, mant_off; |
| 642 | int mant_bits_left; |
| 643 | unsigned char *uto = (unsigned char *) to; |
| 644 | enum floatformat_byteorders order = fmt->byteorder; |
| 645 | unsigned char newto[FLOATFORMAT_LARGEST_BYTES]; |
| 646 | |
| 647 | if (order != floatformat_little) |
| 648 | order = floatformat_big; |
| 649 | |
| 650 | if (order != fmt->byteorder) |
| 651 | uto = newto; |
| 652 | |
| 653 | memcpy (&dfrom, from, sizeof (dfrom)); |
| 654 | memset (uto, 0, floatformat_totalsize_bytes (fmt)); |
| 655 | |
| 656 | if (fmt->split_half) |
| 657 | { |
| 658 | /* Use static volatile to ensure that any excess precision is |
| 659 | removed via storing in memory, and so the top half really is |
| 660 | the result of converting to double. */ |
| 661 | static volatile double dtop, dbot; |
| 662 | DOUBLEST dtopnv, dbotnv; |
| 663 | |
| 664 | dtop = (double) dfrom; |
| 665 | /* If the rounded top half is Inf, the bottom must be 0 not NaN |
| 666 | or Inf. */ |
| 667 | if (dtop + dtop == dtop && dtop != 0.0) |
| 668 | dbot = 0.0; |
| 669 | else |
| 670 | dbot = (double) (dfrom - (DOUBLEST) dtop); |
| 671 | dtopnv = dtop; |
| 672 | dbotnv = dbot; |
| 673 | floatformat_from_doublest (fmt->split_half, &dtopnv, uto); |
| 674 | floatformat_from_doublest (fmt->split_half, &dbotnv, |
| 675 | (uto |
| 676 | + fmt->totalsize / FLOATFORMAT_CHAR_BIT / 2)); |
| 677 | return; |
| 678 | } |
| 679 | |
| 680 | if (dfrom == 0) |
| 681 | goto finalize_byteorder; /* Result is zero */ |
| 682 | if (dfrom != dfrom) /* Result is NaN */ |
| 683 | { |
| 684 | /* From is NaN */ |
| 685 | put_field (uto, order, fmt->totalsize, fmt->exp_start, |
| 686 | fmt->exp_len, fmt->exp_nan); |
| 687 | /* Be sure it's not infinity, but NaN value is irrel. */ |
| 688 | put_field (uto, order, fmt->totalsize, fmt->man_start, |
| 689 | fmt->man_len, 1); |
| 690 | goto finalize_byteorder; |
| 691 | } |
| 692 | |
| 693 | /* If negative, set the sign bit. */ |
| 694 | if (dfrom < 0) |
| 695 | { |
| 696 | put_field (uto, order, fmt->totalsize, fmt->sign_start, 1, 1); |
| 697 | dfrom = -dfrom; |
| 698 | } |
| 699 | |
| 700 | if (dfrom + dfrom == dfrom && dfrom != 0.0) /* Result is Infinity. */ |
| 701 | { |
| 702 | /* Infinity exponent is same as NaN's. */ |
| 703 | put_field (uto, order, fmt->totalsize, fmt->exp_start, |
| 704 | fmt->exp_len, fmt->exp_nan); |
| 705 | /* Infinity mantissa is all zeroes. */ |
| 706 | put_field (uto, order, fmt->totalsize, fmt->man_start, |
| 707 | fmt->man_len, 0); |
| 708 | goto finalize_byteorder; |
| 709 | } |
| 710 | |
| 711 | #ifdef HAVE_LONG_DOUBLE |
| 712 | mant = frexpl (dfrom, &exponent); |
| 713 | #else |
| 714 | mant = frexp (dfrom, &exponent); |
| 715 | #endif |
| 716 | |
| 717 | if (exponent + fmt->exp_bias <= 0) |
| 718 | { |
| 719 | /* The value is too small to be expressed in the destination |
| 720 | type (not enough bits in the exponent. Treat as 0. */ |
| 721 | put_field (uto, order, fmt->totalsize, fmt->exp_start, |
| 722 | fmt->exp_len, 0); |
| 723 | put_field (uto, order, fmt->totalsize, fmt->man_start, |
| 724 | fmt->man_len, 0); |
| 725 | goto finalize_byteorder; |
| 726 | } |
| 727 | |
| 728 | if (exponent + fmt->exp_bias >= (1 << fmt->exp_len)) |
| 729 | { |
| 730 | /* The value is too large to fit into the destination. |
| 731 | Treat as infinity. */ |
| 732 | put_field (uto, order, fmt->totalsize, fmt->exp_start, |
| 733 | fmt->exp_len, fmt->exp_nan); |
| 734 | put_field (uto, order, fmt->totalsize, fmt->man_start, |
| 735 | fmt->man_len, 0); |
| 736 | goto finalize_byteorder; |
| 737 | } |
| 738 | |
| 739 | put_field (uto, order, fmt->totalsize, fmt->exp_start, fmt->exp_len, |
| 740 | exponent + fmt->exp_bias - 1); |
| 741 | |
| 742 | mant_bits_left = fmt->man_len; |
| 743 | mant_off = fmt->man_start; |
| 744 | while (mant_bits_left > 0) |
| 745 | { |
| 746 | unsigned long mant_long; |
| 747 | |
| 748 | mant_bits = mant_bits_left < 32 ? mant_bits_left : 32; |
| 749 | |
| 750 | mant *= 4294967296.0; |
| 751 | mant_long = ((unsigned long) mant) & 0xffffffffL; |
| 752 | mant -= mant_long; |
| 753 | |
| 754 | /* If the integer bit is implicit, then we need to discard it. |
| 755 | If we are discarding a zero, we should be (but are not) creating |
| 756 | a denormalized number which means adjusting the exponent |
| 757 | (I think). */ |
| 758 | if (mant_bits_left == fmt->man_len |
| 759 | && fmt->intbit == floatformat_intbit_no) |
| 760 | { |
| 761 | mant_long <<= 1; |
| 762 | mant_long &= 0xffffffffL; |
| 763 | /* If we are processing the top 32 mantissa bits of a doublest |
| 764 | so as to convert to a float value with implied integer bit, |
| 765 | we will only be putting 31 of those 32 bits into the |
| 766 | final value due to the discarding of the top bit. In the |
| 767 | case of a small float value where the number of mantissa |
| 768 | bits is less than 32, discarding the top bit does not alter |
| 769 | the number of bits we will be adding to the result. */ |
| 770 | if (mant_bits == 32) |
| 771 | mant_bits -= 1; |
| 772 | } |
| 773 | |
| 774 | if (mant_bits < 32) |
| 775 | { |
| 776 | /* The bits we want are in the most significant MANT_BITS bits of |
| 777 | mant_long. Move them to the least significant. */ |
| 778 | mant_long >>= 32 - mant_bits; |
