vm_callinfo.h

#ifndef RUBY_VM_CALLINFO_H                               /*-*-C-*-vi:se ft=c:*/
#define RUBY_VM_CALLINFO_H
 
#include "debug_counter.h"
#include "internal/class.h"
#include "shape.h"
 
enum vm_call_flag_bits {
    VM_CALL_ARGS_SPLAT_bit,     // m(*args)
    VM_CALL_ARGS_BLOCKARG_bit,  // m(&block)
    VM_CALL_FCALL_bit,          // m(args)   # receiver is self
    VM_CALL_VCALL_bit,          // m         # method call that looks like a local variable
    VM_CALL_ARGS_SIMPLE_bit,    // !(ci->flag & (SPLAT|BLOCKARG|KWARG|KW_SPLAT|FORWARDING)) && !has_block_iseq
    VM_CALL_KWARG_bit,          // has kwarg
    VM_CALL_KW_SPLAT_bit,       // m(**opts)
    VM_CALL_TAILCALL_bit,       // located at tail position
    VM_CALL_SUPER_bit,          // super
    VM_CALL_ZSUPER_bit,         // zsuper
    VM_CALL_OPT_SEND_bit,       // internal flag
    VM_CALL_KW_SPLAT_MUT_bit,   // kw splat hash can be modified (to avoid allocating a new one)
    VM_CALL_ARGS_SPLAT_MUT_bit, // args splat can be modified (to avoid allocating a new one)
    VM_CALL_FORWARDING_bit,     // m(...)
    VM_CALL__END
};
 
#define VM_CALL_ARGS_SPLAT      (0x01 << VM_CALL_ARGS_SPLAT_bit)
#define VM_CALL_ARGS_BLOCKARG   (0x01 << VM_CALL_ARGS_BLOCKARG_bit)
#define VM_CALL_FCALL           (0x01 << VM_CALL_FCALL_bit)
#define VM_CALL_VCALL           (0x01 << VM_CALL_VCALL_bit)
#define VM_CALL_ARGS_SIMPLE     (0x01 << VM_CALL_ARGS_SIMPLE_bit)
#define VM_CALL_KWARG           (0x01 << VM_CALL_KWARG_bit)
#define VM_CALL_KW_SPLAT        (0x01 << VM_CALL_KW_SPLAT_bit)
#define VM_CALL_TAILCALL        (0x01 << VM_CALL_TAILCALL_bit)
#define VM_CALL_SUPER           (0x01 << VM_CALL_SUPER_bit)
#define VM_CALL_ZSUPER          (0x01 << VM_CALL_ZSUPER_bit)
#define VM_CALL_OPT_SEND        (0x01 << VM_CALL_OPT_SEND_bit)
#define VM_CALL_KW_SPLAT_MUT    (0x01 << VM_CALL_KW_SPLAT_MUT_bit)
#define VM_CALL_ARGS_SPLAT_MUT  (0x01 << VM_CALL_ARGS_SPLAT_MUT_bit)
#define VM_CALL_FORWARDING      (0x01 << VM_CALL_FORWARDING_bit)
 
struct rb_callinfo_kwarg {
    int keyword_len;
    rb_atomic_t references;
    VALUE keywords[];
};
 
static inline size_t
rb_callinfo_kwarg_bytes(int keyword_len)
{
    return rb_size_mul_add_or_raise(
        keyword_len,
        sizeof(VALUE),
        sizeof(struct rb_callinfo_kwarg),
        rb_eRuntimeError);
}
 
static inline void
rb_callinfo_kwarg_retain(struct rb_callinfo_kwarg *kwarg)
{
    if (kwarg) RUBY_ATOMIC_INC(kwarg->references);
}
 
static inline void
rb_callinfo_kwarg_release(struct rb_callinfo_kwarg *kwarg)
{
    if (kwarg && RUBY_ATOMIC_FETCH_SUB(kwarg->references, 1) == 1) {
        ruby_sized_xfree(kwarg, rb_callinfo_kwarg_bytes(kwarg->keyword_len));
    }
}
 
// imemo_callinfo
struct rb_callinfo {
    VALUE flags;
    const struct rb_callinfo_kwarg *kwarg;
    VALUE mid;
    VALUE flag;
    VALUE argc;
};
 
