cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

dual_stores.c (1595B)

      1/*
      2 *  Copyright(c) 2019-2021 Qualcomm Innovation Center, Inc. All Rights Reserved.
      3 *
      4 *  This program is free software; you can redistribute it and/or modify
      5 *  it under the terms of the GNU General Public License as published by
      6 *  the Free Software Foundation; either version 2 of the License, or
      7 *  (at your option) any later version.
      8 *
      9 *  This program is distributed in the hope that it will be useful,
     10 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
     11 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     12 *  GNU General Public License for more details.
     13 *
     14 *  You should have received a copy of the GNU General Public License
     15 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
     16 */
     17
     18#include <stdio.h>
     19
     20/*
     21 *  Make sure that two stores in the same packet honor proper
     22 *  semantics: slot 1 executes first, then slot 0.
     23 *  This is important when the addresses overlap.
     24 */
     25static inline void dual_stores(int *p, char *q, int x, char y)
     26{
     27  asm volatile("{\n\t"
     28               "    memw(%0) = %2\n\t"
     29               "    memb(%1) = %3\n\t"
     30               "}\n"
     31               :: "r"(p), "r"(q), "r"(x), "r"(y)
     32               : "memory");
     33}
     34
     35typedef union {
     36    int word;
     37    char byte;
     38} Dual;
     39
     40int err;
     41
     42static void check(Dual d, int expect)
     43{
     44    if (d.word != expect) {
     45        printf("ERROR: 0x%08x != 0x%08x\n", d.word, expect);
     46        err++;
     47    }
     48}
     49
     50int main()
     51{
     52    Dual d;
     53
     54    d.word = ~0;
     55    dual_stores(&d.word, &d.byte, 0x12345678, 0xff);
     56    check(d, 0x123456ff);
     57
     58    puts(err ? "FAIL" : "PASS");
     59    return err;
     60}