| 1 | /* Intel 387 floating point stuff. |
| 2 | |
| 3 | Copyright 1988, 1989, 1991, 1992, 1993, 1994, 1998, 1999, 2000, |
| 4 | 2001, 2002, 2003, 2004 Free Software Foundation, Inc. |
| 5 | |
| 6 | This file is part of GDB. |
| 7 | |
| 8 | This program is free software; you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation; either version 2 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | This program is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this program; if not, write to the Free Software |
| 20 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 21 | Boston, MA 02111-1307, USA. */ |
| 22 | |
| 23 | #include "defs.h" |
| 24 | #include "doublest.h" |
| 25 | #include "floatformat.h" |
| 26 | #include "frame.h" |
| 27 | #include "gdbcore.h" |
| 28 | #include "inferior.h" |
| 29 | #include "language.h" |
| 30 | #include "regcache.h" |
| 31 | #include "value.h" |
| 32 | |
| 33 | #include "gdb_assert.h" |
| 34 | #include "gdb_string.h" |
| 35 | |
| 36 | #include "i386-tdep.h" |
| 37 | #include "i387-tdep.h" |
| 38 | |
| 39 | /* Implement the `info float' layout based on the register definitions |
| 40 | in `tm-i386.h'. */ |
| 41 | |
| 42 | /* Print the floating point number specified by RAW. */ |
| 43 | |
| 44 | static void |
| 45 | print_i387_value (char *raw, struct ui_file *file) |
| 46 | { |
| 47 | DOUBLEST value; |
| 48 | |
| 49 | /* Using extract_typed_floating here might affect the representation |
| 50 | of certain numbers such as NaNs, even if GDB is running natively. |
| 51 | This is fine since our caller already detects such special |
| 52 | numbers and we print the hexadecimal representation anyway. */ |
| 53 | value = extract_typed_floating (raw, builtin_type_i387_ext); |
| 54 | |
| 55 | /* We try to print 19 digits. The last digit may or may not contain |
| 56 | garbage, but we'd better print one too many. We need enough room |
| 57 | to print the value, 1 position for the sign, 1 for the decimal |
| 58 | point, 19 for the digits and 6 for the exponent adds up to 27. */ |
| 59 | #ifdef PRINTF_HAS_LONG_DOUBLE |
| 60 | fprintf_filtered (file, " %-+27.19Lg", (long double) value); |
| 61 | #else |
| 62 | fprintf_filtered (file, " %-+27.19g", (double) value); |
| 63 | #endif |
| 64 | } |
| 65 | |
| 66 | /* Print the classification for the register contents RAW. */ |
| 67 | |
| 68 | static void |
| 69 | print_i387_ext (unsigned char *raw, struct ui_file *file) |
| 70 | { |
| 71 | int sign; |
| 72 | int integer; |
| 73 | unsigned int exponent; |
| 74 | unsigned long fraction[2]; |
| 75 | |
| 76 | sign = raw[9] & 0x80; |
| 77 | integer = raw[7] & 0x80; |
| 78 | exponent = (((raw[9] & 0x7f) << 8) | raw[8]); |
| 79 | fraction[0] = ((raw[3] << 24) | (raw[2] << 16) | (raw[1] << 8) | raw[0]); |
| 80 | fraction[1] = (((raw[7] & 0x7f) << 24) | (raw[6] << 16) |
| 81 | | (raw[5] << 8) | raw[4]); |
| 82 | |
| 83 | if (exponent == 0x7fff && integer) |
| 84 | { |
| 85 | if (fraction[0] == 0x00000000 && fraction[1] == 0x00000000) |
| 86 | /* Infinity. */ |
| 87 | fprintf_filtered (file, " %cInf", (sign ? '-' : '+')); |
| 88 | else if (sign && fraction[0] == 0x00000000 && fraction[1] == 0x40000000) |
| 89 | /* Real Indefinite (QNaN). */ |
| 90 | fputs_unfiltered (" Real Indefinite (QNaN)", file); |
| 91 | else if (fraction[1] & 0x40000000) |
| 92 | /* QNaN. */ |
| 93 | fputs_filtered (" QNaN", file); |
| 94 | else |
| 95 | /* SNaN. */ |
| 96 | fputs_filtered (" SNaN", file); |
| 97 | } |
| 98 | else if (exponent < 0x7fff && exponent > 0x0000 && integer) |
| 99 | /* Normal. */ |
