mono/mini/exceptions-amd64.c

   1 /*
   2  * exceptions-amd64.c: exception support for AMD64
   3  *
   4  * Authors:
   5  *   Dietmar Maurer (dietmar@ximian.com)
   6  *
   7  * (C) 2001 Ximian, Inc.
   8  */
   9
  10 #include <config.h>
  11 #include <glib.h>
  12 #include <signal.h>
  13 #include <string.h>
  14 #include <sys/ucontext.h>
  15
  16 #include <mono/arch/amd64/amd64-codegen.h>
  17 #include <mono/metadata/appdomain.h>
  18 #include <mono/metadata/tabledefs.h>
  19 #include <mono/metadata/threads.h>
  20 #include <mono/metadata/debug-helpers.h>
  21 #include <mono/metadata/exception.h>
  22 #include <mono/metadata/gc-internal.h>
  23 #include <mono/metadata/mono-debug.h>
  24
  25 #include "mini.h"
  26 #include "mini-amd64.h"
  27
  28 #define ALIGN_TO(val,align) (((val) + ((align) - 1)) & ~((align) - 1))
  29
  30 #ifdef PLATFORM_WIN32
  31 static MonoW32ExceptionHandler fpe_handler;
  32 static MonoW32ExceptionHandler ill_handler;
  33 static MonoW32ExceptionHandler segv_handler;
  34
  35 static LPTOP_LEVEL_EXCEPTION_FILTER old_handler;
  36
  37 #define W32_SEH_HANDLE_EX(_ex) \
  38         if (_ex##_handler) _ex##_handler((int)sctx)
  39
  40 /*
  41  * Unhandled Exception Filter
  42  * Top-level per-process exception handler.
  43  */
  44 LONG CALLBACK seh_handler(EXCEPTION_POINTERS* ep)
  45 {
  46         EXCEPTION_RECORD* er;
  47         CONTEXT* ctx;
  48         MonoContext* sctx;
  49         LONG res;
  50
  51         res = EXCEPTION_CONTINUE_EXECUTION;
  52
  53         er = ep->ExceptionRecord;
  54         ctx = ep->ContextRecord;
  55         sctx = g_malloc(sizeof(MonoContext));
  56
  57         /* Copy Win32 context to UNIX style context */
  58         sctx->eax = ctx->Eax;
  59         sctx->ebx = ctx->Ebx;
  60         sctx->ecx = ctx->Ecx;
  61         sctx->edx = ctx->Edx;
  62         sctx->ebp = ctx->Ebp;
  63         sctx->esp = ctx->Esp;
  64         sctx->esi = ctx->Esi;
  65         sctx->edi = ctx->Edi;
  66         sctx->eip = ctx->Eip;
  67
  68         switch (er->ExceptionCode) {
  69         case EXCEPTION_ACCESS_VIOLATION:
  70                 W32_SEH_HANDLE_EX(segv);
  71                 break;
  72         case EXCEPTION_ILLEGAL_INSTRUCTION:
  73                 W32_SEH_HANDLE_EX(ill);
  74                 break;
  75         case EXCEPTION_INT_DIVIDE_BY_ZERO:
  76         case EXCEPTION_INT_OVERFLOW:
  77         case EXCEPTION_FLT_DIVIDE_BY_ZERO:
  78         case EXCEPTION_FLT_OVERFLOW:
  79         case EXCEPTION_FLT_UNDERFLOW:
  80         case EXCEPTION_FLT_INEXACT_RESULT:
  81                 W32_SEH_HANDLE_EX(fpe);
  82                 break;
  83         default:
  84                 break;
  85         }
  86
  87         /* Copy context back */
  88         ctx->Eax = sctx->eax;
  89         ctx->Ebx = sctx->ebx;
  90         ctx->Ecx = sctx->ecx;
  91         ctx->Edx = sctx->edx;
  92         ctx->Ebp = sctx->ebp;
  93         ctx->Esp = sctx->esp;
  94         ctx->Esi = sctx->esi;
  95         ctx->Edi = sctx->edi;
  96         ctx->Eip = sctx->eip;
  97
  98         return res;
  99 }
 100
 101 void win32_seh_init()
 102 {
 103         old_handler = SetUnhandledExceptionFilter(seh_handler);
 104 }
 105
 106 void win32_seh_cleanup()
 107 {
 108         if (old_handler) SetUnhandledExceptionFilter(old_handler);
 109 }
 110
 111 void win32_seh_set_handler(int type, MonoW32ExceptionHandler handler)
 112 {
 113         switch (type) {
 114         case SIGFPE:
 115                 fpe_handler = handler;
 116                 break;
 117         case SIGILL:
 118                 ill_handler = handler;
 119                 break;
 120         case SIGSEGV:
 121                 segv_handler = handler;
 122                 break;
 123         default:
 124                 break;
 125         }
 126 }
 127
 128 #endif /* PLATFORM_WIN32 */
 129
 130 /*
 131  * mono_arch_get_restore_context:
 132  *
 133  * Returns a pointer to a method which restores a previously saved sigcontext.