| 779 | } |
| 780 | |
| 781 | put_field (uto, order, fmt->totalsize, |
| 782 | mant_off, mant_bits, mant_long); |
| 783 | mant_off += mant_bits; |
| 784 | mant_bits_left -= mant_bits; |
| 785 | } |
| 786 | |
| 787 | finalize_byteorder: |
| 788 | /* Do we need to byte-swap the words in the result? */ |
| 789 | if (order != fmt->byteorder) |
| 790 | floatformat_normalize_byteorder (fmt, newto, to); |
| 791 | } |
| 792 | |
| 793 | /* Convert the byte-stream ADDR, interpreted as floating-point format FMT, |
| 794 | to a string, optionally using the print format FORMAT. */ |
| 795 | static std::string |
| 796 | floatformat_to_string (const struct floatformat *fmt, |
| 797 | const gdb_byte *in, const char *format) |
| 798 | { |
| 799 | /* Unless we need to adhere to a specific format, provide special |
| 800 | output for certain cases. */ |
| 801 | if (format == nullptr) |
| 802 | { |
| 803 | /* Detect invalid representations. */ |
| 804 | if (!floatformat_is_valid (fmt, in)) |
| 805 | return "<invalid float value>"; |
| 806 | |
| 807 | /* Handle NaN and Inf. */ |
| 808 | enum float_kind kind = floatformat_classify (fmt, in); |
| 809 | if (kind == float_nan) |
| 810 | { |
| 811 | const char *sign = floatformat_is_negative (fmt, in)? "-" : ""; |
| 812 | const char *mantissa = floatformat_mantissa (fmt, in); |
| 813 | return string_printf ("%snan(0x%s)", sign, mantissa); |
| 814 | } |
| 815 | else if (kind == float_infinite) |
| 816 | { |
| 817 | const char *sign = floatformat_is_negative (fmt, in)? "-" : ""; |
| 818 | return string_printf ("%sinf", sign); |
| 819 | } |
| 820 | } |
| 821 | |
| 822 | /* Determine the format string to use on the host side. */ |
| 823 | std::string host_format; |
| 824 | char conversion; |
| 825 | |
| 826 | if (format == nullptr) |
| 827 | { |
| 828 | /* If no format was specified, print the number using a format string |
| 829 | where the precision is set to the DECIMAL_DIG value for the given |
| 830 | floating-point format. This value is computed as |
| 831 | |
| 832 | ceil(1 + p * log10(b)), |
| 833 | |
| 834 | where p is the precision of the floating-point format in bits, and |
| 835 | b is the base (which is always 2 for the formats we support). */ |
| 836 | const double log10_2 = .30102999566398119521; |
| 837 | double d_decimal_dig = 1 + floatformat_precision (fmt) * log10_2; |
| 838 | int decimal_dig = d_decimal_dig; |
| 839 | if (decimal_dig < d_decimal_dig) |
| 840 | decimal_dig++; |
| 841 | |
| 842 | host_format = string_printf ("%%.%d", decimal_dig); |
| 843 | conversion = 'g'; |
| 844 | } |
| 845 | else |
| 846 | { |
| 847 | /* Use the specified format, stripping out the conversion character |
| 848 | and length modifier, if present. */ |
| 849 | size_t len = strlen (format); |
| 850 | gdb_assert (len > 1); |
| 851 | conversion = format[--len]; |
| 852 | gdb_assert (conversion == 'e' || conversion == 'f' || conversion == 'g' |
| 853 | || conversion == 'E' || conversion == 'G'); |
| 854 | if (format[len - 1] == 'L') |
| 855 | len--; |
| 856 | |
| 857 | host_format = std::string (format, len); |
| 858 | } |
| 859 | |
| 860 | /* Add the length modifier and conversion character appropriate for |
| 861 | handling the host DOUBLEST type. */ |
| 862 | #ifdef HAVE_LONG_DOUBLE |
| 863 | host_format += 'L'; |
| 864 | #endif |
| 865 | host_format += conversion; |
| 866 | |
| 867 | DOUBLEST doub; |
| 868 | floatformat_to_doublest (fmt, in, &doub); |
| 869 | return string_printf (host_format.c_str (), doub); |
| 870 | } |
| 871 | |
| 872 | /* Parse string STRING into a target floating-number of format FMT and |
| 873 | store it as byte-stream ADDR. Return whether parsing succeeded. */ |
| 874 | static bool |
| 875 | floatformat_from_string (const struct floatformat *fmt, gdb_byte *out, |
| 876 | const std::string &in) |
| 877 | { |
| 878 | DOUBLEST doub; |
| 879 | int n, num; |
| 880 | #ifdef HAVE_LONG_DOUBLE |
| 881 | const char *scan_format = "%Lg%n"; |
| 882 | #else |
| 883 | const char *scan_format = "%lg%n"; |
| 884 | #endif |
| 885 | num = sscanf (in.c_str (), scan_format, &doub, &n); |
| 886 | |
| 887 | /* The sscanf man page suggests not making any assumptions on the effect |
| 888 | of %n on the result, so we don't. |
| 889 | That is why we simply test num == 0. */ |
| 890 | if (num == 0) |
| 891 | return false; |
| 892 | |
| 893 | /* We only accept the whole string. */ |
| 894 | if (in[n]) |
| 895 | return false; |
| 896 | |
| 897 | floatformat_from_doublest (fmt, &doub, out); |
| 898 | return true; |
| 899 | } |
| 900 | |
| 901 | /* Convert the byte-stream ADDR, interpreted as floating-point format FMT, |
| 902 | to an integer value (rounding towards zero). */ |
| 903 | static LONGEST |
| 904 | floatformat_to_longest (const struct floatformat *fmt, const gdb_byte *addr) |
| 905 | { |
| 906 | DOUBLEST d; |
| 907 | floatformat_to_doublest (fmt, addr, &d); |
| 908 | return (LONGEST) d; |
| 909 | } |
| 910 | |
| 911 | /* Convert signed integer VAL to a target floating-number of format FMT |
| 912 | and store it as byte-stream ADDR. */ |
| 913 | static void |
| 914 | floatformat_from_longest (const struct floatformat *fmt, gdb_byte *addr, |
| 915 | LONGEST val) |
| 916 | { |
