add "this" pointers to more target APIs
[deliverable/binutils-gdb.git] / gdb / i387-tdep.c
1 /* Intel 387 floating point stuff.
2
3 Copyright (C) 1988-2014 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 "doublest.h"
22 #include "floatformat.h"
23 #include "frame.h"
24 #include "gdbcore.h"
25 #include "inferior.h"
26 #include "language.h"
27 #include "regcache.h"
28 #include "value.h"
29
30 #include "gdb_assert.h"
31 #include <string.h>
32
33 #include "i386-tdep.h"
34 #include "i387-tdep.h"
35 #include "i386-xstate.h"
36
37 /* Print the floating point number specified by RAW. */
38
39 static void
40 print_i387_value (struct gdbarch *gdbarch,
41 const gdb_byte *raw, struct ui_file *file)
42 {
43 DOUBLEST value;
44
45 /* Using extract_typed_floating here might affect the representation
46 of certain numbers such as NaNs, even if GDB is running natively.
47 This is fine since our caller already detects such special
48 numbers and we print the hexadecimal representation anyway. */
49 value = extract_typed_floating (raw, i387_ext_type (gdbarch));
50
51 /* We try to print 19 digits. The last digit may or may not contain
52 garbage, but we'd better print one too many. We need enough room
53 to print the value, 1 position for the sign, 1 for the decimal
54 point, 19 for the digits and 6 for the exponent adds up to 27. */
55 #ifdef PRINTF_HAS_LONG_DOUBLE
56 fprintf_filtered (file, " %-+27.19Lg", (long double) value);
57 #else
58 fprintf_filtered (file, " %-+27.19g", (double) value);
59 #endif
60 }
61
62 /* Print the classification for the register contents RAW. */
63
64 static void
65 print_i387_ext (struct gdbarch *gdbarch,
66 const gdb_byte *raw, struct ui_file *file)
67 {
68 int sign;
69 int integer;
70 unsigned int exponent;
71 unsigned long fraction[2];
72
73 sign = raw[9] & 0x80;
74 integer = raw[7] & 0x80;
75 exponent = (((raw[9] & 0x7f) << 8) | raw[8]);
76 fraction[0] = ((raw[3] << 24) | (raw[2] << 16) | (raw[1] << 8) | raw[0]);
77 fraction[1] = (((raw[7] & 0x7f) << 24) | (raw[6] << 16)
78 | (raw[5] << 8) | raw[4]);
79
80 if (exponent == 0x7fff && integer)
81 {
82 if (fraction[0] == 0x00000000 && fraction[1] == 0x00000000)
83 /* Infinity. */
84 fprintf_filtered (file, " %cInf", (sign ? '-' : '+'));
85 else if (sign && fraction[0] == 0x00000000 && fraction[1] == 0x40000000)
86 /* Real Indefinite (QNaN). */
87 fputs_unfiltered (" Real Indefinite (QNaN)", file);
88 else if (fraction[1] & 0x40000000)
89 /* QNaN. */
90 fputs_filtered (" QNaN", file);
91 else
92 /* SNaN. */
93 fputs_filtered (" SNaN", file);
94 }
95 else if (exponent < 0x7fff && exponent > 0x0000 && integer)
96 /* Normal. */
97 print_i387_value (gdbarch, raw, file);
98 else if (exponent == 0x0000)
99 {
100 /* Denormal or zero. */
101 print_i387_value (gdbarch, raw, file);
102
103 if (integer)
104 /* Pseudo-denormal. */
105 fputs_filtered (" Pseudo-denormal", file);
106 else if (fraction[0] || fraction[1])
107 /* Denormal. */
108 fputs_filtered (" Denormal", file);
109 }
110 else
111 /* Unsupported. */
112 fputs_filtered (" Unsupported", file);
113 }
114
115 /* Print the status word STATUS. If STATUS_P is false, then STATUS
116 was unavailable. */
117
118 static void
119 print_i387_status_word (int status_p,
120 unsigned int status, struct ui_file *file)
121 {
122 fprintf_filtered (file, "Status Word: ");
123 if (!status_p)
124 {
125 fprintf_filtered (file, "%s\n", _("<unavailable>"));
126 return;
127 }
128
129 fprintf_filtered (file, "%s", hex_string_custom (status, 4));
130 fputs_filtered (" ", file);
131 fprintf_filtered (file, " %s", (status & 0x0001) ? "IE" : " ");
132 fprintf_filtered (file, " %s", (status & 0x0002) ? "DE" : " ");
133 fprintf_filtered (file, " %s", (status & 0x0004) ? "ZE" : " ");
134 fprintf_filtered (file, " %s", (status & 0x0008) ? "OE" : " ");
135 fprintf_filtered (file, " %s", (status & 0x0010) ? "UE" : " ");
136 fprintf_filtered (file, " %s", (status & 0x0020) ? "PE" : " ");
137 fputs_filtered (" ", file);
138 fprintf_filtered (file, " %s", (status & 0x0080) ? "ES" : " ");
139 fputs_filtered (" ", file);
140 fprintf_filtered (file, " %s", (status & 0x0040) ? "SF" : " ");
141 fputs_filtered (" ", file);
142 fprintf_filtered (file, " %s", (status & 0x0100) ? "C0" : " ");
143 fprintf_filtered (file, " %s", (status & 0x0200) ? "C1" : " ");
144 fprintf_filtered (file, " %s", (status & 0x0400) ? "C2" : " ");
145 fprintf_filtered (file, " %s", (status & 0x4000) ? "C3" : " ");
146
147 fputs_filtered ("\n", file);
148
149 fprintf_filtered (file,
150 " TOP: %d\n", ((status >> 11) & 7));
151 }
152
153 /* Print the control word CONTROL. If CONTROL_P is false, then
154 CONTROL was unavailable. */
155
156 static void
157 print_i387_control_word (int control_p,
158 unsigned int control, struct ui_file *file)
159 {
160 fprintf_filtered (file, "Control Word: ");
161 if (!control_p)
162 {
163 fprintf_filtered (file, "%s\n", _("<unavailable>"));
164 return;
165 }
166