 134  */
 135 gpointer
 136 mono_arch_get_restore_context (void)
 137 {
 138         static guint8 *start = NULL;
 139         static gboolean inited = FALSE;
 140         guint8 *code;
 141
 142         if (inited)
 143                 return start;
 144
 145         /* restore_contect (MonoContext *ctx) */
 146
 147         start = code = mono_global_codeman_reserve (256);
 148
 149         /* get return address */
 150         amd64_mov_reg_membase (code, AMD64_RAX, AMD64_RDI,  G_STRUCT_OFFSET (MonoContext, rip), 8);
 151
 152         /* Restore registers */
 153         amd64_mov_reg_membase (code, AMD64_RBP, AMD64_RDI,  G_STRUCT_OFFSET (MonoContext, rbp), 8);
 154         amd64_mov_reg_membase (code, AMD64_RBX, AMD64_RDI,  G_STRUCT_OFFSET (MonoContext, rbx), 8);
 155         amd64_mov_reg_membase (code, AMD64_R12, AMD64_RDI,  G_STRUCT_OFFSET (MonoContext, r12), 8);
 156         amd64_mov_reg_membase (code, AMD64_R13, AMD64_RDI,  G_STRUCT_OFFSET (MonoContext, r13), 8);
 157         amd64_mov_reg_membase (code, AMD64_R14, AMD64_RDI,  G_STRUCT_OFFSET (MonoContext, r14), 8);
 158         amd64_mov_reg_membase (code, AMD64_R15, AMD64_RDI,  G_STRUCT_OFFSET (MonoContext, r15), 8);
 159
 160         amd64_mov_reg_membase (code, AMD64_RSP, AMD64_RDI,  G_STRUCT_OFFSET (MonoContext, rsp), 8);
 161
 162         /* jump to the saved IP */
 163         amd64_jump_reg (code, AMD64_RAX);
 164
 165         inited = TRUE;
 166
 167         return start;
 168 }
 169
 170 /*
 171  * mono_arch_get_call_filter:
 172  *
 173  * Returns a pointer to a method which calls an exception filter. We
 174  * also use this function to call finally handlers (we pass NULL as
 175  * @exc object in this case).
