diff options
| -rw-r--r-- | src/BigInt.cc | 64 |
1 files changed, 36 insertions, 28 deletions
diff --git a/src/BigInt.cc b/src/BigInt.cc index 7ff1422..73bfe29 100644 --- a/src/BigInt.cc +++ b/src/BigInt.cc @@ -11,8 +11,6 @@ class InitMP : public Balau::AtStart { InitMP() : AtStart(20) { } void doStart() { ltc_mp = ltm_desc; - IAssert(MP_DIGIT_BIT >= 32, "The code needs at least 32 bits digits."); - IAssert(MP_DIGIT_BIT <= 64, "The code needs at most 64 bits digits."); IAssert(!m_initialized, "doStart should only be called once."); m_initialized = true; @@ -136,45 +134,55 @@ void Balau::BigInt::set2expt(int i) throw (GeneralException) { } uint64_t Balau::BigInt::to_uint64() const throw (GeneralException) { - if (mp_get_digit_count(m_bi) > 2) + if (mp_count_bits(m_bi) > 64) throw GeneralException("BigInt too big to fit in a uint64"); - if (MP_DIGIT_BIT == 64) - return mp_get_digit(m_bi, 0); - uint64_t low = mp_get_digit(m_bi, 0); - uint64_t high = mp_get_digit(m_bi, 1); - uint64_t highest = 1 << (64 - MP_DIGIT_BIT); - if (high >= highest) - throw GeneralException("BigInt too big to fit in a uint64"); - return low | (high << MP_DIGIT_BIT); + uint64_t v = 0; + int shift = 0; + int digit = 0; + while (shift <= 64) { + v |= mp_get_digit(m_bi, digit++) << shift; + shift += MP_DIGIT_BIT; + } + return v; } int64_t Balau::BigInt::to_int64() const throw (GeneralException) { - uint64_t v = to_uint64(); - if (v & 0x8000000000000000ULL) + if (mp_count_bits(m_bi) > 63) throw GeneralException("BigInt too big to fit in a int64"); - if (comp(0) == LT) - return -v; - else - return v; + uint64_t v = 0; + int shift = 0; + int digit = 0; + while (shift <= 63) { + v |= mp_get_digit(m_bi, digit++) << shift; + shift += MP_DIGIT_BIT; + } + return comp(0) == LT ? -v : v; } uint32_t Balau::BigInt::to_uint32() const throw (GeneralException) { - if (mp_get_digit_count(m_bi) > 1) - throw GeneralException("BigInt too big to fit in a uint32"); - uint64_t v = mp_get_digit(m_bi, 0); - if (v >= 0x100000000ULL) + if (mp_count_bits(m_bi) > 32) throw GeneralException("BigInt too big to fit in a uint32"); + uint64_t v = 0; + int shift = 0; + int digit = 0; + while (shift <= 32) { + v |= mp_get_digit(m_bi, digit++) << shift; + shift += MP_DIGIT_BIT; + } return v; } int32_t Balau::BigInt::to_int32() const throw (GeneralException) { - uint32_t v = to_uint32(); - if (v & 0x80000000) - throw GeneralException("BigInt too big to fit in a int32"); - if (comp(0) == LT) - return -v; - else - return v; + if (mp_count_bits(m_bi) > 31) + throw GeneralException("BigInt too big to fit in a uint32"); + uint64_t v = 0; + int shift = 0; + int digit = 0; + while (shift <= 31) { + v |= mp_get_digit(m_bi, digit++) << shift; + shift += MP_DIGIT_BIT; + } + return comp(0) == LT ? -v : v; } Balau::BigInt Balau::BigInt::operator+(unsigned int i) const throw (GeneralException) { |