From d8769bffe590bad0a9d65cb796c622fb819feeb2 Mon Sep 17 00:00:00 2001
From: mrkn <mrkn@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Fri, 11 Nov 2016 16:38:28 +0000
Subject: [PATCH] rational.c: optimize Rational#**

* rational.c (nurat_expt): optimize Rational#**.
  Author: Tadashi Saito <tad.a.digger@gmail.com>

* numeric.c (rb_float_pow): rename flo_pow() to rb_float_pow()
  and remove static to be exporetd.

* internal.h (rb_int_pow, rb_float_pow): exported.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56725 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 internal.h |  2 ++
 numeric.c  |  8 ++++----
 rational.c | 14 ++++++++------
 3 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/internal.h b/internal.h
index be3694ecc6..067d35885c 100644
--- a/internal.h
+++ b/internal.h
@@ -1171,6 +1171,8 @@ VALUE rb_fix_plus(VALUE x, VALUE y);
 VALUE rb_int_ge(VALUE x, VALUE y);
 enum ruby_num_rounding_mode rb_num_get_rounding_option(VALUE opts);
 double rb_int_fdiv_double(VALUE x, VALUE y);
+VALUE rb_int_pow(VALUE x, VALUE y);
+VALUE rb_float_pow(VALUE x, VALUE y);
 
 #if USE_FLONUM
 #define RUBY_BIT_ROTL(v, n) (((v) << (n)) | ((v) >> ((sizeof(v) * 8) - n)))
diff --git a/numeric.c b/numeric.c
index 8df969eb49..0a50687776 100644
--- a/numeric.c
+++ b/numeric.c
@@ -1291,8 +1291,8 @@ flo_divmod(VALUE x, VALUE y)
  *    2.0**3      #=> 8.0
  */
 
-static VALUE
-flo_pow(VALUE x, VALUE y)
+VALUE
+rb_float_pow(VALUE x, VALUE y)
 {
     double dx, dy;
     if (RB_TYPE_P(y, T_FIXNUM)) {
@@ -3931,7 +3931,7 @@ fix_pow(VALUE x, VALUE y)
     }
 }
 
-static VALUE
+VALUE
 rb_int_pow(VALUE x, VALUE y)
 {
     if (FIXNUM_P(x)) {
@@ -5395,7 +5395,7 @@ Init_Numeric(void)
     rb_define_method(rb_cFloat, "%", flo_mod, 1);
     rb_define_method(rb_cFloat, "modulo", flo_mod, 1);
     rb_define_method(rb_cFloat, "divmod", flo_divmod, 1);
-    rb_define_method(rb_cFloat, "**", flo_pow, 1);
+    rb_define_method(rb_cFloat, "**", rb_float_pow, 1);
     rb_define_method(rb_cFloat, "==", flo_eq, 1);
     rb_define_method(rb_cFloat, "===", flo_eq, 1);
     rb_define_method(rb_cFloat, "<=>", flo_cmp, 1);
diff --git a/rational.c b/rational.c
index 210a721b17..4592178b7f 100644
--- a/rational.c
+++ b/rational.c
@@ -966,6 +966,8 @@ f_odd_p(VALUE integer)
     return Qfalse;
 }
 
+static VALUE nurat_to_f(VALUE self);
+
 /*
  * call-seq:
  *    rat ** numeric  ->  numeric
@@ -1022,12 +1024,12 @@ nurat_expt(VALUE self, VALUE other)
 
 	    switch (FIX2INT(f_cmp(other, ZERO))) {
 	      case 1:
-		num = f_expt(dat->num, other);
-		den = f_expt(dat->den, other);
+		num = rb_int_pow(dat->num, other);
+		den = rb_int_pow(dat->den, other);
 		break;
 	      case -1:
-		num = f_expt(dat->den, f_negate(other));
-		den = f_expt(dat->num, f_negate(other));
+		num = rb_int_pow(dat->den, rb_int_uminus(other));
+		den = rb_int_pow(dat->num, rb_int_uminus(other));
 		break;
 	      default:
 		num = ONE;
@@ -1039,10 +1041,10 @@ nurat_expt(VALUE self, VALUE other)
     }
     else if (RB_TYPE_P(other, T_BIGNUM)) {
 	rb_warn("in a**b, b may be too big");
-	return f_expt(f_to_f(self), other);
+	return rb_float_pow(nurat_to_f(self), other);
     }
     else if (RB_TYPE_P(other, T_FLOAT) || RB_TYPE_P(other, T_RATIONAL)) {
-	return f_expt(f_to_f(self), other);
+	return rb_float_pow(nurat_to_f(self), other);
     }
     else {
 	return rb_num_coerce_bin(self, other, id_expt);