 176  */
 177 gpointer
 178 mono_arch_get_call_filter (void)
 179 {
 180         static guint8 *start;
 181         static gboolean inited = FALSE;
 182         int i;
 183         guint8 *code;
 184         guint32 pos;
 185
 186         if (inited)
 187                 return start;
 188
 189         start = code = mono_global_codeman_reserve (64);
 190
 191         /* call_filter (MonoContext *ctx, unsigned long eip) */
 192         code = start;
 193
 194         /* Alloc new frame */
 195         amd64_push_reg (code, AMD64_RBP);
 196         amd64_mov_reg_reg (code, AMD64_RBP, AMD64_RSP, 8);
 197
 198         /* Save callee saved regs */
 199         pos = 0;
 200         for (i = 0; i < AMD64_NREG; ++i)
 201                 if (AMD64_IS_CALLEE_SAVED_REG (i)) {
 202                         amd64_push_reg (code, i);
 203                         pos += 8;
 204                 }
 205
 206         /* Save EBP */
 207         pos += 8;
 208         amd64_push_reg (code, AMD64_RBP);
 209
 210         /* Make stack misaligned, the call will make it aligned again */
 211         if (! (pos & 8))
 212                 amd64_alu_reg_imm (code, X86_SUB, AMD64_RSP, 8);
 213
 214         /* set new EBP */
 215         amd64_mov_reg_membase (code, AMD64_RBP, AMD64_RDI, G_STRUCT_OFFSET (MonoContext, rbp), 8);
 216         /* load callee saved regs */
 217         amd64_mov_reg_membase (code, AMD64_RBX, AMD64_RDI, G_STRUCT_OFFSET (MonoContext, rbx), 8);
 218         amd64_mov_reg_membase (code, AMD64_R12, AMD64_RDI, G_STRUCT_OFFSET (MonoContext, r12), 8);
 219         amd64_mov_reg_membase (code, AMD64_R13, AMD64_RDI, G_STRUCT_OFFSET (MonoContext, r13), 8);
 220         amd64_mov_reg_membase (code, AMD64_R14, AMD64_RDI, G_STRUCT_OFFSET (MonoContext, r14), 8);
 221         amd64_mov_reg_membase (code, AMD64_R15, AMD64_RDI, G_STRUCT_OFFSET (MonoContext, r15), 8);
 222
 223         /* call the handler */
 224         amd64_call_reg (code, AMD64_RSI);
 225
 226         if (! (pos & 8))
 227                 amd64_alu_reg_imm (code, X86_ADD, AMD64_RSP, 8);
 228
 229         /* restore RBP */
 230         amd64_pop_reg (code, AMD64_RBP);
 231
 232         /* Restore callee saved regs */
 233         for (i = AMD64_NREG; i >= 0; --i)
 234                 if (AMD64_IS_CALLEE_SAVED_REG (i))
 235                         amd64_pop_reg (code, i);
 236
 237         amd64_leave (code);
 238         amd64_ret (code);
 239
 240         g_assert ((code - start) < 64);
 241
 242         inited = TRUE;
 243
 244         return start;
 245 }
 246
 247 static void
 248 throw_exception (MonoObject *exc, guint64 rip, guint64 rsp,
 249                  guint64 rbx, guint64 rbp, guint64 r12, guint64 r13,
 250                  guint64 r14, guint64 r15, guint64 rethrow)
 251 {
 252         static void (*restore_context) (MonoContext *);
 253         MonoContext ctx;
 254
 255         if (!restore_context)
 256                 restore_context = mono_arch_get_restore_context ();
 257
 258         ctx.rsp = rsp;
 259         ctx.rip = rip;
 260         ctx.rbx = rbx;
 261         ctx.rbp = rbp;
 262         ctx.r12 = r12;
 263         ctx.r13 = r13;
 264         ctx.r14 = r14;
 265         ctx.r15 = r15;
 266
 267         if (!rethrow && mono_debugger_throw_exception ((gpointer)(rip - 8), (gpointer)rsp, exc)) {
 268                 /*
 269                  * The debugger wants us to stop on the `throw' instruction.
 270                  * By the time we get here, it already inserted a breakpoint on
 271                  * eip - 8 (which is the address of the `mov %r15,%rdi ; callq throw').
 272                  */
 273
 274                 /* FIXME FIXME
 275                  *
 276                  * In case of a rethrow, the JIT is emitting code like this:
 277                  *
 278                  *    mov    0xffffffffffffffd0(%rbp),%rax'
 279                  *    mov    %rax,%rdi
 280                  *    callq  throw
 281                  *
 282                  * Here, restore_context() wouldn't restore the %rax register correctly.
