3 * exception support for x86
6 * Dietmar Maurer (dietmar@ximian.com)
8 * (C) 2001 Ximian, Inc.
16 #ifdef HAVE_UCONTEXT_H
20 #include <mono/metadata/abi-details.h>
21 #include <mono/arch/x86/x86-codegen.h>
22 #include <mono/metadata/appdomain.h>
23 #include <mono/metadata/tabledefs.h>
24 #include <mono/metadata/threads.h>
25 #include <mono/metadata/debug-helpers.h>
26 #include <mono/metadata/exception.h>
27 #include <mono/metadata/gc-internals.h>
28 #include <mono/metadata/mono-debug.h>
29 #include <mono/utils/mono-mmap.h>
35 static gpointer signal_exception_trampoline
;
38 mono_x86_get_signal_exception_trampoline (MonoTrampInfo
**info
, gboolean aot
);
41 static void (*restore_stack
) (void *);
43 static MonoW32ExceptionHandler fpe_handler
;
44 static MonoW32ExceptionHandler ill_handler
;
45 static MonoW32ExceptionHandler segv_handler
;
47 LPTOP_LEVEL_EXCEPTION_FILTER mono_old_win_toplevel_exception_filter
;
48 gpointer mono_win_vectored_exception_handle
;
49 extern int (*gUnhandledExceptionHandler
)(EXCEPTION_POINTERS
*);
51 #ifndef PROCESS_CALLBACK_FILTER_ENABLED
52 # define PROCESS_CALLBACK_FILTER_ENABLED 1
55 #define W32_SEH_HANDLE_EX(_ex) \
56 if (_ex##_handler) _ex##_handler(0, ep, ctx)
58 LONG CALLBACK
seh_unhandled_exception_filter(EXCEPTION_POINTERS
* ep
)
60 #ifndef MONO_CROSS_COMPILE
61 if (mono_old_win_toplevel_exception_filter
) {
62 return (*mono_old_win_toplevel_exception_filter
)(ep
);
66 mono_handle_native_crash ("SIGSEGV", NULL
, NULL
);
68 return EXCEPTION_CONTINUE_SEARCH
;
72 * mono_win32_get_handle_stackoverflow (void):
74 * Returns a pointer to a method which restores the current context stack
75 * and calls handle_exceptions, when done restores the original stack.
78 mono_win32_get_handle_stackoverflow (void)
80 static guint8
*start
= NULL
;
86 /* restore_contect (void *sigctx) */
87 start
= code
= mono_global_codeman_reserve (128);
89 /* load context into ebx */
90 x86_mov_reg_membase (code
, X86_EBX
, X86_ESP
, 4, 4);
92 /* move current stack into edi for later restore */
93 x86_mov_reg_reg (code
, X86_EDI
, X86_ESP
, 4);
95 /* use the new freed stack from sigcontext */
96 /* XXX replace usage of struct sigcontext with MonoContext so we can use MONO_STRUCT_OFFSET */
97 x86_mov_reg_membase (code
, X86_ESP
, X86_EBX
, G_STRUCT_OFFSET (struct sigcontext
, esp
), 4);
99 /* get the current domain */
100 x86_call_code (code
, mono_domain_get
);
102 /* get stack overflow exception from domain object */
103 x86_mov_reg_membase (code
, X86_EAX
, X86_EAX
, G_STRUCT_OFFSET (MonoDomain
, stack_overflow_ex
), 4);
105 /* call mono_arch_handle_exception (sctx, stack_overflow_exception_obj) */
106 x86_push_reg (code
, X86_EAX
);
107 x86_push_reg (code
, X86_EBX
);
108 x86_call_code (code
, mono_arch_handle_exception
);
110 /* restore the SEH handler stack */
111 x86_mov_reg_reg (code
, X86_ESP
, X86_EDI
, 4);
116 mono_arch_flush_icache (start
, code
- start
);
117 MONO_PROFILER_RAISE (jit_code_buffer
, (start
, code
- start
, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING
, NULL
));
122 /* Special hack to workaround the fact that the
123 * when the SEH handler is called the stack is
124 * to small to recover.
126 * Stack walking part of this method is from mono_handle_exception
128 * The idea is simple;
129 * - walk the stack to free some space (64k)
130 * - set esp to new stack location
131 * - call mono_arch_handle_exception with stack overflow exception
132 * - set esp to SEH handlers stack
136 win32_handle_stack_overflow (EXCEPTION_POINTERS
* ep
, struct sigcontext
*sctx
)
140 MonoDomain
*domain
= mono_domain_get ();
142 MonoJitTlsData
*jit_tls
= mono_tls_get_jit_tls ();
143 MonoLMF
*lmf
= jit_tls
->lmf
;
144 MonoContext initial_ctx
;
146 guint32 free_stack
= 0;
147 StackFrameInfo frame
;
149 mono_sigctx_to_monoctx (sctx
, &ctx
);
151 /* get our os page size */
153 page_size
= si
.dwPageSize
;
155 /* Let's walk the stack to recover
156 * the needed stack space (if possible)
158 memset (&rji
, 0, sizeof (rji
));
161 free_stack
= (guint8
*)(MONO_CONTEXT_GET_BP (&ctx
)) - (guint8
*)(MONO_CONTEXT_GET_BP (&initial_ctx
));
163 /* try to free 64kb from our stack */
167 mono_arch_unwind_frame (domain
, jit_tls
, &rji
, &ctx
, &new_ctx
, &lmf
, NULL
, &frame
);
169 g_warning ("Exception inside function without unwind info");
170 g_assert_not_reached ();
173 if (frame
.ji
!= (gpointer
)-1) {
174 free_stack
= (guint8
*)(MONO_CONTEXT_GET_BP (&ctx
)) - (guint8
*)(MONO_CONTEXT_GET_BP (&initial_ctx
));
177 /* todo: we should call abort if ji is -1 */
179 } while (free_stack
< 64 * 1024 && frame
.ji
!= (gpointer
) -1);
181 mono_monoctx_to_sigctx (&ctx
, sctx
);
183 /* todo: install new stack-guard page */
185 /* use the new stack and call mono_arch_handle_exception () */
186 restore_stack (sctx
);
190 * Unhandled Exception Filter
191 * Top-level per-process exception handler.
