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email-tracker/external/duckdb/third_party/tpce-tool/include/utilities/BigMath.h
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/*
* Legal Notice
*
* This document and associated source code (the "Work") is a part of a
* benchmark specification maintained by the TPC.
*
* The TPC reserves all right, title, and interest to the Work as provided
* under U.S. and international laws, including without limitation all patent
* and trademark rights therein.
*
* No Warranty
*
* 1.1 TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, THE INFORMATION
* CONTAINED HEREIN IS PROVIDED "AS IS" AND WITH ALL FAULTS, AND THE
* AUTHORS AND DEVELOPERS OF THE WORK HEREBY DISCLAIM ALL OTHER
* WARRANTIES AND CONDITIONS, EITHER EXPRESS, IMPLIED OR STATUTORY,
* INCLUDING, BUT NOT LIMITED TO, ANY (IF ANY) IMPLIED WARRANTIES,
* DUTIES OR CONDITIONS OF MERCHANTABILITY, OF FITNESS FOR A PARTICULAR
* PURPOSE, OF ACCURACY OR COMPLETENESS OF RESPONSES, OF RESULTS, OF
* WORKMANLIKE EFFORT, OF LACK OF VIRUSES, AND OF LACK OF NEGLIGENCE.
* ALSO, THERE IS NO WARRANTY OR CONDITION OF TITLE, QUIET ENJOYMENT,
* QUIET POSSESSION, CORRESPONDENCE TO DESCRIPTION OR NON-INFRINGEMENT
* WITH REGARD TO THE WORK.
* 1.2 IN NO EVENT WILL ANY AUTHOR OR DEVELOPER OF THE WORK BE LIABLE TO
* ANY OTHER PARTY FOR ANY DAMAGES, INCLUDING BUT NOT LIMITED TO THE
* COST OF PROCURING SUBSTITUTE GOODS OR SERVICES, LOST PROFITS, LOSS
* OF USE, LOSS OF DATA, OR ANY INCIDENTAL, CONSEQUENTIAL, DIRECT,
* INDIRECT, OR SPECIAL DAMAGES WHETHER UNDER CONTRACT, TORT, WARRANTY,
* OR OTHERWISE, ARISING IN ANY WAY OUT OF THIS OR ANY OTHER AGREEMENT
* RELATING TO THE WORK, WHETHER OR NOT SUCH AUTHOR OR DEVELOPER HAD
* ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.
*
* Contributors
* - Cecil Reames, Matt Emmerton
*/
#ifndef BIGMATH_H
#define BIGMATH_H
#include "EGenStandardTypes.h"
namespace TPCE {
// For 128-bit integer multiplication
#define BIT63 UINT64_CONST(0x8000000000000000)
#define CARRY32 UINT64_CONST(0x100000000)
#define MASK32 UINT64_CONST(0xFFFFFFFF)
#define UPPER32 32
// Multiply 64-bit and 32-bit factors, followed by a right-shift of 64 bits
// (retaining upper 64-bit quantity) This is implemented as two 64-bit
// multiplications with summation of partial products.
inline UINT Mul6432WithShiftRight64(UINT64 seed, UINT range) {
UINT64 SL = (seed & MASK32), // lower 32 bits of seed
SU = (seed >> UPPER32), // upper 32 bits of seed
RL = range; // range
UINT64 p0 = (SL * RL), // partial products
p1 = (SU * RL), s;
s = p0;
s >>= UPPER32;
s += p1;
s >>= UPPER32;
return (UINT)s;
}
// Multiply two 64-bit factors, followed by a right-shift of 64 bits (retaining
// upper 64-bit quantity) This is implemented as four 64-bit multiplications
// with summation of partial products and carry.
inline UINT64 Mul6464WithShiftRight64(UINT64 seed, UINT64 range) {
UINT64 SL = (seed & MASK32), // lower 32 bits of seed
SU = (seed >> UPPER32), // upper 32 bits of seed
RL = (range & MASK32), // lower 32 bits of range
RU = (range >> UPPER32); // upper 32 bits of range
UINT64 p0 = (SL * RL), // partial products
p1 = (SU * RL), p2 = (SL * RU), p3 = (SU * RU), p12_carry = 0, s;
s = p0;
s >>= UPPER32;
s += p1;
p12_carry = ((((p1 & BIT63) || (s & BIT63)) && (p2 & BIT63)) ? CARRY32 : 0);
s += p2;
s >>= UPPER32;
s += p12_carry;
s += p3;
return s;
}
} // namespace TPCE
#endif // BIGMATH_H