Пример #1
0
Файл: array.c Проект: iij/mruby
static mrb_value
mrb_ary_aget(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);
  mrb_int i, len, alen;
  mrb_value index;

  if (mrb_get_args(mrb, "o|i", &index, &len) == 1) {
    switch (mrb_type(index)) {
      /* a[n..m] */
    case MRB_TT_RANGE:
      if (mrb_range_beg_len(mrb, index, &i, &len, ARY_LEN(a), TRUE) == 1) {
        return ary_subseq(mrb, a, i, len);
      }
      else {
        return mrb_nil_value();
      }
    case MRB_TT_FIXNUM:
      return mrb_ary_ref(mrb, self, mrb_fixnum(index));
    default:
      return mrb_ary_ref(mrb, self, aget_index(mrb, index));
    }
  }

  i = aget_index(mrb, index);
  alen = ARY_LEN(a);
  if (i < 0) i += alen;
  if (i < 0 || alen < i) return mrb_nil_value();
  if (len < 0) return mrb_nil_value();
  if (alen == i) return mrb_ary_new(mrb);
  if (len > alen - i) len = alen - i;

  return ary_subseq(mrb, a, i, len);
}
Пример #2
0
Файл: gc.c Проект: chasonr/mruby
/* mrb_gc_unregister() removes the object from GC root. */
MRB_API void
mrb_gc_unregister(mrb_state *mrb, mrb_value obj)
{
  mrb_sym root = mrb_intern_lit(mrb, GC_ROOT_NAME);
  mrb_value table = mrb_gv_get(mrb, root);
  struct RArray *a;
  mrb_int i;

  if (mrb_nil_p(table)) return;
  if (mrb_type(table) != MRB_TT_ARRAY) {
    mrb_gv_set(mrb, root, mrb_nil_value());
    return;
  }
  a = mrb_ary_ptr(table);
  mrb_ary_modify(mrb, a);
  for (i = 0; i < ARY_LEN(a); i++) {
    if (mrb_obj_eq(mrb, ARY_PTR(a)[i], obj)) {
      mrb_int len = ARY_LEN(a)-1;
      mrb_value *ptr = ARY_PTR(a);

      ARY_SET_LEN(a, len);
      memmove(&ptr[i], &ptr[i + 1], (len - i) * sizeof(mrb_value));
      break;
    }
  }
}
Пример #3
0
static mrb_value
mrb_ary_times(mrb_state *mrb, mrb_value self)
{
  struct RArray *a1 = mrb_ary_ptr(self);
  struct RArray *a2;
  mrb_value *ptr;
  mrb_int times, len1;

  mrb_get_args(mrb, "i", &times);
  if (times < 0) {
    mrb_raise(mrb, E_ARGUMENT_ERROR, "negative argument");
  }
  if (times == 0) return mrb_ary_new(mrb);
  if (ARY_MAX_SIZE / times < ARY_LEN(a1)) {
    mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");
  }
  len1 = ARY_LEN(a1);
  a2 = ary_new_capa(mrb, len1 * times);
  ARY_SET_LEN(a2, len1 * times);
  ptr = ARY_PTR(a2);
  while (times--) {
    array_copy(ptr, ARY_PTR(a1), len1);
    ptr += len1;
  }

  return mrb_obj_value(a2);
}
Пример #4
0
static mrb_value
mrb_ary_delete_at(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);
  mrb_int   index;
  mrb_value val;
  mrb_value *ptr;
  mrb_int len, alen = ARY_LEN(a);

  mrb_get_args(mrb, "i", &index);
  if (index < 0) index += alen;
  if (index < 0 || alen <= index) return mrb_nil_value();

  ary_modify(mrb, a);
  ptr = ARY_PTR(a);
  val = ptr[index];

  ptr += index;
  len = alen - index;
  while (--len) {
    *ptr = *(ptr+1);
    ++ptr;
  }
  ARY_SET_LEN(a, alen-1);

  ary_shrink_capa(mrb, a);

  return val;
}
Пример #5
0
static mrb_value
mrb_ary_unshift_m(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);
  mrb_value *vals, *ptr;
  mrb_int alen, len;