#if !defined(USE_EMBED_CI) || (USE_EMBED_CI+0)
#undef USE_EMBED_CI
#define USE_EMBED_CI 1
#else
#undef USE_EMBED_CI
#define USE_EMBED_CI 0
#endif
 
#if SIZEOF_VALUE == 8
#define CI_EMBED_TAG_bits   1
#define CI_EMBED_ARGC_bits 15
#define CI_EMBED_FLAG_bits 16
#define CI_EMBED_ID_bits   32
#elif SIZEOF_VALUE == 4
#define CI_EMBED_TAG_bits   1
#define CI_EMBED_ARGC_bits  3
#define CI_EMBED_FLAG_bits 13
#define CI_EMBED_ID_bits   15
#endif
 
#if (CI_EMBED_TAG_bits + CI_EMBED_ARGC_bits + CI_EMBED_FLAG_bits + CI_EMBED_ID_bits) != (SIZEOF_VALUE * 8)
#error
#endif
 
#define CI_EMBED_FLAG 0x01
#define CI_EMBED_ARGC_SHFT (CI_EMBED_TAG_bits)
#define CI_EMBED_ARGC_MASK ((((VALUE)1)<<CI_EMBED_ARGC_bits) - 1)
#define CI_EMBED_FLAG_SHFT (CI_EMBED_TAG_bits + CI_EMBED_ARGC_bits)
#define CI_EMBED_FLAG_MASK ((((VALUE)1)<<CI_EMBED_FLAG_bits) - 1)
#define CI_EMBED_ID_SHFT   (CI_EMBED_TAG_bits + CI_EMBED_ARGC_bits + CI_EMBED_FLAG_bits)
#define CI_EMBED_ID_MASK   ((((VALUE)1)<<CI_EMBED_ID_bits) - 1)
 
static inline bool
vm_ci_packed_p(const struct rb_callinfo *ci)
{
    if (!USE_EMBED_CI) {
        return 0;
    }
    if (LIKELY(((VALUE)ci) & 0x01)) {
        return 1;
    }
    else {
        VM_ASSERT(IMEMO_TYPE_P(ci, imemo_callinfo));
        return 0;
    }
}
 
static inline bool
vm_ci_p(const struct rb_callinfo *ci)
{
    if (vm_ci_packed_p(ci) || IMEMO_TYPE_P(ci, imemo_callinfo)) {
        return 1;
    }
    else {
        return 0;
    }
}
 
static inline ID
vm_ci_mid(const struct rb_callinfo *ci)
{
    if (vm_ci_packed_p(ci)) {
        return (((VALUE)ci) >> CI_EMBED_ID_SHFT) & CI_EMBED_ID_MASK;
    }
    else {
        return (ID)ci->mid;
    }
}
 
static inline unsigned int
vm_ci_flag(const struct rb_callinfo *ci)
{
    if (vm_ci_packed_p(ci)) {
        return (unsigned int)((((VALUE)ci) >> CI_EMBED_FLAG_SHFT) & CI_EMBED_FLAG_MASK);
    }
    else {
        return (unsigned int)ci->flag;
    }
}
 
static inline unsigned int
vm_ci_argc(const struct rb_callinfo *ci)
{
    if (vm_ci_packed_p(ci)) {
        return (unsigned int)((((VALUE)ci) >> CI_EMBED_ARGC_SHFT) & CI_EMBED_ARGC_MASK);
    }
    else {
        return (unsigned int)ci->argc;
    }
}
 
static inline const struct rb_callinfo_kwarg *
vm_ci_kwarg(const struct rb_callinfo *ci)
{
    if (vm_ci_packed_p(ci)) {
        return NULL;
    }
    else {
        return ci->kwarg;
    }
}
 
static inline void
vm_ci_dump(const struct rb_callinfo *ci)
{
    if (vm_ci_packed_p(ci)) {
        ruby_debug_printf("packed_ci ID:%s flag:%x argc:%u\n",
                          rb_id2name(vm_ci_mid(ci)), vm_ci_flag(ci), vm_ci_argc(ci));
    }
    else {
        rp(ci);
    }
}
 
#define vm_ci_new(mid, flag, argc, kwarg) vm_ci_new_(mid, flag, argc, kwarg, __FILE__, __LINE__)
#define vm_ci_new_runtime(mid, flag, argc, kwarg) vm_ci_new_runtime_(mid, flag, argc, kwarg, __FILE__, __LINE__)
 