| 917 | DOUBLEST d = (DOUBLEST) val; |
| 918 | floatformat_from_doublest (fmt, &d, addr); |
| 919 | } |
| 920 | |
| 921 | /* Convert unsigned integer VAL to a target floating-number of format FMT |
| 922 | and store it as byte-stream ADDR. */ |
| 923 | static void |
| 924 | floatformat_from_ulongest (const struct floatformat *fmt, gdb_byte *addr, |
| 925 | ULONGEST val) |
| 926 | { |
| 927 | DOUBLEST d = (DOUBLEST) val; |
| 928 | floatformat_from_doublest (fmt, &d, addr); |
| 929 | } |
| 930 | |
| 931 | /* Convert the byte-stream ADDR, interpreted as floating-point format FMT, |
| 932 | to a floating-point value in the host "double" format. */ |
| 933 | static double |
| 934 | floatformat_to_host_double (const struct floatformat *fmt, |
| 935 | const gdb_byte *addr) |
| 936 | { |
| 937 | DOUBLEST d; |
| 938 | floatformat_to_doublest (fmt, addr, &d); |
| 939 | return (double) d; |
| 940 | } |
| 941 | |
| 942 | /* Convert floating-point value VAL in the host "double" format to a target |
| 943 | floating-number of format FMT and store it as byte-stream ADDR. */ |
| 944 | static void |
| 945 | floatformat_from_host_double (const struct floatformat *fmt, gdb_byte *addr, |
| 946 | double val) |
| 947 | { |
| 948 | DOUBLEST d = (DOUBLEST) val; |
| 949 | floatformat_from_doublest (fmt, &d, addr); |
| 950 | } |
| 951 | |
| 952 | /* Convert a floating-point number of format FROM_FMT from the target |
| 953 | byte-stream FROM to a floating-point number of format TO_FMT, and |
| 954 | store it to the target byte-stream TO. */ |
| 955 | static void |
| 956 | floatformat_convert (const gdb_byte *from, const struct floatformat *from_fmt, |
| 957 | gdb_byte *to, const struct floatformat *to_fmt) |
| 958 | { |
| 959 | if (from_fmt == to_fmt) |
| 960 | { |
| 961 | /* The floating-point formats match, so we simply copy the data. */ |
| 962 | memcpy (to, from, floatformat_totalsize_bytes (to_fmt)); |
| 963 | } |
| 964 | else |
| 965 | { |
| 966 | /* The floating-point formats don't match. The best we can do |
| 967 | (apart from simulating the target FPU) is converting to the |
| 968 | widest floating-point type supported by the host, and then |
| 969 | again to the desired type. */ |
| 970 | DOUBLEST d; |
| 971 | |
| 972 | floatformat_to_doublest (from_fmt, from, &d); |
| 973 | floatformat_from_doublest (to_fmt, &d, to); |
| 974 | } |
| 975 | } |
| 976 | |
| 977 | /* Perform the binary operation indicated by OPCODE, using as operands the |
| 978 | target byte streams X and Y, interpreted as floating-point numbers of |
| 979 | formats FMT_X and FMT_Y, respectively. Convert the result to format |
| 980 | FMT_RES and store it into the byte-stream RES. */ |
| 981 | static void |
| 982 | floatformat_binop (enum exp_opcode op, |
| 983 | const struct floatformat *fmt_x, const gdb_byte *x, |
| 984 | const struct floatformat *fmt_y, const gdb_byte *y, |
| 985 | const struct floatformat *fmt_result, gdb_byte *result) |
| 986 | { |
| 987 | DOUBLEST v1, v2, v = 0; |
| 988 | |
| 989 | floatformat_to_doublest (fmt_x, x, &v1); |
| 990 | floatformat_to_doublest (fmt_y, y, &v2); |
| 991 | |
| 992 | switch (op) |
| 993 | { |
| 994 | case BINOP_ADD: |
| 995 | v = v1 + v2; |
| 996 | break; |
| 997 | |
| 998 | case BINOP_SUB: |
| 999 | v = v1 - v2; |
| 1000 | break; |
| 1001 | |
| 1002 | case BINOP_MUL: |
| 1003 | v = v1 * v2; |
| 1004 | break; |
| 1005 | |
| 1006 | case BINOP_DIV: |
| 1007 | v = v1 / v2; |
| 1008 | break; |
| 1009 | |
| 1010 | case BINOP_EXP: |
| 1011 | errno = 0; |
| 1012 | v = pow (v1, v2); |
| 1013 | if (errno) |
| 1014 | error (_("Cannot perform exponentiation: %s"), |
| 1015 | safe_strerror (errno)); |
| 1016 | break; |
| 1017 | |
| 1018 | case BINOP_MIN: |
| 1019 | v = v1 < v2 ? v1 : v2; |
| 1020 | break; |
| 1021 | |
| 1022 | case BINOP_MAX: |
| 1023 | v = v1 > v2 ? v1 : v2; |
| 1024 | break; |
| 1025 | |
| 1026 | default: |
| 1027 | error (_("Integer-only operation on floating point number.")); |
| 1028 | break; |
| 1029 | } |
| 1030 | |
| 1031 | floatformat_from_doublest (fmt_result, &v, result); |
| 1032 | } |
| 1033 | |
| 1034 | /* Compare the two target byte streams X and Y, interpreted as floating-point |
| 1035 | numbers of formats FMT_X and FMT_Y, respectively. Return zero if X and Y |
| 1036 | are equal, -1 if X is less than Y, and 1 otherwise. */ |
| 1037 | static int |
| 1038 | floatformat_compare (const struct floatformat *fmt_x, const gdb_byte *x, |
| 1039 | const struct floatformat *fmt_y, const gdb_byte *y) |
| 1040 | { |
| 1041 | DOUBLEST v1, v2; |
| 1042 | |
| 1043 | floatformat_to_doublest (fmt_x, x, &v1); |
| 1044 | floatformat_to_doublest (fmt_y, y, &v2); |
| 1045 | |
| 1046 | if (v1 == v2) |
| 1047 | return 0; |
| 1048 | if (v1 < v2) |
| 1049 | return -1; |
| 1050 | return 1; |
| 1051 | } |
| 1052 | |
| 1053 | |
| 1054 | /* Helper routines operating on decimal floating-point data. */ |
| 1055 | |
| 1056 | /* Decimal floating point is one of the extension to IEEE 754, which is |
| 1057 | described in http://grouper.ieee.org/groups/754/revision.html and |
| 1058 | http://www2.hursley.ibm.com/decimal/. It completes binary floating |
| 1059 | point by representing floating point more exactly. */ |
| 1060 | |
| 1061 | /* The order of the following headers is important for making sure |
