2 * exceptions-x86.c: exception support for x86
5 * Dietmar Maurer (dietmar@ximian.com)
7 * (C) 2001 Ximian, Inc.
16 #include <mono/metadata/abi-details.h>
17 #include <mono/arch/x86/x86-codegen.h>
18 #include <mono/metadata/appdomain.h>
19 #include <mono/metadata/tabledefs.h>
20 #include <mono/metadata/threads.h>
21 #include <mono/metadata/debug-helpers.h>
22 #include <mono/metadata/exception.h>
23 #include <mono/metadata/gc-internal.h>
24 #include <mono/metadata/mono-debug.h>
25 #include <mono/utils/mono-mmap.h>
31 static gpointer signal_exception_trampoline;
34 mono_x86_get_signal_exception_trampoline (MonoTrampInfo **info, gboolean aot) MONO_INTERNAL;
37 static void (*restore_stack) (void *);
39 static MonoW32ExceptionHandler fpe_handler;
40 static MonoW32ExceptionHandler ill_handler;
41 static MonoW32ExceptionHandler segv_handler;
43 LPTOP_LEVEL_EXCEPTION_FILTER mono_old_win_toplevel_exception_filter;
44 gpointer mono_win_vectored_exception_handle;
45 extern int (*gUnhandledExceptionHandler)(EXCEPTION_POINTERS*);
47 #ifndef PROCESS_CALLBACK_FILTER_ENABLED
48 # define PROCESS_CALLBACK_FILTER_ENABLED 1
51 #define W32_SEH_HANDLE_EX(_ex) \
52 if (_ex##_handler) _ex##_handler(0, ep, ctx)
54 LONG CALLBACK seh_unhandled_exception_filter(EXCEPTION_POINTERS* ep)
56 #ifndef MONO_CROSS_COMPILE
57 if (mono_old_win_toplevel_exception_filter) {
58 return (*mono_old_win_toplevel_exception_filter)(ep);
62 mono_handle_native_sigsegv (SIGSEGV, NULL);
64 return EXCEPTION_CONTINUE_SEARCH;
68 * mono_win32_get_handle_stackoverflow (void):
70 * Returns a pointer to a method which restores the current context stack
71 * and calls handle_exceptions, when done restores the original stack.
74 mono_win32_get_handle_stackoverflow (void)
76 static guint8 *start = NULL;
82 /* restore_contect (void *sigctx) */
83 start = code = mono_global_codeman_reserve (128);
85 /* load context into ebx */
86 x86_mov_reg_membase (code, X86_EBX, X86_ESP, 4, 4);
88 /* move current stack into edi for later restore */
89 x86_mov_reg_reg (code, X86_EDI, X86_ESP, 4);
91 /* use the new freed stack from sigcontext */
92 /* XXX replace usage of struct sigcontext with MonoContext so we can use MONO_STRUCT_OFFSET */
93 x86_mov_reg_membase (code, X86_ESP, X86_EBX, G_STRUCT_OFFSET (struct sigcontext, esp), 4);
95 /* get the current domain */
96 x86_call_code (code, mono_domain_get);
98 /* get stack overflow exception from domain object */
99 x86_mov_reg_membase (code, X86_EAX, X86_EAX, MONO_STRUCT_OFFSET (MonoDomain, stack_overflow_ex), 4);
101 /* call mono_arch_handle_exception (sctx, stack_overflow_exception_obj) */
102 x86_push_reg (code, X86_EAX);
103 x86_push_reg (code, X86_EBX);
104 x86_call_code (code, mono_arch_handle_exception);
106 /* restore the SEH handler stack */
107 x86_mov_reg_reg (code, X86_ESP, X86_EDI, 4);
115 /* Special hack to workaround the fact that the
116 * when the SEH handler is called the stack is
117 * to small to recover.
119 * Stack walking part of this method is from mono_handle_exception
121 * The idea is simple;
122 * - walk the stack to free some space (64k)
123 * - set esp to new stack location
124 * - call mono_arch_handle_exception with stack overflow exception
125 * - set esp to SEH handlers stack
129 win32_handle_stack_overflow (EXCEPTION_POINTERS* ep, struct sigcontext *sctx)
133 MonoDomain *domain = mono_domain_get ();
135 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
136 MonoLMF *lmf = jit_tls->lmf;
137 MonoContext initial_ctx;
139 guint32 free_stack = 0;
140 StackFrameInfo frame;
142 /* convert sigcontext to MonoContext (due to reuse of stack walking helpers */
143 mono_arch_sigctx_to_monoctx (sctx, &ctx);
145 /* get our os page size */
147 page_size = si.dwPageSize;
149 /* Let's walk the stack to recover
150 * the needed stack space (if possible)
152 memset (&rji, 0, sizeof (rji));
155 free_stack = (guint8*)(MONO_CONTEXT_GET_BP (&ctx)) - (guint8*)(MONO_CONTEXT_GET_BP (&initial_ctx));
157 /* try to free 64kb from our stack */
161 mono_arch_find_jit_info (domain, jit_tls, &rji, &ctx, &new_ctx, &lmf, NULL, &frame);
163 g_warning ("Exception inside function without unwind info");
164 g_assert_not_reached ();
167 if (frame.ji != (gpointer)-1) {
168 free_stack = (guint8*)(MONO_CONTEXT_GET_BP (&ctx)) - (guint8*)(MONO_CONTEXT_GET_BP (&initial_ctx));
171 /* todo: we should call abort if ji is -1 */
173 } while (free_stack < 64 * 1024 && frame.ji != (gpointer) -1);
175 /* convert into sigcontext to be used in mono_arch_handle_exception */
176 mono_arch_monoctx_to_sigctx (&ctx, sctx);
178 /* todo: install new stack-guard page */
180 /* use the new stack and call mono_arch_handle_exception () */
181 restore_stack (sctx);
185 * Unhandled Exception Filter
186 * Top-level per-process exception handler.