| 100 | print_i387_value (raw, file); |
| 101 | else if (exponent == 0x0000) |
| 102 | { |
| 103 | /* Denormal or zero. */ |
| 104 | print_i387_value (raw, file); |
| 105 | |
| 106 | if (integer) |
| 107 | /* Pseudo-denormal. */ |
| 108 | fputs_filtered (" Pseudo-denormal", file); |
| 109 | else if (fraction[0] || fraction[1]) |
| 110 | /* Denormal. */ |
| 111 | fputs_filtered (" Denormal", file); |
| 112 | } |
| 113 | else |
| 114 | /* Unsupported. */ |
| 115 | fputs_filtered (" Unsupported", file); |
| 116 | } |
| 117 | |
| 118 | /* Print the status word STATUS. */ |
| 119 | |
| 120 | static void |
| 121 | print_i387_status_word (unsigned int status, struct ui_file *file) |
| 122 | { |
| 123 | fprintf_filtered (file, "Status Word: %s", |
| 124 | hex_string_custom (status, 4)); |
| 125 | fputs_filtered (" ", file); |
| 126 | fprintf_filtered (file, " %s", (status & 0x0001) ? "IE" : " "); |
| 127 | fprintf_filtered (file, " %s", (status & 0x0002) ? "DE" : " "); |
| 128 | fprintf_filtered (file, " %s", (status & 0x0004) ? "ZE" : " "); |
| 129 | fprintf_filtered (file, " %s", (status & 0x0008) ? "OE" : " "); |
| 130 | fprintf_filtered (file, " %s", (status & 0x0010) ? "UE" : " "); |
| 131 | fprintf_filtered (file, " %s", (status & 0x0020) ? "PE" : " "); |
| 132 | fputs_filtered (" ", file); |
| 133 | fprintf_filtered (file, " %s", (status & 0x0080) ? "ES" : " "); |
| 134 | fputs_filtered (" ", file); |
| 135 | fprintf_filtered (file, " %s", (status & 0x0040) ? "SF" : " "); |
| 136 | fputs_filtered (" ", file); |
| 137 | fprintf_filtered (file, " %s", (status & 0x0100) ? "C0" : " "); |
| 138 | fprintf_filtered (file, " %s", (status & 0x0200) ? "C1" : " "); |
| 139 | fprintf_filtered (file, " %s", (status & 0x0400) ? "C2" : " "); |
| 140 | fprintf_filtered (file, " %s", (status & 0x4000) ? "C3" : " "); |
| 141 | |
| 142 | fputs_filtered ("\n", file); |
| 143 | |
| 144 | fprintf_filtered (file, |
| 145 | " TOP: %d\n", ((status >> 11) & 7)); |
| 146 | } |
| 147 | |
| 148 | /* Print the control word CONTROL. */ |
| 149 | |
| 150 | static void |
| 151 | print_i387_control_word (unsigned int control, struct ui_file *file) |
| 152 | { |
| 153 | fprintf_filtered (file, "Control Word: %s", |
| 154 | hex_string_custom (control, 4)); |
| 155 | fputs_filtered (" ", file); |
| 156 | fprintf_filtered (file, " %s", (control & 0x0001) ? "IM" : " "); |
| 157 | fprintf_filtered (file, " %s", (control & 0x0002) ? "DM" : " "); |
| 158 | fprintf_filtered (file, " %s", (control & 0x0004) ? "ZM" : " "); |
| 159 | fprintf_filtered (file, " %s", (control & 0x0008) ? "OM" : " "); |
| 160 | fprintf_filtered (file, " %s", (control & 0x0010) ? "UM" : " "); |
| 161 | fprintf_filtered (file, " %s", (control & 0x0020) ? "PM" : " "); |
| 162 | |
| 163 | fputs_filtered ("\n", file); |
| 164 | |
| 165 | fputs_filtered (" PC: ", file); |
| 166 | switch ((control >> 8) & 3) |
| 167 | { |
| 168 | case 0: |
| 169 | fputs_filtered ("Single Precision (24-bits)\n", file); |
| 170 | break; |
| 171 | case 1: |
| 172 | fputs_filtered ("Reserved\n", file); |
| 173 | break; |
| 174 | case 2: |
| 175 | fputs_filtered ("Double Precision (53-bits)\n", file); |
| 176 | break; |
| 177 | case 3: |
| 178 | fputs_filtered ("Extended Precision (64-bits)\n", file); |
| 179 | break; |
| 180 | } |
| 181 | |
| 182 | fputs_filtered (" RC: ", file); |
| 183 | switch ((control >> 10) & 3) |
| 184 | { |
| 185 | case 0: |
| 186 | fputs_filtered ("Round to nearest\n", file); |
| 187 | break; |
| 188 | case 1: |
| 189 | fputs_filtered ("Round down\n", file); |
| 190 | break; |