| 1062 | decNumber structure is large enough to hold decimal128 digits. */ |
| 1063 | |
| 1064 | #include "dpd/decimal128.h" |
| 1065 | #include "dpd/decimal64.h" |
| 1066 | #include "dpd/decimal32.h" |
| 1067 | |
| 1068 | /* When using decimal128, this is the maximum string length + 1 |
| 1069 | (value comes from libdecnumber's DECIMAL128_String constant). */ |
| 1070 | #define MAX_DECIMAL_STRING 43 |
| 1071 | |
| 1072 | /* In GDB, we are using an array of gdb_byte to represent decimal values. |
| 1073 | They are stored in host byte order. This routine does the conversion if |
| 1074 | the target byte order is different. */ |
| 1075 | static void |
| 1076 | match_endianness (const gdb_byte *from, int len, enum bfd_endian byte_order, |
| 1077 | gdb_byte *to) |
| 1078 | { |
| 1079 | int i; |
| 1080 | |
| 1081 | #if WORDS_BIGENDIAN |
| 1082 | #define OPPOSITE_BYTE_ORDER BFD_ENDIAN_LITTLE |
| 1083 | #else |
| 1084 | #define OPPOSITE_BYTE_ORDER BFD_ENDIAN_BIG |
| 1085 | #endif |
| 1086 | |
| 1087 | if (byte_order == OPPOSITE_BYTE_ORDER) |
| 1088 | for (i = 0; i < len; i++) |
| 1089 | to[i] = from[len - i - 1]; |
| 1090 | else |
| 1091 | for (i = 0; i < len; i++) |
| 1092 | to[i] = from[i]; |
| 1093 | |
| 1094 | return; |
| 1095 | } |
| 1096 | |
| 1097 | /* Helper function to get the appropriate libdecnumber context for each size |
| 1098 | of decimal float. */ |
| 1099 | static void |
| 1100 | set_decnumber_context (decContext *ctx, int len) |
| 1101 | { |
| 1102 | switch (len) |
| 1103 | { |
| 1104 | case 4: |
| 1105 | decContextDefault (ctx, DEC_INIT_DECIMAL32); |
| 1106 | break; |
| 1107 | case 8: |
| 1108 | decContextDefault (ctx, DEC_INIT_DECIMAL64); |
| 1109 | break; |
| 1110 | case 16: |
| 1111 | decContextDefault (ctx, DEC_INIT_DECIMAL128); |
| 1112 | break; |
| 1113 | } |
| 1114 | |
| 1115 | ctx->traps = 0; |
| 1116 | } |
| 1117 | |
| 1118 | /* Check for errors signaled in the decimal context structure. */ |
| 1119 | static void |
| 1120 | decimal_check_errors (decContext *ctx) |
| 1121 | { |
| 1122 | /* An error here could be a division by zero, an overflow, an underflow or |
| 1123 | an invalid operation (from the DEC_Errors constant in decContext.h). |
| 1124 | Since GDB doesn't complain about division by zero, overflow or underflow |
| 1125 | errors for binary floating, we won't complain about them for decimal |
| 1126 | floating either. */ |
| 1127 | if (ctx->status & DEC_IEEE_854_Invalid_operation) |
| 1128 | { |
| 1129 | /* Leave only the error bits in the status flags. */ |
| 1130 | ctx->status &= DEC_IEEE_854_Invalid_operation; |
| 1131 | error (_("Cannot perform operation: %s"), |
| 1132 | decContextStatusToString (ctx)); |
| 1133 | } |
| 1134 | } |
| 1135 | |
| 1136 | /* Helper function to convert from libdecnumber's appropriate representation |
| 1137 | for computation to each size of decimal float. */ |
| 1138 | static void |
| 1139 | decimal_from_number (const decNumber *from, gdb_byte *to, int len) |
| 1140 | { |
| 1141 | decContext set; |
| 1142 | |
| 1143 | set_decnumber_context (&set, len); |
| 1144 | |
| 1145 | switch (len) |
| 1146 | { |
| 1147 | case 4: |
| 1148 | decimal32FromNumber ((decimal32 *) to, from, &set); |
| 1149 | break; |
| 1150 | case 8: |
| 1151 | decimal64FromNumber ((decimal64 *) to, from, &set); |
| 1152 | break; |
| 1153 | case 16: |
| 1154 | decimal128FromNumber ((decimal128 *) to, from, &set); |
| 1155 | break; |
| 1156 | } |
| 1157 | } |
| 1158 | |
| 1159 | /* Helper function to convert each size of decimal float to libdecnumber's |
| 1160 | appropriate representation for computation. */ |
| 1161 | static void |
| 1162 | decimal_to_number (const gdb_byte *from, int len, decNumber *to) |
| 1163 | { |
| 1164 | switch (len) |
| 1165 | { |
| 1166 | case 4: |
| 1167 | decimal32ToNumber ((decimal32 *) from, to); |
| 1168 | break; |
| 1169 | case 8: |
| 1170 | decimal64ToNumber ((decimal64 *) from, to); |
| 1171 | break; |
| 1172 | case 16: |
| 1173 | decimal128ToNumber ((decimal128 *) from, to); |
| 1174 | break; |
| 1175 | default: |
| 1176 | error (_("Unknown decimal floating point type.")); |
| 1177 | break; |
| 1178 | } |
| 1179 | } |
| 1180 | |
| 1181 | /* Convert decimal type to its string representation. LEN is the length |
| 1182 | of the decimal type, 4 bytes for decimal32, 8 bytes for decimal64 and |
| 1183 | 16 bytes for decimal128. */ |
| 1184 | static std::string |
| 1185 | decimal_to_string (const gdb_byte *decbytes, int len, |
| 1186 | enum bfd_endian byte_order, const char *format = nullptr) |
| 1187 | { |
| 1188 | gdb_byte dec[16]; |
| 1189 | |
| 1190 | match_endianness (decbytes, len, byte_order, dec); |
| 1191 | |
| 1192 | if (format != nullptr) |
| 1193 | { |
| 1194 | /* We don't handle format strings (yet). If the host printf supports |
| 1195 | decimal floating point types, just use this. Otherwise, fall back |
| 1196 | to printing the number while ignoring the format string. */ |
| 1197 | #if defined (PRINTF_HAS_DECFLOAT) |
| 1198 | /* FIXME: This makes unwarranted assumptions about the host ABI! */ |
| 1199 | return string_printf (format, dec); |
| 1200 | #endif |
| 1201 | } |
| 1202 | |
| 1203 | std::string result; |