  mrb_get_args(mrb, "*!", &vals, &alen);
  len = ARY_LEN(a);
  if (alen > ARY_MAX_SIZE - len) {
    mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");
  }
  if (ARY_SHARED_P(a)
      && a->as.heap.aux.shared->refcnt == 1 /* shared only referenced from this array */
      && a->as.heap.ptr - a->as.heap.aux.shared->ptr >= alen) /* there's room for unshifted item */ {
    ary_modify_check(mrb, a);
    a->as.heap.ptr -= len;
    ptr = a->as.heap.ptr;
  }
  else {
    ary_modify(mrb, a);
    if (alen == 0) return self;
    if (ARY_CAPA(a) < len + alen)
      ary_expand_capa(mrb, a, len + alen);
    ptr = ARY_PTR(a);
    value_move(ptr + alen, ptr, len);
  }
  array_copy(ptr, vals, alen);
  ARY_SET_LEN(a, len+alen);
  while (alen--) {
    mrb_field_write_barrier_value(mrb, (struct RBasic*)a, vals[alen]);
  }

  return self;
}
Пример #6
0
MRB_API mrb_value
mrb_ary_shift(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);
  mrb_int len = ARY_LEN(a);
  mrb_value val;

  ary_modify_check(mrb, a);
  if (len == 0) return mrb_nil_value();
  if (ARY_SHARED_P(a)) {
  L_SHIFT:
    val = a->as.heap.ptr[0];
    a->as.heap.ptr++;
    a->as.heap.len--;
    return val;
  }
  if (len > ARY_SHIFT_SHARED_MIN) {
    ary_make_shared(mrb, a);
    goto L_SHIFT;
  }
  else {
    mrb_value *ptr = ARY_PTR(a);
    mrb_int size = len;

    val = *ptr;
    while (--size) {
      *ptr = *(ptr+1);
      ++ptr;
    }
    ARY_SET_LEN(a, len-1);
  }
  return val;
}
Пример #7
0
/* self = [1,2,3]
   item = 0
   self.unshift item
   p self #=> [0, 1, 2, 3] */
MRB_API mrb_value
mrb_ary_unshift(mrb_state *mrb, mrb_value self, mrb_value item)
{
  struct RArray *a = mrb_ary_ptr(self);
  mrb_int len = ARY_LEN(a);

  if (ARY_SHARED_P(a)
      && a->as.heap.aux.shared->refcnt == 1 /* shared only referenced from this array */
      && a->as.heap.ptr - a->as.heap.aux.shared->ptr >= 1) /* there's room for unshifted item */ {
    a->as.heap.ptr--;
    a->as.heap.ptr[0] = item;
  }
  else {
    mrb_value *ptr;

    ary_modify(mrb, a);
    if (ARY_CAPA(a) < len + 1)
      ary_expand_capa(mrb, a, len + 1);
    ptr = ARY_PTR(a);
    value_move(ptr + 1, ptr, len);
    ptr[0] = item;
  }
  ARY_SET_LEN(a, len+1);
  mrb_field_write_barrier_value(mrb, (struct RBasic*)a, item);

  return self;
}
Пример #8
0
static mrb_value
mrb_ary_empty_p(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);

  return mrb_bool_value(ARY_LEN(a) == 0);
}
Пример #9
0
static mrb_value
mrb_ary_size(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);

  return mrb_fixnum_value(ARY_LEN(a));
}
Пример #10
0
static struct RArray*
ary_dup(mrb_state *mrb, struct RArray *a)
{
  mrb_int len = ARY_LEN(a);
  struct RArray *d = ary_new_capa(mrb, len);

  ary_replace(mrb, d, ARY_PTR(a), len);
  return d;
}
Пример #11
0
static mrb_value
mrb_ary_reverse(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self), *b = ary_new_capa(mrb, ARY_LEN(a));
  mrb_int len = ARY_LEN(a);

  if (len > 0) {
    mrb_value *p1, *p2, *e;

    p1 = ARY_PTR(a);
    e  = p1 + len;
    p2 = ARY_PTR(b) + len - 1;
    while (p1 < e) {
      *p2-- = *p1++;
    }
    ARY_SET_LEN(b, len);
  }
  return mrb_obj_value(b);
}
Пример #12
0
MRB_API void
mrb_ary_replace(mrb_state *mrb, mrb_value self, mrb_value other)
{
  struct RArray *a1 = mrb_ary_ptr(self);
  struct RArray *a2 = mrb_ary_ptr(other);

