rational.c: avoid needless object allocation with nurat_to_double

* rational.c (nurat_to_double): introduce to convert rational to double
  without object allocation.

* rational.c (rb_rational_plus, nurat_{sub,mul,to_f}): rewrite by using
  nurat_to_double.

* bignum.c (rb_big_fdiv_double): introduce to calculate fdiv and return
  the result as a double value.

* bignum.c (big_fdiv{,_int,_float}): change the return types for
  implementing rb_big_fdiv_double.

* bignum.c (rb_big_fdiv): rewrite by using rb_big_fdiv_double.

* numeric.c (rb_int_fdiv_double): introduce to calculate fdiv and return
  the result as a double value.

* numeric.c (fix_fdiv_double): rewrite from fix_fdiv to return the
  result as a double value.

* numeric.c (rb_int_fdiv): rewrite by using rb_int_fdiv_double.

* internal.h (rb_{big,int}_fdiv_double): exported.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56719 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

bignum.c

@@ -6090,7 +6090,7 @@ big_shift(VALUE x, long n)
     return x;
 }
 
-static VALUE
+static double
 big_fdiv(VALUE x, VALUE y, long ey)
 {
 #define DBL_BIGDIG ((DBL_MANT_DIG + BITSPERDIG) / BITSPERDIG)
@@ -6108,14 +6108,14 @@ big_fdiv(VALUE x, VALUE y, long ey)
 #if SIZEOF_LONG > SIZEOF_INT
     {
 	/* Visual C++ can't be here */
-	if (l > INT_MAX) return DBL2NUM(INFINITY);
+	if (l > INT_MAX) return INFINITY;
-	if (l < INT_MIN) return DBL2NUM(0.0);
+	if (l < INT_MIN) return 0.0;
     }
 #endif
-    return DBL2NUM(ldexp(big2dbl(z), (int)l));
+    return ldexp(big2dbl(z), (int)l);
 }
 
-static VALUE
+static double
 big_fdiv_int(VALUE x, VALUE y)
 {
     long l, ey;
@@ -6127,7 +6127,7 @@ big_fdiv_int(VALUE x, VALUE y)
     return big_fdiv(x, y, ey);
 }
 
-static VALUE
+static double
 big_fdiv_float(VALUE x, VALUE y)
 {
     int i;
@@ -6135,8 +6135,8 @@ big_fdiv_float(VALUE x, VALUE y)
     return big_fdiv(x, y, i - DBL_MANT_DIG);
 }
 
-VALUE
+double
-rb_big_fdiv(VALUE x, VALUE y)
+rb_big_fdiv_double(VALUE x, VALUE y)
 {
     double dx, dy;
 
@@ -6154,14 +6154,20 @@ rb_big_fdiv(VALUE x, VALUE y)
     else if (RB_FLOAT_TYPE_P(y)) {
 	dy = RFLOAT_VALUE(y);
 	if (isnan(dy))
-	    return y;
+	    return dy;
 	if (isinf(dx))
 	    return big_fdiv_float(x, y);
     }
     else {
-	return rb_num_coerce_bin(x, y, rb_intern("fdiv"));
+	return RFLOAT_VALUE(rb_num_coerce_bin(x, y, rb_intern("fdiv")));
     }
-    return DBL2NUM(dx / dy);
+    return dx / dy;
+}
+
+VALUE
+rb_big_fdiv(VALUE x, VALUE y)
+{
+    return DBL2NUM(rb_big_fdiv_double(x, y));
 }
 
 VALUE

internal.h

@@ -891,7 +891,7 @@ size_t rb_ary_memsize(VALUE);
 
 /* bignum.c */
 extern const char ruby_digitmap[];
-VALUE rb_big_fdiv(VALUE x, VALUE y);
+double rb_big_fdiv_double(VALUE x, VALUE y);
 VALUE rb_big_uminus(VALUE x);
 VALUE rb_big_hash(VALUE);
 VALUE rb_big_odd_p(VALUE);
@@ -1170,7 +1170,7 @@ VALUE rb_dbl_hash(double d);
 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);
-VALUE rb_int_fdiv(VALUE x, VALUE y);
+double rb_int_fdiv_double(VALUE x, VALUE y);
 
 #if USE_FLONUM
 #define RUBY_BIT_ROTL(v, n) (((v) << (n)) | ((v) >> ((sizeof(v) * 8) - n)))

numeric.c

@@ -3549,6 +3549,35 @@ rb_int_mul(VALUE x, VALUE y)
     return rb_num_coerce_bin(x, y, '*');
 }
 