| 1204 | result.resize (MAX_DECIMAL_STRING); |
| 1205 | |
| 1206 | switch (len) |
| 1207 | { |
| 1208 | case 4: |
| 1209 | decimal32ToString ((decimal32 *) dec, &result[0]); |
| 1210 | break; |
| 1211 | case 8: |
| 1212 | decimal64ToString ((decimal64 *) dec, &result[0]); |
| 1213 | break; |
| 1214 | case 16: |
| 1215 | decimal128ToString ((decimal128 *) dec, &result[0]); |
| 1216 | break; |
| 1217 | default: |
| 1218 | error (_("Unknown decimal floating point type.")); |
| 1219 | break; |
| 1220 | } |
| 1221 | |
| 1222 | return result; |
| 1223 | } |
| 1224 | |
| 1225 | /* Convert the string form of a decimal value to its decimal representation. |
| 1226 | LEN is the length of the decimal type, 4 bytes for decimal32, 8 bytes for |
| 1227 | decimal64 and 16 bytes for decimal128. */ |
| 1228 | static bool |
| 1229 | decimal_from_string (gdb_byte *decbytes, int len, enum bfd_endian byte_order, |
| 1230 | const std::string &string) |
| 1231 | { |
| 1232 | decContext set; |
| 1233 | gdb_byte dec[16]; |
| 1234 | |
| 1235 | set_decnumber_context (&set, len); |
| 1236 | |
| 1237 | switch (len) |
| 1238 | { |
| 1239 | case 4: |
| 1240 | decimal32FromString ((decimal32 *) dec, string.c_str (), &set); |
| 1241 | break; |
| 1242 | case 8: |
| 1243 | decimal64FromString ((decimal64 *) dec, string.c_str (), &set); |
| 1244 | break; |
| 1245 | case 16: |
| 1246 | decimal128FromString ((decimal128 *) dec, string.c_str (), &set); |
| 1247 | break; |
| 1248 | default: |
| 1249 | error (_("Unknown decimal floating point type.")); |
| 1250 | break; |
| 1251 | } |
| 1252 | |
| 1253 | match_endianness (dec, len, byte_order, decbytes); |
| 1254 | |
| 1255 | /* Check for errors in the DFP operation. */ |
| 1256 | decimal_check_errors (&set); |
| 1257 | |
| 1258 | return true; |
| 1259 | } |
| 1260 | |
| 1261 | /* Converts a LONGEST to a decimal float of specified LEN bytes. */ |
| 1262 | static void |
| 1263 | decimal_from_longest (LONGEST from, |
| 1264 | gdb_byte *to, int len, enum bfd_endian byte_order) |
| 1265 | { |
| 1266 | gdb_byte dec[16]; |
| 1267 | decNumber number; |
| 1268 | if ((int32_t) from != from) |
| 1269 | /* libdecnumber can convert only 32-bit integers. */ |
| 1270 | error (_("Conversion of large integer to a " |
| 1271 | "decimal floating type is not supported.")); |
| 1272 | |
| 1273 | decNumberFromInt32 (&number, (int32_t) from); |
| 1274 | |
| 1275 | decimal_from_number (&number, dec, len); |
| 1276 | match_endianness (dec, len, byte_order, to); |
| 1277 | } |
| 1278 | |
| 1279 | /* Converts a ULONGEST to a decimal float of specified LEN bytes. */ |
| 1280 | static void |
| 1281 | decimal_from_ulongest (ULONGEST from, |
| 1282 | gdb_byte *to, int len, enum bfd_endian byte_order) |
| 1283 | { |
| 1284 | gdb_byte dec[16]; |
| 1285 | decNumber number; |
| 1286 | |
| 1287 | if ((uint32_t) from != from) |
| 1288 | /* libdecnumber can convert only 32-bit integers. */ |
| 1289 | error (_("Conversion of large integer to a " |
| 1290 | "decimal floating type is not supported.")); |
| 1291 | |
| 1292 | decNumberFromUInt32 (&number, (uint32_t) from); |
| 1293 | |
| 1294 | decimal_from_number (&number, dec, len); |
| 1295 | match_endianness (dec, len, byte_order, to); |
| 1296 | } |
| 1297 | |
| 1298 | /* Converts a decimal float of LEN bytes to a LONGEST. */ |
| 1299 | static LONGEST |
| 1300 | decimal_to_longest (const gdb_byte *from, int len, enum bfd_endian byte_order) |
| 1301 | { |
| 1302 | /* libdecnumber has a function to convert from decimal to integer, but |
| 1303 | it doesn't work when the decimal number has a fractional part. */ |
| 1304 | std::string str = decimal_to_string (from, len, byte_order); |
| 1305 | return strtoll (str.c_str (), NULL, 10); |
| 1306 | } |
| 1307 | |
| 1308 | /* Perform operation OP with operands X and Y with sizes LEN_X and LEN_Y |
| 1309 | and byte orders BYTE_ORDER_X and BYTE_ORDER_Y, and store value in |
| 1310 | RESULT with size LEN_RESULT and byte order BYTE_ORDER_RESULT. */ |
| 1311 | static void |
| 1312 | decimal_binop (enum exp_opcode op, |
| 1313 | const gdb_byte *x, int len_x, enum bfd_endian byte_order_x, |
| 1314 | const gdb_byte *y, int len_y, enum bfd_endian byte_order_y, |
| 1315 | gdb_byte *result, int len_result, |
| 1316 | enum bfd_endian byte_order_result) |
| 1317 | { |
| 1318 | decContext set; |
| 1319 | decNumber number1, number2, number3; |
| 1320 | gdb_byte dec1[16], dec2[16], dec3[16]; |
| 1321 | |
| 1322 | match_endianness (x, len_x, byte_order_x, dec1); |
| 1323 | match_endianness (y, len_y, byte_order_y, dec2); |
| 1324 | |
| 1325 | decimal_to_number (dec1, len_x, &number1); |
| 1326 | decimal_to_number (dec2, len_y, &number2); |
| 1327 | |
| 1328 | set_decnumber_context (&set, len_result); |
| 1329 | |
| 1330 | switch (op) |
| 1331 | { |
| 1332 | case BINOP_ADD: |
| 1333 | decNumberAdd (&number3, &number1, &number2, &set); |
| 1334 | break; |
| 1335 | case BINOP_SUB: |
| 1336 | decNumberSubtract (&number3, &number1, &number2, &set); |
| 1337 | break; |
| 1338 | case BINOP_MUL: |
| 1339 | decNumberMultiply (&number3, &number1, &number2, &set); |
| 1340 | break; |
| 1341 | case BINOP_DIV: |
| 1342 | decNumberDivide (&number3, &number1, &number2, &set); |
| 1343 | break; |
| 1344 | case BINOP_EXP: |