193 LONG CALLBACK
seh_vectored_exception_handler(EXCEPTION_POINTERS
* ep
)
195 EXCEPTION_RECORD
* er
;
198 MonoJitTlsData
*jit_tls
= mono_tls_get_jit_tls ();
200 /* If the thread is not managed by the runtime return early */
202 return EXCEPTION_CONTINUE_SEARCH
;
204 jit_tls
->mono_win_chained_exception_needs_run
= FALSE
;
205 res
= EXCEPTION_CONTINUE_EXECUTION
;
207 er
= ep
->ExceptionRecord
;
208 ctx
= ep
->ContextRecord
;
210 switch (er
->ExceptionCode
) {
211 case EXCEPTION_STACK_OVERFLOW
:
212 win32_handle_stack_overflow (ep
, ctx
);
214 case EXCEPTION_ACCESS_VIOLATION
:
215 W32_SEH_HANDLE_EX(segv
);
217 case EXCEPTION_ILLEGAL_INSTRUCTION
:
218 W32_SEH_HANDLE_EX(ill
);
220 case EXCEPTION_INT_DIVIDE_BY_ZERO
:
221 case EXCEPTION_INT_OVERFLOW
:
222 case EXCEPTION_FLT_DIVIDE_BY_ZERO
:
223 case EXCEPTION_FLT_OVERFLOW
:
224 case EXCEPTION_FLT_UNDERFLOW
:
225 case EXCEPTION_FLT_INEXACT_RESULT
:
226 W32_SEH_HANDLE_EX(fpe
);
229 jit_tls
->mono_win_chained_exception_needs_run
= TRUE
;
233 if (jit_tls
->mono_win_chained_exception_needs_run
) {
234 /* Don't copy context back if we chained exception
235 * as the handler may have modfied the EXCEPTION_POINTERS
236 * directly. We don't pass sigcontext to chained handlers.
237 * Return continue search so the UnhandledExceptionFilter
238 * can correctly chain the exception.
240 res
= EXCEPTION_CONTINUE_SEARCH
;
246 void win32_seh_init()
248 /* install restore stack helper */
250 restore_stack
= mono_win32_get_handle_stackoverflow ();
252 mono_old_win_toplevel_exception_filter
= SetUnhandledExceptionFilter(seh_unhandled_exception_filter
);
253 mono_win_vectored_exception_handle
= AddVectoredExceptionHandler (1, seh_vectored_exception_handler
);
256 void win32_seh_cleanup()
258 if (mono_old_win_toplevel_exception_filter
)
259 SetUnhandledExceptionFilter(mono_old_win_toplevel_exception_filter
);
260 RemoveVectoredExceptionHandler (mono_win_vectored_exception_handle
);
263 void win32_seh_set_handler(int type
, MonoW32ExceptionHandler handler
)
267 fpe_handler
= handler
;
270 ill_handler
= handler
;
273 segv_handler
= handler
;
280 #endif /* TARGET_WIN32 */
283 * mono_arch_get_restore_context:
285 * Returns a pointer to a method which restores a previously saved sigcontext.
288 mono_arch_get_restore_context (MonoTrampInfo
**info
, gboolean aot
)
290 guint8
*start
= NULL
;
292 MonoJumpInfo
*ji
= NULL
;
293 GSList
*unwind_ops
= NULL
;
295 /* restore_contect (MonoContext *ctx) */
297 start
= code
= mono_global_codeman_reserve (128);
300 x86_mov_reg_membase (code
, X86_EAX
, X86_ESP
, 4, 4);
303 x86_mov_reg_membase (code
, X86_EBX
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, ebx
), 4);
306 x86_mov_reg_membase (code
, X86_EDI
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, edi
), 4);
309 x86_mov_reg_membase (code
, X86_ESI
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, esi
), 4);
312 x86_mov_reg_membase (code
, X86_EDX
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, edx
), 4);
315 * The context resides on the stack, in the stack frame of the
316 * caller of this function. The stack pointer that we need to
317 * restore is potentially many stack frames higher up, so the
318 * distance between them can easily be more than the red zone
319 * size. Hence the stack pointer can be restored only after
320 * we have finished loading everything from the context.
