Subject: [Boost-commit] svn:boost r78387 - in trunk: boost/polygon/detail libs/polygon/test
From: sydorchuk.andriy_at_[hidden]
Date: 2012-05-08 17:33:33
Author: asydorchuk
Date: 2012-05-08 17:33:33 EDT (Tue, 08 May 2012)
New Revision: 78387
URL: http://svn.boost.org/trac/boost/changeset/78387
Log:
Polygon: replacing exponent accessor structure of the voronoi coordinate types with calls to the frexp/ldexp.
Text files modified:
trunk/boost/polygon/detail/voronoi_ctypes.hpp | 170 +++++++++++++--------------------------
trunk/libs/polygon/test/voronoi_ctypes_test.cpp | 19 ----
2 files changed, 58 insertions(+), 131 deletions(-)
Modified: trunk/boost/polygon/detail/voronoi_ctypes.hpp
==============================================================================
--- trunk/boost/polygon/detail/voronoi_ctypes.hpp (original)
+++ trunk/boost/polygon/detail/voronoi_ctypes.hpp 2012-05-08 17:33:33 EDT (Tue, 08 May 2012)
@@ -65,143 +65,102 @@
}
};
-// Manages exponent of the floating-point value.
template <typename _fpt>
-struct fpt_exponent_accessor;
+struct extened_exponent_fpt_traits;
template <>
-class fpt_exponent_accessor<fpt64> {
+class extened_exponent_fpt_traits<fpt64> {
public:
- static const int64 kExponentMask;
- static const int64 kSignedMantissaMask;
- static const int64 kMinExponent;
- static const int64 kMaxExponent;
- static const int64 kMaxSignificantExpDif;
-
- static int64 set_exponent(fpt64& value, int64 exponent) {
- int64 bits;
- std::memcpy(&bits, &value, sizeof(fpt64));
- int64 exp = ((bits & kExponentMask) >> 52) - 1023;
- if (exp == exponent)
- return exp;
- bits = (bits & kSignedMantissaMask) | ((exponent + 1023) << 52);
- std::memcpy(&value, &bits, sizeof(fpt64));
- return exp;
- }
+ typedef int exp_type;
+ static const int kMaxSignificantExpDif;
};
-const int64 fpt_exponent_accessor<fpt64>::kExponentMask =
- 0x7ff0000000000000LL;
-const int64 fpt_exponent_accessor<fpt64>::kSignedMantissaMask =
- 0x800fffffffffffffLL;
-const int64 fpt_exponent_accessor<fpt64>::kMinExponent = -1023LL;
-const int64 fpt_exponent_accessor<fpt64>::kMaxExponent = 1024LL;
-const int64 fpt_exponent_accessor<fpt64>::kMaxSignificantExpDif = 54;
+const int extened_exponent_fpt_traits<fpt64>::kMaxSignificantExpDif = 54;
// Floating point type wrapper. Allows to extend exponent boundaries to the
-// 64 bit integer range. This class does not handle division by zero, subnormal
+// integer type range. This class does not handle division by zero, subnormal
// numbers or NaNs.
