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/*
* Copyright (c) 2019 Advanced Micro Devices, Inc.
* All rights reserved.
*
* For use for simulation and test purposes only
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. Neither the name of the copyright holder 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 THE COPYRIGHT HOLDER OR CONTRIBUTORS 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.
*
* Authors: Brandon Potter
*/
#include <sys/mman.h>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <ctime>
int main(void)
{
uint64_t page_size = 0x1000;
uint64_t num_pages = 0x10000;
uint64_t length = page_size * num_pages;
void *raw = mmap(NULL, length, PROT_WRITE, MAP_ANON|MAP_PRIVATE, -1, 0);
uint8_t *mem = reinterpret_cast<uint8_t*>(raw);
srand(0xABCD);
uint64_t last_byte = page_size - 1;
uint64_t page_boundaries = num_pages - 1;
for (int i = 0; i < 2000; i++) {
uint64_t random_boundary = rand() % page_boundaries;
uint64_t boundary_offset = random_boundary * page_size;
uint64_t boundary_last_byte = boundary_offset + last_byte;
uint32_t *poke = reinterpret_cast<uint32_t*>(mem + boundary_last_byte);
printf("%p\n", poke);
uint32_t value = *poke;
}
return 0;
}
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