 283                  */
 284                 ctx.rip = rip - 8;
 285                 ctx.rsp = rsp + 8;
 286                 restore_context (&ctx);
 287                 g_assert_not_reached ();
 288         }
 289
 290         /* adjust eip so that it point into the call instruction */
 291         ctx.rip -= 1;
 292
 293         if (mono_object_isinst (exc, mono_defaults.exception_class)) {
 294                 MonoException *mono_ex = (MonoException*)exc;
 295                 if (!rethrow)
 296                         mono_ex->stack_trace = NULL;
 297         }
 298         mono_handle_exception (&ctx, exc, (gpointer)rip, FALSE);
 299         restore_context (&ctx);
 300
 301         g_assert_not_reached ();
 302 }
 303
 304 static gpointer
 305 get_throw_trampoline (gboolean rethrow)
 306 {
 307         guint8* start;
 308         guint8 *code;
 309
 310         start = code = mono_global_codeman_reserve (64);
 311
 312         code = start;
 313
 314         /* Exception */
 315         amd64_mov_reg_reg (code, AMD64_RDI, AMD64_RDI, 8);
 316         /* IP */
 317         amd64_mov_reg_membase (code, AMD64_RSI, AMD64_RSP, 0, 8);
 318         /* SP */
 319         amd64_lea_membase (code, AMD64_RDX, AMD64_RSP, 8);
 320         /* Callee saved regs */
 321         amd64_mov_reg_reg (code, AMD64_RCX, AMD64_RBX, 8);
 322         amd64_mov_reg_reg (code, AMD64_R8, AMD64_RBP, 8);
 323         amd64_mov_reg_reg (code, AMD64_R9, AMD64_R12, 8);
 324         /* align stack */
 325         amd64_push_imm (code, 0);
 326         /* reverse order */
 327         amd64_push_imm (code, rethrow);
 328         amd64_push_reg (code, AMD64_R15);
 329         amd64_push_reg (code, AMD64_R14);
 330         amd64_push_reg (code, AMD64_R13);
 331
 332         amd64_mov_reg_imm (code, AMD64_R11, throw_exception);
 333         amd64_call_reg (code, AMD64_R11);
 334         amd64_breakpoint (code);
 335
 336         g_assert ((code - start) < 64);
 337
 338         return start;
 339 }
 340
 341 /**
 342  * mono_arch_get_throw_exception:
 343  *
 344  * Returns a function pointer which can be used to raise
 345  * exceptions. The returned function has the following
 346  * signature: void (*func) (MonoException *exc);
 347  *
 348  */
 349 gpointer
 350 mono_arch_get_throw_exception (void)
 351 {
 352         static guint8* start;
 353         static gboolean inited = FALSE;
 354
 355         if (inited)
 356                 return start;
 357
 358         start = get_throw_trampoline (FALSE);
 359
 360         inited = TRUE;
 361
 362         return start;
 363 }
 364
 365 gpointer
 366 mono_arch_get_rethrow_exception (void)
 367 {
 368         static guint8* start;
 369         static gboolean inited = FALSE;
 370
 371         if (inited)
 372                 return start;
 373
 374         start = get_throw_trampoline (TRUE);
 375
 376         inited = TRUE;
 377
 378         return start;
 379 }
 380
 381 gpointer
 382 mono_arch_get_throw_exception_by_name (void)
 383 {
 384         static guint8* start;
 385         static gboolean inited = FALSE;
 386         guint8 *code;
 387
 388         if (inited)
 389                 return start;
 390
 391         start = code = mono_global_codeman_reserve (64);
 392
 393         /* Not used on amd64 */
 394         amd64_breakpoint (code);
 395
 396         return start;
 397 }
 398
 399 /**
 400  * mono_arch_get_throw_corlib_exception:
 401  *
 402  * Returns a function pointer which can be used to raise
 403  * corlib exceptions. The returned function has the following
 404  * signature: void (*func) (guint32 ex_token, guint32 offset);
 405  * Here, offset is the offset which needs to be substracted from the caller IP
 406  * to get the IP of the throw. Passing the offset has the advantage that it
 407  * needs no relocations in the caller.
