2 * tramp-x86.c: JIT trampoline code for x86
5 * Dietmar Maurer (dietmar@ximian.com)
7 * (C) 2001 Ximian, Inc.
13 #include <mono/metadata/appdomain.h>
14 #include <mono/metadata/metadata-internals.h>
15 #include <mono/metadata/marshal.h>
16 #include <mono/metadata/tabledefs.h>
17 #include <mono/metadata/mono-debug.h>
18 #include <mono/metadata/mono-debug-debugger.h>
19 #include <mono/metadata/monitor.h>
20 #include <mono/arch/x86/x86-codegen.h>
22 #include <mono/utils/memcheck.h>
27 static guint8* nullified_class_init_trampoline;
30 * mono_arch_get_unbox_trampoline:
31 * @gsctx: the generic sharing context
33 * @addr: pointer to native code for @m
35 * when value type methods are called through the vtable we need to unbox the
36 * this argument. This method returns a pointer to a trampoline which does
37 * unboxing before calling the method
40 mono_arch_get_unbox_trampoline (MonoGenericSharingContext *gsctx, MonoMethod *m, gpointer addr)
44 MonoDomain *domain = mono_domain_get ();
46 start = code = mono_domain_code_reserve (domain, 16);
48 x86_alu_membase_imm (code, X86_ADD, X86_ESP, this_pos, sizeof (MonoObject));
49 x86_jump_code (code, addr);
50 g_assert ((code - start) < 16);
56 mono_arch_get_static_rgctx_trampoline (MonoMethod *m, MonoMethodRuntimeGenericContext *mrgctx, gpointer addr)
61 MonoDomain *domain = mono_domain_get ();
65 start = code = mono_domain_code_reserve (domain, buf_len);
67 x86_mov_reg_imm (code, MONO_ARCH_RGCTX_REG, mrgctx);
68 x86_jump_code (code, addr);
69 g_assert ((code - start) <= buf_len);
71 mono_arch_flush_icache (start, code - start);
77 mono_arch_get_llvm_imt_trampoline (MonoDomain *domain, MonoMethod *m, int vt_offset)
85 start = code = mono_domain_code_reserve (domain, buf_len);
87 this_offset = mono_x86_get_this_arg_offset (NULL, mono_method_signature (m));
90 x86_mov_reg_imm (code, MONO_ARCH_IMT_REG, m);
92 x86_mov_reg_membase (code, X86_EAX, X86_ESP, this_offset + 4, 4);
93 /* Load vtable address */
94 x86_mov_reg_membase (code, X86_EAX, X86_EAX, 0, 4);
95 x86_jump_membase (code, X86_EAX, vt_offset);
97 g_assert ((code - start) < buf_len);
99 mono_arch_flush_icache (start, code - start);
105 mono_arch_patch_callsite (guint8 *method_start, guint8 *orig_code, guint8 *addr)
109 gboolean can_write = mono_breakpoint_clean_code (method_start, orig_code, 8, buf, sizeof (buf));
113 /* go to the start of the call instruction
115 * address_byte = (m << 6) | (o << 3) | reg
116 * call opcode: 0xff address_byte displacement
122 if ((code [1] == 0xe8)) {
124 InterlockedExchange ((gint32*)(orig_code + 2), (guint)addr - ((guint)orig_code + 1) - 5);
126 /* Tell valgrind to recompile the patched code */
127 VALGRIND_DISCARD_TRANSLATIONS (orig_code + 2, 4);
129 } else if (code [1] == 0xe9) {
130 /* A PLT entry: jmp <DISP> */
132 InterlockedExchange ((gint32*)(orig_code + 2), (guint)addr - ((guint)orig_code + 1) - 5);
134 printf ("Invalid trampoline sequence: %x %x %x %x %x %x %x\n", code [0], code [1], code [2], code [3],
135 code [4], code [5], code [6]);
136 g_assert_not_reached ();
141 mono_arch_patch_plt_entry (guint8 *code, gpointer *got, mgreg_t *regs, guint8 *addr)
145 /* Patch the jump table entry used by the plt entry */