188 LONG CALLBACK seh_vectored_exception_handler(EXCEPTION_POINTERS* ep)
190 EXCEPTION_RECORD* er;
193 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
195 /* If the thread is not managed by the runtime return early */
197 return EXCEPTION_CONTINUE_SEARCH;
199 jit_tls->mono_win_chained_exception_needs_run = FALSE;
200 res = EXCEPTION_CONTINUE_EXECUTION;
202 er = ep->ExceptionRecord;
203 ctx = ep->ContextRecord;
205 switch (er->ExceptionCode) {
206 case EXCEPTION_STACK_OVERFLOW:
207 win32_handle_stack_overflow (ep, sctx);
209 case EXCEPTION_ACCESS_VIOLATION:
210 W32_SEH_HANDLE_EX(segv);
212 case EXCEPTION_ILLEGAL_INSTRUCTION:
213 W32_SEH_HANDLE_EX(ill);
215 case EXCEPTION_INT_DIVIDE_BY_ZERO:
216 case EXCEPTION_INT_OVERFLOW:
217 case EXCEPTION_FLT_DIVIDE_BY_ZERO:
218 case EXCEPTION_FLT_OVERFLOW:
219 case EXCEPTION_FLT_UNDERFLOW:
220 case EXCEPTION_FLT_INEXACT_RESULT:
221 W32_SEH_HANDLE_EX(fpe);
224 jit_tls->mono_win_chained_exception_needs_run = TRUE;
228 if (jit_tls->mono_win_chained_exception_needs_run) {
229 /* Don't copy context back if we chained exception
230 * as the handler may have modfied the EXCEPTION_POINTERS
231 * directly. We don't pass sigcontext to chained handlers.
232 * Return continue search so the UnhandledExceptionFilter
233 * can correctly chain the exception.
235 res = EXCEPTION_CONTINUE_SEARCH;
241 void win32_seh_init()
243 /* install restore stack helper */
245 restore_stack = mono_win32_get_handle_stackoverflow ();
247 mono_old_win_toplevel_exception_filter = SetUnhandledExceptionFilter(seh_unhandled_exception_filter);
248 mono_win_vectored_exception_handle = AddVectoredExceptionHandler (1, seh_vectored_exception_handler);
251 void win32_seh_cleanup()
253 if (mono_old_win_toplevel_exception_filter) SetUnhandledExceptionFilter(mono_old_win_toplevel_exception_filter);
254 RemoveVectoredExceptionHandler (seh_unhandled_exception_filter);
257 void win32_seh_set_handler(int type, MonoW32ExceptionHandler handler)
261 fpe_handler = handler;
264 ill_handler = handler;
267 segv_handler = handler;
274 #endif /* TARGET_WIN32 */
277 * mono_arch_get_restore_context:
279 * Returns a pointer to a method which restores a previously saved sigcontext.
282 mono_arch_get_restore_context (MonoTrampInfo **info, gboolean aot)
284 guint8 *start = NULL;
286 MonoJumpInfo *ji = NULL;
287 GSList *unwind_ops = NULL;
289 /* restore_contect (MonoContext *ctx) */
291 start = code = mono_global_codeman_reserve (128);
294 x86_mov_reg_membase (code, X86_EAX, X86_ESP, 4, 4);
297 x86_mov_reg_membase (code, X86_EBX, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, ebx), 4);
300 x86_mov_reg_membase (code, X86_EDI, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, edi), 4);
303 x86_mov_reg_membase (code, X86_ESI, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, esi), 4);
306 x86_mov_reg_membase (code, X86_EDX, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, edx), 4);
309 * The context resides on the stack, in the stack frame of the
310 * caller of this function. The stack pointer that we need to
311 * restore is potentially many stack frames higher up, so the
312 * distance between them can easily be more than the red zone
313 * size. Hence the stack pointer can be restored only after
314 * we have finished loading everything from the context.