/* This is passed to STATIC_ASSERT.  Cannot be an inline function. */
#define VM_CI_EMBEDDABLE_P(mid, flag, argc, kwarg) \
    (((mid ) & ~CI_EMBED_ID_MASK)   ? false :      \
     ((flag) & ~CI_EMBED_FLAG_MASK) ? false :      \
     ((argc) & ~CI_EMBED_ARGC_MASK) ? false :      \
      (kwarg)                       ? false : true)
 
#define vm_ci_new_id(mid, flag, argc, must_zero) \
    ((const struct rb_callinfo *)                \
     ((((VALUE)(mid )) << CI_EMBED_ID_SHFT)   |  \
      (((VALUE)(flag)) << CI_EMBED_FLAG_SHFT) |  \
      (((VALUE)(argc)) << CI_EMBED_ARGC_SHFT) |  \
      RUBY_FIXNUM_FLAG))
 
// vm_method.c
const struct rb_callinfo *rb_vm_ci_lookup(ID mid, unsigned int flag, unsigned int argc, const struct rb_callinfo_kwarg *kwarg);
void rb_vm_ci_free(const struct rb_callinfo *);
 
static inline const struct rb_callinfo *
vm_ci_new_(ID mid, unsigned int flag, unsigned int argc, const struct rb_callinfo_kwarg *kwarg, const char *file, int line)
{
    if (USE_EMBED_CI && VM_CI_EMBEDDABLE_P(mid, flag, argc, kwarg)) {
        RB_DEBUG_COUNTER_INC(ci_packed);
        return vm_ci_new_id(mid, flag, argc, kwarg);
    }
 
    const bool debug = 0;
    if (debug) ruby_debug_printf("%s:%d ", file, line);
 
    const struct rb_callinfo *ci = rb_vm_ci_lookup(mid, flag, argc, kwarg);
 
    if (debug) rp(ci);
    if (kwarg) {
        RB_DEBUG_COUNTER_INC(ci_kw);
    }
    else {
        RB_DEBUG_COUNTER_INC(ci_nokw);
    }
 
    VM_ASSERT(vm_ci_flag(ci) == flag);
    VM_ASSERT(vm_ci_argc(ci) == argc);
 
    return ci;
}
 
 
static inline const struct rb_callinfo *
vm_ci_new_runtime_(ID mid, unsigned int flag, unsigned int argc, const struct rb_callinfo_kwarg *kwarg, const char *file, int line)
{
    RB_DEBUG_COUNTER_INC(ci_runtime);
    return vm_ci_new_(mid, flag, argc, kwarg, file, line);
}
 
#define VM_CALLINFO_NOT_UNDER_GC IMEMO_FL_USER0
 
static inline bool
vm_ci_markable(const struct rb_callinfo *ci)
{
    if (! ci) {
        return false; /* or true? This is Qfalse... */
    }
    else if (vm_ci_packed_p(ci)) {
        return true;
    }
    else {
        VM_ASSERT(IMEMO_TYPE_P(ci, imemo_callinfo));
        return ! FL_ANY_RAW((VALUE)ci, VM_CALLINFO_NOT_UNDER_GC);
    }
}
 
#define VM_CI_ON_STACK(mid_, flags_, argc_, kwarg_) \
    (struct rb_callinfo) {                          \
        .flags = T_IMEMO |                          \
            (imemo_callinfo << FL_USHIFT) |         \
            VM_CALLINFO_NOT_UNDER_GC,               \
        .mid   = mid_,                              \
        .flag  = flags_,                            \
        .argc  = argc_,                             \
        .kwarg = kwarg_,                            \
    }
 
typedef VALUE (*vm_call_handler)(
    struct rb_execution_context_struct *ec,
    struct rb_control_frame_struct *cfp,
    struct rb_calling_info *calling);
 
// imemo_callcache
 
struct rb_callcache {
    const VALUE flags;
 
    /* inline cache: key */
    const VALUE klass; // Weak reference. When klass is collected, `cc->klass = Qundef`.
 