147 /* A PLT entry: jmp *<DISP>(%ebx) */
148 g_assert (code [0] == 0xff);
149 g_assert (code [1] == 0xa3);
151 offset = *(guint32*)(code + 2);
154 got = (gpointer*)(gsize) regs [MONO_ARCH_GOT_REG];
155 *(guint8**)((guint8*)got + offset) = addr;
159 get_vcall_slot (guint8 *code, mgreg_t *regs, int *displacement)
165 mono_breakpoint_clean_code (NULL, code, 8, buf, sizeof (buf));
172 if ((code [0] == 0xff) && ((code [1] & 0x18) == 0x10) && ((code [1] >> 6) == 2)) {
173 reg = code [1] & 0x07;
174 disp = *((gint32*)(code + 2));
176 g_assert_not_reached ();
180 *displacement = disp;
181 return (gpointer)regs [reg];
185 get_vcall_slot_addr (guint8* code, mgreg_t *regs)
189 vt = get_vcall_slot (code, regs, &displacement);
192 return (gpointer*)((char*)vt + displacement);
196 mono_arch_nullify_class_init_trampoline (guint8 *code, mgreg_t *regs)
199 gboolean can_write = mono_breakpoint_clean_code (NULL, code, 6, buf, sizeof (buf));
205 if (code [0] == 0xe8) {
206 if (!mono_running_on_valgrind ()) {
209 * Thread safe code patching using the algorithm from the paper
210 * 'Practicing JUDO: Java Under Dynamic Optimizations'
213 * First atomically change the the first 2 bytes of the call to a
217 InterlockedExchange ((gint32*)code, ops);
219 /* Then change the other bytes to a nop */
224 /* Then atomically change the first 4 bytes to a nop as well */
226 InterlockedExchange ((gint32*)code, ops);
227 /* FIXME: the calltree skin trips on the self modifying code above */
229 /* Tell valgrind to recompile the patched code */
230 //VALGRIND_DISCARD_TRANSLATIONS (code, 8);
232 } else if (code [0] == 0x90 || code [0] == 0xeb) {
233 /* Already changed by another thread */
235 } else if ((code [-1] == 0xff) && (x86_modrm_reg (code [0]) == 0x2)) {
236 /* call *<OFFSET>(<REG>) -> Call made from AOT code */
237 gpointer *vtable_slot;
239 vtable_slot = get_vcall_slot_addr (code + 5, regs);
240 g_assert (vtable_slot);
242 *vtable_slot = nullified_class_init_trampoline;
244 printf ("Invalid trampoline sequence: %x %x %x %x %x %x %x\n", code [0], code [1], code [2], code [3],
245 code [4], code [5], code [6]);
246 g_assert_not_reached ();
251 mono_arch_nullify_plt_entry (guint8 *code, mgreg_t *regs)
253 if (mono_aot_only && !nullified_class_init_trampoline)
254 nullified_class_init_trampoline = mono_aot_get_trampoline ("nullified_class_init_trampoline");
256 mono_arch_patch_plt_entry (code, NULL, regs, nullified_class_init_trampoline);
260 mono_arch_create_generic_trampoline (MonoTrampolineType tramp_type, MonoTrampInfo **info, gboolean aot)
262 guint8 *buf, *code, *tramp;
263 int pushed_args, pushed_args_caller_saved;
264 GSList *unwind_ops = NULL;
265 MonoJumpInfo *ji = NULL;
267 unwind_ops = mono_arch_get_cie_program ();
269 code = buf = mono_global_codeman_reserve (256);
271 /* Note that there is a single argument to the trampoline
272 * and it is stored at: esp + pushed_args * sizeof (gpointer)
273 * the ret address is at: esp + (pushed_args + 1) * sizeof (gpointer)
276 /* Put all registers into an array on the stack
277 * If this code is changed, make sure to update the offset value in
278 * mono_arch_get_this_arg_from_call () in mini-x86.c.