-template <typename _fpt>
+template <typename _fpt, typename _traits = extened_exponent_fpt_traits<_fpt> >
class extended_exponent_fpt {
public:
typedef _fpt fpt_type;
- typedef int64 exp_type;
- typedef fpt_exponent_accessor<fpt_type> fea;
+ typedef typename _traits::exp_type exp_type;
- explicit extended_exponent_fpt(fpt_type value) {
- if (value == 0.0) {
- exponent_ = 0;
- value_ = 0.0;
- } else {
- exponent_ = fea::set_exponent(value, 0);
- value_ = value;
- }
+ explicit extended_exponent_fpt(fpt_type val) {
+ val_ = std::frexp(val, &exp_);
}
- extended_exponent_fpt(fpt_type value, exp_type exponent) {
- if (value == 0.0) {
- exponent_ = 0;
- value_ = 0.0;
- } else {
- exponent_ = fea::set_exponent(value, 0) + exponent;
- value_ = value;
- }
+ extended_exponent_fpt(fpt_type val, exp_type exp) {
+ val_ = std::frexp(val, &exp_);
+ exp_ += exp;
}
bool is_pos() const {
- return value_ > 0;
+ return val_ > 0;
}
bool is_neg() const {
- return value_ < 0;
+ return val_ < 0;
}
bool is_zero() const {
- return value_ == 0;
+ return val_ == 0;
}
extended_exponent_fpt operator-() const {
- return extended_exponent_fpt(-value_, exponent_);
+ return extended_exponent_fpt(-val_, exp_);
}
extended_exponent_fpt operator+(const extended_exponent_fpt& that) const {
- if (this->value_ == 0.0 ||
- that.exponent_ > this->exponent_ + fea::kMaxSignificantExpDif) {
+ if (this->val_ == 0.0 ||
+ that.exp_ > this->exp_ + _traits::kMaxSignificantExpDif) {
return that;
}
- if (that.value_ == 0.0 ||
- this->exponent_ > that.exponent_ + fea::kMaxSignificantExpDif) {
+ if (that.val_ == 0.0 ||
+ this->exp_ > that.exp_ + _traits::kMaxSignificantExpDif) {
return *this;
}
- if (this->exponent_ >= that.exponent_) {
- exp_type exp_dif = this->exponent_ - that.exponent_;
- fpt_type value = this->value_;
- fea::set_exponent(value, exp_dif);
- value += that.value_;
- return extended_exponent_fpt(value, that.exponent_);
- } else {
- exp_type exp_dif = that.exponent_ - this->exponent_;
- fpt_type value = that.value_;
- fea::set_exponent(value, exp_dif);
- value += this->value_;
- return extended_exponent_fpt(value, this->exponent_);
+ if (this->exp_ >= that.exp_) {
+ exp_type exp_dif = this->exp_ - that.exp_;
+ fpt_type val = std::ldexp(this->val_, exp_dif) + that.val_;
+ return extended_exponent_fpt(val, that.exp_);
+ } else {
+ exp_type exp_dif = that.exp_ - this->exp_;
+ fpt_type val = std::ldexp(that.val_, exp_dif) + this->val_;
+ return extended_exponent_fpt(val, this->exp_);
}
}
extended_exponent_fpt operator-(const extended_exponent_fpt& that) const {
- if (this->value_ == 0.0 ||
- that.exponent_ > this->exponent_ + fea::kMaxSignificantExpDif) {
- return extended_exponent_fpt(-that.value_, that.exponent_);
+ if (this->val_ == 0.0 ||
+ that.exp_ > this->exp_ + _traits::kMaxSignificantExpDif) {
+ return extended_exponent_fpt(-that.val_, that.exp_);
}
- if (that.value_ == 0.0 ||
- this->exponent_ > that.exponent_ + fea::kMaxSignificantExpDif) {
+ if (that.val_ == 0.0 ||
+ this->exp_ > that.exp_ + _traits::kMaxSignificantExpDif) {
return *this;
}
- if (this->exponent_ >= that.exponent_) {
- exp_type exp_dif = this->exponent_ - that.exponent_;
- fpt_type value = this->value_;
- fea::set_exponent(value, exp_dif);
- value -= that.value_;
- return extended_exponent_fpt(value, that.exponent_);
- } else {
- exp_type exp_dif = that.exponent_ - this->exponent_;
- fpt_type value = -that.value_;
- fea::set_exponent(value, exp_dif);
- value += this->value_;
- return extended_exponent_fpt(value, this->exponent_);
+ if (this->exp_ >= that.exp_) {
+ exp_type exp_dif = this->exp_ - that.exp_;
+ fpt_type val = std::ldexp(this->val_, exp_dif) - that.val_;