167 fprintf_filtered (file, "%s", hex_string_custom (control, 4));
168 fputs_filtered (" ", file);
169 fprintf_filtered (file, " %s", (control & 0x0001) ? "IM" : " ");
170 fprintf_filtered (file, " %s", (control & 0x0002) ? "DM" : " ");
171 fprintf_filtered (file, " %s", (control & 0x0004) ? "ZM" : " ");
172 fprintf_filtered (file, " %s", (control & 0x0008) ? "OM" : " ");
173 fprintf_filtered (file, " %s", (control & 0x0010) ? "UM" : " ");
174 fprintf_filtered (file, " %s", (control & 0x0020) ? "PM" : " ");
175
176 fputs_filtered ("\n", file);
177
178 fputs_filtered (" PC: ", file);
179 switch ((control >> 8) & 3)
180 {
181 case 0:
182 fputs_filtered ("Single Precision (24-bits)\n", file);
183 break;
184 case 1:
185 fputs_filtered ("Reserved\n", file);
186 break;
187 case 2:
188 fputs_filtered ("Double Precision (53-bits)\n", file);
189 break;
190 case 3:
191 fputs_filtered ("Extended Precision (64-bits)\n", file);
192 break;
193 }
194
195 fputs_filtered (" RC: ", file);
196 switch ((control >> 10) & 3)
197 {
198 case 0:
199 fputs_filtered ("Round to nearest\n", file);
200 break;
201 case 1:
202 fputs_filtered ("Round down\n", file);
203 break;
204 case 2:
205 fputs_filtered ("Round up\n", file);
206 break;
207 case 3:
208 fputs_filtered ("Round toward zero\n", file);
209 break;
210 }
211 }
212
213 /* Print out the i387 floating point state. Note that we ignore FRAME
214 in the code below. That's OK since floating-point registers are
215 never saved on the stack. */
216
217 void
218 i387_print_float_info (struct gdbarch *gdbarch, struct ui_file *file,
219 struct frame_info *frame, const char *args)
220 {
221 struct gdbarch_tdep *tdep = gdbarch_tdep (get_frame_arch (frame));
222 ULONGEST fctrl;
223 int fctrl_p;
224 ULONGEST fstat;
225 int fstat_p;
226 ULONGEST ftag;
227 int ftag_p;
228 ULONGEST fiseg;
229 int fiseg_p;
230 ULONGEST fioff;
231 int fioff_p;
232 ULONGEST foseg;
233 int foseg_p;
234 ULONGEST fooff;
235 int fooff_p;
236 ULONGEST fop;
237 int fop_p;
238 int fpreg;
239 int top;
240
241 gdb_assert (gdbarch == get_frame_arch (frame));
242
243 fctrl_p = read_frame_register_unsigned (frame,
244 I387_FCTRL_REGNUM (tdep), &fctrl);
245 fstat_p = read_frame_register_unsigned (frame,
246 I387_FSTAT_REGNUM (tdep), &fstat);
247 ftag_p = read_frame_register_unsigned (frame,
248 I387_FTAG_REGNUM (tdep), &ftag);
249 fiseg_p = read_frame_register_unsigned (frame,
250 I387_FISEG_REGNUM (tdep), &fiseg);
251 fioff_p = read_frame_register_unsigned (frame,
252 I387_FIOFF_REGNUM (tdep), &fioff);
253 foseg_p = read_frame_register_unsigned (frame,
254 I387_FOSEG_REGNUM (tdep), &foseg);
255 fooff_p = read_frame_register_unsigned (frame,
256 I387_FOOFF_REGNUM (tdep), &fooff);
257 fop_p = read_frame_register_unsigned (frame,
258 I387_FOP_REGNUM (tdep), &fop);
259
260 if (fstat_p)
261 {
262 top = ((fstat >> 11) & 7);
263
264 for (fpreg = 7; fpreg >= 0; fpreg--)
265 {
266 struct value *regval;
267 int regnum;
268 int i;
269 int tag = -1;
270
271 fprintf_filtered (file, "%sR%d: ", fpreg == top ? "=>" : " ", fpreg);
272
273 if (ftag_p)
274 {
275 tag = (ftag >> (fpreg * 2)) & 3;
276
277 switch (tag)
278 {
279 case 0:
280 fputs_filtered ("Valid ", file);
281 break;
282 case 1:
283 fputs_filtered ("Zero ", file);
284 break;
285 case 2:
286 fputs_filtered ("Special ", file);
287 break;
288 case 3:
289 fputs_filtered ("Empty ", file);
290 break;
291 }
292 }
293 else
294 fputs_filtered ("Unknown ", file);
295
296 regnum = (fpreg + 8 - top) % 8 + I387_ST0_REGNUM (tdep);
297 regval = get_frame_register_value (frame, regnum);
298
299 if (value_entirely_available (regval))
300 {
301 const gdb_byte *raw = value_contents (regval);
302
303 fputs_filtered ("0x", file);
304 for (i = 9; i >= 0; i--)
305 fprintf_filtered (file, "%02x", raw[i]);
306
307 if (tag != -1 && tag != 3)
308 print_i387_ext (gdbarch, raw, file);
309 }
310 else
311 fprintf_filtered (file, "%s", _("<unavailable>"));
312
313 fputs_filtered ("\n", file);
314 }
315 }
316
317 fputs_filtered ("\n", file);
318 print_i387_status_word (fstat_p, fstat, file);
319 print_i387_control_word (fctrl_p, fctrl, file);
320 fprintf_filtered (file, "Tag Word: %s\n",
321 ftag_p ? hex_string_custom (ftag, 4) : _("<unavailable>"));
322 fprintf_filtered (file, "Instruction Pointer: %s:",
323 fiseg_p ? hex_string_custom (fiseg, 2) : _("<unavailable>"));
324 fprintf_filtered (file, "%s\n",
325 fioff_p ? hex_string_custom (fioff, 8) : _("<unavailable>"));
326 fprintf_filtered (file, "Operand Pointer: %s:",
327 foseg_p ? hex_string_custom (foseg, 2) : _("<unavailable>"));
328 fprintf_filtered (file, "%s\n",
329 fooff_p ? hex_string_custom (fooff, 8) : _("<unavailable>"));
330 fprintf_filtered (file, "Opcode: %s\n",
331 fop_p
332 ? (hex_string_custom (fop ? (fop | 0xd800) : 0, 4))
333 : _("<unavailable>"));
334 }
335 \f
336
337 /* Return nonzero if a value of type TYPE stored in register REGNUM
338 needs any special handling. */
339
340 int
341 i387_convert_register_p (struct gdbarch *gdbarch, int regnum,