| 1345 | decNumberPower (&number3, &number1, &number2, &set); |
| 1346 | break; |
| 1347 | default: |
| 1348 | error (_("Operation not valid for decimal floating point number.")); |
| 1349 | break; |
| 1350 | } |
| 1351 | |
| 1352 | /* Check for errors in the DFP operation. */ |
| 1353 | decimal_check_errors (&set); |
| 1354 | |
| 1355 | decimal_from_number (&number3, dec3, len_result); |
| 1356 | |
| 1357 | match_endianness (dec3, len_result, byte_order_result, result); |
| 1358 | } |
| 1359 | |
| 1360 | /* Returns true if X (which is LEN bytes wide) is the number zero. */ |
| 1361 | static int |
| 1362 | decimal_is_zero (const gdb_byte *x, int len, enum bfd_endian byte_order) |
| 1363 | { |
| 1364 | decNumber number; |
| 1365 | gdb_byte dec[16]; |
| 1366 | |
| 1367 | match_endianness (x, len, byte_order, dec); |
| 1368 | decimal_to_number (dec, len, &number); |
| 1369 | |
| 1370 | return decNumberIsZero (&number); |
| 1371 | } |
| 1372 | |
| 1373 | /* Compares two numbers numerically. If X is less than Y then the return value |
| 1374 | will be -1. If they are equal, then the return value will be 0. If X is |
| 1375 | greater than the Y then the return value will be 1. */ |
| 1376 | static int |
| 1377 | decimal_compare (const gdb_byte *x, int len_x, enum bfd_endian byte_order_x, |
| 1378 | const gdb_byte *y, int len_y, enum bfd_endian byte_order_y) |
| 1379 | { |
| 1380 | decNumber number1, number2, result; |
| 1381 | decContext set; |
| 1382 | gdb_byte dec1[16], dec2[16]; |
| 1383 | int len_result; |
| 1384 | |
| 1385 | match_endianness (x, len_x, byte_order_x, dec1); |
| 1386 | match_endianness (y, len_y, byte_order_y, dec2); |
| 1387 | |
| 1388 | decimal_to_number (dec1, len_x, &number1); |
| 1389 | decimal_to_number (dec2, len_y, &number2); |
| 1390 | |
| 1391 | /* Perform the comparison in the larger of the two sizes. */ |
| 1392 | len_result = len_x > len_y ? len_x : len_y; |
| 1393 | set_decnumber_context (&set, len_result); |
| 1394 | |
| 1395 | decNumberCompare (&result, &number1, &number2, &set); |
| 1396 | |
| 1397 | /* Check for errors in the DFP operation. */ |
| 1398 | decimal_check_errors (&set); |
| 1399 | |
| 1400 | if (decNumberIsNaN (&result)) |
| 1401 | error (_("Comparison with an invalid number (NaN).")); |
| 1402 | else if (decNumberIsZero (&result)) |
| 1403 | return 0; |
| 1404 | else if (decNumberIsNegative (&result)) |
| 1405 | return -1; |
| 1406 | else |
| 1407 | return 1; |
| 1408 | } |
| 1409 | |
| 1410 | /* Convert a decimal value from a decimal type with LEN_FROM bytes to a |
| 1411 | decimal type with LEN_TO bytes. */ |
| 1412 | static void |
| 1413 | decimal_convert (const gdb_byte *from, int len_from, |
| 1414 | enum bfd_endian byte_order_from, gdb_byte *to, int len_to, |
| 1415 | enum bfd_endian byte_order_to) |
| 1416 | { |
| 1417 | decNumber number; |
| 1418 | gdb_byte dec[16]; |
| 1419 | |
| 1420 | match_endianness (from, len_from, byte_order_from, dec); |
| 1421 | |
| 1422 | decimal_to_number (dec, len_from, &number); |
| 1423 | decimal_from_number (&number, dec, len_to); |
| 1424 | |
| 1425 | match_endianness (dec, len_to, byte_order_to, to); |
| 1426 | } |
| 1427 | |
| 1428 | |
| 1429 | /* Typed floating-point routines. These routines operate on floating-point |
| 1430 | values in target format, represented by a byte buffer interpreted as a |
| 1431 | "struct type", which may be either a binary or decimal floating-point |
| 1432 | type (TYPE_CODE_FLT or TYPE_CODE_DECFLOAT). */ |
| 1433 | |
| 1434 | /* Return whether the byte-stream ADDR holds a valid value of |
| 1435 | floating-point type TYPE. */ |
| 1436 | bool |
| 1437 | target_float_is_valid (const gdb_byte *addr, const struct type *type) |
| 1438 | { |
| 1439 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1440 | return floatformat_is_valid (floatformat_from_type (type), addr); |
| 1441 | |
| 1442 | if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT) |
| 1443 | return true; |
| 1444 | |
| 1445 | gdb_assert_not_reached ("unexpected type code"); |
| 1446 | } |
| 1447 | |
| 1448 | /* Return whether the byte-stream ADDR, interpreted as floating-point |
| 1449 | type TYPE, is numerically equal to zero (of either sign). */ |
| 1450 | bool |
| 1451 | target_float_is_zero (const gdb_byte *addr, const struct type *type) |
| 1452 | { |
| 1453 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1454 | return (floatformat_classify (floatformat_from_type (type), addr) |
| 1455 | == float_zero); |
| 1456 | |
| 1457 | if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT) |
| 1458 | return decimal_is_zero (addr, TYPE_LENGTH (type), |
| 1459 | gdbarch_byte_order (get_type_arch (type))); |
| 1460 | |
| 1461 | gdb_assert_not_reached ("unexpected type code"); |
| 1462 | } |
| 1463 | |
| 1464 | /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE, |
| 1465 | to a string, optionally using the print format FORMAT. */ |
| 1466 | std::string |
| 1467 | target_float_to_string (const gdb_byte *addr, const struct type *type, |
| 1468 | const char *format) |
| 1469 | { |
| 1470 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1471 | return floatformat_to_string (floatformat_from_type (type), addr, format); |
| 1472 | |