280 x86_push_reg (code, X86_EDI);
281 x86_push_reg (code, X86_ESI);
282 x86_push_reg (code, X86_EBP);
283 x86_push_reg (code, X86_ESP);
284 x86_push_reg (code, X86_EBX);
285 x86_push_reg (code, X86_EDX);
286 x86_push_reg (code, X86_ECX);
287 x86_push_reg (code, X86_EAX);
289 pushed_args_caller_saved = pushed_args = 8;
291 /* Align stack on apple */
292 x86_alu_reg_imm (code, X86_SUB, X86_ESP, 4);
298 /* save the IP (caller ip) */
299 if (tramp_type == MONO_TRAMPOLINE_JUMP)
300 x86_push_imm (code, 0);
302 x86_push_membase (code, X86_ESP, (pushed_args + 1) * sizeof (gpointer));
306 x86_push_reg (code, X86_EBP);
307 x86_push_reg (code, X86_ESI);
308 x86_push_reg (code, X86_EDI);
309 x86_push_reg (code, X86_EBX);
314 x86_push_reg (code, X86_ESP);
315 /* Adjust ESP so it points to the previous frame */
316 x86_alu_membase_imm (code, X86_ADD, X86_ESP, 0, (pushed_args + 2) * 4);
320 /* save method info */
321 if ((tramp_type == MONO_TRAMPOLINE_JIT) || (tramp_type == MONO_TRAMPOLINE_JUMP))
322 x86_push_membase (code, X86_ESP, pushed_args * sizeof (gpointer));
324 x86_push_imm (code, 0);
328 /* On apple, the stack is correctly aligned to 16 bytes because pushed_args is
329 * 16 and there is the extra trampoline arg + the return ip pushed by call
330 * FIXME: Note that if an exception happens while some args are pushed
331 * on the stack, the stack will be misaligned.
333 g_assert (pushed_args == 16);
335 /* get the address of lmf for the current thread */
337 code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_get_lmf_addr");
338 x86_call_reg (code, X86_EAX);
340 x86_call_code (code, mono_get_lmf_addr);
343 x86_push_reg (code, X86_EAX);
344 /* push *lfm (previous_lmf) */
345 x86_push_membase (code, X86_EAX, 0);
346 /* Signal to mono_arch_find_jit_info () that this is a trampoline frame */
347 x86_alu_membase_imm (code, X86_ADD, X86_ESP, 0, 1);
349 x86_mov_membase_reg (code, X86_EAX, 0, X86_ESP, 4);
354 /* starting the call sequence */
356 /* FIXME: Push the trampoline address */
357 x86_push_imm (code, 0);
361 /* push the method info */
362 x86_push_membase (code, X86_ESP, pushed_args * sizeof (gpointer));
366 /* push the return address onto the stack */
367 if (tramp_type == MONO_TRAMPOLINE_JUMP)
368 x86_push_imm (code, 0);
370 x86_push_membase (code, X86_ESP, (pushed_args + 1) * sizeof (gpointer));
372 /* push the address of the register array */
373 x86_lea_membase (code, X86_EAX, X86_ESP, (pushed_args - 8) * sizeof (gpointer));
374 x86_push_reg (code, X86_EAX);
379 /* check the stack is aligned after the ret ip is pushed */
380 /*x86_mov_reg_reg (buf, X86_EDX, X86_ESP, 4);
381 x86_alu_reg_imm (buf, X86_AND, X86_EDX, 15);
382 x86_alu_reg_imm (buf, X86_CMP, X86_EDX, 0);
383 x86_branch_disp (buf, X86_CC_Z, 3, FALSE);
384 x86_breakpoint (buf);*/
387 mono_add_unwind_op_def_cfa (unwind_ops, code, buf, X86_ESP, ((pushed_args + 2) * 4));
390 char *icall_name = g_strdup_printf ("trampoline_func_%d", tramp_type);
391 code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, icall_name);
392 x86_call_reg (code, X86_EAX);
394 tramp = (guint8*)mono_get_trampoline_func (tramp_type);
395 x86_call_code (code, tramp);
398 x86_alu_reg_imm (code, X86_ADD, X86_ESP, 4*4);
402 /* Check for thread interruption */
403 /* This is not perf critical code so no need to check the interrupt flag */
404 /* Align the stack on osx */
405 x86_alu_reg_imm (code, X86_SUB, X86_ESP, 3 * 4);
406 x86_push_reg (code, X86_EAX);
408 code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "mono_thread_force_interruption_checkpoint");
