From 52de8260968cf77dda5980e632c94900f1487428 Mon Sep 17 00:00:00 2001 From: nobu Date: Sat, 20 May 2017 11:40:57 +0000 Subject: [PATCH] compile.c: optimize branches * compile.c (compile_branch_condition, iseq_compile_each0): eliminate unreachable branches in NODE_IF. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58815 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- compile.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) diff --git a/compile.c b/compile.c index bfdcb959ed..20b6c68d30 100644 --- a/compile.c +++ b/compile.c @@ -2909,6 +2909,7 @@ compile_branch_condition(rb_iseq_t *iseq, LINK_ANCHOR *const ret, NODE *cond, LABEL *label = NEW_LABEL(nd_line(cond)); CHECK(compile_branch_condition(iseq, ret, cond->nd_1st, label, else_label)); + if (!label->refcnt) break; ADD_LABEL(ret, label); cond = cond->nd_2nd; goto again; @@ -2918,6 +2919,7 @@ compile_branch_condition(rb_iseq_t *iseq, LINK_ANCHOR *const ret, NODE *cond, LABEL *label = NEW_LABEL(nd_line(cond)); CHECK(compile_branch_condition(iseq, ret, cond->nd_1st, then_label, label)); + if (!label->refcnt) break; ADD_LABEL(ret, label); cond = cond->nd_2nd; goto again; @@ -4250,7 +4252,7 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, NODE *node, int popp INIT_ANCHOR(else_seq); then_label = NEW_LABEL(line); else_label = NEW_LABEL(line); - end_label = NEW_LABEL(line); + end_label = 0; compile_branch_condition(iseq, cond_seq, node->nd_cond, then_label, else_label); @@ -4259,14 +4261,21 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, NODE *node, int popp ADD_SEQ(ret, cond_seq); - ADD_LABEL(ret, then_label); - ADD_SEQ(ret, then_seq); - ADD_INSNL(ret, line, jump, end_label); + if (then_label->refcnt) { + ADD_LABEL(ret, then_label); + ADD_SEQ(ret, then_seq); + end_label = NEW_LABEL(line); + ADD_INSNL(ret, line, jump, end_label); + } - ADD_LABEL(ret, else_label); - ADD_SEQ(ret, else_seq); + if (else_label->refcnt) { + ADD_LABEL(ret, else_label); + ADD_SEQ(ret, else_seq); + } - ADD_LABEL(ret, end_label); + if (end_label) { + ADD_LABEL(ret, end_label); + } break; }