323 /* load ESP into EBP */
324 x86_mov_reg_membase (code
, X86_EBP
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, esp
), 4);
325 /* load return address into ECX */
326 x86_mov_reg_membase (code
, X86_ECX
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, eip
), 4);
327 /* save the return addr to the restored stack - 4 */
328 x86_mov_membase_reg (code
, X86_EBP
, -4, X86_ECX
, 4);
330 /* load EBP into ECX */
331 x86_mov_reg_membase (code
, X86_ECX
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, ebp
), 4);
332 /* save EBP to the restored stack - 8 */
333 x86_mov_membase_reg (code
, X86_EBP
, -8, X86_ECX
, 4);
335 /* load EAX into ECX */
336 x86_mov_reg_membase (code
, X86_ECX
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, eax
), 4);
337 /* save EAX to the restored stack - 12 */
338 x86_mov_membase_reg (code
, X86_EBP
, -12, X86_ECX
, 4);
341 x86_mov_reg_membase (code
, X86_ECX
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, ecx
), 4);
343 /* restore ESP - 12 */
344 x86_lea_membase (code
, X86_ESP
, X86_EBP
, -12);
346 x86_pop_reg (code
, X86_EAX
);
348 x86_pop_reg (code
, X86_EBP
);
349 /* jump to the saved IP */
353 *info
= mono_tramp_info_create ("restore_context", start
, code
- start
, ji
, unwind_ops
);
357 for (l
= unwind_ops
; l
; l
= l
->next
)
359 g_slist_free (unwind_ops
);
362 mono_arch_flush_icache (start
, code
- start
);
363 MONO_PROFILER_RAISE (jit_code_buffer
, (start
, code
- start
, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING
, NULL
));
369 * mono_arch_get_call_filter:
371 * Returns a pointer to a method which calls an exception filter. We
372 * also use this function to call finally handlers (we pass NULL as
373 * @exc object in this case).
376 mono_arch_get_call_filter (MonoTrampInfo
**info
, gboolean aot
)
380 MonoJumpInfo
*ji
= NULL
;
381 GSList
*unwind_ops
= NULL
;
382 guint kMaxCodeSize
= 64;
384 /* call_filter (MonoContext *ctx, unsigned long eip) */
385 start
= code
= mono_global_codeman_reserve (kMaxCodeSize
);
387 x86_push_reg (code
, X86_EBP
);
388 x86_mov_reg_reg (code
, X86_EBP
, X86_ESP
, 4);
389 x86_push_reg (code
, X86_EBX
);
390 x86_push_reg (code
, X86_EDI
);
391 x86_push_reg (code
, X86_ESI
);
394 x86_mov_reg_membase (code
, X86_EAX
, X86_EBP
, 8, 4);
396 x86_mov_reg_membase (code
, X86_ECX
, X86_EBP
, 12, 4);
398 x86_push_reg (code
, X86_EBP
);
401 x86_mov_reg_membase (code
, X86_EBP
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, ebp
), 4);
402 /* restore registers used by global register allocation (EBX & ESI) */
403 x86_mov_reg_membase (code
, X86_EBX
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, ebx
), 4);
404 x86_mov_reg_membase (code
, X86_ESI
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, esi
), 4);
405 x86_mov_reg_membase (code
, X86_EDI
, X86_EAX
, MONO_STRUCT_OFFSET (MonoContext
, edi
), 4);
407 /* align stack and save ESP */
408 x86_mov_reg_reg (code
, X86_EDX
, X86_ESP
, 4);
409 x86_alu_reg_imm (code
, X86_AND
, X86_ESP
, -MONO_ARCH_FRAME_ALIGNMENT
);
410 g_assert (MONO_ARCH_FRAME_ALIGNMENT
>= 8);
411 x86_alu_reg_imm (code
, X86_SUB
, X86_ESP
, MONO_ARCH_FRAME_ALIGNMENT
- 8);
412 x86_push_reg (code
, X86_EDX
);
414 /* call the handler */
415 x86_call_reg (code
, X86_ECX
);
418 x86_pop_reg (code
, X86_ESP
);
421 x86_pop_reg (code
, X86_EBP
);
423 /* restore saved regs */
424 x86_pop_reg (code
, X86_ESI
);
425 x86_pop_reg (code
, X86_EDI
);
426 x86_pop_reg (code
, X86_EBX
);
431 *info
= mono_tramp_info_create ("call_filter", start
, code
- start
, ji
, unwind_ops
);
435 for (l
= unwind_ops
; l
; l
= l
->next
)
437 g_slist_free (unwind_ops
);
440 mono_arch_flush_icache (start
, code
- start
);
441 MONO_PROFILER_RAISE (jit_code_buffer
, (start
, code
- start
, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING
, NULL
));
443 g_assert ((code
- start
) < kMaxCodeSize
);
448 * mono_x86_throw_exception:
450 * C function called from the throw trampolines.
453 mono_x86_throw_exception (mgreg_t
*regs
, MonoObject
*exc
,
454 mgreg_t eip
, gboolean rethrow
)
459 ctx
.esp
= regs
[X86_ESP
];
461 ctx
.ebp
= regs
[X86_EBP
];
462 ctx
.edi
= regs
[X86_EDI
];
463 ctx
.esi
= regs
[X86_ESI
];
464 ctx
.ebx
= regs
[X86_EBX
];
465 ctx
.edx
= regs
[X86_EDX
];
466 ctx
.ecx
= regs
[X86_ECX
];
467 ctx
.eax
= regs
[X86_EAX
];
470 /* The OSX ABI specifies 16 byte alignment at call sites */
471 g_assert ((ctx
.esp
% MONO_ARCH_FRAME_ALIGNMENT
) == 0);
474 if (mono_object_isinst_checked (exc
, mono_defaults
.exception_class
, &error
)) {
475 MonoException
*mono_ex
= (MonoException
*)exc
;
477 mono_ex
->stack_trace
= NULL
;
478 mono_ex
->trace_ips
= NULL
;
481 mono_error_assert_ok (&error
);
483 /* adjust eip so that it point into the call instruction */
486 mono_handle_exception (&ctx
, exc
);
488 mono_restore_context (&ctx
);
490 g_assert_not_reached ();
494 mono_x86_throw_corlib_exception (mgreg_t
*regs
, guint32 ex_token_index
,
495 mgreg_t eip
, gint32 pc_offset
)
497 guint32 ex_token
= MONO_TOKEN_TYPE_DEF
| ex_token_index
;
500 ex
= mono_exception_from_token (mono_defaults
.exception_class
->image
, ex_token
);
504 /* Negate the ip adjustment done in mono_x86_throw_exception () */
507 mono_x86_throw_exception (regs
, (MonoObject
*)ex
, eip
, FALSE
);
511 mono_x86_resume_unwind (mgreg_t
*regs
, MonoObject
*exc
,
512 mgreg_t eip
, gboolean rethrow
)
516 ctx
.esp
= regs
[X86_ESP
];
518 ctx
.ebp
= regs
[X86_EBP
];
519 ctx
.edi
= regs
[X86_EDI
];
520 ctx
.esi
= regs
[X86_ESI
];
521 ctx
.ebx
= regs
[X86_EBX
];
522 ctx
.edx
= regs
[X86_EDX
];
523 ctx
.ecx
= regs
[X86_ECX
];
524 ctx
.eax
= regs
[X86_EAX
];
526 mono_resume_unwind (&ctx
);
530 * get_throw_trampoline:
532 * Generate a call to mono_x86_throw_exception/
533 * mono_x86_throw_corlib_exception.