409 x86_call_reg (code, X86_EAX);
411 x86_call_code (code, (guint8*)mono_thread_force_interruption_checkpoint);
413 x86_pop_reg (code, X86_EAX);
414 x86_alu_reg_imm (code, X86_ADD, X86_ESP, 3 * 4);
418 /* ebx = previous_lmf */
419 x86_pop_reg (code, X86_EBX);
421 x86_alu_reg_imm (code, X86_SUB, X86_EBX, 1);
424 x86_pop_reg (code, X86_EDI);
427 /* *(lmf) = previous_lmf */
428 x86_mov_membase_reg (code, X86_EDI, 0, X86_EBX, 4);
430 /* discard method info */
431 x86_pop_reg (code, X86_ESI);
435 x86_pop_reg (code, X86_ESI);
438 /* restore caller saved regs */
439 x86_pop_reg (code, X86_EBX);
440 x86_pop_reg (code, X86_EDI);
441 x86_pop_reg (code, X86_ESI);
442 x86_pop_reg (code, X86_EBP);
446 /* discard save IP */
447 x86_alu_reg_imm (code, X86_ADD, X86_ESP, 4);
450 /* restore LMF end */
452 if (!MONO_TRAMPOLINE_TYPE_MUST_RETURN (tramp_type)) {
454 * Overwrite the method ptr with the address we need to jump to,
457 x86_mov_membase_reg (code, X86_ESP, pushed_args * sizeof (gpointer), X86_EAX, 4);
460 /* Restore caller saved registers */
461 x86_mov_reg_membase (code, X86_ECX, X86_ESP, (pushed_args - pushed_args_caller_saved + X86_ECX) * 4, 4);
462 x86_mov_reg_membase (code, X86_EDX, X86_ESP, (pushed_args - pushed_args_caller_saved + X86_EDX) * 4, 4);
463 if ((tramp_type == MONO_TRAMPOLINE_RESTORE_STACK_PROT) || (tramp_type == MONO_TRAMPOLINE_AOT_PLT))
464 x86_mov_reg_membase (code, X86_EAX, X86_ESP, (pushed_args - pushed_args_caller_saved + X86_EAX) * 4, 4);
466 if (!MONO_TRAMPOLINE_TYPE_MUST_RETURN (tramp_type)) {
467 /* Pop saved reg array + stack align */
468 x86_alu_reg_imm (code, X86_ADD, X86_ESP, 9 * 4);
470 g_assert (pushed_args == 0);
472 /* Pop saved reg array + stack align + method ptr */
473 x86_alu_reg_imm (code, X86_ADD, X86_ESP, 10 * 4);
476 /* We've popped one more stack item than we've pushed (the
477 method ptr argument), so we must end up at -1. */
478 g_assert (pushed_args == -1);
483 g_assert ((code - buf) <= 256);
486 *info = mono_tramp_info_create (mono_get_generic_trampoline_name (tramp_type), buf, code - buf, ji, unwind_ops);
488 if (tramp_type == MONO_TRAMPOLINE_CLASS_INIT) {
489 /* Initialize the nullified class init trampoline used in the AOT case */
490 nullified_class_init_trampoline = mono_arch_get_nullified_class_init_trampoline (NULL);
497 mono_arch_get_nullified_class_init_trampoline (MonoTrampInfo **info)
501 code = buf = mono_global_codeman_reserve (16);
504 mono_arch_flush_icache (buf, code - buf);
507 *info = mono_tramp_info_create (g_strdup_printf ("nullified_class_init_trampoline"), buf, code - buf, NULL, NULL);
512 #define TRAMPOLINE_SIZE 10
515 mono_arch_create_specific_trampoline (gpointer arg1, MonoTrampolineType tramp_type, MonoDomain *domain, guint32 *code_len)
517 guint8 *code, *buf, *tramp;
519 tramp = mono_get_trampoline_code (tramp_type);
521 code = buf = mono_domain_code_reserve_align (domain, TRAMPOLINE_SIZE, 4);
523 x86_push_imm (buf, arg1);
524 x86_jump_code (buf, tramp);
525 g_assert ((buf - code) <= TRAMPOLINE_SIZE);
527 mono_arch_flush_icache (code, buf - code);
530 *code_len = buf - code;
536 mono_arch_create_rgctx_lazy_fetch_trampoline (guint32 slot, MonoTrampInfo **info, gboolean aot)
540 guint8 **rgctx_null_jumps;
545 MonoJumpInfo *ji = NULL;
546 GSList *unwind_ops = NULL;
548 unwind_ops = mono_arch_get_cie_program ();
550 mrgctx = MONO_RGCTX_SLOT_IS_MRGCTX (slot);
551 index = MONO_RGCTX_SLOT_INDEX (slot);
553 index += MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT / sizeof (gpointer);