342 struct type *type)
343 {
344 if (i386_fp_regnum_p (gdbarch, regnum))
345 {
346 /* Floating point registers must be converted unless we are
347 accessing them in their hardware type. */
348 if (type == i387_ext_type (gdbarch))
349 return 0;
350 else
351 return 1;
352 }
353
354 return 0;
355 }
356
357 /* Read a value of type TYPE from register REGNUM in frame FRAME, and
358 return its contents in TO. */
359
360 int
361 i387_register_to_value (struct frame_info *frame, int regnum,
362 struct type *type, gdb_byte *to,
363 int *optimizedp, int *unavailablep)
364 {
365 struct gdbarch *gdbarch = get_frame_arch (frame);
366 gdb_byte from[I386_MAX_REGISTER_SIZE];
367
368 gdb_assert (i386_fp_regnum_p (gdbarch, regnum));
369
370 /* We only support floating-point values. */
371 if (TYPE_CODE (type) != TYPE_CODE_FLT)
372 {
373 warning (_("Cannot convert floating-point register value "
374 "to non-floating-point type."));
375 *optimizedp = *unavailablep = 0;
376 return 0;
377 }
378
379 /* Convert to TYPE. */
380 if (!get_frame_register_bytes (frame, regnum, 0, TYPE_LENGTH (type),
381 from, optimizedp, unavailablep))
382 return 0;
383
384 convert_typed_floating (from, i387_ext_type (gdbarch), to, type);
385 *optimizedp = *unavailablep = 0;
386 return 1;
387 }
388
389 /* Write the contents FROM of a value of type TYPE into register
390 REGNUM in frame FRAME. */
391
392 void
393 i387_value_to_register (struct frame_info *frame, int regnum,
394 struct type *type, const gdb_byte *from)
395 {
396 struct gdbarch *gdbarch = get_frame_arch (frame);
397 gdb_byte to[I386_MAX_REGISTER_SIZE];
398
399 gdb_assert (i386_fp_regnum_p (gdbarch, regnum));
400
401 /* We only support floating-point values. */
402 if (TYPE_CODE (type) != TYPE_CODE_FLT)
403 {
404 warning (_("Cannot convert non-floating-point type "
405 "to floating-point register value."));
406 return;
407 }
408
409 /* Convert from TYPE. */
410 convert_typed_floating (from, type, to, i387_ext_type (gdbarch));
411 put_frame_register (frame, regnum, to);
412 }
413 \f
414
415 /* Handle FSAVE and FXSAVE formats. */
416
417 /* At fsave_offset[REGNUM] you'll find the offset to the location in
418 the data structure used by the "fsave" instruction where GDB
419 register REGNUM is stored. */
420
421 static int fsave_offset[] =
422 {
423 28 + 0 * 10, /* %st(0) ... */
424 28 + 1 * 10,
425 28 + 2 * 10,
426 28 + 3 * 10,
427 28 + 4 * 10,
428 28 + 5 * 10,
429 28 + 6 * 10,
430 28 + 7 * 10, /* ... %st(7). */
431 0, /* `fctrl' (16 bits). */
432 4, /* `fstat' (16 bits). */
433 8, /* `ftag' (16 bits). */
434 16, /* `fiseg' (16 bits). */
435 12, /* `fioff'. */
436 24, /* `foseg' (16 bits). */
437 20, /* `fooff'. */
438 18 /* `fop' (bottom 11 bits). */
439 };
440
441 #define FSAVE_ADDR(tdep, fsave, regnum) \
442 (fsave + fsave_offset[regnum - I387_ST0_REGNUM (tdep)])
443 \f
444
445 /* Fill register REGNUM in REGCACHE with the appropriate value from
446 *FSAVE. This function masks off any of the reserved bits in
447 *FSAVE. */
448
449 void
450 i387_supply_fsave (struct regcache *regcache, int regnum, const void *fsave)
451 {
452 struct gdbarch *gdbarch = get_regcache_arch (regcache);
453 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
454 enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
455 const gdb_byte *regs = fsave;
456 int i;
457
458 gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM);
459
460 for (i = I387_ST0_REGNUM (tdep); i < I387_XMM0_REGNUM (tdep); i++)
461 if (regnum == -1 || regnum == i)
462 {
463 if (fsave == NULL)
464 {
465 regcache_raw_supply (regcache, i, NULL);
466 continue;
467 }
468
469 /* Most of the FPU control registers occupy only 16 bits in the
470 fsave area. Give those a special treatment. */
471 if (i >= I387_FCTRL_REGNUM (tdep)
472 && i != I387_FIOFF_REGNUM (tdep) && i != I387_FOOFF_REGNUM (tdep))
473 {
474 gdb_byte val[4];
475
476 memcpy (val, FSAVE_ADDR (tdep, regs, i), 2);
477 val[2] = val[3] = 0;
478 if (i == I387_FOP_REGNUM (tdep))
479 val[1] &= ((1 << 3) - 1);
480 regcache_raw_supply (regcache, i, val);
481 }
482 else
483 regcache_raw_supply (regcache, i, FSAVE_ADDR (tdep, regs, i));
484 }
485
486 /* Provide dummy values for the SSE registers. */
487 for (i = I387_XMM0_REGNUM (tdep); i < I387_MXCSR_REGNUM (tdep); i++)
488 if (regnum == -1 || regnum == i)
489 regcache_raw_supply (regcache, i, NULL);
490 if (regnum == -1 || regnum == I387_MXCSR_REGNUM (tdep))
491 {
492 gdb_byte buf[4];
493
494 store_unsigned_integer (buf, 4, byte_order, 0x1f80);
495 regcache_raw_supply (regcache, I387_MXCSR_REGNUM (tdep), buf);
496 }
497 }
498
499 /* Fill register REGNUM (if it is a floating-point register) in *FSAVE
500 with the value from REGCACHE. If REGNUM is -1, do this for all
501 registers. This function doesn't touch any of the reserved bits in
502 *FSAVE. */
503
504 void
505 i387_collect_fsave (const struct regcache *regcache, int regnum, void *fsave)
506 {
507 struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