| 1473 | if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT) |
| 1474 | return decimal_to_string (addr, TYPE_LENGTH (type), |
| 1475 | gdbarch_byte_order (get_type_arch (type)), |
| 1476 | format); |
| 1477 | |
| 1478 | gdb_assert_not_reached ("unexpected type code"); |
| 1479 | } |
| 1480 | |
| 1481 | /* Parse string STRING into a target floating-number of type TYPE and |
| 1482 | store it as byte-stream ADDR. Return whether parsing succeeded. */ |
| 1483 | bool |
| 1484 | target_float_from_string (gdb_byte *addr, const struct type *type, |
| 1485 | const std::string &string) |
| 1486 | { |
| 1487 | /* Ensure possible padding bytes in the target buffer are zeroed out. */ |
| 1488 | memset (addr, 0, TYPE_LENGTH (type)); |
| 1489 | |
| 1490 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1491 | return floatformat_from_string (floatformat_from_type (type), addr, |
| 1492 | string); |
| 1493 | |
| 1494 | if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT) |
| 1495 | return decimal_from_string (addr, TYPE_LENGTH (type), |
| 1496 | gdbarch_byte_order (get_type_arch (type)), |
| 1497 | string); |
| 1498 | |
| 1499 | gdb_assert_not_reached ("unexpected type code"); |
| 1500 | } |
| 1501 | |
| 1502 | /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE, |
| 1503 | to an integer value (rounding towards zero). */ |
| 1504 | LONGEST |
| 1505 | target_float_to_longest (const gdb_byte *addr, const struct type *type) |
| 1506 | { |
| 1507 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1508 | return floatformat_to_longest (floatformat_from_type (type), addr); |
| 1509 | |
| 1510 | if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT) |
| 1511 | return decimal_to_longest (addr, TYPE_LENGTH (type), |
| 1512 | gdbarch_byte_order (get_type_arch (type))); |
| 1513 | |
| 1514 | gdb_assert_not_reached ("unexpected type code"); |
| 1515 | } |
| 1516 | |
| 1517 | /* Convert signed integer VAL to a target floating-number of type TYPE |
| 1518 | and store it as byte-stream ADDR. */ |
| 1519 | void |
| 1520 | target_float_from_longest (gdb_byte *addr, const struct type *type, |
| 1521 | LONGEST val) |
| 1522 | { |
| 1523 | /* Ensure possible padding bytes in the target buffer are zeroed out. */ |
| 1524 | memset (addr, 0, TYPE_LENGTH (type)); |
| 1525 | |
| 1526 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1527 | { |
| 1528 | floatformat_from_longest (floatformat_from_type (type), addr, val); |
| 1529 | return; |
| 1530 | } |
| 1531 | |
| 1532 | if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT) |
| 1533 | { |
| 1534 | decimal_from_longest (val, addr, TYPE_LENGTH (type), |
| 1535 | gdbarch_byte_order (get_type_arch (type))); |
| 1536 | return; |
| 1537 | } |
| 1538 | |
| 1539 | gdb_assert_not_reached ("unexpected type code"); |
| 1540 | } |
| 1541 | |
| 1542 | /* Convert unsigned integer VAL to a target floating-number of type TYPE |
| 1543 | and store it as byte-stream ADDR. */ |
| 1544 | void |
| 1545 | target_float_from_ulongest (gdb_byte *addr, const struct type *type, |
| 1546 | ULONGEST val) |
| 1547 | { |
| 1548 | /* Ensure possible padding bytes in the target buffer are zeroed out. */ |
| 1549 | memset (addr, 0, TYPE_LENGTH (type)); |
| 1550 | |
| 1551 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1552 | { |
| 1553 | floatformat_from_ulongest (floatformat_from_type (type), addr, val); |
| 1554 | return; |
| 1555 | } |
| 1556 | |
| 1557 | if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT) |
| 1558 | { |
| 1559 | decimal_from_ulongest (val, addr, TYPE_LENGTH (type), |
| 1560 | gdbarch_byte_order (get_type_arch (type))); |
| 1561 | return; |
| 1562 | } |
| 1563 | |
| 1564 | gdb_assert_not_reached ("unexpected type code"); |
| 1565 | } |
| 1566 | |
| 1567 | /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE, |
| 1568 | to a floating-point value in the host "double" format. */ |
| 1569 | double |
| 1570 | target_float_to_host_double (const gdb_byte *addr, |
| 1571 | const struct type *type) |
| 1572 | { |
| 1573 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1574 | return floatformat_to_host_double (floatformat_from_type (type), addr); |
| 1575 | |
| 1576 | /* We don't support conversions between target decimal floating-point |
| 1577 | types and the host double type here. */ |
| 1578 | |
| 1579 | gdb_assert_not_reached ("unexpected type code"); |
| 1580 | } |
| 1581 | |
| 1582 | /* Convert floating-point value VAL in the host "double" format to a target |
| 1583 | floating-number of type TYPE and store it as byte-stream ADDR. */ |
| 1584 | void |
| 1585 | target_float_from_host_double (gdb_byte *addr, const struct type *type, |
| 1586 | double val) |
| 1587 | { |
| 1588 | /* Ensure possible padding bytes in the target buffer are zeroed out. */ |
| 1589 | memset (addr, 0, TYPE_LENGTH (type)); |
| 1590 | |
| 1591 | if (TYPE_CODE (type) == TYPE_CODE_FLT) |
| 1592 | { |
| 1593 | floatformat_from_host_double (floatformat_from_type (type), addr, val); |
| 1594 | return; |
| 1595 | } |
| 1596 | |
| 1597 | /* We don't support conversions between target decimal floating-point |
| 1598 | types and the host double type here. */ |
| 1599 | |
| 1600 | gdb_assert_not_reached ("unexpected type code"); |
| 1601 | } |
| 1602 | |
