Basics::BigInt Struct Reference

Collaboration diagram for Basics::BigInt:

Classes
union	long_double_parts

Static Public Member Functions
static uint64	accumulateNN (void *outBuf, const void *buf1, int nWords)
	Add number on to a temporary No null handling Returns carry.
static uint64	addNN (void *outBuf, const void *buf1, const void *buf2, int nWords)
	Add together 2 numbers w/ same number of digits No null handling Returns carry.
static void	castNumeric (uint64 *wordso, int nwdso, int32 typmodo, uint64 *wordsi, int nwdsi, int32 typmodi)
static bool	checkOverflowNN (const void *po, int nwdso, int32 typmodo)
static bool	checkOverflowNN (const void *po, int nwo, int nwdso, int32 typmodo)
static int	compareNN (const void *buf1, const void *buf2, int nWords)
	Compare integers, return -1, 0, 1.
static long double	convertPosToFloatNN (const void *bbuf, int bwords)
	Convert Numeric to a float helper function Input should not be negative / null.
static void	copy (void *buf, const void *src, int nWords)
	cpoy nWords from src to buf
static uint64	divUnsignedN1 (void *qbuf, int qw, int round, const void *ubuf, int uw, uint64 v)
static void	divUnsignedNN (void *qbuf, int qw, int round, uint64 *rbuf, int rw, const void *ubuf, int uw, const void *vbuf, int vw)
static void	fromIntNN (void *buf, int nWords, int64 val)
	Load from 64-bit signed int (does not handle NULL inside)
static void	incrementNN (void *buf, int nWords)
	Increment by 1.
static void	invertSign (void *buf, int nWords)
	Invert the sign of a number, performed in place, using the invert and +1 method, turns out NULLs are OK in this sense.
static bool	isEqualNN (const void *buf1, const void *buf2, int nWords)
	Check integers for equality. More...
static bool	isNeg (const void *buf, int nWords)
	Check if integer is less than zero.
static bool	isNull (const void *buf, int nWords)
	Check an integer for NULL.
static bool	isZero (const void *buf, int nWords)
	Check an integer for 0. More...
static void	mulUnsignedN1 (void *obuf, const void *ubuf, int uw, uint64 v)
	Multiply, unsigned only. uw words by 1 word -> uw+1 words Output array must be uw+1 words long; may not overlap inputs.
static void	mulUnsignedNN (void *obuf, const void *buf1, int nw1, const void *buf2, int nw2)
	Multiply, unsigned only. Output array must be nw1+nw2 long; may not overlap inputs PERF NOTE: Operates like a school boy, could do Karatsuba (or better)
static void	numericDivide (const uint64 *pa, int nwdsa, int32 typmoda, const uint64 *pb, int nwdsb, int32 typmodb, uint64 *outNum, int nwdso, int32 typmodo)
	Divide Numerics Handles negative / null input.
static void	numericMultiply (const uint64 *pa, int nwdsa, const uint64 *pb, int nwdsb, uint64 *outNum, int nwdso)
	Multiply Numerics , result in outNum Handles negative / null input.
static void	NumericRescaleDown (uint64 *wordso, int nwdso, int32 typmodo, uint64 *wordsi, int nwdsi, int32 typmodi)
static void	NumericRescaleSameScaleSmallerPrec (uint64 *wordso, int nwdso, int32 typmodo, uint64 *wordsi, int nwdsi, int32 typmodi)
static void	NumericRescaleUp (uint64 *wordso, int nwdso, int32 typmodo, uint64 *wordsi, int nwdsi, int32 typmodi)
static ifloat	numericToFloat (const void *buf, int nwds, ifloat tenthtoscale)
	Convert Numeric to a float Handles negative / null input. More...
static bool	rescaleNumeric (void *out, int ow, int pout, int sout, void *in, int iw, int pin, int sin)
	Rescale a given numeric to a specific prec/scale/nwds The input should have minimal precision to avoid unnecessary overflow; for example, "0" should have precision 0 (as generated by charToNumeric). Accepts signed numerics. Will set its "in" argument to abs(in).
static bool	setFromFloat (void *bbuf, int bwords, int typmod, long double value, bool round)
	Convert floating point multiplied by 10^scale to an integer This truncates if round is false; otherwise the numeric result is rounded. More...
static void	setNull (void *buf, int nWords)
	Set an integer to NULL.
static void	setNumericBoundsFromType (uint64 *numUpperBound, uint64 *numLowerBound, int nwdso, int32 typmod)
static void	setZero (void *buf, int nWords)
	Set an integer to 0.
static void	shiftLeftNN (void *buf, unsigned nw, unsigned bitsToShift)
	Shift a BigInt to the left (<<) by the given number of bits. The given BigInt must be positive and non-null.
static void	shiftRightNN (void *buf, unsigned nw, unsigned bitsToShift)
	Shift a BigInt to the right (>>) by the given number of bits. The given BigInt must be positive and non-null.
static void	subNN (void *outBuf, const void *buf1, const void *buf2, int nWords)
	Subtract 2 numbers w/ same number of digits No null handling.
static bool	toIntNN (int64 &out, const void *buf, int nWords)
	Convert to int (return false if there was an overflow)
static int	ucompareNN (const void *buf1, const void *buf2, int nWords)
static int	usedWordsUnsigned (const void *buf, int nWords)
	Calculate number of words that are actually used to represent the value (amount left after stripping leading 0's)

Detailed Description

Holds integer utilities A few are inlined for performance reasons. Most are in vertica.cpp.

Member Function Documentation

static bool Basics::BigInt::isEqualNN ( const void *  buf1, const void *  buf2, int  nWords  )

static

Check integers for equality.

Note

Optimized for small nWords; scan from end and break out of loop

Referenced by Vertica::VNumeric::equal().

static bool Basics::BigInt::isZero ( const void *  buf, int  nWords  )

static

Check an integer for 0.

Note

Optimized for small nWords; scan from end and break out of loop

Referenced by Vertica::VNumeric::isZero().

static ifloat Basics::BigInt::numericToFloat ( const void *  buf, int  nwds, ifloat  tenthtoscale  )

static

Convert Numeric to a float Handles negative / null input.

Parameters

tenthtoscale

10^-scale of the Numeric

Referenced by Vertica::VNumeric::toFloat().

bool Basics::BigInt::setFromFloat ( void *  bbuf, int  bwords, int  typmod, long double  value, bool  round  )

static

Convert floating point multiplied by 10^scale to an integer This truncates if round is false; otherwise the numeric result is rounded.

Returns

false if high bits were lost, true if reasonable fidelity was achieved

Referenced by Vertica::VNumeric::copy().

static int Basics::BigInt::ucompareNN ( const void *  buf1, const void *  buf2, int  nWords  )

inlinestatic

Compare integers, return -1, 0, 1

Referenced by Vertica::VNumeric::compareUnsigned().