508 gdb_byte *regs = fsave;
509 int i;
510
511 gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM);
512
513 for (i = I387_ST0_REGNUM (tdep); i < I387_XMM0_REGNUM (tdep); i++)
514 if (regnum == -1 || regnum == i)
515 {
516 /* Most of the FPU control registers occupy only 16 bits in
517 the fsave area. Give those a special treatment. */
518 if (i >= I387_FCTRL_REGNUM (tdep)
519 && i != I387_FIOFF_REGNUM (tdep) && i != I387_FOOFF_REGNUM (tdep))
520 {
521 gdb_byte buf[4];
522
523 regcache_raw_collect (regcache, i, buf);
524
525 if (i == I387_FOP_REGNUM (tdep))
526 {
527 /* The opcode occupies only 11 bits. Make sure we
528 don't touch the other bits. */
529 buf[1] &= ((1 << 3) - 1);
530 buf[1] |= ((FSAVE_ADDR (tdep, regs, i))[1] & ~((1 << 3) - 1));
531 }
532 memcpy (FSAVE_ADDR (tdep, regs, i), buf, 2);
533 }
534 else
535 regcache_raw_collect (regcache, i, FSAVE_ADDR (tdep, regs, i));
536 }
537 }
538 \f
539
540 /* At fxsave_offset[REGNUM] you'll find the offset to the location in
541 the data structure used by the "fxsave" instruction where GDB
542 register REGNUM is stored. */
543
544 static int fxsave_offset[] =
545 {
546 32, /* %st(0) through ... */
547 48,
548 64,
549 80,
550 96,
551 112,
552 128,
553 144, /* ... %st(7) (80 bits each). */
554 0, /* `fctrl' (16 bits). */
555 2, /* `fstat' (16 bits). */
556 4, /* `ftag' (16 bits). */
557 12, /* `fiseg' (16 bits). */
558 8, /* `fioff'. */
559 20, /* `foseg' (16 bits). */
560 16, /* `fooff'. */
561 6, /* `fop' (bottom 11 bits). */
562 160 + 0 * 16, /* %xmm0 through ... */
563 160 + 1 * 16,
564 160 + 2 * 16,
565 160 + 3 * 16,
566 160 + 4 * 16,
567 160 + 5 * 16,
568 160 + 6 * 16,
569 160 + 7 * 16,
570 160 + 8 * 16,
571 160 + 9 * 16,
572 160 + 10 * 16,
573 160 + 11 * 16,
574 160 + 12 * 16,
575 160 + 13 * 16,
576 160 + 14 * 16,
577 160 + 15 * 16, /* ... %xmm15 (128 bits each). */
578 };
579
580 #define FXSAVE_ADDR(tdep, fxsave, regnum) \
581 (fxsave + fxsave_offset[regnum - I387_ST0_REGNUM (tdep)])
582
583 /* We made an unfortunate choice in putting %mxcsr after the SSE
584 registers %xmm0-%xmm7 instead of before, since it makes supporting
585 the registers %xmm8-%xmm15 on AMD64 a bit involved. Therefore we
586 don't include the offset for %mxcsr here above. */
587
588 #define FXSAVE_MXCSR_ADDR(fxsave) (fxsave + 24)
589
590 static int i387_tag (const gdb_byte *raw);
591 \f
592
593 /* Fill register REGNUM in REGCACHE with the appropriate
594 floating-point or SSE register value from *FXSAVE. This function
595 masks off any of the reserved bits in *FXSAVE. */
596
597 void
598 i387_supply_fxsave (struct regcache *regcache, int regnum, const void *fxsave)
599 {
600 struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
601 const gdb_byte *regs = fxsave;
602 int i;
603
604 gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM);
605 gdb_assert (tdep->num_xmm_regs > 0);
606
607 for (i = I387_ST0_REGNUM (tdep); i < I387_MXCSR_REGNUM (tdep); i++)
608 if (regnum == -1 || regnum == i)
609 {
610 if (regs == NULL)
611 {
612 regcache_raw_supply (regcache, i, NULL);
613 continue;
614 }
615
616 /* Most of the FPU control registers occupy only 16 bits in
617 the fxsave area. Give those a special treatment. */
618 if (i >= I387_FCTRL_REGNUM (tdep) && i < I387_XMM0_REGNUM (tdep)
619 && i != I387_FIOFF_REGNUM (tdep) && i != I387_FOOFF_REGNUM (tdep))
620 {
621 gdb_byte val[4];
622
623 memcpy (val, FXSAVE_ADDR (tdep, regs, i), 2);
624 val[2] = val[3] = 0;
625 if (i == I387_FOP_REGNUM (tdep))
626 val[1] &= ((1 << 3) - 1);
627 else if (i== I387_FTAG_REGNUM (tdep))
628 {
629 /* The fxsave area contains a simplified version of
630 the tag word. We have to look at the actual 80-bit
631 FP data to recreate the traditional i387 tag word. */
632
633 unsigned long ftag = 0;
634 int fpreg;
635 int top;
636
637 top = ((FXSAVE_ADDR (tdep, regs,
638 I387_FSTAT_REGNUM (tdep)))[1] >> 3);
639 top &= 0x7;
640
641 for (fpreg = 7; fpreg >= 0; fpreg--)
642 {
643 int tag;
644
645 if (val[0] & (1 << fpreg))
646 {
647 int thisreg = (fpreg + 8 - top) % 8
648 + I387_ST0_REGNUM (tdep);
649 tag = i387_tag (FXSAVE_ADDR (tdep, regs, thisreg));
650 }
651 else
652 tag = 3; /* Empty */
653
654 ftag |= tag << (2 * fpreg);
655 }
656 val[0] = ftag & 0xff;
657 val[1] = (ftag >> 8) & 0xff;
658 }
659 regcache_raw_supply (regcache, i, val);
660 }
661 else
662 regcache_raw_supply (regcache, i, FXSAVE_ADDR (tdep, regs, i));
663 }
664
665 if (regnum == I387_MXCSR_REGNUM (tdep) || regnum == -1)
666 {
667 if (regs == NULL)
668 regcache_raw_supply (regcache, I387_MXCSR_REGNUM (tdep), NULL);
669 else
670 regcache_raw_supply (regcache, I387_MXCSR_REGNUM (tdep),
671 FXSAVE_MXCSR_ADDR (regs));
672 }
673 }
674
675 /* Fill register REGNUM (if it is a floating-point or SSE register) in
676 *FXSAVE with the value from REGCACHE. If REGNUM is -1, do this for
677 all registers. This function doesn't touch any of the reserved
678 bits in *FXSAVE. */
679
680 void