| 191 | case 2: |
| 192 | fputs_filtered ("Round up\n", file); |
| 193 | break; |
| 194 | case 3: |
| 195 | fputs_filtered ("Round toward zero\n", file); |
| 196 | break; |
| 197 | } |
| 198 | } |
| 199 | |
| 200 | /* Print out the i387 floating point state. Note that we ignore FRAME |
| 201 | in the code below. That's OK since floating-point registers are |
| 202 | never saved on the stack. */ |
| 203 | |
| 204 | void |
| 205 | i387_print_float_info (struct gdbarch *gdbarch, struct ui_file *file, |
| 206 | struct frame_info *frame, const char *args) |
| 207 | { |
| 208 | struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (frame)); |
| 209 | char buf[4]; |
| 210 | ULONGEST fctrl; |
| 211 | ULONGEST fstat; |
| 212 | ULONGEST ftag; |
| 213 | ULONGEST fiseg; |
| 214 | ULONGEST fioff; |
| 215 | ULONGEST foseg; |
| 216 | ULONGEST fooff; |
| 217 | ULONGEST fop; |
| 218 | int fpreg; |
| 219 | int top; |
| 220 | |
| 221 | gdb_assert (gdbarch == get_frame_arch (frame)); |
| 222 | |
| 223 | /* Define I387_ST0_REGNUM such that we use the proper definitions |
| 224 | for FRAME's architecture. */ |
| 225 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 226 | |
| 227 | fctrl = get_frame_register_unsigned (frame, I387_FCTRL_REGNUM); |
| 228 | fstat = get_frame_register_unsigned (frame, I387_FSTAT_REGNUM); |
| 229 | ftag = get_frame_register_unsigned (frame, I387_FTAG_REGNUM); |
| 230 | fiseg = get_frame_register_unsigned (frame, I387_FISEG_REGNUM); |
| 231 | fioff = get_frame_register_unsigned (frame, I387_FIOFF_REGNUM); |
| 232 | foseg = get_frame_register_unsigned (frame, I387_FOSEG_REGNUM); |
| 233 | fooff = get_frame_register_unsigned (frame, I387_FOOFF_REGNUM); |
| 234 | fop = get_frame_register_unsigned (frame, I387_FOP_REGNUM); |
| 235 | |
| 236 | top = ((fstat >> 11) & 7); |
| 237 | |
| 238 | for (fpreg = 7; fpreg >= 0; fpreg--) |
| 239 | { |
| 240 | unsigned char raw[I386_MAX_REGISTER_SIZE]; |
| 241 | int tag = (ftag >> (fpreg * 2)) & 3; |
| 242 | int i; |
| 243 | |
| 244 | fprintf_filtered (file, "%sR%d: ", fpreg == top ? "=>" : " ", fpreg); |
| 245 | |
| 246 | switch (tag) |
| 247 | { |
| 248 | case 0: |
| 249 | fputs_filtered ("Valid ", file); |
| 250 | break; |
| 251 | case 1: |
| 252 | fputs_filtered ("Zero ", file); |
| 253 | break; |
| 254 | case 2: |
| 255 | fputs_filtered ("Special ", file); |
| 256 | break; |
| 257 | case 3: |
| 258 | fputs_filtered ("Empty ", file); |
| 259 | break; |
| 260 | } |
| 261 | |
| 262 | get_frame_register (frame, (fpreg + 8 - top) % 8 + I387_ST0_REGNUM, raw); |
| 263 | |
| 264 | fputs_filtered ("0x", file); |
| 265 | for (i = 9; i >= 0; i--) |
| 266 | fprintf_filtered (file, "%02x", raw[i]); |
| 267 | |
| 268 | if (tag != 3) |
| 269 | print_i387_ext (raw, file); |
| 270 | |
| 271 | fputs_filtered ("\n", file); |
| 272 | } |
| 273 | |
| 274 | fputs_filtered ("\n", file); |
| 275 | |
| 276 | print_i387_status_word (fstat, file); |
| 277 | print_i387_control_word (fctrl, file); |
| 278 | fprintf_filtered (file, "Tag Word: %s\n", |
| 279 | hex_string_custom (ftag, 4)); |
| 280 | fprintf_filtered (file, "Instruction Pointer: %s:", |
| 281 | hex_string_custom (fiseg, 2)); |
| 282 | fprintf_filtered (file, "%s\n", hex_string_custom (fioff, 8)); |
| 283 | fprintf_filtered (file, "Operand Pointer: %s:", |
| 284 | hex_string_custom (foseg, 2)); |
| 285 | fprintf_filtered (file, "%s\n", hex_string_custom (fooff, 8)); |
| 286 | fprintf_filtered (file, "Opcode: %s\n", |
| 287 | hex_string_custom (fop ? (fop | 0xd800) : 0, 4)); |
| 288 | |
| 289 | #undef I387_ST0_REGNUM |