317 /* load ESP into EBP */
318 x86_mov_reg_membase (code, X86_EBP, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, esp), 4);
319 /* load return address into ECX */
320 x86_mov_reg_membase (code, X86_ECX, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, eip), 4);
321 /* save the return addr to the restored stack - 4 */
322 x86_mov_membase_reg (code, X86_EBP, -4, X86_ECX, 4);
324 /* load EBP into ECX */
325 x86_mov_reg_membase (code, X86_ECX, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, ebp), 4);
326 /* save EBP to the restored stack - 8 */
327 x86_mov_membase_reg (code, X86_EBP, -8, X86_ECX, 4);
329 /* load EAX into ECX */
330 x86_mov_reg_membase (code, X86_ECX, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, eax), 4);
331 /* save EAX to the restored stack - 12 */
332 x86_mov_membase_reg (code, X86_EBP, -12, X86_ECX, 4);
335 x86_mov_reg_membase (code, X86_ECX, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, ecx), 4);
337 /* restore ESP - 12 */
338 x86_lea_membase (code, X86_ESP, X86_EBP, -12);
340 x86_pop_reg (code, X86_EAX);
342 x86_pop_reg (code, X86_EBP);
343 /* jump to the saved IP */
346 nacl_global_codeman_validate(&start, 128, &code);
349 *info = mono_tramp_info_create ("restore_context", start, code - start, ji, unwind_ops);
353 for (l = unwind_ops; l; l = l->next)
355 g_slist_free (unwind_ops);
362 * mono_arch_get_call_filter:
364 * Returns a pointer to a method which calls an exception filter. We
365 * also use this function to call finally handlers (we pass NULL as
366 * @exc object in this case).
369 mono_arch_get_call_filter (MonoTrampInfo **info, gboolean aot)
373 MonoJumpInfo *ji = NULL;
374 GSList *unwind_ops = NULL;
375 guint kMaxCodeSize = NACL_SIZE (64, 128);
377 /* call_filter (MonoContext *ctx, unsigned long eip) */
378 start = code = mono_global_codeman_reserve (kMaxCodeSize);
380 x86_push_reg (code, X86_EBP);
381 x86_mov_reg_reg (code, X86_EBP, X86_ESP, 4);
382 x86_push_reg (code, X86_EBX);
383 x86_push_reg (code, X86_EDI);
384 x86_push_reg (code, X86_ESI);
387 x86_mov_reg_membase (code, X86_EAX, X86_EBP, 8, 4);
389 x86_mov_reg_membase (code, X86_ECX, X86_EBP, 12, 4);
391 x86_push_reg (code, X86_EBP);
394 x86_mov_reg_membase (code, X86_EBP, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, ebp), 4);
395 /* restore registers used by global register allocation (EBX & ESI) */
396 x86_mov_reg_membase (code, X86_EBX, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, ebx), 4);
397 x86_mov_reg_membase (code, X86_ESI, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, esi), 4);
398 x86_mov_reg_membase (code, X86_EDI, X86_EAX, MONO_STRUCT_OFFSET (MonoContext, edi), 4);
400 /* align stack and save ESP */
401 x86_mov_reg_reg (code, X86_EDX, X86_ESP, 4);
402 x86_alu_reg_imm (code, X86_AND, X86_ESP, -MONO_ARCH_FRAME_ALIGNMENT);
403 g_assert (MONO_ARCH_FRAME_ALIGNMENT >= 8);
404 x86_alu_reg_imm (code, X86_SUB, X86_ESP, MONO_ARCH_FRAME_ALIGNMENT - 8);
405 x86_push_reg (code, X86_EDX);
407 /* call the handler */
408 x86_call_reg (code, X86_ECX);
411 x86_pop_reg (code, X86_ESP);
414 x86_pop_reg (code, X86_EBP);
416 /* restore saved regs */
417 x86_pop_reg (code, X86_ESI);
418 x86_pop_reg (code, X86_EDI);
419 x86_pop_reg (code, X86_EBX);
423 nacl_global_codeman_validate(&start, kMaxCodeSize, &code);
426 *info = mono_tramp_info_create ("call_filter", start, code - start, ji, unwind_ops);
430 for (l = unwind_ops; l; l = l->next)
432 g_slist_free (unwind_ops);
435 g_assert ((code - start) < kMaxCodeSize);
440 * mono_x86_throw_exception:
442 * C function called from the throw trampolines.
445 mono_x86_throw_exception (mgreg_t *regs, MonoObject *exc,
446 mgreg_t eip, gboolean rethrow)
450 ctx.esp = regs [X86_ESP];
452 ctx.ebp = regs [X86_EBP];
453 ctx.edi = regs [X86_EDI];
454 ctx.esi = regs [X86_ESI];
455 ctx.ebx = regs [X86_EBX];
456 ctx.edx = regs [X86_EDX];
457 ctx.ecx = regs [X86_ECX];
458 ctx.eax = regs [X86_EAX];
461 /* The OSX ABI specifies 16 byte alignment at call sites */
462 g_assert ((ctx.esp % MONO_ARCH_FRAME_ALIGNMENT) == 0);
465 if (mono_object_isinst (exc, mono_defaults.exception_class)) {
466 MonoException *mono_ex = (MonoException*)exc;
468 mono_ex->stack_trace = NULL;
471 /* adjust eip so that it point into the call instruction */
474 mono_handle_exception (&ctx, exc);
476 mono_restore_context (&ctx);
478 g_assert_not_reached ();
482 mono_x86_throw_corlib_exception (mgreg_t *regs, guint32 ex_token_index,
483 mgreg_t eip, gint32 pc_offset)
485 guint32 ex_token = MONO_TOKEN_TYPE_DEF | ex_token_index;
488 ex = mono_exception_from_token (mono_defaults.exception_class->image, ex_token);
492 /* Negate the ip adjustment done in mono_x86_throw_exception () */
495 mono_x86_throw_exception (regs, (MonoObject*)ex, eip, FALSE);
499 mono_x86_resume_unwind (mgreg_t *regs, MonoObject *exc,
500 mgreg_t eip, gboolean rethrow)
504 ctx.esp = regs [X86_ESP];
506 ctx.ebp = regs [X86_EBP];
507 ctx.edi = regs [X86_EDI];
508 ctx.esi = regs [X86_ESI];
509 ctx.ebx = regs [X86_EBX];
510 ctx.edx = regs [X86_EDX];
511 ctx.ecx = regs [X86_ECX];
512 ctx.eax = regs [X86_EAX];
514 mono_resume_unwind (&ctx);
518 * get_throw_trampoline:
520 * Generate a call to mono_x86_throw_exception/
521 * mono_x86_throw_corlib_exception.