681 i387_collect_fxsave (const struct regcache *regcache, int regnum, void *fxsave)
682 {
683 struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
684 gdb_byte *regs = fxsave;
685 int i;
686
687 gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM);
688 gdb_assert (tdep->num_xmm_regs > 0);
689
690 for (i = I387_ST0_REGNUM (tdep); i < I387_MXCSR_REGNUM (tdep); i++)
691 if (regnum == -1 || regnum == i)
692 {
693 /* Most of the FPU control registers occupy only 16 bits in
694 the fxsave area. Give those a special treatment. */
695 if (i >= I387_FCTRL_REGNUM (tdep) && i < I387_XMM0_REGNUM (tdep)
696 && i != I387_FIOFF_REGNUM (tdep) && i != I387_FOOFF_REGNUM (tdep))
697 {
698 gdb_byte buf[4];
699
700 regcache_raw_collect (regcache, i, buf);
701
702 if (i == I387_FOP_REGNUM (tdep))
703 {
704 /* The opcode occupies only 11 bits. Make sure we
705 don't touch the other bits. */
706 buf[1] &= ((1 << 3) - 1);
707 buf[1] |= ((FXSAVE_ADDR (tdep, regs, i))[1] & ~((1 << 3) - 1));
708 }
709 else if (i == I387_FTAG_REGNUM (tdep))
710 {
711 /* Converting back is much easier. */
712
713 unsigned short ftag;
714 int fpreg;
715
716 ftag = (buf[1] << 8) | buf[0];
717 buf[0] = 0;
718 buf[1] = 0;
719
720 for (fpreg = 7; fpreg >= 0; fpreg--)
721 {
722 int tag = (ftag >> (fpreg * 2)) & 3;
723
724 if (tag != 3)
725 buf[0] |= (1 << fpreg);
726 }
727 }
728 memcpy (FXSAVE_ADDR (tdep, regs, i), buf, 2);
729 }
730 else
731 regcache_raw_collect (regcache, i, FXSAVE_ADDR (tdep, regs, i));
732 }
733
734 if (regnum == I387_MXCSR_REGNUM (tdep) || regnum == -1)
735 regcache_raw_collect (regcache, I387_MXCSR_REGNUM (tdep),
736 FXSAVE_MXCSR_ADDR (regs));
737 }
738
739 /* `xstate_bv' is at byte offset 512. */
740 #define XSAVE_XSTATE_BV_ADDR(xsave) (xsave + 512)
741
742 /* At xsave_avxh_offset[REGNUM] you'll find the offset to the location in
743 the upper 128bit of AVX register data structure used by the "xsave"
744 instruction where GDB register REGNUM is stored. */
745
746 static int xsave_avxh_offset[] =
747 {
748 576 + 0 * 16, /* Upper 128bit of %ymm0 through ... */
749 576 + 1 * 16,
750 576 + 2 * 16,
751 576 + 3 * 16,
752 576 + 4 * 16,
753 576 + 5 * 16,
754 576 + 6 * 16,
755 576 + 7 * 16,
756 576 + 8 * 16,
757 576 + 9 * 16,
758 576 + 10 * 16,
759 576 + 11 * 16,
760 576 + 12 * 16,
761 576 + 13 * 16,
762 576 + 14 * 16,
763 576 + 15 * 16 /* Upper 128bit of ... %ymm15 (128 bits each). */
764 };
765
766 static int xsave_mpx_offset[] =
767 {
768 960 + 0 * 16, /* bnd0r...bnd3r registers. */
769 960 + 1 * 16,
770 960 + 2 * 16,
771 960 + 3 * 16,
772 1024 + 0 * 8, /* bndcfg ... bndstatus. */
773 1024 + 1 * 8,
774 };
775
776 #define XSAVE_AVXH_ADDR(tdep, xsave, regnum) \
777 (xsave + xsave_avxh_offset[regnum - I387_YMM0H_REGNUM (tdep)])
778
779 #define XSAVE_MPX_ADDR(tdep, xsave, regnum) \
780 (xsave + xsave_mpx_offset[regnum - I387_BND0R_REGNUM (tdep)])
781
782 /* Similar to i387_supply_fxsave, but use XSAVE extended state. */
783
784 void
785 i387_supply_xsave (struct regcache *regcache, int regnum,
786 const void *xsave)
787 {
788 struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
789 const gdb_byte *regs = xsave;
790 int i;
791 unsigned int clear_bv;
792 static const gdb_byte zero[MAX_REGISTER_SIZE] = { 0 };
793 enum
794 {
795 none = 0x0,
796 x87 = 0x1,
797 sse = 0x2,
798 avxh = 0x4,
799 mpx = 0x8,
800 all = x87 | sse | avxh | mpx
801 } regclass;
802
803 gdb_assert (regs != NULL);
804 gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM);
805 gdb_assert (tdep->num_xmm_regs > 0);
806
807 if (regnum == -1)
808 regclass = all;
809 else if (regnum >= I387_YMM0H_REGNUM (tdep)
810 && regnum < I387_YMMENDH_REGNUM (tdep))
811 regclass = avxh;
812 else if (regnum >= I387_BND0R_REGNUM (tdep)
813 && regnum < I387_MPXEND_REGNUM (tdep))
814 regclass = mpx;
815 else if (regnum >= I387_XMM0_REGNUM(tdep)
816 && regnum < I387_MXCSR_REGNUM (tdep))
817 regclass = sse;
818 else if (regnum >= I387_ST0_REGNUM (tdep)
819 && regnum < I387_FCTRL_REGNUM (tdep))
820 regclass = x87;
821 else
822 regclass = none;
823
824 if (regclass != none)
825 {
826 /* Get `xstat_bv'. */
827 const gdb_byte *xstate_bv_p = XSAVE_XSTATE_BV_ADDR (regs);
828
829 /* The supported bits in `xstat_bv' are 1 byte. Clear part in
830 vector registers if its bit in xstat_bv is zero. */
831 clear_bv = (~(*xstate_bv_p)) & tdep->xcr0;
832 }
833 else
834 clear_bv = I386_XSTATE_ALL_MASK;
835
836 /* With the delayed xsave mechanism, in between the program
837 starting, and the program accessing the vector registers for the
838 first time, the register's values are invalid. The kernel
839 initializes register states to zero when they are set the first
840 time in a program. This means that from the user-space programs'
841 perspective, it's the same as if the registers have always been
842 zero from the start of the program. Therefore, the debugger
843 should provide the same illusion to the user. */
844
845 switch (regclass)
846 {
847 case none:
848 break;
