| 1 | /* Intel 387 floating point stuff. |
| 2 | Copyright (C) 1988, 1989, 1991, 1998, 1999 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GDB. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 19 | Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "frame.h" |
| 23 | #include "inferior.h" |
| 24 | #include "language.h" |
| 25 | #include "value.h" |
| 26 | #include "gdbcore.h" |
| 27 | #include "floatformat.h" |
| 28 | |
| 29 | |
| 30 | /* FIXME: Eliminate the next two functions when we have the time to |
| 31 | change all the callers. */ |
| 32 | |
| 33 | void i387_to_double PARAMS ((char *from, char *to)); |
| 34 | void double_to_i387 PARAMS ((char *from, char *to)); |
| 35 | |
| 36 | void |
| 37 | i387_to_double (from, to) |
| 38 | char *from; |
| 39 | char *to; |
| 40 | { |
| 41 | floatformat_to_double (&floatformat_i387_ext, from, (double *) to); |
| 42 | } |
| 43 | |
| 44 | void |
| 45 | double_to_i387 (from, to) |
| 46 | char *from; |
| 47 | char *to; |
| 48 | { |
| 49 | floatformat_from_double (&floatformat_i387_ext, (double *) from, to); |
| 50 | } |
| 51 | |
| 52 | \f |
| 53 | /* FIXME: The functions on this page are used by the old `info float' |
| 54 | implementations that a few of the i386 targets provide. These |
| 55 | functions should be removed if all of these have been converted to |
| 56 | use the generic implementation based on the new register file |
| 57 | layout. */ |
| 58 | |
| 59 | static void print_387_control_bits PARAMS ((unsigned int control)); |
| 60 | static void print_387_status_bits PARAMS ((unsigned int status)); |
| 61 | |
| 62 | static void |
| 63 | print_387_control_bits (control) |
| 64 | unsigned int control; |
| 65 | { |
| 66 | switch ((control >> 8) & 3) |
| 67 | { |
| 68 | case 0: |
| 69 | puts_unfiltered (" 24 bit; "); |
| 70 | break; |
| 71 | case 1: |
| 72 | puts_unfiltered (" (bad); "); |
| 73 | break; |
| 74 | case 2: |
| 75 | puts_unfiltered (" 53 bit; "); |
| 76 | break; |
| 77 | case 3: |
| 78 | puts_unfiltered (" 64 bit; "); |
| 79 | break; |
| 80 | } |
| 81 | switch ((control >> 10) & 3) |
| 82 | { |
| 83 | case 0: |
| 84 | puts_unfiltered ("NEAR; "); |
| 85 | break; |
| 86 | case 1: |
| 87 | puts_unfiltered ("DOWN; "); |
| 88 | break; |
| 89 | case 2: |
| 90 | puts_unfiltered ("UP; "); |
| 91 | break; |
| 92 | case 3: |
| 93 | puts_unfiltered ("CHOP; "); |
| 94 | break; |
| 95 | } |
| 96 | if (control & 0x3f) |
| 97 | { |
| 98 | puts_unfiltered ("mask"); |
| 99 | if (control & 0x0001) |
| 100 | puts_unfiltered (" INVAL"); |
| 101 | if (control & 0x0002) |
| 102 | puts_unfiltered (" DENOR"); |
| 103 | if (control & 0x0004) |
| 104 | puts_unfiltered (" DIVZ"); |
| 105 | if (control & 0x0008) |
| 106 | puts_unfiltered (" OVERF"); |
| 107 | if (control & 0x0010) |
| 108 | puts_unfiltered (" UNDER"); |
| 109 | if (control & 0x0020) |
| 110 | puts_unfiltered (" LOS"); |
| 111 | puts_unfiltered (";"); |
| 112 | } |
| 113 | |
| 114 | if (control & 0xe080) |
| 115 | warning ("\nreserved bits on: %s", |
| 116 | local_hex_string (control & 0xe080)); |
| 117 | } |
| 118 | |
| 119 | void |
| 120 | print_387_control_word (control) |
| 121 | unsigned int control; |
| 122 | { |
| 123 | printf_filtered ("control %s:", local_hex_string(control & 0xffff)); |
| 124 | print_387_control_bits (control); |
| 125 | puts_unfiltered ("\n"); |
| 126 | } |
| 127 | |
| 128 | static void |
| 129 | print_387_status_bits (status) |
| 130 | unsigned int status; |
| 131 | { |
| 132 | printf_unfiltered (" flags %d%d%d%d; ", |
| 133 | (status & 0x4000) != 0, |
| 134 | (status & 0x0400) != 0, |