522 * If LLVM is true, generate code which assumes the caller is LLVM generated code,
523 * which doesn't push the arguments.
526 get_throw_trampoline (const char *name, gboolean rethrow, gboolean llvm, gboolean corlib, gboolean llvm_abs, gboolean resume_unwind, MonoTrampInfo **info, gboolean aot)
528 guint8 *start, *code;
529 int i, stack_size, stack_offset, arg_offsets [5], regs_offset;
530 MonoJumpInfo *ji = NULL;
531 GSList *unwind_ops = NULL;
532 guint kMaxCodeSize = NACL_SIZE (128, 256);
534 start = code = mono_global_codeman_reserve (kMaxCodeSize);
539 * On apple, the stack is misaligned by the pushing of the return address.
542 /* On OSX, we don't generate alignment code to save space */
545 stack_size += MONO_ARCH_FRAME_ALIGNMENT - 4;
548 * The stack looks like this:
549 * <pc offset> (only if corlib is TRUE)
550 * <exception object>/<type token>
551 * <return addr> <- esp (unaligned on apple)
554 mono_add_unwind_op_def_cfa (unwind_ops, (guint8*)NULL, (guint8*)NULL, X86_ESP, 4);
555 mono_add_unwind_op_offset (unwind_ops, (guint8*)NULL, (guint8*)NULL, X86_NREG, -4);
558 x86_alu_reg_imm (code, X86_SUB, X86_ESP, stack_size);
559 mono_add_unwind_op_def_cfa_offset (unwind_ops, code, start, stack_size + 4);
564 arg_offsets [3] = 12;
568 for (i = 0; i < X86_NREG; ++i)
570 x86_mov_membase_reg (code, X86_ESP, regs_offset + (i * 4), i, 4);
571 /* Calculate the offset between the current sp and the sp of the caller */
573 /* LLVM doesn't push the arguments */
574 stack_offset = stack_size + 4;
578 stack_offset = stack_size + 4 + 8;
580 /* We don't generate stack alignment code on osx to save space */
583 /* One argument + stack alignment */
584 stack_offset = stack_size + 4 + 4;
586 /* Pop the alignment added by OP_THROW too */
587 stack_offset += MONO_ARCH_FRAME_ALIGNMENT - 4;
589 if (mono_do_x86_stack_align)
590 stack_offset += MONO_ARCH_FRAME_ALIGNMENT - 4;
595 x86_lea_membase (code, X86_EAX, X86_ESP, stack_offset);
596 x86_mov_membase_reg (code, X86_ESP, regs_offset + (X86_ESP * 4), X86_EAX, 4);
598 /* Set arg1 == regs */
599 x86_lea_membase (code, X86_EAX, X86_ESP, regs_offset);
600 x86_mov_membase_reg (code, X86_ESP, arg_offsets [0], X86_EAX, 4);
601 /* Set arg2 == exc/ex_token_index */
603 x86_mov_reg_imm (code, X86_EAX, 0);
605 x86_mov_reg_membase (code, X86_EAX, X86_ESP, stack_size + 4, 4);
606 x86_mov_membase_reg (code, X86_ESP, arg_offsets [1], X86_EAX, 4);
607 /* Set arg3 == eip */
609 x86_alu_reg_reg (code, X86_XOR, X86_EAX, X86_EAX);
611 x86_mov_reg_membase (code, X86_EAX, X86_ESP, stack_size, 4);
612 x86_mov_membase_reg (code, X86_ESP, arg_offsets [2], X86_EAX, 4);
613 /* Set arg4 == rethrow/pc_offset */
615 x86_mov_membase_imm (code, X86_ESP, arg_offsets [3], 0, 4);
617 x86_mov_reg_membase (code, X86_EAX, X86_ESP, stack_size + 8, 4);
620 * The caller is LLVM code which passes the absolute address not a pc offset,
621 * so compensate by passing 0 as 'ip' and passing the negated abs address as
624 x86_neg_reg (code, X86_EAX);
626 x86_mov_membase_reg (code, X86_ESP, arg_offsets [3], X86_EAX, 4);
628 x86_mov_membase_imm (code, X86_ESP, arg_offsets [3], rethrow, 4);
632 // This can be called from runtime code, which can't guarantee that
633 // ebx contains the got address.
