Changeset 994 for trunk/src/real.cppTweet

Timestamp:

Sep 28, 2011, 7:04:44 PM (11 years ago)

Author:

sam

Message:

core: implement shift operators for reals; they're useful for fast
multiplications by integers, especially powers of two.

File:

• trunk/src/real.cpp (modified) (2 diffs)

trunk/src/real.cpp

@@ -349 +349 @@
     real tmp = *this;
     return *this = tmp / x;
+}
+
+real real::operator <<(int x) const
+{
+    real tmp = *this;
+    return tmp <<= x;
+}
+
+real real::operator >>(int x) const
+{
+    real tmp = *this;
+    return tmp >>= x;
+}
+
+real &real::operator <<=(int x)
+{
+    if (m_signexp << 1)
+        m_signexp += x;
+    return *this;
+}
+
+real &real::operator >>=(int x)
+{
+    if (m_signexp << 1)
+        m_signexp -= x;
+    return *this;
 }
 
@@ -542 +568 @@
     }
 
-    /* FIXME: sum.m_signexp += 2; (but needs private data access) */
-    sum *= (real)4;
-    return z * sum;
+    return z * (sum << 2);
 }