| 135 | (status & 0x0200) != 0, |
| 136 | (status & 0x0100) != 0); |
| 137 | printf_unfiltered ("top %d; ", (status >> 11) & 7); |
| 138 | if (status & 0xff) |
| 139 | { |
| 140 | puts_unfiltered ("excep"); |
| 141 | if (status & 0x0001) puts_unfiltered (" INVAL"); |
| 142 | if (status & 0x0002) puts_unfiltered (" DENOR"); |
| 143 | if (status & 0x0004) puts_unfiltered (" DIVZ"); |
| 144 | if (status & 0x0008) puts_unfiltered (" OVERF"); |
| 145 | if (status & 0x0010) puts_unfiltered (" UNDER"); |
| 146 | if (status & 0x0020) puts_unfiltered (" LOS"); |
| 147 | if (status & 0x0040) puts_unfiltered (" STACK"); |
| 148 | } |
| 149 | } |
| 150 | |
| 151 | void |
| 152 | print_387_status_word (status) |
| 153 | unsigned int status; |
| 154 | { |
| 155 | printf_filtered ("status %s:", local_hex_string (status & 0xffff)); |
| 156 | print_387_status_bits (status); |
| 157 | puts_unfiltered ("\n"); |
| 158 | } |
| 159 | |
| 160 | \f |
| 161 | /* Implement the `info float' layout based on the register definitions |
| 162 | in `tm-i386.h'. */ |
| 163 | |
| 164 | /* Print the floating point number specified by RAW. */ |
| 165 | static void |
| 166 | print_i387_value (char *raw) |
| 167 | { |
| 168 | DOUBLEST value; |
| 169 | |
| 170 | floatformat_to_doublest (&floatformat_i387_ext, raw, &value); |
| 171 | |
| 172 | /* We try to print 19 digits. The last digit may or may not contain |
| 173 | garbage, but we'd better print one too many. We need enough room |
| 174 | to print the value, 1 position for the sign, 1 for the decimal |
| 175 | point, 19 for the digits and 6 for the exponent adds up to 27. */ |
| 176 | #ifdef PRINTF_HAS_LONG_DOUBLE |
| 177 | printf_filtered (" %-+27.19Lg", (long double) value); |
| 178 | #else |
| 179 | printf_filtered (" %-+27.19g", (double) value); |
| 180 | #endif |
| 181 | } |
| 182 | |
| 183 | /* Print the classification for the register contents RAW. */ |
| 184 | static void |
| 185 | print_i387_ext (unsigned char *raw) |
| 186 | { |
| 187 | int sign; |
| 188 | int integer; |
| 189 | unsigned int exponent; |
| 190 | unsigned long fraction[2]; |
| 191 | |
| 192 | sign = raw[9] & 0x80; |
| 193 | integer = raw[7] & 0x80; |
| 194 | exponent = (((raw[9] & 0x7f) << 8) | raw[8]); |
| 195 | fraction[0] = ((raw[3] << 24) | (raw[2] << 16) | (raw[1] << 8) | raw[0]); |
| 196 | fraction[1] = (((raw[7] & 0x7f) << 24) | (raw[6] << 16) |
| 197 | | (raw[5] << 8) | raw[4]); |
| 198 | |
| 199 | if (exponent == 0x7fff && integer) |
| 200 | { |
| 201 | if (fraction[0] == 0x00000000 && fraction[1] == 0x00000000) |
| 202 | /* Infinity. */ |
| 203 | printf_filtered (" %cInf", (sign ? '-' : '+')); |
| 204 | else if (sign && fraction[0] == 0x00000000 && fraction[1] == 0x40000000) |
| 205 | /* Real Indefinite (QNaN). */ |
| 206 | puts_unfiltered (" Real Indefinite (QNaN)"); |
| 207 | else if (fraction[1] & 0x40000000) |
| 208 | /* QNaN. */ |
| 209 | puts_filtered (" QNaN"); |
| 210 | else |
| 211 | /* SNaN. */ |
| 212 | puts_filtered (" SNaN"); |
| 213 | } |
| 214 | else if (exponent < 0x7fff && exponent > 0x0000 && integer) |
| 215 | /* Normal. */ |
| 216 | print_i387_value (raw); |
| 217 | else if (exponent == 0x0000) |
| 218 | { |
| 219 | /* Denormal or zero. */ |
| 220 | print_i387_value (raw); |
| 221 | |
| 222 | if (integer) |
| 223 | /* Pseudo-denormal. */ |
| 224 | puts_filtered (" Pseudo-denormal"); |
| 225 | else if (fraction[0] || fraction[1]) |
| 226 | /* Denormal. */ |
| 227 | puts_filtered (" Denormal"); |
| 228 | } |
| 229 | else |
| 230 | /* Unsupported. */ |