634 // So emit the got address loading code too
635 code = mono_arch_emit_load_got_addr (start, code, NULL, &ji);
636 code = mono_arch_emit_load_aotconst (start, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, corlib ? "mono_x86_throw_corlib_exception" : "mono_x86_throw_exception");
637 x86_call_reg (code, X86_EAX);
639 x86_call_code (code, resume_unwind ? (gpointer)(mono_x86_resume_unwind) : (corlib ? (gpointer)mono_x86_throw_corlib_exception : (gpointer)mono_x86_throw_exception));
641 x86_breakpoint (code);
643 nacl_global_codeman_validate(&start, kMaxCodeSize, &code);
645 g_assert ((code - start) < kMaxCodeSize);
648 *info = mono_tramp_info_create (name, start, code - start, ji, unwind_ops);
652 for (l = unwind_ops; l; l = l->next)
654 g_slist_free (unwind_ops);
661 * mono_arch_get_throw_exception:
663 * Returns a function pointer which can be used to raise
664 * exceptions. The returned function has the following
665 * signature: void (*func) (MonoException *exc);
666 * For example to raise an arithmetic exception you can use:
668 * x86_push_imm (code, mono_get_exception_arithmetic ());
669 * x86_call_code (code, arch_get_throw_exception ());
673 mono_arch_get_throw_exception (MonoTrampInfo **info, gboolean aot)
675 return get_throw_trampoline ("throw_exception", FALSE, FALSE, FALSE, FALSE, FALSE, info, aot);
679 mono_arch_get_rethrow_exception (MonoTrampInfo **info, gboolean aot)
681 return get_throw_trampoline ("rethrow_exception", TRUE, FALSE, FALSE, FALSE, FALSE, info, aot);
685 * mono_arch_get_throw_corlib_exception:
687 * Returns a function pointer which can be used to raise
688 * corlib exceptions. The returned function has the following
689 * signature: void (*func) (guint32 ex_token, guint32 offset);
690 * Here, offset is the offset which needs to be substracted from the caller IP
691 * to get the IP of the throw. Passing the offset has the advantage that it
692 * needs no relocations in the caller.
695 mono_arch_get_throw_corlib_exception (MonoTrampInfo **info, gboolean aot)
697 return get_throw_trampoline ("throw_corlib_exception", FALSE, FALSE, TRUE, FALSE, FALSE, info, aot);
701 mono_arch_exceptions_init (void)
706 * If we're running WoW64, we need to set the usermode exception policy
707 * for SEHs to behave. This requires hotfix http://support.microsoft.com/kb/976038
708 * or (eventually) Windows 7 SP1.
714 HMODULE kernel32 = LoadLibraryW (L"kernel32.dll");
717 getter = GetProcAddress (kernel32, "GetProcessUserModeExceptionPolicy");
718 setter = GetProcAddress (kernel32, "SetProcessUserModeExceptionPolicy");
719 if (getter && setter) {
721 setter (flags & ~PROCESS_CALLBACK_FILTER_ENABLED);
727 signal_exception_trampoline = mono_aot_get_trampoline ("x86_signal_exception_trampoline");
731 /* LLVM needs different throw trampolines */
732 tramp = get_throw_trampoline ("llvm_throw_exception_trampoline", FALSE, TRUE, FALSE, FALSE, FALSE, NULL, FALSE);
733 mono_register_jit_icall (tramp, "llvm_throw_exception_trampoline", NULL, TRUE);
735 tramp = get_throw_trampoline ("llvm_rethrow_exception_trampoline", FALSE, TRUE, FALSE, FALSE, FALSE, NULL, FALSE);
736 mono_register_jit_icall (tramp, "llvm_rethrow_exception_trampoline", NULL, TRUE);
738 tramp = get_throw_trampoline ("llvm_throw_corlib_exception_trampoline", FALSE, TRUE, TRUE, FALSE, FALSE, NULL, FALSE);
739 mono_register_jit_icall (tramp, "llvm_throw_corlib_exception_trampoline", NULL, TRUE);
741 tramp = get_throw_trampoline ("llvm_throw_corlib_exception_abs_trampoline", FALSE, TRUE, TRUE, TRUE, FALSE, NULL, FALSE);
742 mono_register_jit_icall (tramp, "llvm_throw_corlib_exception_abs_trampoline", NULL, TRUE);
744 tramp = get_throw_trampoline ("llvm_resume_unwind_trampoline", FALSE, FALSE, FALSE, FALSE, TRUE, NULL, FALSE);
745 mono_register_jit_icall (tramp, "llvm_resume_unwind_trampoline", NULL, TRUE);
747 signal_exception_trampoline = mono_x86_get_signal_exception_trampoline (NULL, FALSE);
751 * mono_arch_find_jit_info:
753 * See exceptions-amd64.c for docs.