    /* inline cache: values */
    const struct rb_callable_method_entry_struct * const cme_;
    const vm_call_handler call_;
 
    union {
        struct {
            uint64_t value; // Shape ID in former half, index in latter half
        } attr;
        const enum method_missing_reason method_missing_reason; /* used by method_missing */
        VALUE v;
        const struct rb_builtin_function *bf;
    } aux_;
};
 
/* VM_CALLCACHE_IVAR used for IVAR/ATTRSET/STRUCT_AREF/STRUCT_ASET methods */
#define VM_CALLCACHE_IVAR       IMEMO_FL_USER0
#define VM_CALLCACHE_BF         IMEMO_FL_USER1
#define VM_CALLCACHE_SUPER      IMEMO_FL_USER2
#define VM_CALLCACHE_REFINEMENT IMEMO_FL_USER3
#define VM_CALLCACHE_UNMARKABLE IMEMO_FL_USER4
#define VM_CALLCACHE_ON_STACK   IMEMO_FL_USER5
#define VM_CALLCACHE_INVALID_SUPER IMEMO_FL_USER6
 
enum vm_cc_type {
    cc_type_normal, // chained from ccs
    cc_type_super,
    cc_type_refinement,
};
 
extern const struct rb_callcache *rb_vm_empty_cc(void);
extern const struct rb_callcache *rb_vm_empty_cc_for_super(void);
 
#define vm_cc_empty() rb_vm_empty_cc()
 
static inline void vm_cc_attr_index_set(const struct rb_callcache *cc, attr_index_t index, shape_id_t dest_shape_id);
 
static inline void
vm_cc_attr_index_initialize(const struct rb_callcache *cc, shape_id_t shape_id)
{
    vm_cc_attr_index_set(cc, (attr_index_t)-1, shape_id);
}
 
static inline VALUE
cc_check_class(VALUE klass)
{
    VM_ASSERT(klass == Qundef || RB_TYPE_P(klass, T_CLASS) || RB_TYPE_P(klass, T_ICLASS));
    return klass;
}
 
VALUE rb_vm_cc_table_create(size_t capa);
VALUE rb_vm_cc_table_dup(VALUE old_table);
void rb_vm_cc_table_delete(VALUE table, ID mid);
 
static inline const struct rb_callcache *
vm_cc_new(VALUE klass,
          const struct rb_callable_method_entry_struct *cme,
          vm_call_handler call,
          enum vm_cc_type type)
{
    cc_check_class(klass);
    struct rb_callcache *cc = SHAREABLE_IMEMO_NEW(struct rb_callcache, imemo_callcache, klass);
    *((struct rb_callable_method_entry_struct **)&cc->cme_) = (struct rb_callable_method_entry_struct *)cme;
    *((vm_call_handler *)&cc->call_) = call;
 
    switch (type) {
      case cc_type_normal:
        break;
      case cc_type_super:
        *(VALUE *)&cc->flags |= VM_CALLCACHE_SUPER;
        break;
      case cc_type_refinement:
        *(VALUE *)&cc->flags |= VM_CALLCACHE_REFINEMENT;
        rb_vm_insert_cc_refinement(cc);
        break;
    }
 
    if (cme) {
        if (cme->def->type == VM_METHOD_TYPE_ATTRSET || cme->def->type == VM_METHOD_TYPE_IVAR) {
            vm_cc_attr_index_initialize(cc, INVALID_SHAPE_ID);
        }
    }
    else {
        *(VALUE *)&cc->flags |= VM_CALLCACHE_INVALID_SUPER;
    }
 
    RB_DEBUG_COUNTER_INC(cc_new);
    return cc;
}
 
static inline bool
vm_cc_super_p(const struct rb_callcache *cc)
{
    return (cc->flags & VM_CALLCACHE_SUPER) != 0;
}
 
static inline bool
vm_cc_refinement_p(const struct rb_callcache *cc)
{
    return (cc->flags & VM_CALLCACHE_REFINEMENT) != 0;
}
 
#define VM_CC_ON_STACK(clazz, call, aux, cme) \
    (struct rb_callcache) {                   \
        .flags = T_IMEMO |                    \
            (imemo_callcache << FL_USHIFT) |  \
            VM_CALLCACHE_UNMARKABLE |         \
            VM_CALLCACHE_ON_STACK,            \
        .klass = cc_check_class(clazz),       \
        .cme_  = cme,                         \
        .call_ = call,                        \
        .aux_  = aux,                         \
    }
 
static inline bool
vm_cc_class_check(const struct rb_callcache *cc, VALUE klass)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc_check_class(cc->klass));
    return cc->klass == klass;
}
 