 408  */
 409 gpointer
 410 mono_arch_get_throw_corlib_exception (void)
 411 {
 412         static guint8* start;
 413         static gboolean inited = FALSE;
 414         guint8 *code;
 415         guint64 throw_ex;
 416
 417         if (inited)
 418                 return start;
 419
 420         start = code = mono_global_codeman_reserve (64);
 421
 422         /* Push throw_ip */
 423         amd64_push_reg (code, AMD64_RSI);
 424
 425         /* Call exception_from_token */
 426         amd64_mov_reg_reg (code, AMD64_RSI, AMD64_RDI, 8);
 427         amd64_mov_reg_imm (code, AMD64_RDI, mono_defaults.exception_class->image);
 428         amd64_mov_reg_imm (code, AMD64_R11, mono_exception_from_token);
 429         amd64_call_reg (code, AMD64_R11);
 430
 431         /* Compute throw_ip */
 432         amd64_pop_reg (code, AMD64_RSI);
 433         /* return addr */
 434         amd64_pop_reg (code, AMD64_RDX);
 435         amd64_alu_reg_reg (code, X86_SUB, AMD64_RDX, AMD64_RSI);
 436
 437         /* Put the throw_ip at the top of the misaligned stack */
 438         amd64_push_reg (code, AMD64_RDX);
 439
 440         throw_ex = (guint64)mono_arch_get_throw_exception ();
 441
 442         /* Call throw_exception */
 443         amd64_mov_reg_reg (code, AMD64_RDI, AMD64_RAX, 8);
 444         amd64_mov_reg_imm (code, AMD64_R11, throw_ex);
 445         /* The original IP is on the stack */
 446         amd64_jump_reg (code, AMD64_R11);
 447
 448         g_assert ((code - start) < 64);
 449
 450         inited = TRUE;
 451
 452         return start;
 453 }
 454
 455 /* mono_arch_find_jit_info:
 456  *
 457  * This function is used to gather information from @ctx. It return the
 458  * MonoJitInfo of the corresponding function, unwinds one stack frame and
 459  * stores the resulting context into @new_ctx. It also stores a string
 460  * describing the stack location into @trace (if not NULL), and modifies
 461  * the @lmf if necessary. @native_offset return the IP offset from the
 462  * start of the function or -1 if that info is not available.
 463  */
 464 MonoJitInfo *
 465 mono_arch_find_jit_info (MonoDomain *domain, MonoJitTlsData *jit_tls, MonoJitInfo *res, MonoJitInfo *prev_ji, MonoContext *ctx,
 466                          MonoContext *new_ctx, char **trace, MonoLMF **lmf, int *native_offset,
 467                          gboolean *managed)
 468 {
 469         MonoJitInfo *ji;
 470         int i;
 471         gpointer ip = MONO_CONTEXT_GET_IP (ctx);
 472
 473         /* Avoid costly table lookup during stack overflow */
 474         if (prev_ji && (ip > prev_ji->code_start && ((guint8*)ip < ((guint8*)prev_ji->code_start) + prev_ji->code_size)))
 475                 ji = prev_ji;
 476         else
 477                 ji = mono_jit_info_table_find (domain, ip);
 478
 479         if (managed)
 480                 *managed = FALSE;
 481
 482         if (ji != NULL) {
 483                 int offset;
 484                 gboolean omit_fp = (ji->used_regs & (1 << 31)) > 0;
 485
 486                 *new_ctx = *ctx;
 487
 488                 if (managed)
 489                         if (!ji->method->wrapper_type)
 490                                 *managed = TRUE;
 491
 492                 /*
 493                  * Some managed methods like pinvoke wrappers might have save_lmf set.
 494                  * In this case, register save/restore code is not generated by the
 495                  * JIT, so we have to restore callee saved registers from the lmf.
 496                  */
 497                 if (ji->method->save_lmf) {
 498                         /*
 499                          * We only need to do this if the exception was raised in managed
 500                          * code, since otherwise the lmf was already popped of the stack.