756 mono_arch_find_jit_info (MonoDomain *domain, MonoJitTlsData *jit_tls,
757 MonoJitInfo *ji, MonoContext *ctx,
758 MonoContext *new_ctx, MonoLMF **lmf,
759 mgreg_t **save_locations,
760 StackFrameInfo *frame)
762 gpointer ip = MONO_CONTEXT_GET_IP (ctx);
764 memset (frame, 0, sizeof (StackFrameInfo));
770 gssize regs [MONO_MAX_IREGS + 1];
772 guint32 unwind_info_len;
775 frame->type = FRAME_TYPE_MANAGED;
777 unwind_info = mono_jinfo_get_unwind_info (ji, &unwind_info_len);
779 regs [X86_EAX] = new_ctx->eax;
780 regs [X86_EBX] = new_ctx->ebx;
781 regs [X86_ECX] = new_ctx->ecx;
782 regs [X86_EDX] = new_ctx->edx;
783 regs [X86_ESP] = new_ctx->esp;
784 regs [X86_EBP] = new_ctx->ebp;
785 regs [X86_ESI] = new_ctx->esi;
786 regs [X86_EDI] = new_ctx->edi;
787 regs [X86_NREG] = new_ctx->eip;
789 mono_unwind_frame (unwind_info, unwind_info_len, ji->code_start,
790 (guint8*)ji->code_start + ji->code_size,
791 ip, NULL, regs, MONO_MAX_IREGS + 1,
792 save_locations, MONO_MAX_IREGS, &cfa);
794 new_ctx->eax = regs [X86_EAX];
795 new_ctx->ebx = regs [X86_EBX];
796 new_ctx->ecx = regs [X86_ECX];
797 new_ctx->edx = regs [X86_EDX];
798 new_ctx->esp = regs [X86_ESP];
799 new_ctx->ebp = regs [X86_EBP];
800 new_ctx->esi = regs [X86_ESI];
801 new_ctx->edi = regs [X86_EDI];
802 new_ctx->eip = regs [X86_NREG];
804 /* The CFA becomes the new SP value */
805 new_ctx->esp = (gssize)cfa;
811 #ifndef MONO_X86_NO_PUSHES
812 /* Pop arguments off the stack */
813 if (ji->has_arch_eh_info) {
816 stack_size = mono_jit_info_get_arch_eh_info (ji)->stack_size;
820 MonoJitInfo *caller_ji;
822 caller_ji = mini_jit_info_table_find (domain, (char*)new_ctx->eip, NULL);
823 /* LLVM doesn't push the arguments */
824 if (caller_ji && !caller_ji->from_llvm)
825 new_ctx->esp += stack_size;
827 new_ctx->esp += stack_size;
836 if (((guint64)(*lmf)->previous_lmf) & 2) {
838 * This LMF entry is created by the soft debug code to mark transitions to
839 * managed code done during invokes.
841 MonoLMFExt *ext = (MonoLMFExt*)(*lmf);
843 g_assert (ext->debugger_invoke);
845 memcpy (new_ctx, &ext->ctx, sizeof (MonoContext));
847 *lmf = (gpointer)(((gsize)(*lmf)->previous_lmf) & ~3);
849 frame->type = FRAME_TYPE_DEBUGGER_INVOKE;
854 if ((ji = mini_jit_info_table_find (domain, (gpointer)(*lmf)->eip, NULL))) {
856 if (!((guint32)((*lmf)->previous_lmf) & 1))
859 g_assert_not_reached ();
860 /* Trampoline lmf frame */
861 frame->method = (*lmf)->method;
864 new_ctx->esi = (*lmf)->esi;
865 new_ctx->edi = (*lmf)->edi;
866 new_ctx->ebx = (*lmf)->ebx;
867 new_ctx->ebp = (*lmf)->ebp;
868 new_ctx->eip = (*lmf)->eip;
874 frame->type = FRAME_TYPE_MANAGED_TO_NATIVE;
876 /* Check if we are in a trampoline LMF frame */
877 if ((guint32)((*lmf)->previous_lmf) & 1) {
878 /* lmf->esp is set by the trampoline code */
879 new_ctx->esp = (*lmf)->esp;
881 /* Pop arguments off the stack */
882 /* FIXME: Handle the delegate case too ((*lmf)->method == NULL) */
883 /* FIXME: Handle the IMT/vtable case too */
886 if ((*lmf)->method) {
887 MonoMethod *method = (*lmf)->method;
888 MonoJitArgumentInfo *arg_info = g_newa (MonoJitArgumentInfo, mono_method_signature (method)->param_count + 1);
890 guint32 stack_to_pop = mono_arch_get_argument_info (NULL, mono_method_signature (method), mono_method_signature (method)->param_count, arg_info);
891 new_ctx->esp += stack_to_pop;
897 /* the lmf is always stored on the stack, so the following
898 * expression points to a stack location which can be used as ESP */
899 new_ctx->esp = (unsigned long)&((*lmf)->eip);
901 *lmf = (gpointer)(((gsize)(*lmf)->previous_lmf) & ~3);
910 mono_arch_sigctx_to_monoctx (void *sigctx, MonoContext *mctx)
912 mono_sigctx_to_monoctx (sigctx, mctx);
916 mono_arch_monoctx_to_sigctx (MonoContext *mctx, void *sigctx)
918 mono_monoctx_to_sigctx (mctx, sigctx);
922 mono_arch_ip_from_context (void *sigctx)
924 #if defined(__native_client__)
925 printf("WARNING: mono_arch_ip_from_context() called!\n");
927 #elif defined(MONO_ARCH_USE_SIGACTION)
928 ucontext_t *ctx = (ucontext_t*)sigctx;
929 return (gpointer)UCONTEXT_REG_EIP (ctx);
930 #elif defined(HOST_WIN32)
931 return ((CONTEXT*)sigctx)->Eip;
933 struct sigcontext *ctx = sigctx;
934 return (gpointer)ctx->SC_EIP;
941 * Called by resuming from a signal handler.