554 for (depth = 0; ; ++depth) {
555 int size = mono_class_rgctx_get_array_size (depth, mrgctx);
557 if (index < size - 1)
562 tramp_size = (aot ? 64 : 36) + 6 * depth;
564 code = buf = mono_global_codeman_reserve (tramp_size);
566 rgctx_null_jumps = g_malloc (sizeof (guint8*) * (depth + 2));
568 /* load vtable/mrgctx ptr */
569 x86_mov_reg_membase (code, X86_EAX, X86_ESP, 4, 4);
571 /* load rgctx ptr from vtable */
572 x86_mov_reg_membase (code, X86_EAX, X86_EAX, G_STRUCT_OFFSET (MonoVTable, runtime_generic_context), 4);
573 /* is the rgctx ptr null? */
574 x86_test_reg_reg (code, X86_EAX, X86_EAX);
575 /* if yes, jump to actual trampoline */
576 rgctx_null_jumps [0] = code;
577 x86_branch8 (code, X86_CC_Z, -1, 1);
580 for (i = 0; i < depth; ++i) {
581 /* load ptr to next array */
582 if (mrgctx && i == 0)
583 x86_mov_reg_membase (code, X86_EAX, X86_EAX, MONO_SIZEOF_METHOD_RUNTIME_GENERIC_CONTEXT, 4);
585 x86_mov_reg_membase (code, X86_EAX, X86_EAX, 0, 4);
586 /* is the ptr null? */
587 x86_test_reg_reg (code, X86_EAX, X86_EAX);
588 /* if yes, jump to actual trampoline */
589 rgctx_null_jumps [i + 1] = code;
590 x86_branch8 (code, X86_CC_Z, -1, 1);
594 x86_mov_reg_membase (code, X86_EAX, X86_EAX, sizeof (gpointer) * (index + 1), 4);
595 /* is the slot null? */
596 x86_test_reg_reg (code, X86_EAX, X86_EAX);
597 /* if yes, jump to actual trampoline */
598 rgctx_null_jumps [depth + 1] = code;
599 x86_branch8 (code, X86_CC_Z, -1, 1);
600 /* otherwise return */
603 for (i = mrgctx ? 1 : 0; i <= depth + 1; ++i)
604 x86_patch (rgctx_null_jumps [i], code);
606 g_free (rgctx_null_jumps);
608 x86_mov_reg_membase (code, MONO_ARCH_VTABLE_REG, X86_ESP, 4, 4);
611 code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, g_strdup_printf ("specific_trampoline_lazy_fetch_%u", slot));
612 x86_jump_reg (code, X86_EAX);
614 tramp = mono_arch_create_specific_trampoline (GUINT_TO_POINTER (slot), MONO_TRAMPOLINE_RGCTX_LAZY_FETCH, mono_get_root_domain (), NULL);
616 /* jump to the actual trampoline */
617 x86_jump_code (code, tramp);
620 mono_arch_flush_icache (buf, code - buf);
622 g_assert (code - buf <= tramp_size);
625 *info = mono_tramp_info_create (mono_get_rgctx_fetch_trampoline_name (slot), buf, code - buf, ji, unwind_ops);
631 mono_arch_create_generic_class_init_trampoline (MonoTrampInfo **info, gboolean aot)
635 static int byte_offset = -1;
636 static guint8 bitmask;
639 GSList *unwind_ops = NULL;
640 MonoJumpInfo *ji = NULL;
644 code = buf = mono_global_codeman_reserve (tramp_size);
646 unwind_ops = mono_arch_get_cie_program ();
649 mono_marshal_find_bitfield_offset (MonoVTable, initialized, &byte_offset, &bitmask);
651 x86_test_membase_imm (code, MONO_ARCH_VTABLE_REG, byte_offset, bitmask);
653 x86_branch8 (code, X86_CC_Z, -1, 1);
657 x86_patch (jump, code);
659 /* Push the vtable so the stack is the same as in a specific trampoline */
660 x86_push_reg (code, MONO_ARCH_VTABLE_REG);
663 code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "generic_trampoline_generic_class_init");
664 x86_jump_reg (code, X86_EAX);
666 tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_GENERIC_CLASS_INIT);
668 /* jump to the actual trampoline */
669 x86_jump_code (code, tramp);
672 mono_arch_flush_icache (code, code - buf);
674 g_assert (code - buf <= tramp_size);
677 *info = mono_tramp_info_create (g_strdup_printf ("generic_class_init_trampoline"), buf, code - buf, ji, unwind_ops);
682 #ifdef MONO_ARCH_MONITOR_OBJECT_REG
