* bignum.c (rb_big_fdiv): checks whether the given second argument

can be converted to float properly.

	* numeric.c (fix_fdiv): calls rb_big_fdiv when the given second
	  argument is a bignum.

	* rational.c (nurat_fdiv): should calculate Float(x/y), not
	  Float(x)/Float(y).



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@23726 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,14 @@
+Wed Jun 17 21:25:54 2009  Tadayoshi Funaba  <tadf@dotrb.org>
+
+	* bignum.c (rb_big_fdiv): checks whether the given second argument
+	  can be converted to float properly.
+
+	* numeric.c (fix_fdiv): calls rb_big_fdiv when the given second
+	  argument is a bignum.
+
+	* rational.c (nurat_fdiv): should calculate Float(x/y), not
+	  Float(x)/Float(y).
+
 Wed Jun 17 16:57:40 2009  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* load.c (rb_f_require): RDoc updated.  a patch from Run Paint Run

bignum.c

@@ -2385,25 +2385,9 @@ big_shift(VALUE x, long n)
     return x;
 }
 
-/*
- *  call-seq:
-  *     big.fdiv(numeric) -> float
- *
- *  Returns the floating point result of dividing <i>big</i> by
- *  <i>numeric</i>.
- *
- *     -1234567890987654321.fdiv(13731)      #=> -89910996357705.5
- *     -1234567890987654321.fdiv(13731.24)   #=> -89909424858035.7
- *
- */
-
 static VALUE 
-rb_big_fdiv(VALUE x, VALUE y)
+big_fdiv(VALUE x, VALUE y)
 {
-    double dx = big2dbl(x);
-    double dy;
-
-    if (isinf(dx)) {
 #define DBL_BIGDIG ((DBL_MANT_DIG + BITSPERDIG) / BITSPERDIG)
     VALUE z;
     long l, ex, ey;
@@ -2439,23 +2423,52 @@ rb_big_fdiv(VALUE x, VALUE y)
 	  return DBL2NUM(ldexp(big2dbl(z), (int)l));
       }
       case T_FLOAT:
-	    if (isnan(RFLOAT_VALUE(y))) return y;
 	y = dbl2big(ldexp(frexp(RFLOAT_VALUE(y), &i), DBL_MANT_DIG));
 	ey = i - DBL_MANT_DIG;
 	goto bignum;
     }
-    }
+    rb_bug("big_fdiv");
+    /* NOTREACHED */
+}
+
+/*
+ *  call-seq:
+  *     big.fdiv(numeric) -> float
+ *
+ *  Returns the floating point result of dividing <i>big</i> by
+ *  <i>numeric</i>.
+ *
+ *     -1234567890987654321.fdiv(13731)      #=> -89910996357705.5
+ *     -1234567890987654321.fdiv(13731.24)   #=> -89909424858035.7
+ *
+ */
+
+
+VALUE
+rb_big_fdiv(VALUE x, VALUE y)
+{
+    double dx, dy;
+
+    dx = big2dbl(x);
     switch (TYPE(y)) {
       case T_FIXNUM:
 	dy = (double)FIX2LONG(y);
+	if (isinf(dx))
+	    return big_fdiv(x, y);
 	break;
 
       case T_BIGNUM:
 	dy = rb_big2dbl(y);
+	if (isinf(dx) || isinf(dy))
+	    return big_fdiv(x, y);
 	break;
 
       case T_FLOAT:
 	dy = RFLOAT_VALUE(y);
+	if (isnan(dy))
+	    return y;
+	if (isinf(dx))
+	    return big_fdiv(x, y);
 	break;
 
       default:

numeric.c

@@ -2269,6 +2269,8 @@ fixdivmod(long x, long y, long *divp, long *modp)
  *
  */
 
+VALUE rb_big_fdiv(VALUE x, VALUE y);
+
 static VALUE
 fix_fdiv(VALUE x, VALUE y)
 {
@@ -2277,7 +2279,7 @@ fix_fdiv(VALUE x, VALUE y)
     }
     switch (TYPE(y)) {
       case T_BIGNUM:
-	return DBL2NUM((double)FIX2LONG(x) / rb_big2dbl(y));
+	return rb_big_fdiv(rb_int2big(FIX2LONG(x)), y);
       case T_FLOAT:
 	return DBL2NUM((double)FIX2LONG(x) / RFLOAT_VALUE(y));
       default:

rational.c

@@ -769,7 +769,7 @@ nurat_div(VALUE self, VALUE other)
 static VALUE
 nurat_fdiv(VALUE self, VALUE other)
 {
-    return f_div(f_to_f(self), other);
+    return f_to_f(f_div(self, other));
 }
 
 static VALUE

test/ruby/test_bignum.rb

@@ -4,6 +4,9 @@ class TestBignum < Test::Unit::TestCase
   def setup
     @verbose = $VERBOSE
     $VERBOSE = nil
+    @fmax = Float::MAX.to_i
+    @fmax2 = @fmax * 2
+    @big = (1 << 63) - 1
   end
 
   def teardown
@@ -395,4 +398,19 @@ class TestBignum < Test::Unit::TestCase
     e = assert_raise(RangeError) {(1 << big).to_s}
     assert_match(/too big to convert/, e.message)
   end
+
+  def test_fix_fdiv
+    assert_not_equal(0, 1.fdiv(@fmax2))
+    assert_in_delta(0.5, 1.fdiv(@fmax2) * @fmax, 0.01)
+  end
+
+  def test_big_fdiv
+    assert_equal(1, @big.fdiv(@big))
+    assert_not_equal(0, @big.fdiv(@fmax2))
+    assert_not_equal(0, @fmax2.fdiv(@big))
+    assert_not_equal(0, @fmax2.fdiv(@fmax2))
+    assert_in_delta(0.5, @fmax.fdiv(@fmax2), 0.01)
+    assert_in_delta(1.0, @fmax2.fdiv(@fmax2), 0.01)
+  end
+
 end