534 * If LLVM is true, generate code which assumes the caller is LLVM generated code,
535 * which doesn't push the arguments.
538 get_throw_trampoline (const char *name
, gboolean rethrow
, gboolean llvm
, gboolean corlib
, gboolean llvm_abs
, gboolean resume_unwind
, MonoTrampInfo
**info
, gboolean aot
)
540 guint8
*start
, *code
, *labels
[16];
541 int i
, stack_size
, stack_offset
, arg_offsets
[5], regs_offset
;
542 MonoJumpInfo
*ji
= NULL
;
543 GSList
*unwind_ops
= NULL
;
544 guint kMaxCodeSize
= 192;
546 start
= code
= mono_global_codeman_reserve (kMaxCodeSize
);
551 * On apple, the stack is misaligned by the pushing of the return address.
554 /* On OSX, we don't generate alignment code to save space */
557 stack_size
+= MONO_ARCH_FRAME_ALIGNMENT
- 4;
560 * The stack looks like this:
561 * <pc offset> (only if corlib is TRUE)
562 * <exception object>/<type token>
563 * <return addr> <- esp (unaligned on apple)
566 unwind_ops
= mono_arch_get_cie_program ();
569 x86_alu_reg_imm (code
, X86_SUB
, X86_ESP
, stack_size
);
570 mono_add_unwind_op_def_cfa_offset (unwind_ops
, code
, start
, stack_size
+ 4);
575 arg_offsets
[3] = 12;
579 for (i
= 0; i
< X86_NREG
; ++i
)
581 x86_mov_membase_reg (code
, X86_ESP
, regs_offset
+ (i
* 4), i
, 4);
582 /* Calculate the offset between the current sp and the sp of the caller */
584 /* LLVM doesn't push the arguments */
585 stack_offset
= stack_size
+ 4;
589 stack_offset
= stack_size
+ 4 + 8;
591 /* We don't generate stack alignment code on osx to save space */
594 /* One argument + stack alignment */
595 stack_offset
= stack_size
+ 4 + 4;
597 /* Pop the alignment added by OP_THROW too */
598 stack_offset
+= MONO_ARCH_FRAME_ALIGNMENT
- 4;
600 if (mono_do_x86_stack_align
)
601 stack_offset
+= MONO_ARCH_FRAME_ALIGNMENT
- 4;
606 x86_lea_membase (code
, X86_EAX
, X86_ESP
, stack_offset
);
607 x86_mov_membase_reg (code
, X86_ESP
, regs_offset
+ (X86_ESP
* 4), X86_EAX
, 4);
612 x86_shift_reg_imm (code
, X86_SHR
, X86_EAX
, 11);
613 x86_alu_reg_imm (code
, X86_AND
, X86_EAX
, 7);
614 x86_alu_reg_imm (code
, X86_CMP
, X86_EAX
, 0);
616 x86_branch8 (code
, X86_CC_EQ
, 0, FALSE
);
618 x86_jump_code (code
, labels
[0]);
619 mono_x86_patch (labels
[1], code
);
621 /* Set arg1 == regs */
622 x86_lea_membase (code
, X86_EAX
, X86_ESP
, regs_offset
);
623 x86_mov_membase_reg (code
, X86_ESP
, arg_offsets
[0], X86_EAX
, 4);
624 /* Set arg2 == exc/ex_token_index */
626 x86_mov_reg_imm (code
, X86_EAX
, 0);
628 x86_mov_reg_membase (code
, X86_EAX
, X86_ESP
, stack_size
+ 4, 4);
629 x86_mov_membase_reg (code
, X86_ESP
, arg_offsets
[1], X86_EAX
, 4);
630 /* Set arg3 == eip */
632 x86_alu_reg_reg (code
, X86_XOR
, X86_EAX
, X86_EAX
);
634 x86_mov_reg_membase (code
, X86_EAX
, X86_ESP
, stack_size
, 4);
635 x86_mov_membase_reg (code
, X86_ESP
, arg_offsets
[2], X86_EAX
, 4);
636 /* Set arg4 == rethrow/pc_offset */
638 x86_mov_membase_imm (code
, X86_ESP
, arg_offsets
[3], 0, 4);
640 x86_mov_reg_membase (code
, X86_EAX
, X86_ESP
, stack_size
+ 8, 4);
643 * The caller is LLVM code which passes the absolute address not a pc offset,
644 * so compensate by passing 0 as 'ip' and passing the negated abs address as
647 x86_neg_reg (code
, X86_EAX
);
649 x86_mov_membase_reg (code
, X86_ESP
, arg_offsets
[3], X86_EAX
, 4);
651 x86_mov_membase_imm (code
, X86_ESP
, arg_offsets
[3], rethrow
, 4);
655 // This can be called from runtime code, which can't guarantee that
656 // ebx contains the got address.
