LXR qemu/tests/tcg/hexagon/overflow.c

   1/*
   2 *  Copyright(c) 2021-2023 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 <stdlib.h>
  19#include <stdio.h>
  20#include <stdint.h>
  21#include <unistd.h>
  22#include <sys/types.h>
  23#include <fcntl.h>
  24#include <setjmp.h>
  25#include <signal.h>
  26
  27int err;
  28
  29#include "hex_test.h"
  30
  31static int32_t satub(int32_t src, int32_t *p, bool *ovf_result)
  32{
  33    int32_t result;
  34    uint32_t usr;
  35
  36    /*
  37     * This instruction can set bit 0 (OVF/overflow) in usr
  38     * Clear the bit first, then return that bit to the caller
  39     *
  40     * We also store the src into *p in the same packet, so we
  41     * can ensure the overflow doesn't get set when an exception
  42     * is generated.
  43     */
  44    asm volatile("r2 = usr\n\t"
  45                 "r2 = clrbit(r2, #0)\n\t"        /* clear overflow bit */
  46                 "usr = r2\n\t"
  47                 "{\n\t"
  48                 "    %0 = satub(%2)\n\t"
  49                 "    memw(%3) = %2\n\t"
  50                 "}\n\t"
  51                 "%1 = usr\n\t"
  52                 : "=r"(result), "=r"(usr)
  53                 : "r"(src), "r"(p)
  54                 : "r2", "usr", "memory");
  55  *ovf_result = (usr & 1);
  56  return result;
  57}
  58
  59bool read_usr_overflow(void)
  60{
  61    uint32_t usr;
  62    asm volatile("%0 = usr\n\t" : "=r"(usr));
  63    return usr & 1;
  64}
  65
  66bool get_usr_overflow(uint32_t usr)
  67{
  68    return usr & 1;
  69}
  70
  71bool get_usr_fp_invalid(uint32_t usr)
  72{
  73    return (usr >> 1) & 1;
  74}
  75
  76int32_t get_usr_lpcfg(uint32_t usr)
  77{
  78    return (usr >> 8) & 0x3;
  79}
  80
  81jmp_buf jmp_env;
  82bool usr_overflow;
  83
  84static void sig_segv(int sig, siginfo_t *info, void *puc)
  85{
  86    usr_overflow = read_usr_overflow();
  87    longjmp(jmp_env, 1);
  88}
  89
  90static void test_packet(void)
  91{
  92    int32_t convres;
  93    int32_t satres;
  94    uint32_t usr;
  95
  96    asm("r2 = usr\n\t"
  97        "r2 = clrbit(r2, #0)\n\t"        /* clear overflow bit */
  98        "r2 = clrbit(r2, #1)\n\t"        /* clear FP invalid bit */
  99        "usr = r2\n\t"
 100        "{\n\t"
 101        "    %0 = convert_sf2uw(%3):chop\n\t"
 102        "    %1 = satb(%4)\n\t"
 103        "}\n\t"
 104        "%2 = usr\n\t"
 105        : "=r"(convres), "=r"(satres), "=r"(usr)
 106        : "r"(0x6a051b86), "r"(0x0410eec0)
 107        : "r2", "usr");
 108
 109    check32(convres, 0xffffffff);
 110    check32(satres, 0x7f);
 111    check32(get_usr_overflow(usr), true);
 112    check32(get_usr_fp_invalid(usr), true);
 113
 114    asm("r2 = usr\n\t"
 115        "r2 = clrbit(r2, #0)\n\t"        /* clear overflow bit */
 116        "usr = r2\n\t"
 117        "%2 = r2\n\t"
 118        "p3 = sp3loop0(1f, #1)\n\t"
 119        "1:\n\t"
 120        "{\n\t"
 121        "    %0 = satb(%2)\n\t"
 122        "}:endloop0\n\t"
 123        "%1 = usr\n\t"
 124        : "=r"(satres), "=r"(usr)
 125        : "r"(0x0410eec0)
 126        : "r2", "usr", "p3", "sa0", "lc0");
 127
 128    check32(satres, 0x7f);
 129    check32(get_usr_overflow(usr), true);
 130    check32(get_usr_lpcfg(usr), 2);
 131}
 132
 133int main()
 134{
 135    struct sigaction act;
 136    bool ovf;
 137
 138    /* SIGSEGV test */
 139    act.sa_sigaction = sig_segv;
 140    sigemptyset(&act.sa_mask);
 141    act.sa_flags = SA_SIGINFO;
 142    sigaction(SIGSEGV, &act, NULL);
 143    if (setjmp(jmp_env) == 0) {
 144        satub(300, 0, &ovf);
 145    }
 146
 147    act.sa_handler = SIG_DFL;
 148    sigemptyset(&act.sa_mask);
 149    act.sa_flags = 0;
 150
 151    check32(usr_overflow, false);
 152
 153    test_packet();
 154
 155    puts(err ? "FAIL" : "PASS");
 156    return err ? EXIT_FAILURE : EXIT_SUCCESS;
 157}
 158