static inline int
vm_cc_markable(const struct rb_callcache *cc)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    return FL_TEST_RAW((VALUE)cc, VM_CALLCACHE_UNMARKABLE) == 0;
}
 
static inline bool
vm_cc_invalid_super(const struct rb_callcache *cc)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    // Set when calling super and there is no superclass.
    return FL_TEST_RAW((VALUE)cc, VM_CALLCACHE_INVALID_SUPER);
}
 
static inline bool
vm_cc_valid(const struct rb_callcache *cc)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc_check_class(cc->klass));
 
    return !UNDEF_P(cc->klass);
}
 
static inline const struct rb_callable_method_entry_struct *
vm_cc_cme(const struct rb_callcache *cc)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc->klass != Qundef || !vm_cc_markable(cc) || vm_cc_invalid_super(cc));
    VM_ASSERT(cc_check_class(cc->klass));
    VM_ASSERT(cc->call_ == NULL   || // not initialized yet
              !vm_cc_markable(cc) ||
              vm_cc_invalid_super(cc) ||
              cc->cme_ != NULL);
 
    return cc->cme_;
}
 
static inline vm_call_handler
vm_cc_call(const struct rb_callcache *cc)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc->call_ != NULL);
    VM_ASSERT(cc->klass != Qundef || !vm_cc_markable(cc) || vm_cc_invalid_super(cc));
    VM_ASSERT(cc_check_class(cc->klass));
    return cc->call_;
}
 
static inline void
vm_unpack_shape_and_index(const uint64_t cache_value, shape_id_t *shape_id, attr_index_t *index)
{
    union rb_attr_index_cache cache = {
        .pack = cache_value,
    };
    *shape_id = cache.unpack.shape_id;
    *index = cache.unpack.index - 1;
}
 
static inline void
vm_cc_atomic_shape_and_index(const struct rb_callcache *cc, shape_id_t *shape_id, attr_index_t *index)
{
    vm_unpack_shape_and_index(ATOMIC_U64_LOAD_RELAXED(cc->aux_.attr.value), shape_id, index);
}
 
static inline void
vm_ic_atomic_shape_and_index(const struct iseq_inline_iv_cache_entry *ic, shape_id_t *shape_id, attr_index_t *index)
{
    vm_unpack_shape_and_index(ATOMIC_U64_LOAD_RELAXED(ic->value), shape_id, index);
}
 
static inline unsigned int
vm_cc_cmethod_missing_reason(const struct rb_callcache *cc)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    return cc->aux_.method_missing_reason;
}
 
static inline bool
vm_cc_invalidated_p(const struct rb_callcache *cc)
{
    if (vm_cc_valid(cc) && !METHOD_ENTRY_INVALIDATED(vm_cc_cme(cc))) {
        return false;
    }
    else {
        return true;
    }
}
 
/* callcache: mutate */
 
static inline void
vm_cc_call_set(const struct rb_callcache *cc, vm_call_handler call)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc != vm_cc_empty());
    *(vm_call_handler *)&cc->call_ = call;
}
 
static inline void
set_vm_cc_ivar(const struct rb_callcache *cc)
{
    *(VALUE *)&cc->flags |= VM_CALLCACHE_IVAR;
}
 
static inline uint64_t
vm_pack_shape_and_index(shape_id_t shape_id, attr_index_t index)
{
    union rb_attr_index_cache cache = {
        .unpack = {
            .shape_id = shape_id,
            .index = index + 1,
        }
    };
    return cache.pack;
}
 
static inline void
vm_cc_attr_index_set(const struct rb_callcache *cc, attr_index_t index, shape_id_t dest_shape_id)
{
    uint64_t *attr_value = (uint64_t *)&cc->aux_.attr.value;
    if (!vm_cc_markable(cc)) {
        *attr_value = vm_pack_shape_and_index(INVALID_SHAPE_ID, ATTR_INDEX_NOT_SET);
        return;
    }
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc != vm_cc_empty());
    *attr_value = vm_pack_shape_and_index(dest_shape_id, index);
    set_vm_cc_ivar(cc);
}
 
static inline bool
vm_cc_ivar_p(const struct rb_callcache *cc)
{
    return (cc->flags & VM_CALLCACHE_IVAR) != 0;
}
 
