From 0b89d6d5f9f8c788f4391d8a0499f10aed624371 Mon Sep 17 00:00:00 2001

From: ko1 <ko1@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>

Date: Mon, 27 Aug 2012 09:22:21 +0000

Subject: [PATCH] * include/ruby/ruby.h (rb_float_value): optimize it.   This

 technique was pointed by shinichiro.hamaji  

 <http://shinh.skr.jp/m/?date=20120825#p02>.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@36832 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

---

 ChangeLog           |    6 ++++++

 include/ruby/ruby.h |   10 +++++-----

 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/include/ruby/ruby.h b/include/ruby/ruby.h

index 3905b32..b8b2267 100644

--- a/include/ruby/ruby.h

+++ b/include/ruby/ruby.h

@@ -733,10 +733,7 @@ struct RFloat {

 rb_float_value(VALUE v)

 {

     if (FLONUM_P(v)) {

-	if (v == (VALUE)0x8000000000000002) {

-	    return 0.0;

-	}

-	else {

+	if (v != (VALUE)0x8000000000000002) { /* LIKELY */

 	    union {

 		double d;

 		VALUE v;

@@ -746,9 +743,12 @@ struct RFloat {

 	    /* e: xx1... -> 011... */

 	    /*    xx0... -> 100... */

 	    /*      ^b63           */

-	    t.v = RUBY_BIT_ROTR(((b63 ^ 1) << 1) | b63 | (v & ~0x03), 3);

+	    t.v = RUBY_BIT_ROTR(2 - b63 | (v & ~0x03), 3);

 	    return t.d;

 	}

+	else {

+	    return 0.0;

+	}

     }

     else {

 	return ((struct RFloat *)v)->float_value;

-- 

1.7.10