657 // So emit the got address loading code too
658 code
= mono_arch_emit_load_got_addr (start
, code
, NULL
, &ji
);
659 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");
660 x86_call_reg (code
, X86_EAX
);
662 x86_call_code (code
, resume_unwind
? (gpointer
)(mono_x86_resume_unwind
) : (corlib
? (gpointer
)mono_x86_throw_corlib_exception
: (gpointer
)mono_x86_throw_exception
));
664 x86_breakpoint (code
);
666 g_assert ((code
- start
) < kMaxCodeSize
);
669 *info
= mono_tramp_info_create (name
, start
, code
- start
, ji
, unwind_ops
);
673 for (l
= unwind_ops
; l
; l
= l
->next
)
675 g_slist_free (unwind_ops
);
678 mono_arch_flush_icache (start
, code
- start
);
679 MONO_PROFILER_RAISE (jit_code_buffer
, (start
, code
- start
, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING
, NULL
));
685 * mono_arch_get_throw_exception:
686 * \returns a function pointer which can be used to raise
687 * exceptions. The returned function has the following
688 * signature: void (*func) (MonoException *exc);
689 * For example to raise an arithmetic exception you can use:
691 * x86_push_imm (code, mono_get_exception_arithmetic ());
692 * x86_call_code (code, arch_get_throw_exception ());
696 mono_arch_get_throw_exception (MonoTrampInfo
**info
, gboolean aot
)
698 return get_throw_trampoline ("throw_exception", FALSE
, FALSE
, FALSE
, FALSE
, FALSE
, info
, aot
);
702 mono_arch_get_rethrow_exception (MonoTrampInfo
**info
, gboolean aot
)
704 return get_throw_trampoline ("rethrow_exception", TRUE
, FALSE
, FALSE
, FALSE
, FALSE
, info
, aot
);
708 * mono_arch_get_throw_corlib_exception:
709 * \returns a function pointer which can be used to raise
710 * corlib exceptions. The returned function has the following
711 * signature: void (*func) (guint32 ex_token, guint32 offset);
712 * Here, offset is the offset which needs to be substracted from the caller IP
713 * to get the IP of the throw. Passing the offset has the advantage that it
714 * needs no relocations in the caller.
717 mono_arch_get_throw_corlib_exception (MonoTrampInfo
**info
, gboolean aot
)
719 return get_throw_trampoline ("throw_corlib_exception", FALSE
, FALSE
, TRUE
, FALSE
, FALSE
, info
, aot
);
723 mono_arch_exceptions_init (void)
726 MonoTrampInfo
*tinfo
;
729 * If we're running WoW64, we need to set the usermode exception policy
730 * for SEHs to behave. This requires hotfix http://support.microsoft.com/kb/976038
731 * or (eventually) Windows 7 SP1.
737 HMODULE kernel32
= LoadLibraryW (L
"kernel32.dll");
740 getter
= GetProcAddress (kernel32
, "GetProcessUserModeExceptionPolicy");
741 setter
= GetProcAddress (kernel32
, "SetProcessUserModeExceptionPolicy");
742 if (getter
&& setter
) {
744 setter (flags
& ~PROCESS_CALLBACK_FILTER_ENABLED
);
750 signal_exception_trampoline
= mono_aot_get_trampoline ("x86_signal_exception_trampoline");
754 /* LLVM needs different throw trampolines */
755 tramp
= get_throw_trampoline ("llvm_throw_exception_trampoline", FALSE
, TRUE
, FALSE
, FALSE
, FALSE
, &tinfo
, FALSE
);
756 mono_register_jit_icall (tramp
, "llvm_throw_exception_trampoline", NULL
, TRUE
);
757 mono_tramp_info_register (tinfo
, NULL
);
759 tramp
= get_throw_trampoline ("llvm_rethrow_exception_trampoline", TRUE
, TRUE
, FALSE
, FALSE
, FALSE
, &tinfo
, FALSE
);
760 mono_register_jit_icall (tramp
, "llvm_rethrow_exception_trampoline", NULL
, TRUE
);
761 mono_tramp_info_register (tinfo
, NULL
);
763 tramp
= get_throw_trampoline ("llvm_throw_corlib_exception_trampoline", FALSE
, TRUE
, TRUE
, FALSE
, FALSE
, &tinfo
, FALSE
);
764 mono_register_jit_icall (tramp
, "llvm_throw_corlib_exception_trampoline", NULL
, TRUE
);
765 mono_tramp_info_register (tinfo
, NULL
);
767 tramp
= get_throw_trampoline ("llvm_throw_corlib_exception_abs_trampoline", FALSE
, TRUE
, TRUE
, TRUE
, FALSE
, &tinfo
, FALSE
);
768 mono_register_jit_icall (tramp
, "llvm_throw_corlib_exception_abs_trampoline", NULL
, TRUE
);
769 mono_tramp_info_register (tinfo
, NULL
);
771 tramp
= get_throw_trampoline ("llvm_resume_unwind_trampoline", FALSE
, FALSE
, FALSE
, FALSE
, TRUE
, &tinfo
, FALSE
);
772 mono_register_jit_icall (tramp
, "llvm_resume_unwind_trampoline", NULL
, TRUE
);
773 mono_tramp_info_register (tinfo
, NULL
);
775 signal_exception_trampoline
= mono_x86_get_signal_exception_trampoline (&tinfo
, FALSE
);
776 mono_tramp_info_register (tinfo
, NULL
);
780 * mono_arch_unwind_frame:
782 * See exceptions-amd64.c for docs.