static inline void
vm_ic_attr_index_set(const rb_iseq_t *iseq, struct iseq_inline_iv_cache_entry *ic, attr_index_t index, shape_id_t dest_shape_id)
{
    ATOMIC_U64_SET_RELAXED(ic->value, vm_pack_shape_and_index(dest_shape_id, index));
}
 
static inline void
vm_ic_attr_index_initialize(struct iseq_inline_iv_cache_entry *ic, shape_id_t shape_id)
{
    ATOMIC_U64_SET_RELAXED(ic->value, vm_pack_shape_and_index(shape_id, ATTR_INDEX_NOT_SET));
}
 
static inline void
vm_cc_method_missing_reason_set(const struct rb_callcache *cc, enum method_missing_reason reason)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc != vm_cc_empty());
    *(enum method_missing_reason *)&cc->aux_.method_missing_reason = reason;
}
 
static inline void
vm_cc_bf_set(const struct rb_callcache *cc, const struct rb_builtin_function *bf)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc != vm_cc_empty());
    *(const struct rb_builtin_function **)&cc->aux_.bf = bf;
    *(VALUE *)&cc->flags |= VM_CALLCACHE_BF;
}
 
static inline bool
vm_cc_bf_p(const struct rb_callcache *cc)
{
    return (cc->flags & VM_CALLCACHE_BF) != 0;
}
 
static inline void
vm_cc_invalidate(const struct rb_callcache *cc)
{
    VM_ASSERT(IMEMO_TYPE_P(cc, imemo_callcache));
    VM_ASSERT(cc != vm_cc_empty());
    // TODO: rb_multi_ractor_p() is a workaround to stabilize CI
    VM_ASSERT(cc->klass != Qundef || rb_multi_ractor_p()); // should be enable
 
    *(VALUE *)&cc->klass = Qundef;
    RB_DEBUG_COUNTER_INC(cc_ent_invalidate);
}
 
/* calldata */
 
struct rb_call_data {
    const struct rb_callinfo *ci;
    const struct rb_callcache *cc;
};
 
struct rb_class_cc_entries {
#if VM_CHECK_MODE > 0
    VALUE debug_sig;
#endif
    int capa;
    int len;
    const struct rb_callable_method_entry_struct *cme;
    struct rb_class_cc_entries_entry {
        const struct rb_callcache *cc;
        unsigned int argc;
        unsigned short flag;
        unsigned short kw_len;
    } entries[FLEX_ARY_LEN];
};
 
/* entries[].flag is an unsigned short, so every VM_CALL flag bit must fit in 16 bits. */
STATIC_ASSERT(cc_entries_flag_fits_in_short, VM_CALL__END <= 16);
 
/* entries[].kw_len is an unsigned short, so a call site cannot carry, nor a method
   declare, more keyword arguments than this.  Enforced at compile time. */
#define VM_CALL_KW_LEN_MAX UINT16_MAX
 
static inline size_t
vm_ccs_alloc_size(size_t capa)
{
    return offsetof(struct rb_class_cc_entries, entries) + (sizeof(struct rb_class_cc_entries_entry) * capa);
}
 
#if VM_CHECK_MODE > 0
 
const rb_callable_method_entry_t *rb_vm_lookup_overloaded_cme(const rb_callable_method_entry_t *cme);
void rb_vm_dump_overloaded_cme_table(void);
 
static inline bool
vm_ccs_p(const struct rb_class_cc_entries *ccs)
{
    return ccs->debug_sig == ~(VALUE)ccs;
}
 
static inline bool
vm_cc_check_cme(const struct rb_callcache *cc, const rb_callable_method_entry_t *cme)
{
    bool valid;
    RB_VM_LOCKING_NO_BARRIER() {
        valid = vm_cc_cme(cc) == cme ||
            (cme->def->iseq_overload && vm_cc_cme(cc) == rb_vm_lookup_overloaded_cme(cme));
    }
    if (valid) {
        return true;
    }
#if 1
        // debug print
 
        fprintf(stderr, "iseq_overload:%d, cme:%p (def:%p), cm_cc_cme(cc):%p (def:%p)\n",
                (int)cme->def->iseq_overload,
                cme, cme->def,
                vm_cc_cme(cc), vm_cc_cme(cc)->def);
        rp(cme);
        rp(vm_cc_cme(cc));
        rp(rb_vm_lookup_overloaded_cme(cme));
#endif
    return false;
}
 
#endif
 
#endif /* RUBY_VM_CALLINFO_H */