+ return extended_exponent_fpt(val, that.exp_);
+ } else {
+ exp_type exp_dif = that.exp_ - this->exp_;
+ fpt_type val = std::ldexp(-that.val_, exp_dif) + this->val_;
+ return extended_exponent_fpt(val, this->exp_);
}
}
extended_exponent_fpt operator*(const extended_exponent_fpt& that) const {
- fpt_type value = this->value_ * that.value_;
- exp_type exponent = this->exponent_ + that.exponent_;
- return extended_exponent_fpt(value, exponent);
+ fpt_type val = this->val_ * that.val_;
+ exp_type exp = this->exp_ + that.exp_;
+ return extended_exponent_fpt(val, exp);
}
extended_exponent_fpt operator/(const extended_exponent_fpt& that) const {
- fpt_type value = this->value_ / that.value_;
- exp_type exponent = this->exponent_ - that.exponent_;
- return extended_exponent_fpt(value, exponent);
+ fpt_type val = this->val_ / that.val_;
+ exp_type exp = this->exp_ - that.exp_;
+ return extended_exponent_fpt(val, exp);
}
extended_exponent_fpt& operator+=(const extended_exponent_fpt& that) {
@@ -221,8 +180,8 @@
}
extended_exponent_fpt sqrt() const {
- fpt_type val = value_;
- exp_type exp = exponent_;
+ fpt_type val = val_;
+ exp_type exp = exp_;
if (exp & 1) {
val *= 2.0;
--exp;
@@ -231,24 +190,12 @@
}
fpt_type d() const {
- fpt_type ret_val = value_;
- exp_type exp = exponent_;
- if (ret_val == 0.0)
- return ret_val;
- if (exp >= fea::kMaxExponent) {
- ret_val = 1.0;
- exp = fea::kMaxExponent;
- } else if (exp <= fea::kMinExponent) {
- ret_val = 1.0;
- exp = fea::kMinExponent;
- }
- fea::set_exponent(ret_val, exp);
- return ret_val;
+ return std::ldexp(val_, exp_);
}
private:
- fpt_type value_;
- exp_type exponent_;
+ fpt_type val_;
+ exp_type exp_;
};
typedef extended_exponent_fpt<double> efpt64;
@@ -521,8 +468,8 @@
return (std::abs)(count_);
}
- std::pair<fpt64, int64> p() const {
- std::pair<fpt64, int64> ret_val(0, 0);
+ std::pair<fpt64, int> p() const {
+ std::pair<fpt64, int> ret_val(0, 0);
size_t sz = this->size();
if (!sz) {
return ret_val;
@@ -547,9 +494,8 @@
}
fpt64 d() const {
- std::pair<fpt64, int64> p = this->p();
- extended_exponent_fpt<fpt64> efpt(p.first, p.second);
- return efpt.d();
+ std::pair<fpt64, int> p = this->p();
+ return std::ldexp(p.first, p.second);
}
private:
@@ -683,7 +629,7 @@
struct type_converter_efpt {
template <size_t N>
extended_exponent_fpt<fpt64> operator()(const extended_int<N>& that) const {
- std::pair<fpt64, int64> p = that.p();
+ std::pair<fpt64, int> p = that.p();
return extended_exponent_fpt<fpt64>(p.first, p.second);
}
};
Modified: trunk/libs/polygon/test/voronoi_ctypes_test.cpp
==============================================================================
--- trunk/libs/polygon/test/voronoi_ctypes_test.cpp (original)
+++ trunk/libs/polygon/test/voronoi_ctypes_test.cpp 2012-05-08 17:33:33 EDT (Tue, 08 May 2012)
@@ -46,25 +46,6 @@
BOOST_CHECK_EQUAL(ulp_cmp(da, db, 3), ulp_cmp.EQUAL);
}
-BOOST_AUTO_TEST_CASE(fpt_exponent_accessor_test) {
- typedef fpt_exponent_accessor<fpt64> fpt_ea;
- fpt64 value = 15;
- BOOST_CHECK_EQUAL(fpt_ea::set_exponent(value, 0), 3);
- BOOST_CHECK_EQUAL(value, 1.875);
- value = 0.0625;
- BOOST_CHECK_EQUAL(fpt_ea::set_exponent(value, 0), -4);
- BOOST_CHECK_EQUAL(value, 1.0);
- value = -1.5;
- BOOST_CHECK_EQUAL(fpt_ea::set_exponent(value, 4), 0);
- BOOST_CHECK_EQUAL(value, -24.0);
- value = 0.0;
- BOOST_CHECK_EQUAL(fpt_ea::set_exponent(value, 4), fpt_ea::kMinExponent);
- BOOST_CHECK_EQUAL(value, 16.0);
- value = std::pow(2.0, 2000);
- BOOST_CHECK_EQUAL(fpt_ea::set_exponent(value, 4), fpt_ea::kMaxExponent);
- BOOST_CHECK_EQUAL(value, 16.0);
-}
-
BOOST_AUTO_TEST_CASE(extended_exponent_fpt_test1) {
boost::mt19937_64 gen(static_cast<uint32>(time(NULL)));
fpt64 b = 0.0;