From 256c5f257743401d4ee7e2ba756ef2ffd22e4d7a Mon Sep 17 00:00:00 2001 From: ko1 Date: Mon, 17 Dec 2012 22:04:12 +0000 Subject: * method.h: remove `VM_METHOD_TYPE_CFUNC_FRAMELESS' method type. This method type is for optimized CFUNC such as Fixnum#+ and so on. This feature is half-baked and no way to use them. [Background] Now, VM has opt_plus instructions to optimize `+' methods for some Classes (such as Fixnum, Float (flonum)). We call this type of instructions as `specialized instructions'. This simple technique improve simple program dramatically. However, we can make specialized instructions for only several types (classes) and selectors (method names) because a large instruction will be slow. In other words, this technique has no extensibility. To overcome this problem, VM_METHOD_TYPE_CFUNC_FRAMELESS was introduced (r37198). This type is a variant of CFUNC, but called their functiions directly without building a method frame. Any CFUNC method can be defined as frameless methods if a method is not needed to make method frame. Frameless methods are faster as specialized instructions (a bit slower, but no need to care). No problem described at http://charlie.bz/blog/why-do-singleton-methods-make-ruby-slow because this technique doesn't see class, but see method body itself. Alias is also no problem. [Problem] However, we can't set frameless method type for polymorphic methods such as Array#[]. Necessity for method frame depends on which parameter type. For example, Fixnum#+ needs method frame if coerce is needed. Current VM_METHOD_TYPE_CFUNC_FRAMELESS is not flexible and need more tuning to introduce it. Expected behavior of frameless method type may be: result = optimized_cfunc(params); /* call optimized cfunc */ if (result == Qundef) { result = normal_cfunc(); } This is why I say this feature is half-baked. We need to learn primitive method in Smalltalk more. (I heard this name at RubyConf Taiwan this month. Thanks!) [Conclusion] Nobody may use this feature and there is no compatibility issue. This feature goes to next minor (2.1?). * proc.c (rb_method_entry_arity): ditto. * vm_eval.c, vm_insnhelper.c, vm_method.c: ditto. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@38431 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- vm_eval.c | 6 ------ 1 file changed, 6 deletions(-) (limited to 'vm_eval.c') diff --git a/vm_eval.c b/vm_eval.c index 190d2bc559..628c76a1b1 100644 --- a/vm_eval.c +++ b/vm_eval.c @@ -219,12 +219,6 @@ vm_call0_body(rb_thread_t* th, rb_call_info_t *ci, const VALUE *argv) rb_bug("vm_call0: unsupported optimized method type (%d)", ci->me->def->body.optimize_type); } break; - case VM_METHOD_TYPE_CFUNC_FRAMELESS: - { - /* TODO: can optimize it */ - const rb_method_cfunc_t *cfunc = &ci->me->def->body.cfunc; - return cfunc->invoker(cfunc->func, ci->recv, ci->argc, argv); - } case VM_METHOD_TYPE_UNDEF: break; } -- cgit v1.2.3