* 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

@@ -2385,6 +2385,52 @@ big_shift(VALUE x, long n)
     return x;
 }
 
+static VALUE 
+big_fdiv(VALUE x, VALUE y)
+{
+#define DBL_BIGDIG ((DBL_MANT_DIG + BITSPERDIG) / BITSPERDIG)
+    VALUE z;
+    long l, ex, ey;
+    int i;
+
+    bigtrunc(x);
+    l = RBIGNUM_LEN(x) - 1;
+    ex = l * BITSPERDIG;
+    ex += bdigbitsize(BDIGITS(x)[l]);
+    ex -= 2 * DBL_BIGDIG * BITSPERDIG;
+    if (ex) x = big_shift(x, ex);
+
+    switch (TYPE(y)) {
+      case T_FIXNUM:
+	y = rb_int2big(FIX2LONG(y));
+      case T_BIGNUM: {
+	  bigtrunc(y);
+	  l = RBIGNUM_LEN(y) - 1;
+	  ey = l * BITSPERDIG;
+	  ey += bdigbitsize(BDIGITS(y)[l]);
+	  ey -= DBL_BIGDIG * BITSPERDIG;
+	  if (ey) y = big_shift(y, ey);
+	  bignum:
+	  bigdivrem(x, y, &z, 0);
+	  l = ex - ey;
+#if SIZEOF_LONG > SIZEOF_INT
+	  {
+	      /* Visual C++ can't be here */
+	      if (l > INT_MAX) return DBL2NUM(ruby_div0(1.0));
+	      if (l < INT_MIN) return DBL2NUM(0.0);
+	  }
+#endif
+	  return DBL2NUM(ldexp(big2dbl(z), (int)l));
+      }
+      case T_FLOAT:
+	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
@@ -2397,65 +2443,32 @@ big_shift(VALUE x, long n)
  *
  */
 
-static VALUE
+
+VALUE
 rb_big_fdiv(VALUE x, VALUE y)
 {
-    double dx = big2dbl(x);
+    double dx, dy;
-    double dy;
 
-    if (isinf(dx)) {
+    dx = big2dbl(x);
-#define DBL_BIGDIG ((DBL_MANT_DIG + BITSPERDIG) / BITSPERDIG)
-	VALUE z;
-	long l, ex, ey;
-	int i;
-
-	bigtrunc(x);
-	l = RBIGNUM_LEN(x) - 1;
-	ex = l * BITSPERDIG;
-	ex += bdigbitsize(BDIGITS(x)[l]);
-	ex -= 2 * DBL_BIGDIG * BITSPERDIG;
-	if (ex) x = big_shift(x, ex);
-
-	switch (TYPE(y)) {
-	  case T_FIXNUM:
-	    y = rb_int2big(FIX2LONG(y));
-	  case T_BIGNUM: {
-	    bigtrunc(y);
-	    l = RBIGNUM_LEN(y) - 1;
-	    ey = l * BITSPERDIG;
-	    ey += bdigbitsize(BDIGITS(y)[l]);
-	    ey -= DBL_BIGDIG * BITSPERDIG;
-	    if (ey) y = big_shift(y, ey);
-	  bignum:
-	    bigdivrem(x, y, &z, 0);
-	    l = ex - ey;
-#if SIZEOF_LONG > SIZEOF_INT
-	    {
-		/* Visual C++ can't be here */
-		if (l > INT_MAX) return DBL2NUM(ruby_div0(1.0));
-		if (l < INT_MIN) return DBL2NUM(0.0);
-	    }
-#endif
-	    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;
-	}
-    }
     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