| 290 | } |
| 291 | \f |
| 292 | |
| 293 | /* Read a value of type TYPE from register REGNUM in frame FRAME, and |
| 294 | return its contents in TO. */ |
| 295 | |
| 296 | void |
| 297 | i387_register_to_value (struct frame_info *frame, int regnum, |
| 298 | struct type *type, void *to) |
| 299 | { |
| 300 | char from[I386_MAX_REGISTER_SIZE]; |
| 301 | |
| 302 | gdb_assert (i386_fp_regnum_p (regnum)); |
| 303 | |
| 304 | /* We only support floating-point values. */ |
| 305 | if (TYPE_CODE (type) != TYPE_CODE_FLT) |
| 306 | { |
| 307 | warning ("Cannot convert floating-point register value " |
| 308 | "to non-floating-point type."); |
| 309 | return; |
| 310 | } |
| 311 | |
| 312 | /* Convert to TYPE. This should be a no-op if TYPE is equivalent to |
| 313 | the extended floating-point format used by the FPU. */ |
| 314 | get_frame_register (frame, regnum, from); |
| 315 | convert_typed_floating (from, builtin_type_i387_ext, to, type); |
| 316 | } |
| 317 | |
| 318 | /* Write the contents FROM of a value of type TYPE into register |
| 319 | REGNUM in frame FRAME. */ |
| 320 | |
| 321 | void |
| 322 | i387_value_to_register (struct frame_info *frame, int regnum, |
| 323 | struct type *type, const void *from) |
| 324 | { |
| 325 | char to[I386_MAX_REGISTER_SIZE]; |
| 326 | |
| 327 | gdb_assert (i386_fp_regnum_p (regnum)); |
| 328 | |
| 329 | /* We only support floating-point values. */ |
| 330 | if (TYPE_CODE (type) != TYPE_CODE_FLT) |
| 331 | { |
| 332 | warning ("Cannot convert non-floating-point type " |
| 333 | "to floating-point register value."); |
| 334 | return; |
| 335 | } |
| 336 | |
| 337 | /* Convert from TYPE. This should be a no-op if TYPE is equivalent |
| 338 | to the extended floating-point format used by the FPU. */ |
| 339 | convert_typed_floating (from, type, to, builtin_type_i387_ext); |
| 340 | put_frame_register (frame, regnum, to); |
| 341 | } |
| 342 | \f |
| 343 | |
| 344 | /* Handle FSAVE and FXSAVE formats. */ |
| 345 | |
| 346 | /* FIXME: kettenis/20030927: The functions below should accept a |
| 347 | `regcache' argument, but I don't want to change the function |
| 348 | signature just yet. There's some band-aid in the functions below |
| 349 | in the form of the `regcache' local variables. This will ease the |
| 350 | transition later on. */ |
| 351 | |
| 352 | /* At fsave_offset[REGNUM] you'll find the offset to the location in |
| 353 | the data structure used by the "fsave" instruction where GDB |
| 354 | register REGNUM is stored. */ |
| 355 | |
| 356 | static int fsave_offset[] = |
| 357 | { |
| 358 | 28 + 0 * 10, /* %st(0) ... */ |
| 359 | 28 + 1 * 10, |
| 360 | 28 + 2 * 10, |
| 361 | 28 + 3 * 10, |
| 362 | 28 + 4 * 10, |
| 363 | 28 + 5 * 10, |
| 364 | 28 + 6 * 10, |
| 365 | 28 + 7 * 10, /* ... %st(7). */ |
| 366 | 0, /* `fctrl' (16 bits). */ |
| 367 | 4, /* `fstat' (16 bits). */ |
| 368 | 8, /* `ftag' (16 bits). */ |
| 369 | 16, /* `fiseg' (16 bits). */ |
| 370 | 12, /* `fioff'. */ |
| 371 | 24, /* `foseg' (16 bits). */ |
| 372 | 20, /* `fooff'. */ |
| 373 | 18 /* `fop' (bottom 11 bits). */ |
| 374 | }; |
| 375 | |
| 376 | #define FSAVE_ADDR(fsave, regnum) \ |
| 377 | (fsave + fsave_offset[regnum - I387_ST0_REGNUM]) |
| 378 | \f |
| 379 | |
| 380 | /* Fill register REGNUM in REGCACHE with the appropriate value from |
| 381 | *FSAVE. This function masks off any of the reserved bits in |
| 382 | *FSAVE. */ |
| 383 | |
| 384 | void |
| 385 | i387_supply_fsave (struct regcache *regcache, int regnum, const void *fsave) |
| 386 | { |
