Subject: [Boost-commit] svn:boost r76434 - sandbox/big_number/boost/multiprecision
From: john_at_[hidden]
Date: 2012-01-12 12:03:28
Author: johnmaddock
Date: 2012-01-12 12:03:27 EST (Thu, 12 Jan 2012)
New Revision: 76434
URL: http://svn.boost.org/trac/boost/changeset/76434
Log:
Optimize increment and decrement.
Text files modified:
sandbox/big_number/boost/multiprecision/fixed_int.hpp | 14 ++++++++++++--
1 files changed, 12 insertions(+), 2 deletions(-)
Modified: sandbox/big_number/boost/multiprecision/fixed_int.hpp
==============================================================================
--- sandbox/big_number/boost/multiprecision/fixed_int.hpp (original)
+++ sandbox/big_number/boost/multiprecision/fixed_int.hpp 2012-01-12 12:03:27 EST (Thu, 12 Jan 2012)
@@ -424,13 +424,19 @@
inline void increment(fixed_int<Bits, Signed>& result)
{
static const limb_type one = 1;
- add(result, one);
+ if(result.data().elems[fixed_int<Bits, Signed>::limb_count - 1] < fixed_int<Bits, Signed>::max_limb_value)
+ ++result.data().elems[fixed_int<Bits, Signed>::limb_count - 1];
+ else
+ add(result, one);
}
template <unsigned Bits, bool Signed>
inline void decrement(fixed_int<Bits, Signed>& result)
{
static const limb_type one = 1;
- subtract(result, one);
+ if(result.data().elems[fixed_int<Bits, Signed>::limb_count - 1])
+ --result.data().elems[fixed_int<Bits, Signed>::limb_count - 1];
+ else
+ subtract(result, one);
}
template <unsigned Bits, bool Signed>
inline void subtract(fixed_int<Bits, Signed>& result, const fixed_int<Bits, Signed>& o)
@@ -720,6 +726,8 @@
return;
}
+ //fixed_int<Bits, Signed> last_r;
+ //bool last_neg;
do
{
//
@@ -731,6 +739,8 @@
// Calculate our best guess for how many times y divides into r:
//
limb_type guess;
+ //last_r = r;
+ //last_neg = r_neg;
if((r.data()[r_order] <= y.data()[y_order]) && (r_order < fixed_int<Bits, Signed>::limb_count - 1))
{
double_limb_type a, b, v;