 501                          */
 502                         if (*lmf && ((*lmf) != jit_tls->first_lmf) && (MONO_CONTEXT_GET_SP (ctx) >= (gpointer)(*lmf)->rsp)) {
 503                                 new_ctx->rbp = (*lmf)->ebp;
 504                                 new_ctx->rbx = (*lmf)->rbx;
 505                                 new_ctx->rsp = (*lmf)->rsp;
 506                                 new_ctx->r12 = (*lmf)->r12;
 507                                 new_ctx->r13 = (*lmf)->r13;
 508                                 new_ctx->r14 = (*lmf)->r14;
 509                                 new_ctx->r15 = (*lmf)->r15;
 510                         }
 511                 }
 512                 else {
 513                         offset = omit_fp ? 0 : -1;
 514                         /* restore caller saved registers */
 515                         for (i = 0; i < AMD64_NREG; i ++)
 516                                 if (AMD64_IS_CALLEE_SAVED_REG (i) && (ji->used_regs & (1 << i))) {
 517                                         guint64 reg;
 518
 519                                         if (omit_fp) {
 520                                                 reg = *((guint64*)ctx->rsp + offset);
 521                                                 offset ++;
 522                                         }
 523                                         else {
 524                                                 reg = *((guint64 *)ctx->rbp + offset);
 525                                                 offset --;
 526                                         }
 527
 528                                         switch (i) {
 529                                         case AMD64_RBX:
 530                                                 new_ctx->rbx = reg;
 531                                                 break;
 532                                         case AMD64_R12:
 533                                                 new_ctx->r12 = reg;
 534                                                 break;
 535                                         case AMD64_R13:
 536                                                 new_ctx->r13 = reg;
 537                                                 break;
 538                                         case AMD64_R14:
 539                                                 new_ctx->r14 = reg;
 540                                                 break;
 541                                         case AMD64_R15:
 542                                                 new_ctx->r15 = reg;
 543                                                 break;
 544                                         case AMD64_RBP:
 545                                                 new_ctx->rbp = reg;
 546                                                 break;
 547                                         default:
 548                                                 g_assert_not_reached ();
 549                                         }
 550                                 }
 551                 }
 552
 553                 if (*lmf && ((*lmf) != jit_tls->first_lmf) && (MONO_CONTEXT_GET_SP (ctx) >= (gpointer)(*lmf)->rsp)) {
 554                         /* remove any unused lmf */
 555                         *lmf = (*lmf)->previous_lmf;
 556                 }
 557
 558                 if (omit_fp) {
 559                         /* Pop frame */
 560                         new_ctx->rsp += (ji->used_regs >> 16) & (0x7fff);
 561                         new_ctx->rip = *((guint64 *)new_ctx->rsp) - 1;
 562                         /* Pop return address */
 563                         new_ctx->rsp += 8;
 564                 }
 565                 else {
 566                         /* Pop EBP and the return address */
 567                         new_ctx->rsp = ctx->rbp + (2 * sizeof (gpointer));
 568                         /* we substract 1, so that the IP points into the call instruction */
 569                         new_ctx->rip = *((guint64 *)ctx->rbp + 1) - 1;
 570                         new_ctx->rbp = *((guint64 *)ctx->rbp);
 571                 }
 572
 573                 /* Pop arguments off the stack */
