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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// Define a hexfloat literal emulator since we can't depend on being able to
// for hexfloat literals
// 0x10.F5p-10 == hexfloat<double>(0x10, 0xF5, -10)
#ifndef HEXFLOAT_H
#define HEXFLOAT_H
#include <cmath>
#include <climits>
template <class T>
class hexfloat
{
T value_;
static int CountLeadingZeros(unsigned long long n) {
const std::size_t Digits = sizeof(unsigned long long) * CHAR_BIT;
const unsigned long long TopBit = 1ull << (Digits - 1);
if (n == 0) return Digits;
int LeadingZeros = 0;
while ((n & TopBit) == 0) {
++LeadingZeros;
n <<= 1;
}
return LeadingZeros;
}
public:
hexfloat(long long m1, unsigned long long m0, int exp)
{
const std::size_t Digits = sizeof(unsigned long long) * CHAR_BIT;
int s = m1 < 0 ? -1 : 1;
int exp2 = -static_cast<int>(Digits - CountLeadingZeros(m0)/4*4);
value_ = std::ldexp(m1 + s * std::ldexp(T(m0), exp2), exp);
}
operator T() const {return value_;}
};
#endif
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