  if (a1 != a2) {
    ary_replace(mrb, a1, ARY_PTR(a2), ARY_LEN(a2));
  }
}
Пример #13
0
MRB_API mrb_value
mrb_ary_pop(mrb_state *mrb, mrb_value ary)
{
  struct RArray *a = mrb_ary_ptr(ary);
  mrb_int len = ARY_LEN(a);

  ary_modify_check(mrb, a);
  if (len == 0) return mrb_nil_value();
  ARY_SET_LEN(a, len-1);
  return ARY_PTR(a)[len-1];
}
Пример #14
0
static mrb_value
mrb_ary_plus(mrb_state *mrb, mrb_value self)
{
  struct RArray *a1 = mrb_ary_ptr(self);
  struct RArray *a2;
  mrb_value *ptr;
  mrb_int blen, len1;

  mrb_get_args(mrb, "a", &ptr, &blen);
  if (ARY_MAX_SIZE - blen < ARY_LEN(a1)) {
    mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");
  }
  len1 = ARY_LEN(a1);
  a2 = ary_new_capa(mrb, len1 + blen);
  array_copy(ARY_PTR(a2), ARY_PTR(a1), len1);
  array_copy(ARY_PTR(a2) + len1, ptr, blen);
  ARY_SET_LEN(a2, len1+blen);

  return mrb_obj_value(a2);
}
Пример #15
0
MRB_API mrb_value
mrb_ary_ref(mrb_state *mrb, mrb_value ary, mrb_int n)
{
  struct RArray *a = mrb_ary_ptr(ary);
  mrb_int len = ARY_LEN(a);

  /* range check */
  if (n < 0) n += len;
  if (n < 0 || len <= n) return mrb_nil_value();

  return ARY_PTR(a)[n];
}
Пример #16
0
Файл: array.c Проект: iij/mruby
static mrb_value
mrb_ary_first(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);
  mrb_int size, alen;

  if (mrb_get_argc(mrb) == 0) {
    return (ARY_LEN(a) > 0)? ARY_PTR(a)[0]: mrb_nil_value();
  }
  mrb_get_args(mrb, "|i", &size);
  if (size < 0) {
    mrb_raise(mrb, E_ARGUMENT_ERROR, "negative array size");
  }

  alen = ARY_LEN(a);
  if (size > alen) size = alen;
  if (ARY_SHARED_P(a)) {
    return ary_subseq(mrb, a, 0, size);
  }
  return mrb_ary_new_from_values(mrb, size, ARY_PTR(a));
}
Пример #17
0
MRB_API void
mrb_ary_push(mrb_state *mrb, mrb_value ary, mrb_value elem)
{
  struct RArray *a = mrb_ary_ptr(ary);
  mrb_int len = ARY_LEN(a);

  ary_modify(mrb, a);
  if (len == ARY_CAPA(a))
    ary_expand_capa(mrb, a, len + 1);
  ARY_PTR(a)[len] = elem;
  ARY_SET_LEN(a, len+1);
  mrb_field_write_barrier_value(mrb, (struct RBasic*)a, elem);
}
Пример #18
0
static mrb_value
mrb_ary_last(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);
  mrb_int size, alen = ARY_LEN(a);

  if (mrb_get_args(mrb, "|i", &size) == 0)
    return (alen > 0)? ARY_PTR(a)[alen - 1]: mrb_nil_value();

  if (size < 0) {
    mrb_raise(mrb, E_ARGUMENT_ERROR, "negative array size");
  }
  if (size > alen) size = alen;
  if (ARY_SHARED_P(a) || size > ARY_DEFAULT_LEN) {
    return ary_subseq(mrb, a, alen - size, size);
  }
  return mrb_ary_new_from_values(mrb, size, ARY_PTR(a) + alen - size);
}
Пример #19
0
Файл: array.c Проект: iij/mruby
static mrb_value
mrb_ary_push_m(mrb_state *mrb, mrb_value self)
{
  mrb_value *argv;
  mrb_int len, len2, alen;
  struct RArray *a;