| 387 | struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache)); |
| 388 | const char *regs = fsave; |
| 389 | int i; |
| 390 | |
| 391 | gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM); |
| 392 | |
| 393 | /* Define I387_ST0_REGNUM and I387_NUM_XMM_REGS such that we use the |
| 394 | proper definitions for REGCACHE's architecture. */ |
| 395 | |
| 396 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 397 | #define I387_NUM_XMM_REGS tdep->num_xmm_regs |
| 398 | |
| 399 | for (i = I387_ST0_REGNUM; i < I387_XMM0_REGNUM; i++) |
| 400 | if (regnum == -1 || regnum == i) |
| 401 | { |
| 402 | if (fsave == NULL) |
| 403 | { |
| 404 | regcache_raw_supply (regcache, i, NULL); |
| 405 | continue; |
| 406 | } |
| 407 | |
| 408 | /* Most of the FPU control registers occupy only 16 bits in the |
| 409 | fsave area. Give those a special treatment. */ |
| 410 | if (i >= I387_FCTRL_REGNUM |
| 411 | && i != I387_FIOFF_REGNUM && i != I387_FOOFF_REGNUM) |
| 412 | { |
| 413 | unsigned char val[4]; |
| 414 | |
| 415 | memcpy (val, FSAVE_ADDR (regs, i), 2); |
| 416 | val[2] = val[3] = 0; |
| 417 | if (i == I387_FOP_REGNUM) |
| 418 | val[1] &= ((1 << 3) - 1); |
| 419 | regcache_raw_supply (regcache, i, val); |
| 420 | } |
| 421 | else |
| 422 | regcache_raw_supply (regcache, i, FSAVE_ADDR (regs, i)); |
| 423 | } |
| 424 | |
| 425 | /* Provide dummy values for the SSE registers. */ |
| 426 | for (i = I387_XMM0_REGNUM; i < I387_MXCSR_REGNUM; i++) |
| 427 | if (regnum == -1 || regnum == i) |
| 428 | regcache_raw_supply (regcache, i, NULL); |
| 429 | if (regnum == -1 || regnum == I387_MXCSR_REGNUM) |
| 430 | { |
| 431 | char buf[4]; |
| 432 | |
| 433 | store_unsigned_integer (buf, 4, 0x1f80); |
| 434 | regcache_raw_supply (regcache, I387_MXCSR_REGNUM, buf); |
| 435 | } |
| 436 | |
| 437 | #undef I387_ST0_REGNUM |
| 438 | #undef I387_NUM_XMM_REGS |
| 439 | } |
| 440 | |
| 441 | /* Fill register REGNUM (if it is a floating-point register) in *FSAVE |
| 442 | with the value from REGCACHE. If REGNUM is -1, do this for all |
| 443 | registers. This function doesn't touch any of the reserved bits in |
| 444 | *FSAVE. */ |
| 445 | |
| 446 | void |
| 447 | i387_collect_fsave (const struct regcache *regcache, int regnum, void *fsave) |
| 448 | { |
| 449 | struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); |
| 450 | char *regs = fsave; |
| 451 | int i; |
| 452 | |
| 453 | gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM); |
| 454 | |
| 455 | /* Define I387_ST0_REGNUM such that we use the proper definitions |
| 456 | for REGCACHE's architecture. */ |
| 457 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 458 | |
| 459 | for (i = I387_ST0_REGNUM; i < I387_XMM0_REGNUM; i++) |
| 460 | if (regnum == -1 || regnum == i) |
| 461 | { |
| 462 | /* Most of the FPU control registers occupy only 16 bits in |
| 463 | the fsave area. Give those a special treatment. */ |
| 464 | if (i >= I387_FCTRL_REGNUM |
| 465 | && i != I387_FIOFF_REGNUM && i != I387_FOOFF_REGNUM) |
| 466 | { |
| 467 | unsigned char buf[4]; |
| 468 | |
| 469 | regcache_raw_collect (regcache, i, buf); |
| 470 | |
| 471 | if (i == I387_FOP_REGNUM) |
| 472 | { |
| 473 | /* The opcode occupies only 11 bits. Make sure we |
| 474 | don't touch the other bits. */ |
| 475 | buf[1] &= ((1 << 3) - 1); |
| 476 | buf[1] |= ((FSAVE_ADDR (regs, i))[1] & ~((1 << 3) - 1)); |
| 477 | } |
| 478 | memcpy (FSAVE_ADDR (regs, i), buf, 2); |
| 479 | } |
| 480 | else |
| 481 | regcache_raw_collect (regcache, i, FSAVE_ADDR (regs, i)); |
| 482 | } |
| 483 | #undef I387_ST0_REGNUM |
| 484 | } |
| 485 | |