684 * The code produced by this trampoline is equivalent to this:
687 * if (obj->synchronisation) {
688 * if (obj->synchronisation->owner == 0) {
689 * if (cmpxch (&obj->synchronisation->owner, TID, 0) == 0)
692 * if (obj->synchronisation->owner == TID) {
693 * ++obj->synchronisation->nest;
698 * return full_monitor_enter ();
702 mono_arch_create_monitor_enter_trampoline (MonoTrampInfo **info, gboolean aot)
704 guint8 *tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_MONITOR_ENTER);
706 guint8 *jump_obj_null, *jump_sync_null, *jump_other_owner, *jump_cmpxchg_failed, *jump_tid;
708 int owner_offset, nest_offset, dummy;
709 MonoJumpInfo *ji = NULL;
710 GSList *unwind_ops = NULL;
712 g_assert (MONO_ARCH_MONITOR_OBJECT_REG == X86_EAX);
714 mono_monitor_threads_sync_members_offset (&owner_offset, &nest_offset, &dummy);
715 g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (owner_offset) == sizeof (gpointer));
716 g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (nest_offset) == sizeof (guint32));
717 owner_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (owner_offset);
718 nest_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (nest_offset);
722 code = buf = mono_global_codeman_reserve (tramp_size);
724 if (mono_thread_get_tls_offset () != -1) {
725 /* MonoObject* obj is in EAX */
727 x86_test_reg_reg (code, X86_EAX, X86_EAX);
728 /* if yes, jump to actual trampoline */
729 jump_obj_null = code;
730 x86_branch8 (code, X86_CC_Z, -1, 1);
732 /* load obj->synchronization to ECX */
733 x86_mov_reg_membase (code, X86_ECX, X86_EAX, G_STRUCT_OFFSET (MonoObject, synchronisation), 4);
734 /* is synchronization null? */
735 x86_test_reg_reg (code, X86_ECX, X86_ECX);
736 /* if yes, jump to actual trampoline */
737 jump_sync_null = code;
738 x86_branch8 (code, X86_CC_Z, -1, 1);
740 /* load MonoInternalThread* into EDX */
741 code = mono_x86_emit_tls_get (code, X86_EDX, mono_thread_get_tls_offset ());
742 /* load TID into EDX */
743 x86_mov_reg_membase (code, X86_EDX, X86_EDX, G_STRUCT_OFFSET (MonoInternalThread, tid), 4);
745 /* is synchronization->owner null? */
746 x86_alu_membase_imm (code, X86_CMP, X86_ECX, owner_offset, 0);
747 /* if not, jump to next case */
749 x86_branch8 (code, X86_CC_NZ, -1, 1);
751 /* if yes, try a compare-exchange with the TID */
752 /* free up register EAX, needed for the zero */
753 x86_push_reg (code, X86_EAX);
755 x86_alu_reg_reg (code, X86_XOR, X86_EAX, X86_EAX);
756 /* compare and exchange */
757 x86_prefix (code, X86_LOCK_PREFIX);
758 x86_cmpxchg_membase_reg (code, X86_ECX, owner_offset, X86_EDX);
759 /* if not successful, jump to actual trampoline */
760 jump_cmpxchg_failed = code;
761 x86_branch8 (code, X86_CC_NZ, -1, 1);
762 /* if successful, pop and return */
763 x86_pop_reg (code, X86_EAX);
766 /* next case: synchronization->owner is not null */
767 x86_patch (jump_tid, code);
768 /* is synchronization->owner == TID? */
769 x86_alu_membase_reg (code, X86_CMP, X86_ECX, owner_offset, X86_EDX);
770 /* if not, jump to actual trampoline */
771 jump_other_owner = code;
772 x86_branch8 (code, X86_CC_NZ, -1, 1);
773 /* if yes, increment nest */
774 x86_inc_membase (code, X86_ECX, nest_offset);
779 x86_patch (jump_obj_null, code);
780 x86_patch (jump_sync_null, code);
781 x86_patch (jump_other_owner, code);
782 x86_push_reg (code, X86_EAX);
783 /* jump to the actual trampoline */
784 x86_patch (jump_cmpxchg_failed, code);
786 /* We are calling the generic trampoline directly, the argument is pushed
787 * on the stack just like a specific trampoline.
