diff --git a/ChangeLog b/ChangeLog index d0cab08847..a210d9a3f1 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,47 @@ +Tue Dec 18 06:36:12 2012 Koichi Sasada + + * 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. + Tue Dec 18 04:58:22 2012 Koichi Sasada * vm_trace.c (fill_id_and_klass): TracePoint#defined_class returns diff --git a/method.h b/method.h index 2b9ac338e2..e1612cbb9b 100644 --- a/method.h +++ b/method.h @@ -53,7 +53,6 @@ typedef enum { VM_METHOD_TYPE_NOTIMPLEMENTED, VM_METHOD_TYPE_OPTIMIZED, /* Kernel#send, Proc#call, etc */ VM_METHOD_TYPE_MISSING, /* wrapper for method_missing(id) */ - VM_METHOD_TYPE_CFUNC_FRAMELESS, VM_METHOD_TYPE_REFINED, END_OF_ENUMERATION(VM_METHOD_TYPE) diff --git a/proc.c b/proc.c index caa847edd8..3dcbf60d31 100644 --- a/proc.c +++ b/proc.c @@ -1651,7 +1651,6 @@ rb_method_entry_arity(const rb_method_entry_t *me) const rb_method_definition_t *def = me->def; if (!def) return 0; switch (def->type) { - case VM_METHOD_TYPE_CFUNC_FRAMELESS: case VM_METHOD_TYPE_CFUNC: if (def->body.cfunc.argc < 0) return -1; 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; } diff --git a/vm_insnhelper.c b/vm_insnhelper.c index 802ba75dd6..d979d5698a 100644 --- a/vm_insnhelper.c +++ b/vm_insnhelper.c @@ -1619,21 +1619,6 @@ vm_call_opt_call(rb_thread_t *th, rb_control_frame_t *cfp, rb_call_info_t *ci) return rb_vm_invoke_proc(th, proc, argc, argv, ci->blockptr); } -static VALUE -vm_call_cfunc_frameless_unary(rb_thread_t *th, rb_control_frame_t *cfp, rb_call_info_t *ci) -{ - cfp->sp -= 1; - return (*ci->me->def->body.cfunc.func)(ci->recv); -} - -static VALUE -vm_call_cfunc_frameless_binary(rb_thread_t *th, rb_control_frame_t *cfp, rb_call_info_t *ci) -{ - VALUE obj = *cfp->sp; - cfp->sp -= 2; - return (*ci->me->def->body.cfunc.func)(ci->recv, obj); -} - static VALUE vm_call_method_missing(rb_thread_t *th, rb_control_frame_t *reg_cfp, rb_call_info_t *ci) { @@ -1748,20 +1733,6 @@ vm_call_method(rb_thread_t *th, rb_control_frame_t *cfp, rb_call_info_t *ci) } break; } - case VM_METHOD_TYPE_CFUNC_FRAMELESS: - switch (ci->me->def->body.cfunc.argc) { - case 0: - rb_check_arity(ci->argc, 0, 0); - CI_SET_FASTPATH(ci, vm_call_cfunc_frameless_unary, enable_fastpath && !(ci->flag & VM_CALL_ARGS_SPLAT)); - return vm_call_cfunc_frameless_unary(th, cfp, ci); - case 1: - rb_check_arity(ci->argc, 0, 1); - CI_SET_FASTPATH(ci, vm_call_cfunc_frameless_binary, enable_fastpath && !(ci->flag & VM_CALL_ARGS_SPLAT)); - return vm_call_cfunc_frameless_binary(th, cfp, ci); - default: - rb_bug("vm_call_method: unsupported cfunc_fast argc (%d)", ci->me->def->body.cfunc.argc); - } - break; case VM_METHOD_TYPE_UNDEF: break; case VM_METHOD_TYPE_REFINED:{ diff --git a/vm_method.c b/vm_method.c index a8efa15f7c..8ca3f936e4 100644 --- a/vm_method.c +++ b/vm_method.c @@ -420,7 +420,6 @@ rb_add_method(VALUE klass, ID mid, rb_method_type_t type, void *opts, rb_method_ def->body.iseq = (rb_iseq_t *)opts; break; case VM_METHOD_TYPE_CFUNC: - case VM_METHOD_TYPE_CFUNC_FRAMELESS: { rb_method_cfunc_t *cfunc = (rb_method_cfunc_t *)opts; setup_method_cfunc_struct(&def->body.cfunc, cfunc->func, cfunc->argc);