| 486 | /* Fill register REGNUM (if it is a floating-point register) in *FSAVE |
| 487 | with the value in GDB's register cache. If REGNUM is -1, do this |
| 488 | for all registers. This function doesn't touch any of the reserved |
| 489 | bits in *FSAVE. */ |
| 490 | |
| 491 | void |
| 492 | i387_fill_fsave (void *fsave, int regnum) |
| 493 | { |
| 494 | i387_collect_fsave (current_regcache, regnum, fsave); |
| 495 | } |
| 496 | \f |
| 497 | |
| 498 | /* At fxsave_offset[REGNUM] you'll find the offset to the location in |
| 499 | the data structure used by the "fxsave" instruction where GDB |
| 500 | register REGNUM is stored. */ |
| 501 | |
| 502 | static int fxsave_offset[] = |
| 503 | { |
| 504 | 32, /* %st(0) through ... */ |
| 505 | 48, |
| 506 | 64, |
| 507 | 80, |
| 508 | 96, |
| 509 | 112, |
| 510 | 128, |
| 511 | 144, /* ... %st(7) (80 bits each). */ |
| 512 | 0, /* `fctrl' (16 bits). */ |
| 513 | 2, /* `fstat' (16 bits). */ |
| 514 | 4, /* `ftag' (16 bits). */ |
| 515 | 12, /* `fiseg' (16 bits). */ |
| 516 | 8, /* `fioff'. */ |
| 517 | 20, /* `foseg' (16 bits). */ |
| 518 | 16, /* `fooff'. */ |
| 519 | 6, /* `fop' (bottom 11 bits). */ |
| 520 | 160 + 0 * 16, /* %xmm0 through ... */ |
| 521 | 160 + 1 * 16, |
| 522 | 160 + 2 * 16, |
| 523 | 160 + 3 * 16, |
| 524 | 160 + 4 * 16, |
| 525 | 160 + 5 * 16, |
| 526 | 160 + 6 * 16, |
| 527 | 160 + 7 * 16, |
| 528 | 160 + 8 * 16, |
| 529 | 160 + 9 * 16, |
| 530 | 160 + 10 * 16, |
| 531 | 160 + 11 * 16, |
| 532 | 160 + 12 * 16, |
| 533 | 160 + 13 * 16, |
| 534 | 160 + 14 * 16, |
| 535 | 160 + 15 * 16, /* ... %xmm15 (128 bits each). */ |
| 536 | }; |
| 537 | |
| 538 | #define FXSAVE_ADDR(fxsave, regnum) \ |
| 539 | (fxsave + fxsave_offset[regnum - I387_ST0_REGNUM]) |
| 540 | |
| 541 | /* We made an unfortunate choice in putting %mxcsr after the SSE |
| 542 | registers %xmm0-%xmm7 instead of before, since it makes supporting |
| 543 | the registers %xmm8-%xmm15 on AMD64 a bit involved. Therefore we |
| 544 | don't include the offset for %mxcsr here above. */ |
| 545 | |
| 546 | #define FXSAVE_MXCSR_ADDR(fxsave) (fxsave + 24) |
| 547 | |
| 548 | static int i387_tag (const unsigned char *raw); |
| 549 | \f |
| 550 | |
| 551 | /* Fill register REGNUM in REGCACHE with the appropriate |
| 552 | floating-point or SSE register value from *FXSAVE. This function |
| 553 | masks off any of the reserved bits in *FXSAVE. */ |
| 554 | |
| 555 | void |
| 556 | i387_supply_fxsave (struct regcache *regcache, int regnum, const void *fxsave) |
| 557 | { |
| 558 | struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache)); |
| 559 | const char *regs = fxsave; |
| 560 | int i; |
| 561 | |
| 562 | gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM); |
| 563 | gdb_assert (tdep->num_xmm_regs > 0); |
| 564 | |
| 565 | /* Define I387_ST0_REGNUM and I387_NUM_XMM_REGS such that we use the |
| 566 | proper definitions for REGCACHE's architecture. */ |
| 567 | |
| 568 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 569 | #define I387_NUM_XMM_REGS tdep->num_xmm_regs |
| 570 | |
| 571 | for (i = I387_ST0_REGNUM; i < I387_MXCSR_REGNUM; i++) |
| 572 | if (regnum == -1 || regnum == i) |
| 573 | { |
| 574 | if (regs == NULL) |
| 575 | { |
| 576 | regcache_raw_supply (regcache, i, NULL); |
| 577 | continue; |
| 578 | } |
| 579 | |
| 580 | /* Most of the FPU control registers occupy only 16 bits in |
| 581 | the fxsave area. Give those a special treatment. */ |
| 582 | if (i >= I387_FCTRL_REGNUM && i < I387_XMM0_REGNUM |
| 583 | && i != I387_FIOFF_REGNUM && i != I387_FOOFF_REGNUM) |