849
850 case avxh:
851 if ((clear_bv & I386_XSTATE_AVX))
852 regcache_raw_supply (regcache, regnum, zero);
853 else
854 regcache_raw_supply (regcache, regnum,
855 XSAVE_AVXH_ADDR (tdep, regs, regnum));
856 return;
857
858 case mpx:
859 if ((clear_bv & I386_XSTATE_BNDREGS))
860 regcache_raw_supply (regcache, regnum, zero);
861 else
862 regcache_raw_supply (regcache, regnum,
863 XSAVE_MPX_ADDR (tdep, regs, regnum));
864 return;
865
866 case sse:
867 if ((clear_bv & I386_XSTATE_SSE))
868 regcache_raw_supply (regcache, regnum, zero);
869 else
870 regcache_raw_supply (regcache, regnum,
871 FXSAVE_ADDR (tdep, regs, regnum));
872 return;
873
874 case x87:
875 if ((clear_bv & I386_XSTATE_X87))
876 regcache_raw_supply (regcache, regnum, zero);
877 else
878 regcache_raw_supply (regcache, regnum,
879 FXSAVE_ADDR (tdep, regs, regnum));
880 return;
881
882 case all:
883 /* Handle the upper YMM registers. */
884 if ((tdep->xcr0 & I386_XSTATE_AVX))
885 {
886 if ((clear_bv & I386_XSTATE_AVX))
887 {
888 for (i = I387_YMM0H_REGNUM (tdep);
889 i < I387_YMMENDH_REGNUM (tdep);
890 i++)
891 regcache_raw_supply (regcache, i, zero);
892 }
893 else
894 {
895 for (i = I387_YMM0H_REGNUM (tdep);
896 i < I387_YMMENDH_REGNUM (tdep);
897 i++)
898 regcache_raw_supply (regcache, i,
899 XSAVE_AVXH_ADDR (tdep, regs, i));
900 }
901 }
902
903 /* Handle the MPX registers. */
904 if ((tdep->xcr0 & I386_XSTATE_BNDREGS))
905 {
906 if (clear_bv & I386_XSTATE_BNDREGS)
907 {
908 for (i = I387_BND0R_REGNUM (tdep);
909 i < I387_BNDCFGU_REGNUM (tdep); i++)
910 regcache_raw_supply (regcache, i, zero);
911 }
912 else
913 {
914 for (i = I387_BND0R_REGNUM (tdep);
915 i < I387_BNDCFGU_REGNUM (tdep); i++)
916 regcache_raw_supply (regcache, i,
917 XSAVE_MPX_ADDR (tdep, regs, i));
918 }
919 }
920
921 /* Handle the MPX registers. */
922 if ((tdep->xcr0 & I386_XSTATE_BNDCFG))
923 {
924 if (clear_bv & I386_XSTATE_BNDCFG)
925 {
926 for (i = I387_BNDCFGU_REGNUM (tdep);
927 i < I387_MPXEND_REGNUM (tdep); i++)
928 regcache_raw_supply (regcache, i, zero);
929 }
930 else
931 {
932 for (i = I387_BNDCFGU_REGNUM (tdep);
933 i < I387_MPXEND_REGNUM (tdep); i++)
934 regcache_raw_supply (regcache, i,
935 XSAVE_MPX_ADDR (tdep, regs, i));
936 }
937 }
938
939 /* Handle the XMM registers. */
940 if ((tdep->xcr0 & I386_XSTATE_SSE))
941 {
942 if ((clear_bv & I386_XSTATE_SSE))
943 {
944 for (i = I387_XMM0_REGNUM (tdep);
945 i < I387_MXCSR_REGNUM (tdep);
946 i++)
947 regcache_raw_supply (regcache, i, zero);
948 }
949 else
950 {
951 for (i = I387_XMM0_REGNUM (tdep);
952 i < I387_MXCSR_REGNUM (tdep); i++)
953 regcache_raw_supply (regcache, i,
954 FXSAVE_ADDR (tdep, regs, i));
955 }
956 }
957
958 /* Handle the x87 registers. */
959 if ((tdep->xcr0 & I386_XSTATE_X87))
960 {
961 if ((clear_bv & I386_XSTATE_X87))
962 {
963 for (i = I387_ST0_REGNUM (tdep);
964 i < I387_FCTRL_REGNUM (tdep);
965 i++)
966 regcache_raw_supply (regcache, i, zero);
967 }
968 else
969 {
970 for (i = I387_ST0_REGNUM (tdep);
971 i < I387_FCTRL_REGNUM (tdep);
972 i++)
973 regcache_raw_supply (regcache, i, FXSAVE_ADDR (tdep, regs, i));
974 }
975 }
976 break;
977 }
978
979 /* Only handle x87 control registers. */
980 for (i = I387_FCTRL_REGNUM (tdep); i < I387_XMM0_REGNUM (tdep); i++)
981 if (regnum == -1 || regnum == i)
982 {
983 /* Most of the FPU control registers occupy only 16 bits in
984 the xsave extended state. Give those a special treatment. */
985 if (i != I387_FIOFF_REGNUM (tdep)
986 && i != I387_FOOFF_REGNUM (tdep))
987 {
988 gdb_byte val[4];
989
990 memcpy (val, FXSAVE_ADDR (tdep, regs, i), 2);
991 val[2] = val[3] = 0;
992 if (i == I387_FOP_REGNUM (tdep))
993 val[1] &= ((1 << 3) - 1);
994 else if (i== I387_FTAG_REGNUM (tdep))
995 {
996 /* The fxsave area contains a simplified version of
997 the tag word. We have to look at the actual 80-bit
998 FP data to recreate the traditional i387 tag word. */
999
1000 unsigned long ftag = 0;
1001 int fpreg;
1002 int top;
1003
1004 top = ((FXSAVE_ADDR (tdep, regs,
1005 I387_FSTAT_REGNUM (tdep)))[1] >> 3);
1006 top &= 0x7;
1007
1008 for (fpreg = 7; fpreg >= 0; fpreg--)
1009 {
1010 int tag;
1011
1012 if (val[0] & (1 << fpreg))
1013 {
1014 int thisreg = (fpreg + 8 - top) % 8
1015 + I387_ST0_REGNUM (tdep);
1016 tag = i387_tag (FXSAVE_ADDR (tdep, regs, thisreg));
1017 }
1018 else
1019 tag = 3; /* Empty */
1020
1021 ftag |= tag << (2 * fpreg);
1022 }
1023 val[0] = ftag & 0xff;
1024 val[1] = (ftag >> 8) & 0xff;
1025 }
1026 regcache_raw_supply (regcache, i, val);
1027 }
1028 else
1029 regcache_raw_supply (regcache, i, FXSAVE_ADDR (tdep, regs, i));
1030 }
1031
1032 if (regnum == I387_MXCSR_REGNUM (tdep) || regnum == -1)
1033 regcache_raw_supply (regcache, I387_MXCSR_REGNUM (tdep),
1034 FXSAVE_MXCSR_ADDR (regs));
1035 }
1036
1037 /* Similar to i387_collect_fxsave, but use XSAVE extended state. */
1038
1039 void
1040 i387_collect_xsave (const struct regcache *regcache, int regnum,
1041 void *xsave, int gcore)
1042 {
