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/*****************************************************************
*
* The Compcert verified compiler
*
* Xavier Leroy, INRIA Paris
*
* Copyright (c) 2016 Institut National de Recherche en Informatique et
* en Automatique.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the <organization> nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT
* HOLDER> BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
**********************************************************************/
/* Helper functions for 64-bit integer arithmetic. Reference C implementation */
#include "i64.h"
typedef unsigned long long u64;
typedef unsigned int u32;
/* Unsigned multiply high */
/* Hacker's Delight, algorithm 8.1, specialized to two 32-bit words */
u64 i64_umulh(u64 u, u64 v)
{
u32 u0 = u, u1 = u >> 32;
u32 v0 = v, v1 = v >> 32;
u32 w1, w2, w3, k;
u64 t;
t = (u64) u0 * (u64) v0;
k = t >> 32;
t = (u64) u1 * (u64) v0 + k;
w1 = t;
w2 = t >> 32;
t = (u64) u0 * (u64) v1 + w1;
k = t >> 32;
t = (u64) u1 * (u64) v1 + w2 + k;
return t;
}
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