| 1603 | /* Convert a floating-point number of type FROM_TYPE from the target |
| 1604 | byte-stream FROM to a floating-point number of type TO_TYPE, and |
| 1605 | store it to the target byte-stream TO. */ |
| 1606 | void |
| 1607 | target_float_convert (const gdb_byte *from, const struct type *from_type, |
| 1608 | gdb_byte *to, const struct type *to_type) |
| 1609 | { |
| 1610 | /* Ensure possible padding bytes in the target buffer are zeroed out. */ |
| 1611 | memset (to, 0, TYPE_LENGTH (to_type)); |
| 1612 | |
| 1613 | /* Use direct conversion routines if we have them. */ |
| 1614 | |
| 1615 | if (TYPE_CODE (from_type) == TYPE_CODE_FLT |
| 1616 | && TYPE_CODE (to_type) == TYPE_CODE_FLT) |
| 1617 | { |
| 1618 | floatformat_convert (from, floatformat_from_type (from_type), |
| 1619 | to, floatformat_from_type (to_type)); |
| 1620 | return; |
| 1621 | } |
| 1622 | |
| 1623 | if (TYPE_CODE (from_type) == TYPE_CODE_DECFLOAT |
| 1624 | && TYPE_CODE (to_type) == TYPE_CODE_DECFLOAT) |
| 1625 | { |
| 1626 | decimal_convert (from, TYPE_LENGTH (from_type), |
| 1627 | gdbarch_byte_order (get_type_arch (from_type)), |
| 1628 | to, TYPE_LENGTH (to_type), |
| 1629 | gdbarch_byte_order (get_type_arch (to_type))); |
| 1630 | return; |
| 1631 | } |
| 1632 | |
| 1633 | /* We cannot directly convert between binary and decimal floating-point |
| 1634 | types, so go via an intermediary string. */ |
| 1635 | |
| 1636 | if ((TYPE_CODE (from_type) == TYPE_CODE_FLT |
| 1637 | && TYPE_CODE (to_type) == TYPE_CODE_DECFLOAT) |
| 1638 | || (TYPE_CODE (from_type) == TYPE_CODE_DECFLOAT |
| 1639 | && TYPE_CODE (to_type) == TYPE_CODE_FLT)) |
| 1640 | { |
| 1641 | std::string str = target_float_to_string (from, from_type); |
| 1642 | target_float_from_string (to, to_type, str); |
| 1643 | return; |
| 1644 | } |
| 1645 | |
| 1646 | gdb_assert_not_reached ("unexpected type code"); |
| 1647 | } |
| 1648 | |
| 1649 | /* Perform the binary operation indicated by OPCODE, using as operands the |
| 1650 | target byte streams X and Y, interpreted as floating-point numbers of |
| 1651 | types TYPE_X and TYPE_Y, respectively. Convert the result to type |
| 1652 | TYPE_RES and store it into the byte-stream RES. |
| 1653 | |
| 1654 | The three types must either be all binary floating-point types, or else |
| 1655 | all decimal floating-point types. Binary and decimal floating-point |
| 1656 | types cannot be mixed within a single operation. */ |
| 1657 | void |
| 1658 | target_float_binop (enum exp_opcode opcode, |
| 1659 | const gdb_byte *x, const struct type *type_x, |
| 1660 | const gdb_byte *y, const struct type *type_y, |
| 1661 | gdb_byte *res, const struct type *type_res) |
| 1662 | { |
| 1663 | /* Ensure possible padding bytes in the target buffer are zeroed out. */ |
| 1664 | memset (res, 0, TYPE_LENGTH (type_res)); |
| 1665 | |
| 1666 | if (TYPE_CODE (type_res) == TYPE_CODE_FLT) |
| 1667 | { |
| 1668 | gdb_assert (TYPE_CODE (type_x) == TYPE_CODE_FLT); |
| 1669 | gdb_assert (TYPE_CODE (type_y) == TYPE_CODE_FLT); |
| 1670 | return floatformat_binop (opcode, |
| 1671 | floatformat_from_type (type_x), x, |
| 1672 | floatformat_from_type (type_y), y, |
| 1673 | floatformat_from_type (type_res), res); |
| 1674 | } |
| 1675 | |
| 1676 | if (TYPE_CODE (type_res) == TYPE_CODE_DECFLOAT) |
| 1677 | { |
| 1678 | gdb_assert (TYPE_CODE (type_x) == TYPE_CODE_DECFLOAT); |
| 1679 | gdb_assert (TYPE_CODE (type_y) == TYPE_CODE_DECFLOAT); |
| 1680 | return decimal_binop (opcode, |
| 1681 | x, TYPE_LENGTH (type_x), |
| 1682 | gdbarch_byte_order (get_type_arch (type_x)), |
| 1683 | y, TYPE_LENGTH (type_y), |
| 1684 | gdbarch_byte_order (get_type_arch (type_y)), |
| 1685 | res, TYPE_LENGTH (type_res), |
| 1686 | gdbarch_byte_order (get_type_arch (type_res))); |
| 1687 | } |
| 1688 | |
| 1689 | gdb_assert_not_reached ("unexpected type code"); |
| 1690 | } |
| 1691 | |
| 1692 | /* Compare the two target byte streams X and Y, interpreted as floating-point |
| 1693 | numbers of types TYPE_X and TYPE_Y, respectively. Return zero if X and Y |
| 1694 | are equal, -1 if X is less than Y, and 1 otherwise. |
| 1695 | |
| 1696 | The two types must either both be binary floating-point types, or else |
| 1697 | both be decimal floating-point types. Binary and decimal floating-point |
| 1698 | types cannot compared directly against each other. */ |
| 1699 | int |
| 1700 | target_float_compare (const gdb_byte *x, const struct type *type_x, |
| 1701 | const gdb_byte *y, const struct type *type_y) |
| 1702 | { |
| 1703 | if (TYPE_CODE (type_x) == TYPE_CODE_FLT) |
| 1704 | { |
| 1705 | gdb_assert (TYPE_CODE (type_y) == TYPE_CODE_FLT); |
| 1706 | return floatformat_compare (floatformat_from_type (type_x), x, |
| 1707 | floatformat_from_type (type_y), y); |
| 1708 | } |
| 1709 | |
| 1710 | if (TYPE_CODE (type_x) == TYPE_CODE_DECFLOAT) |
| 1711 | { |
| 1712 | gdb_assert (TYPE_CODE (type_y) == TYPE_CODE_DECFLOAT); |
| 1713 | return decimal_compare (x, TYPE_LENGTH (type_x), |
| 1714 | gdbarch_byte_order (get_type_arch (type_x)), |
| 1715 | y, TYPE_LENGTH (type_y), |
| 1716 | gdbarch_byte_order (get_type_arch (type_y))); |
| 1717 | } |
| 1718 | |
| 1719 | gdb_assert_not_reached ("unexpected type code"); |
| 1720 | } |
| 1721 | |