+static double
+fix_fdiv_double(VALUE x, VALUE y)
+{
+    if (FIXNUM_P(y)) {
+        return (double)FIX2LONG(x) / (double)FIX2LONG(y);
+    }
+    else if (RB_TYPE_P(y, T_BIGNUM)) {
+        return rb_big_fdiv_double(rb_int2big(FIX2LONG(x)), y);
+    }
+    else if (RB_TYPE_P(y, T_FLOAT)) {
+        return (double)FIX2LONG(x) / RFLOAT_VALUE(y);
+    }
+    else {
+        return RFLOAT_VALUE(rb_num_coerce_bin(x, y, rb_intern("fdiv")));
+    }
+}
+
+double
+rb_int_fdiv_double(VALUE x, VALUE y)
+{
+    if (FIXNUM_P(x)) {
+        return fix_fdiv_double(x, y);
+    }
+    else if (RB_TYPE_P(x, T_BIGNUM)) {
+        return rb_big_fdiv_double(x, y);
+    }
+    return NAN;
+}
+
 /*
  *  Document-method: Integer#fdiv
  *  call-seq:
@@ -3564,31 +3593,11 @@ rb_int_mul(VALUE x, VALUE y)
  *
  */
 
-static VALUE
-fix_fdiv(VALUE x, VALUE y)
-{
-    if (FIXNUM_P(y)) {
-	return DBL2NUM((double)FIX2LONG(x) / (double)FIX2LONG(y));
-    }
-    else if (RB_TYPE_P(y, T_BIGNUM)) {
-	return rb_big_fdiv(rb_int2big(FIX2LONG(x)), y);
-    }
-    else if (RB_TYPE_P(y, T_FLOAT)) {
-	return DBL2NUM((double)FIX2LONG(x) / RFLOAT_VALUE(y));
-    }
-    else {
-	return rb_num_coerce_bin(x, y, rb_intern("fdiv"));
-    }
-}
-
 VALUE
 rb_int_fdiv(VALUE x, VALUE y)
 {
-    if (FIXNUM_P(x)) {
+    if (RB_INTEGER_TYPE_P(x)) {
-	return fix_fdiv(x, y);
+        return DBL2NUM(rb_int_fdiv_double(x, y));
-    }
-    else if (RB_TYPE_P(x, T_BIGNUM)) {
-	return rb_big_fdiv(x, y);
     }
     return Qnil;
 }

rational.c

@@ -721,7 +721,7 @@ f_addsub(VALUE self, VALUE anum, VALUE aden, VALUE bnum, VALUE bden, int k)
     return f_rational_new_no_reduce2(CLASS_OF(self), num, den);
 }
 
-static VALUE nurat_to_f(VALUE self);
+static double nurat_to_double(VALUE self);
 /*
  * call-seq:
  *    rat + numeric  ->  numeric
@@ -747,7 +747,7 @@ rb_rational_plus(VALUE self, VALUE other)
 	}
     }
     else if (RB_TYPE_P(other, T_FLOAT)) {
-	return DBL2NUM(RFLOAT_VALUE(nurat_to_f(self)) + RFLOAT_VALUE(other));
+	return DBL2NUM(nurat_to_double(self) + RFLOAT_VALUE(other));
     }
     else if (RB_TYPE_P(other, T_RATIONAL)) {
 	{
@@ -788,7 +788,7 @@ nurat_sub(VALUE self, VALUE other)
 	}
     }
     else if (RB_FLOAT_TYPE_P(other)) {
-	return DBL2NUM(RFLOAT_VALUE(nurat_to_f(self)) - RFLOAT_VALUE(other));
+	return DBL2NUM(nurat_to_double(self) - RFLOAT_VALUE(other));
     }
     else if (RB_TYPE_P(other, T_RATIONAL)) {
 	{
@@ -868,7 +868,7 @@ nurat_mul(VALUE self, VALUE other)
 	}
     }
     else if (RB_FLOAT_TYPE_P(other)) {
-	return DBL2NUM(RFLOAT_VALUE(nurat_to_f(self)) * RFLOAT_VALUE(other));
+	return DBL2NUM(nurat_to_double(self) * RFLOAT_VALUE(other));
     }
     else if (RB_TYPE_P(other, T_RATIONAL)) {
 	{
@@ -1433,6 +1433,13 @@ nurat_round_n(int argc, VALUE *argv, VALUE self)
     return f_round_common(argc, argv, self, round_func);
 }
 
+static double
+nurat_to_double(VALUE self)
+{
+    get_dat1(self);
+    return rb_int_fdiv_double(dat->num, dat->den);
+}
+
 /*
  * call-seq:
  *    rat.to_f  ->  float
@@ -1447,8 +1454,7 @@ nurat_round_n(int argc, VALUE *argv, VALUE self)
 static VALUE
 nurat_to_f(VALUE self)
 {
-    get_dat1(self);
+    return DBL2NUM(nurat_to_double(self));
-    return rb_int_fdiv(dat->num, dat->den);
 }
 
 /*