// This part of YJIT helps interfacing with the rest of CRuby and with the OS. // Sometimes our FFI binding generation tool gives undesirable outputs when it // sees C features that Rust doesn't support well. We mitigate that by binding // functions which have simple parameter types. The boilerplate C functions for // that purpose are in this file. // Similarly, we wrap OS facilities we need in simple functions to help with // FFI and to avoid the need to use external crates.io Rust libraries. #include "internal.h" #include "internal/sanitizers.h" #include "internal/string.h" #include "internal/hash.h" #include "internal/variable.h" #include "internal/compile.h" #include "internal/class.h" #include "gc.h" #include "vm_core.h" #include "vm_callinfo.h" #include "builtin.h" #include "insns.inc" #include "insns_info.inc" #include "vm_sync.h" #include "yjit.h" #include "vm_insnhelper.h" #include "probes.h" #include "probes_helper.h" #include "iseq.h" // For mmapp(), sysconf() #ifndef _WIN32 #include #include #endif #include // We need size_t to have a known size to simplify code generation and FFI. // TODO(alan): check this in configure.ac to fail fast on 32 bit platforms. STATIC_ASSERT(64b_size_t, SIZE_MAX == UINT64_MAX); // I don't know any C implementation that has uint64_t and puts padding bits // into size_t but the standard seems to allow it. STATIC_ASSERT(size_t_no_padding_bits, sizeof(size_t) == sizeof(uint64_t)); // This build config impacts the pointer tagging scheme and we only want to // support one scheme for simplicity. STATIC_ASSERT(pointer_tagging_scheme, USE_FLONUM); // NOTE: We can trust that uint8_t has no "padding bits" since the C spec // guarantees it. Wording about padding bits is more explicit in C11 compared // to C99. See C11 7.20.1.1p2. All this is to say we have _some_ standards backing to // use a Rust `*mut u8` to represent a C `uint8_t *`. // // If we don't want to trust that we can interpreter the C standard correctly, we // could outsource that work to the Rust standard library by sticking to fundamental // types in C such as int, long, etc. and use `std::os::raw::c_long` and friends on // the Rust side. // // What's up with the long prefix? The "rb_" part is to apease `make leaked-globals` // which runs on upstream CI. The rationale for the check is unclear to Alan as // we build with `-fvisibility=hidden` so only explicitly marked functions end // up as public symbols in libruby.so. Perhaps the check is for the static // libruby and or general namspacing hygiene? Alan admits his bias towards ELF // platforms and newer compilers. // // The "_yjit_" part is for trying to be informative. We might want different // suffixes for symbols meant for Rust and symbols meant for broader CRuby. void rb_yjit_mark_writable(void *mem_block, uint32_t mem_size) { if (mprotect(mem_block, mem_size, PROT_READ | PROT_WRITE)) { rb_bug("Couldn't make JIT page region (%p, %lu bytes) writeable, errno: %s\n", mem_block, (unsigned long)mem_size, strerror(errno)); } } void rb_yjit_mark_executable(void *mem_block, uint32_t mem_size) { if (mprotect(mem_block, mem_size, PROT_READ | PROT_EXEC)) { rb_bug("Couldn't make JIT page (%p, %lu bytes) executable, errno: %s\n", mem_block, (unsigned long)mem_size, strerror(errno)); } } uint32_t rb_yjit_get_page_size(void) { #if defined(_SC_PAGESIZE) long page_size = sysconf(_SC_PAGESIZE); if (page_size <= 0) rb_bug("yjit: failed to get page size"); // 1 GiB limit. x86 CPUs with PDPE1GB can do this and anything larger is unexpected. // Though our design sort of assume we have fine