| 584 | { |
| 585 | unsigned char val[4]; |
| 586 | |
| 587 | memcpy (val, FXSAVE_ADDR (regs, i), 2); |
| 588 | val[2] = val[3] = 0; |
| 589 | if (i == I387_FOP_REGNUM) |
| 590 | val[1] &= ((1 << 3) - 1); |
| 591 | else if (i== I387_FTAG_REGNUM) |
| 592 | { |
| 593 | /* The fxsave area contains a simplified version of |
| 594 | the tag word. We have to look at the actual 80-bit |
| 595 | FP data to recreate the traditional i387 tag word. */ |
| 596 | |
| 597 | unsigned long ftag = 0; |
| 598 | int fpreg; |
| 599 | int top; |
| 600 | |
| 601 | top = ((FXSAVE_ADDR (regs, I387_FSTAT_REGNUM))[1] >> 3); |
| 602 | top &= 0x7; |
| 603 | |
| 604 | for (fpreg = 7; fpreg >= 0; fpreg--) |
| 605 | { |
| 606 | int tag; |
| 607 | |
| 608 | if (val[0] & (1 << fpreg)) |
| 609 | { |
| 610 | int regnum = (fpreg + 8 - top) % 8 + I387_ST0_REGNUM; |
| 611 | tag = i387_tag (FXSAVE_ADDR (regs, regnum)); |
| 612 | } |
| 613 | else |
| 614 | tag = 3; /* Empty */ |
| 615 | |
| 616 | ftag |= tag << (2 * fpreg); |
| 617 | } |
| 618 | val[0] = ftag & 0xff; |
| 619 | val[1] = (ftag >> 8) & 0xff; |
| 620 | } |
| 621 | regcache_raw_supply (regcache, i, val); |
| 622 | } |
| 623 | else |
| 624 | regcache_raw_supply (regcache, i, FXSAVE_ADDR (regs, i)); |
| 625 | } |
| 626 | |
| 627 | if (regnum == I387_MXCSR_REGNUM || regnum == -1) |
| 628 | { |
| 629 | if (regs == NULL) |
| 630 | regcache_raw_supply (regcache, I387_MXCSR_REGNUM, NULL); |
| 631 | else |
| 632 | regcache_raw_supply (regcache, I387_MXCSR_REGNUM, |
| 633 | FXSAVE_MXCSR_ADDR (regs)); |
| 634 | } |
| 635 | |
| 636 | #undef I387_ST0_REGNUM |
| 637 | #undef I387_NUM_XMM_REGS |
| 638 | } |
| 639 | |
| 640 | /* Fill register REGNUM (if it is a floating-point or SSE register) in |
| 641 | *FXSAVE with the value from REGCACHE. If REGNUM is -1, do this for |
| 642 | all registers. This function doesn't touch any of the reserved |
| 643 | bits in *FXSAVE. */ |
| 644 | |
| 645 | void |
| 646 | i387_collect_fxsave (const struct regcache *regcache, int regnum, void *fxsave) |
| 647 | { |
| 648 | struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch); |
| 649 | char *regs = fxsave; |
| 650 | int i; |
| 651 | |
| 652 | gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM); |
| 653 | gdb_assert (tdep->num_xmm_regs > 0); |
| 654 | |
| 655 | /* Define I387_ST0_REGNUM and I387_NUM_XMM_REGS such that we use the |
| 656 | proper definitions for REGCACHE's architecture. */ |
| 657 | |
| 658 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 659 | #define I387_NUM_XMM_REGS tdep->num_xmm_regs |
| 660 | |
| 661 | for (i = I387_ST0_REGNUM; i < I387_MXCSR_REGNUM; i++) |
| 662 | if (regnum == -1 || regnum == i) |
| 663 | { |
| 664 | /* Most of the FPU control registers occupy only 16 bits in |
| 665 | the fxsave area. Give those a special treatment. */ |
| 666 | if (i >= I387_FCTRL_REGNUM && i < I387_XMM0_REGNUM |
| 667 | && i != I387_FIOFF_REGNUM && i != I387_FOOFF_REGNUM) |
| 668 | { |
| 669 | unsigned char buf[4]; |
| 670 | |
| 671 | regcache_raw_collect (regcache, i, buf); |
| 672 | |
| 673 | if (i == I387_FOP_REGNUM) |
| 674 | { |
| 675 | /* The opcode occupies only 11 bits. Make sure we |
| 676 | don't touch the other bits. */ |
| 677 | buf[1] &= ((1 << 3) - 1); |
| 678 | buf[1] |= ((FXSAVE_ADDR (regs, i))[1] & ~((1 << 3) - 1)); |
| 679 | } |
| 680 | else if (i == I387_FTAG_REGNUM) |
| 681 | { |
| 682 | /* Converting back is much easier. */ |
| 683 | |
| 684 | unsigned short ftag; |
| 685 | int fpreg; |
| 686 | |
| 687 | ftag = (buf[1] << 8) | buf[0]; |
| 688 | buf[0] = 0; |
