From 2ffa6f3f1616d7db3503600ac047a10b01a6bb54 Mon Sep 17 00:00:00 2001
From: lloyd <lloyd@randombit.net>
Date: Thu, 19 Nov 2009 18:03:17 +0000
Subject: Add move assignment and constructor operators to BigInt. On macro
 benchmarks (timing the test suite) there doesn't seem to be much of a
 difference either way, but putting printfs in the implementations shows they
 are being used. Since they pretty much can't possibly hurt (right?) and might
 well help a lot in certain cases, it's worth including.

Todo: adding overloads to binary operators taking move operations might
be nice. Details in http://cpp-next.com/archive/2009/09/making-your-next-move/
---
 src/math/bigint/bigint.cpp | 25 ++++++++++++++++++++++++-
 src/math/bigint/bigint.h   | 19 ++++++++++++++++---
 2 files changed, 40 insertions(+), 4 deletions(-)

(limited to 'src/math/bigint')

diff --git a/src/math/bigint/bigint.cpp b/src/math/bigint/bigint.cpp
index 7592ec439..36739f047 100644
--- a/src/math/bigint/bigint.cpp
+++ b/src/math/bigint/bigint.cpp
@@ -40,7 +40,7 @@ BigInt::BigInt(Sign s, u32bit size)
    }
 
 /*
-* Construct a BigInt from a "raw" BigInt
+* Copy constructor
 */
 BigInt::BigInt(const BigInt& b)
    {
@@ -100,6 +100,29 @@ BigInt::BigInt(RandomNumberGenerator& rng, u32bit bits)
    randomize(rng, bits);
    }
 
+/**
+* Move constructor
+*/
+BigInt::BigInt(BigInt&& other)
+   {
+   reg.swap(other.reg);
+   signedness = other.signedness;
+   }
+
+/**
+* Move assignment
+*/
+BigInt& BigInt::operator=(BigInt&& other)
+   {
+   if(this != &other)
+      {
+      reg.swap(other.reg);
+      signedness = other.signedness;
+      }
+
+   return (*this);
+   }
+
 /*
 * Swap this BigInt with another
 */
diff --git a/src/math/bigint/bigint.h b/src/math/bigint/bigint.h
index 4f7f6f5bd..3db9a1a04 100644
--- a/src/math/bigint/bigint.h
+++ b/src/math/bigint/bigint.h
@@ -425,10 +425,14 @@ class BOTAN_DLL BigInt
      BigInt(u64bit n);
 
      /**
-     * Copy-Constructor: clone given BigInt
-     * @param bigint the BigInt to clone
+     * Copy constructor
      */
-     BigInt(const BigInt& bigint);
+     BigInt(const BigInt& other);
+
+     /**
+     * Assignment operator
+     */
+     BigInt& operator=(const BigInt&) = default;
 
      /**
      * Create BigInt from a string.
@@ -471,6 +475,15 @@ class BOTAN_DLL BigInt
      */
      BigInt(NumberType type, u32bit n);
 
+     /**
+     * Move constructor
+     */
+     BigInt(BigInt&& other);
+
+     /**
+     * Move assignment
+     */
+     BigInt& operator=(BigInt&& other);
    private:
       SecureVector<word> reg;
       Sign signedness;
-- 
cgit v1.2.3


From bab01ef1514266e6f23d9163e503c115147ab993 Mon Sep 17 00:00:00 2001
From: lloyd <lloyd@randombit.net>
Date: Thu, 19 Nov 2009 18:12:32 +0000
Subject: Define move assignment and constructors in terms of std::swap (which
 boils down to BigInt::swap, which uses the memvec swap). Checking with g++
 4.5 -O3 shows it compiles down the same code as before.

---
 src/math/bigint/bigint.cpp | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

(limited to 'src/math/bigint')

diff --git a/src/math/bigint/bigint.cpp b/src/math/bigint/bigint.cpp
index 36739f047..c777e770b 100644
--- a/src/math/bigint/bigint.cpp
+++ b/src/math/bigint/bigint.cpp
@@ -105,8 +105,7 @@ BigInt::BigInt(RandomNumberGenerator& rng, u32bit bits)
 */
 BigInt::BigInt(BigInt&& other)
    {
-   reg.swap(other.reg);
-   signedness = other.signedness;
+   std::swap(*this, other);
    }
 
 /**
@@ -115,10 +114,7 @@ BigInt::BigInt(BigInt&& other)
 BigInt& BigInt::operator=(BigInt&& other)
    {
    if(this != &other)
-      {
-      reg.swap(other.reg);
-      signedness = other.signedness;
-      }
+      std::swap(*this, other);
 
    return (*this);
    }
-- 
cgit v1.2.3