  mrb_get_args(mrb, "*!", &argv, &alen);
  a = mrb_ary_ptr(self);
  ary_modify(mrb, a);
  len = ARY_LEN(a);
  len2 = len + alen;
  if (ARY_CAPA(a) < len2) {
    ary_expand_capa(mrb, a, len2);
  }
  array_copy(ARY_PTR(a)+len, argv, alen);
  ARY_SET_LEN(a, len2);
  mrb_write_barrier(mrb, (struct RBasic*)a);

  return self;
}
Пример #20
0
static mrb_value
mrb_ary_reverse_bang(mrb_state *mrb, mrb_value self)
{
  struct RArray *a = mrb_ary_ptr(self);
  mrb_int len = ARY_LEN(a);

  if (len > 1) {
    mrb_value *p1, *p2;

    ary_modify(mrb, a);
    p1 = ARY_PTR(a);
    p2 = p1 + len - 1;

    while (p1 < p2) {
      mrb_value tmp = *p1;
      *p1++ = *p2;
      *p2-- = tmp;
    }
  }
  return self;
}
Пример #21
0
Файл: array.c Проект: iij/mruby
static void
ary_replace(mrb_state *mrb, struct RArray *a, struct RArray *b)
{
  mrb_int len = ARY_LEN(b);

  ary_modify_check(mrb, a);
  if (a == b) return;
  if (ARY_SHARED_P(a)) {
    mrb_ary_decref(mrb, a->as.heap.aux.shared);
    a->as.heap.aux.capa = 0;
    a->as.heap.len = 0;
    a->as.heap.ptr = NULL;
    ARY_UNSET_SHARED_FLAG(a);
  }
  if (ARY_SHARED_P(b)) {
  shared_b:
    if (ARY_EMBED_P(a)) {
      ARY_UNSET_EMBED_FLAG(a);
    }
    else {
      mrb_free(mrb, a->as.heap.ptr);
    }
    a->as.heap.ptr = b->as.heap.ptr;
    a->as.heap.len = len;
    a->as.heap.aux.shared = b->as.heap.aux.shared;
    a->as.heap.aux.shared->refcnt++;
    ARY_SET_SHARED_FLAG(a);
    mrb_write_barrier(mrb, (struct RBasic*)a);
    return;
  }
  if (!MRB_FROZEN_P(b) && len > ARY_REPLACE_SHARED_MIN) {
    ary_make_shared(mrb, b);
    goto shared_b;
  }
  if (ARY_CAPA(a) < len)
    ary_expand_capa(mrb, a, len);
  array_copy(ARY_PTR(a), ARY_PTR(b), len);
  mrb_write_barrier(mrb, (struct RBasic*)a);
  ARY_SET_LEN(a, len);
}
Пример #22
0
static void
ary_concat(mrb_state *mrb, struct RArray *a, struct RArray *a2)
{
  mrb_int len;

  if (ARY_LEN(a2) > ARY_MAX_SIZE - ARY_LEN(a)) {
    mrb_raise(mrb, E_ARGUMENT_ERROR, "array size too big");
  }
  len = ARY_LEN(a) + ARY_LEN(a2);

  ary_modify(mrb, a);
  if (ARY_CAPA(a) < len) {
    ary_expand_capa(mrb, a, len);
  }
  array_copy(ARY_PTR(a)+ARY_LEN(a), ARY_PTR(a2), ARY_LEN(a2));
  mrb_write_barrier(mrb, (struct RBasic*)a);
  ARY_SET_LEN(a, len);
}
Пример #23
0
MRB_API void
mrb_ary_set(mrb_state *mrb, mrb_value ary, mrb_int n, mrb_value val)
{
  struct RArray *a = mrb_ary_ptr(ary);
  mrb_int len = ARY_LEN(a);

  ary_modify(mrb, a);
  /* range check */
  if (n < 0) {
    n += len;
    if (n < 0) {
      mrb_raisef(mrb, E_INDEX_ERROR, "index %S out of array", mrb_fixnum_value(n - len));
    }
  }
  if (len <= n) {
    if (ARY_CAPA(a) <= n)
      ary_expand_capa(mrb, a, n + 1);
    ary_fill_with_nil(ARY_PTR(a) + len, n + 1 - len);
    ARY_SET_LEN(a, n+1);
  }