789 code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "generic_trampoline_monitor_enter");
790 x86_jump_reg (code, X86_EAX);
792 x86_jump_code (code, tramp);
795 /* push obj and jump to the actual trampoline */
796 x86_push_reg (code, X86_EAX);
798 code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "generic_trampoline_monitor_enter");
799 x86_jump_reg (code, X86_EAX);
801 x86_jump_code (code, tramp);
805 mono_arch_flush_icache (buf, code - buf);
806 g_assert (code - buf <= tramp_size);
809 *info = mono_tramp_info_create (g_strdup_printf ("monitor_enter_trampoline"), buf, code - buf, ji, unwind_ops);
815 mono_arch_create_monitor_exit_trampoline (MonoTrampInfo **info, gboolean aot)
817 guint8 *tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_MONITOR_EXIT);
819 guint8 *jump_obj_null, *jump_have_waiters, *jump_sync_null, *jump_not_owned;
822 int owner_offset, nest_offset, entry_count_offset;
823 MonoJumpInfo *ji = NULL;
824 GSList *unwind_ops = NULL;
826 g_assert (MONO_ARCH_MONITOR_OBJECT_REG == X86_EAX);
828 mono_monitor_threads_sync_members_offset (&owner_offset, &nest_offset, &entry_count_offset);
829 g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (owner_offset) == sizeof (gpointer));
830 g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (nest_offset) == sizeof (guint32));
831 g_assert (MONO_THREADS_SYNC_MEMBER_SIZE (entry_count_offset) == sizeof (gint32));
832 owner_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (owner_offset);
833 nest_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (nest_offset);
834 entry_count_offset = MONO_THREADS_SYNC_MEMBER_OFFSET (entry_count_offset);
838 code = buf = mono_global_codeman_reserve (tramp_size);
840 if (mono_thread_get_tls_offset () != -1) {
841 /* MonoObject* obj is in EAX */
843 x86_test_reg_reg (code, X86_EAX, X86_EAX);
844 /* if yes, jump to actual trampoline */
845 jump_obj_null = code;
846 x86_branch8 (code, X86_CC_Z, -1, 1);
848 /* load obj->synchronization to ECX */
849 x86_mov_reg_membase (code, X86_ECX, X86_EAX, G_STRUCT_OFFSET (MonoObject, synchronisation), 4);
850 /* is synchronization null? */
851 x86_test_reg_reg (code, X86_ECX, X86_ECX);
852 /* if yes, jump to actual trampoline */
853 jump_sync_null = code;
854 x86_branch8 (code, X86_CC_Z, -1, 1);
856 /* next case: synchronization is not null */
857 /* load MonoInternalThread* into EDX */
858 code = mono_x86_emit_tls_get (code, X86_EDX, mono_thread_get_tls_offset ());
859 /* load TID into EDX */
860 x86_mov_reg_membase (code, X86_EDX, X86_EDX, G_STRUCT_OFFSET (MonoInternalThread, tid), 4);
861 /* is synchronization->owner == TID */
862 x86_alu_membase_reg (code, X86_CMP, X86_ECX, owner_offset, X86_EDX);
863 /* if no, jump to actual trampoline */
864 jump_not_owned = code;
865 x86_branch8 (code, X86_CC_NZ, -1, 1);
867 /* next case: synchronization->owner == TID */
868 /* is synchronization->nest == 1 */
869 x86_alu_membase_imm (code, X86_CMP, X86_ECX, nest_offset, 1);
870 /* if not, jump to next case */