| 231 | puts_filtered (" Unsupported"); |
| 232 | } |
| 233 | |
| 234 | /* Print the status word STATUS. */ |
| 235 | static void |
| 236 | print_i387_status_word (unsigned int status) |
| 237 | { |
| 238 | printf_filtered ("Status Word: %s", |
| 239 | local_hex_string_custom (status, "04")); |
| 240 | puts_filtered (" "); |
| 241 | printf_filtered (" %s", (status & 0x0001) ? "IE" : " "); |
| 242 | printf_filtered (" %s", (status & 0x0002) ? "DE" : " "); |
| 243 | printf_filtered (" %s", (status & 0x0004) ? "ZE" : " "); |
| 244 | printf_filtered (" %s", (status & 0x0008) ? "OE" : " "); |
| 245 | printf_filtered (" %s", (status & 0x0010) ? "UE" : " "); |
| 246 | printf_filtered (" %s", (status & 0x0020) ? "PE" : " "); |
| 247 | puts_filtered (" "); |
| 248 | printf_filtered (" %s", (status & 0x0080) ? "ES" : " "); |
| 249 | puts_filtered (" "); |
| 250 | printf_filtered (" %s", (status & 0x0080) ? "SF" : " "); |
| 251 | puts_filtered (" "); |
| 252 | printf_filtered (" %s", (status & 0x0100) ? "C0" : " "); |
| 253 | printf_filtered (" %s", (status & 0x0200) ? "C1" : " "); |
| 254 | printf_filtered (" %s", (status & 0x0400) ? "C2" : " "); |
| 255 | printf_filtered (" %s", (status & 0x4000) ? "C3" : " "); |
| 256 | |
| 257 | puts_filtered ("\n"); |
| 258 | |
| 259 | printf_filtered (" TOP: %d\n", ((status >> 11) & 7)); |
| 260 | } |
| 261 | |
| 262 | /* Print the control word CONTROL. */ |
| 263 | static void |
| 264 | print_i387_control_word (unsigned int control) |
| 265 | { |
| 266 | printf_filtered ("Control Word: %s", |
| 267 | local_hex_string_custom (control, "04")); |
| 268 | puts_filtered (" "); |
| 269 | printf_filtered (" %s", (control & 0x0001) ? "IM" : " "); |
| 270 | printf_filtered (" %s", (control & 0x0002) ? "DM" : " "); |
| 271 | printf_filtered (" %s", (control & 0x0004) ? "ZM" : " "); |
| 272 | printf_filtered (" %s", (control & 0x0008) ? "OM" : " "); |
| 273 | printf_filtered (" %s", (control & 0x0010) ? "UM" : " "); |
| 274 | printf_filtered (" %s", (control & 0x0020) ? "PM" : " "); |
| 275 | |
| 276 | puts_filtered ("\n"); |
| 277 | |
| 278 | puts_filtered (" PC: "); |
| 279 | switch ((control >> 8) & 3) |
| 280 | { |
| 281 | case 0: |
| 282 | puts_filtered ("Single Precision (24-bits)\n"); |
| 283 | break; |
| 284 | case 1: |
| 285 | puts_filtered ("Reserved\n"); |
| 286 | break; |
| 287 | case 2: |
| 288 | puts_filtered ("Double Precision (53-bits)\n"); |
| 289 | break; |
| 290 | case 3: |
| 291 | puts_filtered ("Extended Precision (64-bits)\n"); |
| 292 | break; |
| 293 | } |
| 294 | |
| 295 | puts_filtered (" RC: "); |
| 296 | switch ((control >> 10) & 3) |
| 297 | { |
| 298 | case 0: |
| 299 | puts_filtered ("Round to nearest\n"); |
| 300 | break; |
| 301 | case 1: |
| 302 | puts_filtered ("Round down\n"); |
| 303 | break; |
| 304 | case 2: |
| 305 | puts_filtered ("Round up\n"); |
| 306 | break; |
| 307 | case 3: |
| 308 | puts_filtered ("Round toward zero\n"); |
| 309 | break; |
| 310 | } |
| 311 | } |
| 312 | |
| 313 | /* Print out the i387 floating poin state. */ |
| 314 | void |
| 315 | i387_float_info (void) |
| 316 | { |
| 317 | unsigned int fctrl; |
| 318 | unsigned int fstat; |
| 319 | unsigned int ftag; |
| 320 | unsigned int fiseg; |
| 321 | unsigned int fioff; |
| 322 | unsigned int foseg; |
| 323 | unsigned int fooff; |
| 324 | unsigned int fop; |
| 325 | int fpreg; |
| 326 | int top; |
| 327 | |
| 328 | fctrl = read_register (FCTRL_REGNUM); |
| 329 | fstat = read_register (FSTAT_REGNUM); |
| 330 | ftag = read_register (FTAG_REGNUM); |
| 331 | fiseg = read_register (FCS_REGNUM); |