  ARY_PTR(a)[n] = val;
  mrb_field_write_barrier_value(mrb, (struct RBasic*)a, val);
}
Пример #24
0
Файл: gc.c Проект: chasonr/mruby
static size_t
gc_gray_mark(mrb_state *mrb, mrb_gc *gc, struct RBasic *obj)
{
  size_t children = 0;

  gc_mark_children(mrb, gc, obj);

  switch (obj->tt) {
  case MRB_TT_ICLASS:
    children++;
    break;

  case MRB_TT_CLASS:
  case MRB_TT_SCLASS:
  case MRB_TT_MODULE:
    {
      struct RClass *c = (struct RClass*)obj;

      children += mrb_gc_mark_iv_size(mrb, (struct RObject*)obj);
      children += mrb_gc_mark_mt_size(mrb, c);
      children++;
    }
    break;

  case MRB_TT_OBJECT:
  case MRB_TT_DATA:
  case MRB_TT_EXCEPTION:
    children += mrb_gc_mark_iv_size(mrb, (struct RObject*)obj);
    break;

  case MRB_TT_ENV:
    children += MRB_ENV_STACK_LEN(obj);
    break;

  case MRB_TT_FIBER:
    {
      struct mrb_context *c = ((struct RFiber*)obj)->cxt;
      size_t i;
      mrb_callinfo *ci;

      if (!c) break;
      /* mark stack */
      i = c->stack - c->stbase;
      if (c->ci) i += c->ci->nregs;
      if (c->stbase + i > c->stend) i = c->stend - c->stbase;
      children += i;

      /* mark ensure stack */
      children += c->eidx;

      /* mark closure */
      if (c->cibase) {
        for (i=0, ci = c->cibase; ci <= c->ci; i++, ci++)
          ;
      }
      children += i;
    }
    break;

  case MRB_TT_ARRAY:
    {
      struct RArray *a = (struct RArray*)obj;
      children += ARY_LEN(a);
    }
    break;

  case MRB_TT_HASH:
    children += mrb_gc_mark_iv_size(mrb, (struct RObject*)obj);
    children += mrb_gc_mark_hash_size(mrb, (struct RHash*)obj);
    break;

  case MRB_TT_PROC:
  case MRB_TT_RANGE:
    children+=2;
    break;

  default:
    break;
  }
  return children;
}
Пример #25
0
Файл: gc.c Проект: chasonr/mruby
static void
gc_mark_children(mrb_state *mrb, mrb_gc *gc, struct RBasic *obj)
{
  mrb_assert(is_gray(obj));
  paint_black(obj);
  gc->gray_list = obj->gcnext;
  mrb_gc_mark(mrb, (struct RBasic*)obj->c);
  switch (obj->tt) {
  case MRB_TT_ICLASS:
    {
      struct RClass *c = (struct RClass*)obj;
      if (MRB_FLAG_TEST(c, MRB_FLAG_IS_ORIGIN))
        mrb_gc_mark_mt(mrb, c);
      mrb_gc_mark(mrb, (struct RBasic*)((struct RClass*)obj)->super);
    }
    break;

  case MRB_TT_CLASS:
  case MRB_TT_MODULE:
  case MRB_TT_SCLASS:
    {
      struct RClass *c = (struct RClass*)obj;

      mrb_gc_mark_mt(mrb, c);
      mrb_gc_mark(mrb, (struct RBasic*)c->super);
    }
    /* fall through */

  case MRB_TT_OBJECT:
  case MRB_TT_DATA:
  case MRB_TT_EXCEPTION:
    mrb_gc_mark_iv(mrb, (struct RObject*)obj);
    break;

  case MRB_TT_PROC:
    {
      struct RProc *p = (struct RProc*)obj;

      mrb_gc_mark(mrb, (struct RBasic*)p->upper);
      mrb_gc_mark(mrb, (struct RBasic*)p->e.env);
    }
    break;

  case MRB_TT_ENV:
    {
      struct REnv *e = (struct REnv*)obj;
      mrb_int i, len;

      if (MRB_ENV_STACK_SHARED_P(e) && e->cxt && e->cxt->fib) {
        mrb_gc_mark(mrb, (struct RBasic*)e->cxt->fib);
      }
      len = MRB_ENV_STACK_LEN(e);
      for (i=0; i<len; i++) {
        mrb_gc_mark_value(mrb, e->stack[i]);
      }
    }
    break;