grained control over memory protection // which require small page sizes. if (page_size > 0x40000000l) rb_bug("yjit page size too large"); return (uint32_t)page_size; #else #error "YJIT supports POSIX only for now" #endif } #if defined(MAP_FIXED_NOREPLACE) && defined(_SC_PAGESIZE) // Align the current write position to a multiple of bytes static uint8_t * align_ptr(uint8_t *ptr, uint32_t multiple) { // Compute the pointer modulo the given alignment boundary uint32_t rem = ((uint32_t)(uintptr_t)ptr) % multiple; // If the pointer is already aligned, stop if (rem == 0) return ptr; // Pad the pointer by the necessary amount to align it uint32_t pad = multiple - rem; return ptr + pad; } #endif // Allocate a block of executable memory uint8_t * rb_yjit_alloc_exec_mem(uint32_t mem_size) { #ifndef _WIN32 uint8_t *mem_block; // On Linux #if defined(MAP_FIXED_NOREPLACE) && defined(_SC_PAGESIZE) // Align the requested address to page size uint32_t page_size = (uint32_t)sysconf(_SC_PAGESIZE); uint8_t *req_addr = align_ptr((uint8_t*)&rb_yjit_alloc_exec_mem, page_size); do { // Try to map a chunk of memory as executable mem_block = (uint8_t*)mmap( (void*)req_addr, mem_size, PROT_READ | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED_NOREPLACE, -1, 0 ); // If we succeeded, stop if (mem_block != MAP_FAILED) { break; } // +4MB req_addr += 4 * 1024 * 1024; } while (req_addr < (uint8_t*)&rb_yjit_alloc_exec_mem + INT32_MAX); // On MacOS and other platforms #else // Try to map a chunk of memory as executable mem_block = (uint8_t*)mmap( (void*)rb_yjit_alloc_exec_mem, mem_size, PROT_READ | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0 ); #endif // Fallback if (mem_block == MAP_FAILED) { // Try again without the address hint (e.g., valgrind) mem_block = (uint8_t*)mmap( NULL, mem_size, PROT_READ | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0 ); } // Check that the memory mapping was successful if (mem_block == MAP_FAILED) { perror("mmap call failed"); exit(-1); } // Fill the executable memory with PUSH DS (0x1E) so that // executing uninitialized memory will fault with #UD in // 64-bit mode. rb_yjit_mark_writable(mem_block, mem_size); memset(mem_block, 0x1E, mem_size); rb_yjit_mark_executable(mem_block, mem_size); return mem_block; #else // Windows not supported for now return NULL; #endif } // Is anyone listening for :c_call and :c_return event currently? bool rb_c_method_tracing_currently_enabled(rb_execution_context_t *ec) { rb_event_flag_t tracing_events; if (rb_multi_ractor_p()) { tracing_events = ruby_vm_event_enabled_global_flags; } else { // At the time of writing, events are never removed from // ruby_vm_event_enabled_global_flags so always checking using it would // mean we don't compile even after tracing is disabled. tracing_events = rb_ec_ractor_hooks(ec)->events; } return tracing_events & (RUBY_EVENT_C_CALL | RUBY_EVENT_C_RETURN); } // The code we generate in gen_send_cfunc() doesn't fire the c_return TracePoint event // like the interpreter. When tracing for c_return is enabled, we patch the code after // the C method return to call into this to fire the event. void rb_full_cfunc_return(rb_execution_context_t *ec, VALUE return_value) { rb_control_frame_t *cfp = ec->cfp; RUBY_ASSERT_ALWAYS(cfp == GET_EC()->cfp); const rb_callable_method_entry_t *me = rb_vm_frame_method_entry(cfp); RUBY_ASSERT_ALWAYS(RUBYVM_CFUNC_FRAME_P(cfp)); RUBY_ASSERT_ALWAYS(me->def->type == VM_METHOD_TYPE_CFUNC); // CHECK_CFP_CONSISTENCY("full_cfunc_return"); TODO revive this // Pop the C func's frame and fire the c_return TracePoint