| 332 | fioff = read_register (FCOFF_REGNUM); |
| 333 | foseg = read_register (FDS_REGNUM); |
| 334 | fooff = read_register (FDOFF_REGNUM); |
| 335 | fop = read_register (FOP_REGNUM); |
| 336 | |
| 337 | top = ((fstat >> 11) & 7); |
| 338 | |
| 339 | for (fpreg = 7; fpreg >= 0; fpreg--) |
| 340 | { |
| 341 | unsigned char raw[FPU_REG_RAW_SIZE]; |
| 342 | int tag = (ftag >> (fpreg * 2)) & 3; |
| 343 | int i; |
| 344 | |
| 345 | printf_filtered ("%sR%d: ", fpreg == top ? "=>" : " ", fpreg); |
| 346 | |
| 347 | switch (tag) |
| 348 | { |
| 349 | case 0: |
| 350 | puts_filtered ("Valid "); |
| 351 | break; |
| 352 | case 1: |
| 353 | puts_filtered ("Zero "); |
| 354 | break; |
| 355 | case 2: |
| 356 | puts_filtered ("Special "); |
| 357 | break; |
| 358 | case 3: |
| 359 | puts_filtered ("Empty "); |
| 360 | break; |
| 361 | } |
| 362 | |
| 363 | read_register_gen ((fpreg + 8 - top) % 8 + FP0_REGNUM, raw); |
| 364 | |
| 365 | puts_filtered ("0x"); |
| 366 | for (i = 9; i >= 0; i--) |
| 367 | printf_filtered ("%02x", raw[i]); |
| 368 | |
| 369 | if (tag != 3) |
| 370 | print_i387_ext (raw); |
| 371 | |
| 372 | puts_filtered ("\n"); |
| 373 | } |
| 374 | |
| 375 | puts_filtered ("\n"); |
| 376 | |
| 377 | print_i387_status_word (fstat); |
| 378 | print_i387_control_word (fctrl); |
| 379 | printf_filtered ("Tag Word: %s\n", |
| 380 | local_hex_string_custom (ftag, "04")); |
| 381 | printf_filtered ("Instruction Pointer: %s:", |
| 382 | local_hex_string_custom (fiseg, "02")); |
| 383 | printf_filtered ("%s\n", local_hex_string_custom (fioff, "08")); |
| 384 | printf_filtered ("Operand Pointer: %s:", |
| 385 | local_hex_string_custom (foseg, "02")); |
| 386 | printf_filtered ("%s\n", local_hex_string_custom (fooff, "08")); |
| 387 | printf_filtered ("Opcode: %s\n", |
| 388 | local_hex_string_custom (fop ? (fop | 0xd800) : 0, "04")); |
| 389 | } |
| 390 | |
| 391 | \f |
| 392 | /* FIXME: The functions on this page are used to provide `long double' |
| 393 | support for Linux. However, the approach does not seem to be the |
| 394 | right one, and we are planning to solve this in a way that should |
| 395 | work for all i386 targets. These functions will disappear in the |
| 396 | near future, so please don't use them. */ |
| 397 | #ifdef LD_I387 |
| 398 | int |
| 399 | i387_extract_floating (PTR addr, int len, DOUBLEST *dretptr) |
| 400 | { |
| 401 | if (len == TARGET_LONG_DOUBLE_BIT / 8) |
| 402 | { |
| 403 | if (HOST_LONG_DOUBLE_FORMAT == TARGET_LONG_DOUBLE_FORMAT) |
| 404 | { |
| 405 | DOUBLEST retval; |
| 406 | |
| 407 | memcpy (dretptr, addr, sizeof (retval)); |
| 408 | } |
| 409 | else |
| 410 | floatformat_to_doublest (TARGET_LONG_DOUBLE_FORMAT, addr, dretptr); |
| 411 | |
| 412 | return 1; |
| 413 | } |
| 414 | else |
| 415 | return 0; |
| 416 | } |
| 417 | |
| 418 | int |
| 419 | i387_store_floating (PTR addr, int len, DOUBLEST val) |
| 420 | { |
| 421 | if (len == TARGET_LONG_DOUBLE_BIT / 8) |
| 422 | { |
| 423 | /* This `if' may be totally stupid. I just put it in here to be |
| 424 | absolutely sure I'm preserving the semantics of the code I'm |
| 425 | frobbing, while I try to maintain portability boundaries; I |
| 426 | don't actually know exactly what it's doing. -JimB, May 1999 */ |
| 427 | if (HOST_LONG_DOUBLE_FORMAT == TARGET_LONG_DOUBLE_FORMAT) |
| 428 | memcpy (addr, &val, sizeof (val)); |
| 429 | else |
| 430 | floatformat_from_doublest (TARGET_LONG_DOUBLE_FORMAT, &val, addr); |
| 431 | |
| 432 | return 1; |
| 433 | } |
| 434 | else |
| 435 | return 0; |
| 436 | } |
| 437 | #endif /* LD_I387 */ |