  case MRB_TT_FIBER:
    {
      struct mrb_context *c = ((struct RFiber*)obj)->cxt;

      if (c) mark_context(mrb, c);
    }
    break;

  case MRB_TT_ARRAY:
    {
      struct RArray *a = (struct RArray*)obj;
      size_t i, e;

      for (i=0,e=ARY_LEN(a); i<e; i++) {
        mrb_gc_mark_value(mrb, ARY_PTR(a)[i]);
      }
    }
    break;

  case MRB_TT_HASH:
    mrb_gc_mark_iv(mrb, (struct RObject*)obj);
    mrb_gc_mark_hash(mrb, (struct RHash*)obj);
    break;

  case MRB_TT_STRING:
    if (RSTR_FSHARED_P(obj) && !RSTR_NOFREE_P(obj)) {
      struct RString *s = (struct RString*)obj;
      mrb_gc_mark(mrb, (struct RBasic*)s->as.heap.aux.fshared);
    }
    break;

  case MRB_TT_RANGE:
    {
      struct RRange *r = (struct RRange*)obj;

      if (r->edges) {
        mrb_gc_mark_value(mrb, r->edges->beg);
        mrb_gc_mark_value(mrb, r->edges->end);
      }
    }
    break;

  default:
    break;
  }
}
Пример #26
0
Файл: array.c Проект: iij/mruby
static struct RArray*
ary_dup(mrb_state *mrb, struct RArray *a)
{
  return ary_new_from_values(mrb, ARY_LEN(a), ARY_PTR(a));
}
Пример #27
0
MRB_API mrb_value
mrb_ary_splice(mrb_state *mrb, mrb_value ary, mrb_int head, mrb_int len, mrb_value rpl)
{
  struct RArray *a = mrb_ary_ptr(ary);
  mrb_int alen = ARY_LEN(a);
  const mrb_value *argv;
  mrb_int argc;
  mrb_int tail;

  ary_modify(mrb, a);

  /* len check */
  if (len < 0) mrb_raisef(mrb, E_INDEX_ERROR, "negative length (%S)", mrb_fixnum_value(len));

  /* range check */
  if (head < 0) {
    head += alen;
    if (head < 0) {
      mrb_raise(mrb, E_INDEX_ERROR, "index is out of array");
    }
  }
  tail = head + len;
  if (alen < len || alen < tail) {
    len = alen - head;
  }

  /* size check */
  if (mrb_array_p(rpl)) {
    argc = RARRAY_LEN(rpl);
    argv = RARRAY_PTR(rpl);
    if (argv == ARY_PTR(a)) {
      struct RArray *r;

      if (argc > 32767) {
        mrb_raise(mrb, E_ARGUMENT_ERROR, "too big recursive splice");
      }
      r = ary_dup(mrb, a);
      argv = ARY_PTR(r);
    }
  }
  else {
    argc = 1;
    argv = &rpl;
  }
  if (head >= alen) {
    if (head > ARY_MAX_SIZE - argc) {
      mrb_raisef(mrb, E_INDEX_ERROR, "index %S too big", mrb_fixnum_value(head));
    }
    len = head + argc;
    if (len > ARY_CAPA(a)) {
      ary_expand_capa(mrb, a, head + argc);
    }
    ary_fill_with_nil(ARY_PTR(a) + alen, head - alen);
    if (argc > 0) {
      array_copy(ARY_PTR(a) + head, argv, argc);
    }
    ARY_SET_LEN(a, len);
  }
  else {
    mrb_int newlen;

    if (alen - len > ARY_MAX_SIZE - argc) {
      mrb_raisef(mrb, E_INDEX_ERROR, "index %S too big", mrb_fixnum_value(alen + argc - len));
    }
    newlen = alen + argc - len;
    if (newlen > ARY_CAPA(a)) {
      ary_expand_capa(mrb, a, newlen);
    }

    if (len != argc) {
      mrb_value *ptr = ARY_PTR(a);
      tail = head + len;
      value_move(ptr + head + argc, ptr + tail, alen - tail);
      ARY_SET_LEN(a, newlen);
    }
    if (argc > 0) {
      value_move(ARY_PTR(a) + head, argv, argc);
    }
  }
  mrb_write_barrier(mrb, (struct RBasic*)a);
  return ary;
}