944 handle_signal_exception (gpointer obj)
946 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
949 memcpy (&ctx, &jit_tls->ex_ctx, sizeof (MonoContext));
951 mono_handle_exception (&ctx, obj);
953 mono_restore_context (&ctx);
957 * mono_x86_get_signal_exception_trampoline:
959 * This x86 specific trampoline is used to call handle_signal_exception.
962 mono_x86_get_signal_exception_trampoline (MonoTrampInfo **info, gboolean aot)
964 guint8 *start, *code;
965 MonoJumpInfo *ji = NULL;
966 GSList *unwind_ops = NULL;
969 start = code = mono_global_codeman_reserve (128);
972 x86_push_reg (code, X86_ECX);
974 mono_add_unwind_op_def_cfa (unwind_ops, (guint8*)NULL, (guint8*)NULL, X86_ESP, 4);
975 mono_add_unwind_op_offset (unwind_ops, (guint8*)NULL, (guint8*)NULL, X86_NREG, -4);
977 /* Fix the alignment to be what apple expects */
980 x86_alu_reg_imm (code, X86_SUB, X86_ESP, stack_size);
981 mono_add_unwind_op_def_cfa_offset (unwind_ops, code, start, stack_size + 4);
984 x86_mov_membase_reg (code, X86_ESP, 0, X86_EAX, 4);
985 /* Branch to target */
986 x86_call_reg (code, X86_EDX);
988 g_assert ((code - start) < 128);
991 *info = mono_tramp_info_create ("x86_signal_exception_trampoline", start, code - start, ji, unwind_ops);
995 for (l = unwind_ops; l; l = l->next)
997 g_slist_free (unwind_ops);
1005 mono_arch_setup_async_callback (MonoContext *ctx, void (*async_cb)(void *fun), gpointer user_data)
1008 * Can't pass the obj on the stack, since we are executing on the
1009 * same stack. Can't save it into MonoJitTlsData, since it needs GC tracking.
1010 * So put it into a register, and branch to a trampoline which
1013 ctx->eax = (mgreg_t)user_data;
1014 ctx->ecx = ctx->eip;
1015 ctx->edx = (mgreg_t)async_cb;
1018 ctx->esp = (ctx->esp - 16) & ~15;
1019 ctx->eip = (mgreg_t)signal_exception_trampoline;
1023 mono_arch_handle_exception (void *sigctx, gpointer obj)
1025 #if defined(MONO_ARCH_USE_SIGACTION)
1027 ucontext_t *ctx = (ucontext_t*)sigctx;
1030 * Handling the exception in the signal handler is problematic, since the original
1031 * signal is disabled, and we could run arbitrary code though the debugger. So
1032 * resume into the normal stack and do most work there if possible.
1034 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
1036 /* Pass the ctx parameter in TLS */
1037 mono_arch_sigctx_to_monoctx (ctx, &jit_tls->ex_ctx);
1039 mctx = jit_tls->ex_ctx;
1040 mono_setup_async_callback (&mctx, handle_signal_exception, obj);
1041 mono_monoctx_to_sigctx (&mctx, sigctx);
1044 #elif defined (TARGET_WIN32)
1046 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
1047 struct sigcontext *ctx = (struct sigcontext *)sigctx;
1049 mono_arch_sigctx_to_monoctx (sigctx, &jit_tls->ex_ctx);
1051 mctx = jit_tls->ex_ctx;
1052 mono_setup_async_callback (&mctx, handle_signal_exception, obj);
1053 mono_monoctx_to_sigctx (&mctx, sigctx);
1059 mono_arch_sigctx_to_monoctx (sigctx, &mctx);
1061 mono_handle_exception (&mctx, obj);
1063 mono_arch_monoctx_to_sigctx (&mctx, sigctx);
1070 restore_soft_guard_pages (void)
1072 MonoJitTlsData *jit_tls = mono_native_tls_get_value (mono_jit_tls_id);
1073 if (jit_tls->stack_ovf_guard_base)
1074 mono_mprotect (jit_tls->stack_ovf_guard_base, jit_tls->stack_ovf_guard_size, MONO_MMAP_NONE);
1078 * this function modifies mctx so that when it is restored, it
1079 * won't execcute starting at mctx.eip, but in a function that
1080 * will restore the protection on the soft-guard pages and return back to
1081 * continue at mctx.eip.
1084 prepare_for_guard_pages (MonoContext *mctx)
1087 sp = (gpointer)(mctx->esp);
1089 /* the resturn addr */
1090 sp [0] = (gpointer)(mctx->eip);
1091 mctx->eip = (unsigned long)restore_soft_guard_pages;
1092 mctx->esp = (unsigned long)sp;
1096 altstack_handle_and_restore (MonoContext *ctx, gpointer obj, gboolean stack_ovf)
1102 mono_handle_exception (&mctx, obj);
1104 prepare_for_guard_pages (&mctx);
1105 mono_restore_context (&mctx);
1109 mono_arch_handle_altstack_exception (void *sigctx, gpointer fault_addr, gboolean stack_ovf)
1111 #ifdef MONO_ARCH_USE_SIGACTION
1112 MonoException *exc = NULL;
1113 ucontext_t *ctx = (ucontext_t*)sigctx;
1114 MonoJitInfo *ji = mini_jit_info_table_find (mono_domain_get (), (gpointer)UCONTEXT_REG_EIP (ctx), NULL);
1118 /* if we didn't find a managed method for the ip address and it matches the fault
1119 * address, we assume we followed a broken pointer during an indirect call, so
1120 * we try the lookup again with the return address pushed on the stack
1122 if (!ji && fault_addr == (gpointer)UCONTEXT_REG_EIP (ctx)) {
1123 glong *sp = (gpointer)UCONTEXT_REG_ESP (ctx);
1124 ji = mini_jit_info_table_find (mono_domain_get (), (gpointer)sp [0], NULL);
1126 UCONTEXT_REG_EIP (ctx) = sp [0];
1129 exc = mono_domain_get ()->stack_overflow_ex;
1131 mono_handle_native_sigsegv (SIGSEGV, sigctx);
1132 /* setup a call frame on the real stack so that control is returned there
1133 * and exception handling can continue.
