bench/amd64cpuinfo.c


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/*
   BLAKE2 reference source code package - benchmark tool
  
   Copyright 2012, Samuel Neves <sneves@dei.uc.pt>.  You may use this under the
   terms of the CC0, the OpenSSL Licence, or the Apache Public License 2.0, at
   your option.  The terms of these licenses can be found at:
  
   - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0
   - OpenSSL license   : https://www.openssl.org/source/license.html
   - Apache 2.0        : http://www.apache.org/licenses/LICENSE-2.0
  
   More information about the BLAKE2 hash function can be found at
   https://blake2.net.
*/

unsigned long long cpucycles( void )
{
  unsigned long long result;
  asm volatile( ".byte 15;.byte 49;shlq $32,%%rdx;orq %%rdx,%%rax"
                : "=a" ( result ) ::  "%rdx" );
  return result;
}