event // Note that this is the same order as vm_call_cfunc_with_frame(). rb_vm_pop_frame(ec); EXEC_EVENT_HOOK(ec, RUBY_EVENT_C_RETURN, cfp->self, me->def->original_id, me->called_id, me->owner, return_value); // Note, this deviates from the interpreter in that users need to enable // a c_return TracePoint for this DTrace hook to work. A reasonable change // since the Ruby return event works this way as well. RUBY_DTRACE_CMETHOD_RETURN_HOOK(ec, me->owner, me->def->original_id); // Push return value into the caller's stack. We know that it's a frame that // uses cfp->sp because we are patching a call done with gen_send_cfunc(). ec->cfp->sp[0] = return_value; ec->cfp->sp++; } unsigned int rb_iseq_encoded_size(const rb_iseq_t *iseq) { return iseq->body->iseq_size; } // TODO(alan): consider using an opaque pointer for the payload rather than a void pointer void * rb_iseq_get_yjit_payload(const rb_iseq_t *iseq) { RUBY_ASSERT_ALWAYS(IMEMO_TYPE_P(iseq, imemo_iseq)); if (iseq->body) { return iseq->body->yjit_payload; } else { // Body is NULL when constructing the iseq. return NULL; } } void rb_iseq_set_yjit_payload(const rb_iseq_t *iseq, void *payload) { RUBY_ASSERT_ALWAYS(IMEMO_TYPE_P(iseq, imemo_iseq)); RUBY_ASSERT_ALWAYS(iseq->body); RUBY_ASSERT_ALWAYS(NULL == iseq->body->yjit_payload); iseq->body->yjit_payload = payload; } void rb_iseq_reset_jit_func(const rb_iseq_t *iseq) { RUBY_ASSERT_ALWAYS(IMEMO_TYPE_P(iseq, imemo_iseq)); iseq->body->jit_func = NULL; } // Get the PC for a given index in an iseq VALUE * rb_iseq_pc_at_idx(const rb_iseq_t *iseq, uint32_t insn_idx) { RUBY_ASSERT_ALWAYS(IMEMO_TYPE_P(iseq, imemo_iseq)); RUBY_ASSERT_ALWAYS(insn_idx < iseq->body->iseq_size); VALUE *encoded = iseq->body->iseq_encoded; VALUE *pc = &encoded[insn_idx]; return pc; } // Get the opcode given a program counter. Can return trace opcode variants. int rb_iseq_opcode_at_pc(const rb_iseq_t *iseq, const VALUE *pc) { // YJIT should only use iseqs after AST to bytecode compilation RUBY_ASSERT_ALWAYS(FL_TEST_RAW((VALUE)iseq, ISEQ_TRANSLATED)); const VALUE at_pc = *pc; return rb_vm_insn_addr2opcode((const void *)at_pc); } // used by jit_rb_str_bytesize in codegen.rs VALUE rb_str_bytesize(VALUE str) { return LONG2NUM(RSTRING_LEN(str)); } // This is defined only as a named struct inside rb_iseq_constant_body. // By giving it a separate typedef, we make it nameable by rust-bindgen. // Bindgen's temp/anon name isn't guaranteed stable. typedef struct rb_iseq_param_keyword rb_seq_param_keyword_struct; const char * rb_insn_name(VALUE insn) { return insn_name(insn); } // Query the instruction length in bytes for YARV opcode insn int rb_insn_len(VALUE insn) { return insn_len(insn); } unsigned int rb_vm_ci_argc(const struct rb_callinfo *ci) { return vm_ci_argc(ci); } ID rb_vm_ci_mid(const struct rb_callinfo *ci) { return vm_ci_mid(ci); } unsigned int rb_vm_ci_flag(const struct rb_callinfo *ci) { return vm_ci_flag(ci); } const struct rb_callinfo_kwarg * rb_vm_ci_kwarg(const struct rb_callinfo *ci) { return vm_ci_kwarg(ci); } int rb_get_cikw_keyword_len(const struct rb_callinfo_kwarg *cikw) { return cikw->keyword_len; } VALUE rb_get_cikw_keywords_idx(const struct rb_callinfo_kwarg *cikw, int idx) { return cikw->keywords[idx]; } rb_method_visibility_t rb_METHOD_ENTRY_VISI(rb_callable_method_entry_t *me) { return METHOD_ENTRY_VISI(me); } rb_method_type_t rb_get_cme_def_type(rb_callable_method_entry_t *cme) { return cme->def->type; } ID rb_get_cme_def_body_attr_id(rb_callable_method_entry_t *cme) { return cme->def->body.attr.id; } enum method_optimized_type