1134 * If this was a stack overflow the caller already ensured the stack pages
1135 * needed have been unprotected.
1136 * The frame looks like:
1143 // FIXME: test_only is no more.
1144 frame_size = sizeof (MonoContext) + sizeof (gpointer) * 4;
1147 sp = (gpointer)(UCONTEXT_REG_ESP (ctx) & ~15);
1148 sp = (gpointer)((char*)sp - frame_size);
1149 /* the incoming arguments are aligned to 16 bytes boundaries, so the return address IP
1152 sp [-1] = (gpointer)UCONTEXT_REG_EIP (ctx);
1155 sp [2] = (gpointer)stack_ovf;
1156 mono_sigctx_to_monoctx (sigctx, (MonoContext*)(sp + 4));
1157 /* at the return form the signal handler execution starts in altstack_handle_and_restore() */
1158 UCONTEXT_REG_EIP (ctx) = (unsigned long)altstack_handle_and_restore;
1159 UCONTEXT_REG_ESP (ctx) = (unsigned long)(sp - 1);
1163 #if MONO_SUPPORT_TASKLETS
1164 MonoContinuationRestore
1165 mono_tasklets_arch_restore (void)
1167 static guint8* saved = NULL;
1168 guint8 *code, *start;
1170 #ifdef __native_client_codegen__
1171 g_print("mono_tasklets_arch_restore needs to be aligned for Native Client\n");
1174 return (MonoContinuationRestore)saved;
1175 code = start = mono_global_codeman_reserve (48);
1176 /* the signature is: restore (MonoContinuation *cont, int state, MonoLMF **lmf_addr) */
1177 /* put cont in edx */
1178 x86_mov_reg_membase (code, X86_EDX, X86_ESP, 4, 4);
1179 /* state in eax, so it's setup as the return value */
1180 x86_mov_reg_membase (code, X86_EAX, X86_ESP, 8, 4);
1182 /* setup the copy of the stack */
1183 x86_mov_reg_membase (code, X86_ECX, X86_EDX, MONO_STRUCT_OFFSET (MonoContinuation, stack_used_size), 4);
1184 x86_shift_reg_imm (code, X86_SHR, X86_ECX, 2);
1186 x86_mov_reg_membase (code, X86_ESI, X86_EDX, MONO_STRUCT_OFFSET (MonoContinuation, saved_stack), 4);
1187 x86_mov_reg_membase (code, X86_EDI, X86_EDX, MONO_STRUCT_OFFSET (MonoContinuation, return_sp), 4);
1188 x86_prefix (code, X86_REP_PREFIX);
1191 /* now restore the registers from the LMF */
1192 x86_mov_reg_membase (code, X86_ECX, X86_EDX, MONO_STRUCT_OFFSET (MonoContinuation, lmf), 4);
1193 x86_mov_reg_membase (code, X86_EBX, X86_ECX, MONO_STRUCT_OFFSET (MonoLMF, ebx), 4);
1194 x86_mov_reg_membase (code, X86_EBP, X86_ECX, MONO_STRUCT_OFFSET (MonoLMF, ebp), 4);
1195 x86_mov_reg_membase (code, X86_ESI, X86_ECX, MONO_STRUCT_OFFSET (MonoLMF, esi), 4);
1196 x86_mov_reg_membase (code, X86_EDI, X86_ECX, MONO_STRUCT_OFFSET (MonoLMF, edi), 4);
1198 /* restore the lmf chain */
1199 /*x86_mov_reg_membase (code, X86_ECX, X86_ESP, 12, 4);
1200 x86_mov_membase_reg (code, X86_ECX, 0, X86_EDX, 4);*/
1202 x86_jump_membase (code, X86_EDX, MONO_STRUCT_OFFSET (MonoContinuation, return_ip));
1203 g_assert ((code - start) <= 48);
1205 return (MonoContinuationRestore)saved;
1210 * mono_arch_setup_resume_sighandler_ctx:
1212 * Setup CTX so execution continues at FUNC.
1215 mono_arch_setup_resume_sighandler_ctx (MonoContext *ctx, gpointer func)
1217 int align = (((gint32)MONO_CONTEXT_GET_SP (ctx)) % MONO_ARCH_FRAME_ALIGNMENT + 4);
1220 MONO_CONTEXT_SET_SP (ctx, (gsize)MONO_CONTEXT_GET_SP (ctx) - align);
1222 MONO_CONTEXT_SET_IP (ctx, func);