| 689 | buf[1] = 0; |
| 690 | |
| 691 | for (fpreg = 7; fpreg >= 0; fpreg--) |
| 692 | { |
| 693 | int tag = (ftag >> (fpreg * 2)) & 3; |
| 694 | |
| 695 | if (tag != 3) |
| 696 | buf[0] |= (1 << fpreg); |
| 697 | } |
| 698 | } |
| 699 | memcpy (FXSAVE_ADDR (regs, i), buf, 2); |
| 700 | } |
| 701 | else |
| 702 | regcache_raw_collect (regcache, i, FXSAVE_ADDR (regs, i)); |
| 703 | } |
| 704 | |
| 705 | if (regnum == I387_MXCSR_REGNUM || regnum == -1) |
| 706 | regcache_raw_collect (regcache, I387_MXCSR_REGNUM, |
| 707 | FXSAVE_MXCSR_ADDR (regs)); |
| 708 | |
| 709 | #undef I387_ST0_REGNUM |
| 710 | #undef I387_NUM_XMM_REGS |
| 711 | } |
| 712 | |
| 713 | /* Fill register REGNUM (if it is a floating-point or SSE register) in |
| 714 | *FXSAVE with the value in GDB's register cache. If REGNUM is -1, do |
| 715 | this for all registers. This function doesn't touch any of the |
| 716 | reserved bits in *FXSAVE. */ |
| 717 | |
| 718 | void |
| 719 | i387_fill_fxsave (void *fxsave, int regnum) |
| 720 | { |
| 721 | i387_collect_fxsave (current_regcache, regnum, fxsave); |
| 722 | } |
| 723 | |
| 724 | /* Recreate the FTW (tag word) valid bits from the 80-bit FP data in |
| 725 | *RAW. */ |
| 726 | |
| 727 | static int |
| 728 | i387_tag (const unsigned char *raw) |
| 729 | { |
| 730 | int integer; |
| 731 | unsigned int exponent; |
| 732 | unsigned long fraction[2]; |
| 733 | |
| 734 | integer = raw[7] & 0x80; |
| 735 | exponent = (((raw[9] & 0x7f) << 8) | raw[8]); |
| 736 | fraction[0] = ((raw[3] << 24) | (raw[2] << 16) | (raw[1] << 8) | raw[0]); |
| 737 | fraction[1] = (((raw[7] & 0x7f) << 24) | (raw[6] << 16) |
| 738 | | (raw[5] << 8) | raw[4]); |
| 739 | |
| 740 | if (exponent == 0x7fff) |
| 741 | { |
| 742 | /* Special. */ |
| 743 | return (2); |
| 744 | } |
| 745 | else if (exponent == 0x0000) |
| 746 | { |
| 747 | if (fraction[0] == 0x0000 && fraction[1] == 0x0000 && !integer) |
| 748 | { |
| 749 | /* Zero. */ |
| 750 | return (1); |
| 751 | } |
| 752 | else |
| 753 | { |
| 754 | /* Special. */ |
| 755 | return (2); |
| 756 | } |
| 757 | } |
| 758 | else |
| 759 | { |
| 760 | if (integer) |
| 761 | { |
| 762 | /* Valid. */ |
| 763 | return (0); |
| 764 | } |
| 765 | else |
| 766 | { |
| 767 | /* Special. */ |
| 768 | return (2); |
| 769 | } |
| 770 | } |
| 771 | } |
| 772 | |
| 773 | /* Prepare the FPU stack in REGCACHE for a function return. */ |
| 774 | |
| 775 | void |
| 776 | i387_return_value (struct gdbarch *gdbarch, struct regcache *regcache) |
| 777 | { |
| 778 | struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch); |
| 779 | ULONGEST fstat; |
| 780 | |
| 781 | /* Define I387_ST0_REGNUM such that we use the proper |
| 782 | definitions for the architecture. */ |
| 783 | #define I387_ST0_REGNUM tdep->st0_regnum |
| 784 | |
| 785 | /* Set the top of the floating-point register stack to 7. The |
| 786 | actual value doesn't really matter, but 7 is what a normal |
| 787 | function return would end up with if the program started out with |
| 788 | a freshly initialized FPU. */ |
| 789 | regcache_raw_read_unsigned (regcache, I387_FSTAT_REGNUM, &fstat); |
| 790 | fstat |= (7 << 11); |
| 791 | regcache_raw_write_unsigned (regcache, I387_FSTAT_REGNUM, fstat); |
| 792 | |
| 793 | /* Mark %st(1) through %st(7) as empty. Since we set the top of the |
| 794 | floating-point register stack to 7, the appropriate value for the |
| 795 | tag word is 0x3fff. */ |
| 796 | regcache_raw_write_unsigned (regcache, I387_FTAG_REGNUM, 0x3fff); |
| 797 | |
| 798 | #undef I387_ST0_REGNUM |
| 799 | } |