1043 struct gdbarch_tdep *tdep = gdbarch_tdep (get_regcache_arch (regcache));
1044 gdb_byte *regs = xsave;
1045 int i;
1046 enum
1047 {
1048 none = 0x0,
1049 check = 0x1,
1050 x87 = 0x2 | check,
1051 sse = 0x4 | check,
1052 avxh = 0x8 | check,
1053 mpx = 0x10 | check,
1054 all = x87 | sse | avxh | mpx
1055 } regclass;
1056
1057 gdb_assert (tdep->st0_regnum >= I386_ST0_REGNUM);
1058 gdb_assert (tdep->num_xmm_regs > 0);
1059
1060 if (regnum == -1)
1061 regclass = all;
1062 else if (regnum >= I387_YMM0H_REGNUM (tdep)
1063 && regnum < I387_YMMENDH_REGNUM (tdep))
1064 regclass = avxh;
1065 else if (regnum >= I387_BND0R_REGNUM (tdep)
1066 && regnum < I387_MPXEND_REGNUM (tdep))
1067 regclass = mpx;
1068 else if (regnum >= I387_XMM0_REGNUM (tdep)
1069 && regnum < I387_MXCSR_REGNUM (tdep))
1070 regclass = sse;
1071 else if (regnum >= I387_ST0_REGNUM (tdep)
1072 && regnum < I387_FCTRL_REGNUM (tdep))
1073 regclass = x87;
1074 else
1075 regclass = none;
1076
1077 if (gcore)
1078 {
1079 /* Clear XSAVE extended state. */
1080 memset (regs, 0, I386_XSTATE_SIZE (tdep->xcr0));
1081
1082 /* Update XCR0 and `xstate_bv' with XCR0 for gcore. */
1083 if (tdep->xsave_xcr0_offset != -1)
1084 memcpy (regs + tdep->xsave_xcr0_offset, &tdep->xcr0, 8);
1085 memcpy (XSAVE_XSTATE_BV_ADDR (regs), &tdep->xcr0, 8);
1086 }
1087
1088 if ((regclass & check))
1089 {
1090 gdb_byte raw[I386_MAX_REGISTER_SIZE];
1091 gdb_byte *xstate_bv_p = XSAVE_XSTATE_BV_ADDR (regs);
1092 unsigned int xstate_bv = 0;
1093 /* The supported bits in `xstat_bv' are 1 byte. */
1094 unsigned int clear_bv = (~(*xstate_bv_p)) & tdep->xcr0;
1095 gdb_byte *p;
1096
1097 /* Clear register set if its bit in xstat_bv is zero. */
1098 if (clear_bv)
1099 {
1100 if ((clear_bv & I386_XSTATE_BNDREGS))
1101 for (i = I387_BND0R_REGNUM (tdep);
1102 i < I387_BNDCFGU_REGNUM (tdep); i++)
1103 memset (XSAVE_MPX_ADDR (tdep, regs, i), 0, 16);
1104
1105 if ((clear_bv & I386_XSTATE_BNDCFG))
1106 for (i = I387_BNDCFGU_REGNUM (tdep);
1107 i < I387_MPXEND_REGNUM (tdep); i++)
1108 memset (XSAVE_MPX_ADDR (tdep, regs, i), 0, 8);
1109
1110 if ((clear_bv & I386_XSTATE_AVX))
1111 for (i = I387_YMM0H_REGNUM (tdep);
1112 i < I387_YMMENDH_REGNUM (tdep); i++)
1113 memset (XSAVE_AVXH_ADDR (tdep, regs, i), 0, 16);
1114
1115 if ((clear_bv & I386_XSTATE_SSE))
1116 for (i = I387_XMM0_REGNUM (tdep);
1117 i < I387_MXCSR_REGNUM (tdep); i++)
1118 memset (FXSAVE_ADDR (tdep, regs, i), 0, 16);
1119
1120 if ((clear_bv & I386_XSTATE_X87))
1121 for (i = I387_ST0_REGNUM (tdep);
1122 i < I387_FCTRL_REGNUM (tdep); i++)
1123 memset (FXSAVE_ADDR (tdep, regs, i), 0, 10);
1124 }
1125
1126 if (regclass == all)
1127 {
1128 /* Check if any upper YMM registers are changed. */
1129 if ((tdep->xcr0 & I386_XSTATE_AVX))
1130 for (i = I387_YMM0H_REGNUM (tdep);
1131 i < I387_YMMENDH_REGNUM (tdep); i++)
1132 {
1133 regcache_raw_collect (regcache, i, raw);
1134 p = XSAVE_AVXH_ADDR (tdep, regs, i);
1135 if (memcmp (raw, p, 16))
1136 {
1137 xstate_bv |= I386_XSTATE_AVX;
1138 memcpy (p, raw, 16);
1139 }
1140 }
1141 /* Check if any upper MPX registers are changed. */
1142 if ((tdep->xcr0 & I386_XSTATE_BNDREGS))
1143 for (i = I387_BND0R_REGNUM (tdep);
1144 i < I387_BNDCFGU_REGNUM (tdep); i++)
1145 {
1146 regcache_raw_collect (regcache, i, raw);
1147 p = XSAVE_MPX_ADDR (tdep, regs, i);
1148 if (memcmp (raw, p, 16))
1149 {
1150 xstate_bv |= I386_XSTATE_BNDREGS;
1151 memcpy (p, raw, 16);
1152 }
1153 }
1154
1155 /* Check if any upper MPX registers are changed. */
1156 if ((tdep->xcr0 & I386_XSTATE_BNDCFG))
1157 for (i = I387_BNDCFGU_REGNUM (tdep);
1158 i < I387_MPXEND_REGNUM (tdep); i++)
1159 {
1160 regcache_raw_collect (regcache, i, raw);
1161 p = XSAVE_MPX_ADDR (tdep, regs, i);
1162 if (memcmp (raw, p, 8))
1163 {
1164 xstate_bv |= I386_XSTATE_BNDCFG;
1165 memcpy (p, raw, 8);
1166 }
1167 }
1168
1169 /* Check if any SSE registers are changed. */
1170 if ((tdep->xcr0 & I386_XSTATE_SSE))
1171 for (i = I387_XMM0_REGNUM (tdep);
1172 i < I387_MXCSR_REGNUM (tdep); i++)
1173 {
1174 regcache_raw_collect (regcache, i, raw);
1175 p = FXSAVE_ADDR (tdep, regs, i);
1176 if (memcmp (raw, p, 16))
1177 {
1178 xstate_bv |= I386_XSTATE_SSE;
1179 memcpy (p, raw, 16);
1180 }
1181 }
1182
1183 /* Check if any X87 registers are changed. */
1184 if ((tdep->xcr0 & I386_XSTATE_X87))
1185 for (i = I387_ST0_REGNUM (tdep);
1186 i < I387_FCTRL_REGNUM (tdep); i++)
1187 {
1188 regcache_raw_collect (regcache, i, raw);
1189 p = FXSAVE_ADDR (tdep, regs, i);
1190 if (memcmp (raw, p, 10))
1191 {
1192 xstate_bv |= I386_XSTATE_X87;
1193 memcpy (p, raw, 10);
1194 }
1195 }
1196 }
1197 else
1198 {
1199 /* Check if REGNUM is changed. */
1200 regcache_raw_collect (regcache, regnum, raw);
1201
1202 switch (regclass)
1203 {
1204 default:
1205 internal_error (__FILE__, __LINE__,
1206 _("invalid i387 regclass"));
1207
1208 case avxh:
1209 /* This is an upper YMM register. */
1210 p = XSAVE_AVXH_ADDR (tdep, regs, regnum);
1211 if (memcmp (raw, p, 16))
1212 {