 574                 {
 575                         MonoJitArgumentInfo *arg_info = g_newa (MonoJitArgumentInfo, mono_method_signature (ji->method)->param_count + 1);
 576
 577                         guint32 stack_to_pop = mono_arch_get_argument_info (mono_method_signature (ji->method), mono_method_signature (ji->method)->param_count, arg_info);
 578                         new_ctx->rsp += stack_to_pop;
 579                 }
 580
 581                 return ji;
 582         } else if (*lmf) {
 583
 584                 *new_ctx = *ctx;
 585
 586                 if ((ji = mono_jit_info_table_find (domain, (gpointer)(*lmf)->rip))) {
 587                 } else {
 588                         if (!(*lmf)->method)
 589                                 /* Top LMF entry */
 590                                 return (gpointer)-1;
 591                         /* Trampoline lmf frame */
 592                         memset (res, 0, sizeof (MonoJitInfo));
 593                         res->method = (*lmf)->method;
 594                 }
 595
 596                 new_ctx->rip = (*lmf)->rip;
 597                 new_ctx->rbp = (*lmf)->ebp;
 598                 new_ctx->rsp = (*lmf)->rsp;
 599
 600                 new_ctx->rbx = (*lmf)->rbx;
 601                 new_ctx->r12 = (*lmf)->r12;
 602                 new_ctx->r13 = (*lmf)->r13;
 603                 new_ctx->r14 = (*lmf)->r14;
 604                 new_ctx->r15 = (*lmf)->r15;
 605
 606                 *lmf = (*lmf)->previous_lmf;
 607
 608                 return ji ? ji : res;
 609         }
 610
 611         return NULL;
 612 }
 613
 614 /**
 615  * mono_arch_handle_exception:
 616  *
 617  * @ctx: saved processor state
 618  * @obj: the exception object
 619  */
 620 gboolean
 621 mono_arch_handle_exception (void *sigctx, gpointer obj, gboolean test_only)
 622 {
 623         MonoContext mctx;
 624
 625         mono_arch_sigctx_to_monoctx (sigctx, &mctx);
 626
 627         mono_handle_exception (&mctx, obj, MONO_CONTEXT_GET_IP (&mctx), test_only);
 628
 629         mono_arch_monoctx_to_sigctx (&mctx, sigctx);
 630
 631         return TRUE;
 632 }
 633
 634 static inline guint64*
 635 gregs_from_ucontext (ucontext_t *ctx)
 636 {
 637 #ifdef __FreeBSD__
 638     guint64 *gregs = (guint64 *) &ctx->uc_mcontext;
 639 #else
 640     guint64 *gregs = (guint64 *) &ctx->uc_mcontext.gregs;
 641 #endif
 642
 643         return gregs;
 644 }
 645
 646 void
 647 mono_arch_sigctx_to_monoctx (void *sigctx, MonoContext *mctx)
 648 {
 649         ucontext_t *ctx = (ucontext_t*)sigctx;
 650
 651     guint64 *gregs = gregs_from_ucontext (ctx);
 652
 653         mctx->rax = gregs [REG_RAX];
 654         mctx->rbx = gregs [REG_RBX];
 655         mctx->rcx = gregs [REG_RCX];
 656         mctx->rdx = gregs [REG_RDX];
 657         mctx->rbp = gregs [REG_RBP];
 658         mctx->rsp = gregs [REG_RSP];
 659         mctx->rsi = gregs [REG_RSI];
 660         mctx->rdi = gregs [REG_RDI];
 661         mctx->rip = gregs [REG_RIP];
 662         mctx->r12 = gregs [REG_R12];
 663         mctx->r13 = gregs [REG_R13];
 664         mctx->r14 = gregs [REG_R14];
 665         mctx->r15 = gregs [REG_R15];
 666 }
 667
 668 void
 669 mono_arch_monoctx_to_sigctx (MonoContext *mctx, void *sigctx)
 670 {
 671         ucontext_t *ctx = (ucontext_t*)sigctx;
 672
 673     guint64 *gregs = gregs_from_ucontext (ctx);
 674
 675         gregs [REG_RAX] = mctx->rax;
 676         gregs [REG_RBX] = mctx->rbx;
 677         gregs [REG_RCX] = mctx->rcx;
 678         gregs [REG_RDX] = mctx->rdx;
 679         gregs [REG_RBP] = mctx->rbp;
 680         gregs [REG_RSP] = mctx->rsp;
 681         gregs [REG_RSI] = mctx->rsi;
 682         gregs [REG_RDI] = mctx->rdi;
 683         gregs [REG_RIP] = mctx->rip;
 684         gregs [REG_R12] = mctx->r12;
 685         gregs [REG_R13] = mctx->r13;
 686         gregs [REG_R14] = mctx->r14;
 687         gregs [REG_R15] = mctx->r15;
 688 }
 689
 690 gpointer
 691 mono_arch_ip_from_context (void *sigctx)
 692 {
 693         ucontext_t *ctx = (ucontext_t*)sigctx;
 694
 695     guint64 *gregs = gregs_from_ucontext (ctx);
 696
 697         return (gpointer)gregs [REG_RIP];
 698 }
 699