785 mono_arch_unwind_frame (MonoDomain
*domain
, MonoJitTlsData
*jit_tls
,
786 MonoJitInfo
*ji
, MonoContext
*ctx
,
787 MonoContext
*new_ctx
, MonoLMF
**lmf
,
788 mgreg_t
**save_locations
,
789 StackFrameInfo
*frame
)
791 gpointer ip
= MONO_CONTEXT_GET_IP (ctx
);
793 memset (frame
, 0, sizeof (StackFrameInfo
));
799 gssize regs
[MONO_MAX_IREGS
+ 1];
801 guint32 unwind_info_len
;
804 if (ji
->is_trampoline
)
805 frame
->type
= FRAME_TYPE_TRAMPOLINE
;
807 frame
->type
= FRAME_TYPE_MANAGED
;
809 unwind_info
= mono_jinfo_get_unwind_info (ji
, &unwind_info_len
);
811 regs
[X86_EAX
] = new_ctx
->eax
;
812 regs
[X86_EBX
] = new_ctx
->ebx
;
813 regs
[X86_ECX
] = new_ctx
->ecx
;
814 regs
[X86_EDX
] = new_ctx
->edx
;
815 regs
[X86_ESP
] = new_ctx
->esp
;
816 regs
[X86_EBP
] = new_ctx
->ebp
;
817 regs
[X86_ESI
] = new_ctx
->esi
;
818 regs
[X86_EDI
] = new_ctx
->edi
;
819 regs
[X86_NREG
] = new_ctx
->eip
;
821 mono_unwind_frame (unwind_info
, unwind_info_len
, ji
->code_start
,
822 (guint8
*)ji
->code_start
+ ji
->code_size
,
823 ip
, NULL
, regs
, MONO_MAX_IREGS
+ 1,
824 save_locations
, MONO_MAX_IREGS
, &cfa
);
826 new_ctx
->eax
= regs
[X86_EAX
];
827 new_ctx
->ebx
= regs
[X86_EBX
];
828 new_ctx
->ecx
= regs
[X86_ECX
];
829 new_ctx
->edx
= regs
[X86_EDX
];
830 new_ctx
->esp
= regs
[X86_ESP
];
831 new_ctx
->ebp
= regs
[X86_EBP
];
832 new_ctx
->esi
= regs
[X86_ESI
];
833 new_ctx
->edi
= regs
[X86_EDI
];
834 new_ctx
->eip
= regs
[X86_NREG
];
836 /* The CFA becomes the new SP value */
837 new_ctx
->esp
= (gssize
)cfa
;
845 if (((guint64
)(*lmf
)->previous_lmf
) & 2) {
847 * This LMF entry is created by the soft debug code to mark transitions to
848 * managed code done during invokes.
850 MonoLMFExt
*ext
= (MonoLMFExt
*)(*lmf
);
852 g_assert (ext
->debugger_invoke
);
854 memcpy (new_ctx
, &ext
->ctx
, sizeof (MonoContext
));
856 *lmf
= (gpointer
)(((gsize
)(*lmf
)->previous_lmf
) & ~3);
858 frame
->type
= FRAME_TYPE_DEBUGGER_INVOKE
;
863 if ((ji
= mini_jit_info_table_find (domain
, (gpointer
)(*lmf
)->eip
, NULL
))) {
868 frame
->method
= (*lmf
)->method
;
871 new_ctx
->esi
= (*lmf
)->esi
;
872 new_ctx
->edi
= (*lmf
)->edi
;
873 new_ctx
->ebx
= (*lmf
)->ebx
;
874 new_ctx
->ebp
= (*lmf
)->ebp
;
875 new_ctx
->eip
= (*lmf
)->eip
;
880 frame
->type
= FRAME_TYPE_MANAGED_TO_NATIVE
;
882 /* Check if we are in a trampoline LMF frame */
883 if ((guint32
)((*lmf
)->previous_lmf
) & 1) {
884 /* lmf->esp is set by the trampoline code */
885 new_ctx
->esp
= (*lmf
)->esp
;
888 /* the lmf is always stored on the stack, so the following
889 * expression points to a stack location which can be used as ESP */
890 new_ctx
->esp
= (unsigned long)&((*lmf
)->eip
);
892 *lmf
= (gpointer
)(((gsize
)(*lmf
)->previous_lmf
) & ~3);
901 mono_arch_ip_from_context (void *sigctx
)
903 #if defined(HOST_WATCHOS)
904 printf("WARNING: mono_arch_ip_from_context() called!\n");
906 #elif defined(MONO_ARCH_USE_SIGACTION)
907 ucontext_t
*ctx
= (ucontext_t
*)sigctx
;
908 return (gpointer
)UCONTEXT_REG_EIP (ctx
);
909 #elif defined(HOST_WIN32)
910 return ((CONTEXT
*)sigctx
)->Eip
;
912 struct sigcontext
*ctx
= sigctx
;
913 return (gpointer
)ctx
->SC_EIP
;
920 * Called by resuming from a signal handler.
923 handle_signal_exception (gpointer obj
)
925 MonoJitTlsData
*jit_tls
= mono_tls_get_jit_tls ();
928 memcpy (&ctx
, &jit_tls
->ex_ctx
, sizeof (MonoContext
));
930 mono_handle_exception (&ctx
, obj
);
932 mono_restore_context (&ctx
);
936 * mono_x86_get_signal_exception_trampoline:
938 * This x86 specific trampoline is used to call handle_signal_exception.