rb_get_cme_def_body_optimized_type(rb_callable_method_entry_t *cme) { return cme->def->body.optimized.type; } unsigned int rb_get_cme_def_body_optimized_index(rb_callable_method_entry_t *cme) { return cme->def->body.optimized.index; } rb_method_cfunc_t * rb_get_cme_def_body_cfunc(rb_callable_method_entry_t *cme) { return UNALIGNED_MEMBER_PTR(cme->def, body.cfunc); } uintptr_t rb_get_def_method_serial(rb_method_definition_t *def) { return def->method_serial; } ID rb_get_def_original_id(rb_method_definition_t *def) { return def->original_id; } int rb_get_mct_argc(rb_method_cfunc_t *mct) { return mct->argc; } void * rb_get_mct_func(rb_method_cfunc_t *mct) { return (void*)mct->func; // this field is defined as type VALUE (*func)(ANYARGS) } const rb_iseq_t * rb_get_def_iseq_ptr(rb_method_definition_t *def) { return def_iseq_ptr(def); } rb_iseq_t * rb_get_iseq_body_local_iseq(rb_iseq_t *iseq) { return iseq->body->local_iseq; } unsigned int rb_get_iseq_body_local_table_size(rb_iseq_t *iseq) { return iseq->body->local_table_size; } VALUE * rb_get_iseq_body_iseq_encoded(rb_iseq_t *iseq) { return iseq->body->iseq_encoded; } bool rb_get_iseq_body_builtin_inline_p(rb_iseq_t *iseq) { return iseq->body->builtin_inline_p; } unsigned rb_get_iseq_body_stack_max(rb_iseq_t *iseq) { return iseq->body->stack_max; } bool rb_get_iseq_flags_has_opt(rb_iseq_t *iseq) { return iseq->body->param.flags.has_opt; } bool rb_get_iseq_flags_has_kw(rb_iseq_t *iseq) { return iseq->body->param.flags.has_kw; } bool rb_get_iseq_flags_has_post(rb_iseq_t *iseq) { return iseq->body->param.flags.has_post; } bool rb_get_iseq_flags_has_kwrest(rb_iseq_t *iseq) { return iseq->body->param.flags.has_kwrest; } bool rb_get_iseq_flags_has_rest(rb_iseq_t *iseq) { return iseq->body->param.flags.has_rest; } bool rb_get_iseq_flags_has_block(rb_iseq_t *iseq) { return iseq->body->param.flags.has_block; } bool rb_get_iseq_flags_has_accepts_no_kwarg(rb_iseq_t *iseq) { return iseq->body->param.flags.accepts_no_kwarg; } const rb_seq_param_keyword_struct * rb_get_iseq_body_param_keyword(rb_iseq_t *iseq) { return iseq->body->param.keyword; } unsigned rb_get_iseq_body_param_size(rb_iseq_t *iseq) { return iseq->body->param.size; } int rb_get_iseq_body_param_lead_num(rb_iseq_t *iseq) { return iseq->body->param.lead_num; } int rb_get_iseq_body_param_opt_num(rb_iseq_t *iseq) { return iseq->body->param.opt_num; } const VALUE * rb_get_iseq_body_param_opt_table(rb_iseq_t *iseq) { return iseq->body->param.opt_table; } // If true, the iseq is leaf and it can be replaced by a single C call. bool rb_leaf_invokebuiltin_iseq_p(const rb_iseq_t *iseq) { unsigned int invokebuiltin_len = insn_len(BIN(opt_invokebuiltin_delegate_leave)); unsigned int leave_len = insn_len(BIN(leave)); return (iseq->body->iseq_size == (invokebuiltin_len + leave_len) && rb_vm_insn_addr2opcode((void *)iseq->body->iseq_encoded[0]) == BIN(opt_invokebuiltin_delegate_leave) && rb_vm_insn_addr2opcode((void *)iseq->body->iseq_encoded[invokebuiltin_len]) == BIN(leave) && iseq->body->builtin_inline_p ); } // Return an rb_builtin_function if the iseq contains only that leaf builtin function. const struct rb_builtin_function * rb_leaf_builtin_function(const rb_iseq_t *iseq) { if (!rb_leaf_invokebuiltin_iseq_p(iseq)) return NULL; return (const struct rb_builtin_function *)iseq->body->iseq_encoded[1]; } struct rb_control_frame_struct * rb_get_ec_cfp(rb_execution_context_t *ec) { return ec->cfp; } VALUE * rb_get_cfp_pc(struct rb_control_frame_struct *cfp) { return (VALUE*)cfp->pc; } VALUE * rb_get_cfp_sp(struct rb_control_frame_struct *cfp) { return cfp->sp; } void rb_set_cfp_pc(struct rb_control_frame_struct *cfp, const VALUE *pc) { cfp->pc = pc; } void rb_set_cfp_sp(struct rb_control_frame_struct *cfp, VALUE *sp) { cfp->sp = sp; } rb_iseq_t * rb_cfp_get_iseq(struct rb_control_frame_struct *cfp) { // TODO(alan) could assert frame type here to make sure that it's a ruby frame with an iseq. return (rb_iseq_t*)cfp->iseq; } VALUE rb_get_cfp_self(struct rb_control_frame_struct *cfp) { return cfp->self; } VALUE * rb_get_cfp_ep(struct rb_control_frame_struct *cfp) { return (VALUE*)cfp->ep; } VALUE rb_yarv_class_of(VALUE obj) { return rb_class_of(obj); } // YJIT needs this function to never allocate and never raise VALUE rb_yarv_str_eql_internal(VALUE str1, VALUE str2) { // We wrap this since it's static inline return rb_str_eql_internal(str1, str2); } // YJIT needs this function to never allocate and never raise VALUE rb_yarv_ary_entry_internal(VALUE ary, long offset) { return rb_ary_entry_internal(ary, offset); } // Print the Ruby source location of some ISEQ for debugging purposes void rb_yjit_dump_iseq_loc(const rb_iseq_t *iseq, uint32_t insn_idx) { char *ptr; long len; VALUE path = rb_iseq_path(iseq); RSTRING_GETMEM(path, ptr, len); fprintf(stderr, "%s %.*s:%u\n", __func__, (int)len, ptr, rb_iseq_line_no(iseq, insn_idx)); } // The FL_TEST() macro VALUE rb_FL_TEST(VALUE obj, VALUE flags) { return RB_FL_TEST(obj, flags); } // The FL_TEST_RAW() macro, normally an internal implementation detail VALUE rb_FL_TEST_RAW(VALUE obj, VALUE flags) { return FL_TEST_RAW(obj, flags); } // The RB_TYPE_P macro bool rb_RB_TYPE_P(VALUE obj, enum ruby_value_type t) { return RB_TYPE_P(obj, t); } long rb_RSTRUCT_LEN(VALUE st) { return RSTRUCT_LEN(st); } // There are RSTRUCT_SETs in ruby/internal/core/rstruct.h and internal/struct.h // with different types (int vs long) for k. Here we use the one from ruby/internal/core/rstruct.h, // which takes an int. void rb_RSTRUCT_SET(VALUE st, int k, VALUE v) { RSTRUCT_SET(st, k, v); } const struct rb_callinfo * rb_get_call_data_ci(struct rb_call_data *cd) { return cd->ci; } bool rb_BASIC_OP_UNREDEFINED_P(enum ruby_basic_operators bop, uint32_t klass) { return BASIC_OP_UNREDEFINED_P(bop, klass); } VALUE rb_RCLASS_ORIGIN(VALUE c) { return RCLASS_ORIGIN(c); } bool rb_yjit_multi_ractor_p(void) { return rb_multi_ractor_p(); } // For debug builds void rb_assert_iseq_handle(VALUE handle) { RUBY_ASSERT_ALWAYS(rb_objspace_markable_object_p(handle)); RUBY_ASSERT_ALWAYS(IMEMO_TYPE_P(handle, imemo_iseq)); } int rb_IMEMO_TYPE_P(VALUE imemo, enum imemo_type imemo_type) { return IMEMO_TYPE_P(imemo, imemo_type); } void rb_assert_cme_handle(VALUE handle) { RUBY_ASSERT_ALWAYS(rb_objspace_markable_object_p(handle)); RUBY_ASSERT_ALWAYS(IMEMO_TYPE_P(handle, imemo_ment)); } typedef void (*iseq_callback)(const rb_iseq_t *); // Heap-walking callback for rb_yjit_for_each_iseq(). static int for_each_iseq_i(void *vstart, void *vend, size_t stride, void *data) { const iseq_callback callback = (iseq_callback)data; VALUE v = (VALUE)vstart; for (; v != (VALUE)vend; v += stride) { void *ptr = asan_poisoned_object_p(v); asan_unpoison_object(v, false); if (rb_obj_is_iseq(v)) { rb_iseq_t *iseq = (rb_iseq_t *)v; callback(iseq); } asan_poison_object_if(ptr, v); } return 0; } // Iterate through the whole GC heap and invoke a callback for each iseq. // Used for global code invalidation. void rb_yjit_for_each_iseq(iseq_callback callback) { rb_objspace_each_objects(for_each_iseq_i, (void *)callback); } // For running write barriers from Rust. Required when we add a new edge in