1213 xstate_bv |= I386_XSTATE_AVX;
1214 memcpy (p, raw, 16);
1215 }
1216 break;
1217
1218 case mpx:
1219 if (regnum < I387_BNDCFGU_REGNUM (tdep))
1220 {
1221 regcache_raw_collect (regcache, regnum, raw);
1222 p = XSAVE_MPX_ADDR (tdep, regs, regnum);
1223 if (memcmp (raw, p, 16))
1224 {
1225 xstate_bv |= I386_XSTATE_BNDREGS;
1226 memcpy (p, raw, 16);
1227 }
1228 }
1229 else
1230 {
1231 p = XSAVE_MPX_ADDR (tdep, regs, regnum);
1232 xstate_bv |= I386_XSTATE_BNDCFG;
1233 memcpy (p, raw, 8);
1234 }
1235 break;
1236
1237 case sse:
1238 /* This is an SSE register. */
1239 p = FXSAVE_ADDR (tdep, regs, regnum);
1240 if (memcmp (raw, p, 16))
1241 {
1242 xstate_bv |= I386_XSTATE_SSE;
1243 memcpy (p, raw, 16);
1244 }
1245 break;
1246
1247 case x87:
1248 /* This is an x87 register. */
1249 p = FXSAVE_ADDR (tdep, regs, regnum);
1250 if (memcmp (raw, p, 10))
1251 {
1252 xstate_bv |= I386_XSTATE_X87;
1253 memcpy (p, raw, 10);
1254 }
1255 break;
1256 }
1257 }
1258
1259 /* Update the corresponding bits in `xstate_bv' if any SSE/AVX
1260 registers are changed. */
1261 if (xstate_bv)
1262 {
1263 /* The supported bits in `xstat_bv' are 1 byte. */
1264 *xstate_bv_p |= (gdb_byte) xstate_bv;
1265
1266 switch (regclass)
1267 {
1268 default:
1269 internal_error (__FILE__, __LINE__,
1270 _("invalid i387 regclass"));
1271
1272 case all:
1273 break;
1274
1275 case x87:
1276 case sse:
1277 case avxh:
1278 case mpx:
1279 /* Register REGNUM has been updated. Return. */
1280 return;
1281 }
1282 }
1283 else
1284 {
1285 /* Return if REGNUM isn't changed. */
1286 if (regclass != all)
1287 return;
1288 }
1289 }
1290
1291 /* Only handle x87 control registers. */
1292 for (i = I387_FCTRL_REGNUM (tdep); i < I387_XMM0_REGNUM (tdep); i++)
1293 if (regnum == -1 || regnum == i)
1294 {
1295 /* Most of the FPU control registers occupy only 16 bits in
1296 the xsave extended state. Give those a special treatment. */
1297 if (i != I387_FIOFF_REGNUM (tdep)
1298 && i != I387_FOOFF_REGNUM (tdep))
1299 {
1300 gdb_byte buf[4];
1301
1302 regcache_raw_collect (regcache, i, buf);
1303
1304 if (i == I387_FOP_REGNUM (tdep))
1305 {
1306 /* The opcode occupies only 11 bits. Make sure we
1307 don't touch the other bits. */
1308 buf[1] &= ((1 << 3) - 1);
1309 buf[1] |= ((FXSAVE_ADDR (tdep, regs, i))[1] & ~((1 << 3) - 1));
1310 }
1311 else if (i == I387_FTAG_REGNUM (tdep))
1312 {
1313 /* Converting back is much easier. */
1314
1315 unsigned short ftag;
1316 int fpreg;
1317
1318 ftag = (buf[1] << 8) | buf[0];
1319 buf[0] = 0;
1320 buf[1] = 0;
1321
1322 for (fpreg = 7; fpreg >= 0; fpreg--)
1323 {
1324 int tag = (ftag >> (fpreg * 2)) & 3;
1325
1326 if (tag != 3)
1327 buf[0] |= (1 << fpreg);
1328 }
1329 }
1330 memcpy (FXSAVE_ADDR (tdep, regs, i), buf, 2);
1331 }
1332 else
1333 regcache_raw_collect (regcache, i, FXSAVE_ADDR (tdep, regs, i));
1334 }
1335
1336 if (regnum == I387_MXCSR_REGNUM (tdep) || regnum == -1)
1337 regcache_raw_collect (regcache, I387_MXCSR_REGNUM (tdep),
1338 FXSAVE_MXCSR_ADDR (regs));
1339 }
1340
1341 /* Recreate the FTW (tag word) valid bits from the 80-bit FP data in
1342 *RAW. */
1343
1344 static int
1345 i387_tag (const gdb_byte *raw)
1346 {
1347 int integer;
1348 unsigned int exponent;
1349 unsigned long fraction[2];
1350
1351 integer = raw[7] & 0x80;
1352 exponent = (((raw[9] & 0x7f) << 8) | raw[8]);
1353 fraction[0] = ((raw[3] << 24) | (raw[2] << 16) | (raw[1] << 8) | raw[0]);
1354 fraction[1] = (((raw[7] & 0x7f) << 24) | (raw[6] << 16)
1355 | (raw[5] << 8) | raw[4]);
1356
1357 if (exponent == 0x7fff)
1358 {
1359 /* Special. */
1360 return (2);
1361 }
1362 else if (exponent == 0x0000)
1363 {
1364 if (fraction[0] == 0x0000 && fraction[1] == 0x0000 && !integer)
1365 {
1366 /* Zero. */
1367 return (1);
1368 }
1369 else
1370 {
1371 /* Special. */
1372 return (2);
1373 }
1374 }
1375 else
1376 {
1377 if (integer)
1378 {
1379 /* Valid. */
1380 return (0);
1381 }
1382 else
1383 {
1384 /* Special. */
1385 return (2);
1386 }
1387 }
1388 }
1389
1390 /* Prepare the FPU stack in REGCACHE for a function return. */
1391
1392 void
1393 i387_return_value (struct gdbarch *gdbarch, struct regcache *regcache)
1394 {
1395 struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
1396 ULONGEST fstat;
1397
1398 /* Set the top of the floating-point register stack to 7. The
1399 actual value doesn't really matter, but 7 is what a normal
1400 function return would end up with if the program started out with
1401 a freshly initialized FPU. */
1402 regcache_raw_read_unsigned (regcache, I387_FSTAT_REGNUM (tdep), &fstat);
1403 fstat |= (7 << 11);
1404 regcache_raw_write_unsigned (regcache, I387_FSTAT_REGNUM (tdep), fstat);
1405
1406 /* Mark %st(1) through %st(7) as empty. Since we set the top of the
1407 floating-point register stack to 7, the appropriate value for the
1408 tag word is 0x3fff. */
1409 regcache_raw_write_unsigned (regcache, I387_FTAG_REGNUM (tdep), 0x3fff);
1410
1411 }
This page took 0.089634 seconds and 4 git commands to generate.