BigNum.cxx File Reference

#include <assert.h>
#include <string>
#include <string.h>
#include <libsherpa/BigNum.hxx>
#include <libsherpa/UExcept.hxx>

Go to the source code of this file.

Namespaces
namespace	sherpa
Data Structures
struct	sherpa::nvec
Functions
static void *	rmemset (void *s, int c, size_t n)
	memset, but initializing from top to bottom.
static uint32_t	max (uint32_t a, uint32_t b)
static uint32_t	min (uint32_t a, uint32_t b)
static int	sherpa::vu_cmp (const nvec n1, const nvec n2)
	compare two digit vectors for relative magnitude. Return -1, 0, 1 according to whether v1 is less than, equal to, or greater than v2.
static void	sherpa::vu_rshift_digits (const nvec n1, size_t nShift, nvec n2)
	n2 = n1 / (radix^nShift)
static void	sherpa::vu_lshift_digits (const nvec n1, size_t nShift, nvec n2)
	n2 = n1 * (radix^nShift)
static void	sherpa::vu_rshift_bits (const nvec n1, size_t nShift, nvec n2)
	n2 = n1 >> nShift
static void	sherpa::vu_lshift_bits (const nvec n1, size_t nShift, nvec n2)
	n2 = n1 << nShift
static unsigned	sherpa::vu_get_bit (const nvec n1, size_t bit)
static void	sherpa::vu_set_bit (nvec n1, size_t bit)
static void	sherpa::vu_clear_bit (nvec n1, size_t bit)
static void	sherpa::vu_copy (const nvec n1, nvec n2)
static void	sherpa::vu_sub (const nvec n1, const nvec n2, nvec n3)
	Subtract: n3 = n1 - n2.
static void	sherpa::vu_add (const nvec n1, const nvec n2, nvec n3)
	Add: n3 = n1 + n2.
static void	sherpa::vu_mul (const nvec n1, const nvec n2, nvec n3)
	Multiply: n3 = n1 * n2.
static void	sherpa::vu_divqr (const nvec dividend, const nvec divisor, nvec quotient, nvec remainder)
	Divide q = n1 / n2, r = (n1 - (n2 * q)).
Variables
const uint64_t	UINT32_T_MAX = 4294967295ull
static uint32_t	sherpa::u_zero = 0
static const nvec	sherpa::nv_zero (1,&u_zero)
static uint32_t	sherpa::u_one = 1
static const nvec	sherpa::nv_one (1,&u_one)

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Function Documentation

static uint32_t max	(	uint32_t	a,
		uint32_t	b
	)			[inline, static]

Definition at line 65 of file BigNum.cxx.

Referenced by calc_unin_size(), sherpa::BigNum::operator+(), sherpa::BigNum::operator-(), and sherpa::vu_cmp().

static uint32_t min	(	uint32_t	a,
		uint32_t	b
	)			[inline, static]

Definition at line 70 of file BigNum.cxx.

Referenced by sherpa::vu_lshift_bits(), sherpa::vu_lshift_digits(), and sherpa::vu_rshift_digits().

static void* rmemset	(	void *	s,
		int	c,
		size_t	n
	)			[static]

memset, but initializing from top to bottom.

In large heap-allocated vectors a segv can occur if a reference occurs too far below bottom of stack. The easiest way to prevent this is to touch the bytes in the proper order.

Definition at line 56 of file BigNum.cxx.

Referenced by sherpa::vu_divqr(), and sherpa::vu_mul().

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Variable Documentation

const uint64_t UINT32_T_MAX = 4294967295ull

Definition at line 48 of file BigNum.cxx.

Referenced by sherpa::BigNum::BigNum(), and sherpa::vu_sub().

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