872 x86_branch8 (code, X86_CC_NZ, -1, 1);
873 /* if yes, is synchronization->entry_count zero? */
874 x86_alu_membase_imm (code, X86_CMP, X86_ECX, entry_count_offset, 0);
875 /* if not, jump to actual trampoline */
876 jump_have_waiters = code;
877 x86_branch8 (code, X86_CC_NZ, -1 , 1);
878 /* if yes, set synchronization->owner to null and return */
879 x86_mov_membase_imm (code, X86_ECX, owner_offset, 0, 4);
882 /* next case: synchronization->nest is not 1 */
883 x86_patch (jump_next, code);
884 /* decrease synchronization->nest and return */
885 x86_dec_membase (code, X86_ECX, nest_offset);
888 /* push obj and jump to the actual trampoline */
889 x86_patch (jump_obj_null, code);
890 x86_patch (jump_have_waiters, code);
891 x86_patch (jump_not_owned, code);
892 x86_patch (jump_sync_null, code);
895 /* push obj and jump to the actual trampoline */
896 x86_push_reg (code, X86_EAX);
898 code = mono_arch_emit_load_aotconst (buf, code, &ji, MONO_PATCH_INFO_JIT_ICALL_ADDR, "generic_trampoline_monitor_exit");
899 x86_jump_reg (code, X86_EAX);
901 x86_jump_code (code, tramp);
904 mono_arch_flush_icache (buf, code - buf);
905 g_assert (code - buf <= tramp_size);
908 *info = mono_tramp_info_create (g_strdup_printf ("monitor_exit_trampoline"), buf, code - buf, ji, unwind_ops);
916 mono_arch_create_monitor_enter_trampoline (MonoTrampInfo **info, gboolean aot)
918 g_assert_not_reached ();
923 mono_arch_create_monitor_exit_trampoline (MonoTrampInfo **info, gboolean aot)
925 g_assert_not_reached ();
932 mono_arch_invalidate_method (MonoJitInfo *ji, void *func, gpointer func_arg)
934 /* FIXME: This is not thread safe */
935 guint8 *code = ji->code_start;
937 x86_push_imm (code, func_arg);
938 x86_call_code (code, (guint8*)func);
942 handler_block_trampoline_helper (gpointer *ptr)
944 MonoJitTlsData *jit_tls = TlsGetValue (mono_jit_tls_id);
945 *ptr = jit_tls->handler_block_return_address;
949 mono_arch_create_handler_block_trampoline (void)
951 guint8 *tramp = mono_get_trampoline_code (MONO_TRAMPOLINE_HANDLER_BLOCK_GUARD);
954 code = buf = mono_global_codeman_reserve (tramp_size);
957 This trampoline restore the call chain of the handler block then jumps into the code that deals with it.
960 if (mono_get_jit_tls_offset () != -1) {
961 code = mono_x86_emit_tls_get (code, X86_EAX, mono_get_jit_tls_offset ());
962 x86_mov_reg_membase (code, X86_EAX, X86_EAX, G_STRUCT_OFFSET (MonoJitTlsData, handler_block_return_address), 4);
964 x86_push_reg (code, X86_EAX);
965 x86_jump_code (code, tramp);
967 /*Slow path uses a c helper*/
968 x86_push_reg (code, X86_ESP);
969 x86_push_imm (code, tramp);
970 x86_jump_code (code, handler_block_trampoline_helper);
973 mono_arch_flush_icache (buf, code - buf);
974 g_assert (code - buf <= tramp_size);
980 mono_arch_get_call_target (guint8 *code)
982 if (code [-5] == 0xe8) {
983 guint32 disp = *(guint32*)(code - 4);
984 guint8 *target = code + disp;
993 mono_arch_get_plt_info_offset (guint8 *plt_entry, mgreg_t *regs, guint8 *code)
995 return *(guint32*)(plt_entry + 6);