941 mono_x86_get_signal_exception_trampoline (MonoTrampInfo
**info
, gboolean aot
)
943 guint8
*start
, *code
;
944 MonoJumpInfo
*ji
= NULL
;
945 GSList
*unwind_ops
= NULL
;
948 start
= code
= mono_global_codeman_reserve (128);
950 /* FIXME no unwind before we push ip */
952 x86_push_reg (code
, X86_ECX
);
954 mono_add_unwind_op_def_cfa (unwind_ops
, code
, start
, X86_ESP
, 4);
955 mono_add_unwind_op_offset (unwind_ops
, code
, start
, X86_NREG
, -4);
957 /* Fix the alignment to be what apple expects */
960 x86_alu_reg_imm (code
, X86_SUB
, X86_ESP
, stack_size
);
961 mono_add_unwind_op_def_cfa_offset (unwind_ops
, code
, start
, stack_size
+ 4);
964 x86_mov_membase_reg (code
, X86_ESP
, 0, X86_EAX
, 4);
965 /* Branch to target */
966 x86_call_reg (code
, X86_EDX
);
968 g_assert ((code
- start
) < 128);
971 *info
= mono_tramp_info_create ("x86_signal_exception_trampoline", start
, code
- start
, ji
, unwind_ops
);
975 for (l
= unwind_ops
; l
; l
= l
->next
)
977 g_slist_free (unwind_ops
);
980 mono_arch_flush_icache (start
, code
- start
);
981 MONO_PROFILER_RAISE (jit_code_buffer
, (start
, code
- start
, MONO_PROFILER_CODE_BUFFER_EXCEPTION_HANDLING
, NULL
));
988 mono_arch_setup_async_callback (MonoContext
*ctx
, void (*async_cb
)(void *fun
), gpointer user_data
)
991 * Can't pass the obj on the stack, since we are executing on the
992 * same stack. Can't save it into MonoJitTlsData, since it needs GC tracking.
993 * So put it into a register, and branch to a trampoline which
996 ctx
->eax
= (mgreg_t
)user_data
;
998 ctx
->edx
= (mgreg_t
)async_cb
;
1001 ctx
->esp
= (ctx
->esp
- 16) & ~15;
1002 ctx
->eip
= (mgreg_t
)signal_exception_trampoline
;
1006 mono_arch_handle_exception (void *sigctx
, gpointer obj
)
1008 #if defined(MONO_ARCH_USE_SIGACTION)
1010 ucontext_t
*ctx
= (ucontext_t
*)sigctx
;
1013 * Handling the exception in the signal handler is problematic, since the original
1014 * signal is disabled, and we could run arbitrary code though the debugger. So
1015 * resume into the normal stack and do most work there if possible.
1017 MonoJitTlsData
*jit_tls
= mono_tls_get_jit_tls ();
1019 /* Pass the ctx parameter in TLS */
1020 mono_sigctx_to_monoctx (ctx
, &jit_tls
->ex_ctx
);
1022 mctx
= jit_tls
->ex_ctx
;
1023 mono_setup_async_callback (&mctx
, handle_signal_exception
, obj
);
1024 mono_monoctx_to_sigctx (&mctx
, sigctx
);
1027 #elif defined (TARGET_WIN32)
1029 MonoJitTlsData
*jit_tls
= mono_tls_get_jit_tls ();
1030 struct sigcontext
*ctx
= (struct sigcontext
*)sigctx
;
1032 mono_sigctx_to_monoctx (sigctx
, &jit_tls
->ex_ctx
);
1034 mctx
= jit_tls
->ex_ctx
;
1035 mono_setup_async_callback (&mctx
, handle_signal_exception
, obj
);
1036 mono_monoctx_to_sigctx (&mctx
, sigctx
);
1042 mono_sigctx_to_monoctx (sigctx
, &mctx
);
1044 mono_handle_exception (&mctx
, obj
);
1046 mono_monoctx_to_sigctx (&mctx
, sigctx
);
1053 restore_soft_guard_pages (void)
1055 MonoJitTlsData
*jit_tls
= mono_tls_get_jit_tls ();
1056 if (jit_tls
->stack_ovf_guard_base
)
1057 mono_mprotect (jit_tls
->stack_ovf_guard_base
, jit_tls
->stack_ovf_guard_size
, MONO_MMAP_NONE
);
1061 * this function modifies mctx so that when it is restored, it
1062 * won't execcute starting at mctx.eip, but in a function that
1063 * will restore the protection on the soft-guard pages and return back to
1064 * continue at mctx.eip.
