< :前の番号
^ :番号順リスト
> :次の番号
P :前の記事（スレッド移動）
N :次の記事（スレッド移動）
|<:前のスレッド
>|:次のスレッド
^ :返事先
_:自分への返事
>:同じ返事先を持つ記事（前）
<:同じ返事先を持つ記事（後）
---:分割してスレッド表示、再表示
| :分割して（縦）スレッド表示、再表示
~ :スレッドのフレーム消去
.:インデックス
..:インデックスのインデックス
Issue #16161 has been updated by wanabe (_ wanabe).
How about adding `vm_call_iseq_setup_tailcall_opt_start` as same as `vm_call_iseq_setup_normal_opt_start`?
(Copy-and-paste code, sorry!)
```patch
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index a83e3a952a..4abee2fadd 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -1825,6 +1825,30 @@ vm_call_iseq_setup_normal_opt_start(rb_execution_context_t *ec, rb_control_frame
return vm_call_iseq_setup_normal(ec, cfp, calling, cc->me, opt_pc, param - delta, local);
}
+static VALUE
+vm_call_iseq_setup_tailcall_opt_start(rb_execution_context_t *ec, rb_control_frame_t *cfp,
+ struct rb_calling_info *calling,
+ const struct rb_call_info *ci, struct rb_call_cache *cc)
+{
+ const rb_iseq_t *iseq = def_iseq_ptr(cc->me->def);
+ const int lead_num = iseq->body->param.lead_num;
+ const int opt = calling->argc - lead_num;
+ const int opt_pc = (int)iseq->body->param.opt_table[opt];
+
+ RB_DEBUG_COUNTER_INC(ccf_iseq_opt);
+
+#if USE_OPT_HIST
+ if (opt_pc < OPT_HIST_MAX) {
+ opt_hist[opt]++;
+ }
+ else {
+ opt_hist[OPT_HIST_MAX]++;
+ }
+#endif
+
+ return vm_call_iseq_setup_tailcall(ec, cfp, calling, ci, cc, opt_pc);
+}
+
static void
args_setup_kw_parameters(rb_execution_context_t *const ec, const rb_iseq_t *const iseq,
VALUE *const passed_values, const int passed_keyword_len, const VALUE *const passed_keywords,
@@ -1909,9 +1933,16 @@ vm_callee_setup_arg(rb_execution_context_t *ec, struct rb_calling_info *calling,
argument_arity_error(ec, iseq, argc, lead_num, lead_num + opt_num);
}
- CC_SET_FASTPATH(cc, vm_call_iseq_setup_normal_opt_start,
- !IS_ARGS_SPLAT(ci) && !IS_ARGS_KEYWORD(ci) &&
- !(METHOD_ENTRY_VISI(cc->me) == METHOD_VISI_PROTECTED));
+ if (LIKELY(!(ci->flag & VM_CALL_TAILCALL))) {
+ CC_SET_FASTPATH(cc, vm_call_iseq_setup_normal_opt_start,
+ !IS_ARGS_SPLAT(ci) && !IS_ARGS_KEYWORD(ci) &&
+ !(METHOD_ENTRY_VISI(cc->me) == METHOD_VISI_PROTECTED));
+ }
+ else {
+ CC_SET_FASTPATH(cc, vm_call_iseq_setup_tailcall_opt_start,
+ !IS_ARGS_SPLAT(ci) && !IS_ARGS_KEYWORD(ci) &&
+ !(METHOD_ENTRY_VISI(cc->me) == METHOD_VISI_PROTECTED));
+ }
/* initialize opt vars for self-references */
VM_ASSERT((int)iseq->body->param.size == lead_num + opt_num);
```
----------------------------------------
Bug #16161: tailcall_optimization may be disabled after r67315
https://bugs.ruby-lang.org/issues/16161#change-81535
* Author: wanabe (_ wanabe)
* Status: Open
* Priority: Normal
* Assignee:
* Target version:
* ruby -v: ruby 2.7.0dev (2019-09-09T23:18:03Z master 3678c37119) [x86_64-linux]
* Backport: 2.5: UNKNOWN, 2.6: UNKNOWN
----------------------------------------
Before r67315:
```
$ ./miniruby -v -e 'iseq = RubyVM::InstructionSequence.compile("def foo(n, s = 0);return s if n < 1;foo(n - 1, n + s); end", tailcall_optimization: true); iseq.eval; p foo(900_000)'
ruby 2.7.0dev (2019-03-20 trunk 67314) [x86_64-linux]
405000450000
```
After r67315:
```
$ ./miniruby -v -e 'iseq = RubyVM::InstructionSequence.compile("def foo(n, s = 0);return s if n < 1;foo(n - 1, n + s); end", tailcall_optimization: true); iseq.eval; p foo(900_000)'
ruby 2.7.0dev (2019-03-20 trunk 67315) [x86_64-linux]
Traceback (most recent call last):
10080: from -e:1:in `<main>'
10079: from <compiled>:1:in `foo'
10078: from <compiled>:1:in `foo'
10077: from <compiled>:1:in `foo'
10076: from <compiled>:1:in `foo'
10075: from <compiled>:1:in `foo'
10074: from <compiled>:1:in `foo'
10073: from <compiled>:1:in `foo'
... 10068 levels...
4: from <compiled>:1:in `foo'
3: from <compiled>:1:in `foo'
2: from <compiled>:1:in `foo'
1: from <compiled>:1:in `foo'
<compiled>:1:in `foo': stack level too deep (SystemStackError)
```
master:
```
$ ./miniruby -v -e 'iseq = RubyVM::InstructionSequence.compile("def foo(n, s = 0);return s if n < 1;foo(n - 1, n + s); end", tailcall_optimization: true); iseq.eval; p foo(900_000)'
ruby 2.7.0dev (2019-09-09T23:18:03Z master 3678c37119) [x86_64-linux]
Traceback (most recent call last):
10080: from -e:1:in `<main>'
10079: from <compiled>:1:in `foo'
10078: from <compiled>:1:in `foo'
10077: from <compiled>:1:in `foo'
10076: from <compiled>:1:in `foo'
10075: from <compiled>:1:in `foo'
10074: from <compiled>:1:in `foo'
10073: from <compiled>:1:in `foo'
... 10068 levels...
4: from <compiled>:1:in `foo'
3: from <compiled>:1:in `foo'
2: from <compiled>:1:in `foo'
1: from <compiled>:1:in `foo'
<compiled>:1:in `foo': stack level too deep (SystemStackError)
```
I think ruby should not raise SystemStackError with tailcall_optimization, should it?
--
https://bugs.ruby-lang.org/
Unsubscribe: <mailto:ruby-core-request / ruby-lang.org?subject=unsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>