the // object graph from `old` to `young`. void rb_yjit_obj_written(VALUE old, VALUE young, const char *file, int line) { rb_obj_written(old, Qundef, young, file, line); } // Acquire the VM lock and then signal all other Ruby threads (ractors) to // contend for the VM lock, putting them to sleep. YJIT uses this to evict // threads running inside generated code so among other things, it can // safely change memory protection of regions housing generated code. void rb_yjit_vm_lock_then_barrier(unsigned int *recursive_lock_level, const char *file, int line) { rb_vm_lock_enter(recursive_lock_level, file, line); rb_vm_barrier(); } // Release the VM lock. The lock level must point to the same integer used to // acquire the lock. void rb_yjit_vm_unlock(unsigned int *recursive_lock_level, const char *file, int line) { rb_vm_lock_leave(recursive_lock_level, file, line); } // Pointer to a YJIT entry point (machine code generated by YJIT) typedef VALUE (*yjit_func_t)(rb_execution_context_t *, rb_control_frame_t *); bool rb_yjit_compile_iseq(const rb_iseq_t *iseq, rb_execution_context_t *ec) { bool success = true; RB_VM_LOCK_ENTER(); rb_vm_barrier(); // Compile a block version starting at the first instruction uint8_t *rb_yjit_iseq_gen_entry_point(const rb_iseq_t *iseq, rb_execution_context_t *ec); // defined in Rust uint8_t *code_ptr = rb_yjit_iseq_gen_entry_point(iseq, ec); if (code_ptr) { iseq->body->jit_func = (yjit_func_t)code_ptr; } else { iseq->body->jit_func = 0; success = false; } RB_VM_LOCK_LEAVE(); return success; } // GC root for interacting with the GC struct yjit_root_struct { bool unused; // empty structs are not legal in C99 }; static void yjit_root_free(void *ptr) { // Do nothing. The root lives as long as the process. } static size_t yjit_root_memsize(const void *ptr) { // Count off-gc-heap allocation size of the dependency table return 0; // TODO: more accurate accounting } // GC callback during compaction static void yjit_root_update_references(void *ptr) { // Do nothing since we use rb_gc_mark(), which pins. } void rb_yjit_root_mark(void *ptr); // in Rust // Custom type for interacting with the GC // TODO: make this write barrier protected static const rb_data_type_t yjit_root_type = { "yjit_root", {rb_yjit_root_mark, yjit_root_free, yjit_root_memsize, yjit_root_update_references}, 0, 0, RUBY_TYPED_FREE_IMMEDIATELY }; // For dealing with refinements void rb_yjit_invalidate_all_method_lookup_assumptions(void) { // It looks like Module#using actually doesn't need to invalidate all the // method caches, so we do nothing here for now. } // Primitives used by yjit.rb VALUE rb_yjit_stats_enabled_p(rb_execution_context_t *ec, VALUE self); VALUE rb_yjit_get_stats(rb_execution_context_t *ec, VALUE self); VALUE rb_yjit_reset_stats_bang(rb_execution_context_t *ec, VALUE self); VALUE rb_yjit_disasm_iseq(rb_execution_context_t *ec, VALUE self, VALUE iseq); VALUE rb_yjit_insns_compiled(rb_execution_context_t *ec, VALUE self, VALUE iseq); VALUE rb_yjit_simulate_oom_bang(rb_execution_context_t *ec, VALUE self); VALUE rb_yjit_get_stats(rb_execution_context_t *ec, VALUE self); // Preprocessed yjit.rb generated during build #include "yjit.rbinc" // Can raise RuntimeError void rb_yjit_init(void) { // Call the Rust initialization code void rb_yjit_init_rust(void); rb_yjit_init_rust(); // Initialize the GC hooks. Do this second as some code depend on Rust initialization. struct yjit_root_struct *root; VALUE yjit_root = TypedData_Make_Struct(0, struct yjit_root_struct, &yjit_root_type, root); rb_gc_register_mark_object(yjit_root); }