1067 prepare_for_guard_pages (MonoContext
*mctx
)
1070 sp
= (gpointer
)(mctx
->esp
);
1072 /* the resturn addr */
1073 sp
[0] = (gpointer
)(mctx
->eip
);
1074 mctx
->eip
= (unsigned long)restore_soft_guard_pages
;
1075 mctx
->esp
= (unsigned long)sp
;
1079 altstack_handle_and_restore (MonoContext
*ctx
, gpointer obj
, gboolean stack_ovf
)
1085 mono_handle_exception (&mctx
, obj
);
1087 prepare_for_guard_pages (&mctx
);
1088 mono_restore_context (&mctx
);
1092 mono_arch_handle_altstack_exception (void *sigctx
, MONO_SIG_HANDLER_INFO_TYPE
*siginfo
, gpointer fault_addr
, gboolean stack_ovf
)
1094 #ifdef MONO_ARCH_USE_SIGACTION
1095 MonoException
*exc
= NULL
;
1096 ucontext_t
*ctx
= (ucontext_t
*)sigctx
;
1097 MonoJitInfo
*ji
= mini_jit_info_table_find (mono_domain_get (), (gpointer
)UCONTEXT_REG_EIP (ctx
), NULL
);
1101 /* if we didn't find a managed method for the ip address and it matches the fault
1102 * address, we assume we followed a broken pointer during an indirect call, so
1103 * we try the lookup again with the return address pushed on the stack
1105 if (!ji
&& fault_addr
== (gpointer
)UCONTEXT_REG_EIP (ctx
)) {
1106 glong
*sp
= (gpointer
)UCONTEXT_REG_ESP (ctx
);
1107 ji
= mini_jit_info_table_find (mono_domain_get (), (gpointer
)sp
[0], NULL
);
1109 UCONTEXT_REG_EIP (ctx
) = sp
[0];
1112 exc
= mono_domain_get ()->stack_overflow_ex
;
1114 mono_handle_native_crash ("SIGSEGV", sigctx
, siginfo
);
1115 /* setup a call frame on the real stack so that control is returned there
1116 * and exception handling can continue.
1117 * If this was a stack overflow the caller already ensured the stack pages
1118 * needed have been unprotected.
1119 * The frame looks like:
1126 // FIXME: test_only is no more.
1127 frame_size
= sizeof (MonoContext
) + sizeof (gpointer
) * 4;
1130 sp
= (gpointer
)(UCONTEXT_REG_ESP (ctx
) & ~15);
1131 sp
= (gpointer
)((char*)sp
- frame_size
);
1132 /* the incoming arguments are aligned to 16 bytes boundaries, so the return address IP
1135 sp
[-1] = (gpointer
)UCONTEXT_REG_EIP (ctx
);
1138 sp
[2] = (gpointer
)stack_ovf
;
1139 mono_sigctx_to_monoctx (sigctx
, (MonoContext
*)(sp
+ 4));
1140 /* at the return form the signal handler execution starts in altstack_handle_and_restore() */
1141 UCONTEXT_REG_EIP (ctx
) = (unsigned long)altstack_handle_and_restore
;
1142 UCONTEXT_REG_ESP (ctx
) = (unsigned long)(sp
- 1);
1146 #if MONO_SUPPORT_TASKLETS
1147 MonoContinuationRestore
1148 mono_tasklets_arch_restore (void)
1150 static guint8
* saved
= NULL
;
1151 guint8
*code
, *start
;
1154 return (MonoContinuationRestore
)saved
;
1155 code
= start
= mono_global_codeman_reserve (48);
1156 /* the signature is: restore (MonoContinuation *cont, int state, MonoLMF **lmf_addr) */
1157 /* put cont in edx */
1158 x86_mov_reg_membase (code
, X86_EDX
, X86_ESP
, 4, 4);
1159 /* state in eax, so it's setup as the return value */
1160 x86_mov_reg_membase (code
, X86_EAX
, X86_ESP
, 8, 4);
1161 /* lmf_addr in ebx */
1162 x86_mov_reg_membase(code
, X86_EBX
, X86_ESP
, 0x0C, 4);
1164 /* setup the copy of the stack */
1165 x86_mov_reg_membase (code
, X86_ECX
, X86_EDX
, MONO_STRUCT_OFFSET (MonoContinuation
, stack_used_size
), 4);
1166 x86_shift_reg_imm (code
, X86_SHR
, X86_ECX
, 2);
1168 x86_mov_reg_membase (code
, X86_ESI
, X86_EDX
, MONO_STRUCT_OFFSET (MonoContinuation
, saved_stack
), 4);
1169 x86_mov_reg_membase (code
, X86_EDI
, X86_EDX
, MONO_STRUCT_OFFSET (MonoContinuation
, return_sp
), 4);
1170 x86_prefix (code
, X86_REP_PREFIX
);
1173 /* now restore the registers from the LMF */
1174 x86_mov_reg_membase (code
, X86_ECX
, X86_EDX
, MONO_STRUCT_OFFSET (MonoContinuation
, lmf
), 4);
1175 x86_mov_reg_membase (code
, X86_EBP
, X86_ECX
, MONO_STRUCT_OFFSET (MonoLMF
, ebp
), 4);
1176 x86_mov_reg_membase (code
, X86_ESP
, X86_ECX
, MONO_STRUCT_OFFSET (MonoLMF
, esp
), 4);
1178 /* restore the lmf chain */
1179 /*x86_mov_reg_membase (code, X86_ECX, X86_ESP, 12, 4);
1180 x86_mov_membase_reg (code, X86_ECX, 0, X86_EDX, 4);*/
1182 x86_jump_membase (code
, X86_EDX
, MONO_STRUCT_OFFSET (MonoContinuation
, return_ip
));
1183 g_assert ((code
- start
) <= 48);
1185 return (MonoContinuationRestore
)saved
;
1190 * mono_arch_setup_resume_sighandler_ctx:
1192 * Setup CTX so execution continues at FUNC.
1195 mono_arch_setup_resume_sighandler_ctx (MonoContext
*ctx
, gpointer func
)
1197 int align
= (((gint32
)MONO_CONTEXT_GET_SP (ctx
)) % MONO_ARCH_FRAME_ALIGNMENT
+ 4);
1200 MONO_CONTEXT_SET_SP (ctx
, (gsize
)MONO_CONTEXT_GET_SP (ctx
) - align
);
1202 MONO_CONTEXT_SET_IP (ctx
, func
);