/** * mono_gc_get_managed_allocator_by_type: * * Return a managed allocator method corresponding to allocator type ATYPE. */ MonoMethod* mono_gc_get_managed_allocator_by_type (int atype) { int offset = -1; MonoMethod *res; MONO_THREAD_VAR_OFFSET (GC_thread_tls, offset); mono_tls_key_set_offset (TLS_KEY_BOEHM_GC_THREAD, offset); res = alloc_method_cache [atype]; if (res) return res; res = create_allocator (atype, TLS_KEY_BOEHM_GC_THREAD); mono_mutex_lock (&mono_gc_lock); if (alloc_method_cache [atype]) { mono_free_method (res); res = alloc_method_cache [atype]; } else { mono_memory_barrier (); alloc_method_cache [atype] = res; } mono_mutex_unlock (&mono_gc_lock); return res; }
void sgen_init_allocator (void) { #if defined(HAVE_KW_THREAD) && !defined(SGEN_WITHOUT_MONO) int tlab_next_addr_offset = -1; int tlab_temp_end_offset = -1; MONO_THREAD_VAR_OFFSET (tlab_next_addr, tlab_next_addr_offset); MONO_THREAD_VAR_OFFSET (tlab_temp_end, tlab_temp_end_offset); mono_tls_key_set_offset (TLS_KEY_SGEN_TLAB_NEXT_ADDR, tlab_next_addr_offset); mono_tls_key_set_offset (TLS_KEY_SGEN_TLAB_TEMP_END, tlab_temp_end_offset); #endif #ifdef HEAVY_STATISTICS mono_counters_register ("# objects allocated", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_objects_alloced); mono_counters_register ("bytes allocated", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_bytes_alloced); mono_counters_register ("bytes allocated in LOS", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_bytes_alloced_los); #endif }
/** * mono_gc_get_managed_allocator_by_type: * * Return a managed allocator method corresponding to allocator type ATYPE. */ MonoMethod* mono_gc_get_managed_allocator_by_type (int atype) { int offset = -1; MonoMethod *res; MONO_THREAD_VAR_OFFSET (GC_thread_tls, offset); mono_tls_key_set_offset (TLS_KEY_BOEHM_GC_THREAD, offset); mono_loader_lock (); res = alloc_method_cache [atype]; if (!res) res = alloc_method_cache [atype] = create_allocator (atype, TLS_KEY_BOEHM_GC_THREAD); mono_loader_unlock (); return res; }
/* FIXME: Do this in the JIT, where specialized allocation sequences can be created * for each class. This is currently not easy to do, as it is hard to generate basic * blocks + branches, but it is easy with the linear IL codebase. * * For this to work we'd need to solve the TLAB race, first. Now we * require the allocator to be in a few known methods to make sure * that they are executed atomically via the restart mechanism. */ static MonoMethod* create_allocator (int atype) { int p_var, size_var; guint32 slowpath_branch, max_size_branch; MonoMethodBuilder *mb; MonoMethod *res; MonoMethodSignature *csig; static gboolean registered = FALSE; int tlab_next_addr_var, new_next_var; int num_params, i; const char *name = NULL; AllocatorWrapperInfo *info; #ifdef HAVE_KW_THREAD int tlab_next_addr_offset = -1; int tlab_temp_end_offset = -1; MONO_THREAD_VAR_OFFSET (tlab_next_addr, tlab_next_addr_offset); MONO_THREAD_VAR_OFFSET (tlab_temp_end, tlab_temp_end_offset); mono_tls_key_set_offset (TLS_KEY_SGEN_TLAB_NEXT_ADDR, tlab_next_addr_offset); mono_tls_key_set_offset (TLS_KEY_SGEN_TLAB_TEMP_END, tlab_temp_end_offset); g_assert (tlab_next_addr_offset != -1); g_assert (tlab_temp_end_offset != -1); #endif if (!registered) { mono_register_jit_icall (mono_gc_alloc_obj, "mono_gc_alloc_obj", mono_create_icall_signature ("object ptr int"), FALSE); mono_register_jit_icall (mono_gc_alloc_vector, "mono_gc_alloc_vector", mono_create_icall_signature ("object ptr int int"), FALSE); mono_register_jit_icall (mono_gc_alloc_string, "mono_gc_alloc_string", mono_create_icall_signature ("object ptr int int32"), FALSE); registered = TRUE; } if (atype == ATYPE_SMALL) { num_params = 1; name = "AllocSmall"; } else if (atype == ATYPE_NORMAL) { num_params = 1; name = "Alloc"; } else if (atype == ATYPE_VECTOR) { num_params = 2; name = "AllocVector"; } else if (atype == ATYPE_STRING) { num_params = 2; name = "AllocString"; } else { g_assert_not_reached (); } csig = mono_metadata_signature_alloc (mono_defaults.corlib, num_params); if (atype == ATYPE_STRING) { csig->ret = &mono_defaults.string_class->byval_arg; csig->params [0] = &mono_defaults.int_class->byval_arg; csig->params [1] = &mono_defaults.int32_class->byval_arg; } else { csig->ret = &mono_defaults.object_class->byval_arg; for (i = 0; i < num_params; ++i) csig->params [i] = &mono_defaults.int_class->byval_arg; } mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC); #ifndef DISABLE_JIT size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg); if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) { /* size = vtable->klass->instance_size; */ mono_mb_emit_ldarg (mb, 0); mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoVTable, klass)); mono_mb_emit_byte (mb, CEE_ADD); mono_mb_emit_byte (mb, CEE_LDIND_I); mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoClass, instance_size)); mono_mb_emit_byte (mb, CEE_ADD); /* FIXME: assert instance_size stays a 4 byte integer */ mono_mb_emit_byte (mb, CEE_LDIND_U4); mono_mb_emit_byte (mb, CEE_CONV_I); mono_mb_emit_stloc (mb, size_var); } else if (atype == ATYPE_VECTOR) { MonoExceptionClause *clause; int pos, pos_leave, pos_error; MonoClass *oom_exc_class; MonoMethod *ctor; /* * n > MONO_ARRAY_MAX_INDEX => OutOfMemoryException * n < 0 => OverflowException * * We can do an unsigned comparison to catch both cases, then in the error * case compare signed to distinguish between them. */ mono_mb_emit_ldarg (mb, 1); mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX); mono_mb_emit_byte (mb, CEE_CONV_U); pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S); mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX); mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN); mono_mb_emit_ldarg (mb, 1); mono_mb_emit_icon (mb, 0); pos_error = mono_mb_emit_short_branch (mb, CEE_BLT_S); mono_mb_emit_exception (mb, "OutOfMemoryException", NULL); mono_mb_patch_short_branch (mb, pos_error); mono_mb_emit_exception (mb, "OverflowException", NULL); mono_mb_patch_short_branch (mb, pos); clause = mono_image_alloc0 (mono_defaults.corlib, sizeof (MonoExceptionClause)); clause->try_offset = mono_mb_get_label (mb); /* vtable->klass->sizes.element_size */ mono_mb_emit_ldarg (mb, 0); mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoVTable, klass)); mono_mb_emit_byte (mb, CEE_ADD); mono_mb_emit_byte (mb, CEE_LDIND_I); mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoClass, sizes.element_size)); mono_mb_emit_byte (mb, CEE_ADD); mono_mb_emit_byte (mb, CEE_LDIND_U4); mono_mb_emit_byte (mb, CEE_CONV_I); /* * n */ mono_mb_emit_ldarg (mb, 1); mono_mb_emit_byte (mb, CEE_MUL_OVF_UN); /* + sizeof (MonoArray) */ mono_mb_emit_icon (mb, sizeof (MonoArray)); mono_mb_emit_byte (mb, CEE_ADD_OVF_UN); mono_mb_emit_stloc (mb, size_var); pos_leave = mono_mb_emit_branch (mb, CEE_LEAVE); /* catch */ clause->flags = MONO_EXCEPTION_CLAUSE_NONE; clause->try_len = mono_mb_get_pos (mb) - clause->try_offset; clause->data.catch_class = mono_class_from_name (mono_defaults.corlib, "System", "OverflowException"); g_assert (clause->data.catch_class); clause->handler_offset = mono_mb_get_label (mb); oom_exc_class = mono_class_from_name (mono_defaults.corlib, "System", "OutOfMemoryException"); g_assert (oom_exc_class); ctor = mono_class_get_method_from_name (oom_exc_class, ".ctor", 0); g_assert (ctor); mono_mb_emit_byte (mb, CEE_POP); mono_mb_emit_op (mb, CEE_NEWOBJ, ctor); mono_mb_emit_byte (mb, CEE_THROW); clause->handler_len = mono_mb_get_pos (mb) - clause->handler_offset; mono_mb_set_clauses (mb, 1, clause); mono_mb_patch_branch (mb, pos_leave); /* end catch */ } else if (atype == ATYPE_STRING) { int pos; /* * a string allocator method takes the args: (vtable, len) * * bytes = sizeof (MonoString) + ((len + 1) * 2) * * condition: * * bytes <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1) * * therefore: * * sizeof (MonoString) + ((len + 1) * 2) <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1) * len <= (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - sizeof (MonoString)) / 2 - 1 */ mono_mb_emit_ldarg (mb, 1); mono_mb_emit_icon (mb, (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - sizeof (MonoString)) / 2 - 1); pos = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S); mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX); mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN); mono_mb_emit_exception (mb, "OutOfMemoryException", NULL); mono_mb_patch_short_branch (mb, pos); mono_mb_emit_ldarg (mb, 1); mono_mb_emit_icon (mb, 1); mono_mb_emit_byte (mb, MONO_CEE_SHL); //WE manually fold the above + 2 here mono_mb_emit_icon (mb, sizeof (MonoString) + 2); mono_mb_emit_byte (mb, CEE_ADD); mono_mb_emit_stloc (mb, size_var); } else { g_assert_not_reached (); } /* size += ALLOC_ALIGN - 1; */ mono_mb_emit_ldloc (mb, size_var); mono_mb_emit_icon (mb, ALLOC_ALIGN - 1); mono_mb_emit_byte (mb, CEE_ADD); /* size &= ~(ALLOC_ALIGN - 1); */ mono_mb_emit_icon (mb, ~(ALLOC_ALIGN - 1)); mono_mb_emit_byte (mb, CEE_AND); mono_mb_emit_stloc (mb, size_var); /* if (size > MAX_SMALL_OBJ_SIZE) goto slowpath */ if (atype != ATYPE_SMALL) { mono_mb_emit_ldloc (mb, size_var); mono_mb_emit_icon (mb, MAX_SMALL_OBJ_SIZE); max_size_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S); } /* * We need to modify tlab_next, but the JIT only supports reading, so we read * another tls var holding its address instead. */ /* tlab_next_addr (local) = tlab_next_addr (TLS var) */ tlab_next_addr_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg); EMIT_TLS_ACCESS (mb, tlab_next_addr, TLS_KEY_SGEN_TLAB_NEXT_ADDR); mono_mb_emit_stloc (mb, tlab_next_addr_var); /* p = (void**)tlab_next; */ p_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg); mono_mb_emit_ldloc (mb, tlab_next_addr_var); mono_mb_emit_byte (mb, CEE_LDIND_I); mono_mb_emit_stloc (mb, p_var); /* new_next = (char*)p + size; */ new_next_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg); mono_mb_emit_ldloc (mb, p_var); mono_mb_emit_ldloc (mb, size_var); mono_mb_emit_byte (mb, CEE_CONV_I); mono_mb_emit_byte (mb, CEE_ADD); mono_mb_emit_stloc (mb, new_next_var); /* if (G_LIKELY (new_next < tlab_temp_end)) */ mono_mb_emit_ldloc (mb, new_next_var); EMIT_TLS_ACCESS (mb, tlab_temp_end, TLS_KEY_SGEN_TLAB_TEMP_END); slowpath_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S); /* Slowpath */ if (atype != ATYPE_SMALL) mono_mb_patch_short_branch (mb, max_size_branch); mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX); mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN); /* FIXME: mono_gc_alloc_obj takes a 'size_t' as an argument, not an int32 */ mono_mb_emit_ldarg (mb, 0); mono_mb_emit_ldloc (mb, size_var); if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) { mono_mb_emit_icall (mb, mono_gc_alloc_obj); } else if (atype == ATYPE_VECTOR) { mono_mb_emit_ldarg (mb, 1); mono_mb_emit_icall (mb, mono_gc_alloc_vector); } else if (atype == ATYPE_STRING) { mono_mb_emit_ldarg (mb, 1); mono_mb_emit_icall (mb, mono_gc_alloc_string); } else { g_assert_not_reached (); } mono_mb_emit_byte (mb, CEE_RET); /* Fastpath */ mono_mb_patch_short_branch (mb, slowpath_branch); /* FIXME: Memory barrier */ /* tlab_next = new_next */ mono_mb_emit_ldloc (mb, tlab_next_addr_var); mono_mb_emit_ldloc (mb, new_next_var); mono_mb_emit_byte (mb, CEE_STIND_I); /*The tlab store must be visible before the the vtable store. This could be replaced with a DDS but doing it with IL would be tricky. */ mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); mono_mb_emit_op (mb, CEE_MONO_MEMORY_BARRIER, (gpointer)StoreStoreBarrier); /* *p = vtable; */ mono_mb_emit_ldloc (mb, p_var); mono_mb_emit_ldarg (mb, 0); mono_mb_emit_byte (mb, CEE_STIND_I); if (atype == ATYPE_VECTOR) { /* arr->max_length = max_length; */ mono_mb_emit_ldloc (mb, p_var); mono_mb_emit_ldflda (mb, G_STRUCT_OFFSET (MonoArray, max_length)); mono_mb_emit_ldarg (mb, 1); #ifdef MONO_BIG_ARRAYS mono_mb_emit_byte (mb, CEE_STIND_I); #else mono_mb_emit_byte (mb, CEE_STIND_I4); #endif } else if (atype == ATYPE_STRING) { /* need to set length and clear the last char */ /* s->length = len; */ mono_mb_emit_ldloc (mb, p_var); mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoString, length)); mono_mb_emit_byte (mb, MONO_CEE_ADD); mono_mb_emit_ldarg (mb, 1); mono_mb_emit_byte (mb, MONO_CEE_STIND_I4); /* s->chars [len] = 0; */ mono_mb_emit_ldloc (mb, p_var); mono_mb_emit_ldloc (mb, size_var); mono_mb_emit_icon (mb, 2); mono_mb_emit_byte (mb, MONO_CEE_SUB); mono_mb_emit_byte (mb, MONO_CEE_ADD); mono_mb_emit_icon (mb, 0); mono_mb_emit_byte (mb, MONO_CEE_STIND_I2); } /* We must make sure both vtable and max_length are globaly visible before returning to managed land. */ mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); mono_mb_emit_op (mb, CEE_MONO_MEMORY_BARRIER, (gpointer)StoreStoreBarrier); /* return p */ mono_mb_emit_ldloc (mb, p_var); mono_mb_emit_byte (mb, CEE_RET); #endif res = mono_mb_create_method (mb, csig, 8); mono_mb_free (mb); mono_method_get_header (res)->init_locals = FALSE; info = mono_image_alloc0 (mono_defaults.corlib, sizeof (AllocatorWrapperInfo)); info->gc_name = "sgen"; info->alloc